Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P1/00—Arrangements for starting electric motors or dynamo-electric converters
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
  • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
  • H02H7/08—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors
  • H02H7/085—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors against excessive load
  • H02H7/0851—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors against excessive load for motors actuating a movable member between two end positions, e.g. detecting an end position or obstruction by overload signal
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
  • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
  • H02H3/006—Calibration or setting of parameters
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
  • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
  • H02H7/08—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors
  • H02H7/093—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors against increase beyond, or decrease below, a predetermined level of rotational speed

Definitions

• the invention relates to a method for adjusting a vehicle part between at least two positions according to the preamble of claim 1 and a drive device for a vehicle part adjustable between at least two positions according to the preamble of claim 13.
• a drive device for a motor vehicle window which detects the motor speed by means of two Hall detectors and reverses the motor when a threshold value for the relative change in speed is exceeded.
• the threshold value is constantly recalculated as a function of the detected motor voltage and the ambient temperature determined by a temperature sensor on the motor. The standstill / operating times of the motor are also taken into account in order to be able to infer the ambient temperature from the motor temperature.
• a disadvantage of these generic speed detection systems is that due to the individual fluctuations in the characteristic curves of the motors used, the assignment of the measured motor speed to the corresponding motor torque, i.e. the corresponding action of force on the adjustable vehicle part is subject to these random fluctuations, which results in inaccuracies in the detection of a trapping event.
• the time at which each pulse signal is input to the control unit is recorded, a value for the change in engine speed is determined from at least some of these previously measured times, and a force change value is calculated from each speed change value by multiplication by a proportionality factor. which is used in determining the value for the momentary force acting on the moving vehicle part.
• This proportionality factor is preferably selected as a function of the engine characteristic.
• the motor characteristic curve is preferably determined for at least one motor voltage without a driven vehicle part, with two fixed value pairs of speed and torque preferably being measured for a fixed motor voltage.
• the proportionality factor is preferably also selected as a function of the engine temperature, the engine temperature preferably being estimated by detecting the ambient temperature and the operating time of the engine.
• FIG. 1 shows a schematic illustration of a drive device according to the invention
• FIG. 2 shows a graphical representation of an exemplary temporal course of the period of the motor rotation
• FIG. 3 shows a schematic representation of an embodiment of the method according to the invention for determining a trapping situation
• FlG. 4 schematically shows a vehicle roof to illustrate the method according to FIG. 3.
• a magnetic wheel 18 with at least one south and one north pole is mounted on the shaft 12 in a rotationally fixed manner.
• several, for example four, north and south poles can also be arranged on the magnetic wheel 18, which shortens the period of the signals accordingly.
• Two Hall sensors 20, 22 are arranged near the magnetic wheel 18 in the circumferential direction, each of which sends a pulse signal to a control unit 24 provided with a microprocessor 36 and a memory 38 each time the north or south pole of the magnetic wheel 18 passes emit, which thus receives a signal about every quarter turn of the shaft 12.
• the period duration results in each case from the distance between two successive signals on the same sensor 20 or 22, which are received at a distance of one full rotation of the shaft 12.
• the period is alternately calculated from the time difference of the last two signals on the sensors 20 and 22, so that a new value of the period is available every quarter of a turn.
• the direction of rotation can also be determined on the basis of the phase shift of the signals of the two sensors 20, 22.
• the current position of the cover 54 can also be determined from the signals of the Hall sensors 20, 22 by feeding these signals to a counter 40 assigned to the control unit 24.
• the direction of rotation of the electric motor 10 can be controlled by the control unit 24 via two relays 26, 28 with changeover contacts 30, 32.
• the speed of the motor 10 will be controlled by pulse width modulation via a transistor 34 controlled by the control unit 24.
• the microprocessor 36 determines the monthly period of the rotation of the shaft 12 and thus also of the electric motor 10. Thus, a measurement value for the period is available approximately every quarter of a revolution of the shaft 12. In order to guarantee protection against trapping between these times, a fixed time grid, e.g. after every 1 ms, estimates for the period are extrapolated from previous measured values of the period, for example using the following formula:
