Lifting loads by crane - involves device which automatically engages crane hock with bolt attached to load

摘要

The load which is to be lifted by a crane is equipped with an attachment (3) consisting of two side plates (27) which support a bolt. The crane pulley block (1) has two pivoted hooks (13,15) which are lowered between the side plates (27). The lower edges of the hooks (13,15) are so shaped that the hooks (13,15) are pressed on to the bolt (35) they are swung apart from each other and slide over opposite sides of the bolt (35). As the pulley block (1) is raised an arm (57) attached to the pulley block, swings the hooks (13,15) together so that they engage the bolt (35) and so enable the load to be lifted.