GB2378162A

GB2378162A - A manually drivenable vehicle

Info

Publication number: GB2378162A
Application number: GB0118908A
Authority: GB
Inventors: Tin Sung Yip
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-08-02
Filing date: 2001-08-02
Publication date: 2003-02-05
Also published as: GB0118908D0

Abstract

The vehicle (100), e.g. a bicycle, has a front wheel (104), a rear wheel (160), a pair of oppositely movable racks (120a, 120b) operable by a user's feet and meshing with an intermediate gear (122), one rack being extended to mesh with an input of a rear gear box (118), comprising gears with ratchet detents, to provide power in one direction only to move the rear wheel (106). Optionally, handlebars (110) on the vehicle are reciprocable longitudinally to cause a toothed sector part meshing with an input gear of a front gear box (116), having gears with ratchet teeth, to provide power in one direction to the front wheel (104). The racks (120a,b) and meshing gears have two sets of teeth (150a,b) of asymmetric form, one being reversed to the other, the form comprises a power transmitting curved surface and a rear straight angled surface.

Description

A Manually Drivenable Vehicle This invention relates to a manually drivenable vehicle and, in particular, such a vehicle with a novel power input system.

Manually drivenable vehicles, e. g. bicycles and tricycles have been in existence for a long time. While various modifications have been proposed and/or made with a view to improving the efficiency of operation of conventional bicycles, the way of driving such bicycles remains basically the same. To drive a conventional bicycle, a driver pedals two inter-connected pedals rotationally to move a first gear. The first gear is connected, via a chain, with or without an intermediate gear system, to a second gear which is,. fixed to the rear wheel of the bicycle. Movement of the first gear will thus bring about movement of the rear wheel, and thus the bicycle- In such conventional bicycles, power is inputted by rotational movement of the feet of the driver only, and power is transmitted to the rear wheel, which drives the bicycle. The front wheel only serves as a slave wheel, and for changing the direction of travel of the bicycle.

In order to enable the driver to pedal, the seat is usually situated about one metre above the ground level, which means that it is difficult to lower the centre of gravity of the bicycle. In addition, in order to allow the driver to move his thighs to drive the bicycle, the seat can only be relatively small and thus uncomfortable. Occasionally, the chain may be disengaged from the gears, and requires to be reassembled with the gears.

It is also found in practice that when a pedal is moved by

a driver through 1800 from its topmost position to its lowermost position, no power is transmitted to the gear during movement of the pedal through the first 150 and the last 300.

Similarly, when the pedal is moved through the remaining halfcycle through 180 from its lowermost position to its topmost position, no power is transmitted to the gear during movement of the pedal through the first 15 and the last 30 . Thus, in every cycle of rotation of the pedal of the conventional pedalling system, at least 25% (90 /360 ) of the power inputted by the driver into the bicycle is wasted by reason of the way in which conventional pedalling system operates. The percentage of wastage of the inputted power will in fact increase as the pedals rotate faster and faster.

Other manually drivenable vehicles have also been devised.

However, most such vehicles also employ the same pedalling system used in conventional bicycles, and improvements have mainly been focused on streamlining the shape of the vehicles. The same problems residing in the manner of operation of the conventional pedalling system still remains in such other manually drivenable vehicles.

It is thus an object of the present invention to provide a manually drivenable vehicle in which the above shortcomings are mitigated or at least to provide a useful alternative to the public.

It is a further object of the present invention to provide a manually drivenable vehicle in which the conventional pedalling system and chain are dispensed with.

According to the present invention, there is provided a

manually drivenable vehicle including at least a first wheel, first power input means operable by a user to move along a substantially straight line to input power into said vehicle, and first power transmission means for transmitting said inputted power to move at least said first wheel.

