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. 21, 2017
Filed:
Aug. 28, 2014
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Takako Satake, Ishioka, JP;
Shinya Imura, Toride, JP;
Kouji Ishikawa, Kasumigaura, JP;
Hidetoshi Satake, Ishioka, JP;
Shinji Nishikawa, Kasumigaura, JP;
Tomoaki Kaneta, Kasumigaura, JP;
Shiho Izumi, Hitachinaka, JP;
HITACHI CONSTRUCTION MACHINERY CO., LTD., Tokyo, JP;
Abstract
A work machine is adapted for reduced fuel consumption in regions where swinging by a hydraulic motor is prone to deterioration in efficiency, such as when the operating stroke of the swinging is small. The work machine includes an engine, a hydraulic pump, a swing structure, an electric motor for driving the swing structure, and a hydraulic motor for driving the swing structure, the hydraulic motor being driven by the hydraulic pump, and includes a swing control lever device that commands the swing structure to be driven. A control device operates in either an electric swing mode in which the swing structure is driven mainly by torque of the electric motor or a hydraulic swing mode in which the swing structure is driven mainly by torque of the hydraulic motor, depending on an operating stroke of the control lever device and/or a swing speed of the swing structure.