Albert W Vanderstappen

US Patent:

41517202, May 1, 1979

Filed:

Dec 8, 1977

Appl. No.:

5/858647

Inventors:

Albert W. Vanderstappen - Cary IL

International Classification:

F15B 1309

US Classification:

60479

Abstract:

A manually operable hydraulic actuator which utilizes a main pump and an auxiliary pump to quickly develop a relatively large useful hydraulic force, for example, in applying compression accessories to stranded conductors such as cables. The main pump develops a relatively high pressure from a low volume of hydraulic fluid to develop the primary hydraulic force. The auxiliary pump develops a relatively low pressure from a high volume of hydraulic fluid to produce rapid advancement of a force-applying piston relative to a work piece. Both the main and auxiliary pumps are operated by the opposed swinging movement of two manually operable handles. One of the handles is selectively movable between a first position for simultaneously actuating both the main and auxiliary pumps and a second position for actuating the main pump only. A pressure relief system is provided to ensure development of the maximum rated pressure of the force-applying piston before retraction thereof can be effected.