Description
Method and device for observing a movement profile of a weaving machine
The invention relates to a method and a device for observing a movement profile of a driven element of a weaving machine, in particular a movement profile of a heald shaft.
A weaving machine has various driven elements. The movements of the individual elements have to be coordinated with one another in time, the individual elements being capable of being driven either via one com-mon drive motor or via a plurality of independent drive motors.
Heald shafts of a weaving machine usually execute a linear move-ment between an upper (reversal) position and a lower (reversal) position. A gear is usually required for driving the heald shafts and converts a rota-tion movement of a drive motor into the linear movement. Possible driving gears are described, for example, in WO 2004/092465 A1 or WO 2004/092466 A1, to the content of which reference is hereby made in full. The movement of a heald shaft over one weaving cycle or a plurality of weaving cycles, which determine a weaving pattern, in relation to moments . of the weaving operation or of the weaving cycle is designated in the con-text of the invention as a movement profile of the heald shaft. A plurality of weaving cycles, after which the movement of the heald shaft or of another driven element is repeated, are designated as the weaving pattern.
It is known from JP 59-192749 to attach metal parts to one side of a heald shaft and sensors to a weaving machine side part lying opposite the side. The metal parts are attached to the side at fixed intervals and, during a movement of the heald shaft, are passed in succession past the sensors. When a metal part is passed, the sensor generates a signal, the succes-sive signals being counted. By the signals being counted, an opening of the shed can be determined, in which case a desired maximum opening angle can thus be fixed.

The movement profile of the heald shaft can be adapted to various weaving conditions by setting various actuating elements, such as, for ex-ample, a set screw for setting a stroke, the selection of a cam or the like. Such adaptation is also described, for example, in EP 0 520 540 A1. Set-ting usually takes place manually. However, it is not possible or is possible only with difficulty to ascertain whether the various manually adjustable ac-tuating elements have been set correctly.
It is known from JP 2000-064144 to determine an expected desired position of a heald shaft from a movement of an associated drive on the basis of the kinematics of a coupling gear and to check by means of sen-sors whether this desired position has been reached, in order thereby to draw conclusions as to faults in the movement profile.
The object of the present invention is to provide a method and a. de-vice for observing a movement profile, which enable a user to check and/or analyze the movement profile in a simple way, preferably during weaving operation.
This object is achieved by means of the subjects of claims 1 and 9. Advantageous embodiments may be gathered from the subclaims. The object is achieved, in particular, by means of a method for observing a movement profile of at least one driven element of a weaving machine, preferably of at least one heald shaft, comprising the steps of detection of at least one measured value, preferably of a plurality of measured values, wherein at least one actual position of the driven element, preferably of the heald shaft, at a definable measuring moment in a weaving cycle and/or an actual moment of the weaving cycle when a definable measuring position of the driven element, preferably of the heald shaft, is reached is detected, and determination of at least one characteristic value of the movement pro-file by means of the at least one detected measured value, preferably by means of the detected measured values.

The number of measured values necessary for detecting or observ-ing the movement profile of the element is dependent on a complexity of the associated movement profile, in particular on a number of possible ad-justable variables, by means of which a movement profile can be influ-enced. If more measured values are detected, fault correction is possible, in order thereby to improve the quality of observation. To observe the movement profile of a heald shaft, preferably three or four measured values are detected. The characteristic values detected by observation can be di-rectly analyzed and/or evaluated during weaving operation and/or be deliv-ered for subsequent analysis. As a result of observation, it is possible to detect the overall movement profile of the element and/or individual charac-teristic values, in particular detect these digitally. In addition, it is possible also to draw conclusions as to further boundary conditions from the meas-ured values. For example, it is possible to detect how many heald shafts are provided, whether specific heald shafts are present and the like.
In an embodiment of the method, there is provision whereby the characteristic value determined is at least one parameter of the movement profile of the driven element from the group comprising an amplitude, a height offset and an angular offset. A possible movement profile is usually known in advance and/or can be approximated by means of an approxi-mately sinusoidal curve, so that, by individual parameters being deter-mined, the overall movement profile can be reconstructed at least in an approximation. Depending on the complexity of the movement profile, these parameters may be sufficient to map the overall movement profile.
In another embodiment of the method, there is provision whereby the characteristic value determined is at least one characteristic position of a heald shaft from the group comprising an upper position, a lower position or an intermediate position of the heald shaft. The position of the heald shaft may in this case be determined absolutely, for example with respect to a base, or relatively, for example with respect to a crossing position of a plurality of heald shafts. Any desired position between the upper position and the lower position is designated as an intermediate position. Prefera-

