GB190703414A - Improvements in and relating to Variable Speed Epicyclic Gears - Google Patents

Abstract

3414. Rudge-Whitworth, Ltd., and Pountney, F. Feb. 11. Driving-mechanism.-In a variable-speed gear, suitable for a cycle hub, the lowest speed is a direct drive, a second speed is obtained through an epicyclic train, and each additional speed is obtained by throwing in a further epicyclic train. In one form a ratchet clutch c, Fig. 1, communicates the direct drive from the driving-sleeve b to the hub. The sleeve b carries spindles d of the planet-pinions g of the first gear train. The pinions g mesh with a sun-pinion e loose on a fixed axle f and with an annulus h connected to the huh by the ratchet clutch j. The first train drives the hub through the clutch when the pinion e is held against rotation. The annulus is connected to and drives the spindles k of the planet-pinions o of the second gear train. The pinions o mesh with a loose sun-pinion m and with an annulus p secured to the hub ; or, if a fourth speed is required, the annulus is connected to the hub by a ratchet clutch and also to the spindles of the planet-pinions of a third gear train. For the third speed, the pinion m is held against rotation as well as the pinion e. The pinions e, m are connected by sleeves to rings of ratchet teeth q, s, respectively, of different lengths, and capable of being engaged in succession by a sliding spring plunger u, Fig. 1. In a modification the plunger u is replaced by a pivoted pawl v, Fig. 3. In a further modification, the teeth q, s are of equal length, as shown in Fig. 7, and the plunger u is provided with two engaging parts s<1>, q<1>, the latter being movable relatively to the former and normally held protruded beyond the former by a spring. In a second form of gear, shown in Figs. 9 and 10, the speed-variations are effected by sliding the sun-pinions longitudinally. The second speed is effected by sliding the right-hand pinion to the right until saw teeth 2, Fig. 10, engage teeth 3 on the axle f. The low speed is effected by causing both pinions to rotate together by dogs 4, 5. For the third speed the sun-pinions are locked together and to the axle f. The various combinations can be effected by a rod 6 which carries a fast cotter 7 engaging the pinion m and a loose cotter 8 engaging the pinion e. The cotters are separated by a light spring 9 and the rod 6 is thrust to the left by a strong spring 13. Sliding sun-pinion combinations as shown in Fig. 21 may also be employed.