Pressure control device, particularly in motor vehicle installations

Claim 1

IN A PRESSURE CONTROL DEVICE FOR A PNEUMATIC SYSTEM HAVING A PRESSURE RESERVOIR, IN COMBINATION, A HOUSING; A CYLINDRICAL CASING TIGHTLY AND REMOVABLY FITTED IN SAID HOUSING, SAID CASING HAVING A BOTTOM WALL AND AN OPEN END OPPOSITE SAID BOTTOM WALL; A COVER SECURED TO SAID CASING AND CLOSING SAID OPEN END THEREOF; A PAIR OF PASSAGE MEANS COAXIAL WITH SAID CASING AND RESPECTIVELY ARRANGED IN SAID COVER AND SAID BOTTOM WALL TO RESPECTIVELY PROVIDE THROUGH SAID COVER COMMUNICATION BETWEEN THE ATMOSPHERE AND THE INTERIOR OF SAID CASING AND TO PROVIDE THROUGH SAID BOTTOM WALL COMMUNICATION BETWEEN THE INTERIOR OF SAID CASING AND SAID PRESSURE RESERVOIR; VALVE MEANS MOVABLY ARRANGED IN SAID CASING FOR ALTERNATELY CLOSING SAID PAIR OF PASSAGE MEANS, SAID VALVE MEANS DEFINING TOGETHER WITH THE INNER SURFACES OF SAID CASING AND SAID COVER A PAIR OF END CHAMBERS AND AN ANNULAR CHAMBER INTERMEDIATE SAID END CHAMBERS AND SAID VALVE MEANS BEING FORMED WITH FURTHER PASSAGE MEANS PROVIDING COMMUNICATION BETWEEN SAID END CHAMBERS AND SAID ANNULAR CHAMBER; ADDITIONAL PASSAGE MEANS IN SAID HOUSING AND SAID CASING AND COMMUNICATING WITH SAID ANNULAR CHAMBER; SPRING MEANS OPERATIVELY CONNECTED TO SAID VALVE MEANS AND TENDING TO MOVE SAID VALVE MEANS TOWARD SAID BOTTOM WALL; AND FASTENING MEANS FOR FASTENING SAID CASING TO SAID HOUSING.