Invention Grant
- Patent Title: Construction equipment pressure control valve
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Application No.: US14765586Application Date: 2013-02-05
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Publication No.: US09611870B2Publication Date: 2017-04-04
- Inventor: Man-Seuk Jeon
- Applicant: VOLVO CONSTRUCTION EQUIPMENT AB
- Applicant Address: SE
- Assignee: VOLVO CONSTRUCTION EQUIPMENT AB
- Current Assignee: VOLVO CONSTRUCTION EQUIPMENT AB
- Current Assignee Address: SE
- Agency: Harness, Dickey & Pierce, P.L.C.
- International Application: PCT/KR2013/000926 WO 20130205
- International Announcement: WO2014/123251 WO 20140814
- Main IPC: F15B13/01
- IPC: F15B13/01 ; E02F9/22 ; F16K11/07 ; F15B13/042

Abstract:
A pressure control valve for a construction machine is disclosed, which prevents self-weight descent of a working device due to leakage of hydraulic fluid in a neutral position of the working device. The pressure control valve for a construction machine includes a holding valve block having a pilot signal pressure port and a drain flow path formed thereon; a holding poppet having a back pressure chamber formed therein to intercept leakage of hydraulic fluid from the hydraulic actuator to the control valve in a neutral state; a first elastic member pressing the holding poppet and elastically biasing an intercepted path between the hydraulic actuator and the control valve; a piston sliding in the holding valve block when pilot signal pressure is input through the pilot signal pressure port; a pilot poppet shifted to drain the hydraulic fluid in the back pressure chamber toward a drain flow path of the control valve in response to movement of the piston; a second elastic member pressing the pilot poppet and elastically biasing an intercepted path between the back pressure chamber of the holding poppet and the drain flow path of the control valve; and an auxiliary drain path draining the leaking hydraulic fluid through a drain path of the holding valve block if the leakage of the hydraulic fluid occurs on a check valve that opens or closes the path between the back pressure chamber of the holding poppet and the drain flow path of the control valve.
Public/Granted literature
- US20150377259A1 CONSTRUCTION EQUIPMENT PRESSURE CONTROL VALVE Public/Granted day:2015-12-31
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