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.

Date of Patent:
Feb. 24, 2026

Filed:

Nov. 11, 2021
Applicant:

Hitachi Construction Machinery Co., Ltd., Tokyo, JP;

Inventors:

Tarou Akita, Tsuchiura, JP;

Yoshihiro Shirakawa, Tsukuba, JP;

Kohei Ogura, Tsuchiura, JP;

Mitsuhiko Kanehama, Kasumigaura, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E02F 9/22 (2006.01); F15B 11/16 (2006.01); F15B 20/00 (2006.01); F15B 13/042 (2006.01); F15B 13/043 (2006.01); F15B 21/08 (2006.01);
U.S. Cl.
CPC ...
E02F 9/2228 (2013.01); E02F 9/2282 (2013.01); E02F 9/2285 (2013.01); F15B 11/165 (2013.01); F15B 20/007 (2013.01); F15B 13/0422 (2013.01); F15B 13/043 (2013.01); F15B 21/087 (2013.01); F15B 2211/3116 (2013.01); F15B 2211/36 (2013.01); F15B 2211/6343 (2013.01); F15B 2211/6346 (2013.01);
Abstract

A work machine includes a flow control valve that controls a flow rate of a hydraulic fluid supplied to a hydraulic actuator, a center bypass line that introduces the hydraulic fluid from a pump through a center bypass passage section of the flow control valve into the tank, a bypass cutoff valve that controls an opening of the center bypass line, a solenoid proportional valve that generates a pilot pressure for controlling the bypass cutoff valve, a pilot valve that generates a pilot pressure for controlling the flow control valve on the basis of an amount of operation of an operation device, and a controller that controls the solenoid proportional valve on the basis of the amount of operation. The controller controls the solenoid proportional valve to reduce an opening area of the bypass cutoff valve according to an increase in the amount of operation in a case the amount of operation is less than a predetermined amount of operation, and controls the solenoid proportional valve to make the opening area of the bypass cutoff valve larger than the minimum opening area in a case the amount of operation is a maximum amount of operation.


Find Patent Forward Citations

Quick Actions:

Akita, Tarou. (2026). Work machine (U.S. Patent No. 12559910). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/12559910

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

Loading…