WHEELCHAIR WITH SUSPENSION

• US 20100004820A1
• Filed: 02/07/2008
• Published: 01/07/2010
• Est. Priority Date: 02/14/2007
• Status: Active Grant

• Current Assignee: Invacare Corporation
• Original Assignee: Invacare Corporation
• Inventors: Jurkiewicz, Damon, Fought, Gerald, Bekoscke, Robert
• Granted Patent: US 8,910,975 B2
• Time in Patent Office: Days
• US Class Current: 701/38
• CPC Class Codes: A61G 5/043 Mid wheel drive
• CPC Class Codes: A61G 5/06 with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps
• CPC Class Codes: A61G 5/10 Parts, details or accessories
• CPC Class Codes: A61G 5/1078 with shock absorbers or other suspension arrangements between wheels and frame
• CPC Class Codes: A61G 5/1089 Anti-tip devices
• CPC Class Codes: B60G 17/005 Suspension locking arrangements for retractable wheels B62D61/12
• CPC Class Codes: B60G 21/005 transversally
• CPC Class Codes: B60G 21/04 mechanically
• CPC Class Codes: B60G 2204/46 Means for locking the suspension
• CPC Class Codes: B60G 2204/4605 hydraulically, e.g. interrupting communication between the chambers of a hydraulic cylinder
• CPC Class Codes: B60G 2300/24 Wheelchairs
• CPC Class Codes: B60G 2300/402 Extra load carrying wheels, e.g. tag axles
• CPC Class Codes: Y10S 180/907 Motorized wheelchairs

Abstract

Embodiments of a suspension for a vehicle is provided. The suspension includes, for example, a frame and a locking assembly. The locking assembly inhibits tipping of a frame of the vehicle when tipping of the frame is detected.

Claims

1. A method of controlling tipping of a wheelchair frame based on downward movement of first and second rear casters with respect to the wheelchair frame comprising:

allowing upward and downward movement of first and second front casters relative to the frame when the first and second rear casters are in normal operating positions relative to the frame;

allowing upward and downward movement of the first and second front casters relative to the frame when one of the rear casters moves downward from a normal operating position relative to the frame;

inhibiting upward movement of the first and second front casters relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

2. The method of claim 1 wherein inhibiting upward movement of the first and second front casters relative to the frame comprises locking the first and second front casters against upward movement relative to the frame.

3. The method of claim 1 further comprising allowing downward movement of the first front caster and the second front caster relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

4. The method of claim 1 further comprising biasing the first front caster and the second front caster downward relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

5. The method of claim 1 further comprising locking the first front caster and the second front caster against downward movement relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

6. The method of claim 1 further comprising unlocking the first front caster and the second front caster to allow upward movement of the first front caster and the second front caster relative to the frame when one or more of the rear casters return to a normal operating position relative to the frame.

7. The method of claim 1 further comprising damping upward movement of the first and second front casters relative to the frame when one or more of the rear casters are in a normal operating position relative to the frame.

8. The method of claim 1 further comprising sensing the positions of the first and second rear casters to determine whether the first and second rear casters are in a normal operating position relative to the frame.

9. A method of controlling tipping of a wheelchair frame based on downward movement of first and second rear casters with respect to the wheelchair frame comprising:

locking the first front caster and the second front caster against upward movement relative to the frame when both of the rear casters move downward from normal operating positions relative to the frame;

allowing upward movement of both the first front caster and the second front caster relative to the frame when one of the rear casters return to a normal operating position relative to the frame.

10. The method of claim 9 further comprising allowing downward movement of the first front caster and the second front caster relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

12. The method of claim 9 further comprising locking the first front caster and the second front caster against downward movement relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

14. The method of claim 9 further comprising sensing the positions of the first and second rear casters to determine whether the first and second rear casters are in a normal operating position relative to the frame.

19. The wheelchair of claim 14 wherein the spring returns force the front casters downward with respect to the frame when the stabilizing assembly is engaged.

11. (canceled)

13. (canceled)

15. A wheelchair comprising:

a seat;

a pair of drive wheels supporting the seat;

a first front caster coupled to the seat such that the first front caster is moveable upwardly and downwardly with respect to the seat;

a second front caster coupled to the seat such that the second front caster is moveable upwardly and downwardly with respect to the seat;

a first rear caster coupled to the seat such that the first rear caster is moveable upwardly and downwardly with respect to the seat;

a second rear caster coupled to the seat such that the second rear caster is moveable upwardly and downwardly with respect to the seat;

at least one stabilizing assembly coupled to the first and second front casters;

at least one trigger that controls the stabilizing assembly configured to sense positions of the first and second rear casters;

wherein the trigger causes the stabilizing assembly to enter a disengaged state and where the stabilizing assembly allows upward and downward movement of the first front caster and the second front caster relative to the frame when the first rear caster moves downward from a normal operating position relative to the frame and the second rear caster is in a normal operating position relative to the frame; and

wherein the trigger causes the stabilizing assembly to enter an engaged state where upward movement of the first front caster and the second front caster relative to the frame is inhibited when both of the rear casters move downward from normal operating positions relative to the frame.

