DE102019000422A1 - Method for testing a drive system with a first brake and drive system - Google Patents

Abstract

Method for testing a drive system with a first brake and drive system, in particular wherein the first brake is mechanically coupled to the drive system and is electrically actuated by the drive system, wherein first a check of the drive system for diagnostic errors is performed, - and then a test of the first brake is performed.

Description

The invention relates to a method for testing a drive system with a first brake and a drive system.

The closest prior art is off DE19941121 C2 a method for testing the holding torque of a brake is known in which an electric motor is actuated when the brake is engaged with a defined torque and the machine axis must not move.

A brake here has two system states. In the released or opened state, the brake coil is supplied with current, thereby bringing the brake elements (eg brake shoes) into a position which does not affect the movement of the machine axis. In the sunken or closed state, the brake coil is de-energized. As a result, the brake elements, usually pressed by a mechanical spring against the machine axis, whereby a movement of this machine axis should be prevented. If the brake elements worn, for example due to wear, only a reduced holding torque can be transferred to the machine axis.

When checking the brake, this wear is detected by the fact that the defined torque of the electric motor is greater than the reduced holding torque of the worn brake, whereby a movement of the machine axis is detected. If a malfunction of the brake occurs during this test, the machine axis is shut down until the error has been rectified.

The machine axis of a drive system is understood to mean the complete musculoskeletal system, consisting of linear and / or rotary motion elements, which are driven by the electric motor of the drive system.

From the EP1710549B1 It is known to carry out a test of the holding torque repeatedly with increasing torques.

From the DE102010051413A1 a method for monitoring a braking distance is known. To test the brake, a drive system is required consisting of a variety of components that must cooperate properly. In addition to the brake itself, the system components also include at least one brake actuator, at least one position change sensor, at least one electric motor, at least one machine axis, a frequency converter, a safety controller and a system controller.

The brake actuator converts the control signals in the low-voltage range to a high-voltage motor voltage, which is needed to control the brake. The frequency converter controls or controls the electric motor, while the safety controller monitors the drive system for correctness and, if necessary, can safely influence the functions of the frequency inverter.

In this case, the system components are arranged so that both the brake and the position change sensor are mounted on the same machine axis of the electric motor, the position change sensor measures the movement of the machine axis and this information simultaneously provides the frequency converter and the safety controller.

The frequency converter usually has a safe pulse lock, which is operated by the safety controller. A safe pulse inhibit here is an apparatus that interrupts the pulse width modulated drive signals for the electric motor typically generated in the control or control part of the frequency converter, so that the power unit in the frequency converter is no longer able to generate signals that have a torque in the electric motor effect.

In addition, the system controller exchanges data with the frequency inverter and thus implements the interconnection and coordination of one or more axes required for the application.

From the WO2008 / 092581A1 a drive system is known in which a plant control operates a frequency converter.

From the DE 10 2010 051413 A1 an interconnection of drive system components for the test of a brake is known.

From the DE19941121C2 a drive system is known in which the brake is controlled by a system controller (PLC).

However, due to cost and technical feasibility, not all system components involved in the brake test are functionally safe.

From the DE 10 2005 037 189 A1 As the closest prior art, a method for the safe condition monitoring of a drive unit with multiphase motor is known.

From the DE 34 47 090 A1 For example, a method for controlling the brake of a motion-monitored drive motor in a printing machine is known.

From the DE 10 2010 011 788 A1 For example, a method of operating a drive system is known.

From the DE 10 2011 004 995 A1 is a vehicle known.

The invention is therefore based on the object to increase the validity of the test of the brake and thus to achieve a higher level of functional safety.

According to the invention the object is achieved by the method according to claim 1 or 10 and in the drive system according to the features indicated in claim 12.

In the present invention, the object is thus achieved by first checking the components of the drive system that are necessary for the test for faults and / or defects prior to the actual test of the brake. Among other things, it is ensured by means of suitable diagnostics that the brake can be controlled, the required torque can be applied by the electric motor, and the travel path required for the test is free.

Under free travel while the range of motion of the machine axis is meant. If the required travel path is not free because, for example, the machine axis is blocked, then this could be falsely recognized as a closed brake with correct holding torque.

