Load independent valve control for a plurality of hydraulic users

US5138837A · kind A · utility

Assignee

• Mannesmann Rexroth AG · DE

Inventors

• Bernd Obertrifter · Süderbrarup, DE
• Armin Stellwagen · Lohr am Main, DE

Key dates

• Filing date: Feb 26, 1991
• Grant date: Aug 18, 1992
• Expiry date: Feb 26, 2011

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T137/87185
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

For a load independent control of a plurality of simultaneously actuable hydraulic users, a throttle valve (pressure compensator) is assigned to the control valve of each user at a location downstream with respect to the metering orifice formed by said control valves; said throttle valve is subjected in opening direction to the pump pressure and in closing direction, via a shuttle valve, either to a load pressure of the respective user or to a pressure which is determined by the highest load pressure occurring for one of said users. Said highest load pressure which is reported by a shuttle valve chain is supplied as control pressure to a pressure reducing valve, the input side thereof being connected with the pressure line of the pump and the output side thereof being connected to control lines leading to the throttle valves assigned to the individual control valves and to the control line for the pump control. The control of the pump control as well as of the pressure compensators by means of the highest indirect load pressure LS to the pressure reducing valve has the advantage that for starting and changing of direction, respectively, the danger of a sinking of the user is avoide…