Twin tube damper including a pressure rate sensitive system

Patent metadata

Field	Value
Publication number	US-10648527-B2
Application number	US-201815940824-A
Country	US
Kind code	B2
Filing date	Mar 29, 2018
Priority date	Apr 24, 2017
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

A twin tube damper assembly includes a main tube defining a fluid chamber. An external tube extends about the main tube defining a compensation chamber therebetween. A piston, slidably disposed in the fluid chamber, divides the fluid chamber into a compression chamber and a rebound chamber. A rod guide is disposed in the rebound chamber, attached to the main tube and the external tube, defining at least one channel in fluid communication with the rebound and compensation chambers. A piston rod extends through the rod guide and is attached to the piston. A pressure rate sensitive system, disposed in the rebound chamber, is attached to the rod guide in fluid communication with the at least one channel, the rebound chamber, and the compensation chamber for regulating the working fluid flow through the rod guide between the rebound and compensation chambers during compression and rebound strokes.

First claim

What is claimed is:

1. A twin tube damper assembly comprising:
a main tube disposed on a center axis and extending between a first end and a second end and defining a fluid chamber extending therebetween for containing a working fluid;
an external tube disposed on said center axis spaced from said main tube and extending about said main tube between a closed end adjacent to said first end and an opened end adjacent to said second end and defining compensation chamber between said main tube and said external tube;
a piston slidably disposed in said fluid chamber dividing said fluid chamber into a compression chamber between said first end and said piston and a rebound chamber between said piston and said second end;
a rod guide disposed in said rebound chamber and attached to said second end of said main tube and said opened end of said external tube and defining at least one channel disposed in fluid communication between said rebound chamber and said compensation chamber to allow the working fluid to flow between said fluid chamber and said compensation chamber;
a piston rod extending along said center axis through said rod guide and attached to said piston for moving said piston between a compression stroke and a rebound stroke;
a pressure rate sensitive system disposed in said rebound chamber and attached to said rod guide and in fluid communication with said at least one channel of said rod guide and said rebound chamber and said compensation chamber for regulating flow of the working fluid through said rod guide between said rebound chamber and said compensation chamber during said compression stroke and said rebound stroke to provide additional damping;
wherein said pressure rate sensitive system includes a wall disposed in said rebound chamber spaced from said main tube and secured to said rod guide and extending to a wall end to define a compartment between said rod guide and said wall end;
wherein said pressure rate sensitive system includes a relief valve disposed in said compartment abutting said at least one channel to regulate the working fluid flow from said fluid chamber to said compensation chamber whereby said relief valve is movable between an active mode with said relief valve being spaced from said at least one channel to open fluid communication between said fluid chamber and said at least one channel and said compensation chamber and a non-active mode with said relief valve being in an abutment relationship with said at least one channel to close fluid communication between said fluid chamber and said compensation chamber; and
a partitioning member slidably disposed in said compartment about said piston rod and spaced from said relief valve dividing said compartment into a first portion between said rod guide and said partitioning member and a second portion between said partitioning member and said wall end.

2. The twin tube damper assembly as set forth in claim 1 wherein said relief valve has a circular shape and a frusto-conical shaped cross-section.

3. The twin tube damper assembly as set forth in claim 1 wherein said wall includes a flange extending radially inwardly from said wall end to said piston rod.

4. The twin tube damper assembly as set forth in claim 3 wherein said flange defines at least one inlet spaced radially from said piston rod for allowing the working fluid to flow into said second portion of said compartment and at least one outlet spaced radially from said inlet for allowing the working fluid to exit said second portion of said compartment.

5. The twin tube damper assembly as set forth in claim 4 further including an elastic member disposed in said second portion of said compartment extending between said relief valve and said partitioning member to bias said relief valve against said at least one channel of said rod guide in said non-active mode and said partitioning member against said flange in a blocked position to prevent the working fluid from flowing into said second portion of said compartment.

6. The twin tube damper assembly as set forth in claim 5 wherein said elastic member is a spring extending annularly and helically about said piston rod between said relief valve and said partitioning member.

7. The twin tube damper assembly as set forth in claim 4 further including a restrictor valve disposed in said rebound chamber and attached to said flange and covering said outlet to limit the fluid flow from said second portion of said compartment to said rebound chamber to provide additional damping force.

8. The twin tube damper assembly as set forth in claim 7 further including a retainer disposed in said rebound chamber adjacent to said flange and said restrictor valve and attached to said pressure rate sensitive system to secure said restrictor valve to the pressure rate sensitive system.

9. The twin tube damper assembly as set forth in claim 3 wherein said partitioning member defines a groove extending about said partitioning member; and
a seal disposed in said groove and extending annularly about said partitioning member and in an abutment relationship with said wall to isolate said first portion of said compartment with said second portion of said compartment.

10. The twin tube damper assembly as set forth in claim 3 wherein said partitioning member defines at least one orifice extending through said partitioning member to allow the working fluid to flow from said first portion of said compartment and said second portion of said compartment, and
a restrictor valve disposed in said first portion adjacent to said partitioning member to cover said at least one orifice.

11. The twin tube damper assembly as set forth in claim 5 wherein said rod guide includes a body disposed on said center axis in said rebound chamber and attached to said second end of said main tube to close said rebound chamber.

12. The twin tube damper assembly as set forth in claim 11 wherein said body including an extension portion disposed in said rebound chamber spaced from said main tube and extending outwardly from said body along said center axis to a terminal end.

13. The twin tube damper assembly as set forth in claim 12 wherein said rod guide further includes a projection extending radially outwardly from said body and annularly about said center axis to said opened end of said external tube to close said compensation chamber.

14. The twin tube damper assembly as set forth in claim 13 wherein said rod guide defines a bore disposed on said center axis and extending along said center axis through said body and said extension portion for receiving said piston rod; and
a cavity disposed on said center axis at said terminal end and in fluid communication with said bore and said first portion of said compartment.

15. The twin tube damper assembly as set forth in claim 14 wherein said at least one channel includes a first channel disposed adjacent to said body spaced from said cavity and in fluid communication with said rebound chamber and said first portion of said compartment and extending through said extension portion perpendicular to said center axis for allowing the working fluid to flow from said rebound chamber into said first portion of said compartment.

16. The twin tube damper assembly as set forth in claim 15 wherein said extension portion of said rod guide defines a second channel spaced from said first channel and in fluid communication with said first portion of said compartment and said compensation chamber for allowing the working fluid to flow from said rebound chamber through said rod guide to said compensation chamber.

Assignees

• Beijingwest Ind Co Ltd

Inventors

• Slusarczyk Pawel
• Wrzesinski Jakub

Classifications

• F16F9/465

  using servo control, the servo pressure being created by the flow of damping fluid, e.g. controlling pressure in a chamber downstream of a pilot passage (self-adjustment of damping F16F9/50) · CPC title

• F16F9/5126

  Piston, or piston-like valve elements (F16F9/504 takes precedence) · CPC title

• F16F9/3257 Primary

  in twin-tube type devices · CPC title

• B60G17/06

  Characteristics of dampers {, e.g. mechanical dampers}(B60G17/015 takes precedence) · CPC title

• B60G13/08

  hydraulic · CPC title