GB2260298A - Transportation apparatus - Google Patents

Abstract

A transportation apparatus such as a wheelchair (1) comprises a frame (2) having at least three balls (3) mounted therein for engaging a surface on which the apparatus is to travel. Each ball is mounted in the frame by way of a pair of planet assemblies (14), the planet assemblies each comprising a plurality of rotatable members mounted in a support, the support being secured to the frame (2) and the rotatable members engaging with the surface of the respective ball (3). The two planet assemblies (14) are arranged in substantially parallel planes on opposite sides of the centre of the respective ball (3). <IMAGE>

Description

TRANSPORTATION APPARATUS The present invention relates to a transportation apparatus such as may be incorporated, for example, into a wheelchair or the like.

Conventional wheelchairs comprise a frame provided with a pair of wheels of relatively large diameter positioned towards the rear thereof and a pair of wheels of relatively small diameter positioned towards the front thereof. The forwardly positioned pair of wheels are generally pivotable about a vertical axis in order to permit the wheelchair to be steered. These conventional wheelchairs have the disadvantage that they are difficult to manoeuvre, especially in confined spaces. They also have the disadvantage that they are specifically designed for use solely as wheelchairs and are not readily adaptable for alternative, related uses.

It is an object of the present invention to provide a transportation apparatus, such as may be incorporated, for example, into a wheelchair or the like, which apparatus is readily manoeuvrable, especially in confined spaces.

According to one aspect of the present invention there is provided a transportation apparatus comprising: a frame; at least three balls mounted in the frame for engaging a surface on which the apparatus is to travel; and a pair of planet assemblies for mounting each ball in the frame, the planet assemblies each comprising a plurality of rotatable members mounted in a support, the support being secured to the frame and the rotatable members engaging with the surface of the respective ball, wherein the two planet assemblies are arranged in substantially parallel planes on opposite sides of the centre of the respective ball.

The planet assemblies may be arranged substantially horizontally or substantially vertically.

The frame may comprise upper and lower sub-frames extending around the balls. Four balls may be provided. The balls may be made of PVC plastics material. The rotatable members may comprise spheres or rollers. The rotatable members may be made of nylon plastics material.

The transportation apparatus may include floor jacks for inhibiting undesired movement of the apparatus.

Alternatively, the transportation apparatus may include a generally wedge-shaped brake member for insertion between adjacent balls.

The transportation apparatus may include means for driving the apparatus. The driving means may comprise a plurality of continuously rotatable rollers which are engageable with one or more of the balls.

According to another aspect of the present invention there is provided a wheelchair incorporating a transportation apparatus as hereinbefore defined.

For a better understanding of the present invention and to show more clearly how it may be carried into effect reference will now be made, by way of example, to the accompanying drawings in which: Figure 1 is a diagrammatic side elevational view of one embodiment of a transportation apparatus according to the present invention in the form of a wheelchair; Figure 2 is a diagrammatic front elevational view of the wheelchair shown in Figure 1; Figure 3 is a view from below of the wheelchair shown in Figures 1 and 2; Figure 4 is a diagrammatic front elevational view of another embodiment of a transportation apparatus according to the present invention in the form of a wheelchair; and Figure 5 is a view from below of the wheelchair shown in Figure 4.

Figures 1 to 3 show a wheelchair 1 comprising a tubular metal frame 2 mounted on four freely rotatable balls 3 which in use engage a surface such as a floor on which the wheelchair is to travel. The frame 2 comprises three essentially identical sub-frames 4, 5, 6 arranged substantially horizontally in a spaced arrangement. The lowest sub-frame 4 comprises a substantially square frame with two support bars 7 extending from the front to the rear of the frame. The middle sub-frame 5 is identical to the lowest sub-frame 4, while the uppermost sub-frame 6 does not incorporate the support bars 7. The corners of the sub-frames 4, 5, 6 are rounded for safety reasons. The sub-frames 4, 5, 6 are supported rigidly in their spaced apart relationship as a result of being secured, as by welding, to a pair of side frames 8, 9 which are generally in the shape of an inverted-U.Armrests 10 are mounted on the upper part of each side frame 8, 9 and a seat cushion 15 is mounted on the uppermost sub-frame 6. A back supporting cushion 11 is mounted on a rear frame 12 which is rigidly secured to the side frames 8, 9, for example by welding. A handle 13 for pushing the wheelchair 1 is secured to the rear frame 12, for example by welding.

Each ball 3 is mounted in two circular planet assemblies 14 provided above and below the centre of the respective ball 3. The planet assemblies 14 are positioned substantially mid-way between the elevation of the centre of the ball and the top and bottom of the ball. The elevation of the planet assemblies is not critical, but the lower assembly should be located such that it does not inhibit the wheelchair 1 mounting small obstacles in its path. For a wheelchair 1 having a substantially square cross section with the dimension of each side being of the order of 650 mm, the balls 3 may be made, for example, of a PVC plastics material having a diameter of the order of 240 mm and a thickness of 5 mm. Generally, the diameter of the balls 3 should be in the range from 10 to 50 per cent of the dimension of the sub-frames 4, 5.The size of the balls is not critical, but requires to be such as to reduce rolling resistance to a reasonable level, for example to permit the wheelchair 1 to mount small obstacles such as carpet edges or to move into and out of lifts. Each planet assembly 14 comprises a cage in which there is arranged a plurality of spheres or rollers (not shown) supporting the ball 3 in known manner. In the case of spheres, the spheres may be made, for example, of nylon plastics material and may have a diameter of some 25 to 38 mm.

The wheelchair can be readily manoeuvred by an occupant or by a person pushing from behind. Where it is being manoeuvred by an occupant within a building or the like, for example in a domestic environment, it can be moved or turned simply by pushing against a wall or other object.

