Shock-absorbing fluid-actuated fastener installation tool

摘要

A push-pull tool for setting multi-piece fasteners includes a piston that is movable back and forth within a cylinder in response to fluid forces on opposite faces of the piston. One of the fluids is an air-oil foam mixture that acts essentially as an incompressible liquid force-transmitter, while being somewhat compressible so as to absorb shock loadings associated with rapid piston movements. A check valve is included in the system to admit atmospheric air into the air-oil foam mixture, to thereby partially compensate for oil leakage that might inadvertantly take place across the piston seals.