CN107205557A - Seat arrangement with head restraint assembly - Google Patents

Abstract

A seating arrangement comprising: a seat assembly; a backrest assembly operatively coupled to the seat assembly; and a headrest assembly coupled to the backrest assembly. The headrest assembly includes: a support device pivotably coupled to the backrest assembly for pivotal movement about a first pivot axis; a headrest member pivotally coupled to the support arrangement for pivotal movement about a second pivot axis spaced from the first pivot axis; and a slide coupling the headrest member to the support device to allow vertical sliding adjustment of the headrest member relative to the support device along an arcuate path.

Description

Seat arrangement with head restraint assembly

technical field

Various embodiments relate to a seating arrangement, and more particularly to an office chair assembly including a headrest assembly having a pair of separately pivotable pivot adjustment means and vertical adjustment means.

Contents of the invention

In one embodiment, the seating arrangement comprises: a seat assembly adapted to support a user; a backrest assembly operatively coupled to the seat assembly and adapted to support the user; and a headrest assembly, The head restraint assembly is coupled to the backrest assembly. The headrest assembly includes: a support device pivotally coupled to the backrest assembly for pivotal movement about a first pivot axis; a headrest member pivotally coupled to the support device for pivotal movement about the first pivot axis; the pivotal movement of the second pivot axis spaced apart from the first pivot axis; and a slide mechanism coupling the head restraint member to the support means to allow vertical sliding adjustment of the head restraint member along an arcuate path relative to the support means.

In another embodiment, a headrest assembly is adapted to be coupled to a seating arrangement, the headrest assembly comprising: support means configured to be pivotally coupled to a backrest assembly of the seating arrangement about a first pivot axis pivotal movement; a head restraint, which is pivotally coupled to the support means for pivotal movement around a second pivot axis spaced apart from the first pivot axis; and a sliding device, which causes the head restraint to Coupled to the support means, and the slide means is configured to permit vertical sliding adjustment of the head restraint member along an arcuate path relative to the support means.

In yet another embodiment, a seating arrangement comprises: a seat assembly adapted to support a user; a back assembly operatively coupled to the seat assembly and adapted to support a user; and a headrest assembly , the head restraint assembly is coupled to the backrest assembly. The headrest assembly includes: a support device coupled to the backrest assembly; a headrest member having an arcuate track portion; and a sliding device slidably coupling the track portion of the headrest member to the support means such that sliding adjustment of the head restraint relative to the support means causes the head restraint to travel along an arcuate path relative to the support means.

In yet another embodiment, a headrest assembly is adapted to be coupled to a seating arrangement, the headrest assembly comprising: a support device configured to be operatively coupled to a backrest assembly of the seating arrangement; a headrest member, the headrest The pillow has an arcuate support portion; and a sliding device that slidably couples the support portion of the head restraint to the support means such that sliding adjustment of the head restraint relative to the support causes the head restraint to follow an arcuate path relative to the The support device travels.

In another embodiment, a seating arrangement comprises: a seat assembly adapted to support a user; a back assembly operatively coupled to the seat assembly and adapted to support a user; and a headrest assembly , the head restraint assembly is coupled to the backrest assembly. The headrest assembly includes: a support device pivotably coupled to the backrest assembly for pivotal movement about a first pivot axis; a headrest member configured to support a user and pivotally coupled to the support means to pivotally move around a second pivot axis spaced apart from the first pivot axis, wherein the pivoting of the head restraint is allowed around the second pivot axis independently of the pivoting of the support means around the first pivot axis; and the coupling means, The coupling device operably couples the head restraint member to the support device such that the head restraint member can pivot about a pivot area spaced from the first pivot axis and the second pivot axis.

In yet another embodiment, a head restraint assembly is adapted to be coupled to a seating arrangement, the head restraint assembly comprising: support means configured to be pivotably coupled to a backrest assembly of the seating arrangement about a first pivot axis pivotal movement; a head restraint member pivotally coupled to the support device for pivotal movement about a second pivot axis spaced from the first pivot axis, wherein the head restraint member is allowed to move about the second pivot axis pivoting independently of the pivoting of the support device around the first pivot axis; and a coupling device configured to operatively couple the head restraint to the support device so that the head restraint can rotate about the first pivot axis and the second pivot axis. Pivot zones separated by pivot lines pivot.

In yet another embodiment, a seating arrangement comprises: a seat assembly adapted to support a user; a back assembly operably coupled to the seat assembly and adapted to support a user; and a headrest assembly, the head restraint assembly is coupled to the backrest assembly. The head restraint assembly includes: a support device pivotally coupled to the backrest assembly for pivotal movement about a first pivot axis, wherein the support device is located substantially forward of the backrest assembly when the head restraint assembly is in the first position, and When the headrest assembly is in the second position, it is located substantially behind the backrest assembly; a headrest member comprising a support surface adapted to support the user and pivotally coupled to the support means to about the first pivot axis The second spaced pivot axis pivots, wherein the support surface faces substantially forward when the head restraint assembly is in the first position and faces substantially rearward when the head restraint assembly is in the second position, and wherein the head restraint member faces substantially rearward when the head restraint assembly is in the first position comprising an upper edge and a lower edge; and a sliding device that couples the head restraint to the support to allow the head restraint to be adjusted vertically relative to the support, and wherein the head restraint is positioned when the head restraint assembly is in the first position The upper edge of the member is close to the supporting device, and when the headrest assembly is in the second position, the lower edge of the headrest member is close to the supporting device.

Another embodiment comprises a seating arrangement comprising: a seat assembly adapted to support a user; a back assembly operatively coupled to the seat assembly and adapted to support a user; and a head Pillow components. the head restraint assembly comprises: a head restraint member adapted to support a user; a support device operably coupling the head restraint assembly to the backrest assembly such that the head restraint member can be adjusted vertically relative to the backrest assembly, wherein at least one of the head restraint member and the support means comprises a first plurality of detents and a second plurality of detents, wherein detents of the first plurality of detents offset detents of the second plurality of detents and an engagement member that alternately engages the first plurality of detents and the second plurality of detents when the head restraint is adjusted vertically.

Yet another embodiment includes a headrest assembly device adapted to be coupled to a seating arrangement, the headrest assembly device comprising: a headrest member adapted to support a user; a support device, the support device The head restraint is configured to be operatively coupled to a backrest assembly of the seating arrangement such that the head restraint is vertically adjustable relative to the backrest, wherein at least one of the head restraint and the support means comprises a first plurality of detents and a second plurality of detents. a plurality of locking pins, wherein the locking pins of the first plurality of locking pins offset the locking pins of the second plurality of locking pins; A plurality of detents engages with a second plurality of detents.

Yet another embodiment comprises a seating arrangement comprising: a seat support structure comprising a seat support surface configured to support a user seated thereon; a back support structure comprising: upward an extension, the upwardly extending portion adapted to move between an upright position and a reclined position, a control linkage coupled to the rear of the seat support structure, and a second end coupled to the rear portion of the back support structure; the back support surface, which generally faces forward and is configured to support the back of a seated user, and has a lower portion and an upper portion coupled to an upwardly extending portion of the back support; and a back link, which A back link is coupled to a lower portion of the back support surface and to the seat support structure, wherein the back link brings the back support surface forward relative to the upwardly extending portion of the back support structure when the back support structure moves from the upright position to the reclined position move. The seating arrangement also includes a headrest assembly coupled to the back support structure, the headrest assembly comprising: a support device pivotally coupled to the backrest assembly for pivotal movement about a first pivot axis; the headrest a member, the head restraint is pivotally coupled to the support device for pivotal movement around a second pivot axis spaced apart from the first pivot axis; and a sliding device that couples the head restraint to the support device so that Allows vertical sliding adjustment of the head restraint relative to the back support structure.

The features and advantages of these and other various embodiments will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and drawings.

Description of drawings

Figure 1 is a front perspective view of an embodiment of a chair assembly;

Figure 2 is a rear perspective view of the chair assembly;

Figure 3 is a side view of the chair assembly showing the chair assembly in a lowered position, and in phantom in a raised position, and showing the seat assembly in a retracted position and in phantom in an extended position;

Figure 4 is a side view of the chair assembly showing the chair assembly in an upright position with a reclined position shown in phantom;

Figure 5A is an exploded view of the seat assembly;

Figure 5B is an enlarged perspective view of the chair assembly with a portion of the seat assembly removed to show the spring support assembly;

Figure 6 is an exploded perspective view of the seat assembly;

Figure 7 is a top perspective view of the seat assembly;

Figure 8 is a bottom perspective view of the seat assembly;

Figure 9 is an exploded bottom perspective view of the cover assembly and seat assembly;

Figure 10 is a cross-sectional view of the sleeve assembly;

Figure 11 is an exploded perspective view of an alternate embodiment of a seat assembly;

Figure 11A is an exploded perspective view of another alternative embodiment of a seat assembly;

Figure 12 is a top perspective view of an alternate embodiment of a seat assembly;

Figure 13 is a bottom perspective view of an alternate embodiment of a seat assembly;

Figure 14 is an exploded bottom perspective view of an alternate embodiment of a seat assembly;

Figure 15 is a top perspective view of a second alternative embodiment of a seat assembly;

16 is a cross-sectional view of a second alternative embodiment of the seat assembly along line XVI-XVI of FIG. 15;

Figure 17 is a cross-sectional view of a second alternative embodiment of the seat assembly along line XVII-XVII of Figure 15;

Figure 18 is a front perspective view of the backrest assembly;

Figure 19 is a side view of the backrest assembly;

Figure 20A is an exploded front perspective view of the backrest assembly;

Figure 20B is an exploded rear perspective view of the backrest assembly;

Figure 21 is an enlarged perspective view of area XXI of Figure 20A;

Figure 22 is an enlarged perspective view of area XXII of Figure 2;

Figure 23 is a cross-sectional view of the upper backrest pivot assembly along line XXIII-XXIII of Figure 18;

Figure 24A is an exploded rear perspective view of the upper back pivot assembly;

Figure 24B is an exploded front perspective view of the upper back pivot assembly;

Figure 25 is an enlarged perspective view of area XXV of Figure 20B;

Figure 26A is an enlarged perspective view of a comfort component and a lumbar support assembly;

Figure 26B is a rear perspective view of the comfort component and lumbar support assembly;

Figure 27A is a front perspective view of a pawl assembly;

Figure 27B is a rear perspective view of the pawl assembly;

Figure 28 is a partial cross-sectional perspective view along line XXVIII-XXVIII of Figure 26B;

Figure 29A is a perspective view of the backrest assembly with a portion of the comfort component cut away;

Figure 29B is an enlarged perspective view of a portion of the backrest assembly;

Figure 30 is a perspective view of an alternate embodiment of a lumbar support assembly;

Figure 31 is a cross-sectional view of a backrest assembly and an exterior trim assembly;

32A-32D are step-by-step assembly views of the backrest assembly and exterior trim assembly;

Figure 33 is an enlarged perspective view of area XXXIII of Figure 32A;

34A-34H are a series of rear elevational views of the sequential steps of a bollard and a guyline secured thereto;

Figures 35G and 35H are alternate sequential steps for securing the guy line to the bollard;

Figure 36 is an exploded view of an alternate embodiment of a backrest assembly;

37 is a cross-sectional side view of a top portion of an alternate embodiment of a backrest assembly;

38 is a cross-sectional side view of a side portion of an alternate embodiment of a backrest assembly;

Figure 39 is a front elevational view of the retaining component;

Figure 40 is a front elevational view of the retaining member in a turned inside out orientation;

Figure 41 is a partial front elevational view of a retaining member sewn to a cover member;

Figure 42 is a perspective view of the control input assembly with the seat support plate supported thereon;

Figure 43 is a perspective view of the control input assembly with certain elements removed to reveal its interior;

Figure 44 is an exploded view of the control input assembly;

Figure 45 is a side view of the control input assembly;

Figure 46A is a front perspective view of a back support structure;

Figure 46B is an exploded perspective view of the back support structure;

Figure 47 is a side view of the chair assembly showing its various pivot points;

Fig. 48 is a side perspective view of the control assembly showing a plurality of pivot points associated therewith;

Figure 49 is a cross-sectional view of a chair showing the backrest in an upright position with the lumbar adjustment set at a neutral setting;

Figure 50 is a cross-sectional view of a chair showing the backrest in an upright position with the lumbar portion set to a straight configuration;

Figure 51 is a cross-sectional view of a chair showing the back recline with the lumbar adjusted to a neutral position;

Figure 52 is a cross-sectional view of the chair in the reclined position with the lumbar adjusted to a straight configuration;