• - dass zunächst eine Prüfung des Antriebssystems auf Diagnosefehler durchgeführt wird, insbesondere wobei die Erkennung eines Diagnosefehlers einen Fehlerzustand des Antriebssystems auslöst,
• - und dass danach eine Prüfung der Ersten Bremse ausgeführt wird, insbesondere wobei ein Fehlerzustand des Antriebssystems ausgelöst wird, wenn ein bei der Prüfung der Ersten Bremse von der Ersten Bremse erzeugtes Haltemoment ein Mindesthaltemoment unterschreitet,

insbesondere wobei Diagnosefehler diejenigen Fehler des Antriebssystems sind, die bei der Prüfung der Ersten Bremse das Haltemoment der Ersten Bremse größer als das Mindesthaltemoment, insbesondere fälschlicherweise, erscheinen lassen.Important features in the method for testing a drive system with a first brake,
in particular wherein the first brake is mechanically coupled to the drive system and is electrically controllable by the drive system, are

• - that first of all a check of the drive system for diagnostic errors is carried out, in particular wherein the detection of a diagnostic error triggers an error state of the drive system,
• - and that thereafter a check of the first brake is performed, in particular wherein a fault condition of the drive system is triggered when a generated during the test of the first brake by the first brake holding torque falls below a minimum holding torque,

in particular, wherein diagnostic errors are those errors of the drive system, which make the holding torque of the first brake greater than the minimum holding torque, in particular erroneously appear in the first brake test.

The advantage here is that before testing the brake is first checked as a test for diagnostic errors, if the machine axis around the measuring position around an obstacle, such as an end stop or an end position of the machine axis, and whether the drive can muster a sufficiently large moment at all.

Namely, if an obstacle falsifies the test of the brake or a defective or aged engine does not apply the torque, the test of the first brake is either not practicable or causes a wrong final result of the first brake test to be carried out subsequently.

• - die Erste Bremse geöffnet, insbesondere gelüftet, wird und der Maschinenachse ein Fahren einer ersten Strecke zu einer ersten Zielposition, insbesondere als Stillstandsposition, hin in eine erste Bewegungsrichtung vorgegeben wird,
• - wobei aus der Länge der ersten Strecke und aus im Antriebssystem hinterlegten Parametern, insbesondere aus einer maximalen Geschwindigkeits- und Beschleunigungsinformationen, eine erste Zeitdauer für das Fahren berechnet wird,
• - wobei nach Ablauf der ersten Zeitdauer die Position der Maschinenachse erfasst wird, wobei bei Überschreiten eines zulässigen ersten Maßes an Abweichung der Position von der ersten Zielposition oder bei sich noch in Bewegung befindlicher Maschinenachse ein Fehlerzustand des Antriebssystems ausgelöst wird,

in einem zweiten Verfahrensschritt

• - der Maschinenachse ein Fahren um eine zweite Strecke zu einer zweiten Zielposition, insbesondere als Stillstandsposition, hin in eine zweite Bewegungsrichtung vorgegeben wird,
• - wobei aus der Länge der zweiten Strecke und aus im Antriebssystem hinterlegten Parametern, insbesondere aus einer maximalen Geschwindigkeits- und Beschleunigungsinformationen, eine zweite Zeitdauer für das Fahren der zweiten Strecke berechnet wird,
• - wobei nach Ablauf der zweiten Zeitdauer die Position der Maschinenachse erfasst wird, wobei bei Überschreiten eines zulässigen ersten Maßes an Abweichung der Position von der zweiten Zielposition oder bei sich noch in Bewegung befindlicher Maschinenachse ein Fehlerzustand des Antriebssystems ausgelöst wird,

wobei die Länge der zweiten Strecke betragsmäßig kleiner als die Länge der ersten Strecke ist,
insbesondere wobei die Länge der zweiten Strecke der halben Länge der ersten Strecke entspricht und/oder wobei die zweite Bewegungsrichtung der ersten Bewegungsrichtung entgegengesetzt gerichtet ist.In an advantageous embodiment, the drive system comprises a machine axis,
in particular, wherein the machine axis can be moved by a motor which can be braked by the first brake to a respective axle position,
wherein the test of the drive system for diagnostic errors is performed by
in a first process step

