JPS6146783A - Power transmission gear for 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 A0 OBJECTS OF THE INVENTION (1) Field of Industrial Application The present invention relates to a power transmission device for vehicles, particularly two- and three-wheeled vehicles.

(2) Conventional technology Conventionally, a swing arm with a drive wheel mounted on a vehicle body frame is swingably mounted, and the drive wheel is linked to an output member of a power plant via a wrap-around transmission mechanism. In a vehicle such as a two-wheeled vehicle, the swing shaft fulcrum of the swing arm and the rotation center of the drive wheel of the wrap-around transmission mechanism are arranged concentrically, and when the swing arm swings, the swing-axis fulcrum of the wrap-around transmission mechanism rotates. A device in which the endless transmission band does not loosen is known, for example, from Japanese Utility Model Publication No. 54-28759.

(3) Problems to be Solved by the Invention However, in the conventional system, the pivot shaft of the swing arm and the drive system of the winding transmission mechanism are configured separately, so the swing arm pivot point and the winding transmission mechanism are separated. Not only is it difficult to precisely align the drive wheels of the mechanism on a concentric axis, but the pivot part of the swing arm, which is subject to a relatively large load such as an impact load, must be made sturdy, resulting in an increase in weight. There was a problem.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to easily align the pivot point of the swing arm and the rotation center of the drive wheel of the wrap-around transmission mechanism precisely and concentrically, and to swing the swing arm by the pivot shaft. It is an object of the present invention to provide a power transmission device for a vehicle in which the strength of a pivot portion of an arm is increased, and the hanger portion of a power plant can be supported by the pivot shaft, thereby reducing the number of parts and greatly simplifying the overall configuration. This is the purpose.

B0 Structure of the Invention (1) Means for Solving the Problems According to the present invention, in order to achieve the above object, a pivot shaft is horizontally fixed to the vehicle body frame, and the pivot shaft is mounted on the vehicle body frame. A swing arm that supports the hanger portion of the power plant and also supports the travel drive wheel is pivotably supported, and furthermore, the output shaft of the power plant is disposed on an axis concentric with the pivot shaft, and the output shaft is A drive wheel of a wrap transmission mechanism that is interlocked with the travel drive wheel is fixed to the shaft.

(2) Effect According to the above configuration, the pivot point of the swing arm that supports the travel drive wheel and the rotation center of the drive wheel of the wrap-around transmission mechanism that drives the wheel coincide on the concentric axis, and the swing arm swings. Even when the arm swings, the endless transmission band of the wrap-around transmission mechanism does not loosen.
The pivot shaft of the swing arm significantly increases the strength of the pivot portion of the swing arm, and furthermore, the pivot shaft can be used as a support member for the power plant to the vehicle body frame.

(3) Example A preferred example of the present invention will be described below with reference to the drawings.

First, in FIG. 1, a power plant P is mounted on a body frame 1 of a motorcycle at a central portion between a front wheel TVf and a rear wheel Wr. As usual, the front wheel Wf is suspended on a front fork 3 that is steerably supported by a head pipe 2 of the body frame 1, and the rear wheel IF'r is mounted on a pivot shaft 13, which will be described later, at the rear of the body frame 1. The rear fork 4 is pivoted on the rear part of the swing arm, that is, the rear fork 4, which is pivotally supported so as to be able to swing up and down.
It is suspended from the vehicle body frame 1 via a beamer cushion 5 in the middle.

The power plant P is composed of an engine E, a clutch C, and a transmission M as one unit, and inside a transmission case 6 at the bottom thereof, a crankshaft 7 of the engine E, a main shaft 8 and a countershaft 9 of the transmission M are installed. are rotatably supported in parallel to each other, the crankshaft 7 and the main shaft 8 are interlocked via a clutch C as usual, and the main shaft 8 and the countershaft 9 are interlocked via a gear group 10. Ru.

Since the transmission system from the crankshaft 7 to the countershaft 9 has a conventionally known structure, detailed explanation will be omitted.

A final drive gear 11 is provided at one end of the countershaft 9.
is fixed, and the gear 11 is always meshed with an output gear 12, which will be described later.

A hanger portion 6a is integrally extended rearward at the left and right center portions of the rear end of the transmission case 6, and a hollow pivot shaft 13 substantially parallel to the counter shaft 9 is passed through the hanger portion 6a. There is. The pivot shaft 13 has both ends connected to the left and right frame pipes 11 .of the vehicle body frame 1 . It is horizontally fixed to the bottom 7'L/-)iZ'1r' which is integral with lr.

Therefore, the bearing portion 6a of the transmission case 6 is supported by the vehicle body frame 1 via the pivot shaft 13.

