Shock absorber with hydraulic compression stop valve

Patent metadata

Field	Value
Publication number	US-10746252-B2
Application number	US-201816120184-A
Country	US
Kind code	B2
Filing date	Aug 31, 2018
Priority date	Nov 27, 2017
Publication date	Aug 18, 2020
Grant date	Aug 18, 2020

Abstract

A shock absorber having a main tube extends between a first end and a second end defining a fluid chamber therebetween. A main piston is slidably disposed in the fluid chamber dividing the fluid chamber into a compression chamber and a rebound chamber. A piston rod is attached to the main piston. A hydraulic compression stop including an additional piston is attached to the piston rod for movement therewith. The additional piston includes a body extending from the piston rod and defining a conduit extending along the center axis. An actuator is disposed in the conduit and attached to the body movable from a closed position to an open position during the compression stroke with the open position allowing fluid flow through the actuator and the conduit and the closed position preventing fluid flow through the actuator. The actuator includes a spring and a blocking member disposed in the conduit.

First claim

What is claimed is:

1. A shock absorber assembly comprising:
a main tube disposed on a center axis and extending between a first end and a second end defining a fluid chamber extending therebetween for containing a working fluid;
a main piston slidably disposed in said fluid chamber dividing said fluid chamber into a compression chamber between said main piston and said first end and a rebound chamber being between said main piston and said second end;
a piston rod disposed on said center axis and attached to said main piston for moving said main piston in a compression stroke and a rebound stroke;
a hydraulic compression stop including an additional piston disposed in said compression chamber adjacent to said main piston and attached to said piston rod for movement with said piston rod during said compression stroke and said rebound stroke to provide additional damping force;
said additional piston including a body disposed on said center axis extending from said piston rod to a body end spaced from said first end and defining a conduit extending along said center axis and in fluid communication with said fluid chamber; and
an actuator disposed in said conduit and attached to said body and being movable from a closed position to an open position during said compression stroke with said open position allowing the working fluid to flow through said actuator and said conduit and said closed position preventing the working fluid from flowing through said actuator and said conduit;
wherein said conduit has a cylindrical shape defining a conduit diameter for receiving said actuator;
wherein a retainer is disposed in said conduit and is attached to said body for securing said actuator in said conduit;

wherein said retainer defines a hole having a hole diameter being less than said conduit diameter and disposed on said center axis and in fluid communication with said conduit for allowing the working fluid to flow through said retainer and said conduit;
wherein said actuator includes a first spring having a predetermined spring tension disposed in said conduit and a blocking member disposed in said conduit and sandwiched between said first spring and said retainer for limiting the flow of the working fluid through said conduit;
wherein said blocking member is a disc of circular shape disposed between said first spring and said retainer;
wherein a second spring having a predetermined spring tension is disposed in said conduit and extends between said retainer and said disc to sandwich said disc between said first spring and said second spring and spaces said disc from said retainer.

2. The shock absorber as set forth in claim 1 wherein said body defines at least one orifice disposed in fluid communication with said conduit for allowing the working fluid to exit said body.

3. The shock absorber assembly as set forth in claim 2 wherein said at least one orifice includes a pair of orifices having a first orifice defining a first orifice diameter and a second orifice defining a second orifice diameter disposed opposite of one another relative to said center axis.

4. The shock absorber assembly as set forth in claim 3 wherein said first orifice diameter is greater than said second orifice diameter.

5. The shock absorber assembly as set forth in claim 1 wherein said disc defines a disc diameter being greater than said hole diameter for biasing against said retainer to prevent the working fluid from flowing through said conduit and greater than said conduit diameter to allow the working fluid to flow around said disc and through said conduit in response to a fluid pressure being greater than said predetermined spring tension of said second spring.

6. The shock absorber assembly as set forth in claim 1 wherein said disc defines an opening defining an opening diameter disposed on said center axis for allowing fluid communication through said disc.

7. The shock absorber assembly as set forth in claim 6 further including a shaft disposed in said conduit between said disc and said first spring and extending along said center axis through said opening for limiting fluid flow through said opening of said disc.

8. The shock absorber assembly as set forth in claim 7 wherein said shaft includes a collar disposed in said conduit and extending radially outwardly from said shaft and annularly about said center axis defining a collar diameter with said collar diameter being greater than said opening diameter to prevent said shaft from sliding through said opening and block fluid flow through said opening.

Assignees

• Beijingwest Ind Co Ltd

Inventors

• Flacht Piotr Andrzej
• Kasprzyk Dominik

Classifications

• F16F9/3405

  Throttling passages in or on piston body, e.g. slots (F16F9/344, F16F9/3481 take precedence) · CPC title

• F16F9/3221

  of piston rods · CPC title

• F16F2228/066

  Variable stiffness · CPC title

• F16F9/348

  Throttling passages in the form of annular discs {or other plate-like elements which may or may not have a spring action}, operating in opposite directions {or singly, e.g. annular discs positioned on top of the valve or piston body (F16F9/341, F16F9/3415 take precedence)} · 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