# US 12,215,754 B2 · Shock absorber

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- Number: US 12,215,754 B2
- Document ID: US12215754B2
- Status: Granted
- Kind: B2
- Application number: 17/798,419
- Filed: 2021-02-09
- Published: 2023-03-09
- Granted: 2025-02-04
- Earliest claimed: 2020-02-14
- Assignees: Hitachi Astemo, Ltd.
- Applicants: Hitachi Astemo, Ltd.
- Inventors: Kosuke Kadokura
- Web page: https://patentgrep.com/patent/US12215754B2

## CPC

- F16F 9/465: {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)}
- F16F 9/348: 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)}
- F16F 9/185: {Bitubular units (where compression of gas leads to a clear spring action F16F9/062)}
- F16F: SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION

## Abstract

A pin portion in which an introduction orifice leading to a back-pressure chamber is formed is disposed along inner peripheries of a main body, a main valve, and a pilot casing. A nut disposed on the pin portion is rotated relative to the pin portion to fasten the main body, the main valve, and the pilot casing together. This eliminates the necessity of machining a tool engagement portion in the pin portion and represses an increase in man-hours.

## Claims

### Claim 1

A shock absorber comprising:
a cylinder in which a hydraulic fluid is sealed;
a piston inserted in the cylinder to define two chambers within the cylinder;
an outer tube disposed around an outer periphery of the cylinder;
a reservoir formed between the cylinder and the outer tube, the reservoir in which the hydraulic fluid and a gas are sealed;
a connecting pipe disposed between the cylinder and the outer tube and communicating into the cylinder; and
a damping force generation mechanism accommodated in a valve casing disposed on an outside of the outer tube, the damping force generation mechanism being connected to the connecting pipe,
the damping force generation mechanism including:
a main valve configured to generate a damping force;
a seat member which the main valve abuts;
a pilot casing that forms a back-pressure chamber formed on a back side of the main valve and having inner pressure that acts on the main valve in a valve-closing direction;
a pilot valve configured to adjust the inner pressure of the back-pressure chamber; and
a pin member that is disposed along inner peripheries of the seat member, the main valve, and the pilot casing, the pin member in which an introduction orifice leading to the back-pressure chamber is formed,
the pin member being provided with a fastening member that is rotated relative to the pin member to fasten the seat member, the main valve, and the pilot casing together,
the fastening member being disposed in an axial clearance between the pilot casing and the pilot valve.

### Claim 2 (depends on 1)

The shock absorber according to claim 1,
wherein a plurality of chamfered portions is formed in an outer peripheral side of the pilot casing.

### Claim 3 (depends on 1)

The shock absorber according to claim 1,
wherein the pin member is formed integrally with the seat member.

### Claim 4 (depends on 1)

The shock absorber according to claim 1,
wherein the pilot casing is provided with a check valve that allows a hydraulic fluid to flow toward the back-pressure chamber according to pressure on a downstream side of the introduction path and on an upstream side of the pilot valve.

### Claim 5

A solenoid valve comprising:
a main valve configured to generate a damping force;
a seat member which the main valve abuts;
a pilot casing that forms a back-pressure chamber formed on a back side of the main valve and having inner pressure that acts on the main valve in a valve-closing direction;
a pilot valve configured to adjust the inner pressure of the back-pressure chamber using the solenoid valve; and
a pin member that is disposed along inner peripheries of the seat member, the main valve, and the pilot casing, the pin member in which an introduction orifice leading to the back-pressure chamber is formed,
the pin member being provided with a fastening member that is rotated relative to the pin member to fasten the seat member, the main valve, and the pilot casing together, the fastening member being disposed between an axial clearance between the pilot casing and the pilot valve.