JPH0442235B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a swing arm control mechanism for a motorcycle.

In a motorcycle, for example, a shaft drive type motorcycle, the front end of a swing arm is pivotally supported on the body frame, the rear wheel is held at the rear end of the swing arm, and the shaft drive disposed inside the swing arm is supported. The engine output is transmitted to the rear wheels through the

Generally speaking, when a large driving force is suddenly applied to such a motorcycle, such as during acceleration, the rear end of the swing arm moves significantly downward relative to the body frame, causing the rear end of the body frame to flip up. On the other hand, if the driving force suddenly decreases, such as during braking, the rear end of the vehicle body frame may sink significantly, which is an unfavorable phenomenon in terms of driving operation.

The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a swing arm control mechanism that suppresses undesirable behavior of the swing arm with respect to the vehicle body frame due to changes in the magnitude of the driving force. shall be.

In order to achieve this object, the present invention includes a torque arm swingably provided on the vehicle body frame, a tip of the torque arm and a swing arm connected via a torque rod, and a base end of the torque arm connected to a swing arm via a torque rod. is coupled to a mechanism that generates a torque as a reaction force of the driving force of the engine when the driving force generated by the engine is transmitted to the driving wheels, and the torque arm and the torque rod provide the swing arm with the The structure is such that it provides a rocking force proportional to the driving force of the rear wheels.

With this configuration, the swing arm is given a force proportional to the rear wheel drive force in the direction of suppressing its undesirable behavior.
This prevents the rear end of the body frame from lifting up or sinking.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention applied to a shaft drive type motorcycle will be described below in detail with reference to the drawings.

In FIG. 1, the front end of a swing arm 2 is pivotally supported by a pin 3 on a vehicle body frame 1, and a rear wheel 4 is held at the rear end of the swing arm 2. The swing arm 2 is hollow and has a shaft drive rotatably disposed therein.
The shaft drive and the rear wheel 4 are interlocked by a bevel gear (not shown). car body frame 1
is equipped with a transmission 5 in addition to an engine (not shown), and the output of the engine is transmitted from the transmission 5 to the rear wheels 4 via a universal joint 6 (internal configuration not shown) and the shaft drive. It's becoming like that.

A torque arm 7 is swingably held in the transmission 5 as will be described later. The front end of a torque rod 9 is pivotally supported at the tip of the torque arm 7 by a pin 8, and the rear end of the torque rod 9 is connected to an arm 11 projecting upward from the middle part of the swing arm 2 by a pin 10. It is pivotally supported.
Note that 12 in FIG. 1 is a rear wheel suspension system.

The torque arm 7 is adapted to receive a swinging force (torque) proportional to the rear wheel driving force, and the torque generating mechanism will be explained below with reference to FIGS. 2 and 3. A sun gear 14 is integrated into the drive shaft (final output shaft) 13 of the transmission 5, while the base end of the torque arm 7 is annular and has an internal gear 15 formed therein. This internal gear 15 is disposed surrounding the sun gear 14 so that its center coincides with the center of the sun gear 14, and between the two gears 14 and 15 there is a space between the two gears 14 and 15. A plurality of planetary gears 16 that mesh with each other are interposed. In this way, the torque arm 7 is able to swing freely around the center of the sun gear 14, that is, the drive shaft 13.
Further, the plurality of planetary gears 16 are each rotatably held by a carrier 17.
A drive bevel gear 19 that is integrated with the shaft 18 that is more protruding meshes with a driven bevel gear 21 that is integrated with the shaft 20 that is connected to the universal joint 6. Of course, the axial center of the shaft 18 coincides with the axial center of the drive shaft 13.

Next, the operation of the above configuration will be explained. As shown in FIG. 1, since the torque arm 7 is connected to the swing arm 2 via the torque rod 9, free rotational movement about the drive shaft 13 is restricted. In this state, now
When the drive shaft 13 rotates clockwise in FIG. 3 together with the sun gear 14 integrally attached to the drive shaft 13 and the motorcycle attempts to accelerate forward, a plurality of gears mesh with the sun gear 14. The planetary gear 16 rotates counterclockwise and runs clockwise in FIG. 3 on the internal gear 15 of the torque arm 7. This movement of the plurality of planetary gears 16 causes the carrier 17 to rotate clockwise in FIG. 3. In this state, the rotational driving force transmitted from the drive shaft 13 to the carrier 17 is transmitted to the rear wheel 4 via the shaft 18, bevel gears 19, 21, shaft 20, and universal joint 6.

