Linked suspension system for a vehicle

• US 6,976,689 B2
• Filed: 11/02/2001
• Issued: 12/20/2005
• Est. Priority Date: 11/03/2000
• Status: Expired due to Term

• Current Assignee: Arctic Cat Incorporated (Textron Inc)
• Original Assignee: Arctic Cat Incorporated (Textron Inc)
• Inventors: Hibbert, Kirk
• Primary Examiner(s): Dickson, Paul N.
• Assistant Examiner(s): To, Toan C
• Application Number:
  US10/008,455
• Publication Number:
  US 20020093168A1
• Time in Patent Office: 1,509 Days
• Field of Search: 180/190, 180/191, 180/193, 280/124.154, 280/124.157, 280/124.158, 280/124.159, 280/124.161, 280/124.151, 280/124.116, 267/64.11, 267/64.13, 267/64.14
• US Class Current: 280/124.159
• CPC Class Codes: B60G 21/06 fluid
• CPC Class Codes: B60G 2202/154 with an accumulator
• CPC Class Codes: B60G 2204/8304 using a fluid
• CPC Class Codes: B62D 55/112 with fluid springs, e.g. hydraulic pneumatic

Abstract

A suspension system for a vehicle, having at least first and second shock absorbers. The first shock absorber has a first main piston, and the second shock absorber has a second main piston. The shock absorbers are motively linked such that when the first main piston retracts, the second main piston is also caused to retract. The first and second shock absorbers may be hydraulic shock absorbers, wherein the first shock absorber defines a first hydraulic chamber therein, and the second shock absorber defines a second hydraulic chamber therein, the first and second hydraulic chambers being connected with a hydraulic line, so that causing the first main piston to retract reduces the size of the first hydraulic chamber, which increases the size of the second hydraulic chamber, which then causes the second main piston to retract. The suspension system may include an adjustor for convenient adjusting of the suspension system. The suspension system may include a remote reservoir to accommodate changes in the volumes of the first and second hydraulic chambers.

Claims

1. A vehicle suspension system, comprising

a first shock absorber comprising a first main piston disposed therein, said first main piston being moveable between a retracted position wherein said first main piston is substantially retracted within said first shock absorber and an extended position wherein said first main piston is at least partially extended from said first shock absorber;

a second shock absorber comprising a second main piston disposed therein, said second main piston being moveable between a retracted position wherein said second main piston is substantially retracted within said second shock absorber and an extended position wherein said second main piston is at least partially extended from said first shock absorber;

wherein said first and second shock absorbers motively linked with one another whereby when said first main piston is moved toward said retracted position, said second main piston is caused to move toward said retracted position;

said first shock absorber is a hydraulic shock absorber defining a first hydraulic chamber therein, wherein a volume of said first hydraulic chamber is smaller when said first main piston is in said retracted position than when said first main piston is in said extended position;

said second shock absorber is a hydraulic shock absorber defining a second hydraulic chamber therein, wherein increasing a volume of said second hydraulic chamber causes said second main piston to move toward said retracted position; and

said second hydraulic chamber being in hydraulic communication with said first hydraulic chamber, wherein decreasing said volume of said first hydraulic chamber increases said volume of said second hydraulic chamber;

an adjustor comprising an adjustor piston disposed at least partially in said adjustor, said adjustor piston being moveable between a retracted position wherein said adjustor piston is substantially retracted within said adjustor and an extended position wherein said adjustor piston is at least partially said adjustor piston adjusts a neutral position of said second main piston;

whereby when said first main piston is moved towards said retracted position, said volume of said first hydraulic chamber is decreased, whereby said volume of said second hydraulic chamber is increased, whereby said second main piston moves toward said retracted position.

2. The vehicle suspension system according to claim 1, wherein

said second shock absorber defines a third hydraulic chamber therein adjacent to said second hydraulic chamber, wherein increasing said volume of said second hydraulic chamber decreases a volume of said third hydraulic chamber.

3. The vehicle suspension system according to claim 2, further comprising

a remote reservoir mechanism adapted to accommodate motions of said first and second main pistons, said remote reservoir mechanism comprising a remote reservoir piston at least partially disposed in said remote reservoir mechanism, said remote reservoir piston being moveable between a retracted position wherein said remote reservoir piston is substantially retracted within said remote reservoir mechanism and an extended position wherein said remote reservoir piston is at least partially extended from said remote reservoir mechanism;

said remote reservoir mechanism defining a fifth hydraulic chamber therein in hydraulic communication with said third hydraulic chamber, such that decreasing said volume of said third hydraulic chamber increases a volume of said fifth hydraulic chamber;

said remote reservoir mechanism defining a pressure means chamber therein in communication with said fifth hydraulic chamber, such that increasing said volume of said fifth hydraulic chamber decreases a volume of said pressure means chamber.

4. The vehicle suspension system according to claim 3, wherein said remote reservoir mechanism comprises at least one o-ring.

5. The vehicle suspension system according to claim 4, wherein

said at least one o-ring comprises at least one of the group consisting of nitrile and fluoroelastomer.

