Control system for load-sensing hydraulic drive circuit
US4967557A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 26, 1989 |
| Grant date | Nov 6, 1990 |
| Priority date | — |
| Expiry date | Jan 26, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/71
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Control system for a load-sensing hydraulic drive circuit comprising; at least one hydraulic pump; hydraulic actuators driven by the hydraulic pump; and a pressure compensated flow control valve between the pump and each of the actuators, for controlling a flow rate of fluid to each actuator in response to a control signal. The control system has first detection means for detecting a differential pressure between the pump delivery pressure and the maximum load pressure; second detection means for detecting the pump delivery pressure; first means for calculating a differential pressure target pump delivery amount Q.DELTA.p to hold the differential pressure constant; second means for calculating an input limiting target pump delivery amount QT based on at least a pressure signal from the second detection means and an input limiting pump function; third means for selecting one of the differential pressure target delivery amount Q.DELTA.p and the input limiting target delivery amount QT as a pump delivery amount target value Qo, and then controlling the pump delivery amount to not exceed the input amount QT; and fourth means for calculating a compensation value Qns to limit a total con…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.