bly, an intermediate position in which a plurality of heald shafts cross one another, as expected, during upward and downward movement can be de-tected.
In a further embodiment of the method, there is provision whereby the characteristic value determined is at least one parameter of a coupling mechanism between a drive motor and at least one heald shaft from the group comprising a cam form, a stroke and an eccentricity of an eccentric of a dobby or of an eccentric mechanism. In this case, it is possible to ana-lyze whether a desired value of an actuating element, for example a stroke, to be set manually coincides with an actual value observed. In the absence of coincidence, a corresponding indication can thus be delivered to the user for a necessary correction.
In yet another embodiment of the method, there is provision whereby, before an observation of the movement profile, characteristic val-ues of a plurality of possible movement profiles are determined as a func-tion of at least one adjustable setting element, in particular as a function of at least one adjustable setting element of a coupling mechanism between a drive motor and a heald shaft. The characteristic values determined in ad-vance may be stored in table form or the like, so that, based on the meas-ured values, the characteristic values and consequently a specific move-ment profile can be read off from the table.
In a further embodiment of the method, there is provision whereby the at least one characteristic value of the movement profile during weaving operation is observed in a slow run and/or during a standstill. Particularly due to the possibility of observing the movement profile during weaving operation, it is possible to take into account influences on the movement profile which arise as a result of a dynamic movement of the driven ele-ment. In some instances, however, it may be advantageous to determine the characteristic values in a slow run, so that a correcting action can thus be taken.

In a further embodiment of the method, there is provision, further, whereby the at least one characteristic value and/or the observed move-ment profile is illustrated graphically. Graphical illustration may in this case take place during weaving operation, preferably in real time, and/or in a subsequent analysis.
In a further embodiment of the method, there is provision, further, whereby the determined characteristic value is compared with an associ-ated desired value. It is thus possible to give a user indications of how pos-sible adjustable variables can be corrected. In all the embodiments, a set-ting of the variables takes place in a self-regulating manner, in which case control strategies may be provided in order to prevent abrupt changes in the actuating variables. In a subsequent analysis, it is possible to analyze the quality of weaving operation as a function of the observed movement.
The object is achieved, further, by means of a device for observing a movement of a driven element of a weaving machine, preferably of a heald shaft, comprising a detection arrangement for detecting at least one meas-ured value, preferably a plurality of measured values, wherein at least one actual position of the driven element, preferably of the heald shaft, at a de-finable measuring moment in a weaving cycle and/or an actual moment of the weaving cycle when a definable measuring position of the driven ele-ment, preferably of the heald shaft, is reached is detected, and an evalua-tion arrangement, by means of which at least one characteristic value of the movement profile can be determined by means of the at least one de-tected measured value, preferably by means of the detected measured values.
In one embodiment, the detection arrangement comprises a camera, in particular a digital camera. It is possible by means of the camera to re-cord the driven element, preferably the heald shaft, at at least one measur-ing moment and/or in at least one measuring position. Depending on the design of the camera, in this case an instantaneous recording or a move-ment recording is possible, in order thereby to observe the movement pro-

In one embodiment, the detection arrangement has alternatively or additionally at least one sensor from the group comprising Hall sensors, distance sensors, laser sensors and optical sensors. By means of sensors of this type, individual positions can be detected reliably. Depending on the design of the sensor, a cost-effective detection arrangement having high robustness can thus be provided. By the determination according to the invention, which is carried out taking into account and/or with the knowl-edge of conceivable movement profiles, it is possible to use cost-effective digital sensors. In this case, it may be sufficient for a sensor to signal merely that a measuring position is reached.
In a further embodiment, the evaluation arrangement is designed to detect at least one characteristic position of the movement profile from the group comprising an upper position, a lower position or an intermediate position, at least one parameter of the movement profile from the group comprising an amplitude, a height offset and an angular offset, and/or at least one parameter of a coupling mechanism between a drive motor and the driven element, preferably the heald shaft, from the group comprising a cam form, a stroke and an eccentricity of an eccentric of a dobby or of an eccentric mechanism.
In an advantageous embodiment, the device comprises at least one storage arrangement coupled to the evaluation arrangement, in each case at least one characteristic value of a plurality of movement profiles being stored in the storage arrangement as a function of at least one adjustable variable of the coupling mechanism. The characteristic values can be de-termined in advance by means of suitable tests, a setting of adjustable variables taking place with high accuracy, for example using high-resolution measuring sensors and the like. It is then possible, during weaving opera-tion, first to set the variables manually, without aids, and, if appropriate, to correct the setting of the variables on the basis of the characteristic values observed.

