Relief-check assembly for directional control valve

Claim 1

IN COMBINATION, A DIRECTIONAL CONTROL VALVE COMPRISING A HOUSING HAVING AN INLET PORT FOR FLUID UNDER PRESSURE, A RETURN PORT, AND A PAIR OF SERVICE PORTS, AND A VALVE MEMBER MOVABLE IN SAID HOUSING FROM NEUTRAL POSITION BLOCKING FLUID COMMUNICATION BETWEEN SAID INLET PORT AND BOTH SERVICE PORTS TO EITHER OF TWO OPERATING POSITIONS SELECTIVELY COMMUNICATING SAID SERVICE PORTS WITH SAID INLET AND RETURN PORTS; AND A PAIR OF COMBINATION RELIEF-CHECK VALVE ASSEMBLIES NORMALLY CLOSING COMMUNICATION BETWEEN THE RESPECTIVE SERVICE PORTS AND SAID RETURN PORT AND INCLUDING SPRING-BIASED VALVE MEMBERS ARRANGED TO BE MOVED AS CHECK VALVE MEMBERS BY FLUID UNDER PRESSURE IN SAID RETURN PORT OF MAGNITUDE EXCEEDING THAT IN THE RESPECTIVE SERVICE PORTS TO POSITIONS ESTABLISHING FLUID COMMUNICATION BETWEEN SAID RETURN PORT AND THE RESPECTIVE SERVICE PORTS, AND TO BE MOVED AS RELIEF VALVE MEMBERS BY FLUID UNDER PRESSURE IN THE RESPECTIVE SERVICE PORTS OF MAGNITUDE EXCEEDING THAT IN SAID RETURN PORT TO A POSITION SIMILARLY ESTABLISHING FLUID COMMUNICATION BETWEEN THE RESPECTIVE SERVICE PORTS AND SAID RETURN PORT; SAID VALVE ASSEMBLIES BEING OPPOSITELY DISPOSED SO THAT FLUID UNDER PRESSURE RELIEVED BY ONE SPRING-BIASED VALVE MEMBER FROM ONE SERVICE PORT TO SAID RETURN PORT IMPINGES ON THE OTHER SPRING-BIASED VALVE MEMBER TENDING TO MOVE THE LATTER TO ESTABLISH FLUID COMMUNICATION BETWEEN SAID RETURN PORT AND THE OTHER SERVICE PORT..