GB2499023A

GB2499023A - Collapsible wheelchair for accessing a toilet and shower

Info

Publication number: GB2499023A
Application number: GB1201927.9A
Authority: GB
Inventors: David Mark Williams; Nigel Harrison
Original assignee: University of Sheffield
Current assignee: University of Sheffield
Priority date: 2012-02-03
Filing date: 2012-02-03
Publication date: 2013-08-07
Also published as: GB201201927D0; WO2013114133A1

Abstract

A collapsible wheelchair for accessing a shower and toilet comprises: a seat 12 having a toilet aperture 61; a pair of footrests 20a,b, one mounted to each side 14a,b of the wheelchair, and each being pivotally connected to the frame to be movable between an erected condition in which the footrests are coupled to one another (as shown), and a stowed condition in which each footrest lies substantially wholly within parallel boundary planes defined by a main wheel 16 and the side of the wheelchair frame (shown in Fig. 7); and a pair of pivotally interconnected bows 42a,b (braces) extending between opposing sides of the wheelchair, the bows being connected to the footrests in an erected condition and being shaped to allow the wheelchair to be reversed over a toilet bowl, and wherein the bracing bows also are capable of being moved into a stowed side-by-side configuration once the seat has been released from one side of the chair and the footrests folded into a stowed condition (as shown in Fig. 9). The cross bows 42,a,b are connected to the footrests by a link member, e.g. latch pin 40, and once coupled form a triangulated three dimensional structure with the seat 12 and the footrests 20a,b.

Description

1

Wheelchair

[0001] This invention relates to a wheelchair for use by disabled people.

5 BACKGROUND

[0002] Wheelchairs permit mobility for those who do not have use, or full use, of their legs. Wheelchairs need to be robust to withstand their frequent use. They need to be comfortable, given the extended periods of time a person may sit in them. Consequently, flexibility in seat and backrest, quite possibly with (soft) padding in places, is often desirable. Wheelchair

10 structures, however, need to be rigid, so that the user can reliably shift weight, or so that the chair can be maneuvered by pressure on one point, without deflecting the entire structure. Indeed, the use to which wheelchairs are put dictates a general requirement for high strength and rigidity in construction.

[0003] Moreover, general use imposes few limitations on size or construction of the

15 wheelchair, beyond a need to meet basic requirements such as to be able to access standard doorways, or not be so heavy as to be impractical. However, there are at least two situations where wheelchairs for general use fail to accommodate frequent needs of their users. The first is in accessing a toilet, and the second is in accessing a shower.

[0004] Using a toilet is still an occasion for a disabled person when human dignity is

20 challenged by the unfortunate circumstance the person finds themselves in. One option is that they must find a toilet that has been modified to enable wheelchair users to transfer themselves to the toilet bowl. Such toilets are now required in public places, but not everywhere. Alternatively wheelchair users require personal assistance to use a toilet, (from being undressed through to transferring to and from a toilet bowl).

25 [0005] In the context of the present invention a standard toilet bowl is hereby defined as one that substantially fits within the confines of a complex shape consisting of:

a rear planar wall, against which the bowl is mounted a horizontal, planar floor, under the bowl a cuboidal pedestal on the floor and in connection with the wall and having a semi-30 cylindrical nose at the end remote from the wall;

and a solid cylinder, seated on one end on the pedestal and centred on said nose, wherein the pedestal has a width of between 15 and 25 cm and a height of between 10 and 25 cm, and the solid cylinder has a height of between 10 and 25 and a diameter between 30 and 35 cm, the overall height of the solid cylinder and pedestal being between 30 and 35 cm.

35 [0006] Figures 1a and b illustrate this arrangement.

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[0007] Clearly, a toilet having precisely these dimensions and shape would be an unusual construction. However, the present invention is predicated on accommodating a toilet bowl that has this fundamental shape and dimensions. To that end, this shape and dimension (and with which the present invention is concerned) is hereinafter referred to as "the standard toilet bowl".

5 [0008] The second and perhaps more common problem, given the increasing availability of toilets suitable for wheelchair users, is in relation to wheelchair users taking a shower. Wheelchairs are not generally suitable for use in showers and there are three primary reasons for this. The first is that they are not suitable for wetting with hot soapy water. Secondly they are usually too big to be maneuvered into a shower.

