GB933169A - Variable speed ratchet gearing - Google Patents

Abstract

933,169. Variable-speed ratchet gearing; linkwork. J. F. G. M. L. CHARPENTIER. Oct. 20, 1961, No. 37666/61. Classes 80 (2) and 80 (3). In a variable-speed ratchet gearing the effective radius of the driving crank is increased by centrifugal force generated by speed increase of the driving shaft. A driving shaft 150 is rigid with a disc 162 to which is pivoted, at 164, a crank-arm 166, the crank-pin 172 of which moves outwards in a track 168 against a spring 170 as the speed of the shaft 150 increases. The crank-pin 172 is connected by a link 178 to a rocker arm 174 in one-way driving con nection through a friction ratchet clutch 182 with a planetary shaft 180 carried in bearings 184 in a rotary cas ing 186 journalled on bear ings 154, on the shaft 150 and rigid with the output shaft 158. A planetary gear 192, on shaft 180, engages a sun gear 194 held against reverse rotation by a ratchet clutch 202 on a trunnion 198 forming part of a stationary casing 156. The clutch 202 has a manual disengaging lever 210 to allow overrun braking from the output shaft 158, connected to the wheels of a vehicle, to the input shaft 150 driven from the engine. An overrunning one-way clutch 206 is provided between the fixed casing 156 and a trunnion 190 on the rotatable casing to act as a hill-holder, a further one-way clutch disengageable by a lever 212 provides for free-wheeling between the engine and the rotatable casing. In operation, the throw of crank-arm 166 is determined by speed and torque to vary the transmission ratio, at full throw the crank-arm locks against the casing to provide a direct drive. A plurality of planetary shafts may be employed to provide continuous drive.