When a large driving force is suddenly applied, such as during acceleration, the rear end of the swing arm 2 moves significantly downward relative to the vehicle body frame 1, causing the rear end of the vehicle body frame 1 to flip up. At this time, a force acts on the torque arm 7 in the counterclockwise direction (in the direction of arrow A) in FIG. 3 due to the increased rotational torque of the plurality of planetary gears 16 meshing with the internal gear 15. Therefore, this force pulls up the swing arm 2 via the torque rod 9 and the arm 11, and as a result, the downward movement of the rear end of the swing arm 2 is prevented. The force acting in the counterclockwise direction in FIG. 3 from the torque arm 7 to the swing arm 2 is proportional to the rear wheel drive force.

Conversely, when decelerating by applying the brakes, the driver tightens the throttle to lower the engine speed, but due to the inertia caused by the previously maintained traveling speed, the rear wheels 4 are forced from the universal joint 6 to the shaft 2.
0, a state is reached in which rotational torque is applied to the engine via the bevel gears 21 and 19. As a result, the carrier 17 attempts to rotate in the counterclockwise direction in FIG. 3 due to the opposite action to that described above, so that the torque arm 7 receives a force in the clockwise direction (in the direction of arrow B) in FIG. act. This force is transmitted to the swing arm 2 via the torque rod 9 and the arm 11.
As a result, the rear end of the vehicle body frame 1 is prevented from sinking during deceleration.

Although the embodiments have been described above, the present invention can be similarly applied to chain-driven motorcycles. Depending on the vehicle model (due to differences in the mounting position of the pin 3, which is the center of swing of the swing arm 2), the rear end of the vehicle body frame 1 may sink during acceleration (the rear end of the vehicle body frame 1 may sink during deceleration). However, in this case, the swinging of the torque arm 7 can be prevented by, for example, protruding the arm 11 downward as shown in FIG. The swinging direction of the swing arm 2 with respect to the direction may be opposite to that in the embodiment. Further, when disposing the drive shaft 13 and the torque arm 7 at separate positions, for example, the torque arm 7
It is directly held swingably on the vehicle body frame 1 without intervening, and an external gear is provided on the gear corresponding to the internal gear 15, and an external gear is also formed at the base end of the torque arm 7. Both external gears may be made to interlock with each other. Of course, the drive shaft 13, the shaft 18, and the torque arm 7 can be linked to any one of the sun gear 14, the internal gear 15, and the carrier 17, that is, the drive shaft 13 can be connected to any one of the components 14, 15, and 17. Coupling any one of the shafts 18 with the component 1
4, 15, and 7, and the torque arm 7 can be linked to the other one.

The present invention is a swing arm control mechanism for a motorcycle having the configuration and operation as described above,
Since the reaction force of the driving force acting on the power transmission system that transmits the driving force generated by the engine to the driving wheels is extracted by the control torque generation mechanism and transmitted to the swing arm via the torque rod, the driving force of the driving wheels is It is possible to suppress undesirable behavior of the swing arm during acceleration and deceleration of the motorcycle due to sudden changes in torque, thereby improving driving operability.

This action is performed directly by the reaction force of the drive torque that drives the drive wheels, so it is highly responsive to sudden changes in drive torque, and engine braking is effective when a sudden downshift is performed during deceleration. This will be very effective in situations such as sudden start-up, etc.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the latter half of a motorcycle to which the present invention is applied, and FIGS. 2 and 3 show a mechanism for giving the torque arm a swinging force proportional to the rear wheel drive force. 2 is a sectional view taken along the line of FIG. 3, and FIG. 3 is a sectional view taken along the line of FIG. 1... Vehicle body frame, 2... Swing arm,
4... Rear wheel, 7... Torque arm, 9... Torque rod, 13... Drive shaft, 14... Sun gear, 15... Internal gear, 16... Planetary gear,
17...Carrier.

Claims (1)

[Scope of Claims] 1. In a motorcycle in which a front end of a swing arm is pivotally supported on a body frame, and a rear wheel held by the rear end of the swing arm is driven, a torque arm is swung on the body frame. The distal end of the torque arm is movably connected to the swing arm via a torque rod, and the proximal end of the torque arm is connected to the drive force of the engine when transmitting the driving force generated by the engine to the drive wheels. The swing arm is coupled to a mechanism that generates a torque as a reaction force of the force, and the torque arm and the torque rod are configured to apply a swinging force proportional to the driving force of the rear wheel to the swing arm. Motorcycle swing arm control mechanism. 2. In claim 1, the mechanism for generating a torque as a reaction force of the engine's driving force comprises a drive shaft receiving the driving force from the engine, a sun gear provided on the drive shaft, and the sun gear. an internal gear provided at the end of the torque arm on the swing center side so as to surround the torque arm, a plurality of planetary gears interposed between the sun gear and the internal gear, and the plurality of planetary gears. and a carrier rotatably holding the wheel, and the driving force is transmitted to the rear wheels via the carrier.