DE4492654B4 - Fault diagnosis in synthetic yarn mfr. - involves continuous measurement and evaluation of several parameters - Google Patents

Abstract

Fault diagnosis in synthetic yarn mfr. comprises continuous measurement of a first parameter, continuous evaluation of the obtd. measurement curve, and prodn. of an indication signal depending on the evaluation of the measurement curve or a derived curve. the novelty comprises continuous measurement and evaluation of A second (reference) parameter is continuously measured and evaluated and an indication signal is produced when fault-typical behaviour is detected in the first and second parameters.

Description

The The invention relates to a method according to the preamble of the claim 1.

Such a method is known for a false twist method by EP 0 207 471 A2 , It has been found that the thread tension measured behind a friction false twister is meaningful for the quality of the thread and the bobbin produced, as expected, if suitable indication values - in the known case: mean value - are obtained from the current measured value and a suitable evaluation is carried out. However, based on current knowledge, this only applies to false twist crimping processes.

In other methods of producing a synthetic thread, in particular in the spinning process, in the rapid spinning process, in the stretch spinning process and in the spinning-stretching process, the thread tension has no similar significance have it determined. This is particularly due to the greater complexity of such Procedure attributed to which many process parameters have different effects on the thread tension.

In the DE 38 11 437 A1 describes a method for checking the quality of textured threads, in which parameters of a thread are measured at two or more measuring points in the process in order to derive the quality of the thread produced therefrom. Such measurements are used to document the quality of a thread or to determine poor quality, but they are not suitable for the detection of errors in the production process and their diagnosis.

In the DE 30 05 746 A1 describes a thread treatment machine with a plurality of similar treatment stations. One or more process parameters are monitored at the treatment stations, and a signal can be triggered at one of the treatment stations if certain limit values are exceeded. All parameters are individually monitored for exceeding certain limits. With this procedure, an error signal can only be triggered if a parameter alone enables a statement to be made about the presence of this error. It has been found that often individual process parameters do not allow a comprehensive statement about the quality of the thread and the bobbin produced.

The The object of the invention consists in a running spinning process for one to obtain synthetic thread by measuring data that is meaningful for the quality of the thread and the bobbin produced. The data should therefore a quality statement about that generated product and / or process management and process correction allow by control or regulation. Also - in the event of an emergency a poor quality - the early one Interrupting the manufacturing process and avoiding rejects are said to allows become.

The solution results from claim 1.

Under In addition to the actual diagnosis, fault diagnosis is also intended of errors, the process monitoring carried out on the basis of an error diagnosis and implementation be understood. "Errors" are said to be the broadest Any deviations from normal process and thread parameters can be understood.

at the method according to the invention will first a first dependent on litigation process parameters measured continuously. The measured value curve measured in this way is continuously evaluated, and it becomes dependent from this evaluation or a curve derived from the measured value curve generates an indication signal. It will also be at least a second one process parameters dependent on the process control also continuously measured and evaluated. If at the first and at least one further process parameter If an error-typical behavior is determined, an indication signal is generated. The first and at least the second process parameter can differ from each other dependent his. This dependency becomes an error in the sense defined here to disturb, what the basis for forms a detection. The first and at least the second process parameter can of each other independently his. A mistake can disrupt this independence, i. H. which is the basis for the Detection-forming errors will result in a simultaneous change both process parameters to make noticable. Certain errors lead to typical changes the at least two process parameters, d. H. the process parameters show typical behavior.

In a first embodiment of the invention in the method, the at least two process parameters compared or correlated at the same time, and it becomes a Indication signal generated when the typical behavior on indicates a deviation from the normal course of the process.

In a further embodiment of the The method according to the invention links the at least two process parameters. If this link indicates an error-typical behavior with regard to the normal course of the process, an indication signal based on it is generated.

The The method is particularly useful when spinning a synthetic thread applicable. The winding speed can be higher than 2000 m / min and the thread through the winding device directly from the spinneret subtracted from. This creates a pre-oriented thread (pre-oriented yarn = POY). A POY can also be used to create a POY Intermediate godet. By further increasing the Winding speed can also achieve full orientation be, in particular by interposing a heater, so that a fully oriented, stretched thread is created (fully oriented yarn). On the other hand, is it also possible in the process one Turn on godet that pulls the thread from the spinneret, or to provide a drawing stage consisting of several godets. In departure from previous surveillance procedures there is no longer a one-dimensional monitoring by evaluation only one parameter. Rather, at least two parameters evaluated and insofar - so to speak - a two- or multi-dimensional consideration of the process performed by the observation results regarding the two or more parameters e.g. B. again compared at the same time or correlated with one another in time and / or linked to one another and from the link the error signal is obtained.

