FR2771785A1 - Procedure for recognizing faulty functions of clutch operated by drive, especially in drive train of car - Google Patents

Abstract

A procedure for recognizing faulty functions of a clutch operated by a drive, especially in the drive train of a car, has the drive controlled by a control signal. The pulse width of the control signal is determined or measured. The position and/or the speed of a component operated by the drive is determined. A parameter like the pulse width of the control signal is determined or measured, the position and/or the speed of a component operated by the drive is determined, the measured parameter, like the pulse width, and/or the position and/or the speed is/are compared with setpoints and with a deviation exceeding a specified value between the setpoints and the measured values, an error signal is generated. An Independent claim is also included for a device to carry out the above procedure.

Description

 The invention relates to a method for identifying faulty operations of an automated clutch actuated by means of an actuator, in particular an electric motor, in particular in the drive chain of a motor vehicle. The invention further relates to a device for implementing the method.

 For some time now, there has been an increasing interest in automated clutches. In connection with manual switching transmissions or automated transmissions, such clutches greatly improve driving comfort. In addition, a reduction in consumption is obtained since, owing to the lower expense linked to a gear change, actuation is carried out more frequently at a favorable speed from the consumption point of view. In connection with automated manual switching transmissions, one obtains, with such clutches, the comfort of usual automatic transmissions, without this increase in comfort being linked to an increase in consumption, as is generally the case in transmissions. conventional automatic with hydrodynamic torque converters.

 Automated clutches have certainly reached a high level of development and are extraordinarily reliable. However, a common check of its operational safety during operation and during a diagnosis in the case of after-sales service is of great importance.

 The object of the invention is to indicate a method for identifying faulty operations of a clutch actuated by an actuator, in particular in the drive chain of a motor vehicle, by means of which faulty operations can be identified, in a safe way and without significant additional expenses. The invention further aims to create a device for implementing the method.

 According to one aspect of the invention, this problem is solved in accordance with the invention using a first method for identifying faulty operations of a clutch actuated by means of a drive device, in particular in the chain. driving a motor vehicle, the drive device being controlled by means of a control signal, characterized in that the pulse duration of the control signal is determined or measured and the position and / or the speed of a component actuated by the drive device is determined.

According to a second aspect, the problem is also solved in accordance with the invention using a method for identifying faulty operations of a clutch actuated by means of a drive device, in particular in the drive chain of a motor vehicle, the drive device being controlled by means of a control signal, characterized in that a quantity, such as the pulse duration, of the control signal is determined or measured, that the position and / or the speed of a component actuated by the drive device is determined, that the measurement variable, such as for example the pulse duration and / or the pressure and / or the speed of the component, is compared with set values and that in the event that a deviation between the set values and the measurement values exceeds predetermined values, a fault signal is produced. Therefore, since a quantity, such as the pulse duration, and a geometric quantity of the movable component moved by the electric motor are used to identify faulty operations, no additional sensor is necessary, and on the contrary faulty operations can be identified by means of pure software programs, which are memorized in a control unit used to control the automated clutch or which are introduced from the outside into the control unit during a diagnosis, by means of a diagnostic device.

 According to a third aspect, the problem is solved according to the invention using a method for identifying faulty operations of a clutch actuated by means of an electric motor, in particular in the drive chain of a motor vehicle, the electric motor being controlled by means of a signal modulated according to a MID modulation, characterized in that the pulse duration of the MID modulation signal is measured, the position and / or the speed of a component actuated by the electric motor is determined, and the measured pulse duration and / or the position and / or the speed of the component are compared with setpoints and, in case a deviation between the setpoints and the measured values exceeds values predetermined, a fault signal is produced. Since the pulse duration and a geometric magnitude of the component moved by the electric motor are used to identify defective functions, no additional sensor is necessary, but defective functions can be identified by pure software programs which are memorized in a control device for controlling the automated clutch or are introduced from the outside into the control device, during a diagnosis, using a diagnostic device.

 According to another characteristic of the invention, the component approaches its setpoint position by regulating the MID modulation signal, that the pulse duration of the MID modulation signal is measured and is compared with a setpoint and that , when a predetermined deviation is exceeded, a fault signal is produced.

