NZ523169A - Improved wheelchair - Google Patents

Abstract

A chair (1) including a base frame (3); a seat part (11) and a back part (13) supported from the base frame, the seat part (11) and back part (13) being reclinable between a first seating position and a second reclined position; and a tablet (19) supported by the chair (1) and configured such that as the seat part (11) is reclined the tablet (19) moves with the seat part (11) and substantially maintains its angle relative to the base frame (3) and/or the ground.

Description

5231 69 INTELLECTUAL PROPERTY OFFICE OF N.Z MAR 200*1 RECEIVED NEW ZEALAND PATENTS ACT, 1953 No: 523169 Date: 16 March 2003 (post-dated from 16 December 2002) COMPLETE SPECIFICATION IMPROVED WHEELCHAIR I, GEOFFREY GRAHAM SHEARER, a New Zealand citizen of 24 Plymouth Street, Karori, Wellington, New Zealand, do hereby declare the invention for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: 2 IMPROVED WHEELCHAIR Field of the Invention This invention relates to the art of wheelchairs for transporting a person having limited 5 mobility. Whilst described with particular reference to a wheelchair, at least some of the features described herein will have application in other types of chairs, for example reclining armchairs or office task chairs.

Background Conventional chairs or wheelchairs have been known to include a tablet for supporting an item for access by a chair occupant. Known tablet systems for use with chairs are attached to a stationary part of the chair, such as part of the chair base frame. Whilst this is satisfactory for a fixed chair, if the chair is capable of reclining then the relative positions of the chair and tablet surface will change significantly as the chair is reclined. 15 The chair occupant would only be able to easily use the tablet whilst the chair is in an upright position, as he or she may not be able to comfortably reach the tablet after the chair has been reclined. It would be desirable to provide a chair having a tablet which is adapted to move with the seat part as the seat part is reclined (so there is no or little relative movement between the tablet and the seat part), and which can also maintain its 20 angle relative to the ground during the movement. That way, should an occupant have a drink sitting on the tablet while the chair is in an upright seating position, it will not tip over as the seat part is reclined. 137227-1 3 It is an object of at least a preferred embodiment of the present invention to provide a chair which has a tablet which is adapted to move with the seat part as the seat part is reclined (so there is no or little relative movement between the tablet and the seat part) and which can also maintain its angle relative to the ground during the movement, and/or 5 which at least provides the public with a useful choice.

Summary of the Invention In accordance with a first aspect of the present invention, there is provided a chair including: a base frame; a seat part and a back part supported from the base frame, the 10 seat part and back part being reclinable between a first seating position and a second reclined position; and a tablet supported by the chair and configured such that as the seat part is reclined the tablet moves with the seat part and substantially maintains its angle relative to the base frame and/or ground.

The chair may include a bucket seat with the seat part and back part being arranged at a predetermined angle, such that the seat part and back part are reclinable as a single unit. The bucket seat is preferably arranged so that as it moves from a seating to a reclined position, its pivot point moves forward and downward to maintain an occupant's centre of gravity substantially in the same position relative to the base frame.

The seat part and back part may be arranged to move independently.

Suitably, the seat part is supported by a seat support frame. 137227-1 4 The chair preferably includes a drive mechanism to selectively move the seat part between the seating position and the reclined position. The drive mechanism may include an electric actuator, one end of which is operatively connected to the base frame 5 and the other end of which is operatively connected to the seat part and/or seat support frame.

Preferably, a rear lever arm is pivotally connected at or adjacent a rear part of the base frame at a lower rear lever arm pivot and pivotally connected at or adjacent a rear part of the seat part or seat support frame at an upper rear lever arm pivot, such that the seat part is arranged to move about a radius defined by the rear lever arm. A tilt actuating arm may be pivotally connected to the base frame forward of the lower rear lever arm pivot and pivotally connected to the seat part or seat support frame forward of the upper rear lever arm pivot, such that the intersection of the seat part and back part moves forward in an arc around the lower rear lever arm pivot and the seat part tilts towards the reclined position as the seat is reclined. The rear lever arm, the base frame, the tilt actuating arm, and the seat part or seat support frame preferably form a four bar linkage. The chair may include a pair of rear lever arms, one on either side of the chair, and a pair of tilt actuating arms, one on either side of the chair; wherein the rear lever arms, tilt actuating arms, base frame, and seat part or seat support frame form two four bar linkages.

The chair preferably includes a linkage arrangement which operatively connects the tablet to the seat part. The tilt actuating arm may include a connecting part extending forward Intellectualhhuh li ilT !lN office OF N.Z 137227-1 12 may im received. of its pivot point with the seat part or seat support frame, actuating arm are suitably angularly oriented.

The two parts of the tilt The connecting part extending forward of the seat pivot is preferably pivotally connected 5 to a linkage member. The linkage member is advantageously pivotally connected to a tablet support arm for supporting the tablet. The tablet support arm may include a bush which is arranged for receipt of part of a tablet support.

The linkage member is suitably floating relative to the seat part and held between the 10 connecting part of the tilt actuating arm and the tablet support arm.

The chair preferably includes a tablet support which is configured to support the tablet from the linkage arrangement. The angle of the tablet relative to part of the tablet support and/or base frame is preferably selectively adjustable. In a preferred embodiment, a first 15 relatively short lever arm is pivotally connected to the tablet support and the tablet, and a second relatively long lever arm is pivotally connected to the tablet support and the tablet forward of the first relatively short lever arm, the lever arms configured such that the tablet can be moved from a position substantially parallel with part of the tablet support and/or base frame to a position wherein the part of the tablet toward the front of the chair 20 is raised relative to the part of the tablet toward the rear of the chair. Two first lever arms and two second lever arms may be pivotally connected to the tablet support and tablet. 137227-1 6 The angle between the tablet and part of the tablet support and/or base frame is advantageously adjustable by up to about 45 degrees.

The chair may include chair arms which are moveable with the seat part, and the linkage 5 arrangement is suitably provided in at least one of the arms such that as the seat part is reclined, the tablet moves with the seat part and substantially maintains its angle relative to the base frame and/or ground.

The tablet and/or tablet support are preferably removable from the chair.

The chair preferably includes a leg rest which is configured to move with the seat part as the seat part is reclined. The angle of the leg rest relative to the seat part is preferably selectively variable.

The chair is advantageously a wheelchair.

In a preferred embodiment, the base frame may be attached to a pair of enlarged rear wheels and a pair of smaller front wheels. The front wheels are suitably pivotable about vertical axes so that the wheelchair can be easily turned.

