GB2319995A - Vehicle conversion for the transport of wheelchairs - Google Patents

Abstract

A vehicle of the kind having a live rear axle 11 and a Panhard rod 20 is converted for the transport of wheelchairs, the method including providing new Panhard rod mountings on the vehicle 31 and the axle 33 such that the Panhard rod is positioned below its original position and lowering a portion 24 of the vehicle floor from the rear entry point of the vehicle over the rear axle. The lowered portion of the floor may be flat or sloped to facilitate loading of a wheelchair. Lateral reinforcement of the vehicle structure may be provided in the form of a plate or a space frame.

Description

Vehicle Conversion This invention relates to the transport of wheel chairs and in particular to the conversion of standard motor vehicles for use in the transport of disabled people in situ in wheel chairs.

Disabled people who do not have full use of their legs, or have lost their legs, use wheel chairs to maintain their personal mobility. Naturally wheel chair users, like most people, require access to motor vehicles for long distance transport, especially in view of the lack of facilities for wheel chair occupants on public transport. However, wheel chairs are bulky objects not readily accommodated in vehicles and, although the wheel chair may typically be folded for stowage, this requires the occupant to be carried out of the wheel chair and onto a seat of the vehicle in order to allow the occupant to enter. This can be a time consuming and difficult process, which is a frequent cause of back injury to carers for the disabled. It is desirable therefore to allow the wheel chair occupant to remain seated in the wheel chair inside the vehicle.

To achieve this object, a known method is to adapt a standard estate motorcar or van by extending the roof of the vehicle upwards to provide the extra headroom required by the occupant of a wheelchair, and providing ramps so that the wheel chair can be entered into the back of the vehicle. Needless to say this is an expensive process requiring extensive modification of the superstructure of the vehicle and re-positioning or addition of windows.

Another disadvantage is that the wheel chair occupant sits at a height significantly higher than the other occupants of the vehicle. This constitutes a social impediment to the wheel chair occupant in that communication both visually and orally with other vehicle occupants is restricted. In addition, the wheel chair occupant's line of sight outside the vehicle is significantly higher than the usual vehicle occupant.

This has the effect that many sights and interactions with the outside world are obscured or altered.

Other disadvantages include the length of ramp necessary to produce a reasonable incline for entry at the floor level of the vehicle and the potential danger of the wheel chair tipping from a high ramp and the distress thereby caused to the occupant during loading.

These latter problems have been addressed by providing lift mechanisms, but these are in themselves bulky and expensive articles.

It is an object of the present invention to overcome or reduce the aforementioned problems.

According to one aspect of the present invention there is provided a method of converting a motor-vehicle for wheel chair entry comprising lowering a portion of the vehicle floor, which portion extends from the rear entry point of said vehicle and over the rear axle of the vehicle.

By lowering the floor, the conversion process does not have to involve an extension of the roof line. In addition, the ramp length for wheel chair entry is reduced in view of the decreased height to be climbed, which reduction improves ease of handling and use of the ramp.

According another aspect of the present invention there is provided a method of converting a motor-vehicle of the type having a live rear axle and a panhard rod which inhibits lateral body displacement relative to the rear axle during cornering, which method comprises: - forming new panhard rod mounting points on the chassis and the rear axle such that the panhard rod is positioned substantially parallel and below its original position, and - lowering the vehicle floor towards and/or into the area previously occupied by an upper end of the panhard rod.

The vehicle floor may be translated downwards uniformly, or may be sloped to provide an incline downwards to wards the rear of the vehicle. This facilitates the loading of wheel chairs into the vehicle.

The upper end of the panhard rod is preferably mounted on a lower end or depending extension of the chassis (or monocoque as appropriate). The depending extension may comprise a strut which extends from the original site of the panhard mounting, thereby ensuring a strong anchorage for the strut.

Ideally the panhard rod is mounted absolutely parallel to its initial position so that the suspension geometry is unaltered. However, in other embodiments there may be variations in the orientation, the variations permitting of adequate suspension behaviour.

The lower end of the panhard rod may be mounted on a side of the axle casing, or an extension of the axle casing, at a lower position than the original position. A depending member may be provided on the axle to permit of lower extension of the rod.

Where the axle connection has been moved from an upper surface of the axle, a corresponding forward or rearward adjustment of the upper mounting may have to be made to maintain the optimum configuration of the rod.

