JPH0725351B2 - Motorcycle power transmission mechanism - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a power transmission mechanism for a motorcycle, particularly a high-power motorcycle.

[Prior art]

For transmission of power to the rear wheels of the motorcycle, as shown in FIG. 2, between the sprocket 2 on the engine 1 side and the sprocket 4 mounted on the rear wheel 3, an endless flexible member 5 such as a chain or a belt is provided. It is carried out by handing over.

[Problems to be Solved by the Invention]

In this case, the rear wheel 3 is driven by moving the endless flexible member 5 in the direction shown by the arrow in the drawing by the rotation of the sprocket 2 on the engine 1 side, and at this time, it is shown by the outlined arrow in the drawing. Since the moment acts, when the ground friction resistance of the rear wheel 3 is large and the output of the engine 1 is large, the so-called wheelie state in which the front wheel floats up is caused. This is very dangerous if the driver is inexperienced,
Making it difficult to drive a motorcycle. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a power transmission mechanism for a motorcycle that can transmit power to rear wheels without causing a wheelie state. is there.

[Means for Solving the Problems]

The present invention, however, is one in which an endless flexible member such as a chain or a belt is laid between the sprocket on the engine side and the sprocket provided on the rear wheel. It is characterized in that a rotation direction exchange member that is opposite to the rotation direction of both is provided so that the rotation direction of the forward rotation of the rear wheel is different from the rotation direction of the engine side sprocket. [Operation] According to the present invention, the rotation direction of the sprocket for driving the rear wheels and the endless flexible member is opposite to that of the conventional one.
The moment shown in the above-mentioned conventional example acts in the direction of increasing the ground contact force of the front wheels. [Embodiment] The present invention will be described in detail below based on the illustrated embodiment. The sprocket 2 connected to the engine 1 via a clutch and a speed change mechanism rotates in the direction indicated by the arrow in the figure by the engine 1. It is driven. The sprocket 4 provided on the rear wheel 3 and provided with the endless flexible member 5 such as a chain or a belt between the sprocket 2 on the engine 1 side and the sprocket 2 on the engine 1 side, the sprocket 4 with respect to the rear wheel 3 via the rotation direction conversion member 6. It is installed as The rotation direction changing member 6 in the illustrated example is the sprocket 4
A plurality of planetary gears supported by an internal gear 60 provided on the inner peripheral surface of the vehicle, a sun gear 61 fixed to the rear wheel 3, and a shaft 71 provided at the rear wheel support portion of the chassis 7 of the motorcycle. Each planetary gear 62, which is formed of a planetary mechanism including a gear 62 and meshes with both the sun gear 61 and the internal gear 60, rotates the rear wheel 3 in the direction opposite to the direction of rotation of the sprocket 4. In this motorcycle, however, the sprocket 2 on the engine 1 side, the endless flexible member 5, and the sprocket 4 on the rear wheel 3 side are rotated in the opposite direction to the normal one, and the sprocket 4 is rotated. The rotation direction conversion member 6 further converts the rotation direction to the reverse direction, and then the power is transmitted to the rear wheel 3. At this time, when the rear wheel 3 is driven, it acts on the sprocket 2 on the engine 1 side through the endless flexible member 5. The moment to act acts on the front wheel 9 side in the direction of touching the ground, as shown by the white arrow in the figure. Therefore, even if the rotation of the engine 1 is rapidly transmitted to the rear wheel 3, the wheelie state in which the front wheel 9 side floats up is not caused, and even an inexperienced person does not cause a dangerous state of wheelie. It is capable of driving. In the present embodiment, the planetary mechanism is shown as the rotation direction changing member 6 as described above, but the present invention is not limited to this, and the rotation of the sprocket 4 can be converted to the reverse direction and transmitted to the rear wheel 3. Anything is fine. Further, the motorcycles mentioned here include so-called three-wheeled motorcycles.

【The invention's effect】

As described above, in the present invention, between the rear wheel side sprocket and the rear wheel, the rotation direction changing member that reverses the rotation directions of the both is provided, and the rotation direction of the forward rotation of the rear wheel and the engine side sprocket are compared. Since the rotation direction is different, that is, in order to rotate the engine side sprocket, the rear wheel side sprocket and the endless flexible member in the opposite direction to the conventional one, the rear wheels are driven to move forward. The moment that acts on the sprocket on the engine side around the axle of the rear wheel when performing it acts in the direction to increase the ground contact force of the front wheel and does not cause the wheelie state where the front wheel floats up, which is dangerous for untrained people. The safety is improved because the wheelie state disappears.

[Brief description of drawings]

FIG. 1 is a schematic front view of an embodiment of the present invention, and FIG. 2 is a schematic front view of a conventional example, in which 1 is an engine, 2 and 3 are sprockets, 3 is a rear wheel, 5 is an endless flexible member, Reference numeral 6 denotes a rotation direction conversion member.

Claims (1)

[Claims] 1. An endless flexible member such as a chain or a belt is laid between an engine side sprocket and a sprocket provided on a rear wheel, wherein both the rear wheel side sprocket and the rear wheel are provided. Is provided with a rotation direction conversion member that reverses the rotation direction of the rear wheel so that the rotation direction of forward rotation of the rear wheel is different from the rotation direction of the engine side sprocket.