EP0974479B1 - Method for the regulation of motor driven adjusting device in motor vehicle - Google Patents

Description

The invention relates to a control method Motorized adjustment devices in motor vehicles according to the preamble of claim 1 or claim 14. The adjustment devices can for example, a window regulator, a sunroof adjustment or act as a seat adjuster.

From US-A-5,541,859 a method for Measure the speed of rotation of a rotating body known. In the procedure, teeth are made from a magnetic Material is detected as soon as it is rotated of the rotating body on a detection device to be led past. The time intervals between the Detection of adjacent teeth will pass used to determine the speed of rotation.

From US-A-5,404,673 is a window lifter with a Drive for lifting and lowering a window pane and with an anti-trap device known with the speed of the drive and thus the opening and closing speed the window pane as well as the direction of movement and position of the window pane can be detected. At the Pinching a body part or object between the The upper edge of the window pane and the door frame increase the load of the drive, and the drop in drive speed below a specified value leads to a shutdown and possibly reversing the drive and thus for stopping or opening the window pane.

Because when the window pane enters the door seal the complete closing of the window pane due to the increased resistance the drive speed up to If the drive comes to a standstill, the disc position recorded as accurately as possible and the pinch protection in the sealing area turned off.

For this are a position and a direction of rotation sensor intended. The direction of rotation sensor consists of a magnetic disk connected to the drive shaft with a Nordund South pole and two at an angle of 90 ° around the magnetic disc axis staggered Hall sensors that around emit offset sensor signals for a quarter period which the direction of rotation and thus the direction of movement Window pane is determined.

The position sensor consists of an annular, with the Drive shaft connected to alternating multipole magnets magnetized magnetic poles and two Hall sensors, which in the Distance of half a magnetic pole to each other are. The changes in magnetization detected by the Hall sensors with a rotation of the drive and thus the ring-shaped Multipole magnets are counted as a counter together with the sensor signals of the direction of rotation sensor supplied, the counting pulses depending on the direction of rotation of the Drive can be counted upwards or downwards and thus the Specify the respective position of the window pane.

The well-known drive control and anti-trap device needed to record the speed, direction of movement and position of the window pane two magnetic disks as a signal generator with four Hall sensors, the for Triggering of the anti-trap criterion by reducing the speed of the drive provided signal generator with a Pole change per revolution has only a low resolution.

For speed control of rotating drives or at a linear adjustment such as a seat adjustment to achieve a constant adjustment speed about the adjustment path is a high resolution Sensor system necessary to ensure short reaction times in the control process to enable. Partitioned is used for this Signal generators such as multipole magnets that however subject to tolerances which have a negative impact on the Control behavior can affect.

Is therefore used to increase the resolution when recording the speed of an electric motor is a multipole magnet as a signal generator used, the problem arises that with rotary magnets with more than two poles the distribution of the Pole on the magnet is not exactly symmetrical, but has an error of approximately 10% per sector. This error rate applies generally to all signal generators for speed detection sensors, that are not manufactured precisely enough can and with an optoelectric, inductive, capacitive Work the sensor etc. as a signal receiver.

The tolerances described and manufacturing-related errors from section to section of the signal generator or from sector to sector with a circular disk-shaped signal generator lead to misinterpretations in signal evaluation. For example, due to misinterpretation Decreased speed, although the Drive is operated at constant speed and possibly to incorrect reactions of the control device the adjusting device, for example to reverse the error a window pane due to a faulty one Detection of a speed decrease by an anti-trap device is interpreted as a trapping event.

The object of the present invention is a method for the control and regulation of motor-driven adjustment devices in motor vehicles to create one exact detection of position, speed or acceleration a drive with high resolution of the measured values, without particularly high accuracy requirements for the signal transmitter be put.

This object is achieved by a method with solved the features of claim 1.

The method according to the invention ensures a high level Resolution and accuracy of the measured values for recording the Position, speed or acceleration of a drive. There the tolerances in the subject of the present invention partition-related and in signal evaluation are taken into account, the measurement errors caused by production-related inaccuracies of the signal generator be greatly reduced or canceled so that use of signal generators without particularly high quality requirements and thus of less exact components in the Signal generation and detection is possible.

In particular, it is possible to use components whose Manufacturing accuracies are limited due to the system, such as for example the manufacturing accuracy, i.e. the sector size and magnetization strength of electromagnetic signal transmitters in connection with magnetosensitive components, such as for example detectors in the form of Hall sensors. at Signalers can tolerances in the partitions exist for detectors (in the form of one or more Sensors) in electrical tolerances, for example the hysteresis of the switching thresholds for Hall sensors.

High resolution devices can therefore be used with little technical effort Position, speed, speed or Acceleration controls can be realized.

The method according to the invention can be done by means of either electronic error correction as well as circuitry be carried out, for electronic error correction only a single sensor is needed.

In the case of electronic error correction, the tolerance-related characteristic properties of the signaling partitions preferably in a test movement of the signal generator determined.

