JPH0315566B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a one-wheel drive vehicle that can run with one of a pair of left and right wheels being driven by a power unit.

This type of one-wheel drive vehicle is disclosed, for example, in Japanese Unexamined Patent Publication No. 57-960. However, in any conventional one-wheel drive vehicle such as this, when one of the left and right wheels (usually the two rear wheels) is driven by the power unit, the driving force is due to the reaction force from the road surface. Gives turning force to the vehicle body. This tendency also occurs when the driving force changes to a reverse driving force during deceleration, although the road reaction force becomes in the opposite direction and reverses the turning force. As a result, a one-wheel drive vehicle tends to turn when accelerating or decelerating, and the steering wheel must be turned off to cancel the turning force while traveling straight, making it difficult to drive. Furthermore, when acceleration and deceleration are stopped in this state and the vehicle is shifted to constant speed driving, the vehicle body turns in a manner contrary to the driver's wishes in response to the turning angle of the steering wheel, which also poses a problem in that it is difficult to drive.

According to the present invention, if the driving wheels are suspended so that they are automatically steered by the driving force applied thereto, and the vehicle turning force is thereby canceled out, the vehicle can be controlled even when accelerating or decelerating as desired by the driver. The object of the present invention is to provide a one-wheel drive vehicle that embodies this idea, from the viewpoint that the above-mentioned problem can be solved by preventing the vehicle from turning in the opposite direction.

Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

1 and 2 show a one-wheel drive vehicle which is an embodiment of the present invention, in which 1 is a body frame, 2,
3 is the front two wheels, and 4 and 5 are the rear two wheels. The two front wheels 2 and 3 are suspended on the vehicle body frame 1 by normal suspension via swing arms 6 and 7, respectively, and can be steered by a steering mechanism (not shown). Eyes 8 and 9 are coaxially fixed on both sides of the rear part of the vehicle body frame 1, and a swing arm 10 for a rear wheel is vertically swingably supported on the vehicle body frame 1 via these eyes. One rear wheel 4 is directly rotatably supported on the free end of the swing arm 10, and a strut 11 is installed between the free end of the swing arm 10 and the vehicle body frame 1 to suspend the rear wheel 4 on the vehicle body frame 1. .

12 is a power unit for driving the other rear wheel 5, and the rear end of the power unit is connected to the link 13.
is connected to the free end of the swing arm 10 by. The link 13 has ball joints 13 at both ends.
A and 13b connect the free end of the swing arm 10 and the rear end of the power unit 12, and a strut 18 is installed between the rear end of the power unit 12 and the vehicle body frame 1 to suspend the rear wheel 5. Thus,
The rear wheel 5 is suspended so as to be movable not only in the vertical direction but also in the longitudinal direction through the swinging of the link 15.

As shown in FIGS. 3 and 4, the power unit 12 is a normal one consisting of a prime mover 14, a carburetor 15 including an air cleaner, a reduction gear 16, and an exhaust pipe 17. (not shown) is integrally coupled to the drive wheel 5. The connection of the link 13 and strut 18 to the rear end of the power unit 12 is made to the reduction gear 16.

The power unit 12 is suspended by a shackle 20 installed between the upper surface of the reduction gear 16 and the vehicle body frame 1, and elastically supported by a damper strut 21 in the longitudinal direction of the vehicle body. Shackle 20 is the fifth
As clearly shown in the figure, a pair of shackle plates 22 and 23 facing each other, a cross plate 24 connecting these plates, and a bush 2 inserted between the opposite ends of the shackle plates 22 and 23 are shown.
5 and 26, and pins 27 and 28 for pivotally supporting these bushes to the shackle plates 22 and 23. Each bush 25, 26 has an inner collar 25a, 26a and an outer collar 25b, 26b, respectively.
Rubber bushes 25c and 26c are vulcanized and bonded between them, and the outer collar 25b is attached to the vehicle body frame 1.
At the same time, the outer collar 26b is attached to a bracket 30 attached to the front end upper surface of the power unit 12, for example, the reducer 16.
The front end of the power unit 12 is suspended from the vehicle body frame 1 by the shackle 20. In addition, for this suspension, the shaft 20 is
As clearly shown in the figure, the shafts 27 and 28 at both ends of the shaft 20 are arranged so that the edge on the outside of the vehicle body (the left side in FIG. 7) is located further forward of the vehicle body (lower in FIG. 7) than the opposite edge. The brackets 2 are arranged at an angle so that the ends on the outside of the vehicle body are located forward of the ends on the inside of the vehicle body.
9 and 30 are fixed to the vehicle body frame 1 and the reduction gear 16, respectively.