• T * [k] T [i] + k • (al • T [i-1] + a2 • T [i-2] + a3 ⁇ T [i-3]) (1)
• al, a2, a3 are parameters, i is an index that every quarter, incremented, and k is the running index of the fixed time grid, which is reset to zero for each new measurement for the period.
• i is an index that every quarter, incremented
• k is the running index of the fixed time grid, which is reset to zero for each new measurement for the period.
• the parameters al, a2, a3 model the overall system of the drive device, ie motor 10, power transmission components and cover, and are determined by the spring stiffness, damping and friction of the overall system. This results in a bandpass effect with the property that spectral components of the period over time, that of Vibrations originate, are rated weaker than those resulting from a trapping event.
• FlG. 2 schematically shows an exemplary temporal course of the measured period durations T and the period durations T * estimated therefrom. The dashed curve represents the true course of the period.
• the speed change at time [k], based on the previous time [k-1], is then estimated from the estimated values for the period, using a motor voltage filter and a travel profile filter to determine the influences of the motor voltage and the position at which the moving vehicle part, ie the cover, just located, to eliminate the engine speed using the following formula:
• Um [k] is the motor voltage at the time [k]
• Vu is a motor voltage filter which simulates the dependence of the speed on the motor voltage detected by the control unit 24
• x [k] is the position of the cover at the time [k]
• Vr is a displacement profile filter that simulates the dependence of the engine speed on the position of the cover.
• the motor voltage filter Vu simulates the dynamic behavior of the motor when the voltage changes.
• the motor voltage filter Vu is preferably designed as a low-pass filter, the time constant of which is equal to the motor time constant.
• the time constant depends on the operating case, i.e. the opening or closing of the cover 54 in the sliding or lowering direction, and the magnitude of the change in voltage.
• the path profile filter Vr is automatically determined by a learning run after installation of the drive device in the vehicle. It is also possible to adapt to changed operating conditions - e.g. due to wear - at certain intervals during the life of the system. Instead of a single learning run, statistical averages determined from several (for example 50) learning runs can also be used for data acquisition for the path profile filter. As mentioned above, the position of the cover 54 is determined from the pulse signals of the Hall sensors 20, 22 which are summed up by means of the counter 40. The decision as to whether or not there is a jamming is made using the following formula:
• the estimated speed changes ⁇ N * [k] are compared with a fixed lower limit that is constant over time. As soon as they exceed this lower limit, they are each multiplied by a proportionality factor Vf, which represents the steepness of the motor characteristic of the electric motor 10 (torque versus speed). The slope is approximately constant at constant motor voltage and motor temperature, but is different for each electric motor 10.
• Vf proportionality factor
• the ambient temperature is detected by a temperature sensor and the motor temperature is approximated by recording the operating time (instead of the ambient temperature, the motor temperature can also be detected directly by a temperature sensor on the electric motor 10).
• the ⁇ F [k] values are added up as long as the ⁇ N * [k] values are above the specified lower limit. As soon as two consecutive ⁇ N * [k] values are below it again, the sum is set to zero. If a ⁇ N * [k] value exceeds a fixed upper limit, only the value of the upper limit is included in the sum instead of this ⁇ N * [k]. This serves to eliminate as far as possible the effects of vibrations, which lead to brief, periodic peaks in the speed change, on the detection of a trapping event. In the simplest case, this upper limit can be chosen to be constant. In order to increase the accuracy of the triggering, the upper limit can also be dependent on the current determined speed change can be selected to be variable in time, for example in such a way that the upper limit is raised with increasing current speed change.
• the control unit 24 triggers a reversal of the electric motor 10 by actuating the relays 26, 28 via the switches 30, 32 in order to immediately release a jammed object or a jammed body part to give.
• the trapping protection is active by the described extrapolation of the period also between two measured values of the period at fixed times, whereby a trapping event can be detected earlier, ie even with fewer cycles, which better prevents injuries or damage and thereby the safety of the drive devices ⁇ go increased.
• a spectral analysis of the speed changes determined within a certain time window up to the time of analysis can be carried out. If certain spectral characteristics occur, in particular if a clearly pronounced peak occurs, which is not in the spectral range typical for pinching cases, triggering is prevented, even if the threshold Fmax is exceeded.
• FIG. 3 schematically shows a second embodiment of the invention.
• the essential difference from the first embodiment described above is that, in a first calculation 50, a second calculation 52 with its own parameter set is carried out in a first calculation 50 in parallel and independently of an inventive extrapolation of the measured period durations at specific times and the determination of estimated values for the force acting on the adjustable vehicle part and another sampling rate is carried out, which also provides a value for the current force.
