GB2314048A - Wheelchairs - Google Patents

Abstract

In a wheelchair, support for the body of the user is provided by a module (20), moulded from a plastics material as a hollow box-like unit. The module (20) can constitute an integral seat (22) and back (24) of the chair. In another embodiment the seat and back are separate modules. The module can alternatively have a tubular frame providing back support, with said frame being attachable and detachable from a seat module, whereby the frame can be folded down. Attached to the hollow box-like unit (20) are integrally moulded handles (26) for steering the chair and arm rests (28) which have a horizontal stiffening tube extending transversely of the chair. The module or modules are mounted on a subframe or chassis.

Description

WHEELCHAIRS This invention relates to wheelchairs, and is particularly concerned with wheelchairs which are based upon the use of a hollow modular support for the user, mounted on a chassis or sub-frame.

Many different designs of wheelchair are known.

Many are very complex. It is an object of the invention to provide a wheelchair which is simple in its construction, which is easy to clean, disinfect and maintain, and which can be manufactured relatively inexpensively.

The present invention is based on the concept of providing a support module or modules for the user, each module being a hollow, preferably moulded, boxlike unit. Each module is preferably a moulded plastics unit; rotational moulding is the preferred manufacturing technique. Preferably, one module constitutes an integral seat and back of the chair, although these parts can be separate.

The module or modules is/are mounted on a subframe or chassis which may be of stainless steel and/or aluminium and which can incorporate wheels, castors, brake mechanism, etc.

In a preferred embodiment of wheelchair the seat/back module has integrally moulded handles for steering the chair.

For a wheelchair which has arm rests, these are preferably designed to latch into a receiving mechanism integral with or attached to the chair back. At the forward end, the arm rests preferably each include a horizontal tube extending transversely of.the^ tair, and preferably within the volume of the seat, with to two tubes being slidable one within the other. In ffbi's way, after an arm rest has been unlaturhe at:')he rearward end, it can be removed from the chaitr being withdrawn sideways.

In order that the invention may be more fully understood, a number of embodiments of wheelchair in accordance with the invention will now be described by way of example and with reference to the accompanying drawings, in which: Fig. 1 is a schematic view of a first embodiment; Fig. 1A is a detail view showing part of the chair back of Fig. 1; Fig. 2 shows the chair of Fig. 1, partly broken away to show the arm rest structure; Fig. 3 shows the chair of Fig. 1 with one arm rest unlatched; Fig. 4 is an exploded view of the chair of Fig. 1 showing the modular seat/back and the chassis; Fig. 5 shows a second embodiment of chair with a low back support; and, Fig. 6 shows a third embodiment of chair with a tubular removable back rest.

Referring first to Figs. 1 to 4 these show a wheelchair which comprises a sub-frame or chassis 10 which is fitted with a pair of wheels 12 and a pair of front castors 14. The chassis 10 carries at the front a pair of footrests 16 which can pivot individually to the side. As shown most clearly in Fig. 4, the chassis is also fitted with a brake mechanism 18 at each side.

On the chassis is mounted a user-support module 20. This is a moulded plastics box-like structure which in this embodiment constitutes both a seat 22 and a backrest 24. It has the shape of a generally Lshaped box. It is preferably rotationally moulded, although it could alternatively be blow moulded. The walls of the module 20 are preferably of the order of 3 mm thickness for a module made of high density polyethylene. However, other materials could be used.

The backrest portion 24 of the module 20, as shown in Fig. 1A, has triangular-shaped indents. These give the structure added strength, to withstand the twisting forces which occur when the chair is manoeuvred with a person seated in it.

The wheelchair has a pair of arms 28. Each arm comprises an arm-rest 30, a pin 32 at the rearward end, a generally downwardly extending support 34, and a horizontally extending tube which extends into the body of the seat 22. As shown most clearly in Fig. 2, the two horizontal tubes 35, 36 slide one within the other.

This gives added strength and stiffness to the structure. The outer tube 36 can be moulded integrally with the seat, with the inner tube 35 then being slidable into it. Fig. 3 shows how the pins 32 latch into catches 38 on the sides of the backrest. The plastics catch 38 is pushed back in the direction of arrow X to release the pin, so that the arm can then be pivoted in the direction of arrow A, or removed completely by sliding it sideways.

Fig. 4 shows the support module 20 separated from the chassis 10. The sub-frame or chassis 10, or part of it, could alternatively be made part of the module moulding. It could also be made of plastics material instead of metal. Also the brake mechanism 18 could be mounted on the support module 20 instead of on the subframe.

Fig. 5 shows a modified chair with only a low back support 24.

Fig. 6 shows a chair where the backrest 40 is a tubular frame which is attachable to and detachable from the module 20 using locating pins 42. The frame can be folded down. In this embodiment there is a fixed footrest 44 at the front of the chair and mounted on the sub-frame.

The principles of the present invention are applicable to wheelchairs of many different types.

These include transit chairs, sports chairs and childrens' chairs.

Claims (11)

1. A wheelchair in which support for the body of the user is provided by a module or modules, wherein the or each module is a hollow box-like unit.

2. A wheelchair according to claim 1, in which the or each support module is moulded from plastics material.

3. A wheelchair according to claim 1 or 2, in which the or each support module is a rotationally moulded unit.

4. A wheelchair according to any preceding claim, in which one module constitutes an integral seat and back of the chair.

5. A wheelchair according to any preceding claim, in which the module or modules is/are mounted on a subframe or chassis of stainless steel and/or aluminium.

6. A wheelchair according to any preceding claim, in which the module or one of the modules has integrally moulded handles for steering the chair.

7. A wheelchair according to any preceding claim, which includes arm rests which are arranged to latch into a receiving mechanism integral with or attached to the chair back, and wherein, at the forward end of each arm rest, there is provided a horizontal stiffening tube extending transversely of the chair, with the respective tubes being slidable one within the other.

8. A wheelchair according to any preceding claim, in which the horizontal stiffening tubes extend transversely within the volume of the seat.

9. A wheelchair according to any preceding claim, in which at the front there is a pair of footrests which can either pivot individually to the side or are fixed in place.

10. A wheelchair according to any of claims 1 to 3, which includes a tubular frame providing back support, said frame being attachable and detachable from a seat module using a locking device, whereby the frame can be folded down.

11. A wheelchair substantially as hereinbefore described with reference to Figs.1 to 4, Fig.5 or Fig.6 of the accompanying drawings.