At both ends of the pivot shaft 13, the front end pressure of the swing arm, that is, the rear fork 4, and the right pivot portion 41, 4 are provided.
r is rotatably supported via bearings 14 and 15, and the rear fork 4 can swing up and down about the pivot shaft 13.

A rearwardly protruding housing 6b is integrally formed on the left side of the rear end of the transmission case 6, and a cover unit 25 is attached to the open side surface of the housing 6b. The pivot shaft 13 crosses the nozzle 6b and passes through the cover unit 25. Inside the housing 6b,
An output shaft 18 is rotatably supported via bearings 16 and 17, the pivot shaft 13 passes through a shaft hole 19 of the output shaft 18, and a collar 20 is provided between the pivot shaft 13 and the shaft hole 19. be mediated. The output shaft 18 has the output gear 1
2 is integrally formed, and its output gear 12 meshes with the final drive gear 11 on the countershaft 9.

The output shaft 18 and the output gear 12 are coaxial with the pivot shaft 13 and can rotate around the central axis LL.

One end of the output shaft 18 projects outward from the transmission case 6, and a driving sprocket 21 is fixed to the projecting outer end 18.2. This drive sprocket 21 is connected to the rear wheel 111"r via an endless transmission chain 22.
The driving sprocket 21 and the endless transmission chain 22 are interlocked with a driven sprocket 23 (Fig. 1) fixed to the
The driven sprocket 23 constitutes a winding transmission mechanism.

A rear cushion 5 that connects the vehicle body frame 1 and the rear fork 4 is disposed immediately behind the hanger portion 6a, avoiding the accommodation housing 6b of the output shaft 18.

Next, the operation of this embodiment will be explained. When the motorcycle runs now, the rear fork 4 swings up and down about the center axis LL of the pivot shaft 13 while expanding and contracting the rear cushion 5 together with the rear wheel Wr.

Further, the power output from the carrot E is transmitted to the countershaft 9 of the transmission M via the crankshaft 7, shift latch C, and transmission gear group 10. The rotation of the counter shaft 9 is controlled by the final drive gear 11 and the output gear 12.
is transmitted to the drive sprocket 21 via the transmission chain 22 and the driven sprocket 23 to the rear wheel W.
transmitted to γ. Since the drive sprocket 21 rotates around the center axis LL of the pivot shaft 13, even if the rear fork 4 swings up and down around the pivot shaft 13, the transmission chain 22 of the wrap-around transmission mechanism will not loosen. does not occur.

In the above embodiment, the rear wheel W mounted on the rear fork 4 is
Although the present invention has been described in the case where the present invention is applied to the power transmission of
For example, it goes without saying that the present invention can also be applied to transmitting power to the driving front wheels.

C0 Effects of the Invention As described above, according to the present invention, a pivot shaft is horizontally fixed to the vehicle body frame, and the hanger portion of the power plant mounted on the vehicle body frame is supported on this pivot shaft, and the traveling drive wheels are also supported on the pivot shaft. The supported swing arm is swingably supported, and the output shaft of the power unit is disposed on a shaft concentric with the pivot shaft, and a drive wheel of a wrap-around transmission mechanism is connected to the output shaft, which is linked to the travel drive wheel. Since this is fixed, the endless transmission band of the wrap-around transmission device does not loosen when the swing frame swings, thereby increasing the power transmission efficiency and improving the durability of the device.

Further, since the pivot shaft connects the left and right pivot parts of the swing arm and supports the front part of the power plant, the pivot shaft can reinforce the pivot part of the swing arm, which is subject to a relatively large load. The weight of the pivot portion can be reduced, and the number of parts for the support portion of the power unit can be reduced, making it possible to simplify the structure and reduce costs.

In addition, the pivot shaft supports the engine part of the power plant, and the drive wheel of the wrap-around transmission mechanism is disposed on the pivot shaft, so that the pivot point of the swing arm and the rotation center of the drive wheel are It can be easily aligned with the central axis of the pivot shaft, improving ease of assembly.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a side view of a motorcycle equipped with the device of the present invention, and FIG. 2 is a cross-sectional view of the device of the present invention. D... Wrap transmission mechanism, P... Power plant, Wγ
...Rear wheel as a driving wheel

Claims (1)

[Claims] A pivot shaft is horizontally fixed to the vehicle body frame, and a swing arm that supports a hanger portion of a power plant mounted on the vehicle body frame and pivotally supports a travel drive wheel is swingably supported on the pivot shaft, Further, an output shaft of the power plant is disposed on a concentric axis with the pivot shaft,
A power transmission device for a vehicle, characterized in that a drive wheel of a wrap-around transmission mechanism that is interlocked with the running drive wheel is fixed to the output shaft.