GB2136744A - Human-powered vehicle - Google Patents

Abstract

A human-powered vehicle comprises a frame 1 on which is mounted a seat 5, a front wheel 8 driven by pedals 4 and a pair of smaller rear wheels 22 mounted on an axle 23 in such a way that as the frame is tilted to one side the axle 23 pivots in the horizontal plane, thus steering the vehicle. The wheels 22 and axle 23 may be part of a skateboard truck. Handgrips 15 are mounted on the frame. <IMAGE>

Description

SPECIFICATION Human-powered vehicle This invention relates to a human-powered vehicle, primarily for recreational purposes.

In recent years, the skateboard has become popular, particularly among older children. The skateboard comprises a substantially rigid board upon which the rider stands and underneath which is mounted a pair of "trucks", one at the front and one at the rear. Each truck comprises a pair of wheels mounted by means of low-friction bearings on an axle, the axle being mounted on a mounting flange so as to pivot in the horizontal plane as the flange is tilted in the vertical plane containing the axle.This is achieved by mounting the axle on an inclined pillar extending from the flange and having a resilient insert and providing on the axle a strut which engages the flange so as to be movable within limits, the movable strut being positioned behind the inclined pillar in the direction of motion in the case of the rear truck and in front of the inclined pillar in the direction of motion in the case of the front truck.

When the rider tilts the board to one side by means of his body weight, the axles of the trucks pivot in the horizontal plane so as to steer the skateboard in the direction in which the board is tilted.

The popularity of skateboards has, however, recently declined simply because they are no longer a novelty.

The object of the present invention is to provide a human-powered vehicle which is extremely manoeuvrable and capable of providing an exciting ride.

According to the invention, there is provided a human-powered vehicle comprising a frame on which is mounted a seat, a pedal-driven wheel rotatably mounted on the frame and a pair of wheels mounted on an axle, the axle being mounted on the frame so that as the frame is tilted to one side or the other, the axle is pivoted in the horizontal plane, thus steering the vehicle, and the driven wheel being of larger diameter than the pair of wheels.

By virtue of the provision of a relatively large wheel driven by means of pedals, the vehicle is capable of higher speeds than a skateboard, yet is highly manoeuvrable by virtue of the arrangement whereby tilting of the frame by movement of the rider's body weight automatically steers the vehicle.

Preferably the driven wheel is mounted on the frame in front of the seat in the intended direction of travel and the pair of wheels behind the seat.

The driven wheel is preferably driven by means of pedals via a conventional chain. This permits the pedals to be positioned in front of the driven wheel which is in turn positioned in front of the seat, giving rise to a compact arrangement. Gearing, for example a hub or derailleur gear, may optionally be provided.

Whilst brakes may be provided, it is preferred to use a "fixed" driven wheel, i.e. one without a freewheel, thus eliminating the need for brakes. The driven wheel is preferably faired in in the region between its center and its rim, thus preventing the rider, or his clothing, from becoming entangled with the wheel.

Alternatively or in addition the wheel may be partially enclosed, the enclosure also acting as a mudguard. The driven wheel in one preferred embodiment is a spoked wheel with a diameter of 20" (510mm) and is provided with a pneumatic tyre.

A pair of handgrips are preferably provided on the frame. This permits the rider to improve his control over the machine and increases the force which can be transmitted to the pedals.

The pair of wheels mounted on an axle are of comparatively small diameter, for example about 2' (51mum). In a preferred embodiment, a conventional skateboard truck is used to provide the pair of wheels. The turning circle of the vehicle can be varied by adjusting the angle of the inclined pillar reiative to the vertical. This is in turn achieved by adjusting the angle of the mounting flange. A combination of stability and manoeuvrability is achieved by positioning the pair of wheels to the rear of the seat.

The frame can be formed of any suitable material, preferably tubular metal such as steel, but plastics may also be suitable. In a preferred embodiment the frame consists primarily of two tubes positioned side-by-side and lying in the same plane, the tubes being contiguous and welded together at the rear end and joined to a pedal-bearing bracket at the front end, and spaced apart behind the bracket to allow the driven wheel to be mounted between them.

Mountings for the wheels, handgrips and a support for the seat are preferably welded to the tubes.

In the accompanying drawings: Figure 1 is a plan view of an exemplary preferred embodiment of the invention; and Figure 2 is a side elevation of the embodiment shown in Figure 1.

As shown in the drawing, a human-powered vehicle comprises a frame 1 formed of tubular steel.

The frame comprises two tubes 2 which extend in a common plane from a tubular bracket 3 at the front of the vehicle to the rear of the vehicle. A pair of pedals 4 are rotatably mounted in the bracket 3. The tubes are identical to one another and are only bent twice in a single plane. The rear end portions of the tubes are then welded together and the tubes are welded to the bracket 3. Manufacture of the frame is thus extremely simple and economical. An upholstered seat 5 is secured to the tubes 2 and a backrest portion of the seat is supported by a tubular member 6 welded to the tubes 2 and a tubular strut 7 welded at one end to the tube 6 and at the other end to the tubes 2.

