| 摘要 |
884,914. Screw and nut gearing. BRITISH OXYGEN CO. Ltd. June 23, 1960 [June 26, 1959], No. 22028/59. Class 80 (3). In a mechanism wherein a rotatable screw 11 moving a body 10 is engaged by two nuts 12, 13 pressed apart by a spring 34 to take up backlash, the nuts 12, 13 are mounted with rotational and axial clearance in respective housings 14, 15 secured to the body 10. Each nut 12, 13 has a portion 16, 25 of rectangular or other non-circular section engaging with clearance a corresponding recess 17, 26 in the respective housing 14, 15. Moreover, each nut 12, 13 has an attached member 18, 31 which is a sliding fit on the screw 11 and has projections 18<SP>x</SP>, 31x engaging guideways 33, so that the members 18, 31 support the screw against sagging. The nuts 12 and 13 are respectively shorter than and longer than their housings 14 and 15 to provide axial clearances (shown exaggerated). Lateral clearances may also be provided to accommodate misalignment. The screw thrust is transmitted to the housing 14 either, in one direction, through the nut 12 and member 18 or, in the other direction, through the nut 13, spring 34 and washers 24, 28. The screw mechanism is applicable to machine tools and flame cutting machines. |
