| 摘要 |
PROBLEM TO BE SOLVED: To obtain a structure of an expansion/contraction device which can effectively prevent the generation of noise by smoothly decelerating rotational speeds of an adjustment lever and a drive-side cam when switched to an unlock state from a lock state.SOLUTION: An elastic metal-plate made leaf spring 49 is relatively non-rotatably supported to a driven-side cam. Then, a tip of a deceleration arm 57 constituting the leaf spring 49 is located at a front side with respect to a lock release direction out of a periphery of an adjustment lever 25a which is relatively non-rotatably supported to a drive-side cam 29a. In a lock state of a cam device, a peripheral clearance 67 is formed in advance between a front side portion of the deceleration arm 57 and a front side face 68 of the adjustment lever 25a, the peripheral clearance 67 is set at zero in the middle of the switching to an unlock state from the lock state, the front side face 68 of the adjustment lever 25a is made to abut on the a tip side portion of the deceleration arm 57, and the deceleration arm 57 is warped and deformed.SELECTED DRAWING: Figure 5 |
