Hydraulic pressure control device of construction machine
US7520130B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 2004 |
| Grant date | Apr 21, 2009 |
| Priority date | — |
| Expiry date | Nov 15, 2025 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/7142
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic pressure control device of a construction machine enabling an increase in operability and working efficiency by suppressing a fluctuation in flow rates occurring before and after the switching of a merging-separating valve, in energy efficiency by accurately determining the switching timing of the merging-separating valve to suppress the pressure energy loss of a pressure compensating valve, and working efficiency in the compound motion of plural hydraulic actuators. When a controller determines that necessary flow rates of first and second hydraulic actuators are less than maximum discharge flow rate of each of first and second variable displacement hydraulic pumps when the first merging-separating valve is in a merging position, the switching of the first merging-separating valve is controlled so that firstly the first merging-separating valve is switched to a separating position and, after the switching is completed, the second merging-separating valve is switched.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.