Further preferred developments of the invention Process are by the features of claims 3 characterized to 12.

Additional requirements for a control method an adjustment device arise if, for example regulates the speed of a seat adjustment device shall be. In this case, next to the setting a constant speed (target speed) at the operating point the motor also has a smooth, vibration-free start-up Driving down the seat is important. The working point of the The motor of the seat adjustment device is taken into account the resonance frequencies of the drive motor, Adjustment gear and mechanical seat components existing Seat unit and the vehicle body set. In addition, requirements regarding speed of the seat to be adjusted and with regard to a reserve power reserve get noticed.

When starting and stopping an electric seat adjustment device must not disrupt the occupants' movements or noises from starting or stopping the Occur seat. In addition, it is gentle on the material Wear-free operation of the seat adjustment device as possible desirable.

According to another aspect of the invention, the object is a method for controlling motor-driven Adjustment devices in motor vehicles to create the on the one hand a precise detection of the position, speed and possibly acceleration of a drive at high Resolution of the measured values enables and on the other hand smooth, even start and stop of the adjustment device allowed.

This object is achieved by a method with solved the features of claim 14.

Thereafter, it is provided that after operating the drive motor initially tolerance-related characteristic values of the signal generator is determined and correction values are determined therefrom be used in evaluating the output signals of the detector assigned to the signal generator (in the form of a or several sensors) should be taken into account. By this process step becomes high resolution and Accuracy of the measured values for recording the position, speed or acceleration of the drive guaranteed. In particular possible measurement errors caused by production-related or other inaccuracies of the signal generator are largely eliminated. For more details on the realization this procedural step is based on the above statements referred to claim 1.

According to claim 14 it is also provided that at least the correction values during operation of the drive motor be adjusted as long as not a given one Termination criterion is met and that during the determination and adjustment of the correction values for intermediate results of these values and to determine controller parameters of the control algorithm can be used. Based on these The control of the drive motor can carry out further procedural steps insert early after its actuation. It is especially not necessary with the start of the scheme to wait until all correction values are determined have been used in the evaluation of the output signals of the Detector must be considered. Rather be here the early results of these Correction values used. This will start of the seat the deviation of the actual speed of the drive motor the adjustment device of the desired Speed minimized.

The adjustment of the correction values provided according to the invention means that the correction values have changed are achieved as not reaching a certain termination criterion with which the adjustment of the correction values has been completed becomes. For example, the correction values successively determined with increasing accuracy until a predetermined accuracy of the correction values is reached. In particular, this should also include the case be, in which the adjustment of the correction values during the total duration of activation of the adjustment device he follows. This corresponds to the termination criterion "maximum achievable accuracy ", i.e. the adjustment of the structural values is continued here for accuracy still increase. Alternatively, you could use this termination criterion also define as "canceling the adjustment of the Correction values at the end of the adjustment movement ".

A permanent improvement in the accuracy of the correction values is without further ado according to the teaching claimed here possible because the associated longer duration at early determination of the correction values the regulation is not prevented. Rather, they become Regulation also the provisional, less precise correction values used. Thus the adjustment of the correction values especially after reaching the working point of the drive motor are continued.

The correction values are preferably determined here automatically every time the engine of the Adjustment drive so that changes due to wear, Environmental influences or the like, always current can be taken into account. On the other hand, it is also possible, the correction values in certain, predetermined redetermine time intervals and in the meantime work with stored correction values.

The control algorithm itself can, for example, consist of one Recursively constructed, time-discrete PID controller with one Manipulated variable limitation and back calculation exist; such a Controller requires a set of three control parameters.

In a preferred embodiment of the invention after reaching the operating point of the drive motor the controller parameters newly set, i.e. it will be a new one Set of controller parameters selected. Usually will thereby "harder" after reaching the working point Controller parameters selected as when starting the drive, so that after reaching the working point of the engine only even smaller fluctuations in the speed can be tolerated than when starting the engine.

In a further development of the aforementioned embodiment of the The invention provides that the controller parameters only then be reset if both the working point of the Motors also achieved the adjustment of the correction values is completed. In this case, the reassessment means the controller parameters after reaching the operating point of the engine that this fixing is final and no further changes were made to the controller parameters as long as the engine is at its operating point with its Target speed works. Even if after another Variant of the invention even after reaching the working point the correction values of the motor without limitation be further adapted, so it is generally advantageous after reaching the working point with new, to work harder controller parameters.

After reaching the working point of the engine will also to control the speed, preferably the pulse width modulation ratio used.

After the motor is triggered, its speed is preferred with an essentially constant acceleration elevated. The change in speed over time then forms a straight; the motor is thus up along a "ramp" ramped up to its working point. Deviations from the given the desired target speed by the slope of the ramp when starting the engine, the Correction described above corrected.

As long as the correction values are not yet sufficient Accuracy has been determined after triggering of the drive motor, the speed preferably by averaging over several each representing the speed of the engine Signals determined. Here, in particular moving averages are used. By this averaging can be tolerance-related fluctuations the speed information of the signal generator at least partially eliminated. At the same time, however, the Real-time content of the speed information.

