1. US20130068984 - AIR SHUTOFF SWING GATE VALVE

A swing gate valve is provided having a swing gate, a pivotable shaft having a swing arm disposed thereon such that rotation of the shaft causes rotation of the swing arm, a spring to urge the swing gate toward its closed position, a trigger assembly for securing the swing gate in its open position and for triggering the shaft to rotate including an actuator having a shaft and a receiver in the swing gate to receive the shaft, wherein when the shaft is in an extended position, the shaft is disposed in the receiver and the swing gate is locked in its open position, and wherein actuation of the actuator causes the shaft to withdraw to a retracted position out of the receiver, wherein the spring causes the pivotable shaft to rotate to move the swing gate to its closed position.