Examples of manually drivenable vehicles according to the present invention will now be described, by way of examples only, and with reference to the accompanying drawings, in which: Fig. 1 shows a left side view of a manually drivenable vehicle according to a first embodiment of the present invention ; Fig. 2 shows a simplified top view of the vehicle Shown in Fig. 1 ; Fig. 3A shows a first configuration of the first power input system in the vehicle shown in Fig. 1 ; Fig. 3B shows a second configuration of the first power input system in the vehicle shown in Fig. 1; Fig. 4A shows a first configuration of the rack and the first gear box of the vehicle shown in Fig. li Fig. 4B shows a second configuration of the rack and the first gear box of the vehicle shown in Fig. li Fig. 5 shows a toothed portion of the rack of the vehicle shown in Fig. 1; Fig. 6A to 6C are various perspective views of a gear in the vehicle shown in Fig. 1 ; Fig. 7A shows the shape and proportional dimensions of the teeth of the rack of the vehicle shown in Fig. li Fig. 7B shows the engagement of the rack shown in Fig. 5 and the gear shown in Fig. 6A ; Fig. 8 shows a second example of a claw and ratchet gear in the first gear box of the vehicle shown in Fig. 1 ;

Fig. 9 shows a part of a further example of the first gear box of the vehicle shown in Fig. 1; Fig. 10 is a simplified right perspective view of the vehicle shown in Fig. 1 ; Fig. 11A shows a first configuration of the engagement of the second power input system and the second gear box of the vehicle shown in Fig. 1 ; Fig. 11B shows a second configuration of the engagement of the second power input system and the second gear box of the vehicle shown in Fig. 1; Fig. 12A shows a top view of a manually drivenable vehicle according to a second embodiment of the present invention; and Fig. 12B shows a left side view of the vehicle shows in Fig.

12A.

Figs. 1 and 2 show a first example of a manually drivenable vehicle according to the present invention, generally designated as 100. The vehicle 100 includes a body portion 102. A front end of the body portion 102 is connected with a front wheel 104, whereas its rear end is connected with a rear wheel 106. A driver seat 108 (not shown in Fig. 2 for clarity purpose) is provided proximate and above the rear wheel 106.

A handle 110 is connected, via a bar 111, with a front yoke 112 of the body portion 102 and is swivellable relative to a cross-bar 114, so that the handle 110 is movable between the position shown in solid line and the position shown in dotted line in Fig. 1. In particular, the handle 110 is swivellable relative to the cross-bar 114 about an axis M-M, which is perpendicular to the longitudinal axis L-L of the vehicle 100. The handle 110 is also swivellable to change the direction of travel of the vehicle 100, in the conventional manner. The

handle 110 is connected with the front wheel 104 via a front gear box 116 in a manner to be discussed below.

The vehicle 100 is provided with a novel pedalling system which is connected via a rear gear box 118 to the rear wheel 106. The pedalling system includes a longer rack 120a and a shorter rack 120b engaged with each other via a gear 122.

Each of the racks 120a, 120b has a respective pedal 124a, 124b on which a foot of a user may rest to operate the racks 120a, 120b. In particular, both the racks 120a, 120b may be operated to reciprocate in directions indicated by the bidirectional arrow A shown in Fig. 1. In particular, each rack 120a, 120b is operable to move along a respective straight line which is parallel to the longitudinal axis L-L of the vehicle 100. An end part 126 of the longer rack 120a is engaged with the rear gear box 118 in a manner to be discussed below.

Figs. 3A and 3B show in further detail the structure and arrangement of the racks 120a, 120b, the gear 122, and the rear gear box 118. As can be seen in Fig. 3A, both the racks 120a, 120b are in mesh with the gear 112. In particular, a first toothed portion 123 of the rack 120a meshes with the gear 122. The gear 122 is secured to the vehicle 100 such that only rotational movement relative to the vehicle 100 is allowed. By way of such an arrangement, the racks 120a and 120b will always move synchronously in opposite directions.

