GB568560A - Improvements relating to hand cranks for elevating and training mechanisms - Google Patents

Abstract

568,560. Clutches. MECHANIZATIONS & AERO, Ltd., and LANDSTAD, H. F. Feb. 25, 1939, No. 6308. [Class 80 (ii)] [Also in Groups XXI and XXXI] Hand-cranks for elevating and training mechanisms comprise in combination a crankboss freely mounted on a bearing coaxially with the spindle to be actuated, a member on the spindle through which motion can be imparted to the spindle from the boss, and a catch movable relatively to such member and boss by the user for effecting or interrupting a driving connection between the member and boss. The spindle a to be actuated is mounted by ball bearings c in a cylinder b, which freely supports by ball bearings e a crank-boss d. On an arm f projecting from the crank-boss d is pivoted at g a hand-operated catch h, which is adapted to engage one of a series of peripheral. notches on a disc i, fixed to the spindle a, so as to provide a driving connection between the boss and spindle. The catch is held in its engaged or disengaged position by a bell-crank finger lever k pivoted on a pin p, the lower arm of the bell-crank lever k being adapted to engage one of a pair of notches m in the arm f, under the resilient constraint of a spring-loaded plunger n bearing on a flat o on the pivot pin p. In its disengaged position, the catch h engages one end of a slot q in the arm f through which the catch extends. The crank r, which may have two handles y, z, is removably inserted in a socket s in the arm f, and is secured therein by a cam or rotatable key t, adapted to engage a recess u in the crank and controlled by a finger lever v, which is held by a spring strip w.