Safety trip for hoist - has movable drum and stop to contact operating lever on overload

摘要

The hoist drive consists of a cable winding drum (1) connected to a motor (2). The cable (5) passes over a jockey pulley (13) which is fixed to the axle (14). The drum is mounted onto a hinged plate (6) fixed at one end (7). The plate rests on the helical spring (8) at the opposite end to the hinge. The control lever (4) is mounted on the drum. The lever has an extension (12). The hoist frame has a post (9) which carries an adjustable stop (10). Overloading of the hoist will pull the drum over against the spring and against the stop (10) to trip the operating lever.