The wheelchair may be a manually powered wheelchair, or alternatively, and more preferably, may be drivable by its own motive force and may include an electric drive motor, for example. 137227-1 7 Brief Description of the Drawings Preferred embodiments of the present invention will be described by way of example only with reference to the accompanying figures in which: Figure 1 is a side elevation view of a first preferred embodiment wheelchair having a reclinable bucket seat; Figure 2a is a side elevation view of the bucket seat of the preferred wheelchair of Figure i; Figure 2b is a front view of the bucket seat of Figure 2a; Figure 3 is a side elevation view of the wheelchair of Figure 1 showing a preferred mechanism for adjusting the recline of the bucket seat; Figure 4 is a side sectional view of a preferred linkage mechanism used to adjust the tablet position and tilt angle whilst the bucket seat is being reclined; Figure 5 is a front elevation view of the tablet in its functional position, and showing an arrangement for attaching the tablet to the wheelchair; Figures 6a and 6b are respectively side elevation and front cross sectional views (along line A-A of Figure 6a) of the top linkage member which supports the tablet; Figure 7 is a side cross-sectional detail view through an arm of the chair showing the 20 location of the top linkage; Figure 7a is a plan view of an aperture through the upper part of the chair arm through which the tablet is attached to the top linkage; Figure 8 is a sectional front view of the tilt actuating arm and the lower part of the linkage arrangement in the left chair arm; 137227-1 8 Figure 9 is a sectional front view of the support arrangement for the right side of the chair; Figure 10 is a side elevation view of a second preferred embodiment wheelchair having a reclinable bucket seat; Figure 11 is a side elevation view of the wheelchair of Figure 10, showing part of an alternative preferred recline mechanism; Figure 12 is a side elevation view showing the rear tilt bracket lever arm of the wheelchair of Figure 10; Figure 13 is a side elevation view showing the first forward lever arm of the wheelchair 10 of Figure 10; Figure 14 is a side elevation view showing the second forward lever arm of the wheelchair of Figure 10; Figure 15 is a schematic side elevation view showing the reclining action of the wheelchair of Figure 10; Figure 16 is a side sectional view of an alternative preferred linkage mechanism used to adjust the tablet position and tilt angle whilst the bucket seat is being reclined; Figure 17 is a schematic view of the pivot attachments between the right side support arrangement, right side main drive arm, and right side rear tilt bracket with the seat support frame; Figure 18 is a sectional front view of the first forward lever arm and the lower part of the linkage arrangement in the left chair arm of the chair of Figure 10; Figure 19 is a sectional front view of part of the rear tilt bracket arrangement of the chair of Figure 10; 137227-1 9 Figures 20 and 21 are plan and left side elevation views respectively of a preferred base frame for the chair of Figure 10; Figures 22 and 23 are plan and left side elevation views respectively of a preferred seat support frame for the chair of Figure 10; Figure 24 is a side elevation view of a third preferred embodiment wheelchair having a reclinable bucket seat in an upright or forward position; Figure 25 is a side elevation view of the wheelchair of Figure 24 in a reclined position; Figure 26 is a side view of an alternative preferred linkage mechanism used to adjust the tablet position and tilt angle whilst the bucket seat is being reclined; Figure 27 is a forward-looking cross-sectional view of the tablet and its engagement with the chair; Figure 28a is a front elevation view of part of the tablet; Figure 28b is a forward-looking sectional view of part of the tablet and tablet support along line C-C of Figure 29; Figure 29 is a plan sectional view of the tablet support along line D-D of Figures 28a and 28b; and Figure 30 is a side sectional view of the tablet and tablet support along line E-E of Figure 29, showing the adjustability of the tablet.

Detailed Description of Preferred Forms While the preferred embodiments described below make reference to a wheelchair, it will be appreciated that at least some of the features described will have application in other types of chairs, for example, reclining armchairs or office task chairs. 137227-1 The preferred wheelchair shown in Figures 1 to 9 is generally indicated by reference number 1, and has a base frame 3 supporting a pair of enlarged rear wheels 5 and a pair of smaller front wheels 7. The front wheels are preferably pivotally mounted so that they 5 are rotatable about respective vertical axes, so that the wheelchair is easy to turn. If desired, a larger pair of occupant-propelled rear wheels may be provided.

Supported by the base frame is a bucket seat 9 having a seat part 11, a back part 13 and chair arm parts 15. Two handles 16 extend from the back part so that the wheelchair can 10 easily be pushed from behind. The bucket seat will generally be made of a hardwood frame having the shape as shown in Figures 2a and 2b, and will include suitable cushions (not shown) and will preferably be upholstered for comfort and appearance. The bucket seat may be made of any other suitable material, such as metal or a polymer plastic for example.

The bucket seat 9 is preferably mounted on a seat support frame 17 and is reclinable relative to the base frame 3 between a seating position as shown in solid lines, and a reclined position as shown in phantom. The recline mechanism will be described below with reference to Figure 3.

While a bucket seat is described as the preferred embodiment, the seat part 11 and back part 13 could be independently reclinable relative to the base frame 3 and to each other if further adjustability is desired. Alternatively, the movement between the seat part and 137227-1 11 back part could be synchronous, so that as the seat part tilts the back part also tilts. The seat part and back part could be arranged to move at different rates. Independent actuators could be provided for this purpose. The wheelchair also includes a tablet 19 mounted on a tablet support 21 and being in operative connection with the seat part 11 so 5 that as the seat part 11 reclines the tablet 19 moves with the seat part 11 but substantially maintains its orientation relative to the base frame 3 and/or the ground. The mechanism for achieving the tablet movement will be described below.

As can be seen in phantom lines in Figure 1, the tablet 19 is preferably also angularly 10 adjustable relative to tablet support 21 between a position 19a wherein it is substantially horizontal and a position 19b. This enables the tablet to be angled for reading, for example.

A leg rest 23 is pivotally attached to the seat 9 or seat support frame 17, and is pivotable 15 between a storage position as shown in solid lines and an extended position shown in phantom for supporting the legs of a chair occupant. The leg rest is supported on a curved support arm 25. With the leg rest 23 pivotally attached to the seat or seat support frame 17, as the seat reclines the leg rest adjusts in height relative to base frame 3. The leg rest can be adjusted to obtain a suitable angle between the seat part 11 of the seat and 20 the leg rest 23 in the reclined position.

