The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 10, 2024
Filed:
Feb. 12, 2020
Hitachi Astemo, Ltd., Hitachinaka, JP;
Mikio Yamashita, Hitachinaka, JP;
HITACHI ASTEMO, LTD., Ibaraki, JP;
Abstract
A damping force adjustable shock absorber includes a flow path (an oil passage of a piston) in which a flow of hydraulic fluid is generated due to a movement of a piston rod, and a damping force adjustment valve provided in the flow path and configured to be subjected to an adjustment of an opening/closing operation by a solenoid. A frequency adaptive mechanism is provided in the flow path in series with the damping force adjustment valve. The frequency adaptive mechanism is configured to reduce a damping force for a high-frequency vibration. The frequency adaptive mechanism includes a second valve mechanism (a compression-side damping force generation valve and an extension-side damping force generation valve) configured to apply a resistance force to a flow of the hydraulic fluid from an upstream-side chamber (an upper-portion chamber or a lower-portion chamber) to a downstream-side chamber (the lower-portion chamber or the upper-portion chamber).