STEERING ASSEMBLY USING TWO LEVERS

Technical Field

The present invention relates to a vehicle steering assembly. The steering assembly is particularly suited to land vehicles having two front steerable wheels, such as "all-terrain vehicles" and the like. However, the steering assembly is also suited to other vehicles such as snowmobiles and personal watercraft.

Background

Personal vehicles such as all-terrain vehicles (also known as quad bikes), snowmobiles and personal watercraft employ handlebar systems that have originated from motorcycles. Many of these personal vehicles do not use a twist throttle control of the type used on motorcycles. This is because such personal vehicles, and in particular quad bikes, suffer the disadvantage that in a turn the handlebar is moving to the same point the rider wants to put his body. It would be difficult for a driver to control a twist throttle when in the turn the handle bar is near his lower torso. Instead such personal vehicles typically employ a lever or paddle throttle control. Furthermore, many drivers of such personal vehicles find the use of conventional handlebars uncomfortable and the vehicle difficult to control, as the handgrip grip closest to the direction of turn is brought towards the body of the driver.

The present invention seeks to overcome at least some of the disadvantages of the prior art personal vehicles.

Summary of Invention

According to a first aspect the present invention consists of a steering assembly for a vehicle having two front steerable wheels, said assembly comprising two adjacent steering levers disposed on opposite sides of the longitudinal axis of said vehicle near the fore end of said vehicle, said steering levers connected to said wheels via a linkage arrangement and are each adapted to be moved substantially forwardly and rearwardly, wherein in order to effect a turn said levers are moved simultaneously in substantially opposite directions to each other with the one being closest to the direction of turn being moved substantially rearwardly and the other moved substantially forwardly, characterised in that as each of

said levers is moved, each laterally moves away from said longitudinal axis during the rearward movement and towards said longitudinal axis during forward movement.

Preferably said levers are provided with respective handgrips adapted to be gripped by a driver of the vehicle, said driver adapted to be seated on a seat disposed along said longitudinal axis aft of said levers and said driver is straddled thereon with a leg either side of said vehicle, such that when driver effects a turn by moving said levers in substantially opposite directions the driver's body weight shifts towards the direction of said turn.

Preferably said throttle control is a twist grip arrangement on one of said handgrips.

Preferably in one embodiment said vehicle has two rear wheels. Preferably said vehicle is an all terrain vehicle

Preferably in another embodiment said vehicle has one rear wheel.

According to a second aspect the present invention consists of a steering assembly for a vehicle having at least one steerable member, said vehicle having a seat disposed along said longitudinal axis and being of the type in which the driver of said vehicle is straddled on said seat with a leg either side of said vehicle, said steering assembly comprising two adjacent steering levers disposed on opposite sides of the longitudinal axis of said vehicle • near the fore end of said vehicle, said steering levers connected to said steerable member via a linkage arrangement, each of said levers adapted to be moved substantially forwardly and rearwardly, wherein in order to effect a turn said levers are moved simultaneously in substantially opposite directions to each other with the one being closest to the direction of turn being moved substantially rearwardly and the other moved substantially forwardly, and wherein as said levers are moved each laterally moves away from said longitudinal axis during the rearward movement and towards said longitudinal axis during forward movement.

Preferably when said driver effects a turn by moving said levers in substantially opposite directions, the driver's body weight shifts towards the direction of said turn.

Preferably said levers are provided with respective handgrips adapted to be gripped by said driver.

Preferably the throttle control of said vehicle is a twist grip arrangement on one of said handgrips.

Preferably in one embodiment said vehicle is a land vehicle.

Preferably said at least one steerable member is two steerable front wheels.

Preferably said land vehicle has one or two rear wheels.

Preferably said land vehicle is an all terrain vehicle.

Preferably in another embodiment said at least one steerable member is a steerable front ski or pair of front skis. Preferably said vehicle is a snowmobile.

Preferably in a further embodiment said vehicle is a personal watercraft. Preferably said personal watercraft utilizes jet propulsion.

Brief Description of Drawings

Fig. 1 is a perspective view of an all-terrain vehicle having a steering assembly in accordance with a first embodiment of the present invention.

Fig. 2 is a schematic plan view of the front end of the vehicle shown in Fig. 1;

Fig. 3 is a schematic elevation view of the front end of the vehicle shown in Fig. 1.

Fig. 4 is a schematic end view of the front end of the vehicle shown in Fig. 1.

Fig. 5 is a schematic plan view of the front end of the vehicle shown in Fig. 1 as a right turn is being effected.

Fig. 6 is a schematic elevation view of the front end of the vehicle shown in Fig. 1. as a right turn is effected.

Fig. 7 is a schematic end view of the front end of the vehicle shown in Fig. 1. as a right turn is effected, with the wheels omitted.

Fig. 8 is a perspective view of a person watercraft having a steering assembly in accordance with a second embodiment of the present invention.

Mode of Carrying Out Invention

Figs. 1 to 4 depict an all-terrain vehicle 1 having a steering assembly in accordance with a first embodiment of the present invention. Vehicle 1 has two front wheels 2 and a seat 3 is disposed aft thereof and on the longitudinal axis L. The vehicle is of a personal type such that the driver (not shown) straddles seat 3 with his (or her) legs disposed on either side of vehicle 1. The longitudinal axis L lies on central vertical plane P shown in Fig. 4.

