| 摘要 |
976,591. Change-speed gear. FICHTEL & SACHS A.G. March 1, 1962 [March 11, 1961], No. 8012/62. Heading F2D. [Also in Division B7] In a combined twospeed gear and brake hub for a bicycle of the kind wherein a simple sunring train with permanently fixed sun 24 provides over - and direct - drive by selectively clutching an input sprocket hub 4 to the planet carrier 19 or ring gear 21, which latter drives a wheel hub 7 through a ratchet clutch 31 and the formar is helically splined to a brake cone 25 which moves axially to engage a brake 26 on back-pedalling, a second ratchet clutch 30 is provided between the brake cone 25 and wheel hub 7 and a lost motion coupling 29 is provided between the ring gear 21 and first ratchet clutch 31 so that if the bicycle is wheeled backwards after braking the pawls of the second ratchet 30 are picked up by the ratchet teeth 33 and disengage the brake prior to reverse rotation of the gear. The angular lost motion of the coupling 29 is greater than the angle between the teeth of the ratchet 30. |
