Patent ID: 7527069

Claim:
A pressure relief check valve system, comprising: a valve body having an upstream side, a downstream side, and a flow channel that extends between the upstream and downstream sides; a flapper rotationally mounted on the valve body and movable between a closed position, in which the flapper at least substantially seals the flow channel, and an open position, in which the flapper unseals the flow channel; a magnet disposed within and movable with the flapper; an electromagnet disposed within the valve body and configured to selectively receive electrical current, the electromagnet operable, upon receipt of the electrical current, to either magnetically attract or not magnetically attract the magnet, to thereby at least substantially inhibit flapper rotation from the closed position or allow flapper rotation to the open position, respectively; and a pressure sensor circuit configured to sense at least a fluid pressure on the upstream side of the valve body and operable, based on the sensed fluid pressure, to selectively supply or interrupt the electrical current to the electromagnet.