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:
Jun. 16, 2020
Filed:
Sep. 28, 2016
Hitachi Construction Machinery Co., Ltd., Taito-ku, Tokyo, JP;
Atsushi Nakamura, Hyogo, JP;
Koji Shimazaki, Hyogo, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A work vehicle includes: a main hydraulic pump that supplies pressure oil to a hydraulic cylinder; an accessory pump that supplies pressure oil to an auxiliary machine; and a confluence switching valve that merges pressure oil of the accessory pump with pressure oil of the main hydraulic pump. The work vehicle is provided with a control device that, in case atmospheric pressure or air density of outside air is lower than a predetermined value, executes confluence limitation control of reducing a confluence flow rate at the confluence switching valve compared to the time in case the atmospheric pressure or the air density of the outside air is higher than the predetermined value, and canceling the confluence limitation control in case rotation speed of an engine becomes higher compared to a predetermined rotation speed value during the confluence limitation control, and the rotation speed value is higher as the atmospheric pressure or the air density of the outside air is lower.