Self-regulating suspension

• US 8,672,106 B2
• Filed: 10/12/2010
• Issued: 03/18/2014
• Est. Priority Date: 10/13/2009
• Status: Active Grant

• Current Assignee: Fox Factory Incorporated
• Original Assignee: Fox Factory Incorporated
• Inventors: Laird, Andrew, Becker, William
• Primary Examiner(s): Siconolfi, Robert A
• Assistant Examiner(s): AUNG, SAN M
• Application Number:
  US12/903,022
• Publication Number:
  US 20110083930A1
• Time in Patent Office: 1,253 Days
• Field of Search: 188/275, 188/314, 188/276, 188/322.13, 188/316, 188/318, 1883191-3192, 188/266.6, 188/322.2, 188/285, 188/297, 188/315, 188/322.19, 188/300, 280/284
• US Class Current: 188/275
• CPC Class Codes: B62K 25/08 for front wheel
• CPC Class Codes: F16F 13/002 comprising at least one fluid spring F16F13/005, F16F13/02, F16F13/04 take precedence
• CPC Class Codes: F16F 13/007 the damper being a fluid damper
• CPC Class Codes: F16F 9/092 comprising a gas spring with a flexible wall provided between the tubes of a bitubular damper
• CPC Class Codes: F16F 9/18 with a closed cylinder and a piston separating two or more working spaces therein
• CPC Class Codes: F16F 9/34 Special valve constructions F16F9/44, F16F9/50 take precedence; filtering details F16F9/3285 ; valves in general F16K; Shape or construction of throttling passages
• CPC Class Codes: F16F 9/363 the guide being mounted between the piston and the sealing, enabling lubrication of the guide
• CPC Class Codes: F16F 9/464 Control of valve bias or pre-stress, e.g. electromagnetically F16F9/465 takes precedence
• CPC Class Codes: F16F 9/504 Inertia , i.e. acceleration,-sensitive means

Abstract

A self-regulating suspension includes a first suspension member movable relative to a second suspension member, a fluid reservoir having a volume, the volume variable in response to a relative movement between the first and second suspension members, and a fluid flow circuit having a first end in fluidic communication with the fluid reservoir and a second end in fluidic communication with an isolated suspension location, the fluid flow circuit comprising a first valve, a second valve and a third valve, wherein said first and third valves are in parallel with each other and the second valve is in series with each of the first and third valves.

Claims

1. A suspension system comprising:

a first suspension member movable relative to a second suspension member;

a fluid reservoir having a volume, said volume variable in response to a relative movement between said first and second suspension members; and

a fluid flow circuit having a first end in fluidic communication with said fluid reservoir and a second end in fluidic communication with an isolated suspension location, said fluid flow circuit comprising a first valve, a second valve and a third valve, wherein said first and third valves are in parallel and said second valve is in series with each of said first and third valves, wherein said isolated suspension location comprises;

an inlet in fluidic communication with said second end of said fluid flow circuit;

an end barrier;

an annular enclosing wall defining an interior fluid pressure cavity between said inlet and said end barrier, said annular enclosing wall comprising;

an outer surface of a cylinder;

a flexible tubing;

a first compression region configured for sealingly compressing a first end of said flexible tubing against a first end of said outer surface of said cylinder; and

a second compression region comprising said inlet and configured for retainably compressing a second end of said flexible tubing against a second end of said outer surface of said cylinder.

2. The suspension system of claim 1, wherein said flexible tubing comprises extruded tube stock.

3. The suspension system claim 1, wherein said flexible tubing comprises pulltruded tube stock.

4. The suspension system of claim 1, wherein said first compression region comprises:

a portion of said first end of said flexible tubing; and

a first seal ring configured for said sealingly compressing said portion of said first end of said flexible tubing against said first end of said outer surface of said cylinder, such that said first end of said flexible tubing and said first end of said outer surface of said cylinder are sealingly squeezed shut.

5. The suspension system of claim 4, wherein said portion of said first end of said flexible tubing comprises an upset.

6. The suspension system of claim 1, wherein said second compression region comprises:

a portion of said second end of said flexible tubing; and

a seal ring configured for retainably compressing said portion of said second end of said flexible tubing against said second end of said outer surface of said cylinder, such that said second end of said flexible tubing and said second end of said outer surface of said cylinder are squeezed partially together to retain a first position while remaining open to a damping fluid flowing between said fluid flow circuit and said isolated suspension location.

