Safety pulley for workman - has centrifugal locking pawls engaging ratchet wheel movable axially by screw

摘要

The pulley of the main patent has a centrifugal locking device which has pawls moving to engage with a ratchet wheel mounted to slide on a screw on the axis of the pulley. The centrifugal effect is obtained by counterweights opposite the pawls relative to the pulley shaft. Sliding of the ratchet wheel on the screws is by use of a running hexagon. Compression springs assure reliable operation.