 According to another characteristic of the invention, the difference is equal to the absolute value of the difference between the set value and the measurement value (actual value).

 According to another characteristic of the invention, a position, which is reached before the set position is reached and for which the pulse duration of the modulation signal MID greatly increases, is fixed as a new set position.

 According to another characteristic of the invention, at least the set value of the MID modulation signal depends on the temperature of the drive device, for example an electric motor, and the temperature is measured by means of a sensor or is calculated .

 Using the method described, it is possible to diagnose faulty operations, such as for example the overload of the electric motor due to a hard actuation in the transmission path of the electric motor to the clutch, of a clutch stop. defective, broken compensation spring, etc.

 The problem according to the invention can be resolved using another method for identifying faulty operations of a clutch actuated by an actuator, in particular in the drive chain of a motor vehicle, the actuator being adjusted in such a way so that a component, which it moves, reaches a predetermined setpoint position, characterized in that the duration, which requires the actuator to move the component to bring it into a setpoint position, is measured and that fault signal is produced when this duration exceeds a predetermined value. Thanks to this process, it is possible, for example, to identify a defective stop, which may be attributable to different causes.

 According to another aspect of the invention, another method is provided for identifying faulty operations of a clutch actuated by an actuator, in particular in the drive chain of a motor vehicle, the actuator being adjusted so that a component, which it moves, reaches a predetermined target position, characterized in that the position of the movable component is constantly detected and that a final position, which differs from the target position, is fixed as a new position for setpoint, when this final position is maintained beyond a predetermined duration.

 According to another characteristic of the invention, the voltage of the voltage source for the electric motor or the actuator is measured and is taken into account when calculating quantities influenced by the voltage.

 Furthermore, it is appropriate to use as a determined control signal a setpoint control signal fixed and / or predetermined by a control unit.

 A device for implementing the methods according to the invention is further provided in accordance with the invention, characterized in that it comprises a clutch, an actuator for actuating the clutch, at least one sensor for detecting the position. of a component actuated by the actuator, a control apparatus comprising a microprocessor and a memory device and which controls the actuator according to programs stored in the memory device, and produces a fault signal in the event of a difference between the sensor signals and / or the power sent to the actuator and the set values.

 The methods are implemented in the device by programming the known program memories present in the microprocessor.

Other characteristics and advantages of the present invention will emerge from the description given below taken with reference to the appended drawings, in which
- Figure 1 shows a diagram of a clutch actuated using an actuator;
- Figure 2 shows a block diagram for controlling the actuator of Figure 1;
- Figure 3 shows a displacement sensor contained in the actuator of Figure 1;
- Figure 3a shows a representation of an actuator comprising a displacement sensor;
- Figure 4 shows a circuit for controlling an electric motor contained in the actuator of Figure 1;
- Figure 5 shows characteristic curves of an electric motor contained in the actuator of Figure 1;
- Figures 6 and 7 show diagrams; and
- Figure 8 shows a block diagram.

 In accordance with FIG. 1, an actuator, designated as a whole by the reference 18, for example an actuation unit, contains an electric motor 20 which drives, by means of a worm mechanism, an organ of crank drive 24 from which protrudes a rod 26 linearly guided, which is connected to a piston rod 28 which is part of the piston 30 of a master cylinder 32. A temperature sensor 33 is provided for monitoring the temperature of the electric motor 20.

 In another exemplary embodiment, the temperature can be determined or calculated using the sensor 33, by a clutch control unit actuated in an automated manner, using a mathematical model implemented, at which case one can use as input quantities for example individual quantities among the quantities indicated below to calculate the temperature of the actuator or of the electric motor: electric currents, voltages and powers, as well as thermal currents, fluxes arrival and departure times and heat capacities, as well as rotation speeds and torques. Using a model, which takes into account an incoming heat flow, an energy accumulation and an energy discharge, at any time the temperature of the actuator or the electric motor can be calculated using of a model.