A lateral reinforcer, such as a stabiliser bar or other structural reinforcement member may, initially, be present on the vehicle to provide lateral rigidity to the rear of the chassis by reinforcement between the attachment points of the rear suspension to the chassis.

Where this would prevent lowering of the floor, in another aspect of the invention the method may further comprise discarding the stabiliser bar/ and reinforcing the chassis and/or floor to compensate for the loss of rigidity.

The reinforcement may be effected by providing a depending structure at each side of the vehicle in-board of the rear suspension and combined with a lateral structure joining lower ends of the depending structure.

An upper surface of the lateral structure may form or be provided with a floor surface. The lateral structure may be horizontal, but in a preferred arrangement the depth of the structure may increase towards the vehicle rear to form an incline.

The depending and/or lateral structures may each be formed from solid or composite plate material. However, in a preferred embodiment the depending/lateral structure comprises a space frame structure. The space frame structure may comprise a plurality of laterally extending drop hanger bars, each longitudinally spaced from the next on the vehicle.

Each hanger bar comprises an elongate member provided with upstanding end portions. The distal ends of these end portions are attached to the vehicle chassis so that the elongate member extends laterally and depending from the chassis structure. Attachment may be by any structural connection method, but in a preferred arrangement is by welding. The drop hanger bars are preferably fabricated from box-section tubing and may be formed of mild steel material. The length of the end portions may be varied from hanger to hanger so that an incline is formed towards the rear of the vehicle.

To provide added reinforcement, and longitudinal constraint of the drop hanger bars, one or more H-frames may be laterally disposed between adjacent elongate members of the drop hanger structure to form a complete structure of longitudinal and transverse members.

The H-frames are preferably each fabricated from boxsection tubing, for example in mild steel, and joined by welding or another suitable structural connection.

The floor of the vehicle may be lowered in the conversion method to be juxtaposed the elongate members and associated space frame. The floor may be spaced therefrom slightly or may abut the floor to provided reinforcement thereof.

The reinforcement structure discussed may be constructed of box section material, however, any beam section which imparts sufficient strength and rigidity against bending and buckling from lateral stresses induced by cornering and vehicle loading may be used. Examples are H section, L-section or tubular section beams.

Suitable materials for the space frame structure include metals such as steel or light alloys. Alternatively composite materials may be used.

Following is a description by way of example and with reference to the figures of the drawings of a method of putting the present invention into effect.

In the drawings: Figure 1 is a schematic view from the rear, and partially in section, of the rear suspension of a vehicle before conversion.

Figure 2 is the same view as figure 1 after conversion by the method of the present invention.

The lower portion of a Peugeot Expert, Fiat Scudo, Citroen Despatch (all trade names) type light van is shown schematically at figure 1. The vehicle body 10 is carried by suspension coils (not shown) connected to the axle casing 11. The axle casing 11 is an elongate tubular member which carries an axle . The axle extends between two rear wheels (13,14) of the vehicle, permitting rotation thereof and structural connection thereof. A lower end 15 of a panhard rod 20 is attached to the axle by means of a pivoting joint 16 which permits of deflection of the rod in a vertical plane. The rod extends diagonally upwards in the vertical plane where an upper end 17 is attached to the underside 30 of the vehicle chassis structure by means of another pivoting joint 18. Thus the rod 20 allows vertical displacement of the axle whilst preventing lateral displacement relative to the chassis. Furthermore, in combination with the lateral constraint of the coil springs (not shown), the panhard rod has the effect of stiffening the suspension compliance progressively to inhibit body sway during cornering. A stabiliser bar 21 is an elongate member which extends laterally between the two regions of high load where the coil springs are attached to the vehicle chassis/monocoque. This provides lateral rigidity to the rear of the vehicle. The bar 21 is attached to the chassis between depending U-brackets 22,23.

Figure 2 shows the same structure after conversion. The floor 24 of the vehicle has been lowered to form a lateral recessed portion 25. The stabiliser bar 21 has been replaced by a plurality of drop hanger bars 26 (one shown). The drop hanger bars are elongate box-section mild steel members provided with two upstanding end portions 27,28 respectively. The end portions are each connected to a side of the chassis at the same lateral separation as the original site of the stabiliser bar brackets. A depending rigid bracket 30 extends from the original site of the panhard rod chassis connection. A lower end 31 of the bracket provides a pivoted connection for the upper end 17 of the panhard rod. The lower end 15 of the panhard rod is attached to the axle casing at a rear side thereof at a pivoting joint 33, having been moved from the top of the casing. Thus the panhard rod is substantially lower than before, and clears the under edge of the vehicle floor.

