Twin tube damper with remote gas reservoir

Patent metadata

Field	Value
Publication number	US-11400783-B2
Application number	US-202016791420-A
Country	US
Kind code	B2
Filing date	Feb 14, 2020
Priority date	Apr 11, 2014
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

A damper is provided having a twin tube construction interconnected to a gas reservoir. The connection of each of the inner and outer volumes of the twin tube to the gas reservoir is independently valved, and each of these valves are independently settable to change the differential pressure thereacross at which they open. The damper provides flow passages directly from the inner and outer volumes to enable flow form the compression to rebound sides thereof, as well as through the valved connections to the gas reservoir and at least one valved opening in the damper piston.

First claim

I claim:

1. A fluid damper comprising:
an inner tube forming an inner fluid volume;
an outer tube forming an outer fluid volume;
at least one flow passage extending through said inner tube to enable fluid communication between said inner fluid volume and said outer fluid volume, wherein at least one opening of said flow passage is not formed in a side wall of said inner tube;

a remote reservoir in fluid communication with said inner fluid volume and said outer fluid volume, said remote reservoir comprising:
a fluid portion;
a gas portion; and
a floating piston separating said fluid portion and said gas portion;

a valved interconnection fluidically coupling said remote reservoir with said inner fluid volume and said outer fluid volume, said valved interconnection comprising:
a first flow passage extending between said inner fluid volume and said fluid portion of said remote reservoir;
a second flow passage extending between said outer fluid volume and said fluid portion of said remote reservoir; and
at least one valve interposed in at least one of said first flow passage and said second flow passage, wherein said at least one valve controls fluid flow through said at least one of said first flow passage and said second flow passage; and

a damping piston moveable within said inner tube and connected to a shaft extending outwardly of said inner tube through a sealed end thereof, movement of said damping piston enabling fluid to flow between one side of said damping piston and said fluid portion of said remote reservoir via said valved interconnection and at least one of said inner fluid volume and said outer fluid volume, said damping piston sealingly isolates said inner tube into a compression volume and a rebound volume.

2. The fluid damper of claim 1 , wherein said damping piston sealingly isolates said inner tube into a compression volume and a rebound volume, wherein said rebound volume is in continuous fluid communication with said outer fluid volume of said outer tube.

3. The fluid damper of claim 2 , wherein said outer fluid volume is an annular volume extending around said inner fluid volume.

4. The fluid damper of claim 3 , wherein reaching a threshold of a difference in fluid pressure across said at least one valve in said first flow passage and said second flow passage, thereby achieving a threshold difference in fluid pressure, causes an opening of said at least one valve to open to fluid flow therethrough.

5. The fluid damper of claim 4 , wherein a level of said threshold difference in fluid pressure of said at least one valve is adjustable.

6. The fluid damper of claim 4 , wherein a level of said threshold difference in fluid pressure of said at least one valve in said first flow passage is independently adjustable with respect to a level of said threshold difference in fluid pressure of said at least one valve in said second flow passage.

7. The fluid damper of claim 5 , wherein a valve of said at least one valve comprises:
a through hole extending therethrough, and a bendable shim extending across said opening, wherein a bending of said bendable shim away from said opening enables opening of said fluid passage to flow therethrough; and
a spring plate biased by a spring to selectively press against said shim to urge said shim in a direction to close said opening of said valve of said at least one valve.

8. The fluid damper of claim 7 , wherein said inner tube comprises:
a plurality of openings spaced in a direction of travel of said piston therein and extending between said inner fluid volume and said outer fluid volume, said plurality of openings being in an annular wall of said inner tube, and said movement of said position of said piston therein exposes different ones of said openings to said fluid volume of said inner tube on either side of said piston.

9. The fluid damper of claim 8 , wherein at least a first opening and a second opening of said plurality of openings in said inner tube are spaced part, in a direction of said piston travel, by a gap greater than a width in said piston.

10. The fluid damper of claim 9 , wherein said piston is disposed intermediate of said first opening and said second opening, such that, during a stroke of said piston in said direction of said first opening, a first portion of fluid flows from a first side of said piston, through said first opening in said annular wall, and a second portion of fluid simultaneously flows through said second of said openings and into a volume at said second side of said piston.

11. The fluid damper of claim 10 , wherein said first opening and said second opening are in fluid communication through an annular volume extending around an inner volume.

12. A fluid damper, comprising:
a first fluid volume partially bounded by a sealed opening through which a piston shaft extends inwardly and outwardly of said first fluid volume, said piston shaft having a piston coupled thereto, said piston located within said first fluid volume, said piston disposed to separate said first fluid volume into a compression side and a rebound side;
a first fluid pathway between said first fluid volume and an outer fluid volume wherein at least one opening of said fluid pathway is not formed in a side wall of an inner tube;
a reservoir comprising:
a gas portion; and
a fluid portion separated from said gas portion; and

a valved interconnection housing, wherein said valved interconnection housing includes a first valved flow passage extending between said compression side of said first fluid volume and said fluid portion of said reservoir.

13. The fluid damper of claim 12 wherein said valved interconnection housing further comprises
a second valved flow passage extending between said rebound side of said first fluid volume and said fluid portion of said reservoir.

14. The fluid damper of claim 13 , wherein at least one valve of said first valved flow passage and said second valved flow passage are adjustable to select a pressure at which they open.

15. The fluid damper of claim 14 , wherein said at least one valve of said first valved flow passage and said second valved flow passage are independently adjustable, with respect to each other, to select said pressure at which they open.

16. A fluid damper, comprising:
an inner tube and an outer tube, said outer tube at least partially surrounding said inner tube, said inner tube and said outer tube at least partially defining an inner fluid volume and an outer fluid volume;
a damping piston moveably disposed within said fluid damper, said damping piston coupled to a piston shaft, said piston shaft moveable into said inner tube and also moveable out of said inner tube via a sealed opening;
a first fluid pathway between said inner fluid volume and said outer fluid volume wherein at least one opening of said fluid pathway is not formed in a side wall of said inner tube;
a reservoir, said reservoir further comprising:
a pressurizable gas volume;
a fluid volume; and
a floating piston, said floating piston disposed between said pressurizable gas volume and said fluid volume;

a first valved passage extending between said inner fluid volume and said fluid volume of said gas reservoir;
a second valved passage extending between said outer fluid volume and said fluid volume of said gas reservoir; and
a valve disposed in at least one of said first valved passage and said second valved passage, operation of said valve at least partially based upon a threshold value of a difference in pressure across said valve.

17. The fluid damper of claim 16 , w

Assignees

• Fox Factory Inc

Inventors

• Cox Christopher Paul

Classifications

• B60G2300/12

  Cycles; Motorcycles · CPC title

• B60G13/06 Primary

  of fluid type · CPC title

• F16F9/065

  Expansion chamber provided on the upper or lower end of a damper, separately there from or laterally on the damper · CPC title

• B60G2500/10

  Damping action or damper · CPC title

• B62K25/04

  for mounting axles resiliently on cycle frame or fork (for sidecars, forecars or the like B62K27/06) · CPC title