CA2503559A1 - Seat suspension - Google Patents

Abstract

A seat suspension has a base (12) with a foundation extending upwardly at a forward portion. A pair of panels (22, 24) is hingedly mounted to the foundation with a spring (36, 38) between each panel and the base. The panels are hinged to the foundation by a living hinge (16).

Description

SEAT SUSPENSION
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Application Serial No. 60/319,657, filed October 29, 2002.
BACKGROUND OF THE INVENTION
Field of the Invention The invention relates to seats and particularly to seats with suspensions or other apparatus for absorbing shock. The invention also relates to seats that are convertible for use in different positions.
Description of the Related Art There are many styles and configurations of seating, largely driven by the applications for which the seating is to be used. Seat suspensions are often provided to enhance comfort and health. In stationary seating, suspension is most often provided by springs, slings, and/or cushioning. Where seating is used in mobile applications such as motor vehicles, boats, aircraft, and wheelchairs, shock absorption is an additional criterion for seat design. Typically, the seating will consist of a sling as in a wheelchair, or a frame structure that is overlaid or covered with foam padding that is then encased within a cover as in a motor vehicle seat. Suspension is frequently provided by parallelogram or X linkages in conjunction with compression springs, leaf springs, or pneumatic springs.
In some applications, such as in high-performance boating, shock absorption becomes critical. A typical seat design is a pedestal-style seat supported on a pedestal above a surface such as the deck. During operation of the boat, the seated user absorbs the shock transmitted from the boat surface through the pedestal and into the seat. These shock forces are intensified when the associated boat is operated in rough or turbulent waters, or when the hull of the boat strikes large swells and wakes.
There is a need for an improved seat suspension, to provide comfort for users in either stationary or mobile applications, and, in the latter, also sufficient to absorb shocks that would otherwise be transmitted to the seated user. Moreover, any such seat suspension should be economical to manufacture.

SUMMARY OF THE INVENTION
A seat according to the invention has a platform with a foundation at a forward edge thereof. A pair of panels is hingedly mounted to the foundation and the free end of each panel is sprung over the platform. In one embodiment, the panels are hinged to the foundation by a living hinge. In another embodiment, the panels are formed of glass springs, wherein each panel comprises one arm of the spring. In one aspect, the panels are spring by a compression spring. In another the panels are sprung by a torsion spring.
The seat can be covered with a cushion and a cover in conventional manner.
Also, the platform and foundation can form a base support and the back can be hinged to the base support. In one embodiment, the base support folds up, much like a theater seat, and is biased to the closed position. The underside of the platform is configured to provide lumbar support when a user stands adjacent to it.
DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective partially exploded view of a seat frame with suspension according to the invention.
Fig. 2 is a perspective view of a seat incorporating a seat suspension according to the present invention, with a cover and padding partially cut away.
Fig. 3 is a cross sectional view of the seat suspension of Fig. 1 according to the invention.
Fig. 4 is a cross sectional view of a second embodiment of a seat suspension according to the invention.
Fig. 5 is a cross sectional view of a third embodiment of a seat suspension according to the invention.
Fig. 6 is a perspective view of another embodiment of a seat with a seat suspension according to the invention.
Fig. 7 is an exploded view of a further embodiment of a seat with a seat suspension according to the invention.
Fig. 8 is a perspective view of another embodiment of a seat according to the invention in the open position.
Fig. 9 is a perspective view of the embodiment of the seat of Fig. 8 in the closed position.

