GB480421A - Improvements in variable speed transmission gear - Google Patents

Abstract

480,421. Variable - speed gearing; toothed wheels. SANTON, E. July 12, 1937, No. 19252. [Classes 80 (i) and 80 (ii)] Variable speeds are transmitted between driving and driven toothed cones 2, 3 by an axially displaceable idler 8, having one or more rows of teeth 9 which can yield radially against springs 11 and centrifugal force, so as to mesh correctly with the cones in any position. Adjacent rows of teeth 9 may be of the same pitch and angularly staggered, or of different pitch, and are carried in discs separated by partitions 16, and either independent of each other, or clamped together by bolts 17, which may also serve to limit outward movement of the teeth. The teeth of the cones and idler may be helical, and the cones carry additional half-length teeth 12, with chamfered ends 13. To prevent jamming, fixed side-plates 34 press the teeth 9 inwardly just before meshing takes place. In order to provide for disconnection of the drive, thus allowing the gear to be used in a motor-vehicle without a mainclutch, the teeth 9 in the engaging zone of either or both cones, can be retracted inwards by depressing a cam-plate 38, Fig. 6, which turns one or two levers 36, contacting pins 39, projecting axially from the gear-teeth 9 through radial slots 40 in the side-walls of the idler 8. The levers 36 have a pin-and-slot mounting 42 on the idler and slide along a fixed pivotshaft 37. The cam-plate 38 may be operated by the vehicle brake-pedal 49, so as to disconnect the gear when the brakes are applied, or it may be manually operated, directly by a pedal 46, or through an electromagnet. A catch is provided for retaining the cam-plate in the operative position. The idler 8 slides on or with a non-rotatable shaft 7, and may be operated by a fork on the end of a screwthreaded parallel shaft, turned by a nut formed as a worm-wheel, engaging a worm on the shaft of a reversible electric motor. Alternatively the idler shaft 7 itself may be screw-threaded and carry an internally threaded toothed bevel-wheel, engaging a bevel-wheel to which is secured a friction bevel-wheel adapted to be engaged alternately by a pair of axially shiftable friction discs splined on the shaft of one of the main cones 2, 3.