 The rotational position and / or the rotational speed of the electric motor 20 and therefore the position / speed of the piston 30 is detected using at least one sensor 34, which is arranged for example in the form of an incremental sensor and delivers a pulse during a rotation of the worm, connected to the drive shaft of the electric motor 20, respectively over a predetermined angular value. The sensor can also be arranged in the form of an analog sensor, such as for example a Hall effect sensor, a potentiometer, an induction sensor, a plunger sensor or the like, which delivers an analog position signal during 'a displacement of the piston. Similarly an analog / digital converter and / or a microprocessor (ASIC) can be arranged downstream of the analog sensor, this converter and this microprocessor can also be arranged in the form of a construction unit. Consequently, the sensor can also be arranged in the form of an absolute distance sensor.

 The master cylinder 32 is connected via a pipe 35 to a receiving cylinder 36, in which a piston 38, the piston rod 40 of which actuates the actuating member 42 of a clutch 44.

The clutch 44 is located in the drive chain, not shown, of a motor vehicle between the drive motor and the transmission, the transmission being able to be actuated manually or possibly also to be automated. The clutch can be a traction clutch or, in another exemplary embodiment, can advantageously be a compression clutch. The clutch can also be a clutch with wear compensation or with backlash compensation or with reduction of the release force. These clutches control the operating point during the service life so that the wear which appears is compensated and that consequently the forces necessary during actuation of the clutch are substantially identical or vary only slightly during the period. clutch life.

 A non-return valve 46 is integrated in the piston 30. The wall of the master cylinder 32 has a sniffing hole 47, which is connected to a reservoir 48 for the hydraulic fluid. To obtain a relaxation of the stress applied to the electric motor 20 and / or its assistance with respect to actuation forces of the clutch 44, such as for example the clutch return spring, it is provided in the actuator 18 an expansion or compensation spring 49.

 Figure 2 shows in the form of a block diagram the control of the electric motor 20. The electric motor 20 is connected via a final stage 50 to a control device 52, which comprises a microprocessor 54 provided with an integrated working memory, a program memory circuit 56 and input / output interfaces 58. The control device has several inputs 60, to which the sensors 33 and 34 as well as other sensors are connected.

 A part of the electronic system of the control unit can be arranged in the form of a position regulator, which regulates the predetermined position of the clutch actuation system. This position regulator can be produced, in another embodiment, in the control program for controlling the clutch actuation system.

 To adjust or control the position of the actuator output element, as well as the master cylinder piston, a position regulator is used inside the control unit 52. This position regulator is produced in hardware form or preferably in software form and controls or regulates the engagement position of the clutch.

 FIG. 3 represents an exemplary embodiment of the sensor 34. To the drive shaft 62 of the electric motor 20 is connected, integrally in rotation, a pole wheel 64, which has magnetic poles having alternating polarizations along the periphery outside of the pole wheel. These magnetic poles move in front of a coil element 66, which delivers, on its terminals 68, a voltage pulse each time a pole passes in front of this element.

 FIG. 3a shows another embodiment of a position sensor 214, which is arranged inside the actuator 213.

The actuator consists essentially of the drive motor, such as the electric motor 212, the worm wheel 222, the connecting rod working in thrust 224, the piston 225 of the master cylinder and the master cylinder 211.

The electric motor 212 drives a worm not shown, which meshes with the tangent wheel 222 and drives it. The connecting rod 224 is articulated at the level of a stud on the tangent wheel 222. Under the action of the tangent wheel 222, the connecting rod is moved axially and consequently displaces the piston of the master cylinder. In addition, a force accumulator 226, such as a spring, is disposed inside the master cylinder to assist the electric motor 212. The master cylinder also has a connection 250, comprising an opening 251 and leading to a fluid reservoir.

The sensor 214 comprises a movable element 214a, which is connected by means of a stud to a tangent wheel 222, so that the element 214a is moved axially during a displacement of the tangent wheel. Thereby an element is moved in a plunger coil 214b and a signal, which corresponds to the position of the element 214a, is produced.

 FIG. 4 schematically represents the circuit of a final stage 50 used to control the electric motor 20. Four transistors 70, 72, 74 and 76 are connected, according to a bridge circuit, to the electric motor 20 so that the electric motor 20 is connected to the voltage source 78 according to the switching state of the transistors controlled by the control device 52, in one direction or the other or that the electric motor is separated from the voltage source. Consequently, both the direction of rotation and, by modulating the durations of the voltage pulses sent to the electric motor 20, the supply of voltage to this electric motor 20 can be controlled from the control device 52. The current and its direction of movement in the electric motor 20 can be measured by means of an ammeter measuring resistor 80.

