DE3021501A1 - METHOD AND DEVICE FOR CONTROLLING A POSITIONING DRIVE, ESPECIALLY FOR TRANSPORT CABINS - Google Patents

Description

fo / kr

M.A.N. Maschinenfabrik Augsburg-Nürnberg Aktiengesellschaft

Nuremberg, June 2, 1980

Method and device for regulating a positioning drive, in particular for transport cabins

The invention relates to a method and a device for regulating a positioning drive, in particular for transport cabins, with the help of a setpoint generator.

With such regulated conveyor systems, the aim is to ensure that the path between start and destination is smooth and as smooth as possible short time, with acceleration, top speed and deceleration values resulting from the Drive or resulting from the operating conditions, cannot or may not be exceeded. Simultaneously the optimization of the travel time should be achieved with economically justifiable means. She is therefore allowed to Example does not lead to oversizing of the drive. In addition, the setting of the drive should be make the lowest possible demands on the personnel during commissioning and maintenance. Here comes the Setpoint generator for the speed curve is of particular importance.

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Known operating procedures and setpoint generators (see e.g. DE-PS 26 54 327) enable acceleration to be set, Top speed and deceleration. This device is operated in such a way that it adapts to the delay phase a time follows in which with a low, the so-called positioning speed, until it is reached of the breakpoint is driven. The transition from travel at top speed to deceleration is initiated, if the conveyed goods, e.g. a cabin for passenger transport, passes a mark on the route that is in a certain Distance from the breakpoint is attached. The shortest possible travel time is achieved when the delay is just completed when the positioning speed is reached, i.e. when practically no more travel with Positioning speed must be covered.

Such known devices have a significant disadvantage in that such an adjustment of the Delay leaves no leeway for any disturbance variables. This means that the drive must be designed so that even in the most unfavorable load case it can still precisely follow the target value, which leads to overdimensioning of the Drive leads. In practice, therefore, although this is not favorable, a certain distance is still required in Positioning speed covered in order to provide a safety margin to compensate for a possible temperature drift and aging of components. ·.

A further disadvantage is the case of short trips when the starting point is not as far as before the scheduled brand that '· when passing the mark, the Endge- - is speed achieved because the delay then is already far completed before the breakpoint, so a long one. Must be covered with the positioning speed. To this latter disadvantage too

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Various methods have become known to avoid the delay point in relation to the mark on the route to move. Already in DE-PS 26 54 327 and DE-PS 26 4l 983 indicates how a time can be calculated by which the start of the delay must be postponed for short trips. Despite these improvements, the first-mentioned disadvantages remain known facilities received undiminished, the device according to DE-PS 26 14 386 creates only one insufficient remedy for this. It is suggested there, within the distance between the mark and the stopping point to apply a further mark, which with optimal deceleration with a certain target speed would have to be driven through, with the observed deviation of the actual speed from the Setpoint speed is processed as a correction variable by the setpoint generator. However, this can lead to disturbances, that occur after passing the second mark can no longer be taken into account, and beyond that the correction is only correct for a certain speed profile between the first and second mark be. According to DE-PS 21 O2 583, this can result be remedied that still further marks are arranged in the delay line, with the help of a good management of the delay is possible even at any speed when passing the first mark, however This entails a considerable effort for the installation and retrieval of the brands, in particular if several stops are provided on the route, makes the process uneconomical.

Finally, it is still known from DE-PS 25 16 448, the beginning of the delay as a waypoint between start and

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To calculate the target, but it must be assumed that that the distance required for acceleration or deceleration is in a fixed ratio. But also here the occurrence of possible disturbance variables cannot be adequately taken into account.

-The invention assumes that for acceleration a maximum value is specified, which is derived e.g. from the adhesion between the wheel and the rail or the adhesion between Rope and sheave or when transporting people from a physiological point of view, but not it is guaranteed in any case that the drive can actually follow this acceleration at full load. It must also be taken into account that the set final speed is not reached with every load. Consequently, it cannot be assumed for the delay that when the one mark is passed, which should be sufficient for cost reasons, reproducible operating conditions prevail. So there is also none Calculation of the starting point of the delay from the operating conditions before the mark is reached is possible, especially since disturbance variables must also be expected in the course of the delay. The only requirement which is placed according to the invention on the conveyor system, is that the mark in the route is set at such a distance from the stopping point that the drive on the route even under the most unfavorable Conditions can decelerate from a speed that is at least equal to or greater than the maximum possible driving speed. It should also be taken into account that the brand does not apply in every case the distance is available, or that the starting point can lie between the mark and the stopping point.

