The structure of gas pressure regulator

A pressure regulator is comprised of three functional elements: a pressure reducing or restrictive element (generally a poppet valve), a sensing element (generally a diaphragm or piston) and a reference force element (generally a spring). In operation, the spring produces a force which opens the valve. Pressure introduced into the inlet port then flows through the valve and then presses against the sensing device (diaphragm or piston). The regulated pressure acts on the sensing element to produce a force which opposes the spring force and closes the valve.