10 [0009] Accordingly, there is requirement to provide a wheelchair construction that is capable of meeting these needs.

[0010] US2002/024196 discloses a wheelchair construction suitable for the proposed applications but is still substantially bulky and evidently heavy so that it most likely could not be easily manipulated by the disabled person themselves. It is an object of the present invention to

15 provide an improved design of wheelchair for use in toilets and shower rooms.

BRIEF SUMMARY OF THE DISCLOSURE

[0011] In accordance with the present invention, there is provided a collapsible wheelchair for accessing a shower and toilet comprising:

20 a seat having a toilet aperture and defining a seat plane;

two sides, each having a main wheel rotatably mounted thereon for supporting the majority of the weight of the chair and a person seated thereon when the chair is in an erected condition, the seat being adapted for releasable connection to one or both sides;

a footrest, pivotally mounted at one end to a lower front edge of each side, whereby 25 each footrest is foldable relative to the side:

a) into a stowed condition in which it is substantially wholly within parallel boundary planes defined by an inner surface of the side and the main wheel mounted on said side; and b) into an erected condition in which its other end is releasably connected to the other 30 end of the other footrest and is substantially perpendicular to said boundary planes and parallel said seat plane, which in said erected condition of the chair is arranged substantially perpendicular to said boundary planes a pair of bows interconnected by a link between them at one end of each bow and connected to a respective one of said sides at their other end, whereby:

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in the erected condition, said link is fixed adjacent said connection between said other ends of the footrest to permit the bows and footrests to act as braces holding the sides in relative juxtaposition with the seat, the bows being so shaped that the chair may be reversed over a standard toilet bowl as hereinbefore defined through a rear opening of the chair defined 5 by the seat and sides until the toilet aperture is substantially vertically aligned with the bowl of the toilet; and in the stowed position, said link permits folding of the bows so that said sides may be drawn into a side-by-side configuration after release of said seat from at least one side and after said foot rests have been folded into their stowed position 10 wherein the sides, seat, footrests and bows provide a triangulated, three-dimensional structure in the erected condition of the wheelchair.

[0012] In this way, the wheelchair of the present invention in said stowed position is essentially "flat-packed" into a sufficiently small package that an active wheelchair user can a) carry the wheelchair of the present invention around with him or her, and b) assemble it

15 themselves without assistance for use in going to the toilet or taking a shower, particularly in environments whereby the facilities at hand have not been specially adapted for wheelchair users. Yet, in the erected condition, the triangulation of the structure when assembled provides a rigid construction where the bows provide both lateral support for the sides with respect to the seat and both frontal and downward support for the footrests. The bows define a triangulation 20 plane that is inclined with respect to the seat plane and therefore has components of support between the sides and footrests in both the vertical plane and horizontal (the seat) plane.

[0013] The exact construction of the standard toilet bowl is, if course, unconnected with the present invention beyond defining the minimum capability in terms of rear access that the chair needs to meet. Consequently, toilets that the chair might access in use may be either pedestal

25 or wall mounted toilets.

[0014] While the sides of the wheelchair, and thus most likely the plane of rotation of the main wheels, in the erected condition of the chair are substantially vertical (assuming that the seat is horizontal) such substantiality should not be taken to exclude the possibility of a degree of inclination of the sides and/or main wheel planes. This is common in wheelchairs, particularly

30 sporting wheelchairs, where the main wheels are often splayed outwardly to improve stability. Thus the sides (and/or main wheels) may be flared outwards by as much as 10 degrees without departing from the substantial vertically. Such flaring will also serve the purpose of restricting the possibility of inward forces being generated in the chair in its erected position.

[0015] Preferably, the seat is permanently pivotally connected to one side and pivots from the 35 erected position to the stowed position to between the sides.

[0016] In one embodiment, the sides and seat are each a single casting of metal. The metal

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needs to be as light and strong as possible, and resistant to water. Aluminium is an obvious low-cost choice of material, or titanium. Preferably, however, the sides and seat are each moulded from a composite material comprising carbon-fibre.

