AU691176B2

AU691176B2 - A chair

Info

Publication number: AU691176B2
Application number: AU65835/94A
Authority: AU
Inventors: David John Chapman; Madonna Mary Harris; Paul Clive Ian Jeffrey; Hazel Menehira
Original assignee: Lyfta Chair Co Ltd
Current assignee: Lyfta Chair Co Ltd
Priority date: 1993-04-06
Filing date: 1994-04-06
Publication date: 1998-05-14
Anticipated expiration: 2014-04-06
Also published as: AU6583594A; WO1994022410A1

Description

~cq~n~ 1DaPParn 811~llllsllslasl WO 94/22410 PCT/NZ94/100026 1 TITLE: A CHAIR

INTRODUCTION

This invention relates to a chair and more particularly, to a chair for a person, for example a person having limited mobility.

BACKGROUND TO THE INVENTION In the past, often individuals suffering from injury or ailment have great difficulty in achieving or maintaining self sufficiency, particularly as it relates to their habitational mobility.

Whilst the invention relates to a chair for persons having limited mobility, the invention is not limited to such an arrangement and the invention has applicability across the full spectrum of uses.

A particular problem faced by people with limited mobility is to be able to move about yet also to rest.

Often, it is possible for such persons to move relatively iLdependently, whilst standing or alternatively, to rest adequately when seated; however, often such people require assistance to move between a standing and a rest position, or vice versa in view of the strain which that transition places upon portions of the body, particularly in joints.

SUBSTITUTE SHEET -P l IWO 94/224110 PCT/NZ94 '0026 2 In the past, attempts have been made to ameliorate the difficulties which persons having limited mobility face, however, in the main these have been relatively complicated in construction, are therefore expensive and have often required substantial and regular maintenance beyond the scope of the user or his or her family.

Frustrationally, most prior art arrangements have provided little if any improvements for the person in transitting between the standing and seating provision.

Prior arrangements have also been relatively bulky and the opportunity of the use has, as a result, been limited, particularly in the home.

For fortunate individuals with unlimited mobility, there is also a need for a support which provides user convenience and comfort in transitting between a standing and a sitting position both for domestic and commercial usages; for example in the home, in medical and surgical rooms (for example for use by patients of doctors, dentists, opticians, etc.) and in transportation means.

It is an object of this invention to come some way in overcoming the abovementioned problems or at least provide the public with a useful choice.

SUBSTITUTE SHEET BRIEF DESCRIPTION OF THE INVENTION According to one aspect of this invention there is provided a chair for a person including a frame, a seat portion pivotally mounted to rotate between a first or seated position and a second or upright position in which the upper surface of said seat is presented towards the front of said chair in said second position; and at least one leg portion provided adjacent a front edge of said seat portion and pivotally mounted thereto and wherein said leg portion depends substantially downwardly from said seat portion in said first position and said leg portion and seat portion both have their supporting surfaces facing a front of said chair in said second position, and wherein a foot rest is provided adjacent an edge of said leg portion distal from said front edge of said seat portion, the arrangement being such that weight supplied to said foot rest by a person sitting in the chair enables the rotation of said upper surface of said seat portion from said first position to said second position.

*0 0 oo to co• o o•: eo 4 BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to the accompanying drawings in which: Figure 1: is a side view of one embodiment of the invention in the form of a chair in the seated rest position.

i:: 0 0 :.i"2 .o i o WO 94/22410 PCTNZ94/00026 Figure 2 is a cross-section of the apparatus of Figure 1 substantially along a fore and aft centre line of the seated portion thereof.

Figure 3 is side view of the chair of Figure 1 in a substantially upright position.

Figure 4 is a cross-section of the chair of Figure 3 according to the cross-section described in respect of Figure 2.

Figure 5 is a front view of the support in the upright condition as shown in Figure 3.

Figure 6 is a rear view of the support in an upright position as shown by Figure 3.

Figures 7 to 15 show sequentially the operation of the chair sequentially operating the chair from the upright position as shown in Figure 7 to a seated position as shown by Figure 10 and then returning to a standing position at Figure Figure 16 is a rear view of the support in a substantially upright condition showing an alternative assembly of linkage to that of the apparatus of Figures 1 and 3.