Accordingly, it is the object of the invention that

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To avoid disadvantages of known positioning drive controls and a method and a device are available to provide that in an economically justifiable budget guarantee a high level of operational safety with an optimal conveying capacity.

In a method of the type mentioned at the outset, this is achieved in that at least the maximum travel speed and deceleration corresponding to the specified auxiliary signal reduced approximately proportionally to the distance traveled, compared with the fed back output signal of the setpoint generator and the output signal thereby is regulated down in accordance with the course of the auxiliary signal.

A setpoint generator is used to carry out the method, which is characterized by a device for generating an auxiliary signal H that is approximately proportional to the route, by a comparator device for comparing the auxiliary signal H with the setpoint generator output signal A and for generating an output signal χ which at most causes the maximum specified acceleration for H Ζ> · A and an output signal y causing at most the maximum predetermined delay for H <CA, by an integrator device for forming the output signal A from the signals χ and y, and by a feedback device.

The auxiliary variable H can be reduced so that it has dropped to zero at the end of the distance or has reached a value shortly before the end of the distance, which corresponds to the positioning speed. In the event that a mark is placed on the route and the starting point is in front of the mark, the reduction of the auxiliary variable H is only made when the mark is passed.

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took. The auxiliary variable H represents a lower limit, below which the setpoint must not drop in the deceleration range, so that the drive does not reach the stopping point comes to a standstill or a greater part of the path is covered at the positioning speed must become. In this way, quick and, at the same time, safe positioning is achieved. the Auxiliary variable H is set to a value at the start of the journey that is equal to or greater than the setpoint for is the maximum speed and corresponds to the speed from which the drive is under worst-case. Delay conditions on the route between the starting point and the stopping point or between the marker and the stopping point can.

The auxiliary variable H is particularly advantageously obtained by discharging a capacitor. The charging voltage at the beginning the discharge, which can easily be changed, corresponds to the set start value of the auxiliary variable H. The for Driving distance proportional discharge of the capacitor and thus the corresponding proportional decrease of the Auxiliary signal H can either be achieved by coupling a tachometer generator to the drive motor, which is followed by an integration element, the output voltage of which for continuous discharge of the Capacitor ensures, or in such a way that a pulse generator is coupled to the drive motor, and this Pulses for capacitor discharge can be used. The decrease in the auxiliary signal H then follows Kind of a step function, but is still on average proportional to the travel distance.

CL

The KompjBratore device can also be designed in such a way that that with a small difference between the sizes A and H

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Output quantities between χ and y are generated, where the integrator is then designed so that the rate of change of its output A values between the maximum acceleration and the maximum deceleration.

Further features and details emerge from the remaining subclaims as well as from following description of some preferred embodiments and with reference to the drawings. Show:

Fig. 1 is a graphical representation

of the auxiliary signal H as a function of the distance S when using a pulse generator to generate the auxiliary signal H

FIG. 2 shows the same representation as in FIG

a mark M is attached along the route;

Fig. J5 shows a graph of the dependency

the sizes H, A, χ and y as a function of the distance s;

Fig. 4

and FIG. 5 a representation corresponding to FIG. 3 using a mark M along the route;

6 shows the dependence of the quantities A, H, ν accordingly

5, plotted as a function of the travel time t;

7 shows the dependence of the quantities H, A and the output signal depending on the compressor from the travel time, whereby the arrangement is made so that output values between χ (max) and y (max) are generated on the basis of the operating conditions shown in FIG. 6;

8 shows a graphic representation of the quantities H and K.

as a function of the route s in the operating conditions shown in FIG. 7;

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FIG. 9 is a graphic representation corresponding to FIG. 8, plotted as a function of the travel time t

Fig.IO a graphical representation of the dependence of the output signal A on the travel time t at Start up;

Fig.Il a circuit diagram of the setpoint generator according to the invention and ·

12 shows a circuit diagram of a further embodiment of the setpoint generator according to the invention.

The setpoint generator shown in Fig. II includes as essential components are the device 1 for generating the auxiliary signal H, the comparator device 2 and the Integrator device 3. The device 1 for generation of the auxiliary signal H in the exemplary embodiment has a pulse generator 4, which is connected to the motor shaft 5, only is shown schematically coupled. The auxiliary signal H is specified via a potentiometer 6, whereby the -Capacitor Cl is charged. As soon as the switch 7 is opened, the voltage across the capacitor Cl is reduced in accordance with the steps taken.