Fig. 10 is a perspective view of an embodiment of a seat suspension according to the invention accommodated for the seat of Figs 8 and 9.
Fig. 11 is a perspective view of the underside of the seat suspension of Fig.
10.
Fig. 12 is a perspective view of a wheelchair incorporating a seat suspension according to the invention.
Fig. 13 is a perspective view with parts exploded of a further embodiment of an adjustable seat suspension according to the invention.
Fig. 14 is perspective view of an alternative adjustable seat suspension according to the invention.
Fig. 15 is perspective view of another adjustable seat suspension according to the invention.
Fig. 16 is perspective view of another adjustable seat suspension according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Looking first at Fig. l, there is illustrated a seat frame 10 comprising a base 12 made of a rigid material such as wood, metal, a composite, or a polymer. The base 12 can be solid as illustrated or it can be a frame of some sort. At one edge of the base 12 is a foundation 14 that supports a hinge 16. In the embodiment of Fig. 1, the hinge 16 comprises a series of knuckles 18 and a pintle 20, where the hinge axis 17 is collinear with the longitudinal axis of the pintle 20. It will be understood that the foundation 14 is eventually disposed toward the front of the seat. Hinged to the foundation 14 are a first panel 22 and a second panel 24. Each panel 22, 24 has a free end 26, 28 respectively, extending away from the foundation 14. Knuckles 30 of the first panel 22 and knuckles 32 of the second panel 24 cooperate with the knuckles 18 on the foundation 14 in receiving the pintle 20 to form the hinge 16. The pintle 20 is retained in place by a cotter pin 21. The base 12 has a socket 34 beneath each free end 26, 28. A first compression spring 36 rests in the socket 34 beneath the free end 26 of the first panel 22 and a second compression spring 38 rests in the socket 34 beneath the free end 28 of the second panel 24. Thus, each panel 22, 24 is separately hinged and sprung. Where the foundation 14 will be at the front of a seat, it will be apparent that the first panel 22 will be toward the right hand side of the seat and the second panel 24 will be toward the left hand side of the seat. It will be further understood that any type of spring can be used, e.g., a coil spring, a leaf spring, a gas spring, or a pneumatic spring.
Referring now to Fig. 2, it can be seen how the suspension illustrated in Fig.