As process parameters and reference parameters are all variables that are considered on the running thread (thread temperature, thread tension = thread tension, Thread speed) of the resulting bobbin (diameter, weight, Bulging of the front edges = deviation from the ideal cylindrical Shape) or the machine parts that determine the process (speeds, Speeds, temperatures, torque absorption) running or can be measured intermittently from time to time.

It can be seen that not all changes in process parameters have an impact on quality. In order to increase the informative value of the synopsis, it is therefore particularly advantageous and expedient (claim 5) to first determine experience for each of the parameters of the course of the crisis by experience (targeted preliminary tests with artificially generated procedural deviations and crisis situations). Crisis courses are the courses of the respective parameter that are symptomatic of certain procedural or product errors. These can be absolute values, extreme values of the current measured value of the respective parameter, the temporal course, the first or second derivation of the measured value of the respective parameter, the standard deviation or any other greetings derived from the respective parameter, which are a reason for the error Is meaningful. In particular, it is possible to store characteristic profiles of at least one of these described variables in a memory as an error mask (claim 4). Various errors, e.g. B. lint or knots in the thread can be generated artificially, the effect of which on the observed parameters, in particular the thread tension, can be precisely registered and saved as a corresponding error mask. For this purpose, also on the unpublished own registration with the German file number DE 43 14 049.1 directed.

As Parameters come in particular the thread tension, the bobbin weight, the thread thickness, the thread temperature, or any other setting parameter such as B. spinning head pressure, pump speed, spinning head temperature, godet speed, Godet temperature into consideration. In particular come as reference parameters also take the programmed setting parameters into consideration, if none constant course of these setting parameters is specified. As such a programmed parameter comes in particular the traversing movement and the traversing speed into consideration, which is a decisive one Influence on have the course of the thread tension measured in the winding zone. In all of these cases it is necessary to take the readings or the derived quantities, which are first already distinguish by their dimension, in relation to each other to set and determine their interdependency. this will Needless in the method according to claim 7 Parameters, e.g. the thread tension at different points in the spinning process, e.g. within the stretching zone between two godets on the one hand and measured on the other hand in the take-up zone.

in the The invention is based on embodiments of the invention but not limited is presented, layed out.

1 shows schematically the process flow, namely a spinning process for the production and drawing of a chemical thread, in which one of the exemplary embodiments is used.

2 shows another embodiment of the invention, for which the description of 1 applies accordingly.

About the spinning process:
A thread 1 is spun from a thermoplastic material. The thermoplastic material is through a filling device 2 the extruder 3 given up. The extruder 3 is by an engine 4 driven. The motor 4 is controlled by an engine 8th controlled. The thermoplastic material is melted in the extruder. This is done on the one hand by the deformation work which is introduced into the material by the extruder. There is also a heater 5 in the form of a resistance heater provided by a heater control 50 is controlled. Through the melt line 6 with a pressure sensor 7 can be equipped, the melt reaches the gear pump 9 by pump motor 44 is driven. The pump motor is controlled by the pump 45 controlled in such a way that the pump speed can be adjusted sensitively. The pump 9 conveys the melt flow to the heated spinning box 10 , on the underside of which is the spinneret 11 located. From the spinneret 11 the melt occurs in the form of fine filament strands 12 out. The filament strands pass through a cooling shaft 14 , In the cooling shaft 14 is by blowing 15 an air flow directed transversely or radially onto the filament sheet. This cools the filaments.

