| 摘要 |
PURPOSE:To prevent a half nut from being parted from a screw shaft by forming a projection placed at a slight gap from a press contact plane to the half nut. CONSTITUTION:The half nut 30 (hereinafter a nut) provided to a free end of an arm member 26 is arranged between the screw shaft 5 and a support plate 1 and the projection 30a placed with a slight gap (g) from a guide path 1a being the press contact plane provided to the support plate 1 is formed to the said nut 30. Further, a semi-cylindrical regulating section 30b regulating the shaking of the nut 30 in a direction along with the turning center axis of the screw shaft 5 in sliding contact with the screw shaft 5 is formed to the nut 30, and the nut 30, i.e., an arm member 26 is moved smoothly along the screw shaft 5 without being shaken in the direction of the turning axis of the screw shaft 5 by providing the regulation section 30b.
|
