| 摘要 |
PURPOSE:To urge an oscillating member by smaller urging means by forming a floating space for loosely rotating urging means interposed between a support member and the oscillating member when the oscillating member is oscillated within a fixed range with respect to the support member. CONSTITUTION:A movable member 2 is supported on a support member 1 through a backward and forward oscillating member 3. The member 3 comprises a driving arm 4 and a posture retaining arm 5 which are parallel to each other. The first urging device 7 is interposed between the above arm 5 and the support member 1, and the second urging device 8 is interposed between the arm 4 and the movable member 2. In this case, the urging devices 7, 8 are respectively provided with urging means 12, 13 comprising a square shaft 9, a square cylinder 10 loosely fitted to the shaft, and an elastic body 11 interposed between the shaft 9 and the cylinder 10. In square cylinder support holes 19, 22 of coupling plates 17, 20 through which the square cylinder 10 pierces, there are provided floating spaces 19a, 22a for permitting the square shaft 10 to loosely rotate within a designated range. |