[0017] Preferably, a back support and side supports are provided to help support a disabled 5 person seated on the wheelchair. Preferably, armrests comprise a curved rest component connected to spoke components pivoted to the side between the side and the main wheel mounted on said side, whereby the armrest pivots between an erected position in which the rest component is above the level of the seat when the wheelchair is in its erected condition and a stowed position in which the arm rest is substantially within the peripheral footprint of the side 10 and its main wheel. The peripheral footprint of a component is defined as the largest surface area its outline projects onto a flat surface.

[0018] Preferably, the back support comprises a pair of rods pivoted to the seat at the rear end of the seat, wherein the rods pivot between an erected position in which the rods are substantially perpendicular to the seat and a stowed position in which the rods are substantially

15 coplanar with the seat, a flexible sheet being strung between the rods against which a user of the wheelchair may lean when the chair and backrest is in their erected condition. Preferably, a hinge bracket for each rod is attached to the seat providing a hinge axis positioned at a front side of the rod near its base, wherein the base of the rod abuts the bracket or seat in said erected position limiting rotation of the rod beyond said erected position.

20 [0019] Preferably, the wheelchair further comprises a detachable toilet pan, and means are provided for connection of the pan under the seat, whereby the wheelchair may be rendered as a commode. Such means may comprise a horizontally disposed slot on each side, into which slot edges of the pan may be slid from behind or in front of the chair.

[0020] In the erected condition, it will be apparent from the foregoing that the sides and seat 25 are braced by the bows and footrests.

[0021] Preferably, the connection of said other ends of the bows to the sides of the wheelchair are not further forward of the sides than the axis of the main wheels. Here, forward means with respect to the front of the wheelchair where the footrests are located. Preferably, the vertical height above the ground of the connection of the bows to the sides is more than their

30 connection to the footrests. In one embodiment, the connection is close to the axle of the main wheels.

[0022] Preferably, said bows are pivoted to the sides about side axes, each providing a single degree of freedom. Preferably, said bows are pivoted to the sides about sides axes that are a) substantially horizontal and b) substantially parallel to said sides.

35 [0023] Preferably, said one ends of said bows are pivoted together about a link axis that is

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parallel to said side axes. Said one ends of said bows may be pivoted together about a link axis that provides a single degree of freedom. The link between said bows may be a discrete component, being a link member, to which each bow end is pivoted.

[0024] Preferably, the link member, and each footrest at each end, has a simple through-bore, 5 all three of which through-bores may be aligned in the erect condition of the wheelchair and though which through-bores a latch pin may be inserted to lock all three components together. In one embodiment the latch pin is of the type comprising a rod having a knob at one end and a protrudable key at the other end on release of a button on the knob, and the bores are of the same diameter as the rod, whereby the rod on full insertion of the latch pin in the through-bores 10 and on release of the button engages the protrudable key to lock the rod in the through-bores and to lock the footrests and bows together.

[0025] In one embodiment, the knob at its top end has is a central sprung loaded shaft. Pressing this allows two balls forming said protrudable key at the other end to retract into the body allowing it to be withdrawn from the plain holes in both footrests and the link. The strength

15 needed is to resist shear forces created as the footrests move outwards and this is a simple and effective connection.

[0026] Said bows are preferably arcs of a circle. Preferably, said bows at their pivot with the sides are substantially tangential with respect to said boundary planes and at their interconnection through said link are tangential to a plane perpendicular to said boundary and

20 seat planes.

[0027] Preferably, each foot rest comprises a mounting component and a foot component, the two components being pivoted to one another about a foot axis, and wherein the mounting component is pivoted to the lower front edge of the respective side about a mounting axis substantially perpendicular to the boundary plane.

25 [0028] In one embodiment a spring-loaded locking pin is arranged between said mounting component and said side along an axis parallel said mounting axis and is adapted selectively to release and lock the mounting component and side. Preferably, each mounting component also mounts a caster wheel to support a minor amount of the weight of the chair and a person seated thereon when the chair is in an erected condition.

30 [0029] Preferably, the seat comprises four blind slots on its underside, each adapted to receive one of a pair of noses formed along a top edge of each side, latches being provided to retain the seat in engagement with sides whereby movement of one with respect to the other is prevented:

in the boundary plane by the latch on the one hand and the noses engaging the blind 35 bases of the slots; and

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in the seat plane, by the sides of the noses engaging the sides of the slots.

