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:
Feb. 28, 2017
Filed:
Jan. 19, 2012
Shiho Izumi, Hitachinaka, JP;
Manabu Edamura, Kasumigaura, JP;
Kouichi Shibata, Kasumigaura, JP;
Manabu Sugiura, Tsuchiura, JP;
Takatoshi Ooki, Kasumigaura, JP;
Shiho Izumi, Hitachinaka, JP;
Manabu Edamura, Kasumigaura, JP;
Kouichi Shibata, Kasumigaura, JP;
Manabu Sugiura, Tsuchiura, JP;
Takatoshi Ooki, Kasumigaura, JP;
HITACHI CONSTRUCTION MACHINERY CO., LTD., Tokyo, JP;
Abstract
Both a hydraulic motor and an electric motor are provided for driving an upper swing structure. When the amount of electricity stored in a capacitor is appropriate, the upper swing structure is driven by both the hydraulic motor and the electric motor. When the amount of electricity stored in the capacitor exceeds an appropriate value, the mode is changed over to a mode in which the upper swing structure is driven only by the hydraulic motor, and an assist electric generation motor is assist-driven or engine-driven to thereby rapidly return the amount of electricity stored in the capacitor to an appropriate range. The capacity of the capacitor can be reduced, and the amount of electricity stored in the capacitor can be managed without losing the operability of swing motion.