Seat Recline Mechanism - First Embodiment 137227-1 12 As described above, the seat 9 is mounted so that it can recline relative to the base frame 3. The seat 9, and more particularly the seat part 11, is mounted on a seat support frame 17. With reference to Figure 3, a lever arm 27 is attached via a pivot 29 at or towards a rear end of the base frame 3 and is attached via a pivot 31 at or adjacent the rear end of 5 the seat support frame 17 in the vicinity of the rear lower corner of the bucket seat, i.e. the intersection between the seat part 11 and back part 13. This enables the rear corner to move in an arc around the lower pivot point 29. A tilt actuating arm 33 is attached via a pivot 35 towards the front end of the base frame 3 and to the seat support frame 17 at pivot 37 forward of pivot 31. The base frame 3, lever arm 27, tilt actuating arm 33 and 10 seat support frame 17 form a four bar linkage.

A drive mechanism which is preferably in the form of a twenty four volt electric actuator having a cylinder 39 and a piston 41 is attached via a pivot 43 at or towards a front end of the base frame 3 and attached via a pivot 45 at or towards a rear end of the seat support 15 frame 17, such that retracting the piston 41 into the cylinder 39 causes the seat to tilt from the sitting position shown in solid lines, to the reclining position shown in phantom. As can be seen from the Figure, retracting the piston 41 into the cylinder 39 causes the lever arm 27 to pivot forwards relative to the base frame about pivot point 29. That causes the seat support frame 17 and accordingly the seat base part 11 to move forward relative to 20 the base frame. Since the tilt actuating arm 33 is of fixed length, as the seat support frame 17 and the seat base parti 1 move forward, they also increase in angle relative to the horizontal, moving the chair towards the reclined position. 137227-1 13 As can be seen from the phantom lines, the maximum angle of tilt may be defined by the maximum retraction of the piston 41 into the cylinder 39. Alternatively or in addition, a stop could be provided to define the maximum recline. Rather than using an electric actuator, a hydraulic ram or similar could be provided.

An alternative drive mechanism could be used to adjust the recline angle of the seat and/or back part. For example, a chain drive mechanism could engage a gear on one of the components to adjust the angle of the seat and/or back part.

The forward movement of the seat 9 as it reclines means that an occupant's centre of gravity remains substantially the same relative to the base frame 3, thereby reducing the possibility of the chair tipping as an occupant reclines. Further, as can be seen from Figure 1, the rear part 13 of the chair does not drop significantly in height as the seat is reclined, meaning that an occupant's eye level does not drop dramatically. The four bar 15 linkage configuration provided also means that ground clearance can be minimised.

Controls will generally be provided to adjust the recline of the chair; these may be button actuators on a chair arm 15 for example. The wheelchair may be manually powered, or alternatively and more preferably, may be drivable by its own motive force and may 20 include an electric drive motor, for example. A single controller section may be provided on a chair arm to control the recline and motion of the chair, as well as the other features below. 137227-1 14 Tablet Arrangement - First Embodiment As described above with reference to Figure 1, the wheelchair has a tablet 19 mounted on a tablet support 21, so that a chair occupant can rest items such as books above the seat part 11. When the seat 9, or at least the seat part 11 in the case of a seat having 5 independently adjustable seat and back parts, is in the sitting position as shown in solid lines in Figure 1, the tablet 19 is positioned at a set height and angle of tilt relative to base frame 3 and/or the ground (which angle may be zero degrees as shown). The tablet support 21 may be height adjustable to enable the height of the tablet to be altered relative to the seat part 11. Telescopic support members may be provided for that 10 purpose. In a particularly preferred embodiment, the angle of tilt of the tablet relative to the tablet support may be adjustable. It is preferred that the included angle between part of the tablet support (or the base frame) and the tablet may be variable between about 0 degrees and about 45 degrees, and more preferably about 40 degrees. A document retainer or similar may be provided on the tablet. The angle of tilt of the tablet relative to 15 the tablet support 21 may be maintained through the use of a butterfly nut, adjusting knob or the like for example, or could be indexed in say 10 degree increments via a projection and recesses in the vicinity of a pivot joint 47 between the tablet support and the tablet.

As the seat 9, or at least the seat part 11, is reclined towards the position shown in 20 phantom in Figure 1, the tablet 19 moves with the seat part 11 to maintain its angle of tilt relative to the base frame 3 and/or ground. The phantom lines 19a show the position of the tablet when the chair is reclined, and phantom lines 19b show the tablet when manually pivoted about pivot joint 47 to adjust its angle relative to the tablet support 21. 137227-1 The mechanism for maintaining the tablet at its angle relative to the base frame 3 during reclining of the seat will now be described. With reference to Figure 4, a linkage arrangement indicated generally by reference numeral 50 is provided in the chair arm 15.

The tilt actuating arm 33 described above with respect to Figure 1 extends upwardly beyond the pivot point 37, and is preferably a rigid member having two angularly oriented parts 33a, 33b as shown. Part 33b forms a connecting part for the linkage arrangement. The pivot point 37 is located at or about the intersection of the two parts 33a, 33b. The upper end of the tilt actuating arm 33 is in pivotal connection with a first 10 linkage member 51 of the linkage arrangement 50. The first linkage member 51 floats relative to the chair arm 15, and its opposite end is pivotally connected to the lower end of a second linkage member 53. Second linkage member 53 is of similar configuration to tilt actuating arm 33, although is of smaller size, in that it has two angular parts 53a, 53b. The second linkage member 53 is rotatably mounted at pivot 55 to the chair arm at 15 or adjacent the intersection between the two angular parts 53a, 53b. The upper end of second linkage member 53 is pivotally attached to a third linkage member 57 which floats relative to the chair arm 15 and the opposite end of which is pivotally connected at pivot 58 to a tablet support linkage arm 59 which extends upwardly towards the upper edge of the chair arm 15. The tablet support linkage arm 59 is pivotally connected to the 20 chair arm 15 at pivot point 61 towards an upper end of the linkage arm.

Rather than using a linkage mechanism 50, a system of gears could be used to adjust the angle of the tablet relative to the seat part as the chair is reclined. Alternatively, a chain 137227-1 16 and sprockets, or a cable arrangement could be used for example, to adjust the angle of the tablet relative to the seat part as the chair (or at least the seat part) is reclined.

As shown in more detail in Figures 6a and 6b, tablet support linkage arm 59 includes a 5 connection part 63 and a housing part 65. The housing part 65 includes an aperture 67 in its upper end for receipt of the lower part of the tablet support 21. The tablet support 21 is preferably removable from the housing part 65 so that the tablet 19 can be removed from the wheelchair. The housing part 65 includes two outwardly extending shafts 69 which are receivable in apertures (not shown) in the chair arm to define the pivot point 10 61. The connection part 63 includes a boss 71 for pivotal connection to linkage member 57. An aperture 73 is also provided in connection part 63 for receipt of one end of a tension spring 75, the other end of which is attached to the chair arm as shown in Figure 4.