6. The vehicle suspension system according to claim 3, further comprising

a bleed-back valve between said third and fifth hydraulic chambers, said bleed-back valve being adapted to control fluid communication between said third and fifth hydraulic chambers.

7. The vehicle suspension system according to claim 2, wherein

said second hydraulic chamber defines central portion and a passage portion disposed peripherally to said central portion, said passage portion being in hydraulic communication with said first hydraulic chamber, said central portion being in hydraulic communication with said passage portion.

8. The vehicle suspension system according to claim 7, wherein

said passage portion comprises a plurality of tubes.

9. The vehicle suspension system according to claim 8, wherein

said tubes are approximately 0.160 inches in diameter.

10. The vehicle suspension system according to claim 7, wherein

said passage portion comprises one tube.

11. The vehicle suspension system according to claim 7, wherein

said passage portion comprises a cylindrical shell.

12. The vehicle suspension system according to claim 7, further comprising

a first hydraulic line connecting said first hydraulic chamber and said passage portion of said second hydraulic chamber.

13. The vehicle suspension system according to claim 3, further comprising

a third hydraulic line connecting said third and fifth hydraulic chambers.

14. The vehicle suspension system according to claim 3, wherein

said third and fifth hydraulic chambers are substantially filled with a second hydraulic fluid.

15. The vehicle suspension system according to claim 14, wherein

said second hydraulic fluid is synthetic hydraulic oil.

16. The vehicle suspension system according to claim 3, wherein

said pressure means chamber is substantially filled with a second pneumatic fluid.

17. The vehicle suspension system according to claim 16, wherein

said second pneumatic fluid is compressed nitrogen.

18. The vehicle suspension system according to claim 16, wherein

said second pneumatic fluid is compressed air.

19. The vehicle suspension system according to claim 1, wherein

said adjustor defines a fourth hydraulic chamber therein in fluid communication with said first and second hydraulic chambers such that changing a volume of said fourth hydraulic chamber changes at least one of said volumes of said first hydraulic chambers.

20. The vehicle suspension system according to claim 19, wherein

moving said adjustor piston toward said retracted position decreases a volume of said fourth hydraulic chamber;

and

decreasing a volume of said fourth hydraulic chamber increases said volume of said second hydraulic chamber, such that said separator piston moves towards said second main piston, whereby said second main piston moves towards said retracted position thereof.

21. The vehicle suspension system according to claim 19, wherein

said adjustor defines a first pneumatic chamber therein adjacent to said fourth hydraulic chamber, such that increasing a volume of said first pneumatic chamber decreases a volume of said fourth hydraulic chamber;

and

decreasing a volume of said fourth hydraulic chamber increases said volume of said first hydraulic chamber, such that said first main piston moves towards said extended position thereof, whereby said second main piston moves towards said retracted position thereof.

22. The vehicle suspension system according to claim 21, wherein

said first pneumatic chamber is substantially filled with a first pneumatic fluid.

23. The vehicle suspension system according to claim 22, wherein

said first pneumatic fluid is air.

24. The vehicle suspension system according to claim 19, further comprising

a second hydraulic line connecting said second and fourth hydraulic chambers.

25. The vehicle suspension system according to claim 19, wherein

said adjustor comprises at least one o-ring.

26. The vehicle suspension system according to claim 25, wherein

said at least one o-ring comprises at least one of the group consisting of nitrile and fluoroelastomer.

27. The vehicle suspension system according to claim 1, further comprising

a first hydraulic line connecting said first and second hydraulic chambers.

28. The vehicle suspension system according to claim 1, wherein

said first, second, and fourth hydraulic chambers are substantially filled with a first hydraulic fluid.

29. The vehicle suspension system according to claim 28, wherein

said first hydraulic fluid is synthetic hydraulic oil.

30. The vehicle suspension system according to claim 1, wherein

at least one of said first and second shock absorbers comprises at least one o-ring.

31. The vehicle suspension system according to claim 30, wherein

said at least one o-ring comprises at least one of the group consisting of nitrile and fluoroelastomer.

32. The vehicle suspension system according to claim 1, further comprising a restrictor between said first and second hydraulic chambers, said restrictor being adapted to control fluid communication between said first and second hydraulic chambers.

33. A vehicle suspension system, comprising

a first hydraulic shock absorber comprising a first main piston at least partially disposed therein, said first main piston defining a first hydraulic chamber, said first main piston being moveable between a retracted position wherein said first main piston is substantially retracted within said first shock absorber to reduce a volume of said first hydraulic chamber, and an extended position wherein said first main piston is at least partially extended from said first shock absorber to expand said volume of said first hydraulic chamber;

and

a second hydraulic shock absorber comprising a second main piston disposed therein and a separator piston disposed therein, said second main piston being moveable between a retracted position wherein said second main piston is substantially retracted within said second shock absorber and an extended position wherein said second main piston is at least partially extended from said first shock absorber, said separator piston being axially spaced apart from said second main piston and defining second and third hydraulic chambers within said second hydraulic shock absorber, said second main piston being positioned within said third hydraulic chamber, said second hydraulic chamber decreasing in volume and said third hydraulic chamber increasing in volume as said second main piston moves to said extended position, and said second hydraulic chamber increasing in volume and said third hydraulic chamber decreasing in volume as said second main piston moves to said extended position;

wherein said first and second hydraulic chambers are in fluid communication with one another whereby when said first main piston is moved toward said retracted position, said second main piston is caused to move toward said retracted position; and

wherein said second and third hydraulic chambers are isolated from each other.

