Pressure regulator and pneumatic noise filter

Claim 1

IN A PRESSURE REGULATOR HAVING A HOUSING ENCLOSING A VALVE CHAMBER WITH A PASSAGE THERETHROUGH SURROUNDED BY SEAT AREA, A VALVE ELEMENT MOVABLE TOWARD AND FROM THE SEAT AREA TO CONTROL FLOW OF FLUID THROUGH SAID PASSAGE, INLET AND OUTLET PASSAGES COMMUNICATING WITH THE CHAMBER ON DIFFERENT SIDES OF THE SEAT AREA, A REGULATING PRESSURE CHAMBER HAVING A MOVABLE WALL AND FOR SENSING THE DOWNSTREAM PRESSURE, MOTION-TRANSMITTING CONNECTIONS BETWEEN THE MOVABLE WALL AND THE VALVE ELEMENT, AND A COMMUNICATING PASSAGE THROUGH WHICH FLUID ON THE DOWNSTREAM SIDEOF THE VALVE ELEMENT FLOWS TO AND FROM THE REGULATING PRESSURE CHAMBER, THE IMPROVEMENT WHICH COMPRISES A FLOW OBSTRUCTION IN THE COMMUNICATION PASSAGE INCLUDING AN ELEMENT MOVABLE INTO DIFFERENT POSITIONS TO REDUCE THE AMOUNT OF FLOW OBSTRUCTION IN THE COMMUNICATION PASSAGE AND TO THEREBY SHORTEN THE TIME FOR SUDDEN CHANGES IN DOWNSTREAM PRESSURE TO BE SENSED AT SAID MOVABLE WALL OF THE REGULATING PRESSURE CHAMBER, THE OBSTRUCTION HAVING A BIAS TOWARD A MID POSITION AND BEING MOVABLE IN OPPOSITE DIRECTIONS FROM SAID MID POSITION BY PRES-