| 摘要 |
PURPOSE:To enable to manufacture a converting apparatus equivalent to a ball screw extremely easily, by forming a screw at either one or both of the inner surface and the outer surface of a ball bearing. CONSTITUTION:When a screw rod 1 is turned, a ball bearing 3 is moved linearly together with a holder 2 through partial thread engagement of the screw rod 1 and an inner ring 3a. Here, since the two screws held in partial thread engagement with each other have the same pitch but their lead angles are different from each other, the distance of linear motion of the holder 2 is slightly shorter than the pitch of the screws. However, the inner ring is turned relatively to an outer ring by an angle corresponding to the pitch difference, so that thread- engagement is made smooth. |
