Patent GB-190721281-A (GB)
Title: Improvements relating to Variable-speed Hubs for Cycles.
Inventor: SAUNDERS MONTAGU
Filed: 1907-09-25
Granted: 1908-08-27
Abstract: 21,281. Saunders, M. Sept. 25. Driving-mechanism; brakes.-In a three-speed gear for cycles of the kind employing two epicyclic trains, planetpinions P, P<1> are mounted upon the opposite faces of a single carrier E, which is provided between the pinions with one part of a clutch co-operating with a corresponding clutch part L on the hub shell. The carrier may be recessed to receive the clutch pawls retained in position by a washer K and by pegs working in holes in the carrier, or the ring L upon the hub may carry the pawls to engage ratchet teeth upon the carrier. As shown, the ring L with a right-handed screw-thread abuts against the internally-toothed ring D of the high-speed train, which has a left-handed thread. In the gear shown in Fig. 1, the sun-pinion 0 is arranged to be locked at M to the carrier, and in its outer position to a fixed part R ; the second sun-wheel O<1>, the movement of which under the action of a spring V is limited by a device such as a flange N upon the carrier, has ratchet teeth &c. to engage similar teeth upon a fixed part R', so that, should the machine be wheeled backwards when the high gear is in operation, the sun-wheel O<1> is free to turn in that direction. The cross-pin T may be operated by a control rod W, return and buffer springs X, X<1> being provided. In a modified construction, a fixed clutch is arranged between the sun-pinions, as described in Specification No. 22,211, A.D. 1906, the low - speed sun - pinion being adapted to be clutched to the sprocket-wheel, while the teeth of the fixed clutch are arranged on the slant to allow of the high-speed sun-pinion turning backwards. In this case, the cross-pin of one sun-pinion bears against an enlarged portion of the control rod, while a distance-sleeve &c. upon a smaller part of the rod enables the second cross-pin to be kept in its proper relative position by the return spring arranged within the axle. According to the Provisional Specification, the internal wheel of the highspeed train may drive the hub through a one-way clutch, and if the sun-pinion of this train is free to turn forwardly but not backwardly on the low and normal speeds, the internal wheel may be used to actuate a back-pedalling hub brake. Also, in lieu of the clutch between the carrier and the hub, a similar connexion may be provided between the carrier and the internal wheel of the high-speed train, and in this case, if the sun-piuion cannot turn backwardly and the connexion between the internal wheel and the brake-actuating part is capable of being put out of action by the backward rotation of the road wheel, the gear is such as to permit the machine being wheeled backwards without the brake being applied. For severing the connexion between the internal wheel and the brake-actuating part, a backward-acting clutch may be provided between these members, while one part of the driving-clutch between the internal wheel and the hub is mounted on a separate member capable of a certain amount of angular movement against the action of a spring.