Search International and National Patent Collections

1. (WO2018084332) HYDRAULIC CONTROL SYSTEM FOR CONSTRUCTION MACHINE

Pub. No.:    WO/2018/084332    International Application No.:    PCT/KR2016/012543
Publication Date: Sat May 12 01:59:59 CEST 2018 International Filing Date: Thu Nov 03 00:59:59 CET 2016
IPC: E02F 9/22
F15B 11/16
Applicants: VOLVO CONSTRUCTION EQUIPMENT AB
볼보 컨스트럭션 이큅먼트 에이비
SON, Youngjin
손영진
AN, Sewan
안세완
Inventors: SON, Youngjin
손영진
AN, Sewan
안세완
Title: HYDRAULIC CONTROL SYSTEM FOR CONSTRUCTION MACHINE
Abstract:
The present invention relates to a hydraulic control system for a construction machine. More specifically, the present invention provides a hydraulic control system for a construction machine comprising: a hydraulic pump group that includes a first hydraulic pump, a second hydraulic pump and a third hydraulic pump; a main control valve (MCV) that includes a first spool group that controls the amount and the flow of pressurised fluid supplied from the first hydraulic pump and the second hydraulic pump and that includes an operation apparatus spool, a driving spool and a merging spool, a second spool group that controls the amount and the flow of pressurised fluid supplied from the third hydraulic pump and that includes a rotating spool, and a straight driving valve that is installed between the first spool group and the second spool group; a first pilot signal line that is connected to the operation apparatus spool and that provides a supply path for a pilot pressurised fluid that is applied in order to switch the operation apparatus spool; a second pilot signal line that is connected to the driving spool and that provides a supply path for a pilot pressurised fluid that is applied in order to switch the driving spool; and a direction changing valve that is installed on the second pilot signal line connecting the driving spool and a tank, that is connected to the first pilot signal line, and that is switched when the operation apparatus spool is switched so as to cut off the flow of a pilot pressurised fluid that is returning to the tank.