The steering assembly comprises two adjacent steering levers 5, 6 disposed on opposite sides of the longitudinal axis L near the fore end of vehicle 1. Looking at vehicle 1 in the plan view of Fig. 1, lever 5 is the left lever and lever 6 is the right lever. Steering levers 5, 6 are connected to wheels 2 via a linkage arrangement 9. Each of the levers 5, 6 is adapted to be moved substantially forwardly and rearwardly. In order to effect a turn, levers 5, 6 are moved simultaneously in substantially opposite directions to each other, with the one being closest to the direction of turn being moved substantially rearwardly and the other moved substantially forwardly. Also as levers 5, 6 are moved, each laterally moves away from longitudinal axis L during a rearward movement and towards said longitudinal axis L during a forward movement.

Figs. 5 to 7 depict the configuration of the levers as a right turn is being effected. In order to effect a right turn as shown in Fig. 4, the right lever 6 is moved substantially rearwardly and the left lever 5 is moved substantially forwardly. Likewise as the levers 5, 6 are moved to effect the right turn, the rearwardly moving lever 6 is moved away from the longitudinal axis L and the forwardly moving lever 5 is moved towards the longitudinal axis L.

The levers 5, 6 are provided at their free ends with handgrips 7, 8 respectively. These handgrips 7, 8 are adapted to be gripped by the driver of vehicle 1. When the driver effects a right turn by moving the levers 5, 6 into the configuration as shown in Fig. 4, the driver's body weight must shift towards the right thus ensuring the driver's body weight is correctly shifted for the ensuing turn. As the driver's left hand and left arm are extended forwardly and slightly towards longitudinal axis L, his right hand and right arm move rearwardly and slightly away from the longitudinal axis L. This movement slightly away from the longitudinal axis L by the right lever 6, reduces the likelihood of handgrip 8 contacting the driver's torso.

Of course, in order to turn to the left (not shown) the driver's right hand, right arm and lever 6 would move forwardly and slightly towards the longitudinal axis L, and the left hand, left arm and lever 5 would move rearwardly and slightly away from longitudinal axis L. In effecting the left turn lever configuration, the driver's body weight shifts towards the left, thus ensuring the driver's body weight is correctly shifted for the ensuing left turn.

As the steering assembly, during a turn, places the handgrips 7, 8 where they do not engage with the driver's body, then it is possible to utilise a "twist grip" throttle control mounted to one of the handgrips 7, 8.

In the abovementioned embodiment of the all-terrain vehicle (quad bike) 1, the lever configuration of the above described embodiment overcomes some of the disadvantages of prior art quad bikes. Firstly, this is because the lever configuration ensures that the driver's body weight is shifted appropriately when entering a turn. Secondly, this shifting of the driver's body weight in combination with a movement of the levers, minimises the risk of the handle grips contacting the driver's body. Both of these advantages lead to better control of the all-terrain vehicle, along with the use of a twist grip throttle control. Similar advantages can also be found when the steering assembly of the above described first embodiment is employed in a "three wheeler" vehicle having two front wheels and a single rear wheel. Where the steering assembly of the first embodiment is employed in a "three wheeler", it may for instance be a vehicle which is operated at speeds significantly greater than that of all-terrain vehicles .

It is to be understood that the above has been given by way of illustrative embodiment of the invention. AU modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as described herein. For example, the linkage arrangement 9, has been shown in a simple arrangement for clarity purposes and ease of reference. However, it should be understood that the linkage arrangement could in other embodiments be of a more sophisticated or complicated design. For example, whilst levers 5, 6 of the above described embodiment is pivoted at a location near the lower portion as shown in Fig. 3, it should be understood that in other not shown embodiments the levers may be shorter and pivoted at a different location, vertically relative to that shown in Fig. 3.

It should also be understood that the present invention is not limited to wheeled land vehicles. For instance the vehicle of the present invention could in another embodiment be a snowmobile having its front ski (or pair of skis) steerable rather than the wheels of the above described wheeled embodiment. In another embodiment the vehicle of the present invention may be a personal watercraft 21 powered by water jet or other propulsion means, as shown in Fig. 8. Like that of vehicle 1, watercraft 21 would have steering levers that would be movable forwardly and rearwardly, and in order to effect a turn these levers are moved simultaneously in substantially opposite directions to each other, with the one being closest to the direction of turn being moved rearwardly and the other lever moved forwardly. As the levers are moved, each laterally moves away from the longitudinal axis of watercraft 21 during rearward movement, and towards the longitudinal axis during forward movement.

Whilst each of these not shown embodiments would have different steerable members and different linkage arrangements to the above described embodiment, they would utilise similar lever arrangements to effect the turns. Likewise they would allow for correct shifting of body weight, and also like that of the above described wheeled embodiment they may utilise twist grip throttle controls.

The term "comprising" (and its grammatical variations) as used herein is used in the inclusive sense of "having" or "including" and not in the exclusive sense of "consisting only of.