Resilient wheel structure

• US 6,615,885 B1
• Filed: 10/29/2001
• Issued: 09/09/2003
• Est. Priority Date: 10/31/2000
• Status: Expired due to Term

• Current Assignee: Flir Detection, Inc. (Teledyne Technologies Incorporated)
• Original Assignee: iRobot Corporation
• Inventors: Ohm, Timothy R.
• Primary Examiner(s): Stormer, Russell D.
• Application Number:
  US10/055,314
• Time in Patent Office: 680 Days
• Field of Search: 152/1, 152/5, 152/6, 152/7, 152/11, 152/12, 152/17, 152/31, 152/69, 152/75, 152/80, 152/85, 152/86
• US Class Current: 152/11
• CPC Class Codes: B60B 9/26 comprising resilient spokes

Abstract

A resilient wheel structure having a rim and a hub interconnected by spokes, wherein the rim is sufficiently stiff to distribute a load to all of the spokes, and wherein the wheel is able to absorb loads in both the radial and axial directions. The rim comprises an inner and outer rim portion supported by ribs, that are located co-radially with curved spokes that allow tension and compression. The wheel structure being optimally used on a mobile robot.

Claims

1. A wheel structure comprising:

a continuous, annular rim;

a hub;

and a plurality of spokes interconnecting said rim and said hub;

each of said spokes possessing a first spoke portion integrally connected to the hub at a hub origin point, a second spoke portion integrally connected to said rim at a rim origin point, and a third spoke portion integrally connected to said first spoke portion and integrally connected to said second spoke portion;

said third spoke portion extending in generally different direction than said first spoke portion;

the rim further comprising an outer annular rim, an inner annular rim, rib interconnecting said outer rim to said inner rim, the inner annular rim and the outer annular rim being more rigid than at least one of the plurality spokes.

2. The wheel structure of claim 1 in which said rim further comprises a plurality of ribs interconnecting said outer rim to said inner rim.

3. The wheel structure of claim 2, wherein said plurality of ribs are substantially equispaced.

4. The wheel structure of claim 2 in which said rim further comprises a center wall connecting said outer rim to said inner rim, said center wall substantially perpendicular to said inner rim and to said outer rim, wherein said center wall is integrally connected to the plurality of ribs.

5. The wheel structure of claim 4 wherein said third spoke portion extends in a generally different direction than said second spoke portion.

6. The wheel structure of claim 5, wherein the hub origin point is co-radial with the rim origin point.

7. The wheel structure of claim 6, wherein the hub origin point is co-radial with a rib.

8. The wheel structure of claim 7 comprising an equivalent number of spokes and ribs.

9. The wheel structure of claim 8 comprising from 10 to 25 spokes.

10. The wheel structure of claim 5 wherein the plurality of spokes are spaced such that the spokes cannot come into contact with one another during compression.

11. The wheel structure of claim 7, wherein the outer rim comprises an outer surface and an inner surface, and said outer surface further comprises cleats for engaging cogs on a track.

12. The wheel structure of claim 11 wherein the wheel structure is constructed from a polymeric material.

13. The wheel structure of claim 12 wherein the wheel structure is constructed from cast polyurethane.

14. The wheel structure of claim 12 wherein the wheel structure is constructed from Nylon.

15. The wheel structure of claim 11, wherein said rim is constructed from metal and said spokes are constructed from a polymeric material.

16. The wheel structure of claim 5, further comprising a filler material positioned between any two of said spokes.

17. The wheel structure of claim 16, wherein the filler material is polyurethane.

18. The wheel structure of claim 16, wherein the hub origin point is co-radial with the rim origin point.

19. The wheel structure of claim 18, wherein the hub origin point is co-radial with a rib.

20. The wheel structure of claim 19 comprising an equivalent number of spokes and ribs.

21. The wheel structure of claim 20 comprising from 10 to 25 spokes.

22. The wheel structure of claim 21, wherein said outer rim comprises an outer surface and an inner surface, and said outer surface further comprises cleats for engaging cogs on a track.

