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:
Nov. 15, 2022
Filed:
Feb. 12, 2020
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Takamasa Kai, Tokyo, JP;
Juri Shimizu, Tokyo, JP;
Kenji Hiraku, Tsuchiura, JP;
Hiromasa Takahashi, Tsuchiura, JP;
Teppei Saitou, Tsuchiura, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
To provide a construction machine that has a hydraulic system mounted thereon in which a closed-circuit pump, and an open-circuit pump and a proportional valve are arranged as a pair, and that makes it possible to use an unused open-circuit pump or proportional valve to accelerate the speed of a single rod hydraulic cylinder when the single rod hydraulic cylinder and a hydraulic motor are driven simultaneously. A controller () controls a cap-side selector valve () and a rod-side selector valve () such that a particular open-circuit pump () not connected to a single rod hydraulic cylinder () is connected to the single rod hydraulic cylinder, and controls an opening area of a particular proportional valve () provided on a flow line that connects a delivery port of the particular open-circuit pump to a tank, when the single rod hydraulic cylinder and a hydraulic motor () are driven simultaneously.