 The arrangement of the described components and their cooperation are known and therefore will not be explained in detail.

 For the operational safety of an automated clutch of the type described, it is necessary to be able to identify in a simple and safe manner the most different disturbances on board a vehicle or during a diagnosis in an after-sales service workshop.

 The simultaneous exploitation of the MID modulation signal controlling the electric motor 20 and of the distance measurement carried out using the sensor 34 makes it possible to draw conclusions concerning the torque delivered by the electric motor 20 and therefore represents a possibility of identification of an overload. In addition, thanks to this exploitation of the signal, it is possible to identify the clutch stop, in which case the control can react possibly before a connection of the electric motor due to an overload.

 The electric motor 20, which is arranged as a DC motor, usually has a characteristic torque curve, which decreases linearly with the speed of rotation, as shown in FIG. 5, by a straight line represented by a continuous line , which represents the maximum power (100% MID of the electric motor for a temperature T1). If the pulse duration is reduced, for example by half (50% MID), the line represented as being continuous moves substantially in the same ratio of the lines represented by lines formed by dashes, in parallel in the direction of lower powers, since the reduction in the pulse duration also essentially means a reduction in the effective voltage.

 The relationship between the MID signal and the effective voltage Ueff is substantially linear as a first approximation.

 In the case of a temperature variation, the slope of the line varies as represented by the line in phantom, which illustrates the dependence of the speed of rotation n on the torque delivered M for a duration d pulse of 100% and for a temperature T2, which is higher than the temperature T1.

 The speed of rotation n can be obtained directly from the signal from the sensor 34. The pulse duration of the MID signal can be determined in the control unit 52. The temperature of the electric motor 20 is detected using the sensor 33. If a sensor 33 is not provided, the temperature of the electric motor can be calculated using a mathematical model, which is implemented inside the control unit. The temperature is therefore present in the form of a data set inside the control unit.

 FIG. 6 represents a diagram, on which the current I of the electric motor has been plotted as a function of the torque M. Curve 101 and curve 102 represent current curves as a function of cost, which are recorded for different temperatures T1 and T2. The curve 101 is recorded for a temperature T2 greater than the temperature T1 for which the curve 102 is recorded. The curves for variation of the current as a function of the torque therefore vary as a function of the temperature.

 FIG. 7 represents a diagram in which the load torque Mcharge of the electric motor or of the clutch drive device actuated in an automated manner has been represented, as a function of the actuation stroke. The actuating stroke is represented in the form of the angle of the armature, the actuating stroke can also be represented in millimeters. The armature angle is only a variant representation, a conversion factor existing between the angle and the displacement stroke. Curve 110 represents the variation for an actuator without compensation and curve 111 a variation with compensation. The compensation is carried out in the embodiment by a force accumulator, which is arranged so as to assist the electric motor at least over part of the actuating stroke.

Under the action of the compensating spring, the characteristic curve of variations 11 is shifted in the direction of the y axis and there is a distribution of the load Mcload of the motor so that the latter works in traction in a partial range and in compression in another partial range, the level of the torque being however overall reduced.

FIG. 8 represents a block diagram 300, in which the blocks of the clutch control unit 301, of the position regulator 302, of the memory 303, of the fault identification unit 304 and of the electric motor 305. Blocks 301 and 304 can be
implemented inside the control unit or can be produced in the form of individual groups. The control unit 301, the position regulator 302 as well as the fault identification unit 304 can be produced respectively in hardware or software form inside the control apparatus. The memorization takes place in an E2PROM memory. The electric motor 305 actuates, for example, the clutch automatically, by means of a transmission connected downstream, not shown.