Figure 52A is a cross-sectional view of a chair showing the back recline with the lumbar portion of the shell set to maximum curvature;

Figure 53 is an exploded view of a moment arm displacement assembly;

Figure 54 is a cross-sectional perspective view of the moment arm displacement assembly along line LIV-LIV of Figure 43;

Figure 55 is a top plan view of a plurality of control linkages;

Figure 56 is an exploded view of a control linkage assembly;

Figure 57A is a side perspective view of the control assembly with the moment arm displacement member in the low tension position and the chair assembly in the upright position;

Figure 57B is a side perspective view of the control assembly with the moment arm displacement member in the low tension position and the chair assembly in the reclined position;

Figure 58A is a side perspective view of the control assembly with the moment arm displacement in the high tension position and the chair assembly in the upright position;

Figure 58B is a side perspective view of the control assembly with the moment arm displacement in the high tension position and the chair assembly in the reclined position;

Figure 59 is a graph of torque versus caster at low and high tension settings;

Figure 60 is a perspective view of a direct drive assembly with the seat support plate exploded therefrom;

Figure 61 is an exploded perspective view of a direct drive assembly;

Figure 62 is a perspective view of a vertical height control assembly;

Figure 63 is a perspective view of a vertical height control assembly;

Figure 64 is a side view of the vertical height control assembly;

65 is a cross-sectional perspective view of the first input control assembly along line LXV-LXV of FIG. 42;

Figure 66A is an exploded perspective view of a control input assembly;

Figure 66B is an enlarged perspective view of the clutch member of the first control input assembly;

Figure 66C is an exploded perspective view of the control input assembly;

Figure 67 is a cross-sectional side view of the variable backrest control assembly along line LXVII-LXVII of Figure 42;

Figure 68 is a perspective view of an alternate embodiment of a chair assembly including a headrest assembly;

Figure 69 is a rear perspective view of the head restraint assembly;

Figure 70A is an exploded rear perspective view of the head restraint assembly;

Figure 70B is an exploded rear perspective view of an alternate embodiment of a head restraint assembly;

Figure 71 is an exploded view of components of an alternate embodiment of a backrest shell;

Figure 72 is a cross-sectional view of the headrest assembly along line LXXII-LXXII of Figure 69;

Figure 73 is a rear perspective view of the fabric member combined with the subframe member of the head restraint assembly;

Figure 74 is a cross-sectional view of the head restraint assembly;

Figure 75 is an enlarged view of the head restraint assembly;

Figure 76 is a rear perspective view of the head restraint assembly with the cover removed;

Figure 77 is a rear perspective view of the head restraint assembly with the cover and guide removed;

78A-78K are side views of the head restraint assembly in various configurations and orientations;

Figure 79 is a perspective view of another embodiment of a chair assembly;

Figure 80 is a front elevational view of an embodiment of the chair assembly of Figure 79;

Figure 81 is a first side view of an embodiment of the chair assembly of Figure 79;

Figure 82 is a second side view of an embodiment of the chair assembly of Figure 79;

Figure 83 is a rear side view of an embodiment of the chair assembly of Figure 79;

Figure 84 is a top plan view of an embodiment of the chair assembly of Figure 79;

Figure 85 is a bottom plan view of an embodiment of the chair assembly of Figure 79;

Figure 86 is a perspective view of another embodiment of a chair assembly;

Figure 87 is a front elevational view of an embodiment of the chair assembly of Figure 86;

Figure 88 is a first side view of an embodiment of the chair assembly of Figure 86;

Figure 89 is a second side view of an embodiment of the chair assembly of Figure 86;

Figure 90 is a rear side view of an embodiment of the chair assembly of Figure 86;

Figure 91 is a top plan view of an embodiment of the chair assembly of Figure 86; and

92 is a bottom plan view of an embodiment of the chair assembly of FIG. 86. FIG.

detailed description

For the purposes described herein, the terms "upper", "lower", "right", "left", "rear", "front", "vertical", "horizontal" and their derivatives shall refer to Oriented example. However, it should be understood that the various embodiments may assume various alternative orientations and step sequences unless expressly stated to the contrary. It is also to be understood that the particular apparatus and processes shown in the drawings, and described in the following specification, are exemplary embodiments of the inventive concepts defined by the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless expressly stated as such in the claims. Various elements of the embodiments disclosed herein may be described as being operably coupled to each other, including elements coupled directly or indirectly to each other. Furthermore, the term "chair" as used herein encompasses various seating arrangements such as office chairs, car seats, home seats, stadium seats, theater seats, and the like.

Reference numeral 10 (FIGS. 1 and 2) generally designates an embodiment of a chair assembly. In the illustrated example, the chair assembly 10 includes a caster base assembly 12 abutting a supported floor surface 13, a control or support assembly 14 supported by the caster base assembly 12, each operatively connected to the control assembly. 14 coupled seat assembly 16 and back assembly 18 , and a pair of arm assemblies 20 . The control assembly 14 (FIG. 3) is operably coupled to the base assembly 12 such that the seat assembly 16, the back assembly 18 and the arm assembly 20 can be moved vertically between a fully lowered position A and a fully raised position B. adjusted and pivoted in direction 22 about a vertical axis 21 . Seat assembly 16 is operatively coupled to control assembly 14 such that seat assembly 16 is longitudinally adjustable between a fully retracted position C and a fully deployed position D relative to control assembly 14 . The seat assembly 16 (FIG. 4) and the back assembly 18 are operably coupled to the control assembly 14 and to each other such that the back assembly 18 is movable between a fully upright position E and a fully reclined position F, and Further, the seat assembly 16 is movable between a fully upright position G and a fully reclined position H, which respectively correspond to the fully upright position E and the fully reclined position F of the backrest assembly 18 .

Base assembly 12 includes a plurality of pedestal arms 24 that extend radially and are spaced from each other about a hollow central post 26 that receives a pneumatic cylinder 28 therein. Each pedestal arm 24 is supported above the floor surface 13 by an associated caster assembly 30 . Although the base assembly 12 is shown as comprising a multi-armed pedestal assembly, it is noted that other suitable support structures may be used, including but not limited to fixed posts, multi-leg arrangements, vehicle seat support assemblies, stadium seating arrangements , home seating arrangements, theater seating arrangements, and so on.

The seat assembly 16 ( FIG. 5A ) includes a relatively rigid seat support panel 32 having a front edge 34 , a rear edge 36 , and a pair of C-shaped rails 38 that define the side edges of the seat support panel 32 ( FIG. 5B), and extends between the leading edge 34 and the trailing edge 36. Seat assembly 16 also includes a flexible, resilient seat shell 40 having a pair of upturned side portions 42 and an upturned rear portion 44 that cooperate to form an upwardly disposed generally concave shape, and a leading edge 45. In the illustrated example, the seat shell 40 is constructed of a relatively pliable material such as thermoplastic elastomer (TPE). In assembly, the seat outer shell 40 is secured and sandwiched between the seat support plate 32 and a plastic, flexible, resilient seat pan 46 secured to the seat support plate 32 by a plurality of mechanical fasteners. The seat pan 46 includes a front edge 48, a rear edge 50, side edges 52 extending between the front edge 48 and the rear edge 50, and top and bottom surfaces 54, 56 mating into an upwardly disposed generally concave shape. In the illustrated example, the seat pan 46 includes a plurality of longitudinally extending slots 58 extending forwardly from the rear edge 50 . The slots 58 interfit therebetween to define a plurality of fingers 60, each finger 60 being individually pliable and resilient. The seat pan 46 also includes a plurality of transversely oriented elongated apertures 62 located adjacent the front edge 48 . The apertures 62 cooperate to increase the overall bendability of the seat pan 46 in their area, and specifically allow a forward portion 64 of the seat pan 46 to flex in a vertical direction 66 relative to a rearward portion 68 of the seat pan 46, as discussed further below. of. Seat assembly 16 also includes a foam upholstery member 70 that has an upper surface 76 and that rests on top surface 54 of seat pan 46 and is sunken within seat outer shell 40 . The seat assembly 16 also includes a fabric seat cover 72 having a front edge 73 , a rear edge 75 , and a pair of side edges 77 extending between the pair of front and rear edges 73 , 75 . A spring support assembly 78 ( FIGS. 5A and 5B ) is secured to the seat assembly 16 and is adapted to flexibly support the front portion 64 of the seat pan 46 to bend in the vertical direction 66 . In the illustrated example, the spring support assembly 78 includes a support housing 80 comprising foam and having side portions 82 defining an upwardly concave arcuate shape. The spring support assembly 78 also includes a relatively rigid attachment member 84 extending laterally between the side portions 82 of the support housing 80 and positioned between the support housing 80 and the front portion 64 of the seat pan 46 . A plurality of mechanical fasteners 86 secure the support housing 80 and the attachment member 84 to the front portion 64 of the seat pan 46 . The spring support assembly 78 also includes a pair of cantilever springs 88 each having a distal end 90 received through a corresponding aperture 92 of the attachment member 84, and a proximal end 94 secured to the seat support plate 32 such that each cantilever spring Distal end 90 of 88 may bend in vertical direction 66 . A pair of linear bearings 96 are fixedly attached to attachment member 84 and aligned with apertures 92 thereof such that each linear bearing 96 slidably receives a distal end 90 of a corresponding cantilever spring 88 . In operation, the cantilever springs 88 cooperate to allow the front portion 64 of the seat pan 46, and more generally, to The entire front portion of the seat assembly 16 is curved in a vertical direction 66 .

Reference numeral 16a (FIG. 6) generally designates another embodiment of a seat assembly. Seat assembly 16a is similar to previously described seat assembly 16, so like parts appearing respectively in FIGS. have the suffix "a". The seat assembly 16a includes a relatively rigid seat support panel 32a having a front edge 34a, a rear edge 36a, and a pair of C-shaped rails 38a that define the side edges of the seat support panel 32a and connect the front edge 34a and the rear edge 36a extends between. Seat assembly 16a also includes a flexible resilient seat shell 40a (FIGS. 6 and 7) having a pair of upturned side portions 42a each terminated at a side edge 43a, and a front edge 45a, and an upward Turned rear portion 44a, which terminates in a rear edge 47a and includes a petal portion 49a, wherein side portions 42a and rear portion 44a cooperate to form a three-dimensionally upwardly disposed generally concave shape. Seat shell 40a is constructed of a relatively pliable material, such as thermoplastic elastomer (TPE), and is molded as a single, unitary piece. In assembly as described in further detail below, the seat outer shell 40a is secured and sandwiched between the seat support plate 32a and a plastic, flexible, resilient seat pan 46a, which is secured to the seat by a plurality of mechanical fasteners. Support plate 32a. Seat pan 46a includes a front edge 48a, rear edge 50a, side edges 52a extending between front edge 48a and rear edge 50a, top surface 54a and bottom surface 56a mating into an upwardly disposed generally concave shape. In the illustrated example, the seat pan 46a includes a plurality of longitudinally extending slots 58a that extend forwardly from the rear edge 50a. The slots 58a cooperate therebetween to define a plurality of fingers 60a, each finger 60a being individually pliable and resilient. The seat pan 46a also includes a plurality of transversely oriented elongated apertures 62a located adjacent the front edge 48a. The apertures 62a cooperate to increase the overall bendability of the seat pan 46a in their area, and specifically allow a forward portion 64a of the seat pan 46a to flex in a vertical direction 66a relative to a rearward portion 68a of the seat pan 46a, as discussed further below. of. The seat assembly 16a also includes a foam upholstery member 70a that has an upper surface 76a and that rests on the top surface 54a of the seat pan 46a and is sunken within the seat outer shell 40a. The seat assembly 16a also includes a fabric seat cover 72a having a front edge 73a, a rear edge 75a, and a pair of side edges 77a extending therebetween. Seat assembly 16a is supported by spring support assembly 78a (FIG. 6), which is similar in structure and operation to spring support assembly 78 previously described.

As best seen in Figures 7 and 8, the flexible, resilient seat shell 40a and fabric seat cover 72a cooperate to form an exterior trim cover assembly or cover 100a. Specifically, the side edge 43a of the seat shell 40a and the side edge 77a of the seat cover 72a, the front edge 45a of the seat shell 40a and the front edge 73a of the seat cover 72a, and the rear edge 47a of the seat shell 40a and the seat cover 72a The rear edges 75a of the sleeves are respectively attached to each other to form the sleeve 100a and define the interior space 102a therein.

