Patent GB-190400856-A (GB)
Title: Improvements in Variable Gear for Cycles and Motor Vehicles.
Inventor: CALLENDAR HUGH LONGBOURNE
IPC: F16H3/10
Filed: 1904-01-13
Granted: 1904-12-08
Abstract: 856. Callendar, H. L. Jan. 13. Driving - mechanism, variable - speed, for cycles and motor vehicles. In the arrangement shown in Fig. 1, free-wheel sprocket - wheels T<2>, T<3> are mounted on the hub of the sunpinion S and the wheel hub b respectively. Planet-pinions P are carried by a frame driven from the engine, and gear with the pinion S and with an internally-toothed ring R fixed to the hub b. Slip-ring clutches S<1>, S<2>, such as are described in Specification No. 22,222, A.D. 1903, or slip-ring free-pawl clutches, such as are shown in Fig. 2, are mounted on a sleeve fast with the pinions S, and can be held against turning by catches. When either clutch is released, the rollers act on inclines and thrust it against a disc D<1> or D<2> fast with the sun-pinion S. By holding the wheel T<2> and consequently the pinion S stationary, a high gear is obtained ; on slipping the clutch S', so as to lock the pinion S to the planet-carrier and driving the wheel T' to assist the engine, a middle gear results ; by slipping the clutch S', so as to lock the wheel T<2> to the pinion S, and driving partly through the wheel T<2> and partly through the wheel T', a slow speed is obtained ; an extra high gear is furnished by driving the wheel T<2> backwards, and a free engine is obtained by holding both the clutches S', S'. The wheel T' may be provided with a free-pawl clutch. A free-pawl clutch is shown in Fig. 2. The pawls U fit in circular recesses in the wheel V and are free to turn on studs W. When free, the pawls are forced into action by springs. The pawls are put out of action by a ring X, rotated in a groove in the wheel by means of a catch or lever Z<2>, and provided with recesses so that, in one position, it lifts the pawls, and in another position releases them. The pawls are brought into action by lowering the catch into engagement with the ring, and rotating the ring in the opposite direction. In a two-speed gear for a pedal-driven cycle, two sprocket-wheels are provided, the wheel on the high-gear side being provided with a slip-ring clutch, so as to allow the wheel on the low-gear side to be driven through an ordinary free-wheel clutch. By employing an epicyclic gear combined with a slip-ring clutch, together with the two pedal chains, a three-speed gear is obtained. In the gearing described in the prior Specification No. 22,222, A.D. 1903, the addition of a second chain on the pedal side with an ordinary pedal free-wheel on the hub gives an additional low pedal and engine gear when the planet slip-ring clutch is locked. The application of the slip-ring clutches to another type of variable-speed gear is shown in Fig. 3. In this arrangement, pairs of toothed wheels T', T<2>, T<3> on parallel shafts are in gear. On the driving-shaft, the low-gear wheel T' is provided with an ordinary free-wheel clutch, and the other wheels T<2>, T<3> are provided with slip-ring clutches S<2>, S<3> so that they can be made fast to the shaft when desired. Chain gearing may replace the toothed gearing. The clutchmounted wheels may be arranged on the sunpinion of an epicyclic gear, the outer ring of the gear being also in gear with a wheel fixed on the second motion shaft.