GB2382806A

GB2382806A - Three-wheeled vehicle

Info

Publication number: GB2382806A
Application number: GB0228044A
Authority: GB
Inventors: Jonathan Mark Parsons
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-12-04
Filing date: 2002-12-02
Publication date: 2003-06-11
Anticipated expiration: 2022-12-02
Also published as: GB2382806B; GB0228044D0

Abstract

The vehicle has all three wheels 1-3 in line with steering by front and middle or rear wheels. The middle wheel 2 is driven by a motor or by pedals with optionally a chain drive to the rear wheel 3. This three-wheel arrangement improves vehicle stability, without increasing width, or preventing the vehicle from being leaned into corners. Total cornering and power drive traction are increased. Additional steering is provided at the middle wheel e.g. by hub steering or by a link from front handlebars, which enables the vehicle to change direction, e.g. go around a corner, even when the vehicle is leaned over. Skidding will be reduced; even if the front steered wheel loses traction when cornering, turning effort will still be provided by the middle steered wheel 2. The middle wheel 2 can have its own suspension or the wheels by linked by swinging arms 5,8.

Description

THREE-WHEELED VEHICLE This invention relates to a three-wheeled vehicle, whereby all three wheels are in a line, with steering by front wheel and middle wheel. The design is similar to conventional two wheeled vehicles, which have a steered front wheel and powered rear wheel, but with the additional middle steered wheel, which also may be powered. A mechanical arrangement provides the middle wheel with combined steering, suspension, brake, drive from a power unit to it and drive from it to the rear wheel. An alternative arrangement uses a steered rear (third) wheel instead of the steered middle wheel.

Two wheeled vehicles are well-known forms of transportation, often known as bicycles, motorcycles or bikes, powered by various power sources, including human, or petrol engine. Two wheeled vehicles are normally steered by the front wheel and powered by the rear wheel. When changing direction the bike can be leaned into the comer to prevent it from toppling over. Two wheeled vehicles can become unstable when one of the wheels breaks traction, e. g. skids. Skids may occur as a result of many circumstances, e. g. poor road conditions, applying too much power to the driven wheel, or excessive cornering speed.

To improve stability more wheels can be added, e. g. wheels to the side can be added, but then the ability to lean over is compromised and the overall width of the bike increases, preventing the bike from passing through narrow gaps and increasing aerodynamic drag.

According to the present invention, there is provided a vehicle with three wheels in a line; with steered front (first) wheel and middle (second) wheel ; powered drive to the second and third wheels; and brakes on one, two or three of the wheels. The middle (second) wheel has steering, suspension, brake, drive from a power unit to it and drive from it to another wheel. An alternative arrangement uses a steered rear (third) wheel instead of the steered middle wheel.

Steering may be by means of a frame-mounted handlebar connected to the front wheel steering, with a linkage to the second wheel steering. The linkage may be by means of a pivoted rod, cable, hydraulic system, or electrical system. The steering of the front wheel and second wheel may be by means of a fork steering head, or wheel hub steering. The forks may be telescopic stanchion and leg arrangement, leading link, trailing link, or other motorcycle fork arrangement. When turning the handlebar, steering linkages turn the front and middle wheels together in the same directions, to enable the vehicle to lean over and follow a curved path. The linkage is arranged to turn the second wheel less than the front wheel. This invention has middle wheel steering by means of a vertical, or near vertical pivot at the top and bottom of a wheel pivot support mounting. The vertical pivot connects to a wheel bearing support containing wheel bearing and wheel shaft. The pivot is in line with the middle wheel drive CV joint and the wheel centre line. In an alternative arrangement a steered third wheel is used, instead of the steered middle wheel and when turning the handlebar, steering linkages turn the front and rear wheels in opposite directions.

The suspension movement of front wheel may be similar to a conventional two-wheeled vehicle; the suspension movement of the second wheel may be similar to the front, or the rear wheel of a conventional two-wheeled vehicle e. g. swinging arm ; the suspension movement of the third wheel may be located by means of a swinging arm pivoted about the second wheel's axis, or pivoted about a mounting on the frame. This arrangement allows each wheel to move up and down, over bumps, independently. This invention has middle (second) and rear wheel suspension by means of a parallel, or near parallel pair of swinging arms, one above the other, connecting at one end by pivot joints supported in a frame and at the other end by pivot joints attached to the top and bottom of a wheel pivot support mounting. The swinging arms can be positioned above and below, or to the side of the power unit. A suspension linkage provides spring damper control of the swinging arms. The suspension linkages can be repositioned to allow changes in rates of spring compression of either wheel (the middle or rear wheel). Also the suspension linkages can be repositioned to make springing of one wheel dependent upon the other, or visa versa, thus compression on one would alter the spring preload on the other. The ends of the swinging arms proved a pivot point for another pair of swinging arms, one on top of the other. The second pair of swing arms provide a mounting for an additional driven in-line wheel (rear wheel). This arrangement allows each wheel to move up and down, over bumps, independently.

