EP3074333A1

EP3074333A1 - Traversing unit and method for controlling a traversing unit

Info

Publication number: EP3074333A1
Application number: EP14802409.4A
Authority: EP
Inventors: Markus RÜTER
Original assignee: Oerlikon Textile GmbH and Co KG
Current assignee: Oerlikon Textile GmbH and Co KG
Priority date: 2013-11-28
Filing date: 2014-11-20
Publication date: 2016-10-05
Anticipated expiration: 2034-11-20
Also published as: JP2016538208A; CN105722776B; CN105722776A; JP6490072B2; EP3074333B1; WO2015078763A1

Abstract

The invention relates to a traversing unit for guiding a thread and to a method for controlling such a traversing unit. The traversing unit has a motor (170) with a driveshaft (171) for driving a thread guide (120), said motor being connected to a controller (330). The controller is connected to an incremental encoder (180) which is coupled to the driveshaft of the motor. The aim of the invention is to allow an analysis of the incremental angle signals of the incremental encoder dependent on the guiding speed of the thread guide. According to the invention, this is achieved in that the controller has a first QEP analysis unit (320-1) for generating a first data stream and a second QEP analysis unit (320-2) for simultaneously generating a second data stream.

Description

Changiereinheit and method for controlling a traversing unit

The invention relates to a traversing unit and a method for controlling a traversing unit of a yarn for winding a cross-wound coil. In particular, the invention relates to a control for a thread guide, in which a thread guide attached to a toothed belt exactly changes a thread.

Threads or yarns or also fibers and filaments are wound on spools after being produced and after processing steps. It is understood in the literature and the term Spulgut every thread or band-shaped material, which can be spooling example, in the cross spool on a spool or a winding. Subsequently, the term thread is used for this purpose.

The thread is thereby fixed with its beginning on a spool core, so that the thread drawn during rotation of the spool core on this and thus the thread is wound or wound on the spool core and so thread windings. If the thread is not guided in such a winding operation, then the thread windings are typically not arranged next to one another in an orderly fashion. Such coils are almost unusable for machine further processing, since the thread can not be unwound uniformly and breaks accordingly fast. Accordingly, an orderly winding is necessary in which the individual thread windings are defined adjacent to each other. In a manner known per se, the yarn to be wound up is guided by means of a yarn guide device, that is, it changes that the yarn windings are arranged next to one another on the drum. le be pulled. The yarn is thereby guided uniformly over the entire width of the resulting coil, ie over the traverse stroke, wherein the yarn guide device is typically guided parallel to the coil axis in a transverse movement.

During the winding of the coil, the thread should be guided as precisely as possible so that the individual windings of the thread are deposited as precisely as possible on the bobbin, and thus the thread can be correspondingly accurately and evenly unwound from the bobbin. At the same time, the traversing unit should, on the one hand, guide the thread as precisely as possible, but at the same time the thread guide should be sufficiently fast, so that the thread can be laid on the spool with the greatest possible speed.

The traversing unit can have a thread guiding slide, a so-called thread guide, with an eyelet leading to the thread, the thread guide being fixed to a belt, for example a toothed belt. The yarn guide can be guided in a guide rail and driven by a motor-driven wheel, such as a toothed belt. Thus, the drive motor determines the movement of the thread guide via the drive wheel and the belt. Accordingly, for the most accurate possible positioning of the thread guide and a correspondingly precise filing of the thread on the spool of the motor must be controlled so that the thread guide is positioned quickly and accurately. Such a traversing unit and a generic method for controlling a traversing unit are known, for example, from DE 103 22 533 A1. In the known traversing unit, the motor-driven Driven thread guide back and forth within a traverse stroke. In this case, the motor is controlled as a function of an actual position of a rotor shaft of the motor, wherein the rotor shaft is impressed with an additional lead by an advance angle. However, such controls can lead to significant deviations of the desired target positions and in particular to significant deviations of the desired speeds, especially in the reverse areas of the thread guide.

A further traversing unit and a generic method for controlling a traversing unit are known from WO 199/00 50 55. In the known traversing unit, the motor-driven thread guide is detected in its position within a traversing stroke and controlled in dependence on an actual-target comparison by a change in the angular velocity. For detecting the actual position of the thread guide, an angle encoder is coupled to the drive motor and connected to a control device. In this case, a high measuring accuracy of the actual position is required in order to obtain an exact guidance of the thread guide. In particular, the different movement sections of the thread guide and the associated different guide speeds place a particularly high demand on the measuring accuracy of the angle sensor.

It is therefore an object of the invention to provide a traversing unit and a method for controlling a traversing unit, in which or which the motor guides the yarn guide, in particular at the ends of the traverse stroke for depositing the yarn on a bobbin surface with high precision. This object is achieved with a traversing unit according to the features of claim 1 and with a method for controlling a traversing unit with the features of claim 8. Advantageous developments of the invention are defined by the features and feature combinations of the respective subclaims.