Figure 17 is a perspective view of a further embodiment of the invention approaching a seated position.

Figure 18 is a perspective view of the embodiment of Figure 17 approaching an upright condition.

SUBSTITUTE SHEET WO 94/22410 PCT/NZ94/00026 6 DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The invention described is a chair suitable for use by a person having limited mobility and in the home to enable that person to live relatively independently and be able to move from an active standing position to a seated rest position and vice versa without the need for additional assistance or physical strain.

Whilst the invention is described with reference to such an arrangement, it is to be understood that the apparatus of the invention is also applicable in respect of a chair for persons of unlimited mobility for normal usage but providing an unusual degree of comfort for a user in transitting between a standing position and a seated position.

In the preferred form of the invention, the invention is provided as a single chair and is preferably formed from suitable available materials. In the main, the chair is provided with a frame formed in durable formable materials such as mild steel tube of round or square cross-section, together with suitable padding support portions according to known seat construction techniques.

SUBSTITUTE SHEET WO 94/22410 PCT/NZ94/00026 7 The invention is not limited to these techniques and as alternative materials become available, such materials can be incorporated in the invention.

Referring now to the drawings, and in particular Figures 1 to 6 and Figure 16, the chair is generally indicated by arrow 1.

The chair 1 in this preferred form of the invention includes a frame generally indicated by arrow 2 which in the preferred form of the invention is formed in mild steel rolled hollow section. The frame 2 incorporates a pair of spaced apart upstands 3 each having a foot portion 4 positioned across the base thereof to provide a means for supporting the frame 2 on a supporting surface. Upper portions 3a of the upstand 3 are in the preferred form of the invention provided with elongate arm rest 3b extending substantially horizontally fore and aft according to the chair and preferably extending relatively forwardly in relation to the chair so as to provide means for a person to grip the chair frame in use.

The chair in this preferred form of the invention provides a continuous support portion as generally indicated by arrow 10 for the user. The support portion generally defines a seat portion 11, a back portion SUBSTITUTE SHEET WO 94/22410 PCTNZ94/00026 8 12 and a leg portion 13 and is positioned between the upstands 3.

Each of the seat portion 11, back portion 12 and leg portion 13 are provided with a framework portion 14 preferably formed in suitable durable material, for example rolled hollow section mild steel and each portion is provided with a suitable bracketing means to support a section of the padding 10 there adjacent so as to define the substantially continuous padded portion 16 to provide the seat portion 11, back portion 12 and leg portion 13 in a disposition able to support a person when seated thereon.

In the assembly of Figure 16, preferably each of the seat portion 11, back portion 12 and leg portion 13 are preferably provided in substantially concave shells of laminated timber to thus provide substantially outwardly "concave" portions for accommodating padding for the relevant sections of the apparatus, and to provide strong and durable, yet relatively light-weight portions for the apparatus which are conveniently fabricated according to mass production techniques.

It will furthermore be appreciated that in the arrangement as shown with reference to Figure 16, the substantially outwardly concave shape of the seat SUBSTITUTE SHEET WO 94122410 PCTINZ94/00026 9 portion 11, back portion 12 and leg portion 13 provide a convenient means for hingeably engaging the portions one relative to the other in parallel planes extending outwardly from the front of the support and furthermore, in relation to the seat portion 11, conveniently enables mounting of the seat portion 11 with its pivotal connection tothe upstand 3. Suitable reinforcing means may be mounted between the respective inter-engaged pivots of the seat portion 11, back portion 12 and leg portion 13 so as to reinforce the laminated timber "shells", however, this is in no way essential to the invention.

With reference to the drawings, it will be appreciated that as the seat portion 11 tips, the back portion 12 and leg portion 13 also alter in their angle.

The frame portion 14 forming portions of the feet portion 11, back portion 12 and leg portion 13 are preferably pivotally and interconnected to either side of the chair on either side of a pivot connection 17 of the seat portion 11 relative to the upstands 3.

The pivotal connections 18 and 19 of the back portion 12 and leg portion 13 respectively, are each additionally controlled as is the angular disposition of the seat portion 11 relative to the back portion 12 and SUBSTITUTE SHEET

I-

WO 94/22410 PCT/NZ94/00026 10 leg portion 13, via linkage means 21 positioned between the leg portion 13 and the upstand 3 and a bracket portion 20 provided to extend below a level of the back portion 12 frame portion.