At the end of the cooling shaft 14 the filament coulter through a preparation roller 13 into a thread 1 summarized and provided with a preparation liquid. The thread is removed from the cooling shaft and from the spinneret through a take-off godet 16 deducted. The thread wraps around the trigger godet several times. For this purpose, a cross is used to the godet 16 arranged overflow roller 17 , The overflow roller 17 is freely rotatable. The godet 16 is by godet motor 18 and frequency transmitter 22 driven at a preset speed. This take-off speed is many times higher than the natural exit speed of the filaments from the spinneret 11 ,

The deduction godet 16 follows a pair of stretch godets 19.1 , and 19.2. with another overflow roller 20.1 , and 20.2. The structure of both corresponds to the deduction godet 16 with overflow roller 17 , To drive the stretch godets 19.1 , respectively. 19.2. serve the. stretching motors 21.1 , and 21.2. with the frequency transmitters 23.1 , and 23.2 , The input frequency of the frequency transmitter 22 . 23.1 , and 23.2 , is controlled by the controllable frequency transmitter 24 evenly specified. In this way, the frequency transmitters can 22 . 23.1 , and 23.2. individually the speed of the trigger godet 16 or the stretch godets 19.1 , and 19.2. can be set. The speed level of trigger godet 16 and stretch godets 19.1 ., 19.2. however, is collective on the frequency generator 24 set.

The first stretch godet 19.1 , has a heater 53 , through which the godet jacket can be heated and the thread can be warmed up accordingly. As a result, the thread properties achieved by drawing can be influenced to a large extent. The temperature of the heater 53 is controllable by heating control 52 ,

From the last stretch godet 19.2 , the thread comes 1 to the so-called "head thread guide" 25 and from there into the traversing triangle 26 , Only in 2 is the traversing device 27 represented as a reversing thread roller and a traversing thread guide guided therein, which runs the thread over the length of the bobbin 33 back and forth (traverse stroke, double stroke). The thread loops behind the traversing device 27 one only in 1 shown contact roller 28 , The contact roller 28 lies on the surface of the coil 33 on. It is used to measure the surface speed of the coil 33 , The sink 33 is on a sleeve 35 educated. The sleeve 35 is on a winding spindle 34 clamped. The spindle 34 is by spindle motor 36 and spindle control 37 driven so that the surface speed of the coil 33 remains constant. As a result, the spindle speed decreases hyperbolically in the course of the winding travel. To the surface speed of the coil 33 To keep constant, the speed of the freely rotatable contact roller is used as the controlled variable 28 scanned on the contact roller shaft by means of a ferromagnetic insert and a magnetic pulse generator, and the spindle motor 36 controlled depending on the output signal of the pulse generator.

The traversing device 27 is driven by a traversing motor 56 , The traversing motor 56 is by a traversing control device 57 controlled ( 2 ).

Behind the second stretch godet 19.2 , is a thread tension sensor (= thread tension meter) 8th provided in the thread course. This generates a signal that represents the thread tension. The signal output by the thread tension sensor is smoothed before it is fed to the computer. To do this, the output signal is first sent to the filter 61 given up. In the filter 61 periodic changes in thread tension corresponding in frequency to the traversing frequency are smoothed. Therefore, only those changes appear in the thread tension output device that are caused by events other than short-term, high-frequency events. However, in the course of the thread tension force smoothed in this way, those thread tension force fluctuations which are based on a change in the traversing speed are now included. Changes in the thread tension are also caused by the traversing movement itself, ie by the thread being moved back and forth along the bobbin. The thread path between the head thread guide is lengthened and shortened 25 and the traversing device periodically with the result of a corresponding change in the thread tension. These thread tension changes have the same frequency as the traversing. The traversing frequency is predetermined by the number of double strokes (one back and forth movement of the traversing thread guide) per unit of time. Typical values are between 500 and 1500 double strokes / min. The influencing of the thread tension signal by these short-term fluctuations can also be eliminated by the output signal of the thread tension meter 8th about the filter 61 is given. This filter contains conventional electronic components which effect the desired smoothing of the output signal which is as adjustable as possible. A suitable setting of this filter ensures that even such thread tension changes that occur with the traversing frequency are eliminated and converted into an average value. However, using the invention, it is alternatively also possible to compare these thread tension fluctuations with a stored specification of the traversing frequency and only to further evaluate the difference signal as a reference value (see below for this). The signal adjusted for the high-frequency components is then fed to the thread tension output device.

In the device 48 the continuously measured thread tension is output as a thread tension record (thread tension record). The output signal of the device 44 becomes a computing unit 46 pre-go. In the calculator 46 the thread tension record can be saved for the entire winding trip or essential - selected - parts of the winding trip. At the same time, the thread tension signal is processed in a manner which is the subject of this application and of the exemplary embodiments described later.