7. The suspension system of claim 6, wherein said portion of said second end of said flexible tubing comprises an upset.

8. The suspension system of claim 1, wherein one of said first and second suspension members is an upper tube of a leg of a fork, and the other of said one of said first and second suspension members is a lower tube of said leg of said fork, and wherein said lower tube is configured for telescopically receiving said upper tube and is axially slidable relative thereto.

9. The suspension system of claim 1, further comprising:

a knob assembly selectively rotatable, said knob assembly comprising;

a damping valve adjustment knob configured for being rotated; and

a damping valve adjustment shaft configured for responding to rotational movement of said damping adjustment knob, said responding comprising moving axially in proportion to a thread helix and pushing or pulling on an adjustment shaft that is coupled with a needle valve, thereby adjusting an interference of said needle valve within a damping orifice that extends through a center of a damping piston, wherein during compression or extension of said suspension system said damping piston controls a flow of a damping fluid.

10. The suspension system of claim 1, wherein said second valve comprises:

a flow regulator configured for controlling a damping rate by providing resistance to damping fluid flowing there through, wherein a resistance provided by said flow regulator against a damping fluid is adjustable.

11. The suspension system of claim 10, wherein said damping rate is controlled during a flow of said damping fluid towards said isolated suspension location.

12. The suspension system of claim 10, wherein said damping rate is controlled during a rebound flow of said damping fluid away from said isolated suspension location.

13. The suspension system of claim 1, wherein said third valve is a boost valve configured for providing increasing resistance to compression as a piston rod progresses deeper into said fluid reservoir.

14. The suspension system of claim 13, wherein a volume exterior to said isolated suspension location is pressurized with gas above atmospheric pressure for increasing an ability of said boost valve to resist said compression.

15. A method for unlocking a suspension, said method comprising:

loading a suspension in compression;

opening at least one of a blow-off valve and a terrain sensitive damper valve;

flowing a damping fluid through at least one of said blow-off valve and said terrain sensitive damping valve; and

delivering said damping fluid, via a flow regulator, to a predetermined location of said suspension, said predetermined location being an isolated suspension location and being fluidly isolated from gas, wherein said isolated suspension location comprises;

an inlet in fluidic communication with a second end of a fluid flow circuit;

an end barrier;

an annular enclosing wall defining an interior fluid pressure cavity between said inlet and said end barrier, said annular enclosing wall comprising;

an outer surface of a cylinder;

a flexible tubing;

a first compression region configured for sealingly compressing a first end of said flexible tubing against a first end of said outer surface of said cylinder; and

a second compression region comprising said inlet and configured for retainably compressing a second end of said flexible tubing against a second end of said outer surface of said cylinder.

16. The method of claim 15, wherein said opening at least one of a blow-off valve and a terrain sensitive damper valve comprises:

opening said at least one of a blow-off valve and a damping valve when a predetermined threshold damping fluid pressure is exceeded.

17. The method of claim 16, further comprising:

adjusting said predetermined threshold damping fluid pressure imparted upon said at least one of a blow-off valve and said terrain sensitive damper valve via an pressure threshold adjustment knob.

18. The method of claim 15, further comprising:

delaying said damping valve from returning to a closed position for a predetermined period of time.

19. The method of claim 18, further comprising:

setting said predetermined period of time via a delay adjustment knob.

20. A damping suspension comprising:

a first tube;

a second tube telescopically receiving at least a portion of said first tube;

a cylinder having an inner and outer surface, said inner surface at least partially bounding a fluid reservoir;

a flexible tubing coupled with said cylinder, wherein a first end of said flexible tubing is sealingly compressed with a first end of said cylinder, and a second end of said flexible tubing is retainably compressed towards a second end of said cylinder; and

an isolated suspension location defined by an outer surface of said cylinder and an inner surface of said flexible tubing, said isolated suspension location having a fluid pressure cavity port that is in fluidic communication with a damping suspension valve assembly, wherein said flexible tubing is configured for expanding as damping fluid enters said isolated suspension location and is configured for compressing as said damping fluid leaves said isolated suspension location, wherein said damping suspension valve assembly is contained within a portion of said damping suspension at least partially in axial coincidence with said isolated suspension location.