The petal portion 49a of the seat shell 40a includes a pair of corner edges 104a that extend each along a corner 106a of the seat shell 40a between the rear portion 44a and the corresponding side portion 42a so that the petal portion 49a can be positioned at Move between open position I and closed position J. In the illustrated example, each corner edge 104a of the petal portion 49a includes a plurality of tabs 108a spaced from each other along the corner edge 104a, each tab including an aperture 110a extending therethrough. The tab 108a of the corner edge 104a is spaced apart from a plurality of tabs 112a spaced from one another along the corner edge 114a of each side portion 42a. Each tab 112a includes an aperture 116a extending therethrough. The seat shell 40a also includes a plurality of integrally molded coupling tabs 118a spaced from one another about the inner edge 121a of the seat shell 40a, each having a Z-shaped, cross-sectional configuration.

In assembly, the exterior trim cover assembly 100a (FIG. 9) is constructed as described above from the seat shell 40a and seat cover 72a. The seat pan 46a, upholstery component 70a and spring support assembly 78a are then arranged relative to each other and assembled with the exterior trim cover assembly 100a by placing the flap 49a in the open position I, placing the seat pan 46a, upholstery component 70a and The spring support assembly 78a is positioned within the interior space 102a and then moves the flap 49a to the closed position J. A pair of quick connect fasteners 120a each includes a plurality of snap couplings 122a spaced from one another along the length of an L-shaped body portion 124a. When assembled, the snap couplings 122a are extended through the apertures 110a, 116a of the tabs 108a, 112a and are snap-received within corresponding apertures 126a of the seat pan 46a, thereby securing the corner edges 104a, 114a to the seat The disc 46a fixes the flap portion 49a in the closed position J.

Later in assembly, the coupling tabs 118a (FIG. 10) are positioned in corresponding apertures 130a of the seat pan 46a so that the set assembly 100a is temporarily secured to the seat pan 46a, thereby allowing further manipulation of the set during assembly. Seat assembly 16a, while retaining cover assembly 100a connected and aligned with seat pan 46a. As used herein, "temporarily securing" is defined as a securing that is not intended to be used alone to keep the cover assembly 100a secured to the seat pan 46a during normal use of the chair assembly throughout the normal usable life of the chair assembly. . The support plate 32a is then secured to the underside of the seat pan 46a by a plurality of screws 132a thereby sandwiching the coupling tab 118a between the support plate 32a and the seat pan 46a and permanently securing the cover assembly 100a to the seat pan 46a . As used herein, "permanently secured" is defined as a fixation that is expected to keep the cover assembly secured to the seat pan 46a during normal use of the chair assembly throughout the normal useful life of the chair assembly.

Reference numeral 16b (FIG. 11) generally designates another embodiment of a seat assembly. Seat assembly 16b is similar to previously described seat assembly 16 and/or seat assembly 16a, so like parts appearing in FIGS. 5A-10 and FIGS. The suffix "b" in the designation of the latter. In the illustrated example, seat assembly 16b is similar in configuration and construction to seat assembly 16 and seat assembly 16a, with the most notable exception being an alternatively configured and constructed seat outer shell 40b and exterior trim cover 100b.

Seat assembly 16b (FIG. 11) includes a flexible, resilient seat shell 40b having a pair of upturned side portions 42b each terminating at a side edge 43b, a front edge 45b, and a rear edge 47b The upwardly turned rear portion 44b, wherein the side portions 42b and the rear portion 44b cooperate to form a three-dimensionally upwardly disposed generally concave shape. Seat shell 40b is constructed of a relatively pliable material, such as thermoplastic elastomer (TPE), and is molded as a single, unitary piece. In assembly as described in further detail below, the seat outer shell 40b is fixed and sandwiched between the seat support plate 32b, a plastic, flexible, resilient seat pan 46b, and a plastic, substantially rigid outer covering 51b, which Each is secured to the seat support plate 32b by a plurality of mechanical fasteners. The outer covering 51b has an upwardly arcuate shape, and includes a rear wall 53b and a pair of forwardly extending side walls 55b, each of which includes a leading edge 57b, and wherein the rear wall 53b and the side walls 55b cooperate to form an uppermost Edge 59b. Seat pan 46b includes a front edge 48b, rear edge 50b, side edges 52b extending between front edge 48b and rear edge 50b, top surface 54b and bottom surface 56b mating into an upwardly disposed generally concave shape.

As best seen in Figures 12 and 13, the pliable resilient seat shell 40b, fabric seat cover 72b and outer cover 51b cooperate to form an exterior trim cover assembly or cover 100b. In the illustrated example, the side edge 43b of the seat shell 40b and the side edge 77b of the seat cover 72b, the front edge 45b of the seat shell 40b and the front edge 73b of the seat cover 72b, and the rear edge 47b of the seat shell 40b The rear edges 75b of the seat cover 72b and the seat cover 72b are respectively attached to each other such that the seat shell 40b and the fabric seat cover 72b cooperate with the outer cover 51b to form the cover 100b and define the interior space 102b therein. The seat shell 40b also includes a plurality of integrally molded coupling tabs 118b spaced from one another about the inner edge 121b of the seat shell 40b, each having a Z-shaped, cross-sectional configuration.

In assembly, the seat shell 40b and seat cover 72b of the exterior trim cover assembly 100b (FIG. 9) are coupled to each other as described above. As best shown in Figures 15 and 16, side portions 42b of seat shell 40b are coupled to fabric seat cover 72b to define a corner 79b therebetween. Note here that using both the fabric material of the fabric seat cover 72b and the TPE of the seat shell 40b provides a sharp, aesthetically pleasing angular angle β of 90° or less, while providing a soft, elastic, deformable touch to the user By. The seat pan 46b, upholstery member 70b and spring support assembly 78b are then arranged relative to each other and positioned within the interior space 102b of the cover 100b. Subsequently, the shell 40b is secured to the seat pan 46b in lateral direction displacement by a plurality of integral hook couplings 123b spaced from each other around the perimeter of the shell 40b and engaged around the sides and sides of the seat pan 46b. The rear peripherally extends downwardly extending trim portion 125b. The shell 40b (FIG. 17) also includes a plurality of Z-shaped couplings 127b integral with the shell 40b, which are received within corresponding apertures 129b of the seat pan 46b, thereby temporarily securing the shell 40b to the seat with respect to vertical displacement. Disc 46b.

Thereafter in assembly, the outer cover 51b (FIG. 17) includes a plurality of integrally formed L-shaped hooks 131b which are spaced apart from each other along the side walls 55b and slidably engage corresponding plurality of hooks 131b integrally formed with the seat pan 46b. Angled couplings 133b are formed. Specifically, when the cover 51b is slid forward relative to the seat pan 46b, the hook 131b engages the coupler 133b. Cover 51b is then held in place by a pair of screws 135b which extend through corresponding apertures 137b of cover 51b and are received in threads in corresponding sleeves 139b of seat pan 46b, thereby trapping coupling 127b. in the pores 129b. The support plate 32b is then secured to the underside of the seat pan 46b by a plurality of screws 132b such that a plurality of spaced-apart coupling tabs 141b integral with the outer cover 51b are sandwiched between the support plate 32b and the seat pan 46b, and Cover assembly 100b is permanently secured to seat pan 46b. Note here that the terms "temporarily fixed" and "permanently fixed" are defined above.

The back assembly 18 (FIGS. 18-20B) includes a back frame assembly 200 and a back support assembly 202 supported thereby. The back frame assembly 200 generally comprises a substantially rigid material, such as metal, and includes a transversely extending top frame portion 204, a transversely extending bottom frame portion 206, and a pair of curved side frame portions 208, which Extending between and cooperating with top frame portion 204 and bottom frame portion 206 to define an opening 210 having a relatively large upper dimension 212 and a relatively narrow lower dimension 214 .

The back assembly 18 also includes a pliable resilient plastic back shell 216 having an upper portion 218, a lower portion 220, a pair of side edges 222 extending between the upper portion 218 and the lower portion 220, a forward surface 224 and A rearwardly facing surface 226 wherein upper portion 218 is generally wider than lower portion 220 , and lower portion 220 tapers downwardly to generally follow the configuration of the rear elevation of frame assembly 200 . A lower reinforcement member 228 ( FIG. 29A ) is attached to hooks 230 of the lower portion 220 of the back shell 216 . The reinforcement member 228 includes a plurality of protrusions 232 that engage a plurality of reinforcement ribs 250 of the back shell 216 to prevent side-to-side movement of the lower reinforcement member 228 relative to the back shell 216 while the reinforcement member 228 pivots. A point or axis 590 pivotally interconnects the back control linkage 236 and the lower portion 220 of the back housing 216 , all as described below.

The back shell 216 also includes a plurality of integrally molded, forwardly and upwardly extending hooks 240 ( FIG. 21 ) spaced from each other about the perimeter of the upper portion 218 of the back shell. A central or lumbar portion 242 is positioned vertically between the upper portion 218 and the lower portion 220 of the back shell 216 and includes a plurality of transversely extending slots 244 that cooperate to form a plurality of transversely extending ribs 246 therebetween. . The slots 244 cooperate to provide additional flexibility to the back shell 216 at their location. A pair of transverse ribs 246 cooperate with vertically extending ribs 248 which are integrally formed with the former and are located at approximately the transverse midpoint of the former. As the back assembly 18 is moved from the upright position E to the reclined position F as described below, the vertical ribs 248 act to tie the transverse ribs 246 together and reduce the Vertical expansion between the latter. The plurality of transversely spaced reinforcement ribs 250 extend longitudinally along the vertical length of the back shell 216 between the lower portion 220 and the middle portion 242 . Note here that the depth of each rib 250 increases along each rib 250 from the middle portion 242 to the lower portion 220 such that the overall rigidity of the back shell 216 increases along the length of the rib 250 .

The back shell 216 ( FIGS. 20A and 20B ) also includes a pair of rearwardly extending, integrally molded pivot bosses 252 which form part of an upper back pivot assembly 254 . Back pivot assembly 254 ( FIGS. 22-24B ) includes pivot bosses 252 of back shell 216 , a pair of cover members 256 surrounding respective pivot bosses 252 , track members 258 and a mechanical fastening assembly 260 . Each pivot boss 252 includes a pair of side walls 262 and a rearwardly concave seating surface 264 having a vertically elongated pivot slot 266 extending therethrough. Each cover member 256 is shaped to closely accommodate a corresponding pivot boss 252, and includes a plurality of side walls 268 corresponding to side walls 262, and a rearwardly concave bearing surface 270 including A vertically elongated pivot slot 272 is adapted to align with the slot 266 of the corresponding pivot boss 252 . The track member 258 includes a central portion 274 extending laterally along and abutting the top frame portion 204 of the back frame assembly 200, and a pair of arcuate bearing surfaces 276 at ends thereof. Specifically, central portion 274 includes a first portion 278 abutting a front surface of top frame portion 204 and a second portion 280 , wherein first portion 278 abuts a front surface of top frame portion 204 and second portion 280 abuts a top surface of top frame portion 204 . Each bearing surface 276 includes an aperture 282 extending therethrough that aligns with a corresponding sleeve member 284 integral with the back frame assembly 200 .

In assembly, the cover member 256 is positioned about the corresponding pivot boss 252 of the back shell 216 and is operably positioned between the back shell 216 and the track member 258 such that the bearing surface 270 is sandwiched by the corresponding pivot boss. Between the seating surface 264 of the boss 252 and a bearing surface 276 . The mechanical fastening assemblies 260 each include a bolt 286 that secures the circular abutment surface 288 of the bearing washer 290 in sliding engagement with the inner surface 292 of the corresponding pivot boss 252 and with the corresponding inner surface 292 of the back shell 216. Threaded engagement of sleeve member 284 . In operation, upper back pivot assembly 254 allows back support assembly 202 to pivot relative to back frame assembly about pivot axis 296 ( FIG. 18 ) in direction 294 ( FIG. 19 ).

The back support assembly 202 ( FIGS. 20A and 20B ) also includes a flexibly resilient comfort member 298 ( FIGS. 26A and 26B ) that attaches to the back shell 216 and slidably supports a lumbar support assembly 300 . The comfort component 298 includes an upper portion 302, a lower portion 304, a pair of side portions 306, a front surface 308, and a rear surface 310, wherein the upper portion 302, the lower portion 304, and the side portions 306 cooperate to form an aperture 312 that receives the lumbar support. Component 300 is therein. As best shown in FIGS. 20B and 25 , comfort component 298 includes a plurality of box-shaped couplings 314 spaced from one another about the perimeter of upper portion 302 , extending rearwardly from rear surface 310 . Each box coupling 314 includes a pair of side walls 316 and a top wall 318 that cooperate to form an interior space 320 . A bar 322 extends between side walls 316 and is spaced from rear surface 310 . When assembled, the comfort component 298 is secured to the back shell 216 by aligning and vertically inserting the hooks 240 ( FIG. 23 ) of the back shell 216 into the interior space 320 of each box coupling 314 until The hooks 240 engage corresponding rods 322 . Note here that the front surface 224 of the back shell 216 and the rear surface 310 of the comfort component 298 are free of holes or apertures near the hooks 240 and box coupling 314, thereby providing a smooth front surface 308 and increased Comfort for the seated user.