The comparator device 2 has a differential amplifier Pl to compare the auxiliary signal H and the output signal A of the integrator device 3. If the auxiliary variable H is greater than the output signal A (acceleration), the differential amplifier Pl its negative saturation voltage. The output current χ the Komptfratoreinrichtung 2 can be adjusted with the resistor Rl (maximum acceleration). If that Auxiliary signal H is smaller than the output signal A (delay), the maximum delay, i.e. the

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Output current y can be set with resistor R2. The integrator device jj, that of the comparator device 2 is connected downstream and which forms the output signal A corresponding to the setpoint value, consists of the Amplifier P2 and capacitor C2.

Another exemplary embodiment of the setpoint generator according to the invention is shown in FIG. Here, too, the essential components are the device I ¹ for generating the auxiliary signal H, the comparator device 2 ¹ and the integrator ^{device J 1} . In addition, an operational amplifier P5 is provided there in the comparator device 2 ¹ , which has a feedback R3 through which output values lower than the maximum values χ (max) and y (max) are achieved in the event of a small deviation between the output signal K and the output signal A for initial acceleration or deceleration. If K and A are equal, the output of the comparator device is 2 '. The feedback R4 of the integrator ^{device] 5 r} enables the rate of rise of the output signal A to increase with increasing values of K. The influence of this feedback is only effective through the diodes Ml and K2 as long as the output of P5 is less than zero, ie only during the acceleration, as long as K is greater than A.

To generate the auxiliary signal H, a tachometer generator 9 is used here, which is connected to the drive 5 as in detail not shown, is coupled.

Refer to the graphs in Figs refers to the use of a setpoint generator, as shown in Fig. 11, while the The graphical representations in FIGS. 7 to 10 explain the relationships that are maintained with a setpoint generator as shown in FIG.

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Pig. 1 shows the course of the auxiliary signal H as a function of the route when using a pulse generator coupled to the drive 4. Although the fine structure is in the shape of a staircase, the curve for H is approximately linear, i.e. proportional to the distance traveled. Will the switch 7 is not already closed at the start of the journey and thus the built-up via the potentiometer 6, the The voltage determining the level of the auxiliary signal H is immediately reduced, but rather the closing of the switch 7 by triggered a marker M arranged along the route S, the course shown in FIG. 2 results.

If the steps are small enough or if you are working with a continuously integrated tachometer voltage, you can the step curve in Fig. I and 2 in a straight line. In the further explanation it is assumed that although what has been said applies in the same way to a staircase-shaped course.

The speed setpoint is formed by the integrator device 3, the output signal A of which runs according to the maximum permissible acceleration if the output signal χ of the comparator device 2 is present at the input of the integrator device 3, and runs back in accordance with the maximum permissible delay if the output signal y is present at the input. The switching of the input of the integrator device J> between the values χ and y is accomplished by the comparator device 2, which compares the output signal A of the integrator device 3 with the auxiliary signal H. If H is greater than A, the comparator device 2 delivers the output signal x, if H is less than A, the comparator device 2 delivers the output signal j. The course of the variables H, A, χ and y together with the driving speed ν is shown in FIGS. 3 to 5 as a function of the driving distance S.

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Fig. J5 that no mark is used on the distance covered, for ¹ J- 5 and the withdrawal of the auxiliary signal H until passage of a mark M is made in the illustrations of FIG. Taking into account the case.

With regard to the course of the speed ν in FIGS. 3 to 5, the unfavorable case is assumed that the Drive 5 does not understand the maximum values for acceleration and deceleration provided by the setpoint generator can.

The inFig. The relationships shown in FIG. 5 are in FIG. 6 for a better understanding plotted again as a function of the travel time t. One recognizes the linearly increasing Setpoint A and the subsequent speed v with lower acceleration. In the area of delay the curve part Hl represents the course of the auxiliary signal H, which would result if the speed ν could follow the setpoint A, and if the setpoint A were set to the maximum delay so that it in turn the auxiliary signal H could follow. But since the delay of the setpoint A is less than the initial inclination the auxiliary variable H, is the actual course of the auxiliary signal H because of the initially greater speed steeper. The turning point for the transition of the setpoint A from the. Run-up phase (acceleration phase) in the Return (delay phase) occurs at the moment when H becomes smaller than A. This neither happens to one certain time-still-at a certain waypoint, however, represents the most favorable point for the respective operating circumstances, at which the delay occurs at the earliest begins. The actual start of the deceleration depends on how great the actual speed is at the time the inversion of the setpoint, or when the actual value becomes greater than the setpoint.

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- How to get out of Pig. 6 recognizes it is for the delay cycle It is unimportant whether the drive of the fflaximal delay specified by the return of the integrator device 3 can follow. In the flatter part of the setpoint curve, i.e. in the area in which the integrator output signal A follows the auxiliary signal H, but at the latest at the stopping point, the speed will have caught up with the setpoint., and thus the system deviation will be zero. This results from the assumption made at the beginning that the Auxiliary signal H is set to a value at the beginning of the journey that is equal to or greater than the setpoint for the is maximum speed and corresponds to the speed from which the drive is under worst-case Conditions with the maximum permissible deceleration on the route or on the remaining distance between the mark M and the breakpoint can delay.