As shown in FIG. 5, a through hole 24a is bored in the cross plate 24, and using this hole, one end of the damper strut 21 is attached to the cross plate 24 via a rubber bush 31 as shown in FIG. The damper strut 21 is a conventional one consisting of a shock absorber 32 and a spring 33 compressed between its cylinder and piston rod, and the other end of the damper strut 21 is attached to the vehicle body frame 1 as shown in FIG. In this way, the damper strut 21 can elastically receive the rotation of the shaft 20 accompanying the longitudinal movement of the power unit 12, and hence the driving wheels 5, and can elastically support the power unit 12 in the longitudinal direction of the vehicle body.

The operation of the one-wheel drive vehicle of the present invention configured as described above will be explained next.

The power of the prime mover 14 is transmitted to the drive wheels 5 via the reducer 16, and the vehicle can travel by rotating the drive wheels 5. While the vehicle is running at a constant speed, the damper strut 21 moves the shaft 20 as shown in FIGS. 7 and 8a.
In order to maintain the elastically supported state in the hanging position shown by the solid line in FIG. 8b, the drive wheels 5 are directed straight in the longitudinal direction of the vehicle as shown by the solid line in FIG. You can maintain your sexuality.

By the way, while the vehicle is accelerating, the power unit 12 receives a forward force (downward in FIG. 7) due to the driving force F applied to the drive wheels 5, as shown in FIG. 7, causing the damper strut 21 to retract. As a result, the power unit 12 is connected to the ball joints 13a, 1
Link 13 and pins 27, 28 rotating between 3b
While being guided by the shackle 20, which rotates from the solid line position in Figures 8a and 8b to the dashed-dotted line position, the vehicle body is displaced forward along with the drive wheel 5 from the solid line position in Figure 7 to the dashed-dotted line position. do. This displacement is due to the inclination of the shaft rotation shafts 27, 28.
Set the attachment point P of the shaft 20 on the power train side (the center point of the pin 28) to point P' in Figures 7 and 8 e _d
On the other hand, since the link 13 is sufficiently long, the displacement amount of the drive wheel 5 in the same direction is so small that it can be ignored, so the drive wheel 5 applies a driving force F to the vehicle. The vehicle is automatically steered to provide a slip angle that cancels out the turning force.

Also, even when the vehicle is decelerating, the wheels 5 are
Due to the driving force -F applied in the opposite direction, the power unit 12 and the driving wheels 5 are similarly displaced in the opposite direction from the position shown by the solid line in FIG. 7 to the position shown by the two-dot chain line.
As a result, point P moves to point P'' by e _b outside the vehicle body (7th
In this case as well, the drive wheel 5
is automatically steered to provide a slip angle that cancels out the turning force applied to the vehicle by driving force -F.

Therefore, in the one-wheel drive vehicle of the present invention, the turning force generated by the driving forces F and -F during acceleration and deceleration is canceled by the automatic steering of the drive wheels 5, and straight-line performance can be ensured even during acceleration and deceleration. Therefore, the one-wheel drive vehicle of the present invention does not turn against the driver's will while driving, does not require any steering operation to correct this, and prevents the vehicle from becoming difficult to drive. Can be done.

By the way, in the above embodiment, the shaft 2
Since the rotating shafts 27 and 28 at both ends of the power unit are parallel to each other, the angle θ of the power unit side rotating shaft 28 with respect to the vertical plane V in the vehicle width direction is as shown in FIG. 8a when the shaft 20 is not rotating. (while driving at constant speed)
When the shaft 20 rotates from the solid line position in FIG. 8a to the one-dot chain line position (during acceleration),
It remains unchanged even when rotating in the opposite direction (during deceleration).
Therefore, when the power unit 12 moves back and forth, the power unit tries to increase the angle θ to θ' during acceleration and decrease it to θ'' during deceleration, as shown in FIG. 7. This angle change is rubber bushing 25
It is necessary to absorb this by elastic deformation of c and 26c (see Fig. 5). Therefore, the rubber bushing 25c, 2
6c cannot be made harder than a certain level. Because of this,
The rubber bushes 25c and 26c are easily deformed by input from the road surface, and there is a concern that the automatic steering of the drive wheels 5, which is the original purpose of the present invention, may not be performed with high accuracy.

In order to solve this problem, the shackle 20 of the present invention can be configured as shown in FIG. 9. In this example, the mounting method of the shackle 20 (the rotational shafts 27, 28 are tilted in the longitudinal direction) is the same as in the example described above, but the mounting ends 22a, 23 of the shackle plates 22, 23 on the vehicle body side are made parallel. The pin 27 is bent so that the end on the outside of the vehicle body (left side in FIG. 9) is located above the end on the inside of the vehicle body.