The comfort component 298 (FIGS. 26A and 26B) includes an integrally molded, longitudinally extending sleeve 324 extending rearwardly from the rear surface 310 and having a rectangular cross-sectional configuration. The lumbar support assembly 300 includes a forwardly laterally concave and forwardly vertically convex, pliable, resilient body portion 326 and an integral support portion 328 extending upwardly from the body portion 326 . In the illustrated example, the body portion 326 is shaped such that it tapers vertically along its height such that it generally follows the contour and shape of the aperture 312 of the comfort component 298 . Support portion 328 is slidably received within sleeve 324 of comfort component 298 such that lumbar support assembly 300 is vertically adjustable between a fully lowered position I and a fully raised position J relative to the remainder of back support assembly 202. between. The detent member 330 selectively engages a plurality of apertures 332 spaced apart from each other along the length of the support portion 328 to releasably secure the lumbar support assembly 300 at a selected position between the fully lowered position I and the fully raised position J. in vertical position. The pawl member 330 ( FIGS. 27A and 27B ) includes a housing portion 334 having engagement tabs 336 at an end thereof and offset rearwardly from an outer surface 338 of the housing portion 334 . A flexibly resilient finger 340 is centrally disposed within housing portion 334 and includes a rearwardly extending detent 342 .

When assembled, the detent member 330 ( FIG. 28 ) is positioned within the aperture 344 in the upper portion 302 of the comfort member 298 such that the outer surface 338 of the housing portion 334 of the detent member 330 is aligned with the front surface 308 of the comfort member 298 . coplanar, and such that the engagement tab 336 of the shell portion 334 abuts the rear surface 310 of the comfort component 298 . The support portion 328 of the lumbar support assembly 300 is then positioned within the sleeve 324 of the comfort member 298 such that the sleeve 324 can slide therein and the detent 342 is selectively engageable with the aperture 332, thereby allowing the user to optimize the recline. The position of the lumbar assembly 300 relative to the overall back support assembly 202 . Specifically, the main body portion 326 of the lumbar support assembly 300 includes a pair of outwardly extending, integral handle portions 346 ( FIGS. 29A and 29B ), each having a C-shaped cross-sectional configuration defining a channel 348 therein, which The side edge 222 of the backrest shell 216 and the corresponding side edge 306 of the comfort part 298 are surrounded and guided along them. Alternatively, a lumbar support assembly 300c (Fig. 30) is provided wherein the main body portion 326c and the support portion 328c are integrally formed and the handle 346c is formed separately from the main body portion 326c and attached thereto. In an alternative embodiment, each handle 346c includes a pair of blades 350c that are received in corresponding pockets 352c of the body portion 326c. Each vane 350c includes a pair of snap tabs 354c spaced from one another along its length for snap-fit engagement with an edge of one of the plurality of apertures 356c in the body portion 326c.

In operation, the user adjusts the lumbar support assemblies 300, 300c relative to each other by grasping one or both of the handle portions 346, 346c and sliding the handle assemblies 346, 346c in a vertical direction along the comfort member 298 and the back shell 298. The relative vertical position of the back shell 216. A stop tab 358 is integrally formed within the distal end 360 and is offset therefrom to engage the end wall of the sleeve 324 of the comfort component 298 to limit the movement of the support portion 328 of the lumbar support assembly 300 relative to the comfort component 298. The vertical downward travel of the sleeve 324.

The back assembly 202 ( FIGS. 20A and 20B ) also includes an upholstery member 362 having an upper portion 364 and a lower portion 366 , wherein the lower portion 366 tapers along its vertical length to correspond to the overall shape and taper of the back shell 216 and comfort member 298 .

The back support assembly 202 also includes an exterior cover assembly 400 (FIG. 31) that houses the comfort component 298, the lumbar support assembly 300, and the upholstery component 362 therein. In the illustrated example, the cover assembly 400 comprises a fabric material and includes a front side 402 ( FIG. 32A ) and a rear side 404 that are stitched together along their respective side edges to form a first pocket 406 having a first interior Or inner space 408, it receives comfort component 298 and cushion component 362 in it, and petal portion 410, it is sewn to rear side 404 and cooperates with it to form second pocket 412, and it has second interior or inner space 413 (FIG. 32D), which receives the lumbar support assembly 300 therein.

In assembly, the first pocket 406 ( FIG. 32A ) is formed by attaching the respective side edges of the front side 402 and the back side 404 to each other (for example, by sewing or other methods suitable for the materials from which the sheath assembly 400 is made) ( FIG. 32A ), and A first interior space 408 is defined. One edge of the petal portion 410 is then secured to the lower end of the rear side 404 . Thereafter, in the illustrated example, the combination of back shell 216 and upholstery component 362 is inserted into interior space 408 of first pocket 406 via aperture 415 in rear side 404 ( FIG. 32B ). The exterior trim cover assembly 400 is stretched over the upholstery component 362 and around the comfort component 298 and secured to the comfort component 298 by a plurality of apertures 420 that receive upwardly extending hook components 424 ( FIG. 33 ) therethrough. Alternatively, sleeve assembly 400 may be configured such that aperture 420 is positioned to simultaneously receive T-shaped attachment member 422 therethrough. In the illustrated example, the attachment member 422 and the hook member 424 are integrally formed with the comfort member 298 . Each attachment member 422 is provided with a T-section or bollard configuration having a first portion 428 extending rearward at right angles from a recess 429 in the rear surface 310 of the comfort member 298, and a pair of second portions. Portions 430 are located at the distal end of the first portion 428 and extend outwardly from the distal end opposite each other. One of the second portions 430 cooperates with the first portion 428 to form an angled engagement surface 432 . The recess 429 defines a rim 434 at its periphery.

Cover assembly 400 is further secured to comfort member 298 by a drawstring 436 that extends through a drawstring channel 438 of cover assembly 400 and is secured to attachment member 422 . Specifically, and as shown most clearly among FIGS. Attachment part 422 . When assembled, the drawstring 436 and drawstring channel 438 are guided about a plurality of guide hooks 439 ( FIG. 26B ) disposed around the perimeter of the comfort component 298 and integrally formed therewith. The pull cord 436 is wound around the associated attachment member 422 such that the tension of the draw cord 436 around the attachment member 422 forces the draw cord 436 against the engagement surface 432 on the side bent toward the recess 429, thereby forcing the tension of the draw cord 436. A portion enters the recess 429 and engages at least a portion of the edge 434 of the recess 429 to achieve increased frictional engagement between the drawstring 436 and the comfort component 298 . Figures 351 and 35J illustrate alternative paths that drawstring 436 may take around attachment member 422 relative to the steps shown in Figures 34G and 34H, respectively.

Then, the lumbar support assembly 300 (Figure 32C) is aligned with the assembly of the cover assembly 400, the cushion component 362 and the comfort component 298, so that the main body portion 326 of the lumbar support assembly 300 is located near the middle section 414 of the cover assembly 400, Support portion 328 and comfort component 298 of assembly 300 are coupled as described above. Flap portion 410 ( FIG. 32D ) is then folded over lumbar assembly 300 , creating second pocket 412 with interior space 413 . A distal edge 442 of the petal portion 410 is attached to the comfort member 298 by a plurality of apertures 444 within the petal portion 410 through which the hooks 424 pass to receive the hooks 424 . The distal edge 442 may also be sewn onto the rear side 404 of the sheath assembly 400 . In the illustrated example, the side edges 446 of the petal portion 410 are not attached to the rest of the cover assembly 400, so that the side edges 446 cooperate with the rest of the cover assembly 400 to form a plurality of grooves 448, the waist assembly 300 The handle portion 346 extends through the slots. The second pocket 412 is configured such that the lumbar support assembly 300 is vertically adjustable therein. The assembly of cover assembly 400 , cushion component 362 , comfort component 298 , and lumbar support assembly 300 is then attached to back shell 216 .

Reference numeral 18d (Fig. 36) generally designates an alternative embodiment of a backrest assembly. The backrest assembly 18d is similar to the previously described backrest assembly 18, so like parts appearing in FIGS. 20A and 20B and FIGS. d". The back assembly 18d includes a back frame assembly 200d, a back shell 216d, and an exterior trim assembly 400d. In the illustrated example, the back shell 216d includes a generally pliable outer peripheral portion 450d ( FIGS. 37 and 38 ), and a significantly less pliable rear portion 452d to which the peripheral portion 450d is attached. on it. The rear portion 452d includes a plurality of transversely extending, vertically spaced apart slots 454d that cooperate to define slats 456d therebetween. The perimeter portion 450d and the rear portion 452d cooperate to form an outwardly facing opening 458d that extends around the perimeter of the back shell 216d. The rear portion 452d includes a plurality of ribs 46Od that are spaced apart from one another about the opening 458d and that serve to secure the cover assembly 40Od to the back shell 216d as described below.

The sleeve assembly 400d includes a fabric sleeve 462d and a retaining member 464d extending around a peripheral edge 466d of the fabric sleeve 462d. The fabric cover 462d includes a front surface 468d and a rear surface 470d, and preferably comprises a material that is bendable in at least one of a longitudinal direction and a transverse direction. As shown most clearly in FIG. 39, the retaining member 464d is annular and includes a plurality of widened portions 472d each having a rectangular cross-sectional configuration connected with a plurality of narrowed corners each having a circular cross-sectional configuration. Portions 474d are separated from each other. Each widened portion 472d includes a plurality of apertures 476d spaced from one another along its length and adapted to engage ribs 460d of back shell 216d as described below. The retaining member 464d is constructed of a relatively pliable plastic so that the retaining member 464d can be turned inside out, as shown in FIG. 40 .

When assembled, the retaining member 464d is secured to the rear surface 470d of the sleeve 462d such that the sleeve 462d is rotationally fixed with the widened portion 472d and such that the sleeve 462d does not extend along the narrowed corner portion 474d tangential to the narrowed portion. The line of the longitudinal axis of the narrow corner portion 474d is fixed in rotation. In this example, retaining member 464d (FIG. 41) is stitched around peripheral edge 466d of sleeve 462d, with the stitching being stitched through widened portion 472d and around narrowed corner portion 474d. The sleeve assembly 400d of the retaining member 464d and sleeve 462d is aligned with the back shell 216d, and the peripheral edge 466d of the sleeve 462d surrounds the back shell 216d such that the inside of the retaining member 464d is turned inside out. The retention member 464d is then inserted into the opening or slot 458d such that the tension of the fabric cover 462d stretched across the back shell 216d keeps the retention member 464d positively engaged within the slot 458d. Ribs 460d of back shell 216d engage corresponding apertures 476d of retaining member 464d to further secure retaining member 464d within slot 458d. Note here that the stitching of the attachment sleeve 462d to the retaining member 464d allows the narrowed corner portion 474d of the retaining member 464d to rotate freely relative to the sleeve 462d, thereby reducing aesthetic anomalies adjacent the corners of the sleeve 462d, Such as bunching or hyperstretching of fabric patterns.

Seat assembly 16 and back assembly 18 are operably coupled to and controlled by control assembly 14 ( FIG. 42 ) and control input assembly 500 . The control assembly 14 (FIGS. 43-45) includes a housing or base structure or ground structure 502 that includes a front wall 504, a rear wall 506, a pair of side walls 508, and a bottom wall 510 that are integrally formed with one another and cooperate to form An internal space 512 opening upwards. Bottom wall 510 includes an aperture 514 centrally located therein, as described below. The base structure 502 further defines an upper and forward pivot point 516, a lower and forward pivot point 518, and an upper and rearward pivot point 540, wherein the control assembly 14 also includes a seat that supports the seat assembly 16. Support structure 522 . In the illustrated example, the seat support structure 522 has a generally U-shaped plan configuration that includes a pair of forwardly extending arm portions 524 that each include a forwardly located pivot aperture 526 that passes through the pivot axis. Rod 528 is pivotally secured to base structure 502 for pivotal movement about upper and forward pivot point 516 . The seat support structure 522 also includes a rear portion 530 that extends laterally between the arm portions 524 and cooperates therewith to form an interior volume 532 within which the base structure 502 is received. Rear portion 530 includes a pair of rearwardly extending arm mounting portions 534 to which arm assembly 20 is attached as described below. Seat support structure 522 also includes control input assembly mounting portion 536 to which control input assembly 500 is mounted. Seat support structure 522 also includes a pair of bushing assemblies 538 that cooperate to define pivot point 540 .