• the first brake is opened, in particular released, and the machine axis is set to drive a first distance to a first target position, in particular as a standstill position, in a first direction of movement,
• wherein from the length of the first route and from parameters stored in the drive system, in particular from a maximum speed and acceleration information, a first time duration for the driving is calculated,
• - Wherein after the first period of time, the position of the machine axis is detected, wherein when exceeding an allowable first The degree of deviation of the position from the first target position or, with the machine axis still in motion, an error state of the drive system is triggered,

in a second process step

• the machine axis is preset to travel by a second distance to a second target position, in particular as a standstill position, in a second direction of movement,
• wherein a second time period for driving the second distance is calculated from the length of the second distance and from parameters stored in the drive system, in particular from a maximum speed and acceleration information,
• wherein after the second time period, the position of the machine axis is detected, whereby an error condition of the drive system is triggered when exceeding an allowable first degree of deviation of the position from the second target position or while still moving machine axis,

wherein the length of the second route is smaller in magnitude than the length of the first route,
in particular, wherein the length of the second distance corresponds to half the length of the first distance and / or wherein the second direction of movement is directed opposite to the first direction of movement.

The advantage here is that a free driving is performed around the position around, in which the test of the brake should be performed. This ensures that the area around the position, ie second target position, has no obstacle. It also ensures that the engine can apply a sufficiently large moment. For this purpose, a time period is determined based on the kinematic set points, which can only be maintained if the engine works in the desired and / or expected manner, so can apply a sufficiently large moment.

If the second distance is only half the size of the first distance and the free driving, ie the test for diagnostic errors has been passed, an equally large safety distance to any obstacles is advantageously achieved on both sides.

As soon as the second target position has been reached, in particular without errors having occurred, this position value, that is to say the second target position, is predetermined as the target of a position control of the machine axis.

In an advantageous embodiment, while the first and the second distance are being traveled, the speed of the machine axis is monitored for exceeding a threshold value,
in particular, when the threshold value is exceeded, an error state of the drive system is triggered. The advantage here is that with respect to the speed compliance a corresponding, relevant for the subsequent brake test diagnostic error is recognizable.

In an advantageous embodiment
After reaching the second target position, in particular at standstill, detected in a third process step with the brake open the axis position of the machine axis and is controlled to the target position, in particular a motor driving the frequency converter of the drive system is operated in position control, ie in particular the
actual position of the machine axis detected with a sensor is controlled to the second target position,
wherein an error condition of the drive system is triggered when an allowable second degree of deviation of the position from the second target position is exceeded,
wherein the second dimension is greater than the first dimension, in particular at least ten times greater than the first dimension,
wherein the second measure is smaller than the product of the time span and a maximum speed, in particular maximum drift speed,
Thereafter, an actual torque, ie an actual value of the torque, of the drive system of the machine axis is detected and an error condition is triggered when a permissible level of deviation of the detected actual torque from a predetermined desired torque is exceeded
and a speed of the machine axis or the drive system of the machine axis is detected and when exceeding the maximum speed, ie when exceeding an allowable third degree of deviation of the detected speed of zero, ie in particular from standstill, an error condition is triggered.

In this case, detection of the position change can be used as detection of the speed.

The advantage here is that is regulated to the second target position out while the engine is allowed to apply its maximum allowable torque. After opening the brake, the motor must therefore hold the load torque. If the associated target torque is undershot or exceeded, an error is triggered. Thus, a related diagnostic error is excluded for the subsequent brake test. Likewise, a drifting occurring in spite of the activated position control would trigger an error state from the second target position, so that a related diagnostic error is also excluded.

According to the invention, in this determination of the torque which is carried out during the position control, the machine axis may drift from the actually preferred measuring position as long as the drift speed remains low. For this purpose, in contrast to the previous position monitoring steps, the permissible degree of positional deviation is greatly increased, in particular more than one order of magnitude. During torque determination, therefore, the speed is monitored and at the same time position monitoring. The permissible degree of positional deviation is only limited by the fact that the free travel performed in the first and second process steps must be greater than the permissible level by the second position. Thus, drifting of the machine axis within the cleared area is allowed. The period of time for the measurement of the torque and the Maximum speed, in particular maximum drift speed, are specified accordingly.