As shown in Fig. 3A, when the rack 120a is moved rightward, the rack 120b will move leftward. Similarly, as shown in Fig. 3B, when the rack 120b is moved rightward, the rack 120a will move leftward. The feet of the user may thus act on the racks 120a and 120b alternately to operate the pedalling system. As

no rotational movement of the thighs of the driver is required for operating this pedalling system, the seat 108 may be larger and thus more comfortable to the driver. It can also be seen that, during operation of this new pedalling system, the longer rack 120a reciprocates relative to the rear gear box 118.

As can be seen in Figs. 3A and 3B, at the end part 126 of the longer rack 120a is provided with a second toothed portion 128. Schematic diagrams of the engagement of the second toothed portion 128 of the longer rack 120a with a gear train 130 in the rear gear box 118 are shown in Figs. 4A and 4B. t The gear train 130 includes a gear 132 which meshes, on the one hand, with the second toothed portion 128 of the longer rack 120a and, on the other hand, with external teeth of two claw and ratchet gears 134,136. Each of the claw and ratchet gears 134,136 includes a respective central rotatable claw portion 134a, 136a fixed with a smaller gear 134b, 136b. Each claw and ratchet gear 134,136 also includes a respective outer gear ring 134c, 136c. The smaller gear 134b of the claw and ratchet gear 134 meshes with a gear 138, which in turn meshes with a gear 140. The gear 140 also meshes, on one hand, with the central gear 136b of the claw and ratchet gear 136 and, on the other hand, with a gear 142.

When the rack 120a moves rightward, as shown in Fig. 4A, the gear 132 will rotate in the clockwise direction, which causes the outer gear ring 134c, 136c of the respective claw and ratchet gear 134,136 to rotate in the anti-clockwise direction. Because of the positioning of the claw portion 136a with respect to inner ratchet teeth 136d of the claw and

ratchet gear 136, rotation of the outer gear ring 136c in the anti-clockwise direction will bring about corresponding rotation of the claw portion 136a in the anti-clockwise direction. The central gear 136b then causes the gear 140 to rotate in the clockwise direction, which in turn causes the gear 142 to rotate in the anti-clockwise direction.

Because of the positioning of the claw portion 134a with respect to inner ratchet teeth 134d of the claw and ratchet gear 134, rotation of the outer gear ring 134c in the anticlockwise direction will not bring about any rotational movement of the claw portion 134a. On the other hand, the clockwise rotation of the gear 140 causes the gelai 138 to rotate in the anti-clockwise direction, which in turn causes the central gear 134b, and thus the claw portion 134a, to rotate in the clockwise direction.

When the rack 120a moves leftward, as shown in Fig. 4B, the gear 132 will rotate in the anti-clockwise direction, which causes the outer gear ring 134c, 136c of the respective claw and ratchet gears 134,136 to rotate in the clockwise direction. Because of the positioning of the claw portion 134a with respect to the inner ratchet teeth 134d of the claw and ratchet gear 134, rotation of the outer gear ring 134c in the clockwise direction will bring about corresponding rotation of the claw portion 134a in the clockwise direction. The central gear 134a then causes the gear 138 to rotate in the anti-clockwise direction. The gear 140 will then be caused to rotate in the clockwise direction, which in turn causes the gear 142 to rotate in the anti-clockwise direction.

Because of the positioning of the claw portion 136a with

respect to inner ratchet teeth 136d of the claw and ratchet gear 136, rotation of the outer gear ring 136c in the clockwise direction will not bring about any rotational movement of the claw portion 136a. On the other hand, the clockwise rotation of the gear 140 will cause the small gear 136b to rotate in the anti-clockwise direction.

It can be seen that, by way of the above arrangement, the gear 142 will always rotate in the same anti-clockwise direction irrespective of whether the rack 120a moves rightward or leftward. It should also be understood that the gear 132 may be dispensed with, so that the toothed portion 128 of the rack 120a directly engages both the outer gear rings 134c, 136c of the respective claw and ratchet gear 134, 136.

