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. 07, 2017
Filed:
Aug. 13, 2012
Teruo Akiyama, Kokubunji, JP;
Noboru Iida, Chigasaki, JP;
Kenji Oshima, Tokyo, JP;
Koji Saito, Fujisawa, JP;
Teruo Akiyama, Kokubunji, JP;
Noboru Iida, Chigasaki, JP;
Kenji Oshima, Tokyo, JP;
Koji Saito, Fujisawa, JP;
KOMATSU LTD., Tokyo, JP;
Abstract
A hydraulic driving system includes a hydraulic cylinder with a cylinder tube and a cylinder rod, a main pump, a hydraulic-fluid path, a charge pump, a stroke position detecting unit, and a pump control unit. The hydraulic-fluid path forms a closed circuit between a main pump and the hydraulic cylinder. The cylinder rod expands or contracts depending on how hydraulic fluid is supplied and exhausted to and from first and second chambers. The charge pump replenishes hydraulic-fluid in the hydraulic-fluid path. The pump control unit performs flow-rate reduction control in which the pump control unit reduces a suction flow rate so that a suction flow rate of the main pump is equal to or less than a maximum discharge flow rate of the charge pump when the stroke position becomes closer to a stroke end of the cylinder rod than a prescribed reference position during the flow rate reduction control.