Patent ID: 7322273
Filing Date: 2008-01-29
Classification: F15B

Abstract:
1. A hydraulic piston and cylinder unit comprising: a cylinder assembly defining a cylindrical chamber; a piston member mounted in said cylindrical chamber for reciprocating movement therein in response to movement of hydraulic fluid under pressure into and out of said chamber; a piston rod member connected to said piston member for movement therewith and extending from one end of said cylinder assembly; said piston rod and piston members having meshing threads thereon configured to be meshingly interengaged when said members are rotationally moved in one direction into an assembled position relative to one another; and a peripheral retainer disposed between and engaging the piston rod member and the piston member to resist relative rotation between the members, the peripheral retainer including deformable material configured and positioned with respect to a first of said members and with respect to the threads of a second of said members such that when said members are moved in said one rotational direction into said assembled position, the threads of said second member are moved into the material of said peripheral retainer to deform the same and thereby form an interference fit to resist relative rotational movement between said members in a direction opposite to said one rotational direction, wherein said peripheral retainer and said first member include interengaging surfaces that prevent substantial relative rotational movement, and wherein the peripheral retainer is removable from the first member.