• the results of both calculations are taken into account when deciding whether the engine should be switched off or reversed. This follows from the following considerations:
• the rigidity of the overall system is made up of the rigidity of the sliding-lifting roof mechanism, the clamped body and the vehicle body.
• the stiffness of the pinched body depends on the type of body.
• the rigidity of the body is heavily dependent on the place where the body is pinched. This applies in particular to the lowering movement of a cover 54 from an opening position, see FIG. 4. If a body 56 is clamped in the area of the roof center (indicated in FIG. 4 with 58), the overall system is considerably softer due to the possible deflection of the rear edge of the cover than when pinching in the edge area (indicated in Fig. 4 with 60).
• the sampling rate means the distance between the times at which a value for the momentary force is determined. If the system works with a single fixed sampling rate, the parameter set of the calculation, in particular the threshold or limit values, and the selected sampling rate can only be optimized for a single stiffness of the overall system, although in practice depending on the type and location of the pinched Body different stiffnesses of the overall system can be decisive.
• the second calculation 52 is preferably for the detection of slow changes in force, i.e. small stiffnesses optimized, while the first calculation 50 for the detection of rapid changes in force, i.e. great stiffness is optimized.
• the second calculation 52 does not require extrapolation of measured values of the period, but, depending on the relevant stiffness range, at most after a new measured value has been received or only after every nth input of a measured value a new value of the momentary force applied. In principle, however, the second can, if necessary Calculation 52 use an extrapolation algorithm, the extrapolation times being selected at a greater distance than in the first calculation 50.
• the engine temperature is taken into account when determining the speed when converting speed change into force change according to formula (3).
• the first sampling rate is selected so that it is optimal for the detection of pinching cases with the highest system stiffness to be expected
• the speed detection stage 62 is used jointly by the first calculation 50 and the second calculation 52.
• the speed change .DELTA.N * using the formula (3) in the manner described above using a first value for the fixed lower limit, a first value for the fixed upper limit and a first value for the threshold value Fmax becomes the first sampling rate specified times, ie the extrapolation times [k], ascertained whether the momentary force effect exceeds this first threshold value Fmax.
• the values of this first parameter set are optimized for the detection of pinching cases with the greatest expected system rigidity.
• the sampling rate is selected so that it is optimal for the detection of pinching cases with the lowest expected system stiffness.
• This second sampling rate can be chosen, for example, so that only every fourth measured value of the period T is to be taken into account.
• the second calculation is carried out only at every fourth signal input by the Hall sensors 20, 22, ie only every fourth speed N [i] determined by the stage 62, which is based on a measured period T in the period shown in FIG 4 takes into account the sampling stage indicated by 66 (indicated by 66 in FIG. 4), which goes back to a measured period T.
• the extrapolated from Periods T * determined speeds N * [k] are of course not taken into account anyway.
• the second calculation 52 is therefore only carried out every fourth point in time [i].
• the speed change ⁇ N [i] compared to the last measured value is determined. Then it is determined in an analogous manner by means of the formula (3) using a second value for the fixed lower limit, a second value for the fixed upper limit and a second value for the threshold value Fmax, whether the momentary force action exceeds this second threshold value Fmax.
• the values of this second parameter set are optimized for the detection of pinching cases with the lowest expected system rigidity.
• the results of the first and the second calculation are logically linked to one another in a logic stage 64.
• this is an OR operation.
• the motor is switched off or reversed when one of the two calculations has detected a case of jamming.
• the decision is made at any point in time at which the first calculation 50 delivers a new result. Since new results of the second calculation 52 are available much less frequently, the last result of the second calculation 52 is always supplied to the logic stage 64.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Power-Operated Mechanisms For Wings (AREA)
• Control Of Electric Motors In General (AREA)
• Control Of Direct Current Motors (AREA)

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• 1998
  • 1998-09-03 DE DE19840161A patent/DE19840161A1/de not_active Ceased
• 1999
  • 1999-09-03 JP JP2000569482A patent/JP2002525016A/ja active Pending
  • 1999-09-03 EP EP99946120A patent/EP1110290A1/de not_active Withdrawn
  • 1999-09-03 KR KR1020017002847A patent/KR100738859B1/ko not_active IP Right Cessation
  • 1999-09-03 WO PCT/EP1999/006510 patent/WO2000014845A1/de active Application Filing
  • 1999-09-03 US US09/786,392 patent/US6597139B1/en not_active Expired - Fee Related

Non-Patent Citations (1)

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