Hook with pivoted safety catch - has plunger which has to be depressed to free catch

摘要

A hook has a pivoted safety catch which is engaged automatically to close the hook on engagement of a load on the hook. The safety catch has a rib with an opening in it which engages a necked portion of a spring loaded plunger located in a recessed hole in the body of the hook. The spring biasses the plunger outwardly so as to close the safety catch over the opening of the hook. The neck and opening have conical portions which engage to provide a frictional force which prevents release of the catch. The plunger has to be depressed to free the catch.