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:
Oct. 15, 2019
Filed:
Jan. 16, 2017
Hitachi Construction Machinery Co., Ltd., Taito-ku, Tokyo, JP;
Jun Okamura, Kasumigaura, JP;
Takeshi Kobayashi, Kasumigaura, JP;
Mitsuhiro Yoshimoto, Ibaraki, JP;
Kazuo Takiguchi, Moriya, JP;
Masakazu Andou, Tsuchiura, JP;
Yoshifumi Takimoto, Ushiku, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A main spool () has a throttle passage () that, when the main spool () moves to an axial other side against a first return spring () in a main spool insertion hole (), communicates a pilot pressure chamber () with a first tank port () and limits a flow amount of hydraulic oil to be discharged to the first tank port () from the pilot pressure chamber (). When the main spool () moves to the axial other side along the main spool insertion hole (), the throttle passage () communicates the pilot pressure chamber () with the first tank port () before a state where a first pump port () is communicated with an output port () and a state where the output port () is blocked from the first tank port ().