In the vehicle 100, the gear 142 is directly fixed with an axle 144 of the rear wheel 106, so that reciprocating movement of the rack 120a will bring about rotation of the rear wheel 106 in one direction only. Alternatively, the gear 142 may be engaged with the axle 144 via one or more gears, to drive the rear wheel 106.

It is found in practice that power can be inputted into the vehicle 100 when the rack 120a reciprocates relative to the rear gear box 118, in which the distance travelled in each direction is as little as 3cm.

It should also be noted that, if the rear wheel 106 rotates on its own, e. g. when travelling downhill, the gear 142 will rotate in the anti-clockwise direction. This will cause the gear 140 to rotate in the clockwise direction, which will in

turn cause the gear 138 to rotate in the anti-clockwise direction. However, although clockwise rotation of the gear 140 will cause the small gear 136b to rotate in the anticlockwise direction, such will not bring about any rotational movement of the outer gear ring 136c of the claw and ratchet gear 136. Similarly, although anti-clockwise rotation of the gear 138 will cause the small gear 134b to rotate in the clockwise direction, such will not bring about any rotational movement of the outer gear ring 134c. Thus the gear 132 and the rack 120a will not move in response to free rotational movement of the rear wheel 106. Put another way, power can only be transmitted from the rack 120a to the gear 142, and thus the rear wheel 106, but not vice versa.

As the racks 120a, 120b will move forward and backward relative to the gear 122, and the second toothed portion 128 of the rack 120a will also move forward and backward relative to the gear 132, a novel gear teeth arrangement is provided for better transmission of power.

As can be clearly seen in Fig. 5, two rows of teeth 146a, 146b are formed on a surface of the rack 120a to form the first toothed portion 123. While the row of teeth 146a are inclined towards one longitudinal end of the rack 120a, the row of teeth 146b are inclined towards another longitudinal end of the rack 120. While this novel gear teeth arrangement is shown in the context of the first toothed portion 123 of the rack 120a, it may also be provided on the shorter rack 120b, and the second toothed portion 128 at the end part 126 of the rack 120a.

A similar gear teeth arrangement is provided on a

circumferential rim 148 of the gear lii, as shown in tigs. bA to 6C. It can be seen that, similarly, two rows of teeth 150a, 150b are provided, one inclined towards a first direction, and the other inclined towards a second direction which is opposite to the first direction. This gear teeth arrangement may also be provided on the gear 132, and the outer gear rings 134c, 136c of the claw and ratchet gears 134, 136.

Fig. 7A shows the proportional dimensions and shape of teeth 152 of the novel gear teeth arrangement discussed above.

It can be seen that the teeth 152 are asymmetrical, in that while a side 154 of the tooth 152 is straight, an opposite side 156 of the tooth 152 is curved, and the teeth 152 are inclined towards the curved side 154. As can be seen more clearly in Fig. 7B, when the gear 122 meshes with the rack 120a, the curved sides of a respective tooth contact over a surface, but not a line as in conventional gear teeth arrangements. Such a novel gear teeth arrangement significantly enhances the meshing and thus transmission of power between the gear 122 and the rack 120a, and other components incorporating such a novel arrangement. Providing two sets of parallel yet oppositely inclined teeth 146a, 146b on the rack 120a, and 150a, 150b on the gear 122 ensures that the better meshing between the rack 120a and the gear 122 is achieved irrespective of the relative direction of movement between the rack 120a and the gear 122.

It is found in practice and experiments that the abovedescribed novel gear teeth arrangement is superior to both the conventional helical gear arrangement and double helical gear arrangement in terms of both the area of contact and

smoothness during operation and transmission of power.

Fig. 8 shows an alternative example of a claw and ratchet gear 160 with an outer gear ring 162 having a number of external teeth 164 and a number of internal ratchet teeth 166.

