| 摘要 |
792,894. Lever and nut gearing. GENERAL MOTORS CORPORATION. July 17, 1956 [Aug. 18, 1955], No. 22069/56. Class 80 (3). In a screw and nut mechanism in which the nut 12 engages the screw 10 through the intermediary of circulatory balls 18 the groove 20 of the screw is gradually cut deeper on each side of a central portion of constant depth which extends for at least 300 degrees of lead on each side of a transverse centre line so as to provide progressively increased play on either side of the central portion where there is substantially no play. |