In a further embodiment, moreover, an indicator arrangement for a graphical illustration of the at least one characteristic value and/or of the observed movement profile is provided. The graphical illustration makes it possible to have a simple evaluation of the observed movement profile.
In an advantageous embodiment, the evaluation unit comprises means for comparing the observed movement profile with a desired move-ment profile. The user can in this case be given indications, for example in the form of acoustic and/or optical signals, of how the observed movement profile can be adapted to a desired movement profile.
Further advantages of the invention will be gathered from the sub-claims and from the following description of exemplary embodiments of the invention which are illustrated diagrammatically in the drawings. Uniform reference symbols are used in the drawings for identical or similar compo-nents. Features described or illustrated as part of an exemplary embodi-ment may likewise be used in another exemplary embodiment in order to obtain a further embodiment of the invention.
In the drawings:
Figure 1 shows a partially sectional front view of a drive for heald shafts with a detection arrangement according to the inven-tion;
Figure 2a shows a view of a signal generator unit, integrated or attach-able on a heald shaft, for the detection arrangement accord-ing to the invention, as shown in figure 1;
Figure 2b shows a detail II according to figure 2a;
Figure 3 shows a view of a detection arrangement according to figure 1 attachable to a frame;

Figure 4 shows possible signals detected by the detection arrange-ment;
Figure 5 shows possible movement profiles reconstructed on the basis of the detected signals;
Figure 6 shows a graphical illustration of an observed position in a side view; and
Figure 7 shows possible movement profiles as a function of various adjustable parameters.
[0026] Figure 1 shows diagrammatically a partially sectional side view of a weaving machine with four heald shafts, only one heald shaft 1 being visible in figure 1. Figure 1 shows, further, an associated drive 2 which is coupled to the heald shaft 1 via a coupling gear 3. The drive 2 comprises a drive motor, not shown, with a drive shaft which is arranged in a housing 4. The drive shaft is configured as an eccentric shaft. The rotational movement of the drive shaft, not shown, is converted via the coupling gear 3 into a linear movement, illus-trated diagrammatically by an arrow P, of the heald shaft 1. The coupling gear 3 comprises, in the exemplary embodiment illustrated, a coupling rod 31, a connecting rod 32, two angle levers 33, 34, two transmission elements 35, 36 and a transmission rod 37. In the exemplary embodiment illustrated, a con-nection between the coupling rod 31 and the connecting rod 32 can be varied by means of a set screw 5. Further, a height of the heald shaft 1 can be set by means of a set screw 6 on the frame of the heald shaft 1. The coupling gear 3 illustrated is merely exemplary. Other conceivable coupling gears are de-scribed, for example, in WO 2004/092465 A1 and/or WO 2004/092466 A1, to the scope of which reference is made here in full. The drive shaft and the drive motor can be connectable to one another in various relative angular positions, in order thereby to achieve a desired angular offset. In this case, it is known, for example from WO 98/31856, to the content of which reference is likewise made in full, to provide a gearwheel which allows various relative angular posi-tions. In other configurations, other arrangements for setting and/or adjusting

an angular offset are provided.
According to the invention, a device for observing a movement pro-file of the heald shaft 1 is provided. The device comprises a detection ar-rangement 7 which, in the exemplary embodiment illustrated, cooperates with a signal generator unit 8, and a diagrammatically illustrated evaluation unit 9.
In the exemplary embodiment illustrated, the detection unit 7 is ar-ranged in such a way that it cooperates with a signal generator unit 8 pro-vided at a lateral margin of the heald shaft 1. Of course, this position is merely exemplary, and other positions, for example above and/or below the heald shaft 1, may be envisaged for arranging the detection unit 7.
The detection arrangement 7 illustrated has magnetic sensors which cooperate with magnets arranged on the signal generator unit 8. A possible arrangement of the magnets and of the magnetic sensors is described in more detail in connection with figures 2a, 2b and 3. In other embodiments, other sensors and/or arrangements may be provided.
Figure 2a shows diagrammatically the signal generator unit 8 ac-cording to figure 1. The signal generator unit 8 illustrated comprises a rail 80 which is attachable to the heald shaft 1 and to which four pairs of mag-nets, which have in each case a first magnet 8a and a second magnet 8b, are attached. Position pins 82 for the exact positioning of the magnets 8a, 8b are provided on the rail 80. The position pins 82 may be removed during operation. The rail 80 can be connected, for example adhesively bonded and/or screwed, to the heald shaft 1 according to figure 1. In other configu-rations, the magnets 8a, 8b are attached directly to the heald shaft 1. Fig-ure 2b shows diagrammatically a pair of magnets 83 with the magnets 8a, 8b in an enlarged illustration. As can be seen in figure 2b, the magnets 8a, 8b are in each case designed as bar magnets, the two bar magnets being arranged in a different orientation. A magnetic field is formed correspond-ingly on a surface, facing the detection arrangement 7, of the signal gen-

