Detector for a meter prover

摘要

A detector for a meter prover. The detector includes a non-ferromagnetic barrel having a cylindrical bore formed longitudinally therethrough. A magnetic proximity switch is mounted in the bore near one end of the barrel. A ferromagnetic piston is disposed in the bore near the other end of the barrel. A spring urges the piston away from the proximity switch. A pair of wipers surrounds the piston and forms a fluid tight seat between the bore and the piston. A passageway extends longitudinally through the length of the piston in order to permit fluid flow therethrough.