JPS59149876A - Bogie car - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] It is related to vehicles.

There is a vehicle for driving on rough terrain that has a final reduction mechanism installed on the rear axle to which a pair of left and right rear wheels are attached, and transmits the rotation of the ennon to this final reduction mechanism via a chain or drive shaft to drive the rear wheels. . This type of vehicle sometimes uses relatively small-diameter, ultra-low-pressure tires, but when the rear wheels have a small diameter, the final reduction mechanism provided on the rear wheel axle comes closer to the road surface. Therefore, when driving on a highly undulating road surface, or when riding while straddling a convex part of the road surface with both rear wheels stuck in the ruts, the lower part of the final reduction mechanism tends to hit the convex part of the road surface, and the final reduction mechanism tends to hit the convex part of the road surface. There was a risk of damaging the deceleration mechanism.

On the other hand, in conventional vehicles, the chain and drive shaft that transmit the rotation of the engine to the final reduction gear were arranged parallel to the longitudinal central axis of the vehicle body.

Therefore, the lateral position of the final reduction mechanism is determined by the width of the engine. For example, in a vehicle where the driver is seated astride the seat above the engine, the width of the engine is narrower, so this mechanism must be placed closer to the center of the vehicle body. For this reason, there is a problem in that the position of the final reduction mechanism is far from both rear wheels, and the final reduction mechanism is more likely to hit a convex portion of the road surface.

The present invention has been made in view of the above circumstances, and its entire purpose is to provide a vehicle for driving on rough terrain, in which the final reduction mechanism provided on the rear axle is less likely to be hit by protrusions on the road surface or obstacles.

In order to achieve this object, the present invention provides a vehicle for driving on rough terrain having a rear axle to which a pair of left and right rear wheels are attached, a final reduction mechanism attached to the rear axle, and an engine mounted in front of the rear axle. In the vehicle, the rotation of the engine is transmitted to the final reduction mechanism via a drive shaft, and the drive shaft is arranged at an angle with respect to the center axis of the vehicle body so that its rear end is deviated to the side of the vehicle body relative to its front end. The final reduction mechanism is arranged so as to be close to one of the rear wheels.

The present invention will be described in detail below based on the illustrated embodiments.

FIG. 1 is a side view showing an embodiment of the present invention, FIG. 2 is a partially omitted plan view, and FIG. 3 is a partially sectional plan view of the main parts. In these figures, reference numeral 10 indicates a vehicle body frame. The vehicle body frame 10 includes a steering shaft cylinder 12 located at its front end, a main pipe 14 extending rearward from the steering shaft cylinder 12, and a pair of left and right downcomers 16 (16a) extending rearward and diagonally downward from the steering shaft cylinder 12. , ], 6 b) and main manager 1
Seat rail fl 18 extending rearward and diagonally downward from 4
(18a.

18b), seat rails 20 (20a, 20b) extending rearward from the seat pillar pipe 18, and seat rails 2
The rear tubes 22 (22a, 22
b). The rear end of the downcomer pipe 16 and the lower ends of the seat pillar pipe 18 and the rear pipe 22 are connected to the bracket 24 (
24a, 24b).

26 is a rear arm, which includes a front cylinder 28, a rear cylinder 30, and a left part 3.
2 and a cloth tube 34 to form a substantially trapezoidal shape, and the front tube 28 is connected to the bracket 24 snake pot shaft 36 (36a).
, 36b). As a result of B, is the rear arm 26 Bi? It becomes possible to swing up and down about the cut shaft 36. The rear axle 38 is attached to the rear cylinder 30 with a bearing 39 (39a,
39b), and on both left and right ends of the rear axle 38 are rear wheels 4 having wide and small diameter ultra-low pressure tires.
0 (4, Oa, 40 b) is attached. Note that the left cloth tubes 32 and 34 are positioned obliquely with respect to the central axis in the longitudinal direction of the vehicle body so that their rear ends are deviated to the side of the vehicle body relative to their front ends. In other words, the distance between the left cloth tubes 32 and 34 is wider at the rear.

A final reduction mechanism 42 is provided at the joint between the left portion 32 and the rear cylinder 34.
is provided. This mechanism 42 includes a flange 44 fixed to the left end of the rear cylinder 34, an inner cover 46 fixed to this seven flange 44, a large reduction gear 48 rotatably held on the inner cover 46, and a large reduction gear 48 rotatably held on the inner cover 46. ? The spline cylinder 50 is fitted and fixed to the spline cylinder 50i, a cover 52 that rotatably holds the spline cylinder 50i and covers the gear 48, and a pinion shaft 56 on which a pinion 54 meshing with the gear 48 is formed. The rear axle 38 includes a spline cylinder 50 and a bearing 39a.
, 39b, the inner cylinder 58 serves as a spacer for keeping the inner ring spacing between the brake discs 60 and 39b at an appropriate distance. 62f: Penetrates each. Between the stepped portion 63 of the rear axle 38 and the nut 64, the inner ring of the bearing 39a, the inner cylinder 58, the inner ring of the bearing 39b, and the disk 62 are held in order, and the spline cylinder 50? A spring 62 is splined to the rear axle 38.

A footwear unit 64 is attached between the rear arm 26 and the main pipe 14, and this unit 64 gives the rear arm 26 a tendency to return clockwise in FIG.

Reference numeral 66 denotes an engine, which is mounted in a space surrounded by the main pipe 14, the downcomer pipe 16, and the seat pillar pipe 18. The engine 66 is equipped with a constant mesh transmission, and the rotation of the subshaft 68 (FIG. 3) of this transmission is transmitted to the bevel gear 72 rotatably held on the engine output shaft 70.
4. This output shaft 70 is arranged parallel to the central axis of the vehicle body in the longitudinal direction.