By the method of the present invention, a vehicle having a live rear axle configuration can be converted for wheel chair use by lowering of the floor notwithstanding the fact that the normal suspension and structural arrangement in the region of the rear wheels would prevent such a conversion. By providing a depending panhard rod connection, rather than completely reconfiguring the vehicle structure and suspension geometry, a simple and elegant conversion may be made, with a corresponding minimization of costs.

Claims (19)

1. A method of converting a motor-vehicle for wheel chair entry, which vehicle is of a type having a live rear axle and a panhard rod which inhibits lateral vehicle body displacement relative to the rear axle during cornering, which method comprises: -forming new panhard rod mounting points on the chassis or monocoque and the rear axle such that the panhard rod is positioned below its original position, and -lowering a portion of the vehicle floor, which portion extends from the rear entry point of said vehicle and over the rear axle of the vehicle, and which portion is lowered towards and/or into the space originally occupied by an upper end of the panhard rod.

2. A method as claimed in claim 1 wherein the lowered portion of the vehicle floor is translated downwards uniformly.

3. A method as claimed in claim 1 wherein the lowered portion of the vehicle floor is sloped to provide an incline downwards towards the rear of the vehicle thereby to facilitate the loading of a wheel chair into the vehicle.

4. A method as claimed in any of the preceding claims and comprising mounting an upper end of the panhard rod on a lower end or depending extension of the vehicle chassis or vehicle monocoque, as appropriate.

5. A method as claimed in claim 4 wherein said depending extension comprises a strut which extends from the original site of the panhard mounting thereby ensuring a strong anchorage for the strut.

6. A method as claimed in any of the preceding claims wherein the panhard rod is mounted substantially parallel to its oriainal position so that the substantially suspension geometry islunaltered.

7. A method as claimed in any of the preceding claims wherein a lower end of the panhard rod is mounted on one side of an axle casing or an extension of the axle casing and at a lower position than the original position.

8. A method as claimed in claim 7 wherein the axle extension comprises a depending member provided on the axle casing in order to permit of positioning of the panhard rod.

9. A method as claimed in any preceding claim wherein said vehicle comprises a lateral reinforcer, such as a stabiliser bar or other structural reinforcement member initially present on the vehicle to provide lateral rigidity to the rear of the chassis by reinforcement between the attachment points of the rear suspension to the chassis, which method further comprises discarding the structural reinforcement member and reinforcing the chassis and/or floor to compensate for the loss of rigidity.

10. A method as claimed in claim 9 wherein the reinforcement is effected by providing a depending structure at each side of the vehicle in-board of the rear suspension and combined with a lateral structure joining lower ends of the depending structure.

11. A method as claimed in claim 10 wherein an upper surface of the lateral structure forms or is provided with a floor surface.

12. A method as claimed in claim 11 wherein the depth of the lateral structure increases towards the rear of the vehicle thereby to form an incline.

13. A method as claimed in any of claims 10 to 12 wherein the depending and/or lateral structures are each formed from solid or composite plate material.

14. A method as claimed in any one of claims 10 to 12 wherein the depending and/or lateral structure comprises a space frame structure.

15. A method as claimed in claim 14 wherein the space frame structure comprises a plurality of laterally extending drop hanger bars, each longitudinally spaced from the next on the vehicle.

16. A method as claimed in claim 15 wherein the length of end portions of each drop hanger bar is varied from hanger to hanger so that an incline of hanger bars is formed towards the rear of the vehicle.

17. A method as claimed in claim 15 or claim 16 wherein added reinforcement and longitudinal constraint of the drop hanger bars is provided by one or more H frames laterally disposed between adjacent elongate members of the drop hanger structure thereby to form a complete structure of longitudinal and transverse members.

18. A method as claimed in any one of claims 14 to 17 wherein the floor portion of the vehicle is lowered such that it is juxtaposed the elongate members and associated space frame.

19. A motor-vehicle converted for wheel chair entry by a method as claimed in any of the preceding claims.