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:
Oct. 28, 2014
Filed:
Jan. 05, 2012
Shinji Ishihara, Hitachinaka, JP;
Shinya Imura, Toride, JP;
Masatoshi Hoshino, Tsuchiura, JP;
Kazuo Fujishima, Tsuchiura, JP;
Shinji Ishihara, Hitachinaka, JP;
Shinya Imura, Toride, JP;
Masatoshi Hoshino, Tsuchiura, JP;
Kazuo Fujishima, Tsuchiura, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
Target rotation speed setup section for setting a target engine rotation speed; load detection for detecting a hydraulic pump load; an assist output computation section for calculating an assist output to be generated by a motor generator in accordance with a rotation speed deviation ΔN, which is the difference between an actual and target rotation speed, or in accordance with the hydraulic pump load; an absorption torque upper limit computation section for calculating an absorption torque upper limit value of the hydraulic pump; and an operation signal generation section for generating the operation signal to be output to a pump displacement adjustment device. When the rotation speed deviation ΔN is equal to or more than a setting NC determined in accordance with the assist output value, the absorption torque upper limit computation section reduces the absorption torque upper limit value of the hydraulic pump from the calculated value.