Moog Gmbh

Hms-hybrid Motion Solutions, Gmbh

Achim Helbig

Werner Handle

Christoph Boes

Werner Haendle

Werner Händle

Tino Kentschke

Sascha Dany

Dirk Becher

Reiner Kohlhaas

Klaus Kirch

Udo Koelbl

Michael Sieber

Reiner Kohlhas

Werner HÄNDLE

Udo KÖLBL

Mattias RÖGNER

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 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 electro-hydrostatic drive for realizing a rapid movement during a rapid movement phase, a force-building movement during a force-building movement phase. The apparatus comprises a hydro-machine with variable volume and/or rotational speed, driven by an electric motor, for providing a volume-stream of a hydraulic fluid, a first cylinder with a piston chamber, an rod chamber, and a plunger rod, a reservoir, a pressure source, a relief valve, a check valve, a fluid connection between the piston chamber and the hydro-machine, a fluid connection between the rod chamber and the hydro-machine, a fluid connection between the piston chamber and the reservoir, a fluid connection between the rod-chamber-side port of the hydro-machine and the reservoir, a fluid connection, through the relief valve, between the reservoir and the pressure source. The relief valve is for pressure safety of the reservoir, and the check valve has a fluid connection from the pressure source to the rod-chamber-side port of the hydro-machine, during the rapid movement phase, a first part of the hydraulic fluid is piped through the fluid connection between the piston chamber and the hydro-machine and the fluid connection between the rod chamber and the hydro-machine, and a second part of the hydraulic fluid communicates through the fluid connection between the piston chamber and the reservoir, during the force-building movement phase, a first part of the hydraulic fluid is piped through the fluid connection between the piston chamber and the hydro-machine and the fluid connection between the rod chamber and the hydro-machine, and a second part of the hydraulic fluid is piped through the fluid connection between the rod-chamber-side port of the hydro-machine and the reservoir.

Apparatus for controlling the switch-over of hydraulic cylinders

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

An electro-hydrostatic drive for realizing a rapid movement and a force-building movement, comprising a hydro-machine with variable volume and/or rotational speed, driven by an electric motor, for providing a volume-flow of a hydraulic fluid, a first cylinder with a housing, a piston, a cylinder rod, and a first and a second cylinder chamber, a second cylinder with a piston, a cylinder rod, and a first and a second cylinder chamber, a moveable carrier plate, a pillar, and a clamping apparatus to clamp and/or unclamp the first cylinder to the pillar, where the hydraulic drive has a closed hydraulic circuit, which has, when run, a positive pressure above atmospheric pressure and which, by utilizing the hydro-machine, can pressurize either the first or the second cylinder chamber of the first cylinder and/or the first or the second cylinder chamber of the second cylinder. The moveable carrier plate is connected both to the first cylinder and to the second cylinder. For the force-building movement, the first cylinder is clamped, by the clamping apparatus, to the pillar and one cylinder chamber of the first cylinder is pressurized with the hydraulic fluid, and for the rapid movement, the first cylinder is unclamped, by the clamping apparatus, from the pillar and one cylinder chamber of the second cylinder is pressurized with the hydraulic fluid.

Apparatus and method for cylinder changeover with a mechanically lockable force-building cylinder

The present invention relates to an electro-hydrostatic system () with a hydraulic machine () which is driven by an electric motor () and has a variable volume and/or rotational speed for providing a volumetric flow rate of a hydraulic fluid, a differential cylinder () with a piston surface and with an annular surface, and at least one equalization container (), wherein the drive system () has a closed hydraulic circuit and during operation has an overpressure relative to the environment by means of the hydraulic machine () and/or a pretensioning source (), and the drive system () provides a movement of the cylinder in a first direction by means of a volumetric flow rate of the hydraulic machine () and a volumetric flow rate from the equalization container (), and provides a movement in a second direction by means of a volumetric flow rate of the hydraulic machine () and a volumetric flow rate into the equalization container (), and a power operating mode and a speed operating mode are provided with the differential cylinder ().

Electro-hydrostatic drive system

An electro-hydrostatic actuating drive has a variable-volume and/or variable-speed hydraulic machine, which is driven by an electric motor, for the provision of a volumetric flow of a hydraulic fluid. Furthermore, the actuating drive comprises a cylinder with a piston, a piston rod and a first piston chamber, a valve with a first position and a second position, which valve can be moved by a first hydraulic actuator into the first position and by a second hydraulic actuator into the second position, wherein the second position controls a greater volumetric flow of the hydraulic fluid than the first position, a sink, a main line which connects a first piston chamber of the cylinder to the sink and in which the hydraulic machine is arranged, an auxiliary line which connects the first piston chamber to the sink and in which the valve is arranged, a first control line to the first hydraulic actuator, and a second control line to the second hydraulic actuator. A hydraulic resistor is arranged in the main line in series with the hydraulic machine, the first control line is connected to the main line, and the second control line is connected between the hydraulic resistor and the first piston chamber.

Actuating drive having a hydraulic outflow booster

The invention relates to a hydraulic drive () comprising a working cylinder () and a travel cylinder () which is mechanically connected to the working cylinder (). The working cylinder () and the travel cylinder () each comprise an upper and a lower cylinder chamber (), and all four cylinder chambers () of the working and travel cylinder () are connected to one another in a suitable manner in a closed pressure circuit () which is filled and prestressed with a hydraulic fluid (F). A rotational speed-variable hydraulic machine () with a first and second pressure connection () is arranged in the pressure circuit () in order to conduct the hydraulic fluid (F) between the individual cylinder chambers () of the working and travel cylinder () during the operation (B) of the hydraulic drive (). At least one first and second distributing valve () are arranged in the pressure circuit () such that the respective valve switch positions () which are suitable for the different operating phases of the hydraulic drive () together with the suitably driven hydraulic machine () allow a common movement of the work and travel cylinder () in one or the other piston movement direction (R, R). For this purpose, preferably only the first and the second distributing valve () are arranged in the pressure circuit (). The hydraulic drive () requires a minimum number of components, maintains a low installation complexity, improves the energy efficiency, can be constructed in a compact manner, and can be operated in a sufficiently variable manner.

Hydraulic system

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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Stuttgart, Germany

Achim Helbig