can be incorporated into a seat according to the invention. The seat 40 in Fig. 2 comprises a base 42 and a back 44. The base 42 is mounted to a pedestal 45 that provides a seating height to the seat 40. The back 44 extends upwardly relative to the base 42 in any conventional manner. For example, the back 44 may be mounted directly to the base 42, or it may be secured to another element to which the base 42 is also mounted. The manner of connection between the base 42 and the back 44 is not relevant to this invention. The base 42 comprises a foundation 48 at a forward edge thereof. Right and left panels 50, 52 are hinged to the foundation 48 and sprung from the platform 46 as illustrated, for example, in Fig. 1. Cushions 54 and 55 cover the base 42 and the back 44, respectively. Preferably, the cushions 54, 55 are shaped to support the seat and back of a user. The cushions may be connected to each other or may form a single unit, so long as they are adapted to accommodate any relative motion between the seat and the back. Covers 56 and 57 cover the cushions 54 and 55, respectively, for protection, aesthetics, and durability. It will be apparent that with the suspension according to he invention, a user can sit on the base support 42 and gravitational forces on the body will be absorbed both by the cushion 54 and the sprung panels 50, 52. Moreover, as the user leans from side to side, more force will be directed to the panel on that side. Say for example, a user sitting on the seat 40 leans to the user's right. This may occur if the user physically leans, or alternatively if the seat moves, such as if it were in a motor vehicle that hits a bump or a wake. In this instance, the panel 50 absorbs more force than the panel 52, causing the panel 50 to deflect downwardly against the spring bias, and causing the panel 52 to be relieved somewhat.
There are many ways of effecting the hinged panels according to the invention. Fig. 3 illustrates in cross-section the configuration illustrated in Figs. 1 and 2. The base 12, 46 supports a foundation 14, 48 at one end thereof and a back 44 at the other end thereof. The panel 22, 50 is hinged to the foundation 14, 48 by the hinge 16 and sprung from the platform 12, 46 by the compression spring 36.
Another embodiment is illustrated in Fig. 4 where like numerals will reference like components in earlier drawings. Here the panel 22 is hinged to the foundation 14, and the base 12 has a back 44 extending upwardly therefrom. But the shape of the base is different in that it accommodates a torsion spring 58 between the panel 22 and the platform 12. The hinge 59 can be a pin hinge similar to that of Figs. 1-3, or it can be a living hinge as shown here. The latter is amenable to molding the seat, by a process such as blow molding or injection molding.
Fig. 5 shows another embodiment of a seat suspension according to the invention. Here the platform, foundation and seat back are integrally molded.
Preferably, the base and foundation will be integrally molded to form a base assembly 60, and the back 62 will be separately molded for connection to the base assembly.
Blow molded or spin molded construction has the advantages of providing structural rigidity and durability with light weight at low cost. Any method of providing hollow molding can be utilized. A glass spring 64 has a bight portion 66 and two aims 68, 70. The bight portion 66 is held against the foundation 72 of the base assembly 60.
As illustrated, the bight portion 66 nests within a complementary shaped recess 74 in the foundation 72. Of course, attachment of the bight portion 66 to the foundation 72 can be by any reasonable means. One arm 68 extends into free space above a well 76 in the base assembly 60, and the other arm 70 rests in the well. The arm 68 serves as a seat panel and the resilience of the glass spring material provides suspension for the seat. In accord with the invention, at least two seat panels are provided side by side.
It will be understood that in any of the embodiments illustrated in Figs 3-5, there may be a cushion and covering overlying the seats. Cushioning and covering is not necessary, however, as shown in the embodiment of Fig. 6. A seat 80 comprises a base 82 and a back 84 hingedly mounted to the base 82 by a hinge 86. The back will thus fold forward against the base 82. The base support 82 is preferably a blow molded plastic comprising a molded foundation 88 at a front portion thereof and a recessed well 90. Glass spring panels 92, 94 are secured to the foundation 88 or to the bottom of the well 90, in a manner similar to that illustrated in Fig. 5. The back 84 is also a hollow molded plastic, comprising a well 96 disposed where the normal lumbar region of a user's back will be when the user is seated. Another glass spring 98 is disposed in the well 96, and secured to the back 84 in a manner similar to the attachment of the glass spring panels 92, 94 to the base support 82. The glass spring 98 has an arm 100 that is curved and projects slightly above the surrounding surface of the back 84 to provide flexible lumbar support.
If drain holes are provided in the well 90, the seat is adapted for use in any outdoor environment. Possible uses include stadium seats, marine seats, and lawn chairs. Of course one or more surfaces could be covered with upholstery, which upholstery can be designed to be weather resistant. The seat can also be covered with cushions and covering as in earlier embodiments.
A further embodiment of a seat according to the invention is shown in Fig. 7.
Here, a blow molded base support 102 has a well 104 molded into it. At the bottom of the well 104 is a series of stiffening ribs 106. As illustrated, the ribs 106 run from a front of the base support 102 to a back of the base support, but they can be disposed in any orientation to provide stiffening as needed. At the front of the base support 102 is a strengthened foundation 108 with a series of molded knuckles 110 protruding rearwardly into the we11104. A right hand panel 112 is also formed of a hollow molded polymer and has a series of knuckles 114 protruding from a front thereof.
Likewise, a left hand panel 116 is formed of a hollow molded polymer and has a series of knuckles 118 protruding from a front thereof. All of the knuckles 110, 114, and 118 have apertures therein, disposed to be in registry when the respective knuckles overlap. A pintle 120 extends through an aperture 122 ire the base support 102 and through the knuckle apertures to establish a hinge for the right and left hand panels 112, 116. The pintle 120 is retained in place by a cotter pin 121.
