Hydraulic compression stop with necked-down cylinder tube

Patent metadata

Field	Value
Publication number	US-2025067317-A1
Application number	US-202418766662-A
Country	US
Kind code	A1
Filing date	Jul 9, 2024
Priority date	Aug 25, 2023
Publication date	Feb 27, 2025
Grant date	—

Abstract

A damper assembly includes a main tube filled with a working liquid; a piston assembly connected to a rod and slidably disposed within the main tube. The piston assembly divides an interior of the main tube into a rebound chamber and a compression chamber. A hydraulic compression stop (HCS) assembly includes a piston sleeve disposed in the compression chamber and attached to the piston assembly. The main tube includes a shoulder and a necked-down portion extending from the shoulder and having a reduced diameter smaller than a diameter of the main tube opposite of the shoulder. The necked-down portion is configured to receive the piston sleeve. A tubular wall is disposed around the necked-down portion and defines an external flow channel outside of the main tube. The necked-down portion defines a plurality of axially-spaced holes each providing fluid communication between the compression chamber and the external flow channel.

First claim

What is claimed is:

1 . A damper assembly comprising:
a main tube filled with a working liquid; a rod disposed at least partially within the main tube; a piston assembly connected to the rod and slidably disposed within the main tube, the piston assembly dividing an interior of the main tube into a rebound chamber and a compression chamber; a hydraulic compression stop assembly including a piston sleeve disposed in the compression chamber and attached to the piston assembly; the main tube including a shoulder and a necked-down portion extending from the shoulder and having a reduced diameter smaller than a diameter of the main tube opposite of the shoulder, wherein the necked-down portion is configured to receive the piston sleeve; and a tubular wall disposed around the necked-down portion and defining an external flow channel outside of the main tube; and wherein the necked-down portion defines a plurality of axially-spaced holes, each providing fluid communication between the compression chamber and the external flow channel.

2 . The damper assembly of claim 1 , further comprising a base valve assembly located at a closed end of the main tube and configured to control a flow of the working liquid between the compression chamber and a compensation chamber.

3 . The damper assembly of claim 2 , wherein the base valve assembly includes a compression valve assembly and a rebound valve assembly each configured to control the flow of the working liquid between the compression chamber and the compensation chamber.

4 . The damper assembly of claim 2 , further comprising an outer tube disposed annularly about the main tube and defining the compensation chamber therebetween.

5 . The damper assembly of claim 2 , further comprising a rebound check valve configured to allow fluid flow from the base valve assembly and into the compression chamber while blocking fluid flow in an opposite direction, thereby bypassing the external flow channel during a rebound stroke.

6 . The damper assembly of claim 1 , further including a spring disposed between and attached to each of the piston sleeve and the piston assembly, thereby allowing the piston sleeve to move in an axial direction and relative to the piston assembly.

7 . The damper assembly of claim 6 , wherein the piston sleeve includes a tubular portion defining a spring retainer configured to hold an end of the spring opposite from the piston assembly.

8 . The damper assembly of claim 6 , wherein the spring includes a coil spring.

9 . The damper assembly of claim 6 , wherein the spring is at least partially disposed within the piston sleeve.

10 . The damper assembly of claim 6 , wherein the spring is integrally formed with the piston sleeve.

11 . The damper assembly of claim 6 , wherein the spring and the piston sleeve are formed of a plastic material.

12 . The damper assembly of claim 1 , wherein the plurality of axially-spaced holes includes a second plurality of holes circumferentially spaced apart from one another.

13 . The damper assembly of claim 1 , further comprising a compression safety valve configured to open at a predefined threshold of pressure within the compression chamber and to allow the working liquid to flow out of the compression chamber and to bypass the plurality of axially-spaced holes and the external flow channel.

14 . The damper assembly of claim 2 , further comprising an adapter fixed to the base valve assembly and configured to regulate fluid flow between the compression chamber and the base valve assembly.

15 . The damper assembly of claim 14 , wherein the adapter defines a plurality of flow passages providing fluid communication between the external flow channel and the base valve assembly.

16 . The damper assembly of claim 14 , wherein the adapter encloses a bottom end of the main tube adjacent to the base valve assembly; and
wherein the adapter includes a rebound check valve configured to allow fluid flow from the base valve assembly and into the compression chamber while blocking fluid flow in an opposite direction, thereby bypassing the external flow channel during a rebound stroke.

17 . The damper assembly of claim 1 , wherein the piston assembly further includes at least one valve assembly configured to regulate a flow of the working liquid between the rebound chamber and the compression chamber and to thereby generate a damping force.

18 . A hydraulic compression stop assembly for a damper, comprising:
a piston sleeve having a tubular shape attached to a piston; a main tube defining a compression chamber and including a shoulder and a necked-down portion extending from the shoulder and having a reduced diameter smaller than a diameter of the main tube opposite of the shoulder, wherein the necked-down portion is configured to receive the piston sleeve; and a tubular wall disposed around the necked-down portion and defining an external flow channel outside of the main tube; and wherein the necked-down portion defines a plurality of axially-spaced holes each providing fluid communication between an interior of the necked-down portion and the external flow channel.

19 . The hydraulic compression stop assembly of claim 18 , further comprising an adapter at least partially enclosing an end of the necked-down portion and configured to regulate fluid flow therethrough.

20 . The hydraulic compression stop assembly of claim 19 , wherein the adapter includes a rebound check valve configured to allow fluid flow into the compression chamber while blocking fluid flow in an opposite direction, thereby bypassing the external flow channel during a rebound stroke.

Assignees

• Beijingwest Ind Co Ltd

Inventors

• Popielarz Michal Jerzy
• Kasprzyk Dominik

Classifications

• F16F9/346

  Throttling passages in the form of slots arranged in cylinder walls · CPC title

• F16F9/483

  characterised by giving a particular shape to the cylinder, e.g. conical · CPC title

• F16F9/3257 Primary

  in twin-tube type devices · CPC title

• F16F9/49 Primary

  Stops limiting fluid passage, e.g. hydraulic stops {or elastomeric elements inside the cylinder which contribute to changes in fluid damping (fluid-actuated displacement devices with means for accelerating or decelerating the stroke F15B15/22)} · CPC title

• F16F9/34

  Special valve constructions ({F16F9/44, F16F9/50 take precedence; filtering details F16F9/3285} ; valves in general F16K); Shape or construction of throttling passages · CPC title