As the bucket seat 9 or at least the seat part 11 is tilted towards the reclined position shown in phantom in Figure 1, the relative angle between the tilt actuating arm 33 and the seat support frame 17 or chair base changes and moves to that shown in phantom in Figure 4. That causes the upper end of arm 33 to move forwardly in an arc as shown in phantom, which in turn moves the lower part of second linkage member 53 forward, 20 bringing the upper end thereof and, therefore, the lower end of the tablet support linkage rearwardly, as shown by the phantom arcs. It will be appreciated that the directions are relative to a seated occupant. The relative single between the tablet support linkage 59 and the chair arm 15 when the bucket seat is reclined is shown by line B-B in Figure 4. 137227-1 17 The base of the support arm 21 for the tablet 19 is positioned within housing part 65, such that as the seat 9 or seat part 11 tilts, the tablet 19 automatically counteracts the tilt to substantially the same extent, so that the tablet 19 largely maintains its position relative to 5 the support base 3 and/or ground during the reclining movement. The spring 75 reduces the slack in the movement of the linkage members. It is anticipated that the linkage mechanism will preferably enable the tablet to remain within about 1 degree of its initial angle relative to the base during recline of the chair. The maximum recline of the chair 9 and associated maximum change in angle of the tablet support linkage 59 may be in the order of about 30 degrees. As the tablet is spaced above the chair arm, as the chair reclines the tablet will move forward slightly relative to the seating surface. The movement will be in the order of about 50 to 75 millimetres, and may be suitable for making the tablet surface more accessible to a chair occupant in the reclined position.

As shown in Figure 7, a top plate 77 is provided above the tablet support linkage 59 to cover the recess in the chair arm. The top plate includes a central recess covered with an apertured elastic material section 79 such as rubber, to provide a weather seal around the tablet support 21 extending therethrough, but which allows movement of the tablet support as the chair tilts.

As shown, in the embodiment of Figure 8, instead of the tilt actuating arm 33 being a unitary member, it could be in the form of a tilt actuating arm assembly 33'. A central shaft 81, one end of which is threaded, is rigidly attached to the upper part 33b of the tilt 137227-1 18 actuating arm which extends into the chair arm 15 of the chair. The central shaft 81 extends through a bearing arrangement, generally indicated by reference numeral 83, which is mounted to the seat support frame 17. The bearing arrangement includes a housing 85 with a pair of spaced roller bearings 87 mounted therein. Spacers 89 are 5 positioned between the bearings 87 and the parts 33a, 33b of the tilt actuating arm. The lower part 33a of the tilt actuating arm is mounted on the shaft 81 and is maintained thereon with a cap screw 91 or similar fastener. A nut 93 is threaded onto the end of the shaft 81. It is not necessary for both sides of the chair to include a linkage arrangement to maintain the tablet at the desired angle.

The arrangement on the right side of the chair (direction relative to a seated chair occupant) is shown in Figure 9, and includes a tilt actuating arm 33" pivotally attached to the seat support frame 17 and base frame 3 via fasteners 95 extending through bearings 97. The fasteners are threaded into sleeves 99 which are mounted in the upper and lower 15 frame members. The arrangement on the right side enables movement between the base frame 3 and the seat support frame 17, and maintains them in the desired spaced apart configuration.

In its functional position, tablet 19 is supported mainly by support arm 21 as can best be 20 seen in Figure 5. However, a further support arm 101 may be used to provide further stability to the tablet. 13722 7-1 19 As shown in Figure 5, which is a view from the front of the chair, the tablet 19 is pivotally attached to tablet support 21 about pivot point 103 and is preferably moveable between the functional or use position, shown in solid lines, and the storage position to the outside of the chair arm 15. The tablet is preferably also pivotable about pivots 105 5 to change the angle of the tablet relative to the chair occupant as outlined above. Pivotally attached to the other end of the tablet 19 at pivot point 107 is the second tablet support 101 which is receivable in a recess in the right-hand side (relative to a seated occupant) chair arm to provide additional support for the tablet.

Both tablet supports 21 and 101 slot into apertures present in the chair arms of the chair. Tablet support 21 is mounted within housing part 65 of tablet support linkage 59 (shown located inside the left chair arm) when the tablet 19 is both in its use and storage positions. If a user wishes to remove the tablet from the wheelchair however, tablet support 21 can be lifted out of the housing part 65 of the tablet support linkage 59. 15 Alternatively, the tablet support 21 could be affixed to linkage 59, or could be formed as a unitary member therewith.

When the tablet 19 is to be moved to the storage position, the tablet can be tilted around pivot point 103 slightly, and the second tablet support 101 removed from the recess 109. 20 The second tablet support 101 may be folded under and located in a recess in the underside of the tablet and maintained therein by a retainer 111 which is preferably a clip. Other retainers, such as a swivel lock or a magnetic device for example, may also be 137227-1 used. The tablet 19 is then pivoted further about pivot point 103 and folded down the side of the chair arm 15 when not in use.

As described above with reference to Figure 1, the leg rest 23 is pivotally attached to the 5 seat support frame 17 as shown in Figure 3, and is pivotable between a storage position and a position for supporting the legs of a chair occupant.

Referring now to Figure 3, the leg rest is supported on a curved support arm 25 which is pivotally attached to leg rest pivot bracket 113 at pivot point 115.

A drive mechanism is provided to move the leg rest 23 between the two positions, and is preferably a twenty four Volt electric actuator 117 having a cylinder and piston which are pivotally attached to the seat support frame 17 and the leg rest 23 respectively.

Also shown in is a braking member 119 which is actuated automatically when the leg rest 15 23 is in its rearmost position. The leg rest pushes against a rod 121, which actuates the braking member causing it to engage against the wheel.

Figures 10 to 23 show components of an alternative preferred embodiment wheelchair. Unless described below, the components can be considered to be the same as those 20 outlined with reference to Figures 1 to 9, and like reference numerals are used to indicate like parts, with the addition of 200. The primary points of difference are in the recline mechanism and the linkage arrangement for maintaining the tablet at the desired angle. 137227-1 21 The preferred wheelchair has a base frame 203. The preferred base frame 203 is shown in detail in Figures 20 and 21. Supported by the base frame is a bucket seat 209 having a seat part 211, a back part 213 and chair arm parts 215.

The bucket seat 209 is preferably mounted on a seat support frame 217 and is reclinable relative to the base frame 203 between a seating position as shown in solid lines, and a reclined position as shown in phantom. The modified recline mechanism will be described below with reference to Figures 11-15.