Preferably, the upper surface of each panel 112, 116 is shaped to accommodate the buttocks and more particularly, the ischial tuberosity of the pelvis in the seated position. One of a pair of compression springs 119 is disposed beneath the free end of each panel 112, 116 and is seated in a molded socket 120 in one of the ribs 106.
A hollow molded back 122 is shaped to conform to the back of a user, and incorporates a lumbar support 124. Here, the lumbar support 124 can be a glass spring as shown in Fig. 6 or it can be an air bladder or some other flexible material such as a mesh. Preferably, the back 122 is hinged to the base support 102 in a conventional manner.
Any one of the previous embodiments of a seat suspension according to the invention can be adapted for the embodiment shown in Figs. 8 and 9. Here a base support 130 is hingedly mounted to a frame 132 by, for example, pins 134. A
back 136 would typically also be mounted to the frame 132 in conventional manner.
It will thus be apparent that the base support 130 is pivotable relative to the fixed back 136 between an open position as shown in Fig. 8 and a closed position as shown in Fig. 9.
Ideally, the base support 130 is biased toward the closed position, much like a theater seat. Such bias can be accomplished by torsion springs adjacent the pins 134, or simply by providing weight at a rear of the base support 130 so that there is more weight behind the pins 134 than in front of the pins, thereby unbalancing the base support, with bias toward the rear. This structure is particularly useful in a high performance watercraft where a seated user frequently has to stand at the seat under certain conditions. Here the user can do so simply by standing, whereupon the base support pivots toward the closed position.
Figs. 10 and 11 show an alternative embodiment of the seat, enhancing the benefits of the seating embodiment shown in Figs. 8 and 9. In Fig. 10, the base support 130 includes a plate 138 at the pins 134, against which a torsion spring in the frame can act. The interior of the base support 130 with a well, etc. is as described earlier. Tmportantly, however, the underside of the base support is shaped with a bulge 140 toward the front of the base support. The bulge is shaped to accommodate the lower back of a user so that when the base support is in the closed position as in Fig. 11, the bulge 140 will be disposed to provide lumbar support for the lower back of a user standing against the back support.
. Fig. 12 shows the use of a seat suspension according to the invention in a wheelchair. Of course, a base support with hinged panels according to the invention as described above in Figs.. 5 and 6, for example, can be placed on the sling seat of a wheelchair to provide the benefits of the inventive seat suspension to a wheelchair .
user. in Fig. 12, a seat suspension 150 according to the invention is incorporated into the wheelchair design. Here, a base support 152 similar to the embodiment shown in Fig. 6 has a living hinge 154 in the support between adjacent portions, enabling the base support to fold laterally. Each outside edge of the base support is likewise connected to the wheelchair by hinges 156. The panels 22, 24 are separate, each panel being associated with a particular base support panel.
Figs. 13-15 illustrate embodiments where the suspension force is adjustable.
The suspension force is the force needed to deflect a panel from a rest position.
Looking now at Fig. 13, a seat suspension 200 according to the invention is similar in overall configuration to the embodiment of Fig. 1, and, thus, similar components bear like numerals. Instead of single spring seats, however, a plurality of spring seats 202 are disposed in the base 12 along a line beneath each panel 22, 24 perpendicular to the axis 17 of the hinge 16. It can be seen that the spring 36 can be placed in any of several possible positions in the plurality of seats. As the spring 36 is positioned closer to the hinge axis 17, the suspension force will increase. The further away the spring 36 is from the hinge axis 17, the less the suspension force.
Fig. 14 shows an alternate embodiment of an adjustable seat suspension 208 according to the invention. Here, a spring seat retainer 210 is slidably mounted to the base 12. The spring seat retainer has two spring seats 212, each positioned beneath a respective panel 22, 24. Means are provided to fix the spring seat retainer 210 to the base 12 at a given position. Such means can include a spring retainer, a ratchet and pawl mechanism, or other locking device. To adjust the suspension force, the spring seat retainer 210 can be moved to a predetermined location on the base 12, either closer to or further away from the hinge axis 17. Indicia 214 can be provided on the base 12 or elsewhere to identify predetermined positions. Adjustability can also be provided by threaded rods 216 in the base 12 that are journaled into the spring seat retainer 210 and disposed normal to the hinge axis 17. Rotating the threaded rods 216 will urge the spring seat retainer 210 along the rods either toward or away from the hinge axis 17.
Fig. l 5 illustrates another embodiment of an adjustable seat suspension 220 with pneumatic springs 222. Here, eacin pneumatic spring 222 comprises an air bag 224 disposed between an upper mounting plate 226 and a lower piston 228. The piston 228 will typically have connections (not shown) for fluidly connecting to a source of pressurized air. Suspension force can be adjusted by altering the air pressure within the air springs 222. Alternatively, or in addition, the piston 228 of each air spring 222 can be mounted to the base 12 by a bolt through an elongated slot 230 extending normal to the hinge axis 17. To adjust the suspension force, the piston 228 can be moved along the slot 230 to a predetermined location on the base 12, either closer to or further away from the hinge axis 17.
Fig. 16 shows another embodiment of an adjustable seat suspension 250 in accord with the invention. Here, the seat suspension has an adjustment mechanism 252 that adjusts the vertical position of the springs 36 rather than the suspension force. It is useful where travel of the panels ,22, 24 is limited. The base 12 has a pair of holes 254, each hole being located beneath a respective panel 22, 24. An adjuster flange nut 256 having a flange 258 larger in diameter than the holes 254 and a threaded portion 260 smaller in diameter than the hole 254 is disposed in the hole with the flange 258 bearing against the base 12. The threaded portion 260 projects through the hole 254. The adjuster flange 256 is secured in place by a jam nut 262.

