Control piston for liquid propellant gun injector

Claim 1

The improvement in a regenerative feed liquid propellant gun having a propellant injection piston and a charge chamber, said improvements for controlling the movement of the said injection piston, comprising: a. a control piston having a first face with a first effective pressure area and a second face with a second effective pressure area; b. means for rigidly attaching said control piston to said propellant injection piston; c. means for applying hydraulic fluid under pressure to the first face of the said control piston; d. means providing a fixed orifice through said control piston from said first face to said second face for providing a determined flow of hydraulic fluid therethrough; e. a cylindrical sleeve cooperating with said control piston, said cylindrical sleeve having spaced apart ports opening to the first and second faces of said control piston; and f. means cooperating with said ports to provide a by-pass passage for the flow of hydraulic fluid; and g. means moving said control piston relative to said ports for restricting the flow of hydraulic fluid through said by-pass passage to vary the resistance to the movement of said control piston.