Clearly many features of the wheelchair shown in the figures can be modified.

For example, it is possible to arrange for all or part of the upper region of the tubular frame to be removable, for example down to and including the uppermost sub-frame 6.

This would leave a basic transportation apparatus which could be used for other purposes, for example two such basic transportation apparatus could be combined with a connecting assembly to form a wheeled stretcher. The tubular frame may be provided with means for attaching medical equipment such as drip feeds, and a tray or other apparatus may be arranged beneath the seat cushion 15.

It is not essential to have four balls 3. The number of balls can be reduced to three or increased to five or more as required for a given application.

In order to inhibit undesired movement of the wheelchair, for example to prevent it running away down a slope, the wheelchair may be fitted with floor jacks which incorporate friction feet biased towards the floor on which the wheelchair is running and which require to be raised in order for the wheel chair to be able to move, for example by way of a lever mechanism built into the handle 13 or into one of the side frames 8, 9. Alternatively, the wheelchair may be provided with brakes, for example generally in the form of wedges which engage between adjacent balls 3.

Additionally, the wheelchair may be powered, for example by way of a plurality of hard rubber rollers vulcanised onto continuously rotatable shafts. The rollers may be moved to engage or disengage the balls by switch means, such as finger operated switches.

The wheelchair 1 shown in Figures 4 and 5 is a modification of the chair shown in Figures 1 to 3 and the same reference numerals are used to denote the same or similar parts. The wheelchair comprises a tubular metal frame 2 mounted on four freely rotatable balls 3 which in use engage a surface such as a floor on which the wheelchair is to travel. The frame 2 comprises three essentially identical sub-frames 4, 5, 6 arranged substantially horizontally in a spaced arrangement. Secured, for example by welding or by means of an adjustable screw arrangement, to the two lower subframes 4 and 5 are three upright plates 16 which extend substantially from the front of the wheelchair to the back thereof. However, the plates could be arranged from sideto-side if desired. The corners of the sub-frames 4, 5, 6 are rounded for safety reasons.The sub-frames 4, 5, 6 are supported rigidly in their spaced apart relationship as a result of being secured, as by welding, to a pair of side frames 8, 9 which are generally in the shape of an inverted-U. Armrests 10 are mounted on the upper part of each side frame 8, 9 and a seat cushion 15 is mounted on the uppermost sub-frame 6. A back supporting cushion 11 is mounted on a rear frame 12 which is rigidly secured to the side frames 8, 9, for example by welding. A handle 13 for pushing the wheelchair 1 is secured to the rear frame 12, for example by welding.

Each ball 3 is mounted in two circular planet assemblies 14 provided laterally, one at each side, of the respective ball 3. The planet assemblies 14 are secured, for example by bolts (not shown) to the upright plates 16. The elevation of the planet assemblies is not critical, but the assemblies should be located such that they do not inhibit the wheelchair 1 mounting small obstacles in its path. For a wheelchair 1 having a substantially square cross section with the dimension of each side being of the order of 650 mm, the balls 3 may be made, for example, of a PVC plastics material having a diameter of the order of 240 mm and a thickness of 5 mm. Generally, the diameter of the balls 3 should be in the range from 10 to 50 per cent of the dimension of the sub-frames 4, 5. The size of the balls is not critical, but requires to be such as to reduce rolling resistance to a reasonable level, for example to permit the wheelchair 1 to mount small obstacles such as carpet edges or to move into and out of lifts. Each planet assembly 14 comprises a cage in which there is arranged a plurality of spheres or rollers (not shown) supporting the ball 3 in known manner. In the case of spheres, the spheres may be made, for example, of nylon plastics material and may have a diameter of some 25 to 38 mm.

As shown in Figure 5, the wheelchair 1 may be braked by means of generally wedge-shaped members which are positioned between adjacent balls 3 and are able to be inserted between the balls to prevent rotation thereof.

Claims (14)

1. A transportation apparatus comprising: a frame; at least three balls mounted in the frame for engaging a surface on which the apparatus is to travel; and a pair of planet assemblies for mounting each ball in the frame, the planet assemblies each comprising a plurality of rotatable members mounted in a support, the support being secured to the frame and the rotatable members engaging with the surface of the respective ball, wherein the two planet assemblies are arranged in substantially parallel planes on opposite sides of the centre of the respective ball.

2. A transportation apparatus as claimed in claim 1, wherein the planet assemblies are arranged substantially horizontally.

3. A transportation apparatus as claimed in claim 1, wherein the planet assemblies are arranged substantially vertically.

4. A transportation apparatus as claimed in any preceding claim, wherein the frame comprises upper and lower subframes extending around the balls.

5. A transportation apparatus as claimed in any preceding claim, wherein four balls are provided.

6. A transportation apparatus as claimed in any preceding claim, wherein the balls are made of PVC plastics material.

7. A transportation apparatus as claimed in any preceding claim, wherein the rotatable members comprise spheres or rollers.

8. A transportation apparatus as claimed in any preceding claim, wherein the rotatable members are made of nylon plastics material.

9. A transportation apparatus as claimed in any preceding claim and including floor jacks for inhibiting undesired movement of the apparatus.

10. A transportation apparatus as claimed in any one of claims 1 to 8 and including a generally wedge-shaped brake member for insertion between adjacent balls.

11. A transportation apparatus as claimed in any preceding claim and including means for driving the apparatus.

12. A transportation apparatus as claimed in claim 11, wherein the driving means comprises a plurality of continuously rotatable rollers which are engageable with one or more of the balls.

13. A transportation apparatus substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

14. A wheelchair incorporating a transportation apparatus as claimed in any preceding claim.