The control assembly 14 also includes a back support structure 542 having a generally U-shaped plan configuration and including a pair of forwardly extending arm portions 544 each including a pivot aperture 546 and pivotable by a pivot shaft 548 Rotationally coupled to the base structure 502 such that the back support structure 542 pivots about the pivot point 518 below and forward. The back support structure 542 includes a rear portion 550 that cooperates with the arm portion 544 to define an interior volume 552 that receives the base structure 502 therein. The back support structure 542 also includes a pair of pivot apertures 554 disposed along its length that cooperate to define a pivot point 556 . Note here that in some cases at least a portion of back frame assembly 200 may be included as part of back support structure 542 .

Control assembly 14 also includes a plurality of control linkages 558 each having a first end 560 pivotally coupled to seat support structure 522 by a pair of pivot pins 562 for pivoting about pivot point 540, and a pair of pivot pins 562 for pivoting about pivot point 540. The pivot pin 566 is pivotally coupled to a corresponding pivot aperture 554 of the back support structure 542 to pivot the second end 564 about the pivot point 556 . In operation, the control linkage 558 controls the movement of the seat support structure 522 relative to the back support structure 542 when the chair assembly is moved to the reclined position, and specifically controls the rate of recline thereof, as described below.

As best shown in FIGS. 46A and 46B , the bottom frame portion 206 of the back frame assembly 200 is configured to connect to the back support structure 542 via a quick connect device 568 . Each arm portion 544 of the back support structure 542 includes a mounting aperture 570 at a proximal end 572 thereof. In the illustrated example, the quick connect arrangement 568 includes an arrangement of the bottom frame portion 206 of the back frame assembly 200 that includes a pair of forwardly extending coupler portions 574 that cooperate to define a channel therebetween. 576, the channel 576 receives the proximal end 572 of the arm portion 544 and the rear portion 550 therein. Each coupler portion 574 includes a downwardly extending sleeve 578 that is aligned with and received by a corresponding aperture 570 . A mechanical fastener, such as screw 580 , is then threaded into the threads of sleeve 578 , thereby allowing quick connection of back frame assembly 200 to control assembly 14 .

As shown most clearly in FIG. 47, the base structure 502, seat support structure 522, back support structure 542, and control linkage 558 cooperate to form a four-bar linkage assembly that supports the seat assembly 16, back assembly 18, and arm assembly 20. (figure 1). For ease of reference, the relevant pivot assembly associated with the four-bar linkage assembly of the control assembly 14 is referred to as follows: The upper and forward pivot point 516 between the base structure 502 and the base support structure 522 is referred to as the first Pivot point 516; between base structure 502 and backrest support structure 542 pivot point 518 below and forward is referred to as second pivot point 518; between first end 560 of control linkage 558 and seat support structure 522 The pivot point 540 between is referred to as the third pivot point 540; and, the pivot point 556 between the second end 564 of the control linkage 558 and the back support structure 542 is referred to as the fourth pivot point 556. In addition, FIG. 47 shows in dashed lines the components of the chair assembly 10 in the reclined position, wherein the reference numerals of the chair in the reclined position are indicated by "'".

In operation, the four-bar linkage assembly of the control assembly 14 cooperates to recline the seat assembly 16 from the upright position G to the reclined position H as the backrest assembly 18 is moved from the upright position E to the reclined position F, wherein the position E The upper and lower representations of F and F in FIG. 47 show that the upper and lower portions of the backrest assembly 18 recline as a single piece. Specifically, the control linkage 558 is configured and coupled to the seat support structure 522 and the back support structure 542 such that when the back support structure 542 pivots about the second pivot point 518, the seat support structure 522 pivots about the first pivot point 516 change. Preferably, the seat support structure 522 is rotated about the first pivot point 516 at a rate between about 1/3 and about 2/3 of the rate at which the back support structure 542 is rotated about the second pivot point 518, more preferably the seat The rate at which the support structure 522 rotates about the first pivot point 516 is about half the rate at which the back support structure 542 rotates about the second pivot point 518, and most preferably when the backrest assembly 18 is reclined from the fully upright position E to At an angle γ, which is about 18°, to the fully reclined position F, the seat assembly 16 reclines from the fully upright position G to an angle β, which is about 9°, to the fully reclined position H.

As shown most clearly in FIG. 47, the first pivot point 516 is above and in front of the second pivot point 518 when the chair assembly 10 is in the fully upright position or the fully reclined position because the seat assembly The base structure 502 remains fixed relative to the supporting floor surface 13 while the 10 is tilted back. The third pivot point 540 remains behind the first pivot point 516 and below its relative vertical height throughout the reclining motion of the chair assembly 10 . It is further noted here that throughout the reclining movement of the chair assembly 10, the distance between the first pivot point 516 and the second pivot point 518 remains greater than the distance between the third pivot point 540 and the fourth pivot point 556. distance. As shown most clearly in Figure 48, a longitudinally extending central axis 582 of the control linkage 558 forms an acute angle α with the seat support structure 522 when the chair assembly 10 is in the fully upright position, and when the chair assembly 10 is in the fully reclined position , they form an acute angle α'. It is noted here that the central axis 582 of the control linkage 558 will not rotate beyond normal alignment with the seat support structure 522 when the chair assembly 10 is moved between its fully upright and fully reclined positions.

With further reference to FIG. 49 , the back control link 584 includes a forward end 585 that is pivotally coupled or connected to the seat support structure 522 at a fifth pivot point 586 . The rear end 588 of the back control link 584 is connected to the lower portion 220 of the back shell 216 at a sixth pivot point 590 . The sixth pivot point 590 is optional, and the back control link 584 and the back shell 216 may also be rigidly secured to each other. Additionally, pivot point 590 may include a stop that limits rotation of back control linkage 584 relative to back housing 216 in the first and/or second rotational directions. For example, referring to FIG. 49 , the pivot point 590 may include a stop 592 that allows the lower portion 220 of the back shell 216 to rotate clockwise relative to the control linkage 584 . The above configuration allows the lumbar to become flatter if a rearward/horizontal force tending to reduce dimension D ₁ is applied to the lumbar portion of the back shell 216 . However, the stop 592 may be configured to prevent the lower portion 220 of the back shell 216 from rotating in a counterclockwise direction relative to the control linkage 584 ( FIG. 49 ). This causes the linkage control 584 and the lower portion 220 of the back shell 216 to rotate at the same angular rate as the user reclines in the chair by pushing on the upper portion of the back assembly 18 .

A cam link 594 is also pivotally coupled or connected to the seat support structure 522 for rotation about the pivot point or axis 586 . The cam link 594 has a curved lower cam surface 596 that slidably engages an upwardly facing cam surface 598 formed in the back support structure 542 . A pair of torsion springs 600 (see also FIG. 29A ) tend to increase the angular (FIG. 49) rotatably biases the back control link 584 and the cam link 594. The torsion springs 600 create a force that tends to rotate the control link 584 in a counterclockwise direction and at the same time turn the cam link 594 in a clockwise direction. Accordingly, the torsion springs 600 tend to increase the angle between the back control link 584 and the cam link 594 A stop 592 on the seat support structure 522 limits counterclockwise rotation of the back control linkage 584 to the position shown in FIG. 49 . This force may also bias the control linkage 584 into the stop 592 in a counterclockwise direction.

As discussed above, the back shell 216 is pliable, especially compared to the rigid back frame structure 200 . Also as discussed above, the back frame structure 200 is rigidly connected to the back support structure 542 and thus pivots with the back support structure 542 . The force generated by the torsion spring 600 pushes upwardly against the lower portion 220 of the back shell 216 . Also as discussed above, the slots 244 in the back shell structure 216 create additional flexibility in the lumbar support portion or region 242 of the back shell 216 . The force generated by the torsion spring 600 also tends to cause the lumbar portion 242 of the back shell 2126 to flex forward such that the lumbar portion 242 has a greater curvature than the area adjacent to the torsion spring 600 .

As discussed above, the position of the lumbar support assembly 300 is vertically adjustable. Vertical adjustment of the lumbar assembly 300 also adjusts the manner in which the back shell 216 bends/bends during recline of the chair back 18 . For example, when the lumbar assembly 300 is adjusted to an intermediate or neutral position, the curvature of the lumbar portion 242 (FIG. 49) of the back shell 216 is also intermediate or neutral. If the vertical position of the lumbar assembly 300 is adjusted, the angle (FIG. 50) is reduced, and the curvature of the waist portion 242 is reduced. As shown in Figure 50, this also results in the angle becomes larger, and the overall shape of the back shell 216 becomes relatively straight.

With further reference to FIG. 51, if the height of the lumbar support assembly 300 is set at an intermediate level (i.e., as in FIG. 49), and a user leans back, then by the linkages and structures 502, 522, 542, 558 and the pivot points The four-bar linkage defined by 516, 518, 540, 556 will be moved from the configuration of Fig. 49 to the configuration of Fig. 51 (as described above). This in turn results in an increased distance between pivot point 586 and cam surface 598 . This results in angular Increased from about 49.5° (FIG. 49) to about 59.9° (FIG. 51). As the spring rotates toward the open position, part of the energy stored in the spring is transferred to the back shell 216, thereby making the lumbar portion 220 of the back shell 216 more curved. In this manner, the back control linkage 584, cam linkage 594 and torsion spring 600 provide a greater curvature to the lumbar portion 242 to reduce the curvature of the user's back as the user leans back in the chair.

Furthermore, the distance D between the lumbar region or portion 242 and the seat 16 increases from 174 mm to 234 mm when the chair is tilted from the position of FIG. 49 to the position of FIG. 51 . As the backrest 18 is tilted from the position in FIG. 49 to the position in FIG. 51 , the dimension D ₁ between the lumbar portion 242 of the back shell 216 and the back frame structure 200 also increases. Thus, during reclining, while distance D increases somewhat, the increase in dimension D1 reduces the increase in dimension D as lumbar portion 242 _of back shell 216 is displaced forward relative to back frame 200 .

Referring again to FIG. 49 , when the user 606 is seated in the upright position, the spine 604 of the seated user 606 tends to bend forward by a first amount in the lumbar region 608 . As the user 606 leans back from the position of FIG. 49 to the position of FIG. 51 , the curvature of the lumbar region 608 tends to increase, and the user's spine 604 will also rotate a little around the hip joint 610 relative to the user's femur 612 . The increase in dimension D and the curvature of the lumbar portion 242 of the back shell 216 ensures that the user's hip joints 610 and femur 612 do not slide on the seat 16 while also accommodating the lumbar region 608 of the user's spine 604. radian.

As discussed above, FIG. 50 shows the chair back 18 in an upright position with the lumbar portion 242 of the back shell 216 adjusted to a straight position. If the chair back 18 is tilted from the position of FIG. 50 to the position of FIG. 52, both the back control link 584 and the cam link 594 rotate in a clockwise direction. However, the cam linkage 594 rotates at a slightly higher rate, the angle So from 31.4° to 35.9°. The distance D changes from 202 mm to 265 mm, while the angle From 24.2° to 24.1°.

With further reference to Figure 52A, if the chair back 18 is reclined and the lumbar adjustment is set to high, the angle That is 93.6°, and the distance D is 202mm.

Accordingly, when the chair back 18 is reclined rearwardly, the back shell 216 flexes. However, if the curvature is initially adjusted to a higher level, the increased curvature of the lumbar portion 242 from the upright to the reclined position is significantly greater. This is an arrangement that takes into account the fact that if the user's back is initially in a relatively flat state when sitting upright, the curvature of the user's back will not increase as much when the user leans back. To reiterate: If the user's back is relatively straight in the upright position, the user's back will remain relatively straight even when reclined, although the arc increases slightly from the upright position to the reclined position. Conversely, if a user's back is significantly curved in an upright position, the increase in curvature of the lumbar region when the user leans back will be higher than for a user whose back is initially relatively straight.

A pair of spring assemblies 614 ( FIGS. 43 and 44 ) bias the backrest assembly 18 ( FIG. 4 ) from the reclined position F toward the upright position E. As shown in FIG. As best shown in FIG. 45 , each spring assembly 614 includes a cylindrical housing 616 having a first end 618 and a second end 620 . Each spring assembly 614 also includes a compression coil spring 622 , a first coupling 624 and a second coupling 626 . In the illustrated example, the first coupling member 624 is secured to the first end 618 of the housing 616 , while the second coupling member 626 is secured to a rod member 628 extending through a coil spring 622 . A washer 630 is secured to the distal end of the rod member 628 and abuts one end of the coil spring 622 , while the other end of the coil spring 622 abuts the second end 620 of the housing 616 . The first coupling member 624 is pivotally secured to the back support structure 542 by a pivot pin 632 received in a pivot aperture 636 of the back support structure 542 for pivotal movement about a pivot point 634 The second coupling member 626 is pivotally coupled to the moment arm displacement assembly 638 ( FIGS. 53-55 ) via a shaft 640 to pivot about a pivot point 642 . The moment arm displacement assembly 638 is adapted to move the bias or spring assembly 614 from a low tension setting (FIG. 57A) to a high tension setting (FIG. 58A), in which the bias assembly 614 is applied to the backrest assembly 18. The force is increased relative to the low tension setting.