34. The system of claim 33, wherein said first main piston comprises a first damping valve, such that fluid within said first hydraulic shock absorber moves through said first damping valve as said first main piston moves between said extended and said retracted positions in such a fashion as to minimize cavitation of said fluid and said second main piston comprises a second damping valve, such that fluid within said second hydraulic chamber moves through said second damping valve as said second main piston moves between said extended and retracted positions in such a fashion as to minimize cavitation of said fluid.

35. A vehicle suspension system, comprising:

a first hydraulic shock absorber comprising a first main piston at least partially disposed therein, said first main piston being moveable between a retracted position wherein said first main piston is substantially retracted within said first shock absorber and an extended position wherein said first main piston is at least partially extended from said first shock absorber,

a second hydraulic shock absorber comprising a second main piston at least partially disposed therein, said second main piston being moveable between a refracted position wherein said second main piston is substantially retracted within said second shock absorber and an extended position wherein said second main piston is at least partially extended from said first shock absorber, and

an adjustor comprising an adjustor piston disposed at least partially in said adjustor, said adjustor piston being moveable between a retracted position wherein said adjustor piston is substantially retracted within said adjustor and an extended position wherein said adjustor piston is at least partially extended from said adjustor;

wherein said first and second shock absorbers are motively linked with one another whereby when said first main piston is moved toward said retracted position, said second main piston is caused to move toward said retracted position; and

wherein moving said adjustor piston adjusts a neutral position of said second main piston.

36. The vehicle suspension system according to claim 35, wherein said first and second main pistons are in phase, such that when said first main piston moves towards said retracted position, said second main piston moves towards said retracted position.

37. The vehicle suspension system according to claim 35, further comprising a remote reservoir mechanism adapted to accommodate motions of said first and second main pistons.

38. The vehicle suspension system according to claim 35, wherein said

first and second shock absorbers comprise hydraulic fluid therein.

39. The vehicle suspension system according to claim 38, wherein said hydraulic fluid is synthetic hydraulic oil.

40. The vehicle suspension system according to claim 38, wherein said hydraulic fluid is a medium-weight hydraulic oil.

41. The vehicle suspension system according to claim 38, wherein said hydraulic fluid is a light-weight hydraulic oil.

42. The vehicle suspension system according to claim 38, wherein said vehicle suspension system is adapted to substantially avoid cavitation of said hydraulic fluid.

43. The vehicle suspension system according to claim 38, wherein said vehicle suspension system is adapted to be operable during cavitation of said hydraulic fluid.

44. A vehicle suspension system, comprising

a first shock absorber comprising a first main piston disposed therein, said first main piston being moveable between a retracted position wherein said first main piston is substantially retracted within said first shock absorber and an extended position wherein said first main piston is at least partially extended from said first shock absorber;

a second shock absorber comprising a second main piston disposed therein, said second main piston being moveable between a refracted position wherein said second main piston is substantially retracted within said second shock absorber and an extended position wherein said second main piston is at least partially extended from said first shock absorber,

wherein said first and second shock absorbers motively linked with one another whereby when said first main piston is moved toward said retracted position, said second main piston is caused to move toward said retracted position;

said first shock absorber is a hydraulic shock absorber defining a first hydraulic chamber therein, wherein a volume of said first hydraulic chamber is smaller when said first main piston is in said retracted position than when said first main piston is in said extended position;

said second shock absorber is a hydraulic shook absorber defining a second hydraulic chamber therein and a third hydraulic chamber therein adjacent to said second hydraulic chamber, wherein increasing a volume of said second hydraulic chamber causes said second main piston to move toward said retracted position and decrease a volume of said third hydraulic chamber;

said second hydraulic chamber being in hydraulic communication with said first hydraulic chamber, wherein decreasing said volume of said first hydraulic chamber increases said volume of said second hydraulic chamber; and

said second hydraulic chamber defines central portion and a passage portion disposed peripherally to said central portion, said passage portion being in hydraulic communication with said first hydraulic chamber, said central portion being in hydraulic communication with said passage portion;

whereby when said first main piston is moved towards said retracted position, said volume of said first hydraulic chamber is decreased, whereby said volume of said second hydraulic chamber is increased, whereby said second main piston moves toward said retracted position.

45. The vehicle suspension system according to claim 44, wherein

said passage portion comprises a plurality of tubes.

46. The vehicle suspension system according to claim 44, wherein

said passage portion comprises a cylindrical shell.