16. The wheelchair of claim 15 wherein the at least one stabilizing assembly comprises a first stabilizing mechanism coupled to the first front caster and a second stabilizing mechanism coupled to the second front caster.

17. The wheelchair of claim 16 wherein the first and second stabilizing mechanisms each comprise stabilizing cylinders.

18. The wheelchair of claim 17 wherein each stabilizing cylinder includes a spring return that forces each of the front casters downward with respect to the frame.

20. The wheelchair of claim 17 wherein the stabilizing cylinders damp upward movement of the front casters relative to the frame when the stabilizing assembly is disengaged.

22. The wheelchair of claim 16 wherein the first and second stabilizing mechanisms are coupled such that both stabilizing mechanisms are disengaged when the first rear caster moves downward from a normal operating position relative to the frame and the second rear caster remains in a normal operating position relative to the frame and both stabilizing mechanisms are engaged when both of the rear casters move downward from normal operating positions relative to the frame.

23. The wheelchair of claim 22 wherein the first and second stabilizing mechanisms are mechanically coupled.

24. The wheelchair of claim 22 wherein the first and second stabilizing mechanisms are coupled by a bar that rotates with respect to the first and second stabilizing mechanisms when the both of the rear casters move downwardly with respect to the frame.

26. The wheelchair of claim 22 wherein the first and second stabilizing mechanisms are coupled by a hydraulic connection.

27. The wheelchair of claim 22 wherein the first and second stabilizing mechanisms are electronically coupled.

28. The wheelchair of claim 15 wherein the stabilizing assembly comprises a single stabilizing mechanism coupled to both of the front casters.

30. The wheelchair of claim 15 wherein the stabilizing assembly allows downward movement of the first front caster and the second front caster relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

31. The wheelchair of claim 15 wherein the stabilizing assembly biases the first front caster and the second front caster downward relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

32. The wheelchair of claim 15 wherein the stabilizing assembly locks the first front caster and the second front caster against downward movement relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

33. The wheelchair of claim 15 wherein the stabilizing assembly allows upward movement of the first front caster and the second front caster relative to the frame when one or more of the rear casters return to a normal operating position relative to the frame.

21. (canceled)

25. (canceled)

29. (canceled)

34. (canceled)

35. (canceled)

36. (canceled)

37. (canceled)

38. (canceled)

39. (canceled)

40. A wheelchair comprising:

a frame;

a seat supported by the frame;

a pair of drive wheels supporting the frame;

a first front caster coupled to the frame such that the first front caster is moveable upwardly and downwardly with respect to the frame;

a second front caster coupled to the frame such that the second front caster is moveable upwardly and downwardly with respect to the frame;

a first rear caster coupled to the frame such that the first rear caster is moveable upwardly and downwardly with respect to the frame;

a second rear caster coupled to the frame such that the second rear caster is moveable upwardly and downwardly with respect to the frame;

a stabilizing assembly coupled to the first and second front casters;

a trigger in communication with the stabilizing assembly;

wherein the stabilizing assembly inhibits the first front caster and the second front caster from moving upward relative to the frame when the trigger senses that both of the rear casters have moved downward from normal operating positions relative to the frame; and

wherein the stabilizing assembly allows upward movement of the first front caster and the second front caster relative to the frame when the trigger senses that one or more of the rear casters have returned to a normal operating position relative to the frame.

41. The wheelchair of claim 40 wherein the stabilizing assembly comprises a first stabilizing mechanism coupled to the first front caster and a second stabilizing mechanism coupled to the second front caster.

53. The wheelchair of claim 40 wherein the stabilizing assembly comprises a single stabilizing mechanism coupled to both of the front casters.

57. The wheelchair of claim 40 wherein the stabilizing assembly locks the first front caster and the second front caster against downward movement relative to the frame when both of the rear casters move downward from the normal operating positions relative to the frame.

42. (canceled)

46. The wheelchair of claim 42 wherein the stabilizing cylinders allow downward movement of the front casters with respect to the frame when the stabilizing assembly is engaged.

43. (canceled)

44. (canceled)

45. (canceled)

47. (canceled)

48. (canceled)

49. (canceled)

50. (canceled)

51. (canceled)

52. (canceled)

54. (canceled)

55. (canceled)

56. (canceled)

58. (canceled)

59. (canceled)

60. (canceled)

61. (canceled)

62. (canceled)

63. (canceled)

64. (canceled)

65. (canceled)

66. (canceled)

67. (canceled)

68. (canceled)

69. (canceled)

70. (canceled)

71. (canceled)

72. (canceled)

73. (canceled)

74. (canceled)

75. (canceled)

76. (canceled)

77. (canceled)

78. (canceled)

79. (canceled)

80. (canceled)

81. (canceled)

82. (canceled)

83. (canceled)

84. (canceled)

85. (canceled)

86. (canceled)

87. (canceled)

88. (canceled)

89. (canceled)

90. (canceled)

91. (canceled)

92. (canceled)

93. (canceled)