Fluid pressure motor

Claim 1

A FLUID PRESSURE MOTOR COMPRISING AN ELONGATED CYLINDER HAVING A BORE CLOSED AT ONE END AND OPEN AT THE OPPOSITE END: A PISTON AND ROD ASSEMBLY MOVABLY POSITIONED IN SAID BORE AND DEFINING THEREWITH HEAD AND ROD CHAMBERS; A FIRST CONDUIT IN FLUID COMMUNICATION WITH AT LEAST ONE OF SAID HEAD AND ROD CHAMBERS, SAID ASSEMBLY INCLUDING A PISTON ROD MOVABLE IN THE BORE THROUGH SAID OPEN END, SAID PISTON ROD INCLUDING SECOND AND THIRD CONDUITS; A FIRST PISTON PART SECURED AGAINST AXIAL MOVEMENT RELATIVE TO THE ROD; A SECOND PISTON PART AXIALLY SPACED FROM THE FIRST PISTON PART AND ALSO SECURED AGAINST AXIAL MOVEMENT RELATIVE TO THE ROD; A CAM FOLLOWER BETWEEN THE PISTON PARTS FIXED AGAINST LONGITUDINAL MOVEMENT RELATIVE TO THE ROD AND RADIALLY MOVABLE INTO AND OUT OF FRICTIONAL ENGAGEMENT WITH SAID BORE; A CAM HAVING AN OPERATING POSITION IN WHICH IT OPERATIVELY ENGAGES THE CAM FOLLOWER AND ANOTHER OPERATING POSITION IN WHICH IT OPERATIVELY DISENGAGES THE CAM FOLLOWER, IN ONE POSITION THE FOLLOWER BEING IN LOCKING FRICTIONAL ENGAGEMENT WITH THE BORE AND IN OTHER POSITION THE FOLLOWER BEING MOVABLE IN THE BORE; SAID CAM HAVING FIRST AND SECOND PORTIONS COOPERATING WITH SAID FIRST AND SECOND PISTON PARTS TO DEFINE FIRST AND SECOND CHAMBERS, SAID FIRST AND SECOND CHAMBERS IN FLUID COMMUNICATION WITH SAID SECOND AND THIRD CONDUITS, RESPECTIVELY; RESILIENT MEANS BIASING SAID CAM INTO ONE OPERATING POSITION; AND FLUID PRESSURE MEANS TO MOVE SAID CAM INTO ITS OTHER OPERATING POSITION AGAINST THE BIAS OF THE RESILIENT MEANS, SAID FLUID PRESSURE MEANS IN FLUID COMMUNICATION WITH SAID SECOND AND THIRD CONDUITS.