 The clutch control unit 301 receives a series of input signals 306, such as, for example, sensors or other electronic units, such as, for example, an engine control unit, an ABS control unit. and / or other units. The clutch control unit 301 calculates, on the basis of these data, the clutch setpoint position KposiUon setpoint (307), which is transmitted via the output to the position controller 302 and to the the fault identification unit 303. The position regulator 302 is arranged in the form of a PID regulator or another regulator. The position regulator controls or adjusts the position of the clutch or the torque that can be transmitted by the clutch, based on the setpoint position K setpoint of the clutch and the actual position Actual position of the clutch , which it receives via a sensor.

 The actual position is set to the position that can be predetermined by means of the control difference between the setpoint position and the actual position.

 As input signals, for example, at least the following signals are available: engine rotation speed, transmission rotation speed, accelerator pedal position, throttle valve position, gear shift lever position , transmission ratio position, engine torque, clutch torque that can be transmitted, clutch engaged position, etc.

 The actual Kpositjon actual position of the clutch is determined by a sensor, which determines the actual engaged actual position of the clutch.

In FIG. 8, this sensor is integrated in the engine block so that the real Kposiuon value (309) is present at the output of the engine block 305 and is transferred to the position controller and to the fault identification unit. 303.

The position controller 302 receives the setpoint signal and the actual signal and thereby forms a control signal 308, with the help of which the motor is controlled, for the execution of the actuation as a function of the setpoint. . The motor actuates the clutch, which is indicated by arrow 309. The position regulator sends for example a signal
MID for motor control. In addition, the position controller can deliver an actuation direction, so that the correct actuation direction is controlled.

 The control signal 308 is also transmitted, via the signal 308a, to the fault identification unit 303.

The fault identification unit, for example, compares the setpoint with the actual value and determines the fault. The fault signal 310 is transmitted both to the control unit and to the fault memory 304 and is stored in this memory in a non-volatile manner. The clutch control unit can control an emergency backup operation strategy based on the presence of the fault signal. Storing in a non-volatile memory has the advantage that during a subsequent reading of the fault memory, it is possible to identify which fault, for example, appeared and when (in the event that the instant of the presence of the fault is stored).

 By way of example, it is mentioned that despite the power supply to the actuator, when a fixed stop is reached, the setpoint and the actual value do not coincide since, due to the stop, the actual value is unchanged and a difference from the set value is maintained.

Below, we will explain the examples of faulty operations, which can be determined in a simple manner by means of the exploitation of said measurement signals and of a comparison of the signals with reference values with reference to algorithms stored in the program memory 56:
1) Overload in the case where a conductor 35 is bent or in the case where the piston 30 or 38 is blocked or the like.

 In the case of the faults indicated above, the electric motor 20 must apply an intense force to achieve the desired displacement of the piston 30. The pulse duration of the MID signal is therefore very great without the electric motor 20 reaching its speed of usual rotation. The arrangement of the actuator 18 is such that it normally develops approximately three times the force which is necessary for actuating the clutch. When the pulse duration permanently exceeds a threshold value of for example 66% and the rotation speed of the motor 20 is permanently lower than a threshold value of for example 33% of the mobile speed, this implies a load not greater than the normal case and which is evaluated as a fault display which is displayed by a display unit, which is connected to the control unit 52 and which can be located in the dashboard of the vehicle, or may be contained in a diagnostic device, not shown, which can be connected to the control device 52.

Once a threshold value has been reached, a deviation of a quantity from the previously stored reference value can also be detected and be stored in the form of significant deviations.
it is obvious that very low outside temperatures can lead, due to the high viscosity of the hydraulic fluid, to increased adjustment forces, so that this case is advantageously excluded for diagnosis.

 Consequential faults of the defective operations indicated above are for example an excessively high control temperature, an error in the association of the position of the piston 30 with the position of the actuating member 42 (due to sealing faults ) as well as a disconnection of the electric motor 20 due to an overload.