The wheelchair again includes a tablet 219 mounted on a tablet support 221 and being in operable connection with the seat part 211 such that as the seat part 211 reclines the tablet 219 moves with the seat part 211 but substantially maintains its orientation relative to the base frame and/or the ground. The mechanism for achieving the tablet movement will be described below.

Seat Recline Mechanism - Second Embodiment As described above, the seat 209 is mounted so that it can recline relative to the base frame 203. The seat 209, and more particularly the seat part 211, is mounted on a seat support frame 217, which is shown in detail in Figures 22 and 23.

With reference to Figure 12, a rear tilt lever arm 227 is attached via pivot 229 at or adjacent a rear end of the base frame 203 and is pivotally attached via pivot 231 at or adjacent a rear end of the seat support frame 217 in the vicinity of the rear lower corner 137227-1 22 of the bucket seat. The rear tilt lever arm 227 is of different shape to the lever arm 27 of the first embodiment, and has a central portion and a rearwardly extending arm at either end of the central portion. The rear tilt lever arm 227 enables the rear corner to move in an arc around the lower pivot point 229, but to a different extent than the first 5 embodiment. The phantom lines represent the position of the rear tilt lever arm 227 when the chair is in the reclined position.

Rather than utilising a tilt actuating lever arm as described above, a first forward lever arm 233 as shown in Figure 11 and 13 is attached via pivot 235a towards the front end of 10 the base frame 201 and is pivotally attached via pivot 237a approximately half way along the seat support frame 217. The first forward lever arm 233 is articulated and 233 has an upper part 233a and a lower part 233c which are pivotally attached at pivot 233d. As can be seen from Figure 13, when the seat is in the sitting position, the lower part 233c of the first forward lever arm is substantially horizontal and the upper part 233a is substantially 15 vertical. During recline of the chair, the lower part 233c increases in angle relative to the base frame 203, and the upper part remains substantially vertical throughout the movement.

As shown in Figure 14, a second forward lever arm 233e is pivotally connected at pivot 20 235a towards the front end of the base frame 203. The second forward lever arm 233e is substantially V-shaped, and is connected via pivot 233g at its upper end to a main drive arm 233h. The main drive arm 233h extends upwardly and rearwardly from the pivot point 233g and is connected via pivot 233i at or adjacent the rear end of the seat support 137227-1 23 frame 217 (see Figure 15). As the seat is reclined, the main drive arm moves forward and down to the position shown in phantom in Figure 14, as the second forward lever arm 223e rotates anti-clockwise about pivot 235a.

It should be noted that Figure 13 excludes the second lever arm and main drive arm, and Figure 14 excludes the first lever arm for clarity. In the assembled wheelchair, the two lever arms will be present. The front pivots at the base frame for the first lever arm and the second lever arm are aligned at pivot 235a, and both lever arms may be welded to a sleeve for example (as indicated by component 240 for the other side of the chair in 10 Figure 17).

As can be seen from Figure 11, a drive mechanism which is preferably in the form of a twenty four Volt electric actuator having a cylinder 239 and a piston 241 is attached via pivot 243 at or towards a front end of part of the base frame 203 and attached via pivot 15 245 at or towards a rear end of the seat support frame 217 such that retracting the piston 241 into the cylinder 239 causes the seat to tilt from the sitting position shown in solid lines, to the reclining position shown in phantom. Retracting the piston 241 into the cylinder 239 causes the rear tilt lever arm 227 to pivot forwards about pivot point 229. This causes the seat support frame 217 and accordingly the seat base part 209 to move 20 forwardly relative to the frame. The first forward lever arm 233, second forward lever arm 233e and main drive arm 233h cause the seat to move forwardly and to increase in tilt angle as shown in phantom. The maximum angle is preferably about 30 degrees. The movement of the chair into the reclined position is shown schematically in Figure 15. 137227-1 24 Tablet Arrangement - Second Embodiment As described above, the wheelchair has a tablet 219 mounted on a tablet support 221, so that a chair occupant can rest items such as books above the seat part 211. When the seat 5 209, or at least the seat part 211 in the case of a seat having independently adjustable seat and back parts, is in the sitting position as shown in solid lines in Figure 10, the tablet 219 is positioned at a set height and angle of tilt relative to base frame 203 and/or the ground (which angle may be zero degrees as shown).

As the seat 209, or at least the seat part 211, is reclined towards the position shown in phantom in Figure 10, the tablet 219 moves with the seat part 211 to maintain its angle of tilt relative to the base frame 203 and/or ground. The phantom lines at 219a show the position of the tablet when the chair is reclined, and phantom lines 219b show the tablet when manually pivoted to adjust its angle relative to the tablet support 221.

The modified mechanism for maintaining the tablet at its angle relative to the base frame 203 will now be described, with particular reference to Figure 16. A linkage arrangement indicated generally by reference numeral 250 is provided in the chair arm 215. The first lever arm 233a described above with reference to Figure 11 is rigidly attached through a 20 bearing arrangement (in a similar manner to that described with reference to Figure 8) to an extension arm 233b which extends into the chair arm 215. The extension arm 233b forms a connecting part and is pivotally attached at or towards its upper end to a first linkage member 251 of the linkage arrangement. The first linkage member is pivotally 137227-1 attached at or adjacent its other end to a second linkage member 253. The first linkage member floats relative to the chair arm. The second linkage member 253 is rotatably mounted to the chair arm towards its central point, via pivot 255. The upper end of second linkage member 253 is pivotally attached to a third linkage member 257 which 5 floats relative to the chair arm 215 and the opposite end of which is pivotally connected to a tablet support linkage arm 259 which extends upwardly towards the upper edge of the chair arm 215 and is of the form described with reference to Figures 6a and 6b above.

As the bucket seat 209 or at least the seat part 211 is reclined towards the reclined 10 position shown in phantom in Figure 10, the relative angle between the first forward lever arm 233 and the seat support frame 217 or chair base changes and moves to that shown in phantom in Figure 16, which is preferably a change of about 30 degrees. That causes the extension arm 233b to move forwardly in an arc as shown in phantom, which in turn moves the lower end of the first linkage member 251 and the lower end of the second 15 linkage member 253 forwards, bringing the upper end thereof and, therefore, the lower end of the tablet support linkage rearwardly, as shown by the phantom arcs. It will be appreciated that the directions are relative to a seated chair occupant. The relative angle between the tablet support linkage 259 and the chair arm 215 when the bucket seat is reclined is shown by line B-B in Figure 16, and is an angle change of about 30 degrees 20 from the original position of the tablet support linkage 259.