The gear 160 includes a central gear 168 with four pawls 170a, 170b, 170c, 170d which are biased outwardly away from the gear 168. Both the outer gear ring 162 and the central gear 168 are freely rotatable about a central axis which is perpendicular to the plane of the paper. Fixedly engaged with the central gear 168 and rotatable simultaneously therewith is a gear with external teeth (not shown for clarity purpose) for engagement with other gears to form the gear train asrshown in Figs. 4A and 4B.

In the outer gear ring 162, there are eighteen internal ratchet teeth 166, each occupying an angle of 200. Engagement of the outer gear ring 162 with the central gear 168 will occur when the outer gear ring 162 rotates relative to the central gear 168 in the clockwise direction. In the gear 160 as shown in Fig. 8, the pawl 170a is engaged with a ratchet tooth, whereas the pawl 170b is 1/4 way towards engagement with the next ratchet tooth, the pawl 170c is halfway towards engagement with the next ratchet tooth, and the pawl is 3/4 way towards engagement with the next ratchet tooth.

It means that, by way of such an arrangement, irrespective of the original relative position between the outer gear ring 162 and the central gear 168, the outer gear ring 162 will only have to rotate a maximum angle of 5 (i. e. 20 /4) to engage with a pawl of the central gear 168, whereby the outer gear ring 162 is engaged with the central gear 168 for

simultaneous clockwise rotational movement. This represents a maximum wastage of inputted power of 1.39% (i. e. 5 /360 ).

With the same number of internal ratchet teeth 166 in the outer gear ring 162, the maximum wastage of inputted power will decrease with the increase in the number of pawls in the central gear 168. With the same eighteen internal ratchet teeth 166 in the outer gear ring 162, if the number of pawls in the central gear 168 is increased to five, the maximum angle of rotation of the outer gear ring 162 relative to the central gear 168 to achieve engagement therebetween is 4 , and the maximum wastage of inputted power will thus decrease to 1. 11%. With further increase of the number of pawls to six, the maximum angle of rotation of the outer gear ring 162 relative to the central gear 168 to achieve engagement therebetween is further reduced to 3. 3 , and the maximum wastage of inputted power will further decrease to 0.93%.

Such represents a significant reduction in the wastage of inputted power, when compared with about 25% in the conventional rotational pedalling system.

To reduce the size of the rear gear box 118, the gears 132 and the claw and ratchet gears 134,136 shown in Figs. 4A and 4B may alternatively be arranged in the manner as shown in Fig. 9. In this arrangement, a gear 132'corresponds to the gear 132 in Figs. 4A and 4B. The gear 132'is fixed on each of its two major surfaces with a respective outer ratchet ring

134c', 136c'for simultaneous movement. A gear member 137'is engaged with the ratchet ring 136c'for relative rotational movement about an axis R-R. The gear member 137'includes a gear 136b'fixedly attached with a claw member 136a'with a pawl 170a'.

If the gear 132'rotates in the direction indicated by the arrow P about the axis R-R in Fig. 9, the pawl 170a'will engage with an inner tooth of the ratchet ring 136c'and be brought into simultaneous rotational movement in the direction indicated by the arrow P about the same axis R-R. The gear 136b'will thus also simultaneously rotate in the same direction and about the same axis. However, if the gear 132' rotates in the direction indicated by the arrow Q in Fig. 9, there will be no engagement between the pawl 170a'and the ratchet ring 136c', so that the gear member 137'will not be set into rotational movement.

A gear member 139'is engaged with the ratchet ring 134c' for relative rotational movement about the axis R-R. The gear member 139'includes a gear 134b'fixedly attached with a claw member 134a'with a pawl 170b'. If the gear 132'rotates in the direction indicated by the arrow Q about the axis R-R in Fig. 9, the pawl 170b'will engage with an inner tooth of the ratchet ring 134c'and be brought into simultaneous rotational movement in the direction indicated by the arrow Q about the same axis R-R. The gear 134b'will thus also simultaneously rotate in the same direction and about the same axis. However, if the gear 132'rotates in the direction indicated by the arrow P in Fig. 9, there will be no engagement between the pawl 170b'and the ratchet ring 134c', so that the gear member 139'will not be set into rotational movement.