Since the cleared area around the second position is the same size in both directions, the direction of the drift is irrelevant. Because when driving free the route is symmetrically freed around the second position around, where appropriate, a non-linear transmission ratio between motor angular position and track position, for example in a winch, is considered.

In an advantageous embodiment, the drive system comprises a frequency converter,
wherein the frequency converter and the machine axis are in operative connection,
wherein the frequency converter can be parameterized in different operating modes,
wherein an actual torque can be generated by means of a frequency converter,
wherein for checking the drive system for diagnostic errors
first the frequency inverter is parameterized to position control at standstill,
the first brake is opened,
then the actual torque of the frequency inverter is read out and compared with a desired torque stored in the drive system,
and at the same time the machine axis is monitored for standstill,
wherein a deviation of the actual torque from the target torque or an in-motion machine axis triggers a fault condition of the drive system. The advantage here is that the execution of the method is possible in a simple manner.

In an advantageous embodiment, it is monitored during the execution of the method whether a predetermined range of axial positions of the machine axis is left during the execution of the method, the range comprising the first path, in particular containing
in particular, when leaving the predetermined range, an error condition of the drive system is triggered. The advantage here is that it is ensured that the machine axis does not drift away from the second target position during the position control, thereby leaving the area around the second target position.

In an advantageous embodiment, the processing of the method is started by a signal from a user and / or an application. The advantage here is that the process can be initiated by the user as often as desired.

In an advantageous embodiment, the processing of the method is aborted immediately if another safety function requires a shutdown or a fault is detected in a component of the drive system,
wherein the safety functions differ by the monitoring of certain system and / or motion parameters of the drive system. The advantage here is that when executing the method detected errors lead to a demolition and thus accidents are avoidable.

In an advantageous embodiment, the drive system has more brakes,
wherein in the second step after reaching the second target position not only the first brake but also the other brakes are opened. The advantage here is that no disturbing braking torque is initiated by the other brakes

Important features in the method for testing a drive system with brakes are that each of the brakes is selected one after the other as the first brake,
wherein for each brake selected as the first brake, the aforesaid method is carried out. The advantage here is that a high level of security is achievable.

In an advantageous embodiment, an error state of the drive system is triggered when the last test of the holding torque of the brake is older than a parameterized test interval. The advantage here is that a very high level of security during operation is achievable.

Important features of the method for testing the brake, which has a drive system, wherein the drive system is mechanically coupled to the brake and the brake is electrically controlled by the drive system, are that first the drive system is checked for diagnostic errors and then carried out the test of the holding torque of the brake wherein the brake must apply a defined minimum holding torque, wherein diagnostic errors are those errors of the drive system, the brake torque, regardless of the actual holding torque at the time of testing, the detected holding torque appear greater than the minimum holding torque, and wherein the detection of a diagnostic error or a holding torque smaller than the minimum holding torque triggers an error state of the drive system.

In this case, minimum torque is a specified torque which the brake must be able to apply in order to counteract the rotational effect of the force of the electric motor and / or the machine axis and the components mechanically coupled thereto.

Advantageously, the increased diagnostic coverage, due to the testing of the drive system for diagnostic errors, higher safety characteristics can be assumed. This enhances the application for use with a higher risk profile.

The risk profile results from the severity of the possible injury, the frequency of operator exposure and the possibility of hazard prevention.

The application environment of the invention lies in plant and machine automation with increased time requirements. The invention is mainly used to avoid or reduce hazards that may arise through the system or the machine itself.

In a further advantageous embodiment, the drive system comprises a machine axis. In this case, to test the drive system for diagnostic errors, first traversing the machine axis by a first distance in a first direction of movement, then moving the machine axis by a second distance in a second direction of movement, in particular wherein the length of the second distance of half the length of the first distance corresponds in particular wherein the second direction of movement is opposite to the first direction of movement, wherein in each case a necessary time for the movement is calculated from the lengths of the first and the second distance and stored in the drive system maximum speed and acceleration information, in each case after expiration of this time checked Whether the respective route has been traversed exactly within technically feasible tolerances and the machine axis is at a standstill, and wherein a deviation of the distance traveled by the respective predetermined distance or one is still in motion machine axis triggers an error state of the drive system.

