Robert Boschgmbh

Ulrich Schill

Hakan Camurdan

Michael Schuette

Benjamin Rosenbaum

Hermann Schuele

Joerg Spang

Alex Glavak

A pump assembly has a displacement volume that is continuously adjustable by a double-acting control cylinder having first and second control chambers, to which first and second receiving bores, respectively, are assigned. A pressure control valve in the form of a built-in valve is installed in one of the receiving bores and a 3/2-way switching valve in the form of a built-in valve is installed in the other of the receiving bores. The pressure control valve and the 3/2-way switching valve are each electrically adjustable and are connected to a control device. A target conveying pressure difference can be specified to the control device, and the control device is configured such that, by controlling the pressure control valve and the 3/2-way switching valve, the control device adjusts the displacement volume so that the difference between the first and second actual pressures approaches the target conveying pressure difference.

Flexible pump assembly for use in a fan drive

A hydraulic drive for a drilling apparatus includes a hydraulic motor that drives a drill and is connected to a main pump via a first and a second working line in a closed hydraulic circuit. The main pump has a steplessly adjustable displacement volume that is adjustable by an actuating cylinder that is connected to a control valve, which has a first feed connector and a first return connector. The first feed connector is connected to an outlet connector of a pressure reducing valve such that the pressure at the feed connector is adjustable to a predefined setpoint pressure by means of the pressure reducing valve. The setpoint pressure is set in a manner which is dependent on a desired high pressure in the closed circuit.

Hydraulic drive in front of a drilling apparatus

Growing community of inventors

Ulm, Germany

Ulrich Schill