Hydraulic control system for construction machine
US10400426B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 2015 |
| Grant date | Sep 3, 2019 |
| Priority date | — |
| Expiry date | May 11, 2036 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/761
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
Provided is a hydraulic control system for a construction machine, including: a control valve (31) for controlling supply and discharge of hydraulic fluid to and from an arm cylinder (4); an operation lever (6) for controlling the position of a spool of the control valve (31); a meter-out flow passage (34) for passing therethrough hydraulic fluid discharged from the arm cylinder; a variable restrictor (23a) provided in the meter-out flow passage; pressure sensors (41, 42) for detecting a magnitude of a negative load applied by an external force to the arm cylinder in a same direction as an actuation direction of the arm cylinder; and a controller (45) for reducing an opening area of the variable restrictor (23a) according to an increase in the magnitude of the negative load calculated with a detection value from the pressure sensors (41, 42).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.