| 摘要 |
In a screw and nut driving device with low internal friction, e.g. a ball nut mechanism, irreversibility is effected in a simple and efficient manner when the nut (2) is rotatably driven and enclosed by an annular space in which a helical spring (7) is arranged in such a manner that its ends (8, 9) are acted upon by the driving force from the external driving source, thus that the spring can rotate freely in the space. When the external driving source is disconnected and the nut, due to axial load is subjected to a torque, the ends of the spring are acted upon thus that the spring is disformed to friction locking against a non-rotating surface, whereby the nut is prevented from rotation. |