Advantageously, this ensures that the guideway on the one hand is free of obstacles and on the other hand is not driven against an end limit during the test of the brake.

By end limitation is meant the maximum, mechanical position of a machine axis in a direction of movement, beyond which, without damaging the system and / or machine, no movement is possible.

At the same time it is checked that the drive system is able to apply the required parameters such as torque and / or acceleration at all.

In a further advantageous embodiment, during the movement of the machine axis about the first distance and / or the second distance, the machine axis is monitored for a limited speed, wherein exceeding the speed triggers an error state of the drive system.

Advantageously, this ensures that the drive system does not exceed the maximum speed stored in the parameterized frequency converter.

In a further advantageous embodiment, the drive system comprises a frequency converter, wherein the frequency converter and the machine axis are in operative connection, wherein the frequency converter can be parameterized to different operating modes, wherein an actual torque can be generated by means of frequency converter. To test the drive system for diagnostic errors, the frequency converter is first parameterized to position control at standstill, then all existing brakes of the axis are opened, then the actual torque of the frequency inverter is read out and compared with the parameterized setpoint torque and at the same time the axis is monitored for standstill a deviation of the actual moment from the setpoint moment or an axis in motion triggers an error state of the drive system.

Advantageously, this verifies that the brake can be released, that the required torque can be generated by the drive system, and that a desired torque corresponding to the load is parameterized.

In a further advantageous embodiment, the execution of the method may only be started and / or executed in a defined area of the machine axis. Leaving the area during execution triggers an error state of the drive system.

Advantageously, the test is thus carried out only in a region of the machine axis and / or machine and / or system in which an error-free processing can be ensured by means of its mechanical structure.

In a further advantageous embodiment, the execution of the method is started by a signal from a user and / or an application.

Advantageously, the test is carried out only if error-free processing can be ensured by means of the operating state of the application. For example, performing the test within a processing cycle is not desirable, because the workpiece to be machined is damaged.

In a further advantageous embodiment, the processing of the method is aborted immediately when another safety function requires a shutdown or a fault in a component of the drive system is detected, with safety functions differ by the monitoring of certain system and / or motion parameters of the drive system.

Advantageously, the drive system is still functionally safe even during the test of the brake.

In a further advantageous refinement, the method is repeated individually for further braking on the machine axis and / or on further braking of a further machine axis.

Advantageously, the test of several brakes successively, whereby a mutual influence can be prevented.

In a further advantageous embodiment of the fault condition of the drive system is triggered when the last test of the holding torque of the brake is older than a parameterized test interval.

Advantageously, this ensures that the test of the brake is performed at regular intervals.

Important features of the drive system to perform the test of a brake are that the brake, the brake actuator and the position change sensor are safety-oriented and that data can be exchanged between the safety controller and the frequency converter.

Safety-related components are developed according to the functional safety standard, while safety-rated components are of conventional origin, but have been considered according to the functional safety standard and have been provided with related characteristic values. "Functionally safe" is to be understood as meaning that a single random or systematic error in a component and / or system does not, or only with a very low probability, lead to the application being dangerous and thus to the injury or death of humans, Pollution of the environment and / or the loss of a plant or production.

With regard to the features, it is important that the safety controller can monitor the electric motor by means of a frequency converter, and the electric motor can be moved by means of a frequency converter through the safety controller.

The motion control takes place via traversing commands from the safety controller. A traversing command is an order to the frequency converter to let the electric motor travel in a certain direction a defined distance and thereby apply a defined torque.

To monitor the electric motor, the safety controller reads current status values, such as the motor currents and / or motor torques, from the frequency converter. These are then compared against further movement information of the machine axis by a safe position change sensor and plausibility.

Important is the close integration of safety controller and frequency converter, as a safety controller is typically only able to monitor the system via sensors outside the frequency inverter and to shut down the frequency inverter in a safety-related manner when an error is detected.

The advantage of the present drive system is that the safety controller performs the "master" function to perform the brake test. By "master" function is meant that the safety controller temporarily receives complete control of the drive system. Thus, all necessary components can be controlled by means of the safety controller and the necessary status information can be called up.

In a further advantageous embodiment, the brake can be released or closed by the safety controller via the brake actuator, in particular so that it can be brought into engagement.

