Shock absorber structure and the like

Claim 1

APPARATUS COMPRISING A CYLINDER HAVING OPPOSITE ENDS, ONE OF WHICH IS CLOSED, A PISTON SLIDABLY SUPPORTED IN SAID CYLINDER TO VARY THE PRESSURE OF A PRESSURE MEDIUM IN THE CYLINDER, A PISTON ROD CONNECTED TO THE PISTON AND EXTENDING AXIALLY IN THE CYLINDER, AND MEANS SUPPORTED AT THE OTHER OF THE ENDS OF THE CYLINDER AND ENGAGING THE PISTON ROD TO FORM A PRESSURE-TIGHT SEAL BETWEEN THE PISTON ROD AND THE CYLINDER WITH A FORCE DEPENDENT UPON THE PRESSURE OF THE MEDIUM IN SAID CYLINDER, SAID MEANS COMPRISING A RIGID CLOSURE MECHANISM SUPPORTED IN SAID CYLINDER, SAID CLOSURE MECHANISM HAVING A CENTRAL BORE, AN ANNULAR PACKING RING SUPPORTED IN THE BORE OF THE CLOSURE MECHANISM AND HAVING A CENTRAL OPENING FOR THE PASSAGE OF THE PISTON ROD, SAID PACKING RING HAVING AN UPPER AND A LOWER SURFACE, AN ANNULAR BODY ENCIRCLING THE PISTON ROD AND RESTING ON THE UPPER SURFACE OF THE PACKING RING WHILE BEING GUIDABLY SUPPORTED IN THE BORE OF THE CLOSURE MECHANISM, SAID ANNULAR BODY HAVING A FACE EXPOSED WITHIN THE CYLINDER FOR RECEIVING THE APPLICATION OF FORCE BY THE PRESSURE MEDIUM, SAID PACKING RING BEING RADIALLY AND AXIALLY RETAINED IN POSITION BY THE ANNULAR BODY AND THE CLOSURE MECHANISM, SAID OPENING IN SAID PACKING RING HAVING A CYLINDRICAL UPPER PORTION EXTENDING DOWNWARDLY FROM THE UPPER SURFACE OF THE RING AND A SMOOTH CONTINUOUS LOWER PORTION WHICH EXTENDS FROM THE CYLINDRICAL PORTION TO THE LOWER SURFACE AND WHICH WIDENS CONTINUALLY TO SAID LOWER SURFACE TO DEFINE A SUBSTANTIAL INTERIOR SPACE WITH THE PISTON ROD, SAID PACKING RING HAVING AN OUTER SMOOTH SURFACE WHICH INCLUDES A CYLINDRICAL PORTION ACCOMMODATED IN SAID BORE AND AN UPWARDLY EXTENDING PORTION ON SAID CYLINDRICAL PORTION WHICH NARROWS UPWARDLY TO SAID UPPER SURFACE WHICH IS IN CONTACT WITH THE ANNULAR BODY TO DEFINE A SUBSTANTIAL SPACE BETWEEN THE UPWARDLY EXTENDING PORTION OF THE RING AND THE ANNULAR BODY AND CLOSURE MEMBER.