Multistage telescopic hydraulic ram - has control members in crowns of individual hollow pistons

摘要

The multi-stage telescopic hydraulic ram has two or more hollow pistons sliding one inside the other. A control device causes the individual pistons to extend fully in succession, starting with the largest one. The device has control members accommodated in the crowns (10) of the hollow pistons (2,3). These can include mechanical opening components actuated when the piston reaches the end position and typically formed by mechanically-released non-return valves. The component axes deviate from that of the ram (1), with two-part pref. straight actuating tappets.