GB261124A - Improvements in variable speed gear for motor bicycles and the like - Google Patents

Abstract

261,124. Sturmey-Archer Gears, Ltd., and Wilkie, W. Aug. 27, 1925. Variable-speed gearing suitable for motor-cycles yielding four speeds comprises four pairs of spur wheels, one pair d, e being fast on a driven sleeve c, a second pair f, g being mounted fast and one loose on a lag shaft b, a third pair i, h being mounted one fast and one loose on the main or driving shaft a, and a pair j, k on the lay shaft both adapted to be loose or keyed thereto. In the arrangement shown in Fig. 1, the changes are effected by moving two double-ended claw clutches l, m on the main and lay shafts respectively. The gear i has a long boss j<1> upon which the clutch sleeve m is slidably splined. This sleeve is adapted to engage alternatively with clutch teeth b<1> upon the shaft b and teeth g<1> on the face of the gear g. The sleeve m also carries clutch dogs m<1> which pass through holes in the gear into engagement with clutch slots k' in the gear k. The double clutch l is splined on the shaft a and can engage alternatively with clutch faces on the gears e, h. For the first or lowest speed, the clutch m engages the gear k when the train a, i, k, m, b, f, d is operative. For the second speed, the clutch m is returned to the position shown, and the clutch h engages the gear h. The active train is a, l, h, j, m, b, f, d. To effect the third speed, the clutch m is engaged with the gear g. The train is then a, l, h, j, m, g, e. The fourth speed is a direct drive through train a, l e. In a modified arrangement shown in Fig. 4, the same four changes are effected by moving the gears h, j, which remain mutually in mesh and carry the appropriate dog clutch members. Control is effected by forks n<1>, n<2>, Fig. 3, which slide on a fixed guide o and are operated by a hand-actuated disc cam p, which is locked in gear positions by a spring bolt r, Fig. 4.