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. 13, 2018
Filed:
Oct. 15, 2013
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
HITACHI CONSTRUCTION MAHINERY CO., LTD., Tokyo, JP;
Abstract
During boom-midair lowering operation in which a front work implementcan be turned under the self-weight of a boom, a hydraulic pump/motoris operated as a motor to operate a generator/electric motoras a generator. Power generation operation is performed by the hydraulic fluid discharged from a bottom-side chamberof a boom cylinderto recover positional energy. During jack-up in which the front work implementcannot be turned under the self-weight of the boom, the generator/electric motoris operated as an electric motor to operate the hydraulic pump/motoras a pump. The jack-up is performed by supplying the hydraulic fluid from the bottom-side chamberto rod-side chamberof the boom cylinderwithout supplying the hydraulic fluid from the main pumpto the rod-side chamberof the boom cylinder