A driven wheel 8 is rotatably mounted in front of the seat 5 on the frame 1 between the tubes 2 in a conventional manner, the axle 9 of the wheel being demountably secured to brackets 10 by means of nuts 11, one bracket 10 being provided on each tube 2. Drive from the pedals 4 is transmitted to the wheel 8 by means of a chain 12 and fixed wheel sprockets 13, 14. The wheel 8 is provided with a pneumatic tyre 17 and is faired in to prevent the rider's body or clothes becoming entangled with the wheel.

A pair of handgrips 15 are also mounted on the frame 1. Each handgrip 15 is mounted on a straight tubular member 16 welded to and extending outwardly from one of the tubes 2.

At the rear end of the frame 1, there is provided a flange 18 secured to the tubes 2 by means of a web 19. A skateboard truck 20 (known peruse) is secured to the flange 18 by means of four nuts and bolts 21.

The truck 20 comprises two wheels 22 mounted on an axle 23 by means of low-friction bearings. The axle is mounted on a supporting flange 24 by means of a rearwardly inclined pillar 25 and a strut 26 fixed to the axle. The pillar 25 includes an elastomeric washer 27 intermediate its ends. The upper end of the strut 26 is received in a support 28 which permits the end of the strut 26 to rotate and to undergo a limited degree of movement relative to the flange 24.

The effect of this construction is that, as the flange is tilted to one side, the axle 23 pivots in the horizontal plane so that the wheel 22 on said one side trails behind the other wheel 22, thus steering the vehicle in the direction of said one side. Of course, as the flange is tilted towards the other side, the vehicle is steered in the direction of the other side. The degree of responsiveness to tilting of the vehicle can be adjusted by interposing a wedge-shaped member between the flange 18 and the flange 24. The greater the angle of the wedge, the tighter will be the turning circle of the vehicle in response to a predetermined degree of tilting.

It will, of course, be appreciated that the particular dimensions of the vehicle can be varied having regard, for example, to the size of the intended rider and the desired handling characteristics. However, a vehicle having good performance in use has been constructed having a driven wheel diameter of 20" (approximately 510mum), a horizontal spacing between the axes of wheel 8 and wheels 22 of 34.5" (877mm) and a diameterforwheels 22 of 2" (51 mm).

In a modification of the vehicle described with reference to the drawing, a housing for the wheel 8 may be provided to prevent the rider or his clothing coming into contact with the wheel 8. The housing, could for example, enclose at least a rearward sector of the portion of the wheel extending abovethe tubes 2. Such a housing would obviate the need to fair in the wheel 8, so that a conventional spoked wheel could be used.

It will also be appreciated that the arrangement whereby the wheel 8 is driven may be modified.

Thus, for example, multi-speed gearing as known for use in bicycles, for example a hub or derailleur gear, may be provided. Furthermore, the chain 12 could be dispensed with if the axis about which the pedals 4 rotate was concentric with the axis of wheel 8.

Claims (12)

1. A human-powered vehicle comprising a frame on which is mounted a seat, a pedal-driven wheel rotatably mounted on the frame and a pair of wheels mounted on an axle, the axle being mounted on the frame so that as the frame is tilted to one side or the other, the axle is pivoted in the horizontal plane, thus steering the vehicle, and the driven wheel being of larger diameter than the pair of wheels.

2. A human-powered vehicle as claimed in claim 1 wherein the driven wheel is mounted on the frame in front of the seat in the intended direction of travel and the pair of wheels is mounted behind the seat.

3. A human-powered vehicle as claimed in claim 1 or 2 wherein the driven wheel is driven by means of pedals via a chain.

4. A human-powered vehicle as claimed in claim 1, 2 or 3 wherein the driven wheel is positively drivable by the pedals without an intervening freewheel.

5. A human-powered vehicle as claimed in any preceding claim wherein the driven wheel is faired in the region between its centre and its rim.

6. A human-powered vehicle as claimed in any preceding claim wherein the driven wheel is partially enclosed.

7. A human-powered vehicle as claimed in any preceding claim wherein the driven wheel is of the order of 510 mm diameter.

8. A human-powered vehicle as claimed in any preceding claim wherein the pair of wheels are each of the order of 51 mm diameter.

9. A human-powered vehicle as claimed in any preceding claim wherein the pair of wheels are part of a skateboard truck.

10. A human-powered vehicle as claimed in any preceding claim wherein the frame comprises two tubes positioned side-by-side and lying in the same plane, the tubes being contiguous and welded together at the rear end and joined to a pedalbearing bracket at the front end, and spaced apart behind the bracket to allow the driven wheel to be mounted between them.

11. A human-powered vehicle as claimed in any preceding claim wherein a pair of handgrips are provided on the frame.

12. A human-powered vehicle substantially as hereinbefore described with reference to the accompanying drawing.