Whilst in the form of the invention in Figures 1 and 3 show the linkages 21 positioned to one side of the back portion 12, leg potion 13 and seat portion 11, in an alternative assembly of the invention, as shown in Figure 16, the linkages 21 are provided substantially medially of said seat portion 11, back portion 12 and leg portion 13, on a side of said seat portion, substantially opposite to the intended contact portion for the user. In this manner, it will be appreciated that the linkages can be substantially concealed within the seat frame assembly to enhance the ability for compact construction of the apparatus and to keep the linkage assemblies out of the way of prying fingers and the like, where they may be able to be caught and/or injured during operation.

It will be appreciated that as the seat portion 11 tips, the back portion 12 and leg portion 13 also alter in their angle owing to the positioning of their pivotal connections 18 and 19, the pivot 17 and the interconnection geometry of the linkages substantially SUBSTITUTE

SHEET

WO 94/22410 PCT/NZ94/00026 11 in the form of a non-parallel "parallel" linkage arrangement relative to the Figure 2 connection points.

Whilst in the preferred form of the invention, the padded arrangement for the seat portion 11, back portion 12 and leg portion 13 is substantially continuous, it is to be appreciated that an alternative form of the invention, the portions can be arranged to be substantially separate padded portions without departing from the scope or spirit qf the invention. The continuous padding arrangement is shown with reference to Figure 2 arnd in addition, it will be seen that in the preferred form of the invention, the leg portion 13 is provided with a footrest 22 thereon. In this form of the invention, the footrest 22 is provided for supporting the feet when in a seated condition and also for facilitating transition of the chair from the seated position to the upright position and vice versa.

Whilst the invention has been described with reference to Figures 1 and 2, and in a seated position, reference is now made to Figures 3 to 6 and Figure 16 which show the chair in a substantially "upright" condition, that is, in a position whereby the seat, leg and back support portions 11, 12 and 13, are substantially forward facing.

SUBSTITUTE

SHEET

WO 94/22410 PCT/NZ94/00026 12 ItL will be appreciated that in this condition, the chair is in a substantially compact rest state and ready to accept a person thereon. In this form of the invention, it will be seen that the seat portion 11 is tilted forwardly and is facing toward the front of the chair and the leg supporting portion 13 depends downwdrdly therebelow, with the footrest portion 22 adjacent a floor level. The back support portion 12 is also positioned in a substantially forward position relative to the chair as a whole and the grip or arm rest portions 3b extend forwardly of the padded portion.

With reference to Figure 3, it will be seen that the padded assembly provides a somewhat upright inclined "wall" against which a user may "back".

Figures 6 and 7 show the apparatus also in the upright condition as shown by Figures 3 and 4.

Now referring to Figures 8 to 16, it will be seen that a person wishing to utilise the chair substantially backs into the chair and stands on the footrest 22 and places the buttocks against the seat supporting portion 11. The person then leans substantially rearwardly against the substantially upright padded form which, it will be seen by Figure 9, tends to cause the seat portion to tilt upon its pivotal axis 17 causing SUBSTITUTE SHEET 'WO 94/22410 PCT/NZ94/00026 13 increased angularity between the seat port- 11 and adjacent back supporting portions 12 and leg supporting portion 13, controlled by the pivotal action of the seat and the interconnection of linkages 20 and 21 via the upstand 3.

It will be seen that as the seat portion 11 starts to tilt toward the horizontal plane, tipping away from a forwardly facing position, the seat portion 11 tends to support the buttocks, therefore supporting body weight as the upper portion of the body moves rearwardly and becomes increasingly supported by the back supporting portion 12 with the legs supported by the leg supporting portion 13 and footrest 22.

It will be appreciated that as the centre of gravity of the body weight placed on the seat portion 11, positions over the pivot point 17 of the seat portion 11, the chair reaches a state of substantial equilibrium, as is shown by Figure In Figure 10, it will be seen that the seat portion 11 is substantially horizontal and is supporting a majority of the weight of the user with the centre of gravity of the seat positioned substantially over or in line with pivot 17 of the seat portion 11. A relatively stable position is therefore reached where the legs and SUBSTITUTE

SHEET

WO 94/22410 PCTINZ94/00026 14 back of the user are supported in a comfortable condition.

