| 摘要 |
891,036. Screw-and-nut gearing. GENERAL ELECTRIC CO. Ltd. March 7, 1960 [March 13, 1959], No. 8823/59. Class 80 (3) In screw-and-nut gearing comprising a screw 2 and non-rotatable nut 1 which is in two parts 3, 4, electromagnetic means are provided to effect relative movement between the parts 3, 4 in order to increase or decrease the slack between the screw and nut. The part 3 has a reduced end portion on which a collar 5 is slidably mounted and the part 4 has a collar 6 rigidly secured thereto in which is mounted an annular solenoid 7. Four symmetrically disposed brass bridging pieces 8 are attached to the end of the collar 6 and are engaged by four helical springs 11 which bear against an inside face of the collar 5. When the solenoid is not energized, the springs 11 push the parts 3, 4 apart to eliminate backlash. On energization of the solenoid 7, the springs 11 are compressed and the nut 1 is free to move easily relative to the screw 2. The arrangement may be modified so that slack is taken up by urging the parts 3 and 4 towards one another. In a further modification, the springs 11 are dispensed with and the thrust effected by the interaction of two solenoids arranged to attract or repel one another. |