erator unit 8.
Figure 3 shows diagrammatically a detection arrangement 7 accord-ing to figure 1. The detection arrangement 7 comprises twelve magnetic sensors 71a to 71c, 72a, to 72c, 73a to 73c and 74a to 74c which are ar-ranged in four columns. Each column is in this case assigned to one heald shaft 1 according to figure 1, so that movement profiles of the four heald shafts 1 according to figure 1 can be observed by the detection arrange-ment 7 illustrated. The magnetic sensors or Hall sensors are connected to an electronic detection arrangement 70 which is connected to the evalua-tion unit 9 according to figure 1. In other configurations, the sensors may be arranged on the heald shaft. Preferably, however, the sensors are ar-ranged on the frame, so that simple cabling is possible.
The fields of the pairs of magnets 8a, 8b according to figures 2a and 2b can be detected by means of the sensors 71a to 71c, 72a to 72c, 73a to 73c and 74a to 74c.
Figure 4 shows magnetic fields diagrammatically, a distance from a center point of the pair of magnets 8a, 8b in an x-direction according to fig-ures 2a and 2b being plotted on the abscissa and a field strength being plotted on the ordinate. In this case, figure 4 illustrates three magnetic field signals I, II, III which differ from one another in their maximum field strength. To determine the three magnetic field signals I, II, III, a distance of the pair of magnets 8a, 8b from the detection arrangement 7 in a y-direction according to figures 2a and 2b has been varied, a distance on which the magnetic field signal I is based being shorter than a distance on which the magnetic field signals II and III are based. The shorter the dis-tance in the y-direction is, the higher the maximum field strength conse-quently is. In any event, however, a direction of the detected magnetic field changes upon passage through a "0 position". By the change in direction of the magnetic field, this position can be detected reliably independently of a magnitude of the magnetic field. Since the distance in the y-direction changes during weaving operation, it is advantageous that the change in

direction takes place independently of the distance in the y-direction and therefore the position can be detected reliably.
In the exemplary embodiment illustrated, in each case three sensors 71a, 71b, 71c and four pairs of magnets 8a, 8b are provided. A distance B between the pairs of magnets is virtually constant in the exemplary em-bodiment illustrated and amounts, for example, to B=25 mm. A distance C between two sensors 71a, 71b, 71c of the detection arrangement 7 accord-ing to figure 3 is in this case likewise virtually constant and amounts, for example, to C=37.5 mm, that is to say 1.5 x the distance B. The sensors 71a, 71b, 71c and the pairs of magnets 8a, 8b are arranged, for example, in such a way that the lowest pair of magnets 83 according to figure 2a is arranged above a lower sensor 71c when the heald shaft 1 according to figure 1 is in an upper position. During a downward movement out of this upper position, one pair of magnets after the other is then moved past the position of the lower sensor 71c. In this case, a detected signal can be as-signed in a simple way to a specific pair of magnets 8a, 8b. Thus, by means of the sensor 71c, four signals according to figure 5 for a heald shaft 1 according to figure 1 can be detected, that is to say the reaching of four positions can be detected. By means of the further sensors 71a, 71b, it is possible, in the exemplary arrangement, to detect a new signal at the dis-tance of 0.5 x B after a movement of 12.5 mm.
Based on these signals, therefore, moments within a weaving cycle at which the heald shaft 1 assumes specific positions can be determined as measured values.
According to the invention, on the basis of these measured values, at least one characteristic value of a movement profile and/or the overall movement profile of the heald shaft 1 are/is reconstructed.
Figure 5 shows diagrammatically a graphical illustration of two movement profiles, in each case the moments or angular positions at which the specific positions have been reached being depicted as measured val-

