GB2393153A

GB2393153A - Wheel chair having a chassis of moulded construction

Info

Publication number: GB2393153A
Application number: GB0221492A
Authority: GB
Inventors: Michael Lovegrove
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-09-17
Filing date: 2002-09-17
Publication date: 2004-03-24
Also published as: GB0221492D0

Abstract

A wheel chair comprising a chassis 101 and a seat 102 for a user of the chair wherein the chassis 101 is of moulded construction produced by the use of a pre-formed mould. The chassis 101 can be of monocoque construction and can be made of aluminium alloy, a fibre-reinforced moulding or a wood laminated moulding. The construction of the wheel chair can include suspension arms 111 which carry wheels 113, suspension units (116, fig 2) can be interchanged so as to tailor the use of the chair to a specific type of usage. The chair can also comprise braking means and/or a motor unit used to drive the chair.

Description

WHEEL CHAIR

The present invention relates to wheel chairs for use by individuals suffering from disabilities.

Existing wheel chairs consist of a fabricated tubular chassis to which is attached a seat for a user of the wheel chair. The chassis has two front wheels, and two rear wheels. Even with the use of jigs, the manufacture of the tubular chassis is a relatively complicated operation which iS time o consuming and therefore relatively expensive, particularly as each joint in the chassis needs to be inspected for soundness. Also, despite electro-

plating of the chassis, again an expensive operation because of the preparation and finishing involved, the appearance of existing wheel chairs remains utilitarian.

It is an object of the present invention to provide an improved wheel chair with an enhanced appearance compared with existing wheel chairs.

According to the present invention, there is provided a wheel chair to comprising a chassis 'and a seat for a user of the wheel chair, wherein the chassis is of moulded construction.

The term "moulded construction" is used to indicate that the chassis is produced by the use of a pre-formed mould. The term encompasses 25 conventional casting techniques, fabrication by the laying-up of composite materials and the pressing of sheet materials.

The chassis of the wheel chair of the present invention, nosy also be said to be of monocogue construction in bleat, although for convenience it inky be

made of more than one component, when assembled, operational loads are borne by the chassis as a whole, rather than a spatially distributed network of tubular sections, some of which in use are relatively highly stressed and some of which are relatively lowly stressed.

The use of moulding techniques to produce the chassis enables much more aesthetic shapes to be produced than is possible with conventional tubular wheel chair chassis.

Preferably, the seat portion is an integral part of the chassis and the chassis includes resilient suspension units for at least the main wheels of the wheel chair. A suitable form of suspension unit is a swinging arm controlled by combined spring/damper units, similar in principle to those used on motorcycles. Alternatively, a form of McPherson strut could be used.

Preferably, the chassis members are cast in aluminium alloy by conventional metallurgical techniques. Alternatively, the chassis members may be made of fibre-reinforced plastics materials, again using conventional techniques. Other materials which can be used for the chassis are hot or to cold-moulded wooden laminates, or metal pressings.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: s Figure I is a schematic side view of a wheel chair embodying the invention, Figure 2 is a schematic side view of the chassis of the wheel chair shown in Figure 1,

[figure 3 illustrales In more detail the flitting of the mountain bike suspension unit to the wheel chair of' figure I figure 4 is a plan view of the chassis ofthe wheel chair of' figure I figure shows the m,dtied suspension arm for the electrically powered version of' the wheel chum Kel'nng to figures I & a, a hand propelled wheel chair 100 embodying the invention, consists of a chassis I U I made of cast aluminium Riley. 'I he chassis IV I of the wheel chair 1(1(} has a seat portion 1(] and two forwardly projecting sloping side members. 1(3, ot'which only one ot'course is visible in the drawing. The lower end of each side member lo terminates in a boss l(t4 in which a wheel 1)S is mounted pivotally, The mounting 1)6 for the wheel llt5 Is adapted to, trail so as to provide a self2centering action while permtlng the wheel chair l(N) to he steered by the user of the wheel chair. 'I'he middle section of the side members lft] are conJomed by a brace 1(17 as shown In Figure 4.

I'he seat portion 101 may be a moulded part of' the chassis 1(1 of the wheel chair IW, or it may comprise back and side portions with attachment points for a separate canvas seat.

