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. 09, 2009
Filed:
Oct. 05, 2005
Kazunori Nakamura, Tsuchiura, JP;
Kouji Ishikawa, Kasumigaura, JP;
Nobuei Ariga, Tsuchiura, JP;
Hideo Karasawa, Tsuchiura, JP;
Yasuo Okano, Kasumigaura, JP;
Kazunori Nakamura, Tsuchiura, JP;
Kouji Ishikawa, Kasumigaura, JP;
Nobuei Ariga, Tsuchiura, JP;
Hideo Karasawa, Tsuchiura, JP;
Yasuo Okano, Kasumigaura, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A computing section computes a reference revolution-speed decrease modification amount DNLR; and multiplies an engine revolution speed modification gain KNL by a reference revolution-speed decrease modification amount DNL and then DNLR, to thereby compute an engine revolution-speed decrease modification amount DND based on input change of an operation pilot pressure, which is modified in accordance with DNLR. At the time when a lever operation input from an operation command unit is changed from full stroke to half stroke, if a pump delivery pressure is in a pressure range of a pump absorption torque control region Y where the pump delivery pressure is lower than that in a region X, the reference revolution-speed decrease modification amount computing sectioncomputes the modification amount DNLR to be 0, and therefore lowering of a target engine revolution speed with auto-acceleration control is not caused.