In the case of a sensitive load, especially when transporting people, the requirement is that the course of the journey is jerk-free. For the setpoint generator, this means that the transitions between acceleration and final speed or final speed and deceleration should be rounded off. This will, as will those described below Further refinements are possible by means of a setpoint generator of the type shown in FIG. 12. There is the Komperatoreinrichtung 2 'designed so that at If there is a small difference between the quantities A and H, output quantities between χ (max) and y (max) can also be generated. The integrator} 'is designed so that for input variables between χ (max) and y (max), the rate of change of the output sine A Assumes values that lie between the maximum acceleration and the maximum deceleration. This measure is explained in FIG. 7 on the basis of the operating conditions shown in FIG. The rounding of the sol

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value curve leads to the fact that the first part of the deceleration path is covered at greater speed, which leads to a linearization of the temporal course of the auxiliary signal H in the delay range.

If extremely short travel times are important, it can make sense to use a larger Η curve To linearize the area of the deceleration path. In a further embodiment of the invention, this is made possible by that the auxiliary variable H is fed to the comparator device 2 'via a non-linear element 8. The non-linear element comprises an amplifier P6 and a non-linear feedback 8 '. Appropriately the non-linear element 8 'is designed in such a way that its output signal K is greater than H in the case of small values of H and approaches the value of H with large values of H. This measure is based on FIG. 8 the operating conditions of FIG. 7 are shown. FIG. 9 shows the time course corresponding to FIG. 8.

Another variant of the setpoint generator according to the invention relates to the acceleration. To jerk the To avoid starting, it is advisable to start with a low acceleration and then to increase it. This can be done according to the invention in that the rate of rise of the caused by the signal χ Output signal A of the integrator device 2 'is kept low and in addition the output of the integrator device 3 'is fed back to its input in such a way that the rate of rise of the output signal A increases with increasing values of A, as shown in Fig. 10. So that this return is the rounding off the setpoint curve does not interfere with the transition to the final speed or the deceleration, it can, if A is greater than H.

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Claims (8)

fo / kr MAN machine factory Augsburg-Nuremberg
Corporation Nuremberg, June 2, 1980 Claims © A method for regulating a positioning drive, in particular for transport cabins, with the aid of a setpoint generator, characterized in that an auxiliary signal (H), which corresponds to at least the maximum travel speed and deceleration, is reduced approximately proportionally to the travel distance (5), with the feedback signal
Output signal (A) of the setpoint generator compared and
the output signal (A) is thereby regulated down in accordance with the course of the auxiliary signal (H). 2. Setpoint generator for carrying out the method according to
Claim I, characterized by a device (i) for generating an auxiliary signal (H) approximately proportional to the route (5), by a comparator device (2) for comparing the auxiliary signal (H) with the setpoint generator output signal (A) and for generating one at most the maximum specified acceleration causing output signal (x) for (H) greater than (A) and one at most the maximum specified deceleration 17.8720 ./. 13QGS1 / Q148 causing output signal (χ.) for H A, by a Integrator device (3, 3 ') for shaping the output signal (A) from the signals (x) or (y), and through a feedback device (4). 3. Setpoint generator according to claim 2, characterized in that the device (I) for generating the auxiliary signal (H) has a capacitor (el) or (C3), a tachometer generator (9) coupled to the drive (5) and an integration element ( lo) for the integration of its output voltage. 4. Setpoint generator according to claim 2, characterized in that the device (I) for generating the auxiliary signal (H) a capacitor (C1) or (C3) and a pulse generator (4) coupled to the drive (5). 5. Setpoint generator according to one of claims I to 4, characterized in that the auxiliary signal (H) is fed to ^{the comparator device (2 1) via a non-linear element (8).} 6. Setpoint transmitter according to claim 5 »characterized in that \ that the output signal (K) of the non-linear element (8 ¹ ) is greater than (A) for small values of (H) and approaches the value of (A) for large values of (H). 7. Setpoint generator according to one of claims I to 6, characterized in that the output signal (A) of the integrator device (3 ¹ ) is fed back to its input in such a way that the rate of rise of the auxiliary signal (H) increases with increasing values of (A) . 8. Setpoint transmitter according to claim 7, characterized in that the feedback is only effective as long as (H) is greater than (A). 130Q51 / QU8 ORIGINAL INSPECTED