Shock absorber

Patent metadata

Field	Value
Publication number	US-2016229255-A1
Application number	US-201415022921-A
Country	US
Kind code	A1
Filing date	Sep 19, 2014
Priority date	Sep 20, 2013
Publication date	Aug 11, 2016
Grant date	—

Abstract

A shock absorber includes at least one of an expansion-side sensitive unit and a contraction-side sensitive unit. The expansion-side sensitive unit has an expansion-side actuating chamber that communicates with an expansion-side chamber and a contraction-side chamber, an expansion-side free piston that partitions the expansion-side actuating chamber into a first expansion-side pressure chamber and a second expansion-side pressure chamber, and an expansion-side spring element configured to bias the expansion-side free piston to compress the first expansion-side pressure chamber. The contraction-side sensitive unit has a contraction-side actuating chamber that communicates with a contraction-side chamber and a reservoir, a contraction-side free piston that partitions the contraction-side actuating chamber into a first contraction-side pressure chamber and a second contraction-side pressure chamber, and a contraction-side spring element configured to bias the contraction-side free piston to compress the first contraction-side pressure chamber.

First claim

1 . A shock absorber comprising:
a cylinder; a piston slidably inserted into the cylinder, the piston partitioning the cylinder into an expansion-side chamber and a contraction-side chamber; a piston rod movably inserted into the cylinder, the piston rod being connected to the piston; a reservoir that stores a hydraulic fluid; a charge passage configured to allow only a flow of hydraulic fluid directed from the reservoir to the contraction-side chamber; a rectification passage configured to allow only a flow of hydraulic fluid directed from the contraction-side chamber to the expansion-side chamber; a damping force adjuster configured to allow only a flow of hydraulic fluid directed from the expansion-side chamber to the reservoir and change resistance to the flow of hydraulic fluid; and at least one of an expansion-side sensitive unit operated in an expanding motion of the shock absorber and a contraction-side sensitive unit operated in a contracting motion of the shock absorber, wherein the expansion-side sensitive unit has
an expansion-side actuating chamber that communicates with the expansion-side chamber and the contraction-side chamber,
an expansion-side free piston slidably inserted into the expansion-side actuating chamber, the expansion-side free piston partitioning the expansion-side actuating chamber into a first expansion-side pressure chamber communicating with the expansion-side chamber and a second expansion-side pressure chamber communicating with the contraction-side chamber, and
an expansion-side spring element configured to bias the expansion-side free piston to compress the first expansion-side pressure chamber, and
the contraction-side sensitive unit has
a contraction-side actuating chamber that communicates with the contraction-side chamber and the reservoir,
a contraction-side free piston slidably inserted into the contraction-side actuating chamber, the contraction-side free piston partitioning the contraction-side actuating chamber into a first contraction-side pressure chamber communicating with the contraction-side chamber and a second contraction-side pressure chamber communicating with the reservoir, and
a contraction-side spring element configured to bias the contraction-side free piston to compress the first contraction-side pressure chamber.

2 . The shock absorber according to claim 1 , further comprising:
a first expansion-side passage that connects the first expansion-side pressure chamber and the expansion-side chamber; a second expansion-side passage that connects the second expansion-side pressure chamber and the contraction-side chamber; and an expansion-side valve element provided in at least one of the first expansion-side passage and the second expansion-side passage, the expansion-side valve element being configured to generate resistance to a flow of hydraulic fluid passing therethrough.

3 . The shock absorber according to claim 2 , wherein the expansion-side valve element is an expansion-side valve configured to allow only a flow of hydraulic fluid directed from the expansion-side chamber to the contraction-side chamber and generate resistance to the flow of hydraulic fluid.

4 . The shock absorber according to claim 2 , further comprising a check valve arranged in parallel with the expansion-side valve element, the check valve being configured to allow only a flow of hydraulic fluid directed from the contraction-side chamber to the expansion-side chamber.