[0030] Preferably, the seat comprises a ring forming the toilet aperture and four ears at four corners of the seat, each ear having one of said blind slots. Preferably, each ear comprises a pair of limbs, one being tangential a side of said aperture and the other being tangential to a

5 rear or front end of said aperture.

[0031] The present invention therefore provides a wheelchair of minimalist construction so that it can be made light enough for it to be carried easily by a disabled person in their everyday wheelchair, but which is strong enough for use as a wheelchair when erected and compact enough to be maneuvered inside a shower cubicle yet be positioned over a toilet. Moreover it is

10 of such construction that its assembly, disassembly and stowage is possible for a person having restricted maneuverability.

DETAILED DESCRIPTION OF AN EXAMPLE

[0032] An embodiment of the invention is further described hereinafter with reference to the 15 accompanying drawings, in which:

Figure 1a and b are a perspective and planned view of a typical toilet embodying the shape and dimensions of a standard toilet bowl as herein defined;

Figures 2 to 11 are perspective views in different detail of a wheelchair in accordance with the present invention ranging from an assembled erected condition in Figure 2 to a 20 dismantled, stowed condition in Figure 11;

Figure 12 is a close-up view of a latch-pin employed;

Figure 13 is a perspective view of the wheelchair of Figures 2 to 11 with armrests and back support: in stowed positions; and

Figure 14 is detail XIV in Figure 2.

25 [0033] The reader will be aware that toilet bowls come in a great variety of shapes and sizes, some which the present invention may not be able to accommodate. It is an object of the present invention to at least accommodate all toilet bowls that conform to the shape and dimensions of the standard bowl defined above and explained further below. That is to say, toilets that fit within the confines of the envelope of the standard toilet as herein defined. Thus, 30 in Figure 1a, a toilet 1 comprises a bowl 2 and a pedestal 3. The pedestal extends from a wall 4 and has dimensions between 15 and 25 cm in width. Its end is terminated by a semi-cylindrical nose 5 of radius 7.5 to 12.5 cm.

[0034] The bowl 2 also extends from the wall 4 and has a width of between 30 and 35 cm and likewise terminates in a semi-cylindrical nose 6 of diameter 10 to 15 cm, the nose 6 extending 35 beyond the nose 5 by between 10 and 15 cm. The height of the pedestal 3 is between 10 and

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25 cm and likewise the height of the bowl 2 is between 10 and 25 cm. However, the overall combined height of the bowl 2 and pedestal 3 is between 30 and 35 cm.

[0035] As already mentioned, some toilet bowls currently available on the market will not fit within the envelope defined above. If they do not, a wheelchair in accordance with the present

5 invention may still accommodate some of them. However, the present invention is only concerned with toilet bowls that do fit within these confines and any wheelchair that does not accommodate such a toilet bowl is outside the scope of the present invention.

[0036] Turning to the wheelchair of the present invention, a wheelchair 10 is illustrated in Figures 2 to 11 and 13 - in Figures 2 and 3 in fully assembled state, and in Figures 4 to 11 in

10 various stages of disassembly.

[0037] Referring to Figure 2, the wheelchair 10 comprises a seat 12 and two sides 14a,b which are each mirror images of one another. Each side 14a,b mounts a main wheel 16 on an axle 18 fixed in the respective side 14a,b.

[0038] Each side 14a,b has a footrest 20a,b. Each footrest comprises a mounting component 15 22a,b connected to an end 14c of each side 14a,b, and a foot component 24a,b. The foot components 24a,b are each pivotably mounted on the end of the mounting component 22a,b about axes 26 that are substantially parallel the ground and parallel the plane of the sides 14a,b. The degree of freedom that the pivot about the axes 26 permits is between a substantial right angle as shown in Figure 2 and an aligned position as shown in Figure 5. At the pivot end 20 of the mounting component 22a,b is fixed a caster wheel 28.

