Impact force shaping head

摘要

An impact force shaping head includes an elongated casing having an interior wall, an open end and a closed end and contains a liquid. A piston is slidingly mounted within the casing and extends longitudinally beyond the open end of the casing. The piston sealingly engages the interior wall of the casing to define a liquid-filled first chamber between the piston and the closed end of the casing. A reservoir contains liquid and a conduit connects the first chamber with the reservoir. A control valve controls the flow of liquid through the conduit. The control valve is operative in response to changes in the pressure of the liquid contained in the first chamber.