Hydraulic drive system for construction machine
US9890518B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 2013 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Oct 9, 2034 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/88
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
During boom-midair lowering operation in which a front work implement 130 can be turned under the self-weight of a boom 131, a hydraulic pump/motor 7 is operated as a motor to operate a generator/electric motor 10 as a generator. Power generation operation is performed by the hydraulic fluid discharged from a bottom-side chamber 5b of a boom cylinder 5 to recover positional energy. During jack-up in which the front work implement 130 cannot be turned under the self-weight of the boom 131, the generator/electric motor 10 is operated as an electric motor to operate the hydraulic pump/motor 7 as a pump. The jack-up is performed by supplying the hydraulic fluid from the bottom-side chamber 5b to rod-side chamber 5a of the boom cylinder 5 without supplying the hydraulic fluid from the main pump 2 to the rod-side chamber 5a of the boom cylinder 5.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.