[0039] The free ends 30 of the foot components 24a,b each have a plain bore 32 (see Figure 5) adapted to overlap with each other when in the position shown in Figure 2. The plain bores 32 are adapted to receive the shaft 34 of a latch pin 40 (see Figure 12 for more detail). The latch pin 40 comprises a knob 36 having a central push button 38 that is spring loaded

25 outwardly to the position shown in Figure 12. When depressed, a rod (not visible and extending down the shaft 34) releases protrudable keys 39 in the form of balls. When the key is retracted, the shaft 34 can be inserted through the plain bores 32 until the balls 39 extend beyond the footrests, whereupon release of the button 38 causes the balls 39 to protrude outwardly preventing withdrawal of the latch pin 40 and locking the footrests 24a,b together, as shown in 30 Figure 2. Such a latch pin is currently available from Wixroyd.International Limited (www.wixroyd.com/en).

[0040] Bows 42a,b are interconnected at their ends 46 by a link member 44. Each end 46 is pivoted to the link member about parallel axes 48, (which, to all intents and purposes, is a single composite axis). Such axes 48 are substantially parallel the axes 26. At their other ends 52,

35 the bows 42a,b are connected to the sides 14a,b, again about pivot axes 56 which are

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substantially parallel the axes 48. The bows 42a,b are substantially arcs of a circle, such that the ends 52 are substantially tangential with respect to the plane of the sides 14a,b and the ends 46 are substantially tangential with respect to a line joining the foot components 24a,b. The link member 44 is also provided with a plain bore (not visible) to receive the shaft 34 of the 5 latch pin 40. Thus, the latch pin 40 serves to connect both the bows 42a,b and the footrests 20a,b with a single connection. The connections of the rear ends 52 to the sides 14a,b are preferably as far back towards the rear of the chair 10 as possible. However, they are at least not further forward than the axle 18.

[0041] Returning to Figure 2, the seat 12 comprises a single casting of a light and strong 10 metal, such as aluminium, titanium or an alloy, although it may also be constructed from a composite material such as carbon fibre. With reference to Figure 8, the seat 12 comprises a toilet aperture ring 60 (having a toilet aperture 61) and four ears 62a-d. Each ear 62a-d comprises a pair of limbs 64 diverging from the ring 60 and connected at corners 66. The seat 12 is designed to facilitate the wheelchair user's 'bowel-care' processes that they might have to 15 carry out. Obviously, these do not necessarily require the wheelchair to be in a shower or to be over a toilet employing the commode function. Nevertheless, the wheelchair 10 and its seat 12 permit the user to gain access under the chair seat, from all directions around the seat, to complete required tasks. The arches in all of the sides of the seat between the ears 62a-d are not just for reduction of weight. Preferably, the average width of the rim of the aperture 61 is 20 less than 10 (or even 7) cm between connections with the limbs 64.

[0042] Each corner 66 is provided with a catch 68, the sides 14a,b being provided with four corresponding latches 70. The underside of the seat 12 (not visible) incorporates four blind slots adapted to receive noses 72 formed as parts of the sides 14a,b. When the wheelchair 10 is shown in the position illustrated in Figure 8, the seat 12 can be placed on the four noses 72

25 engaging the blind slots in the seat. When the latches 70 are engaged with the catches 68,

they lock the seat in place.

[0043] Returning to Figure 2, it can now be seen that a stable arrangement is provided, in that the seat 12 is in a rigid horizontal seat plane and the engagement of the noses 72 with the slots in the seat 12, together with the latches 70 engaging the catches 68, lock the sides 14a,b with

30 respect to the seat against relative movement in the seat plane 12, as well as in perpendicular directions thereto. The lower end of the sides 14a,b are spaced apart a fixed amount by the footrests 20a,b and the bows42a,b, and the whole arrangement is triangulated to provide a rigid construction in the horizontal plane. Given the curvature of the bows 42a,b, and the dimensions of the wheelchair 10 generally, the chair 10 can be reversed over the standard toilet envelopel 35 sufficiently so that the toilet aperture 61 is disposed over the bowl 2 of the toilet. Indeed, to meet the requirements of the present invention, the centre of the toilet aperture 61 should be

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positionable over the centre of the bowl 2 of the toilet 1 of Figure 1.

[0044] From the assembled (erected) condition shown in Figure 2, the wheelchair 10 can be collapsed into a disassembled, stowed condition (see Figures 10 and 11) by undoing the latches 70 and separating the seat 12 from the sides 14a,b. Subsequently, or first, the latch pin

5 40 is withdrawn from the bores 32 in the ends of the footrest components 24a,b and from the link member 44.

