Hydraulic flow control valve unit

Claim 1

A FLOW CONTROL VALVE UNIT, COMPRISING: A VALVE BODY HAVING INLET, OUTLET AND BYPASS PORTS; A FIRST PASSAGE CONNECTING THE INLET PORT AND THE OUTLET PORT; A FLOW CONTROL VALVE OPERABLE TO CONTROL THE FLOW OF FLUID THROUGH SAID PASSAGE TO EITHER THE OUTLET PORTION OR THE BYPASS PORT, SAID FLOW CONTROL VALVE INCLUDING A CYLINDRICAL VALVE BORE IN SAID VALVE BODY; A CYLINDRICAL VALVE IN SAID BORE HAVING A FIRST ANNULAR GROOVE ADAPTED WHEN THE VALVE IS IN AN OPEN POSITION TO FORM A PORTION OF SAID FIRST PASSAGE, AND A SECOND ANNULAR GROOVE ADAPTED WHEN THE CYLIDRICAL VALVE RESTRICTS SAID PASSAGE TO PASS FLUID FROM THE INLET PORT TO THE BYPASS PORT; MEANS PROVIDING A CONDUIT FROM SAID INLET PORT TO ONE END OF THE CYLINDRICAL VALVE BORE; A SPRING IN THE OTHER END OF THE CYLINDRICAL VALVE BORE URGING SAID CYLINDRICAL VALVE TOWARD THE ONE END OF THE BORE; MEANS PROVIDING A RESTRICTIVE ORIFICE IN SAID FIRST PASSAGE DISPOSED BETWEEN THE FLOW CONTROL VALVE AND THE OUTLET PORT; AND A SECOND PASSAGE IN SAID VALVE BODY LEADING FROM THE FIRST PASSAGE BETWEEN THE RESTRICTIVE ORIFICE AND THE OUTLET PORT AND CONNECTED TO THE OTHER END OF SAID BORE.