Should the user wish to alight from the chair, the user merely shifts his or her centre of gravity forwardly as is seen commencing Figure 11 to cause the seat portion 11 to tilt from the horizontal, particularly as is shown by Figures 13 to 15, whereupon the seat portion 11 tilts forwardly increasingly placing the centre of gravity of the person forwardly of the pivot 17 thus causing the seat portion 11, back portion 12 and leg portion 13 to return progressively toward the upright position, tilting and moving the buttocks forwardly to assist the person to reassume a standing position.

It will be appreciated that this invention therefore provides a convenient means of assisting a person transitting between a standing and a seated position and vice versa utilising the balance of their body weight in relation to a pivoting or tilting action of the seat portion and corresponding movement of back and leg portions.

In further embodiments of the invention, it is envisaged that the linkage means 20 and 21 may be substantially adjustable or variable in length to alter SUBSTITUTE SHEET .WO 94/22410 PCTNZ94/00026 15 or vary the angular relationship between the seat portion, back portion and/or leg portion in either or both in the upright, seated rest position or in between, depending on requirements of use.

A yet further preferred embodiment of the invention is shown in Figures 17 and 18. Although the chair 50 in these figures is of similar operation and function to those described previously, the construction is somewhat different.

The chair 50 as shown in Figure 17 is approaching the seated position although further rotation of the major portions being the back portion 51, seat portion 52 and leg portion 53 is required to achieve a stable seated position. In the stable seated position, the base of the seat portion 52 will approach the horizontal.

It can be seen that in this embodiment, a frame 54 is provided having leg portions on to which wheels 56 are fitted for convenience. This particular apparatus is provided with the wheels 56 and a handle 57 so that the chair can be easily rolled across the floor, although, this chair could just as easily be provided without the wheels 56 or with larger rear wheels more in keeping with a conventional wheelchair.

SUBSTITUTE SHEET WO 94/22410 PCT/NZ94/00026 16 The frame 54 is connected to a support member 58 by a pivot 59 connected to the upstand of the frame 61 supporting the arm rest 62. This pivot 59 provides the centre of rotation of the seat portion 52.

Also, the support arm 58 runs along opposed edges of the seat portion 52 and nrovides support to pivotal connections 63 and 64 to the back and leg portions 51 and 53 respectively.

In this manner, any rotation of the support portion 52 about the pivot 59 is accompanied by a rotation of the connection points 63 and 64 on to the back and leg portions 51 and 53.

With the rotation joint being provided through joint 63 and 64 on to the back and leg portions 51 and 53 respectively, a further support to these portions is required. As can be seen best in figure 18, this additional support is provided. by link members 66 and 67 to the back portion 51 and leg portion 53 respectively.

In this preferred embodiment, the link portions 66 and 67 comprise substantially rigid link members mounted by a hinge connection 68 to the frame 54 and by a further hinge 69 to the back or leg portion 51 or 53.

SUBSTITUTE SHEET IWO 94/22410 PCT/NZ94/00026 17 It can be seen that in this embodiment, the link member 66 and 67 are provided as separate members to the back and leg portions respectively. They are mounted to different support members being support members 71 and 72 forming part of the overall frame 54. It should be noted that the link member 66 and 67 "-rovides support to the back and leg portions respectively, not only when in the stable seated and upright positions but also ensuring a smooth travel of these portions through the transition from one stable position to the other.

In preference, the pivot 59 should be positioned so that the weight of the apparatus without a user in the chair or with a user in the normal seated position is slightly biased to the stable seated position. It will then require movement of the user towards an upright position and the consequential shift in the centre of load on the chair to cause the portions 51, 52 and 53 to rotate towards the upright position and assist the user out of the chair.

A locking mechanism comprising a catch 73 and operating handle 74 is provided so that a cooperative catch on the seat portion 52 may be engaged by the catch 73 to lock the seat in place when desired. This will inhibit unwanted rotation of the support portions 51, 52 SUBSTITUTE SHEET .WO 94/22410 PCT/NZ94/00026 18 and 53 until the user wishes to attain an upright position and operates the lever 74 to release the catch.

