Telescopic grab for transporting heavy loads, has grab arms held in position by steplessly lockable safety devices

摘要

A steplessly lockable safety device extends between each grab arm and the grab casing (2) in order to fix the grab arm into position. The safety device comprises a hydraulic piston cylinder (10) and a check valve (11), a non-driven hydraulic cylinder with two chambers connected via a check valve, a preferably tempered threaded bar and a follower or a preferably profiled bar with a four-sided cross-section and a clamping device.