Silent self-controlled orificial restrictor

摘要

An orificial restrictor for use in a ballasting system for an underwater vehicle utilizing a plurality of multi-holed orifice plates set in series within a casing. A hollow cylinder is slidably positioned within the casing and carries fluid supplied through an inlet in the case. A spring biases the cylinder toward the inlet and fluid pressures opposes the spring force to move the cylinder away from the inlet whereby the hollow cylinder automatically positions itself with pressure changes to control the number of orifice plates subject to flow.