Adjustable fluid flow restrictor

Abstract

There is disclosed an adjustable fluid flow restrictor for controlling the rate of fluid flow into a conduit, the restrictor having a body which seals the central opening of a fluid chamber and through which body there is a central opening having a cylinder section and a truncated cone section the cylinder section having a set-screw engaged therein, the threads thereof forming spiral grooves through which fluid maybe conducted at a rate controlled by positioning the end of the set-screw adjacent the walls of the truncated cone section to obstruct and adjustably close the openings into the spiral grooves thereby restricting the rate of fluid flow. An alternate form of the restrictor employs a ball-valve between the set-screw and the truncated cone section, the space between the ball-valve and the walls of the truncated cone section being adjusted by the set-screw to restrict the flow of fluid. Longitudinal ridges maybe added to the walls of the truncated cone section to prevent complete obstruction of the truncated cone section by the ball-valve for more accurate control of slow fluid rates. The restrictor body itself may be used as a by-pass valve by being moveably located in the fluid chamber and biased against a valve seat formed around the central opening of the fluid chamber. A plunger is moveably mounted through the walls of the fluid chamber to contact and push the restrictor body away from the valve seat and allow fluid to pass around the restrictor and by-pass the internal flow of fluid through the restrictor.