As shown in FIGS. 53-56, the moment arm displacement assembly 638 includes: an adjustment assembly 644; Assembly 614 moves between low and high tension settings; and adjustment assist assembly 648, which is adapted to reduce the user's movement of moment arm displacement assembly 638 from a low tension setting to a high tension setting as described below. The magnitude of the input force applied to the control input assembly 500 .

The adjustment assembly 644 includes a pivot pin 650 that includes a threaded aperture that receives a threaded adjustment shaft 652 therein. Adjustment shaft 652 includes a first end 654 and a second end 656, wherein first end 654 extends through aperture 514 of base structure 502 and is guided by bearing assembly 660 to pivot about a longitudinal axis. Pivot pin 650 is supported by base structure 502 (FIG. 44) via a linkage assembly 662 comprising: a pair of linkage arms 664 each having a first end 666 supported by a pivot the pin 632 is pivotally coupled to the second coupling member 626; and the second end 668 is pivotally coupled by a pivot pin 670 pivotally received in a pivot aperture 672 of the base structure 502 to the base structure 502 to pivot about a pivot point 674; and an aperture 675 that receives a corresponding end of the pivot pin 650. Pivot pin 650 is pivotally coupled to linkage arm 664 along its length.

The moment arm displacement linkage assembly 638 includes a first drive shaft 676 extending between the control input assembly 500 and a first helical gear assembly 678 , and extending between the first helical gear assembly 678 and a second helical gear assembly 682 and a second drive shaft 680 operatively coupling the two, wherein a second helical gear assembly 682 is connected to the adjustment shaft 652 . The first drive shaft 676 includes a first end 684 that is operatively coupled to the control input assembly 500 by a first universal joint assembly 686, while a second end 688 of the first drive shaft 676 is connected to the control input assembly 500 by a second universal joint assembly 690. Operably coupled to the first helical gear assembly 678 . In the illustrated example, the first end 684 of the first drive shaft 676 includes a female coupling portion 692 of the first gimbal assembly 686, and the second end 688 of the first drive shaft 676 includes the second gimbal A female coupling portion 694 of assembly 690 . The first bevel gear assembly 678 includes a housing assembly 696 that houses the first bevel gear 698 and the second bevel gear 700 therein. As shown, the first helical gear 698 includes a male coupling portion 702 integral with the second gimbal assembly 690 . First end 706 of second drive shaft 680 is coupled to first helical gear assembly 678 through third universal joint assembly 704 . The first end 706 of the second drive shaft 680 includes a female coupling portion 708 of the third gimbal assembly 704 . The second helical gear 700 includes a male coupling portion 710 with which the third gimbal assembly 704 is integral. The second end 712 of the second drive shaft 680 includes a plurality of longitudinally extending splines 714 that mate with corresponding longitudinally extending splines (not shown) of a coupler member 716 . Coupler member 716 couples second end 712 of second drive shaft 680 with second helical gear assembly 682 via fourth universal joint assembly 718 . The fourth gimbal assembly 718 includes a housing assembly 720 that houses: a first helical gear 722 coupled to the coupler member 716 by the fourth gimbal assembly 718 , and a helical gear fixed to the second end 656 of the adjustment shaft 652 The second helical gear 724 . Coupler member 716 includes a female coupling portion 726 that receives a male coupling portion 728 integral with first helical gear 722 .

When assembled, the adjustment assembly 644 ( FIGS. 53 and 54 ) of the moment arm displacement assembly 638 is operably supported by the base structure 502 , while the control input assembly 500 ( FIG. 42 ) is operatively supported by the control input assembly mounting portion of the seat support structure 522 . 536 (FIG. 44) is operatively supported. As a result, as the seat support structure 522 is moved between the fully upright position G and the fully reclined position H, the relative angle and distance between the control input assembly 500 and the adjustment assembly 644 of the moment arm displacement assembly 638 changes. The third and fourth gimbal assemblies 704, 718 and splines 714 cooperate with the arrangement of the coupler 716 to compensate for these relative changes in angles and distances.

The moment arm displacement assembly 638 (Figs. 53 and 54) functions to adjust the biasing assembly 614 between low tension and high tension settings (Figs. 57A-58B). Specifically, Figure 57A shows the biasing assembly 614 at a low tension setting with the chair assembly 10 in an upright position, Figure 57B shows the biasing assembly at a low tension setting with the chair assembly 10 in a reclined position, Figure 58A The biasing assembly 614 is shown at the high tension setting with the chair assembly 10 in the upright position, while FIG. 58B shows the biasing assembly at the high tension setting with the chair assembly 10 in the reclined position. The distance 730 measured between the pivot point 642 and the second end 620 of the housing 616 of the spring assembly 614 is used as the distance 730 applied when the moment arm displacement assembly 638 is placed in the low tension setting and the chair assembly 10 is in the upright position. A reference to the amount of compression of the spring assembly 614. Distance 730' (FIG. 58A) comparatively illustrates the incremental compressive force applied to spring assembly 614 when moment arm displacement assembly 638 is in the high tension setting and chair assembly 10 is in the upright position. The user adjusts the amount of force exerted by the biasing assembly 614 on the back support structure 542 by moving the moment arm displacement assembly 638 from a low tension setting to a high tension setting. Specifically, the operator drives the adjustment shaft 652 of the adjustment assembly 644 to rotate through the moment arm displacement linkage assembly 646 with the input to the control input assembly 500, thereby causing the pivot shaft 650 to travel along the length of the adjustment shaft 654, thereby The compressive force exerted on spring assembly 614 is varied during pivot shaft 650 is articulated relative to base structure 502 . The pivot shaft 650 travels within a slot 732 disposed within a side plate member 734 attached to an associated side wall 508 of the base structure 502 . Note here that the distance 730' is greater when the moment arm displacement assembly 638 is at the high tension setting and the chair assembly 10 is in the upright position than when the moment arm displacement assembly 638 is at the low tension setting and the chair assembly 10 is in the upright position The distance 730 of , thus showing that when the moment arm displacement member is at the high tension setting, the compressive force exerted on the spring assembly 614 is greater than at the low tension setting. Similarly, distance 736' (FIG. 58B) is greater than distance 736 (FIG. 57B), causing the biasing force exerted by biasing assembly 614 to increase and force backrest assembly 18 from the reclined position to the upright position. Note here that a change in the biasing force applied by the biasing assembly 614 corresponds to a change in the biasing torque applied about the second pivot point 518 and, in some configurations, does not change the length or biasing of the biasing assembly 614. Pressure can also change bias torque.

59 is a graph of the amount of torque applied about the second pivot point 518 that forces the back support structure 542 from the reclined position to the upright position as the back support structure 542 is moved between the reclined position and the upright position. In the illustrated example, when the back support structure 542 is in the upright position and the moment arm displacement assembly 638 is in the low tension setting, the biasing assembly 614 applies a torque of about 652 inch-pounds about the second pivot point 518, This compares to about 933 inch-pounds when the back support structure 542 is in the reclined position and the moment arm displacement assembly 638 is in the low tension setting, resulting in a change of about 43%. Similarly, when the back support structure 542 is in the upright position and the moment arm displacement assembly 638 is in the high tension setting, the bias assembly 614 applies a torque of about 1.47E+03 inch-pounds about the second pivot point 518, and When the back support structure 542 is in the reclined position and the moment arm displacement assembly 638 is in the high tension setting it is about 2.58E+03 in-lbs, resulting in a variation of about 75%. As the back support structure 542 is moved between the upright and reclined positions, the amount of torque applied by the biasing assembly 614 produces a considerable This allows the overall chair assembly 10 to provide proper forward back support for users of different heights and weights.

Adjustment assist assembly 648 (FIGS. 53 and 54) assists the operator in moving moment arm displacement assembly 638 from a high tension setting to a low tension setting. Adjustment assist assembly 648 includes coil spring 738 secured to front wall 504 of base structure 502 with mounting structure 740, and snap member 742 that extends around shaft 632 secured to link arm 664 and includes a snap Buckle portion 744 that defines an aperture 746 that captures a free end 748 of coil spring 738 . The coil spring 738 applies a force F in an upward vertical direction on the snap member 742 and the shaft 632, as well as on the shaft 632 attached to the linkage arm 664, thereby reducing the need for the user to move the moment arm displacement assembly 638 from The input force that must be applied to the control input assembly 500 to move from the low tension setting to the high tension setting.

As noted above, the seat assembly 16 ( FIG. 3 ) is longitudinally movable relative to the control assembly 14 between a retracted position C and a deployed position D. As shown in FIG. As shown most clearly in FIGS. 60 and 61 , direct drive assembly 1562 includes drive assembly 1564 and linkage assembly 1566 that couples control input assembly 500 to drive assembly 1564 , thereby allowing the user to adjust seat assembly 16 relative to The linear position of the control assembly 14. In the illustrated example, seat support plate 32 ( FIG. 42 ) includes C-shaped guide rails 38 that wrap around and slidably engage corresponding guide flanges 1570 of control plate 1572 of control assembly 14 . A pair of C-shaped, longitudinally extending connecting rails 1574 are positioned within corresponding rails 38 and coupled to seat support plate 32 . A pair of C-shaped bushing members 1576 extend longitudinally within the connecting rail 1574 and are positioned between the connecting rail 1574 and the guide flange 1570 . Drive assembly 1564 includes a rack member 1578 having a plurality of downwardly extending teeth 1580 . Drive assembly 1564 also includes a rack guide 1582 having a C-shaped cross-sectional configuration that defines a channel 1584 that slidably receives rack member 1578 therein. Rack guide 1582 includes a clearance slot 1586 along its length that cooperatively receives bearing member 1588 therein, wherein bearing member 1588 shown in phantom shows bearing member 1588 and the rack guide Assembly alignment between slots 1586 of 1582 , while additionally, bearing components shown in solid lines illustrate assembly alignment between bearing component 1588 and rack component 1578 . Alternatively, bearing member 1588 may be formed as an integral part with rack guide 1582 . Drive assembly 1564 also includes a drive shaft 1590 having a first end 1592 universally coupled with control input assembly 500 and a second end 1594 having a plurality of teeth 1596 radially spaced from one another. In assembly, seat support plate 32 is slidably coupled with control plate 1572 as described above, with rack member 1578 secured to the underside of seat support plate 32 and rack guide 1582 secured to control plate 1572 in an upwardly opening channel 1598 . In operation, an input force applied by a user to control input assembly 500 is transmitted through linkage assembly 1566 to drive assembly 1564, thereby driving teeth 1596 of drive shaft 1590 against teeth 1580 of rack member 1578 and causing the rack Member 1578 and seat support plate 32 slide relative to rack guide 1582 and control plate 1572 .

With further reference to FIGS. 62-64 , the chair assembly 10 includes a height adjustment assembly 1600 that allows vertical adjustment of the seat 16 and backrest 18 relative to the base assembly 12 . The height adjustment assembly 1600 includes a pneumatic cylinder 28 arranged vertically in the central column 26 of the base assembly 12 in a known manner.

A bracket structure 1602 is secured to the housing or base structure 502, and the upper end portion 1604 of the pneumatic cylinder 28 is received in an opening 1606 in the base structure 502 (Fig. 64) in known manner. The pneumatic cylinder 28 includes an adjustment valve 1608 that can be moved down to release the pneumatic cylinder 28 to provide height adjustment. Bell crank 1610 has an upwardly extending arm 1630 and a horizontally extending arm 1640 configured to engage release valve 1608 of pneumatic cylinder 28 . Bell crank 1610 is rotatably mounted to bracket 1602 . Cable assembly 1612 operably interconnects bell crank 1610 with adjustment wheel/rod 1620 . Cable assembly 1612 includes an inner cable 1614 and an outer cable or sheath 1616 . Outer sheath 1616 includes a ball fitting 1618 that is rotatably received in a ball socket 1622 formed in bracket 1602 . A second ball fitting 1624 is connected to an end 1626 of the inner cable 1614 . Second ball fitting 1624 is rotatably received in second ball socket 1628 of upwardly extending arm 1630 of bell crank 1610 to allow rotational movement of the cable end during height adjustment.

