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:
Jul. 18, 2017
Filed:
Sep. 11, 2012
Teruo Akiyama, Kokubunji, JP;
Noboru Iida, Chigasaki, JP;
Kenji Oshima, Koto-ku, JP;
Kenji Sasano, Hiratsuka, JP;
Teruo Akiyama, Kokubunji, JP;
Noboru Iida, Chigasaki, JP;
Kenji Oshima, Koto-ku, JP;
Kenji Sasano, Hiratsuka, JP;
KOMATSU LTD., Tokyo, JP;
Abstract
An operating state determining unit determines whether a hydraulic cylinder is in operation or not in operation. A discharge pressure reducing unit reduces the discharge pressure of a charge pump. A discharge pressure control unit controls the discharge pressure reducing unit when the hydraulic cylinder in not in operation to reduce the discharge pressure of the charge pump to a low pressure lower than a normal pressure. The normal pressure is the discharge pressure of the charge pump when the hydraulic cylinder is in operation. An accumulator is connected to a charge flowpath. A one-way valve is disposed between the accumulator and the charge pump. The one-way valve allows the flow of hydraulic fluid from the charge pump to the accumulator and prohibits the flow of hydraulic fluid from the accumulator to the charge pump.