Improvements relating to irreversible rotary transmission devices

摘要

315,335. Bricard, R., and Bricard Ancienne Maison Sterlin. April 10, 1928. Levers and rods, locking.-An irreversible rotary transmission device between coaxial shafts, in which any independent or uncontrolled movement of the driven shaft automatically brings frictional gripping means into action to stop such movement, comprises a crank pin 25 on the driving-shaft adapted to bear against one or other of a pair of loose radial levers 26, 27, the inner ends of which engage jaws 36, 37 on the driven shaft .whilst their outer ends are located between the ends of annular friction segments 32, 33 arranged within a fixed casing 23. Between the loose levers and segments are arranged loose pins 29, 30, 31, and 34 functioning as pivots. The pivots 30, 29, 31 are so. arranged that pressure of either of the jaws 36, 37 on the lever pair produces a toggle expanding effect on the friction segments, causing them to grip the casing, whilst the opposite, releasing, effect is produced by. pressure of the driving-pin 25 in either direction. The segments 32, 33 are loosely located by pins (not shown) on the crank disc. Means may be provided to enable the gripping-means to be wholly or partially put out of action at will. The driving and driven members may be directly coupled by a pin, key, pawl, or the like, rendering the levers 26, 27 inoperative, or a graduated action, regulating their play, may be obtained by use of an elliptical or camshaped coupling-pin 58, Fig. 5, on one member 21 located between jaws 60 on the other member 39, the gripping action of the parts shown in Fig. 1 being gradually reduced as the cam is rotated to reduce play in the fork 60. The same effect may be obtained by use of an adjustable elliptical driving-pin 25.