| 摘要 |
914,610. Screw-and-nut gearing. ANDERSON CO. Jan. 20, 1960 [Feb. 4, 1959], No. 2048/60. Class 80 (3). [Also in Group XXXIV] The threads of a single or multi-threaded screw 10, Fig. 1, are engaged by toroidal portions 19 on rollers 17 mounted in equallyspaced openings in a cage 25 fixed to a " nut " casing 41, the rollers 17 being held against the screw by a freely-rotatable ring 20. The ring 20 has opposed raceways engaging the rollers whereby the ring is axially located. As shown, the screw 10 has a triple start thread engaged by three rollers 17, and the cage 25 is secured in a housing 34 surrounded by a resilient pad 40 in the flanged casing 41. Rotation of the screw 10 thus causes axial movement of the casing 41 to operate, for example, a vehicle window, the ring 20 then rotating idly. In modifications wherein the screw is axially moved by rotation of the " nut ", the cage 25 is fixed directly in the hub of a driving gear or pulley. In one such form, Fig. 3 (not shown), the hub is rotatably mounted and is shaped to form a housing corresponding to the housing 34; in another form, Fig. 7, the cage 25 itself is supported by ball-bearings 68 in a fixed frame 60 and is extended to carry the pulley or gear 80. In a further modification a single-thread irreversible screw 53, Fig. 5, is engaged by rollers 55 which are distributed around the screw in axially staggered formation. The rollers 55 are held against the screw 53 by a freely rotatable ring 56 axially located by inturned flanges which engage certain of the rollers, there being preferably an even number (four, as shown) of rollers. |