The computer structure for all exemplary embodiments is shown identically for both figures. The computer first has a comparison unit 58 on. In an application example of the invention, this comparison unit has the task of changing the traversing speed of the traversing law memory 47 and the thread tension signal of the thread tension output device 48 to relate to each other. This determines to what extent the thread tension curve is dependent on the curve of the traversing speed. The temporal changes in the traversing speed are of particular interest. Both the amount of the change and the rate of change, that is the change derived over time, have an influence on the thread tension. Using previously determined conversion factors, the course of the traversing speed can be converted into a hypothetical tensile force, as would be caused by changing the traversing speed. As mentioned above, the changes that result from the traverse movement itself can also be included in this hypothetical tractive force curve. The determination of the conversion factors is described below. In any case, the hypothetical value of the thread tension derived from the traversing speed is subtracted from the actual value of the thread tension. The difference signal then shows the thread tension changes that have not been caused by the change in the traversing speed and the traversing movement. This thread tension signal is referred to as reference signal B in the context of this application. The described production of the reference signal also applies to the exemplary embodiment 2 instead, is not shown there. It is expressly pointed out that this reference signal, which is related to the change, already corresponds to the requirements of this application for multidimensional quality monitoring and is suitable for evaluation. Further dimensions of observation are described below. It should be mentioned that these further dimensions of observation also directly affect the thread tension signal 48 can be applied and lead to a similar increase in the significance of this thread tension signal. However, the reference to the specified traversing law described here results in a refinement of the statement.

The reference signal B is therefore a further comparison device 66 of the computer 46 given up. In this comparison unit, on the one hand, the reference signal obtained from the thread tensile force may be processed further to a variable derived therefrom, such as the mean value, the first or second derivative (change over time), the standard deviation, the roughness of the signal curve or the like. On the other hand, the reference value or the quantity derived from it is compared with another parameter. Basically, a process and / or a product parameter comes into consideration.

In 1 is the diameter of the coil as a further state parameter 33 continuously recorded or a size derived from the diameter. Weight is also considered as such a size. However, then there are disturbing factors such as the density of the winding, enclosed air, crossing angle or the like. with a. Therefore, the weight determined cannot be regarded as an absolute value. The speed of the spindle is used to measure the diameter 34 and the speed of the contact roller 28 measured on the surface of the coil. Ferromagnetic inserts are used for this 30 . 38 in the spindle 34 as well as the contact roller 28 as well as corresponding impulses 31 . 39 , During the speed of the contact roller 28 at the same time as a control variable for the adjustment of the spindle motor 36 via spindle control 37 serves (see above), the rotation number of spindle 34 also - what in connection with 2 is already pointed out - to control the traversing device 27 related. In addition, however, both signals are converted to diameter D. A computer unit is used for this 67 which both signals are given up. The diameter signal is then the comparison device 66 given up. Alternatively, a further signal can be derived from the diameter signal, that of the comparison device 66 is given up instead of the diameter signal or additionally. In particular, the square of the diameter or the first mathematical derivation of the square of the diameter can be considered as such a derived signal. Since the thread speed is constant, this derivative must also be a constant. The first derivative is namely proportional to the amount of thread supplied. Deviations therefore suggest that the process is disrupted. If in the comparison unit 66 it is found that these deviations coincide with disturbances in the thread tensile force, decisive conclusions can be drawn about the procedure and the product, be it the thread or the bobbin wound therefrom.

In the comparison facility 66 So there is a comparison of two state parameters. The word "comparison" is to be understood in the broadest sense. This can be a difference. First, a uniform order of magnitude must be established for both parameters. But it can also be a comparison in the non-mathematical sense. For example, crises, e.g. B. extreme values, are determined and ascertained whether the extreme values for both parameters coincide in time or are at least related in time. If there is such a temporal connection, this allows conclusions to be drawn about certain errors. The opposite can also apply; This means that if crises occur only for one of these variables, this can be an indication of certain errors or causes of errors.

As well Is it possible, that the Parameters related to each other after a certain weighting to be brought.

Ultimately, the output signal of the comparison unit 66 another comparison unit 59 specified. In this comparison unit, a comparison can be made with a setpoint, which is carried out by setpoint generator 60 is specified. The quality signal is formed from this comparison and output by the computer.

The quality signals Q, the - how previously described - generated have been processed as follows: The quality signal can be issued as a visual or acoustic alarm or as a record become. With the writing, the generated coil is marked and classified.

These output signals from the computer 46 can in particular be used as a controlled variable for regulating an adjustment parameter of the spinning and drawing process. The output signals of the computer 46 can also be used to identify the quality of the coils that have been produced using the method.