In addition to the purely pivotal arrangement shown in all the preferred embodiments, it is also possible to provide such a chair with hydraulic, pneumatic or any other form of operation such that the support portions being the seat portion 52 and the back portion 51 and/or leg portion 53 rotate from a seated configuration to a substantially upright configuration.

Further, whilst the invention has been described with reference to co-acting seat, leg and back portions, an alternative form of the invention is envisaged where either leg or back portions may be dispensed with or both leg and back portions may be dispensed with, depending on the requirements of use.

The back portion of the seat as described in the preferred embodiments could either be removed entirely or replaced by a fixed back portion available for use only in the seated position. The major portion of support to the user in the shifting to or from the seated position is supplied by the pivoting seat and the transfer of weight to or from the foot rest supplied on the leg portion. Therefore, although the back portion is preferred to provide extra stability when the user SUBSTITUTE SHEET WO 94/22410 PCTINZ94/00026 19 enters the chair in its upright condition, it is not essential to the invention.

In these preferred embodiments in which the seat is activated by a shifting of weight about the pivot, the leg portion 53 gains increased importance. It is this leg portion and in particular the foot rest supplied at the base of this portion which carries the weight as the user rises from the seated position and transfers that shift in weight to rotation of the seat about the pivot.

Similarly, when transferring from an upright to a seated position, the weight of the user is shifted from the foot rest supplied at the base o' the leg portion 53 to the seat portion 52.

Alternative activation of the seat by hydraulic, pneumatic or other forms of operation could allow the leg portion to be dispensed with due to the reduced need for the foot rest to carry the weight transfer.

Nevertheless, the leg portion and in particular the foot rest is still preferred so that it may support the user and lower the users feet to the ground or from the ground during operation.

The invention has also been described with reference to the provision of a substantially static chair frame. In an alternative form of the invention, SUBSTITUTE SHEET WO 94/22410 PCTNZ94/00026 20 the invention is applied to a mobile arrangement, being a wheelchair. Other forms could include an invalid's trolley or other assembly. Further, it is envisaged that the apparatus may be able to be incorporated into vehicle seats where conditions of use so require.

Thus, by this invention, there is provided a support for a person to enable a person to readily move between an upright and a seated position and from a seated position to an upright position, with reduced body strain.

SUBSTITUTE SHEET

Claims

1. A chair for a person including a frame, a seat portion pivotally mounted to rotate between a first or seated position and a second or upright position in which the upper surface of said seat portion is presented towards the front of said chair in said second position; and at least one leg portion provided adjacent a front edge of said seat portion and pivotally mounted thereto and wherein said leg portion depends substantially downwardly from said seat portion in said first position and said leg portion and seat portion both have their supporting surfaces facing a front of said chair in said second position, and wherein a foot rest is provided adjacent an edge of said leg portion distal from said front edge of said seat portion, the arrangement being such that weight supplied to said foot rest by a person sitting in the chair enables the rotation of said upper surface of said seat portion from said Jlrst position to said second position.

2. A chair as claimed in Claim 1 wherein a back portion is provided and pivotally mounted adjacent a back edge of said seat portion. e:

3. A chair as claimed in Claim 2 wherein said leg portion and said back portion have a linkage to control the positional relationship between the seat portion and the back portion and said leg portion. o: o

4. A chair as claimed in Claim 2 or Claim 3 wherein said seat portion is pivotally mounted to said frame substantially equidistant between said front and said rear edges of said seat portion. 9 9. A chair substantially as hereinbefore described with reference to any one of the embodiments of the invention of the accompanying drawings. DATED this 19th day of March, 1998 HAZEL MENEHIRA, MADONNA MARY HARRIS, PAUL CLIVE IAN JEFFREY AND DAVID JOHN CHAPMAN WATERMARK PATENT TRADEMARK ATTORNEYS 290 BURWOOD ROAD HAWTHORN VICTORIA 3122 AUSTRALIA CJH:BA:JC VAX DOC 018 AU6583594.WPC 6 e ee* *e e o0