[0045] Then, as shown in Figures 5 to 7, foot components 24a,b are pivoted about their axes 26. It should be noted that the foot component 24a,b is shaped at 24c to accommodate the ends 14c of the sides 14a,b. When folded to the position shown in the left of Figure 5, a spring

10 loaded locking pin 80, formed as part of the mounting component 22b, can be withdrawn from engagement with a bore 82 in the end 14c. On withdrawal of the locking pin 80, the footrest 20b, in its folded condition, can be pivoted about axis 84 to the position shown in Figure 7.

Here the footrest 20a,b adopts a position within boundary planes defined by the respective side 14a,b, as the case may be, and its corresponding main wheel 16, as can be seen most clearly 15 in Figure 12.

[0046] Referring now to Figure 8, the bows 42a,b are pivoted relative to the link member 44 about axes 48. At the same time, the bows are pivoted about their connection to the sides 14a,b about the axes 56. In so doing, the sides 14a,b approach one another until they reach the position shown in Figures 10 and 11, whereupon the whole wheelchair 10 can fit within a

20 package of approximately 500 mm square by 175 mm deep. The package can be fitted in a convenient carrying bag (not shown) for attachment to the rear of a normal day-use wheelchair.

[0047] As shown in Figure 2, the wheelchair 10 is of straightforward construction using metal or composite components that are either immune to the effects of wetting or are coated accordingly. The sides 14a in the erect condition shown in Figure 2 are parallel and essentially

25 vertical. However, there is nothing to prevent them being splayed outwardly to reduce the effect of side loads. The main wheels 16 are minimalist and potentially constructed from carbon fiber without tyre or handrail. A rim 16a may be applied comprising a rubber tape or the like to improve frictional contact with, potentially slippery, bathroom or shower room floors. Even in erected condition, the wheelchair 10 is compact so that there will not be difficulty in accessing 30 narrow shower doors. Moreover, easy access to all parts of the body may be had by a user when showering or using a toilet.

[0048] Although the seat 12 is described and shown herein as being completely detachable from the sides 14a,b, it need only be completely separable from at least one of the sides. Instead, it could be pivotally connected to either of the sides 14a,b. In this event, the link

35 member 44 may need to comprise overlapping components that separate when the latch pin 40 is removed. Alternatively the seat may be hinged on one side and pivot out over one of the

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wheels. In this event, the hinge connection between the seat and the respective side would be off set to distance the seat from the side so that it could lie adjacent and parallel to the main wheel connected to that side. In this way the link 44 can remain permanently connecting the bows. The latch pin 40 may also be permanently connected to one of the foot components 5 24a,b or the bows 42a,b in order to ensure that it does not become lost. Other methods of connection/attachment of the seat to the sides are evident to the skilled person and are not excluded.

[0049] Turning back to Figure 2 but also with reference to Figure 13 the wheelchair 10 also has a back support 90 and armrests 100. The backrest 90 is illustrated in its erected position. It

10 comprises two rods 92a,b pivoted to the seat 12 through hinge brackets 94 secured by plate part 95 to the seat, for example by screws 96 (see detail in Figure 14). The hinge bracket comprises a hinge about axis 98 which is parallel the seat 12 and optionally parallel the axis 18 of the wheels 16. The hinge axis is in front of the rods 92a,b. Hinge bracket 94 has socket part 97, hinged to the plate part 95, to receive the rods 92a,b. In the erected position of the back 15 support, socket part 97 abuts the seat 12 and prevents further pivoting of the hinge beyond a position in which the rods are substantially perpendicular the seat 12 or at such other inclined angle preferred for seat backrests. Between the rods 92a,b is supported a flexible sheet 99 of material that provides the back support. The back rest may be provided with means to lock in its erected position so a user can hook their inner elbow around it to gain leverage for movement 20 or support. Also, both the height and angle of the backrest are ideally adjustable. The height may be varied by providing a telescopic aspect (not shown) to the rods 92a,b so that their length may be adjusted. Similarly, a lockable knuckle joint (not shown) may be provided in the rods 92a,b near the socket part 97 so that the angle of the backrest is adjustable.