2) Mechanism with difficult actuation inside the actuator 18:
Likewise in this case the electric motor 20 is subjected to a high above-average stress during operation. The fault can be determined, in the case of a factory diagnosis, by the fact that, when the piston rod 28 is blocked, during the return of the push rod 26 against the force of the compensating spring 45, a MID signal is obtained which is greater than a set value. Similarly, this faulty operation can lead, in the case of normal operation, to a temperature
Another possibility to diagnose a faulty clutch bearing is as follows
When a setpoint position of the clutch (defined for example by a predetermined setpoint stroke at the sensor or else the number of pulses of the sensor 34) cannot be obtained and the clutch meets before a stop, a warning signal is produced in the case of a long pulse duration and in the case of a slow stop or movement, which is determined by means of a sensor 34, at the end of 'a predetermined time interval for the control unit to make arrangements. After the expiration of another predetermined duration, the electric motor 20 is disconnected as protection against an overload.

3b) Identification of the stop in the driving operation
For specific constructions of the clutch, in particular in the case of clutches with automatic backlash, the position of the stop moves according to the wear of the linings. When the setpoint of the stop position is not corrected correspondingly, this leads to a faulty operation since it is not possible to approach the set stop, and the clutch comes in stop previously. This stop is identified by the fact that the electric motor 20 no longer turns despite a long pulse duration of the MID signal. If this state is maintained for a predetermined time interval, a warning bit can be set (the actuator cannot adjust the setpoint stroke). In addition to or instead of the warning bits, the preset value for the stop or the fully open clutch position can be set to the actual system position. This acts against disconnection of the electric motor 20 due to an overload since, under the effect of updating or adjusting the set value, the actual value reaches the set value , which leads to disconnection of the electric motor 20 since the set position is reached.

 During maintenance work, the adaptation of the set point can be read in a test or diagnostic device and is available for checking the clutch. Therefore one can perform a stop identification in a test mode. The test mode can be activated by a special activation of the control unit and is not used for the normal control of the automated clutch when the vehicle is moving.

 For diagnostic purposes, a program unit, which extends the setpoint stroke of the piston 30 of the master cylinder 32 from the "clutch open" position (the clutch still continues to open), is activated in the control device 22 using a test device. As soon as the overload warning appears, the actual stroke reached is memorized by this part of the program and the setpoint stroke is reduced so that there is no longer any risk of overload. The actual stroke thus determined or a quantity derived therefrom (for example the result of a comparison with a threshold or a clutch replacement indication) is delivered by the program unit to the test device or to the diagnostic device.

4) Compensating spring 49 broken
This faulty operation can be identified by an unusually high load on the electric motor 20 when the clutch is opened (displacement of the piston 30 to the right) or by an unusually low load on the electric motor 20 when the clutch returns. the clutch in the closed state. A consecutive fault also resides here in the fact that the temperature of the electric motor 20 can be too high in operation, which can lead to an automatic disconnection of the electric motor 20.

 The malfunctions indicated can be determined by means of corresponding programs or algorithms installed on board and stored in the program memory 56 of the control unit 52, or else within the framework of a factory diagnosis using a diagnostic device connected to the control device 52.

5) Diagnosis of faulty operations using average value signals:
By means of a formation of the mean value of current signals, it is possible in principle to obtain a continuous force signal. The average value of the current can be measured in the control unit or obtained or calculated from the ratio of the pulse durations of the current supply circuit, the actual voltage of the battery 78 and the resistance R of the electric motor 20, which is a known function of the temperature of the motor. With the continuous signal, it is possible to measure the clutch stop and the characteristic curve of the clutch force displacement stroke and compare the latter to a characteristic displacement - force characteristic curve. The diagnostic possibilities are therefore extended to the following example, or to deviations from the target characteristic curve compared to this actual characteristic curve.
stop corresponding to the stroke: the clutch is worn or defective,
stop within stroke limits: hydraulic section blocked,
pressure too low: section containing air, i.e. the clutch does not open,
no pressure: component failure, section showing leakage, no clutch / clutch faulty,
high pressure: bad clutch, no backlash.

 The invention is not limited to the use of electric motors modulated according to a pulse width modulation in the actuator. This has no direct relation to the measurement of the pulse duration, and the invention can also be used for other types of control of electric motors or hydraulic actuators.

