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:
Dec. 09, 2014
Filed:
Feb. 21, 2012
Nobuhiro Koga, Hiroshima, JP;
Nobuhiro Koga, Hiroshima, JP;
Kobelco Construction Machinery Co., Ltd., Hiroshima-shi, JP;
Abstract
A pump control device for a construction machine includes a pump regulator, a pump pressure detector, a travelling operation detector, a working operation detector, and a controller instructing the pump flow rate depending on the pump pressure to the pump regulator. The controller stores first and second P-Q characteristics as a horsepower characteristic and instructs the pump flow rate to the pump regulator, based on the first P-Q characteristic when a travelling operation is detected, and based on the second P-Q characteristic when a working operation is detected. The second P-Q characteristic is equal to the first P-Q characteristic in a low-pressure region while is one giving a low characteristic relatively to the first P-Q characteristic so as to increase a horsepower difference as the pump pressure increases, in intermediate-pressure and high-pressure regions.