The advantage of this embodiment is again in the immediate control of the safety control via the brake.

Advantageously, non-safety-related components of a safety-related component can be used with the present drive system in order to reliably perform a plausibility check of a further safety-related component, in the present case a safety-rated brake. A plausibility check is the evaluation of default and readback values by checking whether these values match logically. The diagnosis is the detection of possible errors in the drive system.

Further advantages emerge from the subclaims. The invention is not limited to the combination of features of the claims. For the skilled person, further meaningful combination options of claims and / or individual claim features and / or features of the description and / or figures, in particular from the task and / or the task posing by comparison with the prior art arise.

The invention will now be explained in more detail with reference to figures.

In the 1 the sequence of the method according to the invention for testing a brake is shown.

In the 2 an exemplary drive system is schematically outlined, which is suitable for carrying out the method.

As in 1 shown, the drive system is in an operating state before the start of the test of the brake. The operating state is the state in which the system fulfills its operational function.

At the beginning of the procedure, it is first checked whether the start conditions are met. Thus, the test must be approved by a user or regularly by an application. This ensures that the execution of the test does not interrupt one cycle of processing.

Furthermore, the machine axis must be in an allowable range for the test. This ensures that running the test does not damage the equipment. If both start conditions are met, the drive system is first checked for diagnostic errors.

For this purpose, it is first ensured by retracting the axle that there are no obstacles in the way in both motor movement directions. This means that the machine axis is first moved by a first distance in a direction of movement and then by the second distance in a second direction of movement. Preferably, the length of the second distance corresponds to half the length of the first distance, and the second direction of movement is opposite to the first direction of movement. The necessary time for the traversing movement is calculated from the specified distance, the parameterized maximum speed and the parameterized maximum acceleration of the frequency inverter. If, at the end of this time, the distance has not been traversed exactly within technically feasible tolerances or the machine axis is still in motion, an error state of the drive system is triggered.

Next, the load torque test is used to test whether all the brakes involved can be released, if the required torque can be generated by the drive system, and if the correct setpoint torque adapted to the load has been parameterized.

For this, the frequency inverter is first parameterized to "position control at standstill", then all existing brakes on the machine axis are opened, then the actual torque of the frequency inverter is read out and compared with the parameterized setpoint torque. At the same time, the machine axis is monitored for standstill. A deviation of the actual torque from the parameterized desired torque or a machine axis in motion leads to the transition of the drive system in the error state.

If no errors are detected in both tests, the holding torque test is carried out.

For this purpose, first the holding torque of the brake is checked against the torque of the electric motor. The brake is first closed, the current actual position of the machine axis is read in and saved as start position. Thereafter, the electric motor is driven so that it generates a defined torque that is smaller than the expected holding torque of the brake. During this the current actual position is monitored. A difference in the actual position from the start position outside an allowable tolerance means that the brake no longer applies the necessary holding torque, which behavior leads the drive system into the error state.

Thereafter, the holding torque of the brake is checked against the moment of the load on the axle. For this the brake remains closed. The electric motor is switched torque-free via the safe pulse inhibit in the frequency inverter. Here, too, the current actual position is monitored and a difference of the actual position from the start position outside the permissible tolerance leads to the transition of the drive system in the error state.

If no errors are detected during the last two tests, the drive system returns to the operating state.

In the 2 is an exemplary implementation of a drive system consisting of safety control ( 1 ), Frequency converter ( 2 ), Brake actuator ( 3 ), Plant control ( 4 ), Electric motor ( M ), Machine axis ( A ), Brake ( B ) and position change sensor ( G ). The frequency converter ( 2 ) controls the electric motor in three phases ( M ) on. The control of the electric motor ( M ) is over a secure impulse lock ( 22 ) provided by the safety controller ( 1 ) is served, interruptible.

The electric motor ( M ) is by means of the machine axis ( A ) mechanically with the position change sensor ( G ) and the brake ( B ) coupled. The position change sensor ( G ) gives the motion information of the machine axis ( A ) in the form of electrical signals both to the frequency converter ( 2 ) as well as to the safety controller ( 1 ) continue. The information is provided by the frequency converter ( 2 ) for controlling the electric motor ( M ) and the safety controller ( 1 ) is used to monitor the correct operation of the drive system.