21. The damping suspension of claim 20, further comprising:

a fluid flow circuit comprising a first end in fluidic communication with said fluid reservoir and a second end in fluidic communication with said isolated suspension location;

a first valve positioned along said fluid flow circuit, said first valve comprising a compression chamber there within and configured for opening and closing in response to a variable pressure imparted on said first valve by said damping fluid, wherein said compression chamber is in fluidic communication with both said isolated suspension location and said fluid reservoir when said first valve is open, and said compression chamber is in fluidic communication with said fluid reservoir when said first valve is closed;

a second valve comprising an upper surface coupled with said isolated suspension location and a lower surface coupled with said first valve via said fluid flow circuit, said second valve configured for providing resistance to said damping fluid flowing along said fluid flow circuit; and

a third valve coupled with said first valve, said third valve configured for pushing said damping fluid towards said isolated suspension location in response to a pressure imparted on said second valve during compression of said damping suspension that is equal to or greater than an operator-selectable threshold pressure when said first valve is in a substantially inhibiting movement position.

22. The damping suspension of claim 21, wherein said second valve is a flow regulator configured for controlling a damping rate by providing resistance to damping fluid flowing there through.

23. The damping suspension of claim 21, wherein said third valve is a blow-off valve.

24. A damping suspension valve assembly comprising:

a fluid flow circuit comprising a first end in fluidic communication with a fluid reservoir and a second end in fluidic communication with an isolated suspension location, said fluid reservoir receiving therein a variable volume, and said isolated suspension location receiving a damping fluid from said fluid flow circuit in response to said variable volume;

a first valve positioned along said fluid flow circuit, said first valve comprising a compression chamber there within and configured for opening and closing in response to a variable pressure imparted on said first valve by said damping fluid, wherein said compression chamber is in fluidic communication with both said isolated suspension location and said fluid reservoir when said first valve is open, and said compression chamber is in fluidic communication with said fluid reservoir when said first valve is closed;

a second valve comprising an upper surface coupled with said isolated suspension location and a lower surface coupled with said first valve via said fluid flow circuit, said second valve configured for providing resistance to said damping fluid flowing along said fluid flow circuit; and

a third valve in fluidic communication with said first and second valve, said third valve configured for pushing said damping fluid towards said isolated suspension location in response to a pressure imparted on said second valve during compression of said damping suspension that is equal to or greater than an operator-selectable threshold pressure when said first valve is in a substantially inhibiting movement position, wherein said isolated suspension location comprises;

an inlet in fluidic communication with said second end of said fluid flow circuit;

an end barrier;

an annular enclosing wall defining an interior fluid pressure cavity between said inlet and said end barrier, said annular enclosing wall comprising;

an outer surface of a cylinder;

a flexible tubing;

a first compression region configured for sealingly compressing a first end of said flexible tubing against a first end of said outer surface of said cylinder; and

a second compression region comprising said inlet and configured for retainably compressing a second end of said flexible tubing against a second end of said outer surface of said cylinder.

25. The damping suspension valve assembly of claim 24, wherein said second valve is a flow regulator, wherein a first portion of said fluid flow circuit moving there through is in series with a second portion of said fluid flow circuit moving through said first valve.

26. The damping suspension valve assembly of claim 24,

wherein said third valve is a blow-off valve.

27. A suspension damper comprising:

a compression chamber having a piston and rod movable therein;

a first flow path extending from a first compression chamber portion to a second compression chamber portion, wherein said first compression chamber portion and said second compression chamber portion is separated by said piston; and

a second flow path extending from said compression chamber to an isolated suspension location, said second flow path traversing at least one of a terrain sensitive valve and a bypass valve, said second flow path further traversing a flow regulator, wherein at least one of said flow regulator and said terrain sensitive valve and said bypass valve is axially overlapping at least a portion of said isolated suspension location, wherein said isolated suspension location comprises;

an inlet in fluidic communication with a second end of a fluid flow circuit;

an end barrier;

an annular enclosing wall defining an interior fluid pressure cavity between said inlet and said end barrier, said annular enclosing wall comprising;

an outer surface of a cylinder;

a flexible tubing;

a first compression region configured for sealingly compressing a first end of said flexible tubing against a first end of said outer surface of said cylinder; and

a second compression region comprising said inlet and configured for retainably compressing a second end of said flexible tubing against a second end of said outer surface of said cylinder.