Fluid motor

Claim 1

IN A RECIPROCAL TYPE FLUID POWERED MOTOR UNIT COMPRISING AN OUTER MEMBER, A FRONT END PLUG CLOSING THE CORRESPONDING END OF SAID MEMBER, SAID PLUG INCLUDING AN EXTERIORLY ACCESSIBLE PRESSURIZED FLUID DISTRIBUTING PORT, VALVE MEANS MOUNTED IN SAID PLUG, SAID VALVE MEANS COMPRISING PLURAL CHECK VALVE MECHANISMS, A PISTON HEAD DISPOSED IN SAID OUTER MEMBER REARWARDLY OF SAID PLUG, A HOLLOW PISTON ROD ATTACHED TO SAID HEAD, SAID PISTON ROD BEING SPACED RADIALLY INWARDLY FROM SAID OUTER MEMBER TO DEFINE A PRESSURIZED FLUID RECEIVING CHAMBER THEREBETWEEN, AND AXIALLY APERTURED STEM ATTACHED TO SAID PLUG AND EXTENDING REARWARDLY THEREOF INTERIORLY OF SAID ROD AND THROUGH SAID HEAD, SAID HEAD AND ROD BEING ADAPTED FOR RELATIVE AXIAL MOVEMENT WITH RESPECT TO SAID OUTER MEMBER AND SAID STEM, A BASE MEMBER SECURED TO SAID STEM IN REARWARD AXIALLY SPACED RELATION WITH RESPECT TO SAID HEAD, SEALING MEANS COACTING BETWEEN SAID BASE MEMBER AND THE INTERIOR OF SAID ROD AND BETWEEN SAID HEAD AND SAID STEM TO PROVIDE A LEAKAGE PROOF PRESSURIZED FLUID CHAMBER BETWEEN SAID STEM AND SAID ROD AND INTERMEDIATE SAID HEAD AND SAID BASE MEMBER, PASSAGEWAY MEANS PROVIDING FOR FLUID COMMUNICATION BETWEEN SAID CHAMBER AND THE INTERIOR OF SAID STEM, SECOND PASSAGEWAY MEANS IN SAID PLUG COMMUNICATING WITH SAID AXIAL APERTURE IN SAID STEM, ONE OF SAID CHECK VALVE MECHANISMS NORMALLY CLOSING SAID SECOND PASSAGEWAY MEANS FROM COMMUNICATION WITH SAID PORT IN SAID PLUG, A THIRD PASSAGEWAY MEANS IN SAID PLUG COMMUNICATING WITH THE FORWARD END OF SAID HEAD, AND ANOTHER OF SAID CHECK VALVE MECHANISMS NORMALLY CLOSING SAID THIRD PASSAGEWAY MEANS FROM COMMUNICATION WITH SAID PORT IN SAID PLUG, SAID CHECK VALVE MECHANISMS BEING DEACTIVATED UPON APPLICATION OF PRESSURIZED FLUID TO SAID PORT WHEREBY PRESSURIZED FLUID IS SIMULTANEOUSLY APPLIED TO BOTH THE FORWARD AND REARWARD ENDS OF SAID HEAD VIA SAID PASSAGEWAY MEANS FOR REDUCING THE ACTUATING FORCE OF SAID MOTOR UNIT DURING EXTENSION OF THE LATTER, AND MEANS PROVIDING FOR AXIAL FLOW OF PRESSURIZED FLUID BETWEEN SAID OUTER MEMBER AND SAID HEAD AND INTO AND OUT OF THE FIRST MENTIONED CHAMBER DURING ACTUATION OF SAID MOTOR UNIT.