Power drive to one, two or three of the wheels may be by means of chain and sprockets, or hub mounted hydraulic, or electric motor. This invention has wheel drive by means of a chain and sprocket drive. The power unit and rear wheel having one sprocket, the middle wheel having two, one connected by chain to the power unit sprocket, the other connected by a second chain to the rear wheel sprocket. The rear wheel sprocket is coaxial with the rear wheel and drives the rear wheel, directly of via a coupling. The middle wheel sprocket is attached to a shaft, which rotate in bearing which are perpendicular to the vertical and forward/aft axis of the vehicle. The middle wheel sprocket shaft is connected to the wheel shaft via a CV type connector, or other device to allow shaft misalignment, thus allowing drive to be maintained even if the wheel shaft's axis is at an angle relative to the sprocket shaft's axis. The chains remains in line with the vehicle axis, even when the middle wheel is steered. The position of the CV joint is in line with the wheel centre line and steering centre line.

The swinging arm movement radii can be the same as that of the drive sprocket to wheel sprocket movement radii, this prevent changes in chain tension.

Middle wheel braking is by means of a brake calliper fixed to the wheel bearing support and acting against a disc, which is fixed, to the wheel shaft.

In order to power the vehicle an engine may be fitted between the front and second wheel, above or to the side of the second and rear wheel, or in one or more of the wheels.

This three-wheeled vehicle invention improves vehicle stability, without increasing width, or preventing the vehicle from leaning into comers. Total cornering and power drive traction are increased. Additional steering is provided at the middle wheel, which enables the vehicle to change direction, e. g. go around a comer, even when the vehicle is leaned over. Skidding will be reduced ; even if the front steered wheel loses traction when cornering, turning effort will still be provided by the middle steered wheel; when accelerating traction is no longer dependent on only one wheel; when braking traction is spread across three rather than two wheels.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing in which: Figure 1 shows a view on the side of the three-wheel vehicle, showing the three-wheel layout and basic principles of the suspension arrangement to allow the vehicle to go over bumps. Referring to the drawing the three-wheeled vehicle comprises a front or first wheel 1, a second wheel 2, and a third or rear wheel 3. Locating and providing steering and suspension for the front wheel is a suspension fork 4. Locating the second wheel and allowing it to move up and down is a swinging arm 5, which pivots about a frame mounted spindle 6, and is sprung by spring damper 7. Locating the rear wheel and allowing it to move up and down is swinging arm 8, which pivots about the second wheel spindle 9, and is sprung by spring damper 10. Frame 11 provides a mounting for the front suspension fork, second wheel swinging arm, power unit, rider and other necessary parts of a motor vehicle.

Figure 2 shows the wheel movement when the second wheel is on a bump.

Figure 3 shows the wheel movement when the third wheel is on a bump.

Figure 4 shows a view on the side of a three-wheel vehicle, showing the mechanical arrangement incorporating the parallel swinging arm arrangement. Referring to the drawing: Locating the middle wheel 2 and allowing it to move up and down is a pair of swinging arms 21 and 22, which pivots about a frame 11 mounted spindles 20, and is sprung by spring damper 24. Locating the rear wheel 3 and allowing it to move up and down is a pair of swinging arms 27 and 28, which pivots about the ends of the swinging arm pair 21 and 22, and is sprung by spring damper 23, via linkage 25 and 26. Linkage 25 and 26 provide control of the spring damper 23 to allow the movement of the middle wheel to pre-load the spring. The middle and rear wheel are driven by a chain drive arrangement 29.

Figure 5 shows a view looking down on the wheels with the wheels in the straight-ahead position. Other vehicle parts are omitted for clarity.

Figure 6 shows a view looking down on the wheels with the wheels in the steer right position. Other vehicle parts are omitted for clarity. Steering for the front wheel may be by a conventional bicycle steering head, or a hub steering with the steering pivot within the wheel hub. Steering for the middle wheel is as shown in figure 8,9, 10 and 11.

Wheel drive is by means of a chain and sprocket drive 29. The power unit and rear wheel having one sprocket, the middle wheel having two, one connected by chain to the power unit sprocket, the other connected by a second chain to the rear wheel sprocket.

When the middle wheel is steered the drive sprocket remain at right angle to the vehicle axis.

Figure 6a shows the alternative front and rear wheel steering layout. Steering for the rear wheel may be by a hub steering, with cables linked to the handlebars used to steer the wheel.

