Gordon D Fox

US Patent:

39496503, Apr 13, 1976

Filed:

Jan 16, 1975

Appl. No.:

5/541601

Inventors:

Leland F. Blatt - Grosse Pointe Shores MI
Gordon J. Fox - Clinton Township MI

International Classification:

F01B 3104

US Classification:

92108

Abstract:

An equal area displacement hydraulic cylinder includes a hollow reciprocal piston rod and piston, and between said cylinder and rod, a first chamber communicating with a first port for retracting the piston rod. A rod end closes said piston rod and includes an attachment device. A hollow tube extends within the piston rod and is anchored at one end to the cylinder and terminates in a second port. A stationary piston is mounted on the other end of said tube. Said tube defines a second chamber communicating with the rod end and second piston for advancing the piston rod when said second port is pressurized. The working area of the reciprocal piston is the same as the working area of the rod end, whereby equal rod force is applied to the reciprocal piston rod in either direction.