The method according to claim 13 can in particular with a signal generator to be executed, the partitioning has, the correction values for compensation of tolerances that result from this partitioning are. An example of such a partitioned The signal generator is a multipole magnet that is connected to the drive shaft of the motor of the adjusting device connected and moves along with it. Tolerances can here, on the one hand, in the expansion of the individual segments of the multipole magnet occur and on the other also to different Switching thresholds of the north-south and the South-north transitions of the multipole magnet his. The latter are particularly popular with digitization of the signal generated by the signal generator. The correction values are used in such a signal generator So on the one hand, production-related fluctuations in the Compensate for the expansion of the individual partitions of the signal generator, and secondly to eliminate inaccuracies referring to the transitions between the individual partitions of the signal generator.

In the aforementioned embodiment of the invention also clearly that by averaging over the signals that successively from different partitions of the signal generator generated, the accuracy of the speed information can be increased. So in the case of a multipole magnet even when averaging over one north-south and one South-north transition to different switching thresholds at least considerably reduced inaccuracy become. If necessary, however, the averaging can also over a larger number of values, e.g. over four or eight values.

With a signal generator with the drive shaft of the motor is connected and therefore rotates together with it, can be provided that for each partition of the signal generator a separate correction value in the form of a correction of the determined rotation angle assigned to each partition is so that the corrected rotation angle is the actual Extend the partition along the perimeter of the auto switch represent.

The present invention is independent of which Principle of the auto switch that operates the rotation signal representing the motor. The signal generator can in particular be based on a magnetic, inductive, capacitive, resistive or optical principle work.

In particular comes as a magnetic signal generator Multipole magnet in question by one together with the Drive shaft of the motor rotating, multi-pole magnetic disc is formed. The one generated by the multipole magnet magnetic signal can be in a known manner Detect Hall sensors. Both when applying the magnetic as well as inductive or capacitive In addition, gear disks are also produced one representing the rotation of the drive shaft Signals in question. To generate optical signals, the one Finally, can represent rotary motion of the motor a signal transmitter provided with slots may be provided, which is then transparent to an optical signal, if one of the slots is between a light source and a receiver assigned to the light source.

The signal generator can also be part of the electromechanical System of the drive motor of the adjusting device be such as when using the collector of a commutator motor, of the coil system of a commutatorless motor or the piezo element of a piezo motor as a signal generator.

Furthermore, the motor current itself can also act as a signal generator serve if this for determining the speed contains the necessary information, for example for commutator motors.

Further advantages of the invention will be apparent from the following Description of exemplary embodiments with reference to the figures become clear.

Fig. 1 -

einen Signalgeber und einen zugeordneten Detektor zur Ausführung des erfindungsgemäßen Verfahrens;

Figuren 2 bis 4 -

verschiedene Kennlinien motorisch angetriebener Verstelleinrichtungen von Kraftfahrzeugen, anhand derer die toleranzbedingten charakteristischen Eigenschaften der Partitionen eines Signalgebers gemäß Fig. 1 ermittelbar sind;

Fig. 5 -

eine zweite Ausführungsform eines Signalgebers und eines zugeordneten Detektors zur Ausführung des erfindungsgemäßen Verfahrens;

Fig. 6 -

eine Darstellung der Ausgangssignale des Detektors aus Fig. 5;

Fig. 7 -

eine grafische Darstellung der Zeitabhängigkeit der Drehzahl eines Antriebsmotors während des Betriebs einer Sitzverstelleinrichtung.

Show it:

Fig. 1 -

a signal generator and an associated detector for executing the method according to the invention;

Figures 2 to 4 -

Various characteristic curves of motor-driven adjustment devices of motor vehicles, on the basis of which the tolerance-related characteristic properties of the partitions of a signal transmitter according to FIG. 1 can be determined;

Fig. 5 -

a second embodiment of a signal generator and an associated detector for performing the method according to the invention;

Fig. 6 -

a representation of the output signals of the detector of Fig. 5;

Fig. 7 -

a graphic representation of the time dependence of the speed of a drive motor during the operation of a seat adjustment device.

In Fig. 1, a signal generator 1 is shown in the form of a multi-pole, circular magnetic disc which is arranged on the drive shaft 10 of a rotating drive of an adjusting device in a motor vehicle and which has a total of six adjacent partitions 11 to 16 in the form of circular segments, each circular segment 11 to 16 a manic north pole N ₁ , N ₂ , N ₃ or a magnetic south pole S ₁ , S ₂ , S _{3 is} assigned. Compared to this signal transmitter 1, a Hall sensor 2 is arranged as a detector, which generates in a known manner, based on the magnetic signal generated by the signal transmitter 1, an output signal U ₁ representing the rotary movement of the drive shaft 10, which is generated by an electronics unit (not shown in FIG. 1) the adjustment device is fed for evaluation. The position, the speed and the acceleration of the drive shaft 10 can be determined in a known manner by means of the electronics unit.