Figure 7 shows a view looking down on the wheels with the wheels in the steer left position. Other vehicle parts are omitted for clarity.

Figure 7a shows the alternative front and rear wheel steering layout.

Figure 8 shows the handlebar steering arrangement, looking down on the wheels.

Steering is shown in the straight-ahead position. Handle bar 12 turns the front forks 4 and front wheel 1 about pivot 13. Handle bar 12 connect to rod 14. Rod 14 has a pivot at either end and connects to lever arm 15. Lever arm 15 steers the middle wheel 2 about pivot 16.

Figure 9 shows the handlebar steering arrangement, looking down on the wheels, with the steering in the steer left position.

Figure 10 shows the mechanism to steer the middle wheel, which also allows the middle wheel to move under suspension movement. Lever 15 turns rod 16, which turns link arms 18 and 17, which turns the wheel bearing support 19 to steers the middle wheel 2.

Rod 16 turns in a steering head mounting hole in frame 11. Scissor link arms 18 and 17 have pivots at either end allowing them to move up and down without adjusting the steering position. The middle wheel 2 steers about a pivot within the wheel (see figure 11).

Figure 11 shows a section through the middle wheel. The wheel rim 30 is fastened to the wheel shaft 34 by wheel nut 33. The disc brake 31 is fixed to the wheel shaft 34. The wheel shaft 34 is supported by the wheel bearing 32, which is supported by the wheel bearing support 39. The wheel bearing support 39 is attached to the wheel pivot support mounting 40 by a pair of pivot pins (or bolts) 38. The wheel bearing support 39 can pivot vertically or, near vertically and is controlled by an arm connected to steering link 17 (see figure 10). The wheel pivot support mounting 40 is attached to the swinging arms 21,22, 27 and 28 by a pair of pivot pins (or bolts) 41 (see figure 4). Sprockets 42 and 43 are driven by the power unit and supply power to the rear wheel. Sprockets 42 and 43 are attached to a sprocket shaft 44, which is supported by sprocket bearing 45, fixed in the wheel pivot support mounting 40. The sprocket shaft 44 drives a cv joint 37, which drives the wheel drive shaft 36, which drives and is attached to the wheel shaft by splined disc 35. The cv joint allows misalignment of the sprocket shaft 44 and the wheel drive shaft 36.

Claims

CLAIMS 1. A three-wheel vehicle with the wheels in a line and steering by two of the wheels.
2. A three-wheel vehicle as claimed in claim 1 wherein the middle (second) and rear wheels are driven.
3. A three-wheel vehicle as claimed in claim I wherein all three wheels can be braked.
4. A three-wheel vehicle as claimed in claim I wherein each wheel is able to move up and down independently to the others.
5. A three-wheel vehicle as claimed in claim I wherein the front wheel is located and allowed to move up and down by a front suspension fork.
6. A three-wheel vehicle as claimed in claim 1 wherein the middle (second) wheel is located and allowed to move up and down by a swinging arm, which pivots from the vehicle frame.
7. A three-wheel vehicle as claimed in claim I wherein the third wheel is located and allowed to move up and down by a swinging arm, which pivots about the middle (second) wheel spindle.
8. A three-wheel vehicle as claimed in claim I wherein the middle wheel is steered by wheel hub steering.
9. A three-wheel vehicle as claimed in claim I wherein the third wheel is steered by hub rear wheel steering.
10. A three-wheel vehicle as claimed in claim 1 wherein the handlebar used to steer the front wheel is connected by means of a rod to the middle wheel steering mechanism.

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11. A three-wheel vehicle as claimed in claim 1 wherein scissor link arms connected to a steering head, allow the middle (second) wheel to be steered even when the middle (second) wheel may be moving up and down under suspension movement.
12. A three wheel vehicle as claimed in claim I wherein an engine to propel the vehicle is located between the front and middle (second) wheel, above or to the side of the middle (second) and rear wheel, or in one or more of the wheels.
13. A three-wheel vehicle as claimed in claim 1 wherein a chain drives the middle (second) and rear wheels.
14. A three-wheel vehicle as claimed in claim 1 wherein the middle wheel has combined steering, suspension, brake, drive from a power unit to it and drive from it to the rear wheel.
15. A three-wheel vehicle as claimed in claim 1 wherein the middle wheel's suspension is by means of a parallel, or near parallel pair of swinging arms, one above the other, connecting at one end by pivot joints supported in a frame and at the other end by pivot joints attached to the top and bottom of a wheel pivot support mounting.
16. A three-wheel vehicle as claimed in claim I wherein the rear wheel's suspension is by means of a parallel, or near parallel pair of swinging arms, one above the other.
17. A three-wheel vehicle as claimed in claim I wherein suspension linkages can be repositioned to allow changes in rates of spring compression of either wheel (the middle or rear wheel).
18. A three-wheel vehicle as claimed in claim 1 wherein middle wheel steering is by means of a pair of vertical, or near vertical pivots within the wheel hub and on the vertical centre- line of the wheel.