ues P1, P2 and P3 and P1*. P2* and P3*. In this case, it can be seen that a first movement profile, illustrated by an unbroken curve, fits with the meas-ured values P1, P2, P3, whereas a second profile, illustrated by a line of dashes, fits with the measured values P1*, P2*, P3* It can thus be ascer-tained from the measured values P1, P2 and P3 and P1*. P2* and P3* which movement profile is involved. Conversely, it is thus also possible, for example, to draw conclusions as to the settings carried out by means of the set screw 5 and/or the set screw 6 according to figure 1.
The movement profiles of the heald shaft 1 can be processed graphically for analysis. In addition to the illustration for the movement pro-file by the angular position, as depicted in figure 5, it is in this case also possible to process graphically an opening of the heald shafts in a side view, as illustrated diagrammatically in figure 6, for each moment of the weaving cycle and/or angular positions and thus make it available to the user.
As already mentioned, the movement profiles of a heald shaft 1 and/or of other driven elements of the weaving machine are dependent on various variables or parameters. Figure 7 shows diagrammatically five dif-ferent movement profiles of heald shafts as a function of various variables or parameters. By means of the values detected by the device according to the invention, it is possible to ascertain which of the possible movement profiles illustrated in figure 7 is actually present. The determination of an associated movement profile is possible, for example, by means of what is known as curve fitting or the like. Preferably, however, the determination of an associated movement profile takes place on the basis of tables or the like, in which desired values for possible movement profiles are stored. By the measured values being compared with the desired values, a movement profile and/or an associated characteristic value can thus be determined. The values of the tables can be determined by means of tests or the like in advance, and the values can be stored in a suitable storage arrangement.
In the exemplary embodiment illustrated in figure 7, a stroke length

has been varied by means of the set screw 5 according to figure 1, a height of the heald shaft 1 by means of the set screw 6 according to figure 1 and an angular offset, for example, by a variation in the relative angular position between the drive shaft and drive motor. In this case, a first curve 1, illus-trated by dots, shows the movement profile in the case of a stroke length of 80 mm, a height offset of 0 mm and an angular offset of 0°. In the second curve 2, illustrated by an unbroken line, and the third curve 3, illustrated by dashes and dots, the stroke lengths have been varied with respect to the first curve 1. The stroke length in this case amounts to 100 mm in the sec-ond curve 2 and to 120 mm in the third curve. In the curves 4 and 5, the height offset and the angular offset have been varied with respect to the second curve 2 illustrated by the unbroken line. In contrast to the move-ment profile illustrated by the second curve 2, a height offset of 20 mm is set in the movement profile illustrated by the curve 4 represented by dashes and double dots. In the movement profile illustrated by a dashed curve 5, an angular offset has been varied with respect to the movement profile illustrated by the unbroken curve 2. In this case, in the movement profile according to curve 5, the angular offset amounts to 20°. In figure 7, the ordinate is subdivided at the distance of 12.5 mm. This subdivision cor-responds to the distance of 0.5 x B in the abovementioned numerical val-ues. The intersection points of curves 1 to 5 illustrated with the scaling lines running parallel to the abscissa can consequently be determined by means of sensors, for example the Hall sensors. An associated curve and, conse-quently, an associated movement profile can be determined on the basis of these points.
The intersection points of conceivable curves can be stored in ta-bles, and, for example, during weaving operation an angular position pre-sent when the position 12.5 mm is reached is detected and compared with the values of the table. On the basis of the comparison, at least one char-acteristic value of the present movement profile and/or the movement pro-file as a whole can be determined.
According to the invention, the determination and/or graphical proc-

essing of a determined or observed movement profile is possible during weaving operation, preferably in real time. In this case, setting instructions for the setting of variables, such as, for example, the set screw 5 and/or the set screw 6 according to figure 1, can be made available to a user. The determination and/or graphical processing are/is in this case possible both in a normal run and in a slow run.