Turning to Fig. 10, such shows a simplified vehicle 100 in which the pedalling system is not shown for clarity purpose. It can be seen that a fan-shaped structure 200 is fixedly engaged with the bar 111 of the handle 110. The fan-shaped

structure 200 is engaged with and movable relative to the front gear box 116 in a manner to be discussed below.

Figs. 11A and 11B show the engagement between the fanshaped structure 200 and the front gear box 116. It can be seen that the front gear box 116 is of essentially the same construction as the rear gear box 118 shown in Figs. 4A and 4B, except that the fan-shaped structure 200 is in direct engagement with two claw and ratchet gears 203 via a set of teeth 204 provided on an outer arc rim 202 of the fan-shaped structure 200. The fan-shaped structure 200 is swivellable relative to the front gear box 116 to cause the two claw and ratchet gears 203 to rotate. However, as in the case of the arrangement in the rear gear box 118 discussed above, irrespective of the direction of movement of the fan-shaped structure 200 relative to the front gear box 116, a gear 206 will always rotate in the anti-clockwise direction.

The set of teeth 204 of the fan-shaped structure 200 may be in the form of the novel gear teeth arrangement discussed above and shown in Figs. 5,7A and 7B. In addition, external gears 203a of outer gear rings 203b of the claw and ratchet gears 203 may also incorporate the same novel gear teeth arrangement, for better engagement with the teeth 204 of the fan-shaped structure 200, and thus better transmission of power from the fan-shaped structure 200 to the claw and ratchet gears 203.

The gear 206 is directly fixed with an axle 208 of the front wheel 104, so that swivelling movement of the handle 110 will bring about rotation of the front wheel 104 in one direction only. Alternatively, the gear 206 may be engaged

with the axle 208 via one or more gears to drive the front wheel 104.

It can thus be seen that the vehicle 100 may be powered by the hands, in addition to or in place of, the feet of the user. In addition, power may be inputted into the front wheel 104, in addition to or in place of, the rear wheel 106, of the vehicle 100.

Similar to the engagement between the rack 120a and the rear gear box 118 discussed above, free rotation of the front wheel 104, and thus the gear 206 of the front gear box 116, will not bring about corresponding rotational movement of the outer gear rings 203b of the claw and ratchet gears 203.

There will thus also be no consequential swivelling movement of the fan-shaped structure 200.

Figs. 12A and 12B show a manually drivenable vehicle according to a further embodiment of the present invention, generally designated as 300. A main difference between the vehicle 100 and the vehicle 300 is that, in the vehicle 300, a seat 302 is significantly lowered relative to a body 304, e. g. at roughly 60cm above the ground level. This is made possible as it is no longer necessary to allow room for the driver to rotate his/her thighs to operate the new pedalling system, as in the case of operating the traditional pedalling system.

With the lowering of the seat 302 relative to the body 304, the centre of gravity of the vehicle 300 can be lowered, in particular when a driver is sitting on it, which would in turn enhance the performance of the vehicle 300.

It should be understood that the above only illustrates

examples whereby the present invention may be carried out, and that various modifications and/or alterations may be made thereto without departing from the spirit of the invention.

It should also be understood that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any appropriate sub-combinations.