The base of the support arm 221 for the tablet 219 extends through a plate as described above and is positioned within housing part of the tablet support linkage 259 as 137227-1 26 described for the first embodiment above. As the seat 209 or seat part 211 tilts, the tablet 219 automatically counteracts the tilt to substantially the same extent, so that the tablet 219 largely maintains its orientation relative to the support base 203 or ground during the reclining movement. The spring 275 reduces the slack in the movement of the linkage 5 members. It is anticipated that the linkage mechanism will preferably enable the tablet to remain within about 1 degree of its initial angle relative to the base during the recline of the chair. The maximum recline of the chair 208 and associated maximum change in angle of the tablet support linkage 259 may again be in the order of about 30 degrees. It is not necessary for both sides of the chair to include a linkage arrangement to maintain 10 the tablet at the desired angle.

The arrangement on the right side of the chair (direction relative to a seated chair occupant) is shown in Figure 17, and includes a first lever arm 233" pivotally attached to the seat support frame 217 at pivot point 237a and base frame 203 (pivotally via member 15 233c") at pivot point 235a. The arrangement on the right side enables movement between the base frame 203 and the seat support frame 217, and maintains them in the desired spaced apart configuration.

The arrangements of the second lever arm 233e and main drive arm 233h will generally 20 be the same on both sides of the chair. Figure 17 schematically shows sectional views of each point of attachment of the arms to the seat support frame 217, as well as a sectional view of pivot point 233g. The pivot points of the rear tilt bracket lever arm 227 and main drive arm 23 3h with the seat supporting frame 225 are aligned, with the respective pivot 137227-1 27 points 23 3i and 231 being provided by a bearing mounted on a bolt or similar extending through the seat supporting frame and through both pivots. A bearing arrangement is also provided to form the pivot point 233g between the main drive arm 233h and second lever arm 233e. The pivot point shown for the first lever arm 233" and seat supporting frame 5 217 is located forward of pivot points 233i and 231 as described with reference to Figure 10, and is in the form described with reference to Figure 17.

A guard plate 350 preferably extends upwardly from either side of the base frame 203 to reduce the chances of a person getting their fingers stuck in the moving components.

As shown in Figure 19, the pivot point 229 of the rear tilt lever arm 227 may be provided by the rear tilt lever arm 227 being rigidly attached to a sleeve 353 which is mounted for rotation relative to the base frame 203 as shown. The sleeve is shown as positioned in front of a rear cross member 203a of the base frame, and a central rod 355 extends across 15 the rear cross member, the sleeve being mounted for rotation on the rod 355 by bearings 357 as shown. It will be appreciated that only the right side is shown in Figure 19, but a similar arrangement will be provided on the left side of the chair, with the rod 355 preferably extending through both arrangements.

Figures 24 to 30 show components of an alternative preferred embodiment wheelchair. Unless described below, the components can be considered to be the same as those outlined with reference to Figures 1 to 9, and like reference numerals are used to indicate 137227-1 28 like parts (with the addition of 400). The primary points of difference are in the linkage arrangement for maintaining the tablet at the desired angle.

The wheelchair 401 has a base frame 403 supporting a pair of enlarged rear wheels 405 5 and a pair of smaller front wheels 407. The front wheels are preferably pivotally mounted so that they are rotatable about respective vertical axes, so that the wheelchair is easy to turn. If desired, a larger pair of occupant-propelled rear wheels may be provided.

Supported by the base frame is a bucket seat 409 having a seat part 411, a back part 413 10 and chair arm parts 415. Two handles 416 extend from the back part so that the wheelchair can easily be pushed from behind. The bucket seat will generally be made of a hardwood frame, and will include suitable cushions (not shown) and will preferably be upholstered for comfort and appearance. The bucket seat may be made of any other suitable material, such as metal or a polymer plastic for example.

The bucket seat 409 is preferably mounted on a seat support frame 417 and is reclinable relative to the base frame 403 between a seating position as shown in Figure 24, and a reclined position as shown in Figure 25.

While a bucket seat is described as the preferred embodiment, the seat part 411 and back part 413 could be independently reclinable relative to the base frame 403 and to each other if further adjustability is desired. Independent actuators could be provided for that 137227-1 29 purpose. Alternatively, the seat part 411 and back part 413 could be operatively engaged to move synchronously, either at the same rate or with differing rates if desired.

The wheelchair also includes a tablet 419 mounted on a tablet support 421 via adhesive, 5 welding, fasteners or the like, and which is in operative connection with the seat part 411 such that as the seat part 411 reclines the tablet 419 moves with the seat part 411 but substantially maintains its orientation relative to horizontal or the ground. The preferred connection between the tablet 419 and tablet support 412 is shown in Figures 28a and 29, and includes fasteners which extend into apertures in components 422a and 422b of the 10 tablet support. The mechanism for achieving the tablet movement will be described below.

As can be seen in phantom lines in Figure 30, the tablet 419 is preferably also selectively angularly adjustable relative to part of the tablet support 421 (or the base frame) between 15 a position 419a wherein it is substantially horizontal and a position 419b wherein its angle approaches up to about 45 degrees, and more preferably about 40 degrees. This enables the tablet to be angled for reading, for example. The mechanism for adjusting the angle will be described below.

A leg rest 423 is pivotally attached to the seat support frame 417 as shown in Figures 24 and 25, and is pivotable between a storage position as shown in solid lines and an extended position shown in phantom for supporting the legs of a chair occupant. The leg rest is supported on a curved support arm 425. With the leg rest 423 pivotally attached to 13722 7-1 the seat support frame 417, as the seat reclines the leg rest adjusts in height relative to base frame 403. The leg rest 423 can be adjusted to obtain a suitable angle between the seat part 411 of the seat and the leg rest 423 in the reclined position.

Seat Recline Mechanism - Third Embodiment As described above, the seat 409 is mounted so that it can recline relative to the base frame 403. The seat 409, and more particularly the seat part 411, is mounted on a seat support frame 417. With reference to Figures 24 and 25, a lever arm 427 is attached via pivot 429 towards a rear end of the base frame 403 and is attached via pivot 431 at or 10 adjacent the rear end of the seat support frame 417 in the vicinity of the rear lower corner of the bucket seat, i.e. the intersection between the seat part 411 and back part 413. This enables the rear comer to move in an arc around the lower pivot point 429. A tilt actuating arm 433 is attached via pivot 435 towards the front end of the base frame 403 and via pivot 437 to the seat support frame 417 forward of pivot 431. The base frame 15 403, lever arm 427, tilt actuating arm 433 and seat support frame 417 form a four bar linkage.

