Piston rod and piston assembly

Claim 1

IN COMBINATION, A PISTON AND PISTON ROD ASSEMBLY COMPRISING A PISTON ROD HAVING A THRUST SHOULDER (45) FORMED ADJACENT ONE END FACING TOWARD THE OTHER END OF THE ROD, SAID SHOULDER FLARING IN THE DIRECTION GOING FROM SAID ONE END TOWARD SAID OTHER END, A WEAR SLEEVE SNUGLY FITTED OVER SAID ROD EXTENDING FROM SAID SHOULDER TO ADJACENT SAID OTHER END OF THE ROD, SAID WEAR SLEEVE HAVING THE ONE END (97) ADJACENT SAID SHOULDER BEVELED CORRELATIVE TO SAID SHOULDER, A HYDRAULIC UNIT (47) HAVING AN AXIAL HOLE (73, 74) THERETHROUGH SNUGLY FITTED OVER SAID ROD ADJACENT THE OTHER END OF THE WEAR SLEEVE, SAID HYDRAULIC UNIT INCLUDING A HYDRAULIC PISTON (72) SAID AXIAL HOLE THROUGH SAID UNIT EXTENDING THROUGH THE AXIS OF SAID PISTON, SAID HYDRAULIC PISTON HAVING AN END FACE (95) ABUTTING THE SAID OTHER END OF THE WEAR SLEEVE, MEANS FOR SEALING BETWEEN SAID PISTON ROD AND SAID AXIAL HOLE (74) THROUGH THE PISTON PORTION OF THE HYDRAULIC UNIT INCLUDING AN O-RING (80) AROUND SAID ROD AND DISPOSED IN AN ANNULAR GROOVE (81) AROUND THE PERIPHERY OF SAID AXIAL HOLE, MEANS FOR LIMITING THE AXIAL TRAVEL OF SAID HYDRAULIC PISTON TOWARD SAID WEAR SLEEVE INCLUDING A FIRST INTERLOCKING PORTION ON SAID HYDRAULIC PISTON COMPRISING AN ANNULAR GROOVE (91) AROUND THE PERIPHERY OF SAID AXIAL HOLE AND A RESILIENT SPLIT RING (90) RECEIVED IN ANNULAR GROOVE (91) AROUND THE PERIPHERY OF SAID AXIAL HOLE, A SECOND INTERLOCKING PORTION ON SAID ROD COMPRISING A SQUARE STOP SHOULDER (92) FORMED ON SAID PISTON ROD ADJACENT SAID RING, FACING AWAY FROM SAID ONE END OF THE ROD, SAID ROD HAVING A TAPERED PORTION (93) ADJACENT SAID STOP SHOULDER, SAID SPLIT RING HAVING A SQUARE SIDE FACE (98) ADJACENT SAID STOP SHOULDER, SAID SPLIT RING HAVING A TAPERED INNER PERIPHERY (99) FLARING AWAY FROM SAID SIDE FACE, THE DISTANCE BETWEEN SAID STOP SHOULDER (92) AND SAID THRUST SHOULDER (45) BEING SLIGHTLY LESS THAN THE UNSTRESSED LENGTH OF SAID WEAR SLEEVE PLUS THAT PORTION OF THE HYLRAULIC PISTON FROM SAID END FACE THEREOF TO THE SIDE (96) OF THE SECOND SAID ANNULAR GROOVE WHICH SIDE IS FARTHEST FROM SAID END FACE OF THE PISTON LESS THE AXIAL EXTENT OF SAID SPLIT RING, SAID HYDRAULIC UNIT (47) FURTHER INCLUDING A HYDRAULIC CYLINDER (70), SAID CYLINDER HAVING A BORE 105 SNUGLY RECEIVING THE OUTSIDE OF SAID HYDRAULIC PISTON, SAID CYLINDER HAVING A CLOSED END (71) THROUGH WHICH EXTENDS SAID AXIAL HOLE THROUGH THE HYDRAULIC UNIT, MEANS TO SEAL BETWEEN SAID CLOSED END OF THE CYLINDER AND SAID ROD, THE LAST SAID SEALING MEANS INCLUDING AN O-RING (76) AROUND THE ROD AND RECEIVED IN AN ANNULAR GROOVE (77) AROUND THE PERIPHERY OF SAID AXIAL HOLE THROUGH THE CLOSED END OF THE CYLINDER, MEANS TO SEAL BETWEEN SAID BORE OF THE CYLINDER AND THE OUTSIDE OF SAID HYDRAULIC PISTON, THE LAST SAID SEALING MEANS INCLUDING AN O-RING (78) AROUND THE HYDRAULIC PISTON AND RECEIVED IN AN ANNULAR GROOVE (79) AROUND THE PERIPHERY OF SAID CYLINDER BORE, SAID PISTON ROD HAVING A PISTON MOUNTING PORTION (107) ADJACENT THE END OF SAID HYDRAULIC UNIT THAT IS REMOTE FROM SAID WEAR SLEEVE, SAID PISTON MOUNTING PORTION BEING TAPERED FLARING TOWARD SAID ONE END OF THE PISTON ROD, THE LAST SAID TAPERED PORTION HAVING A NON-SEIZING TAPER, A PISTON MOUNTED ON SAID PISTON MOUNTED PORTION OF SAID ROD, SAID PISTON HAVING AN AXIAL OPENING (108) CORRELATIVE TO SAID PISTON MOUNTING PORTION, MEANS FOR HOLDING SAID PISTON AGAINST AXIAL MOVEMENT TOWARD SAID OTHER END OF THE ROD, SAID HOLDING MEANS INCLUDING A THREADED PORTION (110) AT SAID OTHER END OF SAID ROD ADJACENT SAID PISTON MOUNTING PORTION, AND A NUT (48) SCREWED ONTO SAID THREADED PORTION AGAINST SAID PISTON, AND MEANS FOR PRESSURIZING SAID HYDRAULIC UNIT, SAID PRESSURIZING MEANS INCLUDING SAID PISTON ROD HAVING AN AXIAL PASSAGE (100) EXTENDING FROM SAID OTHER END OF SAID ROD TO A POSITION WITHIN SAID HYDRAULIC UNIT, SAID PISTON ROD HAVING A RADIAL PASSAGE (101) EXTENDING FROM SAID AXIAL PASSAGE TO THE ANNULAR SPACE (102) AROUND SAID ROD BETWEEN SAID HYDRAULIC CYLINDER AND HYDRAULIC PISTON OF SAID HYDRAULIC UNIT, A FITTING (62) ATTACHED TO THE END OF SAID AXIAL PASSAGE AT SAID OTHER END OF SAID ROD, SAID FITTING INCLUDING A CHECK VALVE PREVENTING FLOW FROM SAID AXIAL PASSAGE OUT OF SAID ROD, SAID FITTING FURTHER INCLUDING ATTACHMENT MEANS FOR CONNECTING A GREASE PUMP THERETO, AND HYDRAULIC FLUID UNDER PRESSURE FILLING SAID AXIAL AND RADIAL PASSAGES AND ANNULAR SPACE, SAID FLUID BEING GREASE.