Abstract: In a liquid loading system for the gravity loading of a liquid storage tank from a tank truck the present invention provides an improved mechanism for interrupting the flow of liquid when the level of liquid in a tank rises above a predetermined level. The structure includes a valve in the fill line which is moveable between an open position and closed position. A pressure responsive latch means is provided for releasably locking the valve in the open position. A vent passage communicates between the pressure responsive latch means and a predetermined level below the upper end of the underground storage tank. A vacuum passage communicates between the vent passage and a vacuum source in the fill line. The flow of liquid through the liquid fill line generates the vacuum in the fill line in the area of the vacuum passage. Until the level of liquid in the underground tank rises above the end of the vent passage, atmosphere from within the tank is drawn into the vacuum passage from the vent passage.

Abstract: In a dispenser nozzle having, a main body portion, a filling tube projecting from one end of said main body portion, and a liquid flow passage extending through said main body and said filling tube, the filling tube being adapted to be located within the open end of a neck of a fuel storage tank of a vehicle or the like, a control valve mechanism for controlling the flow of liquid through said liquid flow passage, said mechanism including a valve operating mechanism and latching means for releasably engaging said valve operating mechanism to render said valve operating mechanism operative when engaged by said latching mechanism and inoperative when released by said latching mechanism, the improvement of sensor means mounted on said nozzle and disposed adjacent said filling tube, said sensor means communicating with said latch means to release said latch means with respect to said valve operating mechanism to render said valve operating mechanism inoperative when said filling tube is now disposed in a predeter

Abstract: A nozzle for use in controlling the flow of liquids incorporating a positive pressure generating device which provides a positive pressure to a diaphragm chamber which serves to retain the valve in an open position after manual opening of the valve by means of a manually operable actuator mechanism. The valve actuator mechanism includes closure means for moving the valve closure means to a closed position and releasable opening means for moving the valve closure means to an open position. A releasable opening means is released when the diaphragm chamber is positively pressurized at a pressure sufficient to retain the valve closure means in a predetermined open position. This provides a nozzle which, after initial manual opening, will be automatically closed when the positive pressure provided by the positive pressure generating device is cut off by the rising level of liquid within the tank.