When using a second Hall sensor 3, which is arranged as part of the detector next to the first Hall sensor 2 according to FIG. 5 and which generates a second output signal U ₂ , the direction of rotation of the drive shaft 10 can also be determined in a simple manner. However, methods for determining the direction of rotation using only one sensor are also known.

Such signal transmitters and associated sensors for determination the position, speed, direction of rotation and acceleration a drive motor are known and therefore need not to be described in more detail.

With such a device, inaccuracies in the determination of the speed, acceleration etc. on the one hand occur in that the expansion of the individual circle segments 11 to 16 along the circumference of the signal generator 1 (Angular expansion) is subject to production-related fluctuations, i.e. the actual angular extent of each Circular segments deviate from the ideal (theoretical) angular extent from. Furthermore, the digitization of the Signals that occur at the transitions between each North and South Poland is generated, further inaccuracies occur; in particular point north-south transitions in the Usually a slightly different characteristic than south-north transitions. In addition, there may be further measurement errors, the due to tolerances of Hall sensor 2 or 3 are tolerances of the hysteresis of the switching thresholds of Hall sensors.

The tolerance-related characteristic properties of the partitions 11 to 16 of the signal generator 1 and the transitions between the individual partitions 11 to 16 (and possibly the detector 2 or 3) are preferably determined after each start of the drive of the seat adjustment device. On the basis of this, a correction value is determined for each partition 11 to 16 of the signal generator 1 and linked to the output signals U ₁ , U _{2 of} the Hall sensors 2 and 3, respectively. These correction values are assigned to partitions 11 to 16 and stored accordingly. When the drive or motor continues to operate, each time the speed is measured by means of the signal transmitter 1 and the Hall sensors 2, 3, the respective measured value is linked to the associated stored correction value, as a result of which the tolerance-related measurement errors are considerably reduced.

A test movement of the signal generator to determine the tolerance-related characteristic properties of the signaling partitions as part of an electronic error correction can with a rotating drive that according to FIG 1 connected to a circular disk-shaped signal generator 1 is in one or more revolutions of the drive and signal generator 1 for detecting the individual sectors or circle segments 11 to 16, with a longitudinally adjustable Signalers in the travel of a straight line or predetermined curved route to capture the individual Route subdivisions or the like exist.

The test movement preferably consists of a predetermined one Movement section of the signal generator with essentially constant acceleration and / or constant speed, so that due to defined drive conditions, for example, by recording the time between successive ones Signals, their relationship to a movement period, for example one revolution, and thus whose share in the period can be determined, from which to a concrete value, for example an angle that individual partitions can be closed.

The tolerance-related characteristic properties of the Signal generator partitions 11 to 16 according to FIG. 1 preferably determined after each start of the drive. is however, ensures that it is an intrinsic system acts (i.e. when securing a permanently unique Assignment between signaling partitions and sensor signals), so the tolerance-related characteristic properties the signaling partitions 11 to 16 once can be recorded and saved and thus permanent error correction guarantee.

Alternatively, the tolerance-related characteristic Properties of auto switch partitions 11 through 16 be adaptively adapted in predetermined test cycles, the means after an initial determination of the tolerance-related characteristic properties of the signaling partitions 11 to 16 becomes after a predetermined number of operating cycles a test cycle is provided, its correction values replace the original correction values or for example adjust by averaging.

The electronic error correction provides, in particular, for a correction value to be determined for each signal transmitter partition 11 to 16 and to be linked with the sensor signals U ₁ . In this case, a correction value for each individual partition or each individual sector 11 to 16 of the signal generator is determined in a measurement cycle and assigned to this partition 11 to 16. When the drive or motor is in operation, the measurement value is linked to the stored correction value, that is to say, for example, multiplied, added, divided or subtracted, for each measurement of the speed with a signal generator partition 11 to 16. As a result, the measurement error, which is connected to the individual signal transmitter partitions 11 to 16, is greatly reduced. The accuracy of the measured value then only depends on the processing range of the numbers in the calculation method for determining the speed or acceleration.

With circular disk-shaped, rotating signal transmitters 1 with Partitions 11 to 16 in the form of circular segments can be in simple, immediately corrected angle of rotation of the partitions 11 to 16 can be determined that the actual Extension of the individual signaling partitions 11 to 16 correspond on the ring magnet.

For the actual, corrected angular expansion α _{i of} the i-th partition of a signal transmitter (extension of the corresponding partition along the circumference of the signal transmitter), assuming a rotary movement with essentially constant acceleration α i = Ω * dT i + (Ω '/ 2) * (dT i ) 2 . where Ω is the angular velocity of the rotary motion and Ω 'is its derivative over time (angular acceleration). dT _i represents the time interval required for the signal transmitter to be rotated by the angle which corresponds to the actual angular extent of the i-th signal transmitter partition under consideration. With known acceleration of the drive (and thus known speed at any time), the actual angular expansion α _{i of} the individual signaling partitions can be determined in real time from this by measuring the corresponding time intervals dT _i .