 In the case of a method for identifying defective functions of a clutch actuated by means of an electric motor, in particular in the drive chain of a motor vehicle, in which the electric motor is controlled by means of a MID signal , the pulse duration of the MID signal is measured and the position and / or the speed of a component actuated by an electric motor is determined The measured pulse duration and / or the position and / or the speed of the component are compared to set values. In the case of a deviation which exceeds a predetermined value, between the set values and the measured values, a fault signal is obtained. According to another method, the duration which is necessary for an actuator to actuate the clutch to bring a component to a set position is measured, a fault signal is produced when this duration exceeds a predetermined value. In another method, the position of the moved component is continuously detected and an end position, which differs from the set position, is fixed as a new set position when the end position is kept beyond a predetermined duration.

 The invention is not limited to the exemplary embodiments indicated in the description and, on the contrary, numerous changes and modifications are possible within the framework of the invention, in particular such variants concerning elements and combinations of elements or materials.

Claims (12)

 1. Method for identifying faulty operations of a clutch actuated by means of a drive device, in particular in the drive chain of a motor vehicle, the drive device being controlled by means of a control signal, characterized in that the pulse duration of the control signal is determined or measured and the position and / or the speed of a component actuated by the drive device is determined.  2. Method for identifying faulty operations of a clutch actuated by means of a drive device, in particular in the drive chain of a motor vehicle, the drive device being controlled by means of a control signal, characterized in that a quantity, such as the pulse duration, of the control signal is determined or measured, that the position and / or the speed of a component actuated by the drive device is determined, that the quantity of measurement, such as for example the pulse duration and / or the pressure and / or the speed of the component, is compared with reference values and that in the case where a difference between the reference values and the measurement values exceeds predetermined values, a fault signal is produced.  3. Method for identifying faulty operations of a clutch actuated by means of an electric motor, in particular in the drive chain of a motor vehicle, the electric motor being controlled by means of a signal modulated according to a MID modulation, characterized in that the pulse duration of the MID modulation signal is measured, the position and / or the speed of a component actuated by the electric motor is determined, and the pulse duration measured and / or the position and / or the speed of the component are compared with set values and, in the case where a deviation between the set values and the measured values exceeds predetermined values, a fault signal is produced.  4. Method according to any one of claims 1 to 3, characterized in that the component approaches its set position by regulating the MID modulation signal, that the pulse duration of the MID modulation signal is measured and is compared with a setpoint and that, when a predetermined deviation is exceeded, a fault signal is produced.  5. Method according to claim 4, characterized in that the difference is equal to the absolute value of the difference between the set value and the measurement value (actual value).  6. Method according to any one of claims 3 to 5, characterized in that a position, which is reached before the set position is reached and for which the pulse duration of the MID modulation signal increases greatly, is fixed as a new setpoint position.  7. Method according to any one of claims 1 to 6, characterized in that at least the set value of the modulation signal MID depends on the temperature of the drive device, for example the electric motor, and whether the temperature is measured by means of a sensor or is calculated.  8. Method for identifying faulty operations of a clutch actuated by an actuator, in particular in the drive chain of a motor vehicle, the actuator being adjusted so that a component, which it moves, reaches a position of predetermined setpoint, characterized in that the duration, which requires the actuator to move the component to bring it into a setpoint position, is measured and that a fault signal is produced when this duration exceeds a predetermined value.  9. Method for identifying faulty operations of a clutch actuated by an actuator, in particular in the drive chain of a motor vehicle, the actuator being adjusted so that a component, which it moves, reaches a position of predetermined setpoint, characterized in that the position of the movable component is constantly detected and that an end position, which differs from the setpoint position, is fixed as a new setpoint position, when this end position is maintained beyond of a predetermined duration.  10. Method according to any one of claims 1 to 9, characterized in that the voltage of the voltage source for the electric motor or the actuator is measured and is taken into account when calculating quantities influenced by the voltage.  11. Method according to any one of the preceding claims, characterized in that there is provided as a determined control signal a setpoint control signal fixed or predetermined by a control unit.  12. Device for implementing the method according to any one of claims 1 to 3 and 5 or 6, characterized in that it comprises  a clutch,  an actuator for actuating the clutch,  at least one sensor for detecting the position of a component actuated by the actuator,  a control device comprising a microprocessor and a memory device and which controls the actuator according to programs stored in the memory device, and produces a fault signal in the event of a discrepancy between the signals from the sensor and / or the power sent to the actuator and set values.