Hydraulic system for working machine
US9051712B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 2010 |
| Grant date | Jun 9, 2015 |
| Priority date | — |
| Expiry date | Feb 17, 2032 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/6316
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A hydraulic system for a working machine is provided in which when heavy load fine speed operation work is performed using hydraulic cylinders as hydraulic actuators, and deterioration of fuel consumption can be prevented by reducing energy loss and improving fine speed operability. A center bypass cutoff valve 41 is disposed downstream of a center bypass line 26, and pressure sensors 42, 43, a controller 44, and a solenoid valve 45 provide control such that, when operating means 16 corresponding to a boom cylinder 5 (specific hydraulic actuator) among a plurality of operating means 18-21 is operated to supply a hydraulic fluid to a cylinder chamber 5a of the boom cylinder 5 in a load retaining side, the center bypass cutoff valve 41 is actuated and a fluid delivery pressure of a first hydraulic pump 2 is increased to be higher than a load pressure of the boom cylinder 5.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.