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:
Apr. 12, 2022
Filed:
Aug. 10, 2018
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Yoshiyuki Takigawa, Tsuchiura, JP;
Kentaro Itoga, Tsukuba, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A hybrid work machine is configured with an engine, a hydraulic pump, a hydraulic actuator, a generator motorcoupled to the engine, an electric storage devicethat transmits and receives electric power to and from the generator motor, an engine controllerthat controls the enginebased on a target engine revolution speed, a power controllerthat controls action of the generator motor, a controllerthat controls the engine controllerand the power controller, and a target engine revolution speed change instructing device that give instructions on a change in the target engine revolution speed. The controllercontrols the engine controllerand the power controllerto act the generator motoras a generator until an actual revolution speed of the engineis reduced to a revolution speed corresponding to a target engine revolution speed after change if the target engine revolution speed has been changed to be lower while the engineis in an unloaded state. It is thereby possible to suppress noise of the engine in the case where the target engine revolution speed has been changed to be lower while the engine is in an unloaded state.