The practical implementation is described below using the determination of the angular extent α _{5 of} the fifth signal generator partition of one in eight adjacent partitions P1, P2, P3, P4, P5, P6, P7, P8 in the form of circle segments (the eighth partition P8 in turn being connected to the first Partition P1 borders) divided circular disk-shaped signal generator explained. For this purpose, assuming a constant acceleration of the drive: Ω '= (Ω end - Ω anf ) / Dt 5 . in which Ω anf = 2 * π / T anf and Ω end = 2 * π / T end and
where T _beginn and T _end respectively represent the time duration of a complete revolution of the signal generator starting at the first signal generator partition and the second signal generator partition, which are offset from one another by the time interval dT ₁ . Accordingly, T _{beginn represents} the duration of a (first) complete revolution of the signal generator, in which first the first, then the second, third, fourth, fifth, sixth, seventh and finally the eighth signal generator partition pass the assigned sensor, i.e. in the order P1 , P2, P3, P4, P5, P6, P7, P8. T _end represents the duration of a complete revolution of the signal generator, which is shifted by the time interval dT ₁ compared to the first rotation, so that first the second, then the third, fourth, fifth, sixth, seventh, eighth and finally the first signal generator partition assigned sensor, so in the order P2, P3, P4, P5, P6, P7, P8, P1.

In other words T anf = Σ 1 8th dT i and T end = Σ 2 9 dT i = T anf - dT 1 + dT 9 . where dT _{9 represents} the time interval during which the first signal generator partition P1 passes the assigned sensor again immediately after a (first) complete revolution of the signal generator. That is, T _end can be determined from T _beginn by subtracting the contribution dT ₁ , which originates from the first partition P1 of the signal generator during said first rotation, from T _beginn (which represents the period of the first complete revolution of the signal generator), and instead, the time interval dT _{9 is} added, during which the first partition P1 passes the signal generator in the immediately following (second) revolution.

The term "first complete revolution" of the signal generator should not suggest that it is first turn at all (after commissioning the Drive). It's all about one Ranking of the individual successive revolutions establish by making a certain revolution first complete revolution is referred to; the further turns are then called the second turn, third turn etc.

From the above approach, the fifth signal transmitter partition results for the actual angular expansion ₅ α 5 = Ω anf * dT 5 + (Ω end - Ω anf ) / (2 * dT 5 ) * (DT 5 ) 2 . and from this follows by performing the addition: α 5 = 0.5 * (Ω end + Ω anf ) * DT 5 ,

These formulas can be used to determine the angular extent α _{i of} all partitions of the signal transmitter by numbering the eight partitions (circle segments) arranged side by side on a circular disk such that the partition to be examined forms the fifth partition.

Thus, the corrected (actual) angular expansion α _i of any partition of the signal generator can be determined by first measuring the time intervals during which the individual partitions pass the assigned sensor during a (first) revolution of the signal generator, and T _{beginning is} determined therefrom , The time interval during which the first partition of the signal generator passes the sensor during the immediately following (second) rotation is then measured. This leads to the _anf with the above equations to calculate T _end using T. The correct (actual) angular _{extent of} the corresponding partition of the signal generator finally results from T _beginn and T _end .

It should be noted that with the above formulas none real correction values are determined, which are still with the ideal (theoretical) angular expansion of the individual signal generator partitions must be linked to their actual Get angular expansion. Rather be immediate the actual, corrected values for the Angular expansion of the signaling partitions determined. From this can, for example, be an additive or a Determine the multiplicative correction value in that the Difference or the quotient of the actual angular expansion and the ideal (theoretical) angular expansion be formed.

The termination criterion for ending the determination of the characteristic properties of the Auto switch partition is met when the correction values or corrected auto switch partitions in at least two consecutive cycles within one predetermined tolerance range and / or the sum the correction values or corrected partitions within one cycle (apart from tolerable deviations) is equal to the value of a period of the signal generator.

In the first case design, there are at least two consecutive ones Cycles, i.e. complete turns of the Drive shaft required to compare the correction values to be able to make and determine whether any Deviations in the correction values for the individual partitions or sectors within a specified tolerance range lie. If this is not the case, there are more Test cycles required.

The second case is just a test cycle, i.e. one revolution of the drive shaft (apart from the possible need after completing this turn even more zeint intervals to determine the angular extent of the individual partitions) required if the sum of the corrected or normalized Sensor signals for example at an angle of 360 ° a full revolution of the circular disk-shaped signal transmitter equivalent. Other control procedures are of course also possible possible, for example in such a way that the sum of all correction factors corresponds to a predetermined value. There is only one revolution for this termination criterion the drive shaft is required in the event of an uneven However, this accelerates the drive causes measurement errors. For this reason, this criterion only applied in uniform movement sections, that can be determined empirically.