5 . The shock absorber according to claim 1 , further comprising:
a first contraction-side passage that connects the first contraction-side pressure chamber and the contraction-side chamber; a second contraction-side passage that connects the second contraction-side pressure chamber and the reservoir; and a contraction-side valve element provided in at least one of the first contraction-side passage and the second contraction-side passage, the contraction-side valve element being configured to generate resistance to a flow of hydraulic fluid passing therethrough.

6 . The shock absorber according to claim 5 , wherein the contraction-side valve element is a contraction-side valve configured to allow only a flow of hydraulic fluid directed from the contraction-side chamber to the reservoir and generate resistance to the flow of hydraulic fluid.

7 . The shock absorber according to claim 5 , further comprising a check valve arranged in parallel with the contraction-side valve element, the check valve being configured to allow only a flow of hydraulic fluid directed from the reservoir to the contraction-side chamber.

8 . The shock absorber according to claim 1 , further comprising:
an expansion-side housing that forms the expansion-side actuating chamber; and an expansion-side cushioning portion configured to prevent collision between the expansion-side housing and the expansion-side free piston.

9 . The shock absorber according to claim 1 , further comprising:
a contraction-side housing that forms the contraction-side actuating chamber; and a contraction-side cushioning portion configured to prevent collision between the contraction-side housing and the contraction-side free piston.

10 . The shock absorber according to claim 1 , further comprising:
an expansion-side housing that forms the expansion-side actuating chamber; and an expansion-side liquid pressure cushioning portion configured to prevent collision between the expansion-side housing and the expansion-side free piston.

11 . The shock absorber according to claim 1 , further comprising:
a contraction-side housing that forms the contraction-side actuating chamber; and a contraction-side liquid pressure cushioning portion configured to prevent collision between the contraction-side housing and the contraction-side free piston.

12 . The shock absorber according to claim 1 , further comprising:
an expansion-side housing that forms the expansion-side actuating chamber; and an expansion-side cushioning spring element configured to bias the expansion-side free piston against the expansion-side spring element to compress the second expansion-side pressure chamber and prevent collision between the expansion-side housing and the expansion-side free piston.

13 . The shock absorber according to claim 1 , further comprising:
a contraction-side housing that forms the contraction-side actuating chamber; and a contraction-side cushioning spring element configured to bias the contraction-side free piston against the contraction-side spring element to compress the second contraction-side pressure chamber and prevent collision between the contraction-side housing and the contraction-side free piston.

14 . The shock absorber according to claim 1 , further comprising an expansion-side housing that forms the expansion-side actuating chamber, the expansion-side housing being configured to act as a piston nut for connecting the piston to the piston rod.

15 . The shock absorber according to claim 1 , further comprising:
a contraction-side housing that forms the contraction-side actuating chamber; a valve casing fitted to an end of the cylinder, the valve casing having an inlet port connecting the reservoir and the contraction-side chamber; and a check valve stacked on the valve casing, the check valve being configured to open or close the inlet port, wherein the charge passage includes the inlet port and the check valve, and the check valve is fixed to the valve casing by connecting the contraction-side housing to the valve casing.

Assignees

• Kyb Corp

Inventors

• Teraoka Takashi
• Masamura Tatsuya

Classifications

• B60G15/061

  with a coil spring being mounted inside the damper · CPC title

• F16F9/50

  Special means providing automatic damping adjustment, {i.e. self-adjustment of damping by particular sliding movements of a valve element, other than flexions or displacement of valve discs}(F16F9/53 takes precedence); {Special means providing self-adjustment of spring characteristics} · 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

• B60G17/08 Primary

  Characteristics of fluid dampers (adjusting fluid dampers in general F16F9/44 - F16F9/53) · CPC title

• F16F9/46

  allowing control from a distance {, i.e. location of means for control input being remote from site of valves, e.g. on damper external wall (attachment of valve units to cylinders F16F9/325)} · CPC title