Such a shackle 20 allows the power unit 1 to
The one-wheel drive vehicle of this example, in which the front ends of the two wheels are suspended from the body frame 1, functions in the same manner as the above-described example, and can prevent the vehicle from turning due to the wheel drive force even during acceleration and deceleration. During acceleration, the pins 27 and 28 are attached to the shaft 20 in the same manner as described above with reference to FIGS. 8a and 8b.
1 from the solid line position in Figures 10a and 10b around
It rotates to the dotted chain line position, but at this time the shaft 20
The angle .theta. of the power unit side rotation shaft 28 with respect to the vertical plane V in the vehicle width direction increases to .theta.' due to the vertical inclination of the vehicle body side rotation shaft 27 of the shaft 20. This angle increase corresponds to the angle increase from θ to θ' during acceleration described above with reference to FIG. 7, and the shaft 20 can be rotated without substantially elastically deforming the rubber bushes 25c, 26c. Further, the rotation of the shaft 20 in the opposite direction during deceleration is caused by changing the angle θ of the power unit side rotation shaft 28 with respect to the vertical plane V in the vehicle width direction based on the vertical inclination of the vehicle body side rotation shaft 27 of the shank 20. On the contrary, it decreases. This angle decrease also corresponds to the angle decrease θ→θ″ during deceleration described above with reference to FIG. 7, and the shaft 20 can be rotated without substantially elastically deforming the rubber bushes 25c, 26c.

Thus, in the one-wheel drive vehicle of this example, the rubber bushes 25c and 26c can be made hard;
It is possible to prevent these rubber bushings from deforming due to input from the road surface and from making the automatic steering of the driving wheels 5 inaccurate, which is the original objective of the present invention, and to fully achieve the objective of the present invention. can.

In order to completely match the angle change during acceleration/deceleration described above with reference to FIG. 10 with the angle change during acceleration/deceleration described above with reference to FIG. 7, the angle change θ'-θ in FIG. If the distance between the front end mount point P and the rear end mount point (ball joint 13b) of the unit 12 is S, then the positions of the shaft rotation shafts 27 and 28 are set so that θ-θ'= _ed /S. Of course, it is necessary to decide. In this case, there is no need for the rubber bushes 25c, 26c to undergo any elastic deformation during rotation of the shaft 20, and as long as vibrations from the prime mover 14 are not transmitted to the vehicle body frame 1, the rubber bushes 25c, 26c
26c can be made as hard as possible so that the above object of the invention is even more fully achieved.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view of the one-wheel drive vehicle of the present invention;
FIG. 2 is an enlarged perspective view of the main parts, and FIG. 3 is a side view showing the power unit of the one-wheel drive vehicle of the present invention.
FIG. 4 is a plan view of the same power unit, FIGS. 5 and 6 are enlarged sectional views and partially cutaway side views of the shackle and mount strut used in the one-wheel drive vehicle of the present invention, and FIG. 7 is a plan view of the power unit of the present invention. An explanatory diagram of drive wheel behavior during acceleration and deceleration of a wheel drive vehicle; FIG. 8a is a diagrammatic plan view for explaining the rotation of the shaft during vehicle acceleration;
FIG. 8b is a diagrammatic front view of the same, FIG. 9 is an enlarged sectional view of the shaft showing another example of the present invention, and FIG. 10a is a diagrammatic diagram for explaining the rotation of the shaft when the vehicle accelerates. The plan view, FIG. 10b, is also a diagrammatic front view thereof. 1...Vehicle frame, 2, 3...Front wheel, 4...Rear wheel,
5... Drive rear wheel, 6, 7... Front wheel swing arm,
8, 9... Eyeball, 10... Swing arm for rear wheel, 1
1, 18...Strut, 12...Power unit,
13...Link, 13a, 13b...Ball joint, 14...Motor, 15...Carburetor, 16...
Reducer, 17...Exhaust pipe, 20...Shackle, 21
...Dumper strut, 22, 23... Shackle plate, 24... Cross plate, 25, 26... Bush, 27... Shackle rotation shaft on the vehicle body side, 28
...shaft power unit side rotation shaft, 29...
Vehicle body side bracket, 30...Power unit side bracket.

Claims (1)

[Claims] 1. A one-wheel drive vehicle that can run by driving one of a pair of left and right wheels by a power unit,
The drive wheel is suspended so as to move back and forth by the driving force applied thereto, and the front end of the power unit is suspended from the vehicle body by a shackle. A one-wheel drive vehicle characterized by being inclined so that it is located forward of the inner end. 2. In a one-wheel drive vehicle that can run by driving one of the left and right wheels by a power unit,
The drive wheel is suspended so as to move back and forth by the driving force applied thereto, and the front end of the power unit is suspended from the vehicle body by a shackle. A single wheel, characterized in that the shaft is inclined so as to be located forward of the end on the inside, and the rotation axis of the shaft on the vehicle body side is inclined so that the end on the outside of the vehicle body is located above the end on the inside of the vehicle body. driving car.