GB242901A - Improvements in variable speed friction gearing - Google Patents

Abstract

242,901. Gill, C. H. June 4, 1925. Variable-speed friction gearing comprises pulleys on parallel shafts connected by a friction ring encircling both shafts. Cone discs 17 are screwed to a driving-shaft 16 by threads 80, Fig. 5, of opposite hand so as to tend to separate. The transmission ring 36 makes connection with a like pulley comprising cones 28 which, however, tend to come together. The whole gear is controlled automatically by a spring 91 acting on pivoted levers 88, or the spring may be assisted by manual control. When the driving pulley 17 is opened right out, the ring 36 is lifted clear of the pulleys to disconnect the drive by a roller 45, Fig. 1, on a lever 48. At the same time a spring-pressed catch roller 40 snaps over a shoulder 23, and so holds the pulley cones 17 separated. In the application to a vehicle shown in Figs. 1 and 2, two such variable gears are used to drive road-wheel axles 25 independently. The shaft 16 is driven through a worm pair 14, 15 from an engine shaft 13, no main clutch or differential being necessary. Reversed driving is effected from the shaft 13 through a second worm pair 49, 50 and shaft 51. The shaft 51 is geared to each of the axles 25 by a ring 58 passing over two non-variable grooved pulleys 52, 53. The drive cannot pass back from a pulley 53 to a ring 58. The reverse is brought in by a clutch 60, which is double, the other set of teeth and reversing-train 78 being brought into action when coasting, using the engine as a brake. When the clutch 60 is in neutral, the rings 58 are raised out of gear by levers 71,. Fig. 1.