I'he preferred embodiment would be a separately moulded seat permanently affixed to chassis 1(1 and summoned at its front try brace 1()1. The back ofthe seat portion 1()] is raked and curved to provide proper support and comfort for the back of the user ova wheel cham I'wo mounting brackets, 1 (is and 1(19 are attached to the underside of each side member I (J. of the chassis 10 I. I he mounting bracket 1(18 has a hole formed in it to provide a pivot point 10r an aluminum alloy suspension arm I I 1. The suspension awn I I I has two threaded holes I I for boss I 19 At its centre to provide alternative attachment points for a wheel 1 13 of' the wheel chair 11(). 'Ihe suspension arrnI I I also includes I'ghtening fables 114. Ihe suspension arml I I Is mounted m the mounting bracket 1(8 via a bearing assembly which may be of any convenient type which provides for both rotary motion and resistance to lateral thrust.

I'he mounting bracket 11!} has fl threaded hole to accept bolt 1 15 that in turn attaches a mountain hike suspension unit I I to bracket l(J. The other end otsu,rpension unit 110 is attached to suspension ann I I I at bracket 117 by pin I IS, 1 he combination of two wheel positions I I on the suspension arm I I I and the bulit In spring tension ubutment on the mounting hike suspension units 116 and dtlerent types ol'spnugs commercial available enables a wheel chair ride height and suspension characteristics to be tailored to the requirements ot'a particular user of' the wheel chair and coyer the range trom conventional use to sporting use.

Although it Is not Illustrated In the drawmg,there may be incorporated a hand-brake which beers on the lyre of one or troth ot the wheels 1 18 of' the chair loo.

As Illustrated, the primary wheels 113 of the wheel chair IW are operated in the conventional way by a push-nm 121, but f'so desired each of the wheels 1 13, may Include A geared hub such as that described In our patent (;H:2322835. Also the wheel chair may be adapted to be amen by power units in the form ot'pmprietary wheel chair electric motors on modified suspension armsl;2 as seen in figure 5 T'he motors 123 are mounted at pointl 14 on suspension arm 125 and bolts passed through hi les i 2f into the motor gearbox location holes. The dime wheels 1 13 may then he fitted to the motors as the axles may tit in the drive shaft of' the elestrtc motors.

So with the addition of wheel chair batteries and a readily available hand controller a powered version of the wheel chair Is created.

Another possible moditcation is to include in the back of the seat portion 1(1:2 of the chassis lt)l ofthe wheel chair 10 sockets adapted to receive back rest that could include push handles for the wheel chair IW.

Claims

(CLAIMS

1. /\ wheel chair comprising a chassis arid a seat for a user of the wheel chair wlereh, the chassis is of mouldcd, as hereinbelire defined, constructio',.

2. A wheel chair according to Claim I wherein the chassis includes two

pivotally mou',tel suspensions arms, each aria Beirut adapted lo receive a primary wheel of the wheel chair.

3. A wheel chair acc<,rJi'' lo C'lai',, 2 whcrci', Ihc mounli'gs liar Ihc suspc'sio', amps arc adapicd to provide a plurality of mou',ti'' points for the suspcnsio', arms

4. A wheel chair according to Claim 2 or Clahu 3 wherein the suspension alms are adapted to provide a plurality of attachment points for the axles ol the primary wheels of the wheel chair.

5. A wheel chair according to any of Clahns 2 to 4 wherein the motion of the suspension arms is,co'trolled by resilient suspension units.

6. A wheel chair according to Claim 5 wherein each suspension unit comprises a spring and an associated damper.

7. A wheel chair according to Claim 5 or Claim 6 where)'' there is included means for varying the characteristics of tlc resilient suspension units.

8. A wheel chair according lo any preceding claim wherein Ihc chassis is of unitary construclio', arid firms a single load-beari'g structure

b

9. A wheel chair according to any preceding claim wherein the chassis is cast from an aluninium alloy.

10. A wheel chair according lo any of (plaints I to 8 wherein the chassis is made of a fibre-reinforced composite material.

I 1. A wheel chair according to any Claims I to 8 wherein the chassis is made frown a moulcled wood laminate naterial.

12. A wheel chair according to any preceding claims wherein the chassis is adapted to receive a power unit arranged to drive the primary wheels of the wheelchair.

13. A wheel chair according to any preceding claims, wherein there is included a brake adapted to be operated by a user of (he wheel chair.

14. A wleel chair substantially as hereinbeFore described and with reference to the accompanying drawings.