A second or outer end portion 1632 of the inner cable 1614 wraps around the wheel 1620 and an end fitting 1634 is connected to the inner cable 1614 . Tension spring 1636 is connected to end fitting 1634 and seat structure at 1638. The spring 1636 creates tension in one direction on the inner cable 1614, and when the valve 1608 is released, the cable 1614 is also displaced in the same direction to turn the bell crank 1610. Spring 1636 does not produce enough force to actuate valve 1608 , but spring 1636 produces enough force to bias arm 1640 of bell crank 1610 into contact with valve 1608 . In this way, false play or looseness due to component tolerances is eliminated. During operation, the user manually turns the adjustment wheel 1620 to create tension on the inner cable 1614 . This causes bell crank 1610 to rotate causing arm 1640 of bell crank 1610 to press against and actuate valve 1608 of pneumatic cylinder 28 . An internal spring (not shown) of pneumatic cylinder 28 biases valve 1608 upward, moving valve 1608 to a non-actuated position after adjustment wheel 1620 is released.

The control input assembly 500 (FIGS. 42 and 65-67) includes a first control input assembly 1700 and a second control input assembly 1702, each adapted to communicate input from a user to the chair member and chair member to which they are coupled. Functions, chair components and functions are housed within housing assembly 1704 . Control input assembly 500 includes anti-backdrive assembly 1706 , overload clutch assembly 1708 , and knob 1710 . Anti-backdrive mechanism or assembly 1706 that prevents direct drive assembly 1562 ( FIGS. 60 and 61 ) and seat assembly 16 from being moved between retracted and deployed positions C, D without input from control assembly 1700 drive. Anti-backdrive assembly 1706 is received within interior 1712 of housing assembly 1704 and includes adapter 1714 including at one end a male portion 1716 of a gimbal adapter coupled to second end 1594 of drive shaft 1590 ( FIG. 61 ), And includes a splined connector 1717 at the other end. Cam member 1718 is coupled to adapter 1714 by clutch member 1720 . Specifically, cam member 1718 includes a splined end 1722 coupled for rotation with knob 1710 and a cam end 1724 having an outer cam surface 1726 . Clutch member 1720 ( FIG. 66B ) includes a pair of inwardly disposed splines 1723 that slidably engage spline connector 1717 having a cam surface 1730 that mates with an outer cam surface of cam member 1718 as described below. 1726 camming engagement. Clutch member 1720 has a conical clutch surface 1719 received in engagement therewith by a locking ring 1732 locked for rotation relative to housing assembly 1704 and includes a conical clutch surface 1721 corresponding to clutch surface 1719 of clutch member 1720 , which cooperate to form a cone clutch. Coil spring 1734 biases clutch member 1720 into engagement with locking ring 1732 .

When there is no input, the biasing spring 1734 forces the conical surface of the clutch member 1720 into engagement with the conical surface of the locking ring 1732, thereby preventing "kickback", or only in the absence of input from the first control input assembly 1700. Seat assembly 16 is adjusted between retracted and deployed positions C, D by applying a rearward or forward force to seat assembly 16 . In operation, an operator actuates direct drive assembly 1562 via first control input assembly 1700 to move seat assembly 16 between retracted and deployed positions C,D. Specifically, the rotational force applied by the user to the knob 1710 is transmitted from the knob 1710 to the cam member 1718 . As cam member 1718 rotates, outer cam surface 1726 of cam member 1718 acts on cam surface 1730 of clutch member 1720, thereby overcoming the biasing force of spring 1734 and forcing clutch member 1720 out of the engaged position, wherein clutch member 1720 is disengaged from the locking ring 1732. Rotational force is then communicated from cam member 1718 to clutch member 1720 to adapter 1714 , which is coupled to direct drive assembly 1562 via linkage assembly 1566 .

Note here that a small amount of tolerance in the first control input assembly 1700 allows slight movement (or "wobble") of the cam member 1718 both linearly and rotationally as the clutch member 1720 is moved between engaged and disengaged positions. A rotating annular damper element 1736 comprising thermoplastic elastomer (TPE) is located within interior 1712 of housing 1704 and is attached to clutch member 1720 . In the illustrated example, damping element 1736 is pressed against and frictionally engages the inner wall of housing assembly 1704 .

The first control input assembly 1700 also includes a second knob 1738 adapted to allow a user to adjust the vertical position of the chair assembly between a lowered position A and a raised position B as described below.

The second control input assembly 1702 is adapted to adjust the tension applied to the backrest assembly 18 during recline and to control the recline of the backrest assembly 18 . First knob 1740 is operatively coupled to moment arm displacement assembly 638 by moment arm displacement linkage assembly 646 . Specifically, the second control input assembly 1702 includes a male coupling portion 1742 that couples with the female gimbal coupling portion 692 ( FIGS. 53 and 55 ) of the shaft 676 of the moment arm displacement linkage assembly 646 .

The second knob 1760 is adapted to adjust the recline of the backrest assembly 18 via a cable assembly 1762 that operably couples the second knob 1760 to a variable backrest stop assembly 1764 (FIG. 67). Cable assembly 1762 includes a first cable structure 1766, a second cable structure 1768, and a cable tube 1770 extending therebetween that slidably receives an actuation cable 1772 therein. Cable 1772 includes a distal end 1774 that is fixed relative to base structure 502 and biased in a direction 1776 by coil spring 1778 . The variable backrest assembly 1764 includes a stop 1780 having a plurality of vertically graded steps 1782, a support bracket 1784 fixedly supported relative to the seat assembly 16, and a slide member 1786 slidably coupled to the support The bracket 1784 is slidable in a front-to-back direction 1788 and is fixedly coupled to the stop member 1780 by a pair of screws 1790 . The cable 1772 is clamped between the stop member 1780 and the slide member 1786 such that longitudinal movement of the cable 1772 causes the stop member 1780 to move in the fore-aft direction 1788 . In operation, the user adjusts the position of the stop member 1780 via an input to the second knob 1760 to adjust the possible back recline. As the back assembly 18 moves from the upright position to the reclined position, selected ones of the plurality of steps 1782 of the stop member 1780 contact the rear edge 1792 of the base structure 502 to limit the available back recline.

Reference numeral 1Oe (FIG. 68) generally refers to another embodiment of a chair assembly or seating arrangement. Since this seating arrangement 10e is similar to the previously described seating arrangement or chair assembly 10, parts similar to those appearing in Figures 1 and 2 and Figure 68 are designated by the same corresponding reference numerals, but with a suffix "e". In the example shown, the seating arrangement 1Oe includes a headrest assembly 2000 pivotably coupled to a backrest assembly 18e. The head restraint assembly 2000 includes a support assembly 2002 and a head restraint member 2004 . As best shown in FIGS. 69 and 70A , the support assembly 2002 includes a support 2006 pivotally coupled to the backrest assembly 18e by a first hinge arrangement 2008 . The support 2006 has a generally U-shaped configuration comprising a laterally extending base portion 2010 and a pair of upwardly extending arm portions 2012 . Each arm includes a vertical portion 2014 and a terminal portion 2016 extending upwardly and slightly forward from the associated vertical portion 2014 . The first articulation arrangement 2008 includes a pair of hinges 2018 that pivotally couple the support member 2006 to the back assembly 18e to rotate in a direction 2022 about a laterally extending first pivot axis 2020 . Each hinge 2018 comprises a friction lock type hinge, wherein the rotational position of the support 2006 relative to the back assembly 18e is held in place by friction within the hinge 2018 . Specifically, the hinge 2018 couples the support 2006 to the upper portion 218e of the back shell 216e (FIG. 71). In the example shown, back shell 216e includes grooves 2021 and comfort member 298e includes grooves 2023, each for receiving base portion 2010 therein. The support assembly 2002 also includes a support cover 2025 for covering the front of the base portion 2010, while a rear cover 2027 covers the back of the back shell 216e. In adjustment, friction within hinge 2018 is overcome by a user applying sufficient force to head restraint assembly 2000 . After adjustment, the force applied by the user is released and friction in the hinge 2018 maintains the support 2006 in the selected rotational position. Note that there is no external or independently releasable locking assembly to hold or secure the support member 2006 in a rotational position relative to the backrest assembly 18e.

The support assembly 2000 also includes a second articulation arrangement 2024 that includes a guide 2026 having a flat body 2028 and a pair of tubular ends 2030, each of which is Each has an outwardly opening aperture 2032 . The second hinge arrangement 2024 also includes a pair of friction locking type hinge arrangements 2033 ( FIG. 72 ) that rotatably couple the head restraint member 2004 to the support member 2006 extending laterally in a direction 2036 The second pivot axis 2034 rotates (FIG. 69). Each hinge arrangement 2033 ( FIG. 72 ) comprises a hinge 2038 comprising a first end 2040 press fit within an associated aperture 2032 of one of the ends 2030 of the guide 2026, and fixed non-rotatably; and a second end 2042 that is press-fitted within an aperture 2044 of one of the end portions 2016 of the arms 2012 of the support 2006 and fixed non-rotatably. The hinge arrangement 2033 allows the head restraint 2004 to pivot relative to the support 2006 about a second pivot axis 2034 . As mentioned above, each hinge arrangement 2033 comprises a friction locking type hinge, wherein the rotational position of the head restraint member 2004 is held in place by friction within the hinge arrangement 2033 . In adjustment, the frictional forces within the articulation 2033 are overcome by a sufficient force applied by the user to the head restraint member 2004 . After adjustment, the force applied by the user is released and friction within the articulation 2033 maintains the head restraint 2004 in the selected rotational position. Note that there is no external or independently releasable locking assembly to hold or secure the head restraint member 2004 in a rotational position relative to the support member 2006 . End cap 2046 is located within the end of aperture 2044 . The dual pivot adjustment that allows the headrest member 2004 and support member 2006 to pivot about the first pivot axis 2020 and the second pivot axis 2034 and reposition allows the headrest to be repositioned relative to the backrest assembly 18e and a person seated in the seating arrangement 10e in various positions and orientations, as further described below. Alternatively, the head restraint assembly may comprise a support with a single arm and/or a single hinge for coupling the support to the back assembly and/or a single hinge for coupling the head restraint to the support. Single hinge.

Head restraint 2004 is also vertically adjustably supported by support 2006 for adjustment in direction 2047 . In a first embodiment, a headrest member 2004 (FIG. 70A) includes: a frame member 2048; a sub-frame member 2050 releasably coupled to the frame member 2048; and a mesh fabric cover 2052, the mesh Fabric cover 2052 is attached to frame member 2048 by sub-frame member 2050 . Although a mesh fabric cover 2052 is included in this example, note that non-mesh fabrics and other materials can also be used. Sleeve 2052 includes a forward-facing support surface 2054 configured to support the head and/or neck of a seated user, and a wraparound lip 2056 extending rearwardly from support surface 2054 . A pair of horizontal frame or straps 2058 are positioned and secured along the top and bottom of the wrapping 2056 , while a pair of vertical straps or straps 2059 are positioned and secured along the sides of the flap 2056 . In assembly, collar 2056 ( FIG. 73 ) of sleeve 2052 wraps around the outer perimeter of subframe member 2050 , and attachment strip 2058 is coupled to the rear surface of subframe member 2050 . As best shown in FIGS. 73-75 , the horizontal mounting bars 2058 each have an arrow-shaped cross-sectional configuration including enlarged heads 2061 that engage spaced along the upper and lower edges of the subframe 2050 . The plurality of flat tabs 2063 and the plurality of configuration tabs 2065 engage, while the vertical mounting strip 2059 engages the plurality of flat tabs 2065 spaced along the side of the subframe 2058. The tension in the mesh fabric sleeve 2052 keeps the vertical attachment strip 2059 engaged with the flat boss 2065 and can hold it between the boss 2065 and the outer wall 2049 . Subframe 2050 is then releasably snap-coupled to frame member 2048 such that wrapping flange 2056 and attachment strip 2058 are sandwiched and hidden between subframe member 2050 and frame member 2048 .

In the second embodiment, the sub-frame 2050 and mesh fabric cover 2052 of the first embodiment shown in FIG. In assembly, a plurality of attachment strips 2057 secure the fabric cover 2055 to the trim ring 2051 with the foam piece 2053 sandwiched between the cover 2055 and the ring 2051 . Ring 2051 is then attached to frame 2048 such that attachment strip 2057 and the edges of fabric cover 2052 are sandwiched between trim ring 2051 and frame 2048 .