For this the setpoint generator creates tolerance values for the reference value or from it derived greetings, as well Define error limits, according to which it is measured whether a coil with A quality, B quality or as Committee too evaluate.

The quality signal Q can also only serve as an alarm signal and e.g. for interruption of the process and to avoid waste production.

The quality signal can - alternatively or additionally - in particular one or more of the control devices
22 for the route gallery 16 and or
23.1. . 23.2. for the second range of routes 19.1 , and or 19.2. to influence the stretching
24 to control the take-off speed,
45 to control the pump speed,
49 to control the extruder speed,
50 to control the heating device,
51 to control the cooling device (blowing speed)
37 to control the winding speed
52 to control the godet heating
45 to control the pump of the dosing device
be abandoned. The extruder control is particularly activated when there is no metering pump 9 is used. In this case, the extruder acts as a pump and by controlling the extruder control, ie the speed of the extruder can influence the output of the extruder.

If a dosing pump 9 the throughput can be used through the spinning head 10 and the spinneret 11 by controlling the pump control 45 , i.e. the speed of the metering pump 9 , to be influenced.

By controlling the cooling air control 51 cooling is affected. This affects the thread titer. In particular, it is also possible to influence the uniformity of the individual filaments by using special cooling devices by means of which the filament shares and / or the spinneret is cooled in sectors.

In the exemplary embodiments 1 and 2 If individual parts of the system are possibly interchangeable, other parameters are controlled accordingly in this case. In particular, the extruder can be replaced by a discharge pump and there are also various other possibilities for cooling the filament sheet. A further heating can also be specified in or instead of the stretching devices.

at Today's high speed spinning process can also stretch to fall away through godets. In this case, the thread is either through a single godet is pulled from the spinneret and to the winding head promoted or withdrawn directly from the winding device from the spinneret. On the other hand, the stretching can also be carried out by other elements, z. B. a further heating device, in particular a heating pipe replace or supplement his.

By triggering the trigger control 24 becomes the speed of the godet 16 and the godets 19.1 , and 19.2. influenced without changing the speed ratio. In this case, the drawing remains constant, but the thread speed is changed. This can influence the titer.

By controlling the stretch control 23.1 , or 23.2. becomes the speed ratio between the godets 19.1 ./ 19.2. / 16 influenced and thus changed the stretch ratio. By changing the stretch ratio, the strength ratio of the thread, but also the titer, can be changed.

Finally, the peripheral speed of the coil can also be controlled by the spindle control 33 by contact roller 28 is controlled by means of the quality parameter. This results in particular in influencing the bobbin structure and the thread tension with which the thread is deposited on the bobbin.

• – Änderung des Titers durch Verstellung der Pumpendrehzahl 44, der Heizung 5, durch Verschmutzung der Düse, durch Änderung der Abzugsgeschwindigkeit der Galette 16
• – Fehlen von Filamenten, z. B. durch Filamentbruch
• – Fehlen der Präparation (Verbrauch der Präparationsflüssigkeit, Störung der Präparationsrolle 13)
• – Änderung des Streckverhältnisses, z. B. durch Verschmutzung oder Abrieb der Galetten 16, 19.1., 19.2.
• – Änderung der Festigkeitseigerischaften, z. B. durch Führen der Heizung 53
• – Änderung der Aufwickelgeschwindigkeit, z. B. durch ungleichförmigen Lauf der Kontaktwalze 28.

On the other hand, the influencing parameters described above can be detected more reliably than previously with the method according to this invention, if it has previously been determined through tests that errors with regard to these influencing parameters lead to a characteristic course of the corrected parameters. In particular, the following can be recorded:

• - Change the titer by adjusting the pump speed 44 , the heater 5 , due to contamination of the nozzle, by changing the withdrawal speed of the godet 16
• - absence of filaments, e.g. B. by filament breakage
• - Lack of preparation (consumption of preparation liquid, disruption of the preparation roll 13 )
• - Change the stretch ratio, e.g. B. by dirt or abrasion of the godets 16 . 19.1. . 19.2.
• - Change in strength properties, e.g. B. by running the heater 53
• - Changing the winding speed, e.g. B. by non-uniform running of the contact roller 28 ,

It has already been pointed out in the illustrated exemplary embodiments that the quality signal can be obtained by looking at the thread tension and the bobbin weight, the thread tension and a thread tension measured at another point, the thread tension and the traversing law. Other parameters are:
The bulging of the end faces of the coil, which can be determined by optical or pneumatic scanning, noise generation and noise analysis, the coil weight.