We claim:
1. A method for observing a movement profile of at least one driven
element of a weaving machine, preferably of at least one heald shaft
(1), comprising the steps:
a. Detection of at least one measured value, preferably of a plu-
rality of measured values, wherein at least one actual position
of the driven element, preferably of the heald shaft, at a de-
finable measuring moment in a weaving cycle and/or an ac-
tual moment of the weaving cycle when a definable measur-
ing position of the driven element, preferably of the heald
shaft (1), is reached is detected, and
b. Determination of at least one characteristic value of the
movement profile by means of the at least one detected
measured value, preferably by means of the detected meas-
ured values.
2. The method as claimed in claim 1, characterized in that as charac-teristic value at least one parameter of the movement profile of the driven element from the group comprising an amplitude, a height off-set and an angular offset, is determined.
3. The method as claimed in claim 1 or 2, characterized in that as char-acteristic value at least one characteristic position of a heald shaft (1) from the group comprising an upper position, a lower position or an intermediate position of the heald shaft, is determined.
4. The method as claimed in claim 1, 2 or 3, characterized in that as characteristic value at least one parameter of a coupling mechanism between a drive motor and at least one heald shaft from the group comprising a cam form, a stroke and an eccentricity of an eccentric of a dobby or of an eccentric mechanism, is determined.

5. The method as claimed in one of claims 1 to 4, characterized in that, before an observation of the movement profile, characteristic values of a plurality of possible movement profiles are determined as a function of at least one adjustable setting element, in particular as a function of at least one adjustable setting element (5, 6) of a cou-pling mechanism (3) between a drive motor and a heald shaft (1).
6. The method as claimed in one of claims 1 to 5, characterized in that the at least one characteristic value of the movement profile during weaving operation is observed in a slow run and/or during a stand-still.
7. The method as claimed in one of claims 1 to 6, further comprising the step
c. graphical illustration of the at least one characteristic value
and/or of the observed movement profile.
8. The method as claimed in one of claims 1 to 7, further comprising
the step
d. comparison of the determined characteristic value with an as-
sociated desired value.
9. A device for observing a movement of a driven element of a weaving
machine, preferably of a heald shaft (1), comprising a detection ar-
rangement (7) for detecting at least one measured value, preferably
a plurality of measured values, wherein at least one actual position
of the driven element, preferably of the heald shaft (1), at a definable
measuring moment in a weaving cycle and/or an actual moment of
the weaving cycle when a definable measuring position of the driven
element, preferably of the heald shaft (1), is reached is detected,
and an evaluation arrangement (9), by means of which at least one
characteristic value of the movement profile can be determined by
means of the at least one detected measured value, preferably by
means of the detected measured values.

10. The device as claimed in claim 9, characterized in that the detection
arrangement comprises a camera, in particular a digital camera.
11. The device as claimed in claim 9, characterized in that the detection
arrangement (7) has at least one sensor from the group comprising
magnetic sensors (71a, .... 74c), in particular Hall sensors, distance
sensors, laser sensors and optical sensors.
12. The device as claimed in one of claims 9 to 11, characterized in that
the evaluation arrangement (9) is designed to detect at least one
characteristic position of the movement profile from the group com-
prising an upper position, a lower position or an intermediate posi-
tion, at least one parameter of the movement profile from the group
comprising an amplitude, a height offset and an angular offset
and/or at least one parameter of a coupling mechanism (3) between
a drive motor and the driven element, preferably the heald shaft (1),
from the group comprising a cam form, a stroke and an eccentricity
of an eccentric of a dobby or of an eccentric mechanism.
13. The device as claimed in one of claims 9 to 12, further comprising at
least one storage arrangement coupled to the evaluation arrange-
ment (9), in each case at least one characteristic value of a plurality
of movement profiles being stored in the storage arrangement as a
function of at least one adjustable variable of the coupling mecha-
nism (3).
14. The device as claimed in one of claims 9 to 13, further comprising
an indicator arrangement for a graphical illustration of the at least
one characteristic value and/or of the observed movement profile.
15. The device as claimed in one of claims 9 to 14, characterized in that
the evaluation unit is designed to compare the observed movement
profile with a desired movement profile.

The invention relates to a method and a device for observing a movement profile of at least one driven element of a weaving machine, preferably of at least one heald shaft (1), comprising the steps: detection of at least one measured value, preferably of a plurality of measured values, wherein at least one actual position of the driven element, preferably of the heald shaft, at a definable measuring moment in a weaving cycle and/or an actual moment of the weaving cycle when a definable measuring position of the driven element, preferably of the heald shaft (1), is reached is detected, and determination of at least one characteristic value of the movement profile by means of the at least one detected measured value, preferably by means of the detected measured values.