Title:
HYDRAULIC SYSTEM FOR CONSTRUCTION MACHINE
Document Type and Number:
WIPO Patent Application WO/2019/167890
Kind Code:
A1
Abstract:
This hydraulic system for a construction machine comprises: a pump which supplies working fluid to a hydraulic actuator; a control valve which has a bypass path and is positioned on a center bypass line extending from the pump to a tank; an unload valve provided to the center bypass line on the side downstream of the control valve; and a control device which controls the unload valve, wherein the control valve is configured such that, while an operation signal that is output from an operation device is rising from a prescribed value to a first set value, the opening area of the bypass path is larger than the opening area of the unload valve, and when the operation signal reaches or exceeds a second set value that is larger than the first set value, the opening area of the bypass path becomes 1/4 or less of the maximum opening area of said bypass path.
More Like This:
| JP3760842 | HYDRAULIC APPARATUS OF POWER VEHICLE |
| WO/2008/004589 | MOTOR CONTROL DEVICE FOR CONSTRUCTION MACHINE |
Inventors:
KONDO AKIHIRO
HATA NAOKI
HATA NAOKI
Application Number:
PCT/JP2019/007092
Publication Date:
September 06, 2019
Filing Date:
February 25, 2019
Export Citation:
Assignee:
KAWASAKI HEAVY IND LTD (JP)
International Classes:
F15B11/00; E02F9/20; F15B11/08
Foreign References:
| JP2005265016A | 2005-09-29 | |||
| JP2016169815A | 2016-09-23 |
Attorney, Agent or Firm:
PATENT CORPORATE BODY ARCO PATENT OFFICE (JP)
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