Piston-piston rod retaining assembly for a hydraulic piston and cylinder unit

• US 20060032369A1
• Filed: 08/13/2004
• Published: 02/16/2006
• Est. Priority Date: 08/13/2004
• Status: Active Grant

• Current Assignee: Stanley Works Limited (Stanley Black & Decker, Inc.)
• Original Assignee: Stanley Works Limited (Stanley Black & Decker, Inc.)
• Inventors: Rafn, Mark D.
• Granted Patent: US 7,322,273 B2
• Time in Patent Office: Days
• US Class Current: 92/128
• CPC Class Codes: F15B 15/1447 Pistons; Piston to piston rod assemblies
• CPC Class Codes: F15B 15/149 Fluid interconnections, e.g. fluid connectors, passages

Abstract

A hydraulic piston and cylinder unit comprising the combination of a cylinder assembly defining a cylindrical chamber, a piston member mounted in the cylindrical chamber for reciprocating movement therein in response to movement of hydraulic fluid under pressure into and out of the chamber, and a piston rod member connected to the piston member for movement therewith and extending from one end of cylinder assembly. The members have meshing threads thereon configured to be meshingly interengaged when the members are rotationally moved into an assembled position relative to one another in one direction. The combination also includes a retaining ring including deformable material configured and positioned with respect to one of the members and with respect to the threads of another of the members such that when the members are moved in the one rotational direction into the assembled position, the threads of the other member are moved into the material of the retaining ring to deform the same and thereby resist relative rotational movement between the members in the opposite direction.

Claims

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 retaining ring including deformable material configured and positioned with respect to one of said members and with respect to the threads of the other of said members such that when said members are moved in said one rotational direction into said assembled position, the threads of said other member are moved into the material of said retaining ring to deform the same and thereby resist relative rotational movement between said members in a direction opposite to said one rotational direction.

2. A hydraulic piston and cylinder unit as defined in claim 1, wherein said retaining ring is mounted on said one member against relative axial movement in at least one direction beyond an operatively mounted position and against substantial relative rotational movement in either direction.

3. A hydraulic piston and cylinder unit as defined in claim 2, wherein said retaining ring is mounted on said one member against substantial relative axial movement in either direction.

4. A hydraulic piston and cylinder unit as defined in claim 2, wherein said retaining ring and said one member include a series of annularly spaced interengaging projections and recesses preventing said substantial relative rotational movement.

5. A hydraulic piston and cylinder unit as defined in claim 4, wherein said one member includes a series of annularly-spaced radially extending lugs configured and positioned to engage said retaining ring and prevent said axial movement in said one direction beyond said operatively mounted position.

6. A hydraulic piston and cylinder unit as defined in claim 5, wherein the material of said retaining ring forms the entirety of said retaining ring.

7. A hydraulic piston and cylinder unit as defined in claim 6, wherein the material of said retaining ring is urethane.

8. A hydraulic piston and cylinder unit as defined in claim 7, wherein said one member constitutes said piston member and said series of ancillaryly-spaced recesses are formed in said piston member.

9. A hydraulic piston and cylinder unit as defined in claim 1, wherein the material of said retaining ring is urethane and forms the entirely of said retaining ring.

10. A hydraulic piston and cylinder unit as defined in claim 1, wherein said one member constitutes said piston member.

11. A hydraulic piston and cylinder unit as defined in claim 1, wherein said members include stop surfaces which interengage when said members are moved into said assembled position.

12. A hydraulic piston and cylinder unit as defined in claim 11, wherein said stop surfaces are frusto-conical.

13. A piston and piston rod assembly comprising:

a piston member;

a piston rod member;

said members having meshing threads thereon configured to be meshingly interengaged when said members are rotationally moved into an assembled position relative to one another in one direction; and

a retaining ring including deformable material configured and positioned with respect to one of said member and with respect to the threads of another of said members such that when said members are moved in said one rotational direction into said assembled position, the threads of said other member are moved into the material of said retaining ring to deform the same and thereby resist relative rotational movement between said members in the opposite direction.

14. A piston and piston rod assembly as defined in claim 13, wherein said retaining ring is mounted on said one member against relative axial movement in at least one direction beyond an operatively mounted position and against substantial relative rotational movement in either direction.

15. A piston and piston rod assembly as defined in claim 13, wherein said retaining ring and said one member include a series of annularly spaced interengaging projections and recesses preventing said substantial relative rotational movement.

16. A piston and piston rod assembly as defined in claim 15, wherein said one member includes a series of annularly spaced radially extending lugs configured and positioned to engage said retaining ring and prevent said axial movement in said one direction beyond said operatively mounted position.

17. A piston and piston rod assembly as defined in claim 16, wherein said one member constitutes said piston member and said series of ancillaryly-spaced recesses are formed in said piston member.

18. A piston and piston rod assembly as defined in claim 13, wherein the material of said retaining ring is urethane and forms the entirely of said retaining ring.

19. A piston and piston rod assembly as defined in claim 13, wherein said one member constitutes said piston member.

20. A piston and piston rod assembly as defined in claim 13, wherein said members include stop surfaces which interengage when said members are moved into said assembled position.