23. The wheel structure of claim 5, wherein said third spoke portion is at least three times as long as said first spoke portion.

24. The wheel structure of claim 5, wherein said third spoke portion is at least four times as long as said second spoke portion.

25. A wheel structure for a mobile robot, comprising:

a continuous, annular rim;

a hub; and

a plurality of spokes interconnecting said rim and said hub;

each of said spokes possessing a first spoke portion integrally connected to the hub at a hub origin point, a second spoke portion integrally connected to said rim at a rim origin point, and a third spoke portion integrally connected to said first spoke portion and integrally connected to said second spoke portion;

said third spoke portion extending in generally different direction than said first spoke portion;

the rim further comprising an outer annular rim, an inner annular rim, and a rib interconnecting said outer rim to said inner rim, the inner annular rim and the outer annular rim being more rigid than at least one of the plurality spokes;

wherein said rim further comprises a plurality of ribs interconnecting said outer rim to said inner rim;

wherein said wheel structure is mounted to a mobile robot.

35. The wheel structure of claim 25, wherein the outer annular rim comprises an outer surface and an inner surface, and the outer surface further comprises cleats for engaging cogs on a track.

36. The wheel structure of claim 25, wherein the wheel structure is constructed from a polymeric material.

37. The wheel structure of claim 25, wherein the wheel structure is constructed from cast polyurethane.

38. The wheel structure of claim 25, wherein the wheel structure is constructed from Nylon.

39. The wheel structure of claim 25, wherein the rim is constructed from metal and the spokes are constructed from a polymeric material.

40. The wheel structure of claim 25, further comprising a filler material positioned between any two of the spokes.

41. The wheel structure of claim 25, wherein the filler material comprises polyurethane.

42. The wheel structure of claim 25, wherein the hub origin point is co-radial with the rim origin point.

43. The wheel structure of claim 25, wherein the hub origin point is co-radial with a rib.

44. The wheel structure of claim 25, wherein there are an equivalent number of spokes and ribs.

45. The wheel structure of claim 25, wherein there area from 10 to 25 spokes.

46. The wheel structure of claim 25, wherein the outer annular rim comprises all outer surface and an inner surface, and the outer surface further comprises cleats for engaging cogs on a track.

47. The wheel structure of claim 25, wherein the third spoke portion is at least three times as long as the first spoke portion.

48. The wheel structure of claim 25, wherein the third spoke portion is at least four times as long as the second spoke portion.

26. A wheel structure comprising:

a hub;

a continuous, annular rim comprising an outer annular rim, an inner annular rim, and ribs interconnecting the outer annular rim to the inner annular rim; and

spokes interconnecting the rim and the hub;

each of the spokes comprising a first spoke portion integrally connected to the hub at a hub origin point, a second spoke portion integrally connected to the rim at a rim origin point, and a third spoke portion integrally connected to the first spoke portion and integrally connected to the second spoke portion, the third spoke portion extending in generally different direction than the first spoke portion, locations of the spokes along a circumference of the inner annular rim rim corresponding to locations of the ribs along the circumference.

27. The wheel structure of claim 26, wherein the ribs are substantially equispaced.

28. The wheel structure of claim 26, wherein the rim further comprises a center wall connecting the outer annular rim to the inner annular rim, the center wall being substantially perpendicular to the inner annular rim and to the outer annular rim, the center wall being integrally connected to the ribs.

29. The wheel structure of claim 28, wherein the third spoke portion extends in a generally different direction than the second spoke portion.

30. The wheel structure of claim 29, wherein the hub origin point is co-radial with the rim origin point.

31. The wheel structure of, claim 30, wherein the hub origin point is co-radial with a rib.

32. The wheel structure of claim 31, wherein there are an equivalent number of spokes and ribs.

33. The wheel structure of claim 32, wherein there are from 10 to 25 spokes.

34. The wheel structure of claim 27, wherein the spokes are spaced such that the spokes cannot come into contact with one another during compression.