Patent ID: 8783644
Filing Date: 2014-07-22
Classification: A62C,F16K

Abstract:
1. A controlled pressure release valve for preventing overpressure in a protected area upon delivery of gas, the valve comprising: a valve body having a gas inlet for connection to a gas container under pressure, a tapered valve seat, and a gas outlet for delivering gas to the protected area; a slidable spool housed in the valve body, the slidable spool formed of a cylindrical head portion on one side of a tapered midsection, the tapered midsection adjacent to a cylindrical tail portion of larger diameter than the cylindrical head portion, the cylindrical tail portion at an opposite side of the tapered midsection as the cylindrical head portion, and having a first end at the cylindrical head portion and a second end at the cylindrical tail portion, and the slidable spool being movable between a first position, wherein the tapered midsection is seated in the tapered valve seat, and a second position; a primary flow passage connecting the gas inlet and the gas outlet that is formed when the slidable spool moves away from the first position and the cylindrical head portion moves inside the tapered valve seat, wherein a cross-sectional area of the primary flow passage increases with lineal movement of the slidable spool as the cylindrical head portion lineally moves inside the tapered valve seat; a first chamber located adjacent the first end of the slidable spool, the first chamber having a first gas pressure, the cylindrical head portion being positioned between the first chamber and the tapered midsection, the cylindrical head portion defining a wall of the first chamber; a second chamber located adjacent the second end of the slidable spool, the second chamber applying a second gas pressure to the slidable spool such that the second gas pressure biases the slidable spool toward the first position; a spring for biasing the slidable spool in the first position; a bleed passage connected to the second chamber; and a valve actuator for actuating the valve by opening the bleed passage, wherein when the valve is actuated, the first and second chambers are in communication with the gas inlet and the slidable spool is urged to the second position at a rate that is a function of a decreasing pneumatic gas pressure in at least one of the chambers.