Dr. Johannes Heidenhain Gmbh

Johannas Heidenhain Gmbh

Norbert Kerner

Frieder Kohler

Georg Zehentner

Michael Rauth

Helmut Schlick

Hans Lengenfelder

Eugen Kellner

A closed-loop control structure for positioning a load with the aid of an electric motor includes a device for the active damping of unwanted, low-frequency vibrations. The closed-loop control structure has a position controller, a speed controller, and a current controller, which together, form a cascaded control loop. Damping signals which counteract unwanted, low-frequency vibrations are applied to the control loop, at least one first and one second damping signal of different phase angle being derived from a single sensor signal, and the first damping signal being injected between the position controller and the speed controller, and the second damping signal being injected between the speed controller and the current controller.

Closed-loop control structure for damping low-frequency vibrations

A method for the start-up of a numerical control of machine tools or production machinery, wherein the numerical control includes a main computer and a follow-up device, which are connected with each other via a data transmission network, wherein the follow-up device is addressable by the main computer via a logical address and a hardware address, with information regarding a physical address of the follow-up device in the data transmission network, is allocated to the logical address. The method includes sequentially requesting in a set-up mode of operation of the main computer allocating information regarding a logical address and a hardware address from an operator for the follow-up device and other follow-up devices to whose logical address no hardware address had been allocated. The method further including storing the logical address and the hardware address in a memory unit after the allocating information has been performed.

Method for the start-up of numerical controls of machine tools or production machinery and numerical control for machine tools or production machinery

A control structure for the active damping of low-frequency oscillations in numerically-controlled machine tools. The control structure includes an rpm regulator having a proportional component and an integral component. The control structure further includes an active damping element that forms a low-frequency correction signal, which is phase-shifted with respect to an interfering low-frequency oscillation and free of d.c. components, and a summing point that is upstream or downstream of the integral component and receives the low-frequency correction signal.

Control structure for the active damping of low-frequency oscillations in numerically controlled machine tools

A method for determining the mass moment of inertia of an electric motor drive system of a machine, having a drive motor and further drive elements arranged downstream of the drive motor. The method includes a) determining a compensation current, which compensates losses occurring at a constant speed of the motor, so that a motor speed of the drive motor remains constant and b) determining an acceleration current, which generates a defined acceleration of the drive motor when the losses occurring at the constant speed of the drive motor are compensated. The method further entails c) calculating a mass moment of inertia of the electric motor drive system based on the determined acceleration current.

Method for determining the mass moment of inertia of an electric motor drive system

Based on the realization that, at the instant a holding brake in the drive of a machine tool is actuated, it may not be necessary to precisely observe the setpoint values, it may be provided to adapt control parameters in the controller of the drive such that, given an engaged holding brake, oscillations may be avoided or substantially reduced. By applying a correction value to the controller, it may be possible to prevent the adaptation of the control parameters from resulting in a change at the output of the controller.

Method for actuating a holding brake

A method for determining at least one time constant of a reference model, which is designed as a 2nd order time-delay element of a machine. The method includes detecting an oscillation frequency of an undamped machine oscillation and determining an optimized value of a time constant of the reference model as a function of the detected oscillation frequency of the undamped machine oscillation.

Method for determining time constants of a reference model in a cascade controlling circuit

A circuit configuration for monitoring machine parameters of a numerical controller for a machine tool where the circuit configuration includes a first processor calculating a first checksum and a third checksum, a first memory assigned to the first processor and has a bidirectional connection with the first processor, wherein the first memory stores machine parameters, a second processor calculating a second checksum and a fourth checksum, a second memory that has a bidirectional connection with the first processor and the second processor and a comparator connected to the first and second memories and the first and second processors, the comparator comparing the first and third checksums with one another and the second and fourth checksums with one another.

Method and circuit configuration for monitoring machine parameters

A system is described for reliable monitoring of clock rates, where a first processor which receives a first clock rate causes a counter to count using this first clock rate. A second processor which receives a second clock rate also causes another counter to count using the second clock rate. The readings of the counters are stored by the processors at predefined intervals in a common memory. Subsequently each of the processors loads the counter reading of the other processor, and compares it with its own counter reading. If both readings are within a tolerance range, one of the counter readings is used as a reference for all the other counters and the other counter readings are made equal to this reference value, so that subsequent monitoring of the processors is based on this reference value for the respective counters. If a reading is outside the tolerance range, an error is triggered.

METHOD AND CIRCUIT ARRANGEMENT FOR USING TWO PROCESSORS TO READ VALUES OF TWO INDEPENDENTLY CLOCKED COUNTERS, EXCHANGING VALUES THEREBETWEEN, COMPARING TWO VALUES TO DETERMINE ERROR WHEN THE COMPARISON EXCEED A THRESHOLD

A circuit arrangement for monitoring the operational state of an electric motor that includes an angle encoder mechanically connected with an electric motor. A first processor electrically connected to the angle encoder, wherein the first processor includes a first comparator that receives an output signal from the angle encoder. A second processor electrically connected to the angle encoder, wherein the second processor includes a second comparator that receives the output signal from the angle encoder. A shutoff component connected to the first and second processors to receive output signals from the first comparator and the second comparator, wherein the shutoff component shuts off the electric motor should an error be detected in either one of the output signals of the first and second comparators during a testing interval.

Method and circuit for monitoring the operating condition of electric motors

A filter module inserted into a speed control loop to shorten the rise time of the loop. The filter parameters of the filters provided in the filter module and the controller parameters are calculated in such a way that instances of resonant rise. The amplification factors for the proportional controller branch and the integral controller branch are increased, which leads to a shorter rise time.

Method and circuit arrangement for automatically parameterizing a quick-acting digital speed control loop

A method for determining optimum controller parameters for a digital rotational speed control is described, in which various test signals are applied to a speed control loop and the resulting speed characteristic is determined. The speed characteristic is subsequently weighted with respect to rise time and transient response for various controller parameters, and the most favorable controller parameters are subsequently set in the controller of the control loop. The integral-action time of the control loop is used as a criterion in performing the weighting operation.

Method and circuit arrangement for determining an optimum gain for the integrator of a speed controller

A method for detecting optimal controller parameters for a digital speed control is proposed, wherein an rpm control circuit is charged with different test signals, and the resulting rpm progression is determined. This rpm progression is subsequently evaluated with respect to triggering time and transient response for different controller parameters, and thereafter the most advantageous controller parameters are set in the controller of the control circuit.

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Traunwalchen, Germany

Norbert Kerner