| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a structure capable of making durability preferable by preventing the outer peripheral surface of a pressing block and the inner peripheral surface of a cylinder part from colliding with each other with great force. <P>SOLUTION: A small-diameter step part 27 is formed on the entire perimeter of an end on the outer end opening side of the cylinder part 20, on the outer peripheral surface of the pressing block 21a. A buffer ring 28, which is made of a material greater in internal loss than a material constituting the pressing block 21a and a casing 10 and which has an outside diameter as large as/larger than an outside diameter of the pressing block 21a, is externally fitted to the small-diameter step part 27. Even when the pressing block 21a is swung and displaced in the cylinder part 20 along with power transmission, an outer peripheral edge of a leading end of the pressing block 21a and the inner peripheral surface of the cylinder part 20 are prevented from colliding with each other with the strong force. <P>COPYRIGHT: (C)2013,JPO&INPIT |