[0050] Turning to Figure 13, the backrest 90 is shown in its stowed position in which the rods 25 92a,b are pivoted so as to lie contiguous with the seat 12. Preferably, the seat is provided with grooves (not shown) in its top surface, either inside or outside the slots in its underside, to receive the rods 92a,b in the stowed position so that the thickness of the seat is not increased when stowed.

[0051] Returning again to Figure 2, armrests 100 are provided on each side of the wheelchair 30 100 and each comprises a curved rest component 102 and spoke components 104 that join at a hub 106 pivoted, about an axis 108 parallel the wheel axes 18, to the respective side 14a,b. Referring to Figure 13, it can be seen that, when the armrests 100 are pivoted to the stowed position shown, they occupy the space between the main wheel 16 and side 14a,b and, moreover, do not project, substantially, beyond the peripheral envelope defined by the 35 respective wheel and side (broadly speaking, the rectangle 111 outlined in Figure 11

surrounding the collapsed armchair). Accordingly, the arm rests 100 do not increase the

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volume occupied by the wheelchair in its stowed condition. Of course, they increase the weight of the wheelchair and therefore are constructed from a light material such as carbon fibre composite material. One side support could be lowered to allow access to that side of the wheelchair, then raised and the other side lowered for toileting washing access to the other 5 side.

[0052] Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of them mean "including but not limited to", and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the

10 context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0053] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be

15 understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the 20 details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0054] The reader's attention is directed to all papers and documents which are filed

25 concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

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Claims

1. A collapsible wheelchair for accessing a shower and toilet comprising:

a seat having a toilet aperture and defining a seat plane;

a footrest, pivotally mounted at one end to a lower front edge of each side, whereby each footrest is foldable relative to the side:

a) into a stowed condition in which it is substantially wholly within parallel boundary planes defined by an inner surface of the side and the main wheel mounted on said side; and b) into an erected condition in which its other end is releasably connected to the other end of the other footrest and is substantially perpendicular to said boundary planes and parallel said seat plane, which in said erected condition of the chair is arranged substantially perpendicular to said boundary planes;

a pair of bows interconnected by a link between them at one end of each bow and connected to a respective one of said sides at their other end, whereby:

in the erected condition, said link is fixed adjacent said connection between said other ends of the footrest to permit the bows and footrests to act as braces holding the sides in relative juxtaposition with the seat, the bows being so shaped that the chair may be reversed over a standard toilet bowl as hereinbefore defined through a rear opening of the chair defined by the seat and sides until the toilet aperture is substantially vertically aligned with the bowl of the toilet; and in the stowed position, said link permits folding of the bows so that said sides may be drawn into a side-by-side configuration after release of said seat from at least one side and after said foot rests have been folded into their stowed position,

wherein the sides, seat, footrests and bows provide a triangulated three dimensional structure in the erected condition of the wheelchair.

2. A wheelchair as claimed in claim 1, in which the seat is permanently pivotally connected to one side and pivots from the erected position to the stowed position to between the sides.

3. A wheelchair as claimed in claim 1 or 2, in which the sides and seat are each a single moulding of composite material comprising carbon fibre.

4. A wheelchair as claimed in claim 1, 2 or 3, further comprising a detachable toilet pan, means being provided for connection of the pan under the seat, whereby the wheelchair

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may be rendered as a commode.

5. A wheelchair as claimed in claim 4, in which said connection means comprises a horizontally disposed slot on each side, into which slot edges of the pan may be slid from behind or in front of the chair.

6. A wheelchair as claimed in any preceding claim, in which the connection of said other ends of the bows to the sides of the wheelchair are not further forward of the sides than the axis of the main wheels.

7. A wheelchair as claimed in any preceding claim, in which said bows are pivoted to the sides about side axes, each providing a single degree of freedom.

8. A wheelchair as claimed in any preceding claim, in which said bows are pivoted to the sides about sides axes that are a) substantially horizontal and b) substantially parallel to said sides.

9. A wheelchair as claimed in any preceding claim, in which said one ends of said bows are pivoted together about a link axis that is parallel said side axes.

