Jack assembly

1. A jack assembly comprising:

a first tube having first and second end portions and a central portion between said first and second end portions;

a second tube positioned within said first tube and movable with respect to said first tube;

an expanded portion on said first tube, said expanded portion having a larger inner diameter than an inner diameter of said central portion; and

a bushing attached to said expanded portion, wherein said bushing generally prevents contact between said first and second tubes.

2. The jack assembly of claim 1 , wherein said expanded portion is located at either of said first end or said second end of said first tube.

3. The jack assembly of claim 1 , further comprising an engaging feature in a side of said first tube and an engaging member on said bushing, wherein said engaging feature engages said engaging member retaining said bushing to said expanded portion.

4. The jack assembly of claim 3 , wherein said engaging member comprises a protrusion in said bushing.

5. The jack assembly of claim 1 , wherein said bushing includes at least one drain slot positioned on said bushing, said drain slot extending from an upper surface to a lower surface of said bushing along an inner side wall of said bushing.

6. The jack assembly of claim 1 , wherein an inner surface of said bushing is a discontinuous surface.

7. The jack assembly of claim 1 , wherein said second tube includes an outer sidewall in direct contact with said bushing as said second tube moves relative to said first tube.

8. A jack assembly comprising:

a first tube;

a second tube positioned within said first tube and movable with respect to said first tube;

a screw disposed within said second tube;

a nut rotationally fixed relative to said second tube and threadingly engaged with said screw; and

a bushing positioned within an opening in said second tube, said bushing having an opening threadingly engaged with said screw, wherein said bushing, nut and second tube move in unison relative to said first tube and whereby said bushing generally prevents contact between said first and second tubes and wherein said bushing includes at least one recessed portion along an outer diameter of said bushing, whereby said recessed portion allows drainage.

9. The jack assembly of claim 8 , wherein said bushing includes at least one post, whereby said at least one post engages said nut and generally prevents rotation of said bushing relative to said second tube.

10. The jack assembly of claim 8 , wherein an outer diameter of said bushing is generally convex shaped thereby providing reduced contact with an inner sidewall of said first tube.

11. A jack assembly comprising:

a first tube;

a second tube positioned within said first tube and movable with respect to said first tube;

a caster assembly connected to said second tube, said caster assembly comprising:

a pin having a top surface and a sidewall;

a cage member having a surface providing vertical load support to said top surface of said pin and having a sidewall that generally circumscribes at least a portion of said sidewall of said pin, wherein said pin is rotatable relative to said cage member; and

a bushing positioned between said sidewall of said pin and said sidewall of said cage member.

12. The jack assembly of claim 11 , wherein said cage member is configured to engage with a lower portion of said second tube transferring vertical load through said cage member to said second tube.

13. The jack assembly of claim 12 , wherein said cage member includes a lip portion whereby said second tube operatively engages said lip portion transferring said vertical load.

14. The jack assembly of claim 11 , wherein said surface includes a projection depending therefrom providing point contact between said cage member and said pin.

15. The jack assembly of claim 14 , wherein projection is monolithically formed with said cage member as a casting.

16. The jack assembly of claim 14 , wherein said projection provides vertical loading to said pin and allows relative rotation between said pin and said cage member.

17. The jack assembly of claim 11 , further comprising an antifriction device positioned between said top surface of said pin and said surface of said cage member.

18. The jack assembly of claim 17 , wherein said antifriction device includes a washer.

19. The jack assembly of claim 11 , wherein said cage member includes at least one relief providing drainage from said second tube.

20. The jack assembly of claim 11 , wherein second tube includes a sidewall generally free of a deformation and including a pair of opposed openings.

21. The jack assembly of claim 11 , wherein said sidewall of said cage member provides side loading support of said pin.

22. The jack assembly of claim 11 , wherein said bushing includes a tapered outer diameter and a generally non-tapered inner diameter.

23. The jack assembly of claim 22 , further comprising a support device operatively engaged with said caster assembly.

24. The jack assembly of claim 23 , wherein said bushing wedgingly secures said support device with said sleeve.

25. The jack assembly of claim 24 , wherein a moment load is applied through said bushing upon loading of said support device.

26. The jack assembly of claim 11 , wherein said cage member is tapered and configured to wedgingly engage said second tube.

27. A jack assembly comprising:

a first tube;

a second tube positioned within said first tube and movable with respect to said first tube;

a screw disposed within said second tube;

a nut rotationally fixed relative to said second tube and threadingly engaged with said screw; and

a bushing positioned within an opening in said second tube, said bushing having an opening threadingly engaged with said screw, wherein said bushing, nut and second tube move in unison relative to said first tube and whereby said bushing generally prevents contact between said first and second tubes and wherein said bushing includes a discontinuous outer sidewall whereby said discontinuous outer sidewall allows drainage.

28. A jack assembly comprising:

a first tube;

a second tube positioned within said first tube and movable with respect to said first tube;

a screw disposed within said second tube;

a nut rotationally fixed relative to said second tube and threadingly engaged with said screw; and

a bushing positioned within an opening in said second tube, said bushing having an opening threadingly engaged with said screw, wherein said bushing, nut and second tube move in unison relative to said first tube and whereby said bushing generally prevents contact between said first and second tubes and wherein a top surface of said bushing includes a chamfered portion, whereby said chamfered portion is angled toward said opening forming a funnel for fluid.

29. A jack assembly comprising:

a first tube;

a second tube positioned within said first tube and movable with respect to said first tube;

a caster assembly connected to said second tube, said caster assembly comprising:

a pin having a top surface and a sidewall;

a cage member having a surface providing vertical load support to said top surface of said pin and having a sidewall that generally circumscribes at least a portion of said sidewall of said pin, wherein said pin is rotatable relative to said cage member; and

an antifriction device positioned between said top surface of said pin and said surface of said cage member.

30. A jack assembly comprising:

a first tube;

a second tube positioned within said first tube and movable with respect to said first tube;

a caster assembly connected to said second tube, said caster assembly comprising:

a pin having a top surface and a sidewall;

a cage member having a surface providing vertical load support to said top surface of said pin and having a sidewall that generally circumscribes at least a portion of said sidewall of said pin, wherein said pin is rotatable relative to said cage member, wherein said cage member includes at least one relief providing drainage from said second tube.