| 摘要 |
1,005,962. Screw and nut gearing. ROTAX Ltd. April 1, 1963 [April 5, 1962], No. 13205/62. Heading F2Q. Associated with a ball typo screw and nut mechanism is a member 13, having limited angular freedom relative to the nut 4 and a helical rib engaging the groove 3 in the screw 1, so arranged that during relative rotation of the screw and nut in one direction the rib moves freely in the groove 3, but during rotation in the opposite direction the rib binds in the groove, thus resisting rotation, e.g. to prevent a load on a lifting apparatus from causing the screw to rotate. The nut 4, housing members 5, 10, and a spacer ring 7, are fast with a body 2 of a lifting apparatus and the member 13 has end clearance 17 in the housing 10. When the shaft is rotated so as to move to the right the member 13 will be driven against a thrust bearing 14 so that it binds on the screw 1 and prevents further rotation of the latter. A release device (Fig. 2, not shown) enables the member 13 to be turned slightly to take up the clearance 17 and allow free rotation of the screw 1 in the previously resisted direction. |
