公开(公告)号：US20240191768A1

公开(公告)日：2024-06-13

申请号：US18282051

申请日：2022-03-04

Applicant: Hitachi Astemo, Ltd.

Inventor： Hirohito ISHII ,  Osamu YUNO

IPC: F16F9/18 ,  F16F9/34 ,  F16F9/512

CPC classification number: F16F9/18 ,  F16F9/34 ,  F16F9/5126

Abstract: The invention is directed to provide a shock absorber in which hydraulic fluid is restrained from leaking out from a gap between a sub-check valve provided at a passage opening of an orifice passage and a disc valve. The sub-check valve (133) is biased toward the opening (126) of the orifice passage (130) using a biasing disc (135) (biasing member) of substantially equal diameter to the sub-check valve (133). This makes it possible to restrain hydraulic fluid in a first chamber (2A) from leaking out from a gap between a disc valve (121) and the sub-check valve (133) into a second chamber (2B) when piston velocity during an extension stroke is low (0.1 m/s or lower, exclusive zero), and thus obtain an intended damping force.

公开(公告)号：US20240093752A1

公开(公告)日：2024-03-21

申请号：US18274637

申请日：2022-03-04

Applicant: Hitachi Astemo, Ltd.

Inventor： Chihiro YABE ,  Osamu YUNO ,  Takao NAKADATE

IPC: F16F9/348

CPC classification number: F16F9/348

Abstract: One aspect of the present invention is configured in such a manner that a main valve (a valve member) is in abutment with only a ridge portion (a second protrusion portion) on the inner peripheral side of a seat portion (a first seat portion) in a state of being mounted on a piston. This configuration can reduce the radial contact width between the main valve and the seat portion, and contribute to preventing or reducing variations in the valve-opening point and the damping force by managing the radial dimension of the ridge portion on the inner peripheral side of the seat portion to allow the contact diameter between the main valve and the seat portion to be kept constant.

公开(公告)号：US20240077126A1

公开(公告)日：2024-03-07

申请号：US18273586

申请日：2022-02-01

Applicant: Hitachi Astemo, Ltd.

Inventor： Takahiro MORI ,  Osamu YUNO ,  Takao NAKADATE

IPC: F16F9/348 ,  F16F9/19 ,  F16F9/48

CPC classification number: F16F9/348 ,  F16F9/19 ,  F16F9/48

Abstract: The present invention causes a low-rigidity disk to be supported by a backup disk (a deformation prevention portion), and therefore can prevent the low-rigidity disk from being deformed due to an inflow of hydraulic oil to between the low-rigidity disk and a disk adjacent thereto according to an increase in a pressure in a cylinder upper chamber during an extension stroke, and can improve the durability of the low-rigidity disk.

公开(公告)号：US20230296158A1

公开(公告)日：2023-09-21

申请号：US18023174

申请日：2021-09-13

Applicant: Hitachi Astemo, Ltd.

Inventor： Hirohito ISHII ,  Takao NAKADATE ,  Osamu YUNO ,  Yuta YAMAGUCHI

IPC: F16F9/516 ,  F16F9/348 ,  F16F9/19

CPC classification number: F16F9/516 ,  F16F9/348 ,  F16F9/19 ,  F16F2222/12 ,  F16F2232/08 ,  F16F2234/02 ,  F16F2228/066

Abstract: A shock absorber is configured in such a manner that a flow passage area of each of first orifices 169 and 189 is smallest throughout a communication passage that establishes communication between a chamber 2A or 2B on an upstream side and a chamber 2B or 2A on a downstream side, and therefore prevents a pressure in a back-pressure chamber 55 or 26 from excessively increasing. As a result, the shock absorber can prevent overshoot of a damping force due to a delay of valve opening of a main valve 53 or 23 due to a remaining pressure in the back-pressure chamber 55 or 26 when a movement of a piston 3 is switched from one direction to an opposite direction.

公开(公告)号：US20220099153A1

公开(公告)日：2022-03-31

申请号：US17423330

申请日：2020-01-10

Applicant: Hitachi Astemo, Ltd.

Inventor： Osamu YUNO ,  Takao NAKADATE ,  Shunsuke MORI ,  Yu ISHIMARU

IPC: F16F9/348 ,  F16F9/46

Abstract: Provided is a shock absorber in which a check valve seated on a seat portion (second seat portion) having an annular shape is quickly opened during a reverse stroke. As a result, a working fluid in a chamber on a downstream side can be quickly introduced into a back-pressure chamber. Hence, a delay in response of a damping force, which may be caused by sticking of the check valve to a relief valve, can be suppressed.