A cam cylinder 76 splined on the output shaft 70 is pressed against a cam surface 80 of the bevel gear 72 by a spring 78.
This cam cylinder 76 and bevel gear 72 are connected to a cylindrical end face cam mechanism 82.
form. This cam mechanism 82 prevents sudden acceleration of the rear wheel 40.
It has the effect of absorbing the shock caused by deceleration. A drive shaft 84 is disposed within the left portion 32. The front end of this drive shaft 84 is connected to the output shaft 70 by a Cardan joint 86,
The rear end is connected to the pinion shaft 56 by a gear type joint 88 (6). Note that, like the left portion 32, this drive shaft 84 is arranged obliquely with respect to the vehicle body center axis so that the rear end thereof is deviated to the side of the vehicle body from the front end.

In Fig. 1, 90 is a front fork, 92 is a front wheel, 94 is a steering wheel, 96 is a rear fender, 98 is a driver's seat,
100 is a fuel tank, and 102 is a battery. battery 1
02 is attached to the main frame 10 so as to be located above the cloth tube 34, and is designed to balance the weight of the drive shaft 84, final reduction mechanism 42, etc. disposed on the left front 32 side with the weight of this battery 102. It has become.

Next, the operation of this embodiment will be explained. The rotation of the engine 66 is controlled by the subshaft 68, the output shaft 70, the cardan joint 86, and the drive shaft 8.
4. The signal is transmitted to the large reduction gear 48 through the gear type joint 88, the pinion shaft 56, and the pinion 54, and is further transmitted to the rear axle 38 and rear wheel 40 through the spline cylinder 50. When the rear wheel 40 rides on a convex portion of the road surface while the vehicle is running, the impact is absorbed by the deformation of the tire and the upward rotation of the rear arm 26. Considering the case where only the intervening rear wheel 40a rides on a convex part of the road surface, the center of the rear axle 38 moves upward by half the amount of upward movement of the rear wheel 40a. If the final reduction mechanism 42 is moved closer to the rear wheel 40a, the amount of upward movement of the final reduction mechanism 42 will also increase.

Therefore, the lower end of the final reduction mechanism 42 is less likely to hit the road surface protrusion.

FIG. 4 is a sectional view showing the vicinity of a final reduction gear mechanism 42A of another embodiment. In the embodiment of B, case 52A rear arm 2
6A rear cylinder 30A, large reduction gear 4.8A i
The side cover 4.6 is engaged with the binion 54 from the outside of the vehicle body.
A is installed from the rear wheel 40a side. Therefore, by removing the rear wheel 40a1 side cover 46A, the gear 4.8
A can be attached and detached, improving maintainability. In addition, since the large-diameter large reduction gear 48A is deviated more to the side of the vehicle body than in the embodiment shown in FIGS. The diameter part is also larger than the rear wheel 4.
0a, and the effects of the present invention become even more remarkable. Furthermore, since the rear axle 38A'i is supported, the distance between the bearings 39Aa and 39Ab is widened.

This is advantageous in terms of the rigidity of the suspension system against the bending moment that the rear wheels 40 apply to the rear axle 38A.

In this embodiment, the rear wheel shaft 38A is inserted from the side opposite to the large reduction gear 48A of the rear cylinder 34, and the rear wheel 4. Since the Oa side is made thinner than the rear wheel 40B side,
Gear 48 of rear wheel shaft 38A and each rear wheel 40a, 4.
It is possible to reduce the difference in the torsion spring coefficient between the torsion spring coefficient and Ob, and it is possible to suppress the imbalance in the transmitted torque.

In each of the above embodiments, the rear wheel 40 is connected to the rear arm 26°26A.
However, the present invention also includes a structure in which the rear wheel shaft is rigidly supported on the vehicle body frame 10. In the present invention, the lower end of the final reduction mechanism is connected to the engine 66.
This is particularly effective in the case of objects that protrude downward from the bottom at all times or during rocking. Further, the present invention can be applied not only to three-wheeled vehicles but also to four-wheeled vehicles having two front wheels, and of course includes this case as well.

As described above, the present invention drives the rear wheels using the shaft drive mechanism (9), and deviates the rear end of this drive shaft to the side of the vehicle body to bring the final reduction mechanism closer to one of the rear wheels. .

As a result, the road surface convex portion is less likely to hit the final reduction mechanism, thereby preventing damage to this mechanism.

[Brief explanation of the drawing]

Fig. 1 is a side view of one embodiment of the present invention, Fig. 2 is a partially omitted plan view, Fig. 3 is a partially enlarged plan sectional view, and Fig. 4 is another embodiment. FIG. 38.38A...Rear wheel axle, 40...Rear wheel, 42°4
, 2 A... Final reduction mechanism, 66... Engine, 84
...Drive shaft. Patent Applicant Yamaha Motor Co., Ltd. Agent Patent Attorney Yama 1) Yu Moon (10)

Claims (1)

[Claims] In a rough terrain vehicle having a rear axle to which a pair of left and right rear wheels are attached, a final reduction mechanism attached to the rear axle body, and an engine mounted in front of the rear axle, the rotation of the engine is driven. The transmission is transmitted to the final reduction mechanism via a shaft, and the drive shaft is disposed obliquely with respect to the vehicle body center axis so that its rear end is deviated to the side of the vehicle body relative to its front end, and the final reduction mechanism is A vehicle for driving on rough terrain characterized by having one rear wheel close to the other.