| 摘要 |
<p>The structure is arranged such that between the supporting portion le of the casing 1 and the collar portion 2s of the rotor 2, there is displaced the second elastic member 4 for pressing the collar portion in the axial direction of the driving shaft 10, that the pressing force of the second elastic member is greater than the frictional force to be generated between the driving shaft and the first elastic member 5 when the driving shaft moves in the back-and-forth direction of the axial direction, and that the rotor is prevented from moving forward by the pressing force of the second elastic member when the driving shaft moves in the forward direction to go out of the rotor 2. <IMAGE></p> |