10. A wheelchair as claimed in any preceding claim, in which said one ends of said bows are pivoted together about a link axis that provides a single degree of freedom.

11. A wheelchair as claimed in any preceding claim, in which the link between said bows may be a discrete component, being a link member, to which each bow end is pivoted.

12. A wheelchair as claimed in any preceding claim, in which the link member, and each footrest at each end, has a simple through-bore, all three of which through-bores may be aligned in the erect condition of the wheelchair and though which through-bores a latch pin may be inserted to lock all three components together.

13. A wheelchair as claimed in claim 12, in which the latch pin is of the type comprising a rod having a knob at one end and a protrudable key at the other end on release of a button on the knob, and the bores are of the same diameter as the rod, whereby the rod on full insertion of the latch pin in the through-bores and on release of the button engages the protrudable key to lock the rod in the through-bores and to lock the footrests and bows together.

14. A wheelchair as claimed in claim 13, in which the knob at its top end has is a central sprung loaded shaft, pressing which allows two balls forming said protrudable key at the other end of the shaft to retract into the body of the shaft allowing it to be withdrawn from the through bores in both footrests and the link.

15. A wheelchair as claimed in any preceding claim, in which said bows are arcs of a circle.

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16. A wheelchair as claimed in any preceding claim, in which said bows at their connection with the sides are substantially tangential with respect to said boundary planes and at their interconnection through said link are tangential a plane perpendicular to said boundary and seat planes.

17. A wheelchair as claimed in any preceding claim, in which each foot rest comprises a mounting component and a foot component, the two components being pivoted to one another about a foot axis, and wherein the mounting component is pivoted to the lower front edge of the respective side about a mounting axis substantially perpendicular to the boundary plane.

18. A wheelchair as claimed in claim 17, in which a spring-loaded locking pin is arranged between said mounting component and said side along an axis parallel said mounting axis and is adapted selectively to release and lock the mounting component and side.

19. A wheelchair as claimed in claim 17 or 18, in which each mounting component also mounts a caster wheel to support a minor amount of the weight of the chair and a person seated thereon when the chair is in an erected condition.

20. A wheelchair as claimed in any preceding claim, in which the seat comprises four blind slots on its underside, each adapted to receive one of a pair of noses formed along a top edge of each side, latches being provided to retain the seat in engagement with sides whereby movement of one with respect to the other is prevented:

a) in the boundary plane by the latch on the one hand and the noses engaging the blind bases of the slots; and b) in the seat plane, by the sides of the noses engaging the sides of the slots.

21. A wheelchair as claimed in any preceding claim, in which the seat comprises a ring forming the toilet aperture and four ears at four corners of the seat, each ear having one of said blind slots.

22. A wheelchair as claimed in claim 21, in which each ear comprises a pair of limbs, one being tangential a side of said aperture and the other being tangential a rear or front end of said aperture.

23. A wheelchair as claimed in any preceding claim further comprising a back support and side supports are provided to help support a disabled person seated on the wheelchair.

24. A wheelchair as claimed in claim 23, in which said armrests comprise a curved rest component connected to spoke components pivoted to the side between the side and the main wheel mounted on said side, whereby the armrest pivots between an erected position in which the rest component is above the level of the seat when the wheelchair is in its erected condition and a stowed position in which the arm rest is substantially within the peripheral footprint of the side and its main wheel.

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25. A wheelchair as claimed in claim 23 or 24, in which the back support comprises a pair of rods pivoted to the seat at the rear end of the seat, wherein the rods pivot between an erected position in which the rods are substantially perpendicular to the seat and a stowed position in which the rods are substantially coplanar with the seat, a flexible sheet being strung between the rods against which a user of the wheelchair may lean when the chair and backrest is in their erected condition.

26. A wheelchair as claimed in claim 25, in which a hinge bracket for each rod is attached to the seat providing a hinge axis positioned at a front side of the rod near its base, wherein the base of the rod abuts the bracket or seat in said erected position limiting rotation of the rod beyond said erected position.

27. A wheelchair as claimed in any of claims 23 to 26, in which the back support has means to lock in its erected position, whereby a user may hook their inner elbow around it to gain leverage for movement or support.

28. A wheelchair, substantially as hereinbefore described with reference to the accompanying drawings.