Fluid motor and control valve assembly therefor

Claim 1

IN A FLUID MOTOR AND CONTROL VALVE ASSEMBLY, A HOUSING HAVING A MOTOR CYLINDER THEREIN, A PISTON SLIDABLY RECEIVED IN SAID CYLINDER, PASSAGES IN SAID HOUSING FOR COMMUNICATING THE ENDS OF SAID CYLINDER WITH A FLUID PRESSURE SOURCE, MEANS FOR TRAPPING FLUID IN ONE END OF SAID CYLINDER, WHEREBY THE FLUID PRESSURE IN SAID ONE END OF SAID CYLINDER IS MAINTAINED EVEN THOUGH THE PRESSURE OF THE FLUID PRESSURE SOURCE MAY BE SUBSEQUENTLY REDUCED, AND MEANS FOR PERMITTING THE FLUID TRAPPED IN SAID ONE END OF SAID CYLINDER TO ESCAPE IN RESPONSE TO HIGH FLUID PRESSURE BEING DIRECTED INTO THE OTHER END OF SAID CYLINDER, SAID MEANS FOR TRAPPING THE FLUID AS AFORESAID COMPRISING A ONE-WAY CHECK VALVE, AND SAID MEANS FOR PERMITTING THE TRAPPED FLUID TO ESCAPE IN RESPONSE TO HIGH FLUID PRESSURE BEING DIRECTED TO THE OTHER END OF SAID CYLINDER COMPRISING A SPOOL VALVE MEANS DISPOSED IN A BORE IN FLUID COMMUNICATION WITH BOTH ENDS OF SAID CYLINER, SAID SPOOL VALVE MEANS HAVING AN ENLARGED PORTION WHICH IS ACTED ON BY THE FLUID PRESSURE IN SAID OTHER END OF SAID CYLINDER AND A SMALLER PORTION ACTED ON BY THE FLUID PRESSURE IN SAID ONE END OF SAID CYLINDER, SAID SPOOL VALVE MEANS ALSO HAVING A PAIR OF AXIALLY SPACED TRANSVERSE PASSAGES INTERCONNECTED BY AN AXIAL PASSAGE, SAID SPOOL VALVE MEANS WHEN ACTED UPON BY HIGH FLUID PRESSURE IN SAID ONE END OF SAID CYLINDER BEING ADAPTED TO BE MOVED TO A FIRST POSITION WHEREAT FLUID COMMUNICATION BETWEEN SAID ONE END OF SAID CYLINDER AND A PASSAGEWAY COMMUNICATING SAID BORE WITH THE EXTERIOR OF SAID HOUSING IS BLOCKED, AND WHEN ACTED UPON BY HIGH FLUID PRESSURE IN THE OTHER END OF SAID CYLINDER, SAID SPOOL VALVE MEANS IS ADAPTED TO BE MOVED TO A SECOND POSITION WHEREAT FLUID COMMUNICATION BETWEEN SAID ONE END OF SAID CYLINDER AND SAID PASSAGEWAY IS ESTABLISHED VIA A BRANCH PASSAGE IN SAID HOUSING WHICH COMMUNICATES SAID ONE END OF SAID CYLINDER WITH ONE OF SAID TRANSVERSE PASSAGES IN SAID SPOOL VALVE MEANS.