Both the frequency converter ( 2 ) as well as the safety controller ( 1 ) are connected to a higher-level system control ( 4 ) connected. The plant control ( 4 ) is capable of this via the frequency converter ( 2 ) the machine axis ( A ) in the superior function of the plant. Between plant control ( 4 ) and safety control ( 1 ) status information about the operating or safety state of the drive system and / or the system are typically exchanged.

In addition, the safety controller ( 1 ) with the frequency converter ( 2 ) via a communication interface ( 15 ) connected. Via this interface ( 15 ), the safety controller ( 1 ) in the function of the frequency converter ( 2 ) and status information of the frequency converter ( 2 ) read out.

In further development, the safety controller ( 1 ) via a secure digital output ( 13 ) by means of the brake actuator ( 3 ) are executed such that the brake is directly controlled. The necessary high-voltage voltage for controlling the brake ( B ) receives the brake plate ( 3 ) via an additional voltage output ( 24 ) on the frequency converter ( 2 ).

The invention thus relates to the further development of a method and a drive system for testing a brake. According to the invention, this object is achieved in that, before the actual test of the brake, first the system components necessary for the test are checked for faults and / or defects. Among other things, it is ensured by means of a suitable diagnosis that the brake can be controlled, the electric motor can apply the required torque, and the travel path required for the test is free. This additional fault diagnosis significantly increases the informative value of the brake test and, as a result, achieves a higher level of functional safety.

The following list of reference numerals is included in the description and explains further features of the invention.

LIST OF REFERENCE NUMBERS

1

safety control

2

frequency converter

3

skid plates

4

system control

11

monitoring unit

12

Interface for position change sensor

13

Safe output for brake control

14

Interface for controlling the safe pulse inhibit

15

Interface for communication between safety controller and frequency converter

16

Interface for communication between plant control and safety control

21

Control unit

22

Safe pulse lock

23

Interface for connecting the electric motor

24

Supply voltage for brake control

25

Interface for position change sensor

26

Interface for communication between system control and frequency converter

A

machine axis

B

brake

G

Change in position sensor

M

electric motor

S1

First travel route

S2

Second movement route

T

Calculated time duration

V

limited speed

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19941121 C2 [0002, 0014]
• EP 1710549 B1 [0006]
• DE 102010051413 A1 [0007, 0013]
• WO 2008/092581 A1 [0012]
• DE 102005037189 A1 [0016]
• DE 3447090 A1 [0017]
• DE 102010011788 A1 [0018]
• DE 102011004995 A1 [0019]

Claims (12)