The adjuster flange is hollow with an internal diameter larger than the diameter of the spring 36, and it has an axial slot 264 in the threaded portion 260. An adjuster washer 266 having a cross piece 268 smaller than the slot 264 is loosely fitted over the threaded portion 260 with the cross piece 268 received in the slot 264 so that the adjuster flange is free to move axially relative the longitudinal axis of the adjuster flange nut 256. An adjuster nut 270 is threaded on the threaded portion 260 to hold the adjuster washer 266 at a given position. The spring 36 is placed within the adjuster flange nut until it rests on the cross piece 268. The vertical position of the spring 36 can then be adjusted by turning the adjuster nut 270.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.

Claims (14)

What is claimed is:

1. A seat suspension ( 10, 150, 208, 220, 250) comprising a base ( 12, 46, 60, 82, 102, 130, 152) having a front portion and a rear portion, a foundation (14, 48, 72, 88, 108) extending upwardly from the base at the front portion, a pair of panels (22 and 24, 50 and 52, 92 and 94, 112 and 116) each having a forward end and a rearward end, the forward end of each panel extending rearwardly from the foundation at a hinge (16, 59, 66, having a hinge axis (17) with the panels side by side, wherein each panel is pivotable about the hinge axis and the rearward end of each panel is biased away from the base.

2. A seat suspension according to claim 1 further comprising a spring (36, 58, 64, 119, 222) between the base and each panel.

3. A seat suspension according to claim 2 wherein the force of the spring is adjustable.

4. A seat suspension according to claims 2 or 3 wherein the position of the spring is adjustable along a line normal to the hinge axis.

5. A seat suspension according to claims 1 - 4 wherein the hinge is a living hinge (59).

6. A seat according to claim 1 wherein the panels are formed of glass springs (64), wherein each panel comprises one arm (68) of the spring.

7. A seat suspension according to claims 2 - 5 wherein the spring is a pneumatic spring (222).

8. A seat suspension according to claims 1-7 wherein the base is molded.

9. A seat suspension according to claim 8 wherein the foundation is molded.

10. A seat suspension according to claim 9 wherein the base and foundation are integral.

11. A seat comprising a seat suspension according to any of claims 1 - 10.

12. A wheelchair comprising a seat suspension according to any of claims 1-10.

13. A marine seat comprising a base support (130) hingedly mounted to a frame (132) for movement between an open position where the seat is generally horizontal so it can be sat upon, and a closed position where the seat is generally vertical, wherein the seat is biased toward the closed position, and wherein the frame is tall enough so that a user can stand with his or her back to the seat in the closed position and lean against it, and wherein the seat has an underside with a bulge (140) to accommodate the lower back of a person leaning against the seat in the closed position.

14. A marine seat according to claim 13 incorporating a seat suspension according to any of claims 1 - 10.