Patent attributes
A valve includes a body; a liquid flow passage defined in the body and including a liquid inlet and a liquid outlet; a vent passage defined in the body and including an air inlet and an air outlet; a valve seat defined in the liquid flow passage; a liquid seal located adjacent the valve seat; a stem connected to the liquid seal and extending in the liquid flow passage away from the liquid seal through an aperture defined in the body. The stem includes a distal end located external to the body. The stem is movable to and from a first position where the liquid seal is mated with the valve seat and a second position where the liquid seal is unseated from the valve seat. An actuator is connected to the distal end of the stem. The actuator is selectively movable to move the stem from the first position to the second position. A check-valve is adapted to block flow of liquid from the air outlet to the air inlet in the vent passage, and to allow flow of air from the air inlet to the air outlet in said vent passage. The valve optionally further includes a surge control device and/or a keeper for the check-valve seal.