Another variant for determining the termination criterion for the correction procedure is a sliding Averaging or a combination of the two Variants presented above, i.e. in every test cycle must be the sum of the correction values or corrected Auto switch partitions within a cycle equal to that Value of a period of the signal generator and the correction values or corrected signaling partitions in succession Cycles must be within a specified tolerance range lie.

After the fulfillment of the termination criterion is determined the algorithm uses the correction values to calculate the exact speed values for the corresponding signal generator partitions, i.e. in the case of a circular signal transmitter the exact speed values for the individual sectors.

In Figures 2 to 4 different options are Determination of the tolerance-related characteristic properties the signaling partitions and the following Comparison with the sensor signals based on characteristic curves a motor-driven adjustment device in motor vehicles as speed or speed above the Time t shown. These representations are intended to clarify that the test movement in particular part or part the operating run of a motor-driven adjustment device can be, especially if the test move after each start of the drive to determine the tolerance-related characteristic properties of the signaling partitions is carried out.

FIG. 2 shows in a speed-time diagram the time course of a constantly accelerated adjusting device, in which the tolerance-related characteristic properties of the signal transmitter partitions are determined in the time period between t ₁ and t ₂ , while in a subsequent time section t ₄ to t _{5 of the} same A comparison with the sensor output signals is carried out during the course of the adjustment device or its drive.

Figure 3 shows in a speed-time diagram the time course of a motor-driven adjusting device moving at constant speed, in which the tolerance-related characteristic properties of the signaling partitions are also determined in the time period between t ₁ and t ₂ , while in the time period between t ₄ and t ₅ a corresponding comparison is made.

Figure 4 is a temporal representation of the speed of a motor-driven adjusting device which is moved further up to the time t ₃ with constant acceleration until reaching the rated rotational speed n _rated or nominal speed is accelerated and then at a constant speed or constant nominal speed becomes. In this embodiment, the tolerance-related characteristic properties of the signal transmitter partitions are determined in the period between t ₁ and t ₂ during startup, ie constant acceleration of the motor-driven adjustment device, during the adjustment in the period between t ₄ and t ₅ after the nominal speed has been reached he follows.

A circuit-technical variant of the method according to FIG. 5 requires two sensors 2, 3 assigned to the six-pole signal transmitter 1 and spaced apart along the movement path of the signal transmitter. Due to manufacturing-related inaccuracies, the six sectors of the six-pole magnet are not of the same size and may not be magnetized to the same extent, so that at a rotation of the magnetic disc 1 with constant speed or constant acceleration, the Hall sensors 2, 3 detect different measuring times for the individual sectors. In order to remedy this problem, the rising and / or falling edges of the sensor signals U ₁ , U _{2 of} the two sensors 2, 3 triggered by the partitioning of the signal generator 1 are recorded and the time difference between signals of the sensor signals U ₁ , U ₂ assigned to the same partition of the signal generator 1 determined and evaluated to determine the tolerance-related characteristic properties of the signal generator partitions 11 to 16.

The speed of the signal generator 1 is thus determined by that the time interval is measured in which a certain point of the signal generator 1, namely an N-S or an S-N transition in succession the two sensors 2, 3 happens. By the angular distance between the two sensors 2, 3 (ie the distance between the two sensors 2, 3 along the Scope of the signal generator 1) by the time measured in this way divided, you get the speed of the signal generator and thus the drive.

The detection of the time difference between the increasing or falling edges of the two sensor output signals eliminates different lengths of auto switch partitions or different angular sections of the signal generator sectors and thus eliminates manufacturing inaccuracies of the Auto switch.

Basically, the distance a between the two sensors any along the path of the signal generator 1 be, for example in a circular disk-shaped signal generator form an angle of 90 ° between sensors 2, 3, however, fall at a distance greater than the extent of the smallest partition or a multiple of which is speed or acceleration changes of the signal generator 1 is more important, so that the limits the measurement accuracy is lower. For this reason are the sensors 2, 3 for a current speed determination from the individual signaling partitions instead averaging at a distance a from one another arranged, which is preferably less than or equal to the smallest Partition of the signal generator 1 is.

Figure 6 shows the sensor output signals of the embodiment from Figure 5 and illustrates the different long time intervals between the rising and falling Flanks of, for example, the unequal Sectors 11 and 12 of the magnetic disk 1 triggered signals. the time difference T between the increasing or falling edges of the sensor output signals of the two Hall sensors 1, 2 determined, so are the by unequal The lengths of the individual sectors differed Pulse lengths when capturing the individual sectors eliminated.

Is the distance a between the two along the periphery the magnetic disk 1 offset from one another Hall sensors 11, 12 smaller than the smallest magnetic disk sector, the greatest measurement accuracy results, as possible Changes in speed or acceleration in this period don't matter. At larger distances between the two Hall sensors at speed or Acceleration changes averaging and thus an increase in measurement inaccuracy.

