GB573579A - Improvements in or relating to variable speed gearing - Google Patents

Abstract

573,579. Variable - speed gearing. OWEN, C. A. Nov. 15, 1943, No. 19038. [Class 80 (ii)] A variable-speed gear comprises a driving- shaft 4 which drives a parallel but laterally displaced driven shaft 16 through one of a number of pairs of pinions 10, 11 which are carried by a carrier member 7. The pinions 10 are of different diameters and are all engaged by a gear 5 on the driving-shaft. The pinions 11 are driven by their respective pinions 10 through one-way clutches 13, shown as the helical spring type, which assist in the engagement of these pinions one at a time with an internally toothed gear 17 on the driven shaft 16, when the carrier 7 is rotated to different positions to give different speed ratios, the diameters of the pinions 11 being arranged so that the crests of their teeth lie on a circle concentric with the shaft 4. The position of the carrier 7 is controlled by detents 20 on arms 18 which engage in holes on the periphery of the carrier. The arms 18 are actuated by cams 25 either manually, through lever 31 and gears 33, 34, 38, 41, or automatically, according to the'load, by utilising a spring coupling 63, 64, 65 on the driven shaft 16 and a double train of gears to a differential 74 adapted to operate the cams 25. A changeover lever 55 operates clutches 37, 40 and 44, 46 for manual or automatic operation. In a modified form the carrier 7 is rotatably mounted upon an eccentric on the driven shaft, the shaft 4 including a universal joint to permit the eccentric movement of the carrier. Alternatively, the driven shaft may be moved eccentrically and include a universal joint. A " neutral " position of the carrier may be provided, also a '' reverse " by driving one of the pinions 11 in an opposite direction.