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19. A three-wheel vehicle as claimed in claim I wherein a middle wheel pivot support mounting is within the wheel hub and provides a location for the drive bearing, support for the wheel bearing support and linkage between the swinging arms for both middle and rear wheel.
20. A three-wheel vehicle as claimed in claim 1 wherein a wheel bearing support provides support for the wheel bearing, brake and wheel, and allows the wheel to be steered.
21. A three-wheel vehicle substantially as described herein with reference to Figures 1,2, 3,4, 5,6, 7,8, 9, 10 and 11 of the accompanying drawing.

21. A three-wheel vehicle as claimed in claim 1 wherein the middle wheel's drive incorporates a CV joint, or other device to allow shaft misalignment, positioned in line with the vertical centre-line of the wheel and middle wheel steering pivot centre-line.

22. A three-wheel vehicle substantially as described herein with reference to Figures 1, 2,3, 4, 5,6, 7,8, 9,10 and 11 of the accompanying drawing.

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1. A three-wheel vehicle with the wheels in a line and steering by two of the wheels wherein the middle (second) and rear wheels are driven.

2. A three-wheel vehicle as claimed in claim 1 wherein all three wheels can be braked.

3. A three-wheel vehicle as claimed in claim 1 wherein each wheel is able to move up and down independently to the others.

4. A three-wheel vehicle as claimed in claim 1 wherein the front wheel is located and allowed to move up and down by a front suspension fork.

5. A three-wheel vehicle as claimed in claim 1 wherein the middle (second) wheel is located and allowed to move up and down by a swinging arm, which pivots from the vehicle frame.

6. A three-wheel vehicle as claimed in claim 1 wherein the third wheel is located and allowed to move up and down by a swinging arm, which pivots about the middle (second) wheel spindle.

7. A three-wheel vehicle as claimed in claim I wherein the middle wheel is steered by wheel hub steering.

8. A three-wheel vehicle as claimed in claim 1 wherein the third wheel is steered by hub rear wheel steering.

9. A three-wheel vehicle as claimed in claim 1 wherein the handlebar used to steer the front wheel is connected by means of a rod to the middle wheel steering mechanism.

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10. A three-wheel vehicle as claimed in claim 1 wherein scissor link arms connected to a steering head, allow the middle (second) wheel to be steered even when the middle (second) wheel may be moving up and down under suspension movement.

11. A three wheel vehicle as claimed in claim 1 wherein an engine to propel the vehicle is located between the front and middle (second) wheel, above or to the side of the middle (second) and rear wheel, or in one or more of the wheels.

12. A three-wheel vehicle as claimed in claim 1 wherein a chain drives the middle (second) and rear wheels.

13. A three-wheel vehicle as claimed in claim 1 wherein the middle wheel has combined steering, suspension, brake, drive from a power unit to it and drive from it to the rear wheel.

14. A three-wheel vehicle as claimed in claim 1 wherein the middle wheel's suspension is by means of a parallel, or near parallel pair of swinging arms, one above the other, connecting at one end by pivot joints supported in a frame and at the other end by pivot joints attached to the top and bottom of a wheel pivot support mounting.

15. A three-wheel vehicle as claimed in claim 1 wherein the rear wheel's suspension is by means of a parallel, or near parallel pair of swinging arms, one above the other.

16. A three-wheel vehicle as claimed in claim 1 wherein suspension linkages can be repositioned to allow changes in rates of spring compression of either wheel (the middle or

17. A three-wheel vehicle as claimed in claim 1 wherein middle wheel steering is by means of a pair of vertical, or near vertical pivots within the wheel hub and on the vertical centre- line of the wheel.

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18. A three-wheel vehicle as claimed in claim 1 wherein a middle wheel pivot support mounting is within the wheel hub and provides a location for the drive bearing, support for the wheel bearing support and linkage between the swinging arms for both middle and rear wheel.

19. A three-wheel vehicle as claimed in claim 1 wherein a wheel bearing support provides support for the wheel bearing, brake and wheel, and allows the wheel to be steered.

20. A three-wheel vehicle as claimed in claim 1 wherein the middle wheel's drive incorporates a CV joint, or other device to allow shaft misalignment, positioned in line with the vertical centre-line of the wheel and middle wheel steering pivot centre-line.