Brake cylinder release valve

Claim 1

IN A BRAKE CYLINDER RELEASE VALVE, THE COMBINATION OF A HOLLOW HOUSING HAVING END CLOSURES, A FIRST PISTON RECEIVING CHAMBER IN THE HOLLOW HOUSING, A CONNECTION FOR A BRAKE CONTROLLING DEVICE COMMUNICATING INTO SAID FIRST HOUSING CHAMBER, A SECOND CHAMBER IN THE HOLLOW HOUSING, A CONNECTION FOR A BRAKE CYLINDER COMMUNICATING INTO SAID SECOND HOUSING CHAMBER, MEANS IN SAID HOLLOW HOUSING DIVIDING THE FIRST AND SECOND HOUSING CHAMBERS FROM ONE ANOTHER AND HAVING A RESTRICTED OPENING THERETHROUGH, PISTON SEALING MEANS IN SAID FIRST HOUDING CHAMBER RECIPROCABLE IN SEALING FASHION WITHIN SAID CHAMBER, A VALVE BODY IN SAID SECOND HOUSING CHAMBER RECIPROCABLE WITHIN SAID CHAMBER, PISTON ROD MEANS CONNECTING SAID PISTON SEALING MEANS AND SAID VALVE BODY TO FORM A VALVE BODY-SEALING MEANS ASSEMBLY AND EXTENDING THROUGH SAID RESTRICTED OPENING AND OF INSUFFICIENT DIAMETER TO SEAL SAME, SAID VALVE BODY AND HOUSING PORTION FORMING SAID SECOND CHAMBER SO CONFIGURED AS TO CONTACT ONE ANOTHER IN SEALING FASHION WITHIN SAID SECOND CHAMBER ONLY WHEN THE ASSEMBLY IS IN A NORMAL OR OPEN POSITION, WHEREBY TO FORM A FLOW PASSAGEWAY THROUGH SAID HOLLOW HOUSING COMMUNICATING BETWEEN SAID CONNECTIONS AND BETWEEN OPPOSED PORTIONS OF SAID PISTON SEALING MEANS AND SAID VALVE BODY WHEN THE ASSEMBLY IS IN A NORMAL OR OPEN POSITION, MEANS ON SAID VALVE BODY FOR SEALING SAID RESTRICTED OPENING WHEN THE ASSEMBLY IS MOVED TO AN ABNORMAL OR CLOSED POSITION, SPRING MEANS IN THE HOLLOW HOUSING NORMALLY URGING THE ASSEMBLY AWAY FROM SAID CLOSED POSITION TO SAID OPEN POSITION, THE HOUSING PORTION FORMING THE FIRST CHAMBER ON THE SIDE OF THE PISTON SEALING MEANS AWAY FROM THE RESTRICTED OPENING BEING SEALED, PULL MEANS ENGAGEABLE WITH THE ASSEMBLY FOR OVERCOMING THE FORCE OF THE SPRING MEANS AND MOVING THE ASSEMBLY TOWARD CLOSED POSITION, THE HOUSING PORTION OF THE SECOND CHAMBER CONTINUOUSLY VENTED TO ATMOSPHERE ON THE SIDE OF THE VALVE BODY AWAY FROM THE RESTRICTED OPENING, SAID VALVE BODY AND PISTON ROD EACH AT LEAST PARTIALLY HOLLOW AND RECEIVING THEREWITHIN A SPOOL VALVE RECIPROCABLE IN WALL SEALING FASHION WITHIN AT LEAST A PORTION OF SAID HOLLOW VALVE BODY AND PISTON ROD, THE PORTION OF SAID SPOOL VALVE IN SAID VALVE BODY OF GREATER DIAMETER WHEREBY TO COMPRISE A PISTON PORTION THEREOF, A FIRST FLOW PASSAGE THROUGH SAID PISTON SEALING MEANS INTO THE PORTION OF SAID PISTON ROD CONTAINING SAID SPOOL VALVE, A SECOND FLOW PASSAGE THROUGH A PORTION OF SAID SPOOL VALVE INCLUDING A PORTION THEREOF RECEIVED IN SAID PISTON ROD AND A PORTION THEREOF RECEIVED IN SAID VALVE BODY, A THIRD PASSAGE COMMUNICATING FROM SAID SECOND PASSAGE OUTWARDLY OF SAID SPOOL VALVE PORTION IN SAID PISTON ROD, A FOURTH PASSAGE IN SAID PISTON ROD CONNECTABLE WITH SAID THIRD PASSAGE AT A CERTAIN POSITION OF SAID SPOOL VALVE, A FIFTH PASSAGE IN SAID SPOOL VALVE PISTON PORTION COMMUNICATING OUTWARDLY OF SAID PISTON PORTION, AND A SIXTH PASSAGE IN SAID VALVE BODY CONNECTIBLE WITH SAID FIFTH PASSAGE AT A CERTAIN POSITION OF SAID SPOOL VALVE WITH RESPECT TO SAID VALVE BODY.