It is now with reference to Figures 1 and 5 (which is only with regard to the number of assigned to the signal generator Differ sensors) in connection with Figure 7 die Regulation provided according to a second aspect of the invention a motor-driven adjustment device immediately after switching on the engine and under Taking into account the simultaneous determination of correction values explained.

Regarding the determination of the correction values, here is again mentioned that the correction values are preferred can be determined recursively, with the termination criterion for The determination of the correction values is then completed is when the correction values are in at least two consecutive Cycles within a specified tolerance range lie and / or the sum of the corrected partitions of the signal generator 1 during a cycle within a predetermined Tolerance range around the value of a period of the Signal generator 1 is (i.e. the sum of the angular dimensions of the individual segments of the magnetic disc except for permissible Deviations is equal to 360 °).

By summarizing this in more detail above described method for determining the correction values it becomes particularly clear that intermediate results are constantly being achieved are formed on the basis of which they are continuously checked becomes whether the termination criterion regarding the determination the correction values are fulfilled. The peculiarity of the present Procedure for regulating an adjusting device for motor vehicles, and in particular a seat adjustment device, lies in the fact that these interim results included in the control of the drive of the adjusting device become. This will be explained in more detail below with reference to FIG. 7 are explained.

7, the speed n of the drive motor of a seat adjustment device for motor vehicles is plotted against the time t. In this diagram, n _{AP also designate} the target speed of the motor at its working point and tAp the point in time until which the motor is to be started up to its target speed.

The line labeled S in the diagram according to FIG. 7 shows the target engine speed at every point in time t a defined movement of the seat adjustment device.

In a first time period (up to time t _AP ), the motor is to be started up with a constant acceleration (on a "ramp") up to its target speed at the operating point. The actual adjustment movement should then be carried out at a constant speed. The motor is then shut down again with a constant negative slope, i.e. along a descending ramp.

The task now is to determine the actual speed, which in the diagram of FIG. 7 by the designated T Line is represented to regulate such that the Deviations of the actual speed from the target speed are as low as possible.

For this purpose it is provided according to the invention that on the one hand after operating the motor, tolerance-related characteristic Values of the signal generator are determined and correction values from them be determined when evaluating the output signals be taken into account and at least as long be adjusted until a predetermined termination criterion is fulfilled, and that on the other hand already during the Determination and adjustment of the correction values for intermediate results of these values for determining controller parameters of the Control algorithm can be used. Because of the latter Measure can already start controlling the speed, before the correction values were determined with sufficient accuracy. In particular (as soon as the first interim results of the Correction values were determined) already when starting the Motors along the rising ramp a regulation of the Speed take place. This will preferably be comparative "soft" controller parameters used, the larger Allow the speed to fluctuate around the setpoint. After reaching the engine working point and after The termination criterion will then be met accordingly "Harder" controller parameters are used to control the speed, so that the speed then only slightly the target speed may deviate.

In addition, immediately after starting the drive still be provided that the determination of the speed by means of the signal generator and the associated detectors and by means of those programmed with the control algorithm Electronic unit through a moving averaging over several representing the speed of the drive motor Signals. This will increase the accuracy of the Determination of the speed increased, but at the expense of Real-time content of the speed information. Once the correction values have been determined with sufficient accuracy the averaging can therefore be abandoned.

It should also be mentioned that those determined by this method Correction values of the controller parameters also when shutting down of the drive at the end of the adjustment movement can be.

With regard to further details and possible variants when regulating the drive on the relevant For explanations refer to the introduction to the description. These can be easily referred to in FIGS. 1, 5 and 7 embodiment shown.

Claims (30)

1. Method for regulating motor driven displacement devices in motor vehicles wherein

   a) a partitioned signal transmitter (1) coupled to the motor generates a signal representing the speed of the motor,

   b) a detector (2, 3) dedicated to the signal transmitter detects this signal and generates a corresponding output signal and

   c) a regulating unit evaluates the output signal and adjusts the speed of the motor in dependence on the output signal,

