Clutch operation assisting device and power unit for straddle-type vehicle

摘要

A power unit for a motorcycle having a clutch operation assisting device. The clutch operation assisting device includes a push shaft, a bearing plate that supports the push shaft, and a first rotary plate rotatably supported on the bearing plate and connected to a clutch wire. The first rotary plate causes the push shaft to slide as it rotates and is gear-coupled to a second rotary plate. A spring unit that applies an assist force in a direction for disengaging a friction clutch is pin-coupled to the second rotary plate. The spring unit is supported on a mounting seat in a swingable manner and is installed such that, as viewed from the axial direction of the push shaft, the expansion/contraction direction of an auxiliary spring in the spring unit does not pass through a rotation center of the pressure plate.

主权项

1. A clutch operation assisting device provided in a clutch operating apparatus, the clutch operating apparatus including:
a friction clutch that has a pressure plate and a clutch spring for urging the pressure plate, and is arranged in a casing of a power unit; and an operating member that is connected to the friction clutch via a transmission member, and is manually operated against an urging force of the clutch spring when disengaging transmission of torque by the friction clutch, wherein the clutch operation assisting device is accommodated in the power unit casing and comprises: a slide member that rotatably supports the pressure plate and slides in a predetermined direction together with the pressure plate; a first rotary member that is connected to the transmission member, and rotates in accordance with the transmission member to cause the slide member to slide, the first rotary member having a hole formed therein in which a portion of the slide member is disposed, and including a gear portion; and an auxiliary elastic member for, when operating the operating member in a direction for disengaging the friction clutch, applying an urging force to the gear portion of the first rotary member while changing in its expansion/contraction direction during a period of time until the operating member reaches a disengage position where disengagement of the friction clutch is complete from a disengage start position where the operating member receives a reaction force of the clutch spring, the urging force causing the first rotary member to rotate in the direction for disengaging the friction clutch, wherein as viewed from a sliding direction of the slide member, the expansion/contraction direction of the auxiliary elastic member is offset from the rotation center of the pressure plate in both an operated position and a return position of the operating member.