Method for testing a drive system with a first brake, in particular wherein the first brake is mechanically coupled to the drive system and is electrically actuated by the drive system, characterized in that - first, a test of the drive system for diagnostic errors is performed, in particular with the first brake is open and / or the detection of a diagnostic error triggers a fault condition of the drive system, - and that thereafter, a check of the first brake is performed, in particular wherein the first brake is activated, so a collapse of the first brake is controlled and / or a fault condition of the drive system is triggered when a holding torque generated by the first brake in the first brake test is lower than a minimum holding torque, in particular wherein diagnostic errors are those of the drive system that exceeds the first brake holding torque in the first brake test thaltemoment, in particular erroneously appear. Method according to Claim 1 wherein the drive system comprises a machine axis, in particular wherein the machine axis has an electric motor with the first brake which can be fed by an inverter, in particular wherein the machine axis can be moved by a motor which can be braked by the first brake to a respective axle position, characterized in that the test of Drive system is performed on diagnostic errors by in a first step - the first brake is opened, in particular aired, and the machine axis driving a first distance to a first target position, in particular as a standstill position, is set in a first direction of movement, - Length of the first distance and stored from the drive system parameters, in particular from a maximum speed and acceleration information, a first time period is calculated for driving, - wherein after the first time period, the position of the machine axis detected w If a fault condition of the drive system is triggered when an admissible first degree of deviation of the position from the first target position or with the machine axis still in motion is exceeded, in a second method step, the machine axis is driven a second distance to a second target position, in particular as a standstill position, in a second direction of movement is predetermined, - wherein from the length of the second distance and stored in the drive system parameters, in particular from a maximum speed and acceleration information, a second time period for driving the second distance is calculated, - after the second time period has elapsed, the position of the machine axis is detected, an error state of the drive system being output when an admissible first degree of deviation of the position from the second target position or machine axis still in motion is exceeded is solved, wherein the length of the second route is smaller in magnitude than the length of the first route, in particular wherein the length of the second route corresponds to half the length of the first route and / or wherein the second movement direction of the first direction of movement is directed opposite. Method according to Claim 2 , characterized in that when the first brake is opened while driving the first and the second distance, the speed of the machine axis is monitored for exceeding a threshold value, in particular wherein when the threshold value is exceeded, an error condition of the drive system is triggered. Method according to one of the preceding claims, after reaching the second target position, in particular at standstill, detected in a third step with the brake open the axis position of the machine axis and controlled to the target position, in particular a motor driving frequency converter of the drive system is operated in position control, In particular, therefore, the actual position of the machine axis detected with a sensor is regulated to the second target position, whereby an error state of the drive system is triggered when an allowable second degree of deviation of the position from the second target position is exceeded, the second dimension being greater than the first dimension , in particular at least ten times larger than the first dimension, the second dimension being smaller than the product of the time span and a maximum speed, in particular maximum drift speed, then an actual torque, ie an actual value of the moment, of the drive system Ems the machine axis is detected and when an allowable amount of deviation of the detected actual torque from a predetermined desired torque is exceeded, an error condition is triggered and detects a speed of the machine axis or the drive system of the machine axis is and when exceeding the maximum speed, ie when exceeding an allowable third degree of deviation of the detected speed of zero, ie in particular from standstill, an error condition is triggered. Method according to one of the preceding claims, characterized in that the drive system comprises a frequency converter, wherein the frequency converter and the machine axis are operatively connected, wherein the frequency converter can be parameterized in different modes, wherein an actual torque can be generated by means of a frequency converter, wherein for testing the First, the frequency converter is parameterized on position control at standstill, the first brake is opened, then the actual torque of the frequency converter is read out and compared with a specified torque stored in the drive system, and at the same time the machine axis is monitored for standstill Deviation of the actual torque from the target torque or a machine axis in motion triggers an error state of the drive system. Method according to one of the preceding claims, characterized in that it is monitored during the execution of the method, whether a predetermined range of axis positions of the machine axis is left during the execution of the method, the range includes the first route, in particular contains, in particular when leaving the predetermined range, a fault condition of the drive system is triggered. Method according to one of the preceding claims, characterized in that the processing of the method is started by a signal from a user and / or an application. Method according to one of the preceding claims, characterized in that the processing of the method is stopped immediately if another safety function requires a shutdown or a fault in a component of the drive system is detected, the safety functions by the monitoring of certain system and / or or motion parameters of the drive system differ. Method according to one of the preceding claims, characterized in that the drive system comprises further brakes, wherein in the second method step after reaching the second target position not only the first brake but also the further brakes are opened, A method of testing a drive system with brakes, characterized in that each of the brakes is successively selected as the first brake, wherein for each brake selected as the first brake, the method according to any one of Claims 1 to 9 is performed. Method according to one of the preceding claims, characterized in that a fault condition of the drive system is triggered when the last test of the holding torque of the brake is older than a parameterized test interval. Drive system for carrying out a method according to one of the preceding claims, comprising - at least one brake, - at least one brake actuator, - at least one position change sensor, - at least one electric motor, - at least one machine axis, - a frequency converter, - a safety controller, - and a system controller, wherein the brake, the position change sensor and the electric motor are mechanically coupled by means of the machine axis, wherein the frequency converter drives the electric motor, wherein the frequency converter has a safe pulse lock, the position change sensor measures the movement of the machine axis and this information at the same time the frequency converter and the safety controller available provides, with the safe pulse inhibit of the drive is controlled by the safety controller, and wherein between plant control and frequency converter by means of a communication link data ausausc hbar, characterized in that the brake, the brake actuator and the position change sensor are designed safety-oriented, and between safety controller and frequency converter by means of a communication link data are exchangeable, wherein the electric motor is monitored by frequency converter by the safety controller, wherein the electric motor by means of frequency through the safety controller is movable, and wherein the brake by means of brake actuator by the safety controller is controlled.

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