| 摘要 |
PURPOSE: To surely keep torque transmission elements outside engagement thus preventing friction and vibration by making the torque transmission elements movable so as to release the torque transmission engagement due to the movement of an energization member against the energizing force of an energizing means. CONSTITUTION: When torque exceeds a predetermined value, a ball 18 rolls out of a torque transmission recess 16 and a force is applies to the left direction against the energizing force of a spring 21 to move a energization member 19 to a non-engagement position. The tangent of an angleα1 in this position is, however, smaller than the friction coefficient between the ball 18 and the energization member 19. Therefore, ball is held between the energization member 19 and an inner periphery 34 of an aperture 17, thus being kept in the non- engagement position. As a consequence, friction and vibration can be prevented since the ball 18 and the torque transmission recess 16 can be maintained outside engagement after clutch releasing.
|