A drive mechanism which is preferably in the form of a twenty four volt electric actuator having a cylinder 439 and a piston 441 attached via pivot 443 at or towards a front end of part of the base frame 403 and via pivot 445 at or towards a rear end of the seat support 20 frame 417 respectively, such that retracting the piston 441 into the cylinder 439 causes the seat to tilt from the sitting position shown in Figure 24, to the reclining position shown in Figure 25. As can be seen from the Figure, retracting the piston 441 into the cylinder 439 causes the lever arm 427 to pivot forwards about pivot point 429. This 137227-1 31 causes the seat support frame 417 and accordingly the seat base part 411 to move forwardly relative to the frame. Since the tilt actuating arm 433 is of fixed length, as the seat support frame 417 and the seat base part 411 move forward, they also increase in angle relative to the horizontal, moving the chair towards the reclined position.

As can be seen from Figure 25, the maximum angle of tilt may be defined by the maximum retraction of the piston 441 into the cylinder 439. Alternatively or in addition, a stop could be provided to define the maximum recline. Rather than using an electric actuator, a hydraulic ram or similar could be provided.

The forward movement of the seat 409 as it reclines means that an occupant's centre of gravity remains substantially the same relative to the base frame 403, thereby reducing the possibility of the chair tipping as an occupant reclines. Further, as can be seen from Figure 24, the back part 413 of the chair does not drop significantly in height as the seat 15 is reclined, meaning that an occupant's eye level does not drop dramatically. The four bar linkage configuration provided also means that ground clearance can be minimised. Controls will generally be provided to adjust the recline of the chair; these may be button actuators on a chair arm 415 for example. The wheelchair may be manually powered, or alternatively and more preferably, may be drivable by its own motive force and may 20 include an electric drive motor, for example. A single controller section may be provided on a chair arm to control the recline and motion of the chair, as well as the other features below. 137227-1 32 Tablet Arrangement - Third Embodiment As described above with reference to Figure 24 and 25, the wheelchair has a tablet 419 mounted on a tablet support 421, so that a chair occupant can rest items such as books above the seat part 411. When the seat 409, or at least the seat part 411 in the case of a 5 seat having independently adjustable seat and back parts, is in the sitting position as shown in Figure 24, the tablet 419 is positioned at a set height and angle of tilt relative to base frame 403 and/or the ground (which angle may be zero degrees as shown). It is preferred that the included angle between part of the tablet support (or the base frame) and the tablet may be variable between about 0 degrees and up to about 45 degrees, and 10 more preferably about 40 degrees. The tablet may be lockable in intermediate positions, or alternatively mav be lockable onlv in the lowered CO degrees') and raised (maximum * * ^ v c / v tilt) positions. A document retainer or similar may be provided on the tablet.

As the seat 409, or at least the seat part 411, is reclined towards the position shown in 15 Figure 25, the tablet 419 moves with the seat part 411 to maintain its angle of tilt relative to the base frame 403 and/or ground.

The mechanism for maintaining the tablet at its angle relative to the base frame 403 during tilting of the seat will now be described. With reference to Figure 26, a linkage 20 arrangement indicated generally by reference numeral 450 is provided in the chair arm 415. Tilt actuating arm 433 described above with respect to Figure 24 and 25 incorporates a tablet lower linkage attachment bracket 433a which forms a connecting part for the linkage arrangement. The tablet lower linkage attachment bracket 433a is in 137227-1 33 pivotal connection with a member 451 of the linkage arrangement 450. The linkage member 451 floats relative to the chair arm 415, and its opposite end is pivotally connected to the lower end of a tablet support bush arm 459. The tablet support bush arm 459 carries a tablet support bush 460 (as shown in Figure 27) which is pivotally 5 connected to the chair arm 415 as will be more apparent from Figure 27..

As shown in more detail in Figure 27, tablet support bush 460 includes an aperture 460a in its inner end for receipt of a tablet support tongue 421a, which extends from one end of a main tablet support part 421b which in the preferred embodiment is in the form of a 10 hollow shaft. The tablet support tongue 421a is preferably removable from the aperture 421a so that the tablet support 421 and tablet 419 can be removed from the wheelchair.

As the bucket seat 409 or at least the seat part 411 is reclined towards the reclined position, the relative angle between the tilt actuating arm 433 and the seat support frame 15 417 or seat part 411 changes and moves from that shown in Figure 24 to that shown in Figure 25. That causes the bracket portion 433a to move to the position shown in phantom in Figure 26, which in turn moves the lower part of linkage member 451, bringing the upper end thereof and, therefore, the lower end of the tablet support bush arm 459 down slightly relative to the seat support frame 417 but away from the base 20 frame 403. The angle of the tablet support bush arm 459 relative to the base frame 403 stays substantially the same. 137227-1 34 The linkage arrangement 450 is configured such that as the seat 409 or seat part 411 tilts, the tablet 419 automatically counteracts the tilt to substantially the same extent, so that the tablet 419 largely maintains its angular position relative to the base frame 403 and/or ground during the reclining movement. It is anticipated that the linkage mechanism will 5 preferably enable the tablet to remain within about 1 degree of its initial angle relative to the base during the recline of the chair. The maximum recline of the chair 409 may be in the order of about 30 degrees.

The inner side of the opposite chair arm includes a further recess or tablet support bush 10 462 with an inwardly-facing aperture 462a. The tablet support and thereby the tablet are held in position by a locking pin 421c extending into the bush 462 and the tongue 421a extending into the bush 460. A projection 42Id extends from the pin 421c and extends through a slot in the shaft 421b to enable the pin it to be moved by a user. To remove the tablet from the chair, the pin is retracted and that end of the tablet is lifted upwardly as 15 indicated by the arrow in Figure 27. The curved recess in the top of the tongue 421a enables the tablet to be tilted relative to the bush 460 and thereby withdrawn. There is preferably a similar arrangement of bushes provided on the rear side of the chair back to store the tablet when not in use. In one embodiment, the pin may be lockable in the extended position to prevent exit from the chair by users with limited mental capacity.