Claims

CLAIMS :- 1. A manually drivenable vehicle including at least a first wheel, first power input means operable by a user to move along a substantially straight line to input power into said vehicle, and first power transmission means for transmitting said inputted power to move at least said first wheel.
2. A vehicle according to Claim 1 wherein said first power input means is adapted to be operated by at least a foot of said user.
3. A vehicle according to Claim 2 wherein said first power input means is adapted to be operated by both feet of said user.
4. A vehicle according to Claim 1 wherein said first power input means is adapted to reciprocate along said substantially straight line to input power into said vehicle.
5. A vehicle according to Claim 1 wherein said first power input means includes at least a first rack member.
6. A vehicle according to Claim 5 wherein said first rack member is movable reciprocally along its length to input power into said vehicle.
7. A vehicle according to Claim 5 wherein said first rack member is movable in a first direction and a second direction to input power into said vehicle.
8. A vehicle according to Claim 7 wherein said first and second directions are substantially opposite to each other.
9. A vehicle according to Claim 8 wherein said first wheel is adapted to rotate in a pre-determined direction irrespective of the direction of movement of said first rack member.
10. A vehicle according to Claim 5 wherein said first power

<Desc/Clms Page number 18>

input means includes at least a second rack member which is movable synchronously with and relative to said first rack member.
11. A vehicle according to Claim 10 wherein said first and second rack members are adapted to move relative to each other in opposite directions.
12. A vehicle according to Claim 10 wherein teeth of said first rack member face teeth of said second rack member.
13. A vehicle according to Claim 10 wherein both said first and second rack members are in mesh with an intermediate gear member.
14. A vehicle according to Claim 5 wherein said first rack member includes two rows of asymmetrical teeth, and wherein each said row of teeth are inclined towards a different direction.
15. A vehicle according to Claim 10 wherein said second gear member includes two rows of asymmetrical teeth, and wherein each said row of teeth are inclined towards a different direction.
16. A vehicle according to Claim 13 wherein said intermediate gear member includes two rows of asymmetrical teeth, and wherein each said row of teeth are inclined towards a different direction.
17. A vehicle according to Claim 1 wherein said first power transmission means includes a gear system relative to which said first power input means is movable.
18. A vehicle according to Claim 17 wherein said first rack member is in mesh with at least a first gear member of said gear system.
19. A vehicle according to Claim 18 wherein said first rack member is adapted to move relative to said first gear member in different directions to cause said first gear

<Desc/Clms Page number 19>

member to rotate in two different directions.
20. A vehicle according to Claim 19 wherein said gear system includes a second gear member which is adapted to rotate in a pre-determined direction irrespective of the direction of rotation of said first gear member.
21. A vehicle according to Claim 1 wherein said first wheel is a rear wheel of said vehicle.
22. A vehicle according to Claim 1 further including second power input means operable by a user to swivel to input power into said vehicle.
23. A vehicle according to Claim 22 further including second power transmission means for transmitting said power inputted from said second power input means to move at least a second wheel of said vehicle.
24. A vehicle according to Claim 22 wherein said second power input means is adapted to be operated by at least a hand of said user.
25. A vehicle according to Claim 24 wherein said second power input means is adapted to be operated by both hands of said user.
26. A vehicle according to Claim 22 wherein said second power input means is swivellable about an axis substantially perpendicular to a longitudinal axis of said vehicle.
27. A vehicle according to Claim 23 wherein said second power transmission means includes a gear system relative to which said second power input means is movable.
28. A vehicle according to Claim 27 wherein said second power input means includes a toothed portion in mesh with at least two claw and ratchet gears of said gear system of said second power transmission means.
29. A vehicle according to Claim 28 wherein said second power input means is swivellable relative to said gear system of

<Desc/Clms Page number 20>

said second power transmission means in two different directions to cause a respective outer portion of each said claw and ratchet gear to rotate in two different directions.
30. A vehicle according to Claim 27 wherein said gear system of said second power transmission means includes a gear member which is adapted to move in a pre-determined distance irrespective of the direction of swivelling movement of said second power input means.
31. A vehicle according to Claim 23 wherein said second wheel is a front view of said vehicle.
32. A manually drivenable vehicle substantially as herein described and with reference to the accompanying drawings.