Moog Gmbh

Werner Handle

Achim Helbig

Christoph Boes

Reiner Kohlhaas

Sascha Dany

Tim Reidl

In summary, the invention relates to a device and method for open-loop or closed-loop control of a movement of a die cushion of a die cushion press. The device has a control value encoder (), a speed controller (), a current controller (), and a motor control device () for providing a nominal current for an electrical drive () of a fluid-hydraulic motor pump unit () for moving a die cushion of a die cushion press. The control value encoder () is provided in order to calculate a setpoint speed based on a die cushion control value command and a die cushion information. The speed controller () calculates a setpoint current based on the setpoint speed. The current controller () calculates a control signal based on the setpoint current, and the motor control device () calculates the nominal current based on the control current. In this respect, the dynamics of the control of the electrical machine can be improved.

Device and method for open-loop or closed-loop control of a movement of a die cushion of a die cushion press

The hydraulic system according to the invention is a hydraulic system for controlling a stabilizer drive, in particular for controlling an angle of attack and/or a pivoting out and in of a stabilizer wing, preferably for ships. The hydraulic system according to the invention has a rotary vane motor that changes the angle of attack of the stabilizer wing and/or a hydraulic cylinder for pivoting the stabilizer wing out and in, along with a first hydraulic circuit. The first hydraulic circuit furthermore comprises a low-pressure circuit and a high-pressure circuit, a device for providing an admission pressure of the low-pressure circuit, and two anti-cavitation valves which separate the first low-pressure circuit from the first high-pressure circuit. The hydraulic system according to the invention is furthermore characterized in that a first hydraulic pump driven by an electric motor and having two connections is integrated in the high-pressure circuit.

Hydraulic system for stabilizer drive

The hydraulic system according to the invention comprises a hydraulic circuit with a low-pressure region and a high-pressure region; a volume- and/or speed-variable hydraulic machine, which is driven by a first electric motor and has an inlet and an outlet and provides a volume flow of a hydraulic fluid in the high-pressure region of the hydraulic circuit. The hydraulic system according to the invention further comprises at least one movable shaft, which is arranged in the high-pressure region of the hydraulic circuit; at least one valve, which separates the high-pressure region from the low-pressure region; and at least one hydraulic fluid container, which is hydraulically connected to the low-pressure region of the hydraulic circuit. The hydraulic system according to the invention also has a discharge line, which discharges hydraulic fluid from the leakage of the hydraulic machine, and a cooling line for transporting the hydraulic fluid in order to cool the electric motor, the discharge line and the cooling line being fluidically connected to at least one of the hydraulic fluid containers.

Motor cooling via hydraulic fluid

An electrohydrostatic actuator system comprising: a volume- and/or speed-variable hydraulic machine which is driven by an electric motor, for providing a volumetric flow of a hydraulic fluid; a differential cylinder with a piston side and a ring side; and at least one pretensioning source. The actuator system has a closed hydraulic circuit, wherein, during operation, the hydraulic fluid in the hydraulic circuit is pressurized by means of the hydraulic machine and/or the pretensioning source. Furthermore, according to the invention, the differential cylinder provides a power motion operating mode and a rapid motion operating mode. In order to balance a volume of the hydraulic fluid in the closed hydraulic circuit, according to the invention an expansion reservoir is connected to the piston side of the differential cylinder via a valve.

Electrohydrostatic actuator system with an expansion reservoir

A safe hydraulic drive system and process, comprising at least one first cylinder chamber and a second, separate cylinder chamber which are connected to one another via a connecting line to form a fluid-filled hydraulic circuit, and a hydraulic drive for conveying the fluid from one cylinder chamber, via the connecting line, into the other cylinder chamber in which the connecting line is arranged. The connecting line has at least one parallel system, between the hydraulic drive and one of the two cylinder chambers, including at least one first sub-connection with at least one first stop valve and a second sub-connection with a baffle arranged therein. The connecting line, excluding the second sub-connection, has a first flow resistance and the second sub-connection has a second flow resistance due to the baffle arranged therein, which is greater than the first flow resistance for the fluid, wherein the drive system is provided with at least one open first stop valve in normal mode and with a closed first stop valve in safe mode for conveying the fluid, and a suitably high second flow resistance has been selected so that a maximum permissible speed for a piston rod is not exceeded in safe mode, even when an external force acts on the drive system in the direction of movement of the piston rod.

Safe-to-operate hydraulic drive

A fail-safe actuation system comprising an actuator having first and second chambers, a working circuit with a motor/pump device configured to actuate the actuator in an operative state, and a safety circuit configured to move the actuator into the safety position in a failure state, the safety circuit having a tank that holds pressurized fluid and that, in the failure state, is automatically connected to the first chamber via a switching valve, and having a drain valve that, in the failure state, is moved into a through-flow position in order to drain fluid out of the second chamber, the safety circuit configured such that, in the operative state, an inflow into the actuator&#x2014;in a manner that is decoupled from the tank&#x2014;is established by the working circuit, and, in the failure state, an inflow from the tank into the first chamber&#x2014;in a manner that is completely decoupled from the working circuit&#x2014;is created by the safety circuit, whereby a short-circuit fluid connection is provided between the first and second chambers that, in the failure state, is through-connected in order to generate a short-circuit flow between the first and second chambers.

Fail-safe actuation system

Disclosed is a fail-safe fluidic actuation system () having a safety position, comprising a control element () having at least one first and one second chamber (); having a working circuit () with a motor/pump device (), wherein the control element can be actuated by means of the working circuit at least in the operational state. Furthermore, the actuating system comprises a discharge valve () which, in a failure state, is placed into a pass-through position in order to discharge fluid from the second chamber, and the safety circuit is designed such that, in the operational state, an inflow decoupled from the store can be generated into the control element by means of the working circuit with the motor/pump device, wherein by means of the safety circuit, in a failure state, an inflow fully decoupled from the working circuit with the motor/pump device is provided into the first chamber by means of the store, wherein the control element has three chambers, and wherein the safety circuit is designed such that, in the operational state, an inflow decoupled from the store can be generated into the third chamber () by means of the working circuit with the motor/pump device.

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Marbach am Neckar, Germany

Werner Handle