A preferred mechanism for selectively adjusting the angle of the tablet relative to the tablet support (or base frame) will now be described with reference to Figures 29 and 30. The tablet support 421 includes the hollow shaft 421b as mentioned above. A pair of 137227-1 support members 42Id extend forwardly and rearwardly from the shaft 421b. A pair of forward support arms 422 are pivotally attached at pivots 422a at or toward the front end of each of the support members 42Id, and are pivotally attached to the tablet 419 at pivots 422b. A pair of rear support arms 424 are pivotally attached to the support 5 members 42Id rearwardly of the hollow shaft 421b at pivots 424a (which are defined by a shaft in the preferred embodiment), and are pivotally attached to the tablet 419 at pivots 424b. It can be seen that the rear support arms 424 which are configured to be positioned closest to a chair occupant are shorter in length than the forward support arms 422 which are configured to be positioned farthest from a chair occupant. Each support member 10 42Id, the tablet 419, a forward support arm 422 and a rear support arm 424, form a four bar linkage. By this arrangement, the tablet 419 can be lifted and moved forward relative to the support members 42Id, with a corresponding increase in angle relative to the support members 42Id.

The preferred wheelchairs described above allow a user to recline in the chair, whilst minimising movement between the seat part and the tablet and maintaining the tablet substantially in its original orientation relative to the ground or base frame.

Preferred forms of the invention have been described by way of example only and it 20 should be appreciated that modifications and additions thereto may be made without departing from the scope of the invention. 137227-1 36 For example, the linkage arrangements could alternatively be provided in the right-hand side chair arm, with the second tablet support being receivable in a recess in the left-hand side chair arm.

Further, a seat support frame would not be necessary in some embodiments, rather the levers could be connected directly to the seat part. 137227-1

Claims (30)

37 WHAT I CLAIM IS:

1. A chair including: a base frame; a seat part and a back part supported from the base frame, the seat part and back part being reclinable between a first seating position 5 and a second reclined position; and a tablet supported by the chair and configured such that as the seat part is reclined the tablet moves with the seat part and substantially maintains its angle relative to the base frame and/or ground.

2. A chair as claimed in claim 1, wherein the chair includes a bucket seat with the 10 seat part and back part being arranged at a predetermined angle, such that the seat part and back part are reclinable as a single unit.

3. A chair as claimed in claim 2, wherein the bucket seat is arranged so that as it moves from a seating to a reclined position, its pivot point moves forward and downward 15 to maintain an occupant's centre of gravity substantially in the same position relative to the base frame.

4. A chair as claimed in claim 1, wherein the seat part and back part are arranged to move independently. 20

5. A chair as claimed in any one of the preceding claims, wherein the seat part is supported by a seat support frame. 137227-1 38

6. A chair as claimed in any one of the preceding claims, including a drive mechanism to selectively move the seat part between the seating position and the reclined position. 5

7. A chair as claimed in claim 6, wherein the drive mechanism includes an electric actuator, one end of which is operatively connected to the base frame and the other end of which is operatively connected to the seat part and/or seat support frame.

8. A chair as claimed in any one of the preceding claims, wherein a rear lever arm is 10 pivotally connected at or adjacent a rear part of the base frame at a lower rear lever arm pivot and pivotally connected at or adjacent a rear part of the seat part or seat support frame at an upper rear lever arm pivot, such that the seat part is arranged to move about a radius defined by the rear lever arm.

9. A chair as claimed in claim 8, wherein a tilt actuating arm is pivotally connected to the base frame forward of the lower rear lever arm pivot and pivotally connected to the seat part or seat support frame forward of the upper rear lever arm pivot, such that the intersection of the seat part and back part moves forward in an arc around the lower rear lever arm pivot and the seat part tilts towards the reclined position as the seat is reclined.

10. A chair as claimed in claim 9, wherein the rear lever arm, the base frame, the tilt actuating arm, and the seat part or seat support frame forms a four bar linkage. 39

11. A chair as claimed in claim 10, including a pair of rear lever arms, one on either side of the chair, and a pair of tilt actuating arms, one on either side of the chair; wherein the rear lever arms, tilt actuating arms, base frame, and seat part or seat support frame form two four bar linkages. 5

12. A chair as claimed in any one of the preceding claims, including a linkage arrangement which operatively connects the tablet to the seat part.

13. A chair as claimed in claim 12, including a tilt actuating arm pivotally connected 10 to the seat part or seat support frame, wherein the tilt actuating arm includes a connecting part extending forward of its pivot point with the seat part or seat support frame.

14. A chair as claimed in claim 13, wherein the two parts of the tilt actuating arm are angularly oriented. 15

15. A chair as claimed in claim 13 or 14, wherein the connecting part extending forward of the seat pivot is pivotally connected to a linkage member.

16. A chair as claimed in claim 15, wherein the linkage member is pivotally 20 connected to a tablet support arm for supporting the tablet.

17. A chair as claimed in claim 16, wherein the tablet support arm includes a bush arranged for receipt of part of a tablet support. 137227-1 40

18. A chair as claimed in claim 16 or 17, wherein the linkage member is floating relative to the seat part and is held between the connecting part of the tilt actuating arm and the tablet support arm. 5

19. A chair as claimed in any one of claims 12 to 18, including a tablet support which is configured to support the tablet from the linkage arrangement.

20. A chair as claimed in claim 19, wherein the angle of the tablet relative to part of 10 the tablet support and/or base frame is selectively adjustable.

21. A chair as claimed in claim 20, wherein a first relatively short lever arm is pivotally connected to the tablet support and the tablet, and a second relatively long lever arm is pivotally connected to the tablet support and the tablet forward of the first 15 relatively short lever arm, the lever arms configured such that the tablet can be moved from a position substantially parallel with part of the tablet support and/or base frame to a position wherein the part of the tablet toward the front of the chair is raised relative to the part of the tablet toward the rear of the chair. 20

22. A chair as claimed in claim 21, wherein two first lever arms and two second lever arms are pivotally connected to the tablet support and tablet. 137227-1 41

23. A chair as claimed in any one of claims 20 to 22, wherein the angle between the tablet and part of the tablet support and/or base frame is adjustable by up to about 45 degrees. 5

24. A chair as claimed in any one of claims 12 to 23, wherein the chair includes chair arms which are moveable with the seat part, and the linkage arrangement is provided in at least one of the arms such that as the seat part is reclined, the tablet moves with the seat part and substantially maintains its angle relative to the base frame and/or ground. 10

25. A chair as claimed in any one of the preceding claims, wherein the tablet and/or tablet support are removable from the chair.

26. A chair as claimed in any one of the preceding claims, including a leg rest which is configured to move with the seat part as the seat part is reclined. 15

27. A chair as claimed in claim 26, wherein the angle of the leg rest relative to the seat part is selectively variable.

28. A chair as claimed in any one of the preceding claims, wherein the chair is a 20 wheelchair.

29. A chair substantially as herein described with reference to the accompanying drawings. 137227-1 42

30. A chair as claimed in claim 1, substantially as herein described with reference to any embodiment disclosed. 137227-1