Hoisting device for high-power crane

摘要

This hoisting device is intended for orienting and balancing in space the load suspended from the jib of a high-power crane and comprises for each oblique suspension rope attached to the load a traction assembly comprising in turn two pairs of cylinders each associated with one traction block and operating by turns and step-by-step in order to provide a substantially constant traction rate independent of that of the other groups. Conduit means connect said cylinders to the control means housed in the crane control cab and are provided with interconnecting means for balancing the forces in each rope as desired by the operator.