Patent ID: 6945272

Claim:
A passively actuated valve comprising: a main valve body having a single chamber defined by chamber walls within the valve body, and further having first and second coaxial openings, and a third opening, the first, second and third openings in communication with the chamber, the first, second and third openings containing pressurized fluid at first, second and third pressure levels respectively; a piston slidingly and sealingly engaged within the chamber walls between the first and second coaxial openings, the piston being in a closed position, whereby the first, second and third pressurized fluids are isolated from each other when the first fluid pressure is greater than the second and third fluid pressures, and being in an open position when the second fluid pressure is greater than the first pressure, and the first fluid pressure is greater than the third fluid pressure, so that the first pressurized fluid is released through the third valve body opening.