In 2 An embodiment is shown in which the thread tension is specified as a further parameter, as it is between the two stretch godets 19.1 and 19.2 is measured. To do this, there is a between the two godets. Yarn tension meter 68 arranged. This thread tension meter determines the thread tension of the thread running in the stretching and fixing zone. This thread tension is determined on the one hand by the speed of the godets 19.1 and 19.2 , but also by the heating effect of the heating device 53 in the godet 19.1 as well as other factors. However, the thread tension fluctuation, which is caused by the winding and traversing - ie in the thread path after the - does not go into this thread tension

Galette 19.2 arises. The thread tension measurement by the thread tension sensor 68 is on the one hand much closer to the origin and processing of the thread, but on the other hand it is largely independent of further processing, in particular winding. The through the thread tension meter 68 and the thread tension meter 8th resulting courses, possibly after adjustment of the traversing influences, are accordingly in the comparison device 66 compared with each other. With this comparison, the temporal correlation of the course of crises etc. can be determined. You can see deviating trends. One can (determine singular events in one or the other zone). From all of this, quality statements can be obtained that are particularly meaningful for the process management and the quality of the product.

1

thread

2

filling

3

extruder

4

engine

5

heater

6

melt line

7

pressure sensor

8th

Yarn tension meter, Thread tension meter

9

pump

10

spinning head

11

jet

12

filaments

13

applicator roll

14

cooling shaft

15

quenching

16

godet

17

Guide roll

18

Drive motor, godet

19

godets

20

Via rollers

21

drive motors

22

frequency generator

23

Frequency generator, Stretching ratio control

24

withdrawing control

25

Yarn guide

26

Traversing triangle

27

Traversing device

28

contact roller

30

ferromagnetic inlay

31

pulse

33

Kitchen sink

34

spindle

35

winding tube

36

Drive motor, spindle motor

37

spindle control

38

ferromagnetic inlay

39

pulse

42

comparison circuit

44

pump motor

45

pump control

46

computer unit

48

Thread tension output device

49

Extruder control, motor control

50

heating control

51

cooling control

52

heating control

53

Galettenheizung

54

Logic component

55

rectangle

56

Traversing motor

57

Traversing controller

58

comparing unit

59

comparing unit

60

Setpoint generator

61

component, filter

62

Storage

63

Storage

64

filter

65

multiplication module

66

comparator

67

computer unit

68

Yarn tension meter

Claims (8)

Method for fault diagnosis in a manufacturing process of a synthetic thread, in which a first parameter dependent on the process control is continuously measured, the measured value curve thus obtained is continuously evaluated, and an indication signal is generated as a function of the evaluation of the measured value curve or a curve derived therefrom, characterized in that - At least a second parameter dependent on the process control is continuously measured and evaluated as a reference parameter - and that the indication signal is generated if a behavior typical of an error is found in the first and at least one further parameter. A method according to claim 1, characterized in that the comparing at least two parameters simultaneously or temporally be correlated and, if the simultaneous comparison or the temporal correlation to a typical behavior regarding the normal process flow indicate a comparison or correlation based Indication signal is generated. Procedure according to. Claim 2, characterized in that the linked at least two parameters and if the link for a typical behavior regarding the normal process indicates a link based on this link Indication signal is generated. A method according to claim 1 to 3, characterized in that the Deviation of the at least two parameters or their combination and / or temporal Correlation by comparison of the respective measured value courses or linked and / or temporally correlated courses with previously determined characteristic courses as an error mask in one Storage. Method according to one of claims 1 to 3, characterized in that - for at least one of the parameters dependent on the process control, crisis profiles are determined, stored and compared with the measured profile of the parameter for agreement, - a preliminary signal is generated if agreement, and - The actual occurrence of crisis situations is determined and the indication signal is generated by linking the other parameter, which is dependent on the process control, with the distant signal. Method according to one of claims 1 to 5, characterized in that that the Process parameters thread and / or coil parameters. Method according to one of claims 1 to 6, characterized in that that as Process parameters Thread tension in the winding zone and as a reference parameter Thread tension is measured in front of a godet, which - in the thread run - in front of the winding zone is arranged. Method according to one of claims 1 to 7, characterized in that that the shortcut is asymmetrical.