   characterised in that
   the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) are determined in the start-up phase of the motor and are taken into consideration during evaluation of the output signals (U₁, U₂).
2. Method for regulating motor driven displacement devices in motor vehicles according to claim 1 in which a partitioned signal transmitter coupled to the motor generates a signal representing the speed of the motor, a detector dedicated to the signal transmitter detects this signal and generates a corresponding output signal and a regulating unit evaluates the output signal and adjusts the speed of the motor in dependence on the output signal wherein the angular extensions (αi) of the signal transmitter partitions (11 to 16) are determined as the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) and taken into account when evaluating the output signals (U₁,U₂).
3. Method according to claim 1 or 2 characterised in that an actual corrected angular extension αi of the i-th signal transmitter partition is determined according to: αi= Ω * dTi + (Ω'/2) * (dTi)2 in which Ω represents the angular speed of the rotational movement of the motor and Ω' represents its derivative according to the time, thus its angular acceleration and dTi represents the time interval which is required for a rotation of the signal transmitter about the angle αi.
4. Method according to one of claims 1 to 3 characterised in that the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) are determined in a test movement of the signal transmitter (1).
5. Method according to claim 2, 3 or 4 characterised in that the test movement consists of a predetermined movement section of the signal transmitter (1) with substantially constant acceleration and/or constant speed.
6. Method according to one of the preceding claims characterised in that after determining the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) in a test movement of the signal transmitter (1) a balancing of the output signals (U₁, U₂) is undertaken in the same run of the displacement device or its drive.
7. Method according to one of the preceding claims characterised in that the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) are determined after each start-up of the drive.
8. Method according to one of claims 1 to 7 characterised in that the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) are determined and stored once.
9. Method according to claim 8 characterised in that the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) are tuned adaptively in predetermined test cycles.
10. Method according to one of the preceding claims characterised in that the individual correction values are determined in that the sum of the times of the individual signal transmitter partitions (11 to 16) is measured during a test cycle and in a subsequent measuring process the time of the first signal transmitter partition (11) is still measured during the immediately following test cycle.
11. Method according to one of the preceding claims characterised in that determining the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16) is concluded when the correction values or corrected signal transmitter partitions (11 to 16) in at least two successive cycles lie within a predetermined tolerance range and/or the sum of the correction values or corrected signal transmitter partitions (11 to 16) within one cycle is equal to the value of one period of the signal transmitter (1).
12. Method according to claim 1 with two detectors assigned to the signal transmitter characterised in that the time differences between the rising and/or falling flanks of the output signals (U₁, U₂) of the two detectors (2, 3) are measured in one test movement of the signal transmitter (1) and are evaluated in order to determine the tolerance-conditioned characteristic properties of the signal transmitter partitions (11 to 16).
13. Method according to claim 12 characterised in that the detectors (2, 3) are mounted along the path of movement of the signal transmitter (1) at a constant spacing from each other which is less than or equal to the smallest signal transmitter partition (11 to 16).
14. Method for regulating motor driven displacement devices in motor vehicles in which

    a) a signal transmitter (1) coupled to the motor generates a signal representing the speed of the motor,

    b) a detector (2, 3) dedicated to the signal transmitter detects this signal and produces a corresponding output signal and

    c) a control unit provided with a control algorithm evaluates the output signal and adjusts the speed of the motor in dependence on the output signal,
    more particularly according to one of the preceding claims,
    characterised in that

    d) after actuating the motor tolerance-conditioned characteristic values of the signal transmitter (1) are determined and from this correction values are determined which are taken into account when evaluating the output signals (U₁, U₂),

    e) the correction values are adapted at least so long as a predetermined disconnection criterion is not met; and

    f) during determining and adapting the correction values intermediate results of these values are formed and used for fixing the regulator parameters of the regulating algorithm.
15. Method according to claim 14 characterised in that the adaptation of the correction values is continued even after reaching the operating point of the motor so long as the disconnection criterion is not met.
16. Method according to claim 15 characterised in that the adaptation of the correction values is continued without restriction after reaching the operating point of the motor.
17. Method according to one of claims 14 to 16 characterised in that after reaching the operating point of the motor the regulator parameters are newly fixed again.
18. Method according to claim 17 characterised in that the regulator parameters are fixed anew as soon as the operating point of the motor is reached and the adaptation of the correction values has been completed.
19. Method according to one of the preceding claims characterised in that after triggering the motor its ideal speed (U_soll) is raised with a substantially constant acceleration.
20. Method according to one of the preceding claims characterised in that after triggering the motor in order to determine its speed (n) at first an average is formed through several output signals (U₁, U₂) representing the speed (n) of the motor.
21. Method according to claim 20 characterised in that determining the speed (n) is carried out through a sliding mean value formation.
22. Method according to one of claims 14 to 21 characterised in that the signal transmitter (1) has a partitioning (11-16) and that the correction values serve to compensate tolerances which are due to the partitioning (11 to 16).
23. Method according to one of claims 1 to 13 or claim 22 characterised in that for each partition (11 to 16) of the signal transmitter (1) a correction value is determined and linked to the output signals (U₁, U₂).
24. Method according to claim 23 characterised in that the signal transmitter (1) rotates during operation of the motor and that for each partition (11 to 16) a corrected rotational angle is determined which represents the actual extension of the partition (11 to 16) along the circumference of the signal transmitter (1).
25. Method according to one of the preceding claims characterised in that the signal transmitter (1) generates the signals according to a magnetic, inductive, capacitative, resistive or optical principle.
26. Method according to one of the preceding claims characterised in that the signal transmitter (1) is formed as a multi-pole magnet.
27. Method according to claim 26 characterised in that the signal transmitter (1) is formed as a multi-pole magnetic disc which rotates during operation of the motor.
28. Method according to one of claims 1 to 25 characterised in that the signal transmitter is a constituent part of the electromechanical system of the motor.
29. Method according to one of claims 14 to 21 characterised in that the motor current serves as signal transmitter.
30. Method according to one of the preceding claims characterised in that it serves to regulate seat adjusters in motor vehicles.

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