The frame member 2048 includes: a peripherally extending frame portion 2060 to which the sub-frame member 2050 is attached; and a vertically extending, forwardly convex arc-shaped central portion 2062 . The central portion 2062 (FIG. 70) comprises: a vertically extending elongated slot 2070; a first set of rearwardly facing, vertically spaced protrusions 2072; and a second set of rearwardly facing, vertically spaced protrusions 2074, the second set of Rearwardly facing, vertically spaced protrusions 2074 are located on opposite sides of the slot 2070 relative to the first set of protrusions 2072 . Note that the bumps of the first set of bumps 2072 offset the bumps of the second set of bumps 2074 in the vertical direction. A pair of fastening portions 2078 at ends thereof secure a pair of leaf springs 2076 to the planar portion 2028 of the guide 2026 . Each spring 2076 also includes an engagement portion 2080 positioned between the fastening portions 2078 and biased toward the first set of tabs 2072 and the second set of tabs 2074 . The attachment 2082 is attached to the guide 2026 by a pair of screws 2086 such that the central portion 2062 is slidably sandwiched between the guide 2026 and the attachment 2082 and the sliding motion is guided by spacers 2085 positioned with the slots 2070 . Sleeve 2083 snaps into and encloses the back of central portion 2062 .

In adjustment, the user adjusts the head restraint 2004 relative to the support assembly 2002 by applying an upward or downward force to the head restraint 2004, thereby vertically adjusting the head restraint 2004 in the vertical direction 2047 and causing the head restraint 2004 to rotate about Pivot area 2079 spaced from head restraint member 2004 and support assembly 2002 pivots. By engaging the engaging portion 2080 of one of the leaf springs 2028 with an associated set of protrusions 2072, 2074, the head restraint member 2004 is maintained in a selected vertical position. As mentioned above, the protrusions in the first set of protrusions 2072 and the second set of protrusions 2074 are vertically offset from each other so that only one set of protrusions is engaged by the spring 2076, thereby improving effective vertical adjustment of the head restraint member 2004 sex. As an option, by vertically offsetting the springs 2076 from each other when the tabs 2072, 2074 are aligned with each other, increased reinforcement of the head restraint 2004 as provided by the vertically offset tabs 2072, 2074 may be provided. Quantitative offset adjustability. In another embodiment, the tabs 2072, 2074 may be vertically offset from each other, and the spring 2076 may be vertically offset from each other.

The dual pivotal adjustment and vertical adjustability of the head restraint assembly 2000 allows the head restraint assembly 2000 to be positioned between a wide variety of points and assume many configurations to accommodate many different types of users in the manner shown in FIGS. 78A-78K. For example, the head restraint assembly 2000 can be adjusted between a forward position, such as that shown in FIG. 78I, and a rearward position, such as that shown in FIG. , and in the vertical direction, the headrest member 2004 is adjusted to a lowered position relative to the support assembly 2002, and in the rearward position, the headrest member 2004 is adjusted to the most elevated position relative to the support assembly 2002 in the vertical direction position and rotate the support assembly 2002 to a rearward position relative to the backrest assembly 18e. In these and other embodiments, the head restraint 2004 can rotate about the support assembly 2002 such that it makes physical contact with the support assembly 2002 or the backrest assembly 18e. For example, in the position shown in Figure 78I, the lower edge of the headrest member 2004 (as positioned) may be in contact with the front surface of the backrest assembly 18e, while in the position shown in Figure 78K, the lower edge of the headrest assembly 2004 Contact may be made with the rear surface of the backrest assembly 18e or the support assembly 2002 (as positioned).

In some embodiments, one or more stops may be placed within the back assembly 18e, the support assembly 2002, and/or the head restraint assembly 2000 to limit a particular position. For example, a stop 2100 (FIG. 78K) may be provided to prevent rotation of the support assembly 2002 beyond a rearward horizontal orientation. Similarly, a stop 2102 (FIG. 78G) may be provided to prevent the support assembly 2002 from rotating forward of a selected position.

In the foregoing description, those skilled in the art can easily understand that without departing from the disclosed concept, various alternative combinations can be made to the various components and elements of the present invention, and various modifications can be made to the present invention. The disclosed inventive concept has application to vehicle seating, stadium seating, home seating, theater seating, and the like. Such modifications are to be regarded as included in the appended claims unless those claims by their text expressly state otherwise.

Claims (33)

1. a kind of headrest assemblies for being adapted to be coupled to seat arrangement, including；

Support meanss, the support meanss are configured to may be pivotably coupled to the backrest module of seat arrangement, with around the first pivot Line moves pivotally；

Rest the head on part, the headrest part may be pivotably coupled to the support meanss, with around the separated with first pivotal line Two pivotal lines move pivotally；And

The headrest part is coupled to the support meanss by carriage, the carriage, and the carriage is constructed Into permission along curved path the headrest part is adjusted relative to the support meanss vertical sliding motion.

2. headrest assemblies according to claim 1, wherein the carriage is configured so as to fill when using described slide Put vertically adjust it is described headrest part when, the headrest part around with it is described headrest part and the headrest support at least one every The pivot area opened is pivoted.

3. headrest assemblies according to claim 2, wherein the carriage is configured so as to fill when using described slide Put when vertically adjusting the headrest part, the headrest part around with the headrest part and the pivot that separates of headrest support Area is pivoted.

4. the headrest assemblies described in any one in claim 1-3, wherein when relative to the back rest vertically During the regulation headrest part, the distance between first pivotal line and described second pivotal line are held substantially constant.

5. the headrest assemblies described in any one in claim 1-4, wherein the support meanss include the first friction Articulated mounting, the first friction articulated mounting is configured to make the support meanss may be pivotably coupled to the backrest module.

6. headrest assemblies according to claim 5, wherein the headrest part rubs articulated mounting pivotly by second It is coupled to the support meanss.

7. the headrest assemblies described in any one in claim 1-6, wherein the headrest part includes arcuation orbit portion, The arcuation orbit portion is slidably engaged by the support meanss.

8. the headrest assemblies described in any one in claim 1-7, wherein the support meanss are biased comprising spring Fastener, the fastener of spring bias engages the headrest assemblies using frictional force so that can multiple upright positions it Between be selectively adjusted the headrest assemblies relative to the backrest module.

9. headrest assemblies according to claim 8, wherein the headrest part includes multiple lock pins, the multiple lock pin is mutual The fastener that separates and can be biased by the spring is selectively engaged so that the headrest part be held in it is described vertical At position.

10. headrest assemblies according to claim 9, wherein the multiple lock pin is a pair of multiple lock pins, it is the pair of Multiple lock pins include more than first lock pin and more than second lock pin, the lock pin in more than first lock pin is by described the In more than two lock pin the lock pin skew so that when vertically adjusting the headrest, the fastener alternately with it is described More than first lock pin and more than second lock pin engagement.

11. the seat arrangement of the headrest assemblies described in any one in a kind of 1-10 including claim, and also include：

Portions component, the portions component is adapted to support user；And

Backrest module, the backrest module is operatively coupled to the portions component, and the backrest module is adapted to branch User is supportted, wherein the headrest assemblies are operatively coupled to the backrest module.

12. a kind of headrest assemblies for being adapted to be coupled to seat arrangement, including：

Support meanss, the support meanss are operatively configured to be coupled to the backrest module of seat arrangement；

Headrest part, the headrest part has arc support portion；And

Carriage, the carriage makes the supporting part of the headrest part be slidably coupled to the support meanss, So that causing the headrest part along curved path relative to the branch relative to part of being rested the head on described in the supporting part slidable adjustment Support arrangement is advanced.

13. headrest assemblies according to claim 12, wherein the carriage is configured so as to slide when using described When device vertically adjusts the headrest part, at least one of the headrest part in being supported with the headrest part and the headrest The pivot area separated is pivoted.

14. headrest assemblies according to claim 13, wherein the carriage is configured so as to slide when using described When device vertically adjusts the headrest part, the headrest part is around the pivot separated with the headrest part and headrest support Axle area is pivoted.

15. the headrest assemblies described in any one in claim 12-14, wherein be configured to can pivot for the support meanss It is coupled to the seat back of the body with turning, to be moved pivotally around the first pivotal line.

16. headrest assemblies according to claim 15, wherein the headrest part may be pivotably coupled to the support meanss, To be moved pivotally around the second pivoting point.

17. the headrest assemblies described in any one in claim 15 and 16, wherein the support meanss include first Rub articulated mounting, and the first friction articulated mounting is configured to make the support meanss may be pivotably coupled to the backrest group Part, to be moved pivotally around first pivotal line.

18. the headrest assemblies described in any one in claim 12-17, wherein the headrest part utilizes the second friction Articulated mounting may be pivotably coupled to the support meanss.

19. the headrest assemblies described in any one in claim 12-17, wherein the support meanss are inclined comprising spring The fastener of pressure, the fastener of the spring bias engages the headrest assemblies using frictional force so that the headrest assemblies structure Cause to be selectively adjusted relative to the backrest module between multiple upright positions.

20. headrest assemblies according to claim 19, wherein the headrest part includes multiple lock pins, the multiple lock pin is mutual The fastener that is spaced and can be biased by the spring is selectively engaged so that the headrest part be held in it is described vertical At position.

21. headrest assemblies according to claim 20, wherein the multiple lock pin is a pair of multiple lock pins, it is the pair of Multiple lock pins comprising more than first lock pin and more than second lock pin, the lock pin in more than first lock pin will be described In more than second lock pin the lock pin skew so that when vertically adjusting the headrest, the fastener alternately with institute State more than first lock pin and more than second lock pin engagement.

22. the seat arrangement of the headrest assemblies described in any one in a kind of 12-21 including claim, and also include：

Portions component, the portions component is adapted to support user；And

Backrest module, the backrest module is operatively coupled to the portions component, and the backrest module is adapted to branch User is supportted, wherein the headrest assemblies are operatively coupled to the backrest module.

23. a kind of headrest assemblies for being adapted to be coupled to seat arrangement, including：

Support meanss, the support meanss are configured to may be pivotably coupled to the backrest module of seat arrangement, with around the first pivot Line moves pivotally；

Rest the head on part, the headrest part may be pivotably coupled to the support meanss, with around the separated with first pivotal line Two pivotal lines move pivotally, wherein allow it is described headrest part around second pivotal line pivot independently of the support meanss around The pivot of first pivotal line；And

Coupling device, the coupling device is configured to make the headrest part be operatively coupled to the support meanss so that permit Perhaps described headrest part is pivoted around with the pivot area that first pivotal line and second pivotal line are separated.

24. headrest assemblies according to claim 23, wherein the pivot area and the headrest part and the support meanss In at least one separate.

25. headrest assemblies according to claim 24, wherein the pivot area and the headrest part and the support meanss All separate.

26. the headrest assemblies described in any one in claim 23-25, wherein when vertical relative to the back rest When ground adjusts the headrest part, the distance between first pivotal line and second pivotal line are held substantially constant.

27. the headrest assemblies described in any one in claim 23-26, wherein the support meanss are rubbed comprising first Articulated mounting is wiped, the first friction articulated mounting is configured to make the support meanss may be pivotably coupled to the backrest group Part.

28. headrest assemblies according to claim 27, wherein the headrest part is pivotable using the second friction articulated mounting It is coupled to the support meanss in ground.

29. the headrest assemblies described in any one in claim 23-28, wherein the headrest part includes arcuation track Portion, the arcuation orbit portion is slidably engaged by the support meanss so that relative to described in the orbit portion slidable adjustment Support meanss make the headrest portion be pivoted around the pivot area.

30. the headrest assemblies described in any one in claim 23-28, wherein the support meanss are inclined comprising spring The fastener of pressure, the fastener of the spring bias engages the headrest assemblies using frictional force so that the headrest assemblies structure Cause to be selectively adjusted relative to the backrest module between multiple upright positions.

31. headrest assemblies according to claim 30, wherein the headrest part includes multiple lock pins, the multiple lock pin is mutual The fastener that is spaced and can be biased by the spring is selectively engaged so that the headrest part be held in it is described vertical At position.

32. headrest assemblies according to claim 31, wherein the multiple lock pin is a pair of multiple lock pins, it is the pair of Multiple lock pins include more than first lock pin and more than second lock pin, the lock pin in more than first lock pin is by described the In more than two lock pin the lock pin skew so that when vertically adjusting the headrest, the fastener alternately with it is described More than first lock pin and more than second lock pin engagement.

33. the seat arrangement of the headrest assemblies described in any one in a kind of 23-32 including claim, and also include：

Portions component, the portions component is adapted to support user；And

Backrest module, the backrest module is operatively coupled to the portions component, and the backrest module is adapted to branch User is supportted, wherein the support meanss of the headrest assemblies may be pivotably coupled to the backrest module.