Patent attributes
An electro-pneumatic air pressure regulator includes a primary pressure introduction port, a secondary pressure output port, a pilot pressure chamber, a main valve for opening and closing a communicating conduit, a floating piston which actuates the main valve, a nozzle conduit via which the pilot pressure chamber is communicatively connected to the atmosphere, a flapper which includes a leaf spring facing an open end of the nozzle conduit, and an electromagnetic drive system which deforms the leaf spring to vary a position of the flapper relative to the open end of the nozzle conduit in accordance with the magnitude of an analogue input signal. The flapper includes a conical projection which projects toward the open end of the nozzle conduit. A conical recess corresponding to the conical projection is formed on an end face of the nozzle conduit around the open end thereof.