The invention takes into account the different movement sections of the yarn guide, which must undergo oscillating a traverse stroke. Especially in the reversal areas of the traverse stroke, rapid angular velocity changes of the yarn guide are required. In that regard, particularly fast control paths with the highest accuracy are desired in the reverse area of the thread guide. In order for such fast controlled systems in a linear region of the yarn guide with substantially constant guide speed produces no false responses, the traversing unit according to the invention has a control with a first QEP evaluation unit (QEP = Quadrature Encoder Pulse) for generating a first data stream and a second QEP evaluation unit for simultaneous Generation of a second data stream. Thus, it is possible to evaluate the angle increment signals generated by the angle sensor in a differentiated manner and to obtain from them a control of the motor which is preferred for the movement section of the thread guide.

In particular, it is thus advantageous if the first QEP evaluation unit is programmed with a first clock frequency for high angular speeds of the drive shaft and the second QEP evaluation unit is programmed with a second clock frequency for low angular speeds of the drive shaft. wave is programmed. Thus, by means of different sampling rates, corresponding measurement accuracies can be generated, which are reflected in the data streams of the QEP evaluation units. Thus, the first clock frequency of the first QEP evaluation unit is preferably determined to generate a clock for an interval of a number of N angle increments, where N> 2. The second clock frequency of the second QEP evaluation unit is intended to generate a clock for each separate angle increment. Thus, the incremental increment signals generated by the incremental encoder can be evaluated according to the prevailing angular velocity and used to control the motor.

In order to obtain a favorable control of the motor for each movement section of the thread guide, a data stream coupler is furthermore provided within the control device, which is connected to the QEP evaluation units and which, depending on a predetermined angular velocity, one of the data streams of the QEP evaluation units for controlling the Motors releases.

For the transmission of the angle increment signals to the QEP evaluation units, a signal conditioning unit is furthermore provided, by means of which a duplication of a signal of the incremental encoder can be generated. This gives the QEP evaluation units identical signals without any distortion. Moreover, it is particularly advantageous if the signal conditioning unit has an optocoupler through which the transmission of the doubled angle increment signals takes place. This allows the incremental encoder to be galvanically isolated from the QEP evaluation units. In order for electrical disturbances in the transmission of Winkelinkrementsignale can be advantageously avoided.

The invention will be described in more detail with reference to figures and explained. Show

Figure 1: a diagram of a traversing unit for guiding a thread during winding;

FIG. 2 shows a schematic representation of the signals of the incremental encoder;

Figure 3: a schematic arrangement of the traversing unit according to the invention

1 shows a schematic illustration of a traversing unit 100 which could be arranged on a mounting plate and in which a thread 110 is guided through an eyelet of a thread guide 120. The yarn guide 120 is coupled to a belt 130, in this case a toothed belt, ie, in the embodiment described here, the yarn guide 120 is firmly attached to the toothed belt 130. The belt 130 passes over a drive wheel 140, here a gear for the toothed belt, and over two pulleys 150-1 and 150-2. Between the two pulleys 150-1 and 150-2, the belt is guided by a guide rail 160. The yarn guide 120 is attached to the belt 130 in such a way that it slides in the guide rail. ne 160 between the pulleys 150-1 and 150-2 runs. The drive wheel 140 is connected to a drive shaft 171 of an electric motor 170, which moves the belt 130 and thus the yarn guide 120 via the drive wheel 140, so that it is reciprocated between the two deflection rollers 150-1 and 150-2. In this case, in the embodiment described here, the drive shaft 171 of the motor 170 at the same time the axis of rotation of the drive wheel 140, so that each rotational movement of the motor 170 is exactly transferred to the drive wheel 140. As an alternative to this direct coupling between the drive wheel and the motor, the motor and the drive wheel can also be connected to one another, for example, via a gear or the like for transmitting the rotational movement.

The motor 170 may be a stepper or servo motor connected to a corresponding power and control electronics.

A rotational movement of the motor 170 thus leads to a rotational movement of the drive wheel 140, which in turn moves the belt 130, so that the belt 130 and thus the yarn guide 120 coupled to the belt 130 performs a translational movement between the two deflection rollers 150-1 and 150-2 , The distance of this movement between the two points of origin of the movement is thus the traverse stroke.

The movement of the thread guide 120 is particularly important at the Urnkehrpunkten of importance. In this case, the point of origin of the translational movement of the thread guide 120 must be maintained exactly, so that the thread on the spool exactly reverses its depositing direction and strikers are avoided. A so-called Abschläger is a thread winding, the next to the previous coil windings falls directly on the coil axis. Such beaters cause the thread would tear during unwinding on reaching the Abschlagägers. Bobbins with such beaters are unusable for many machine applications.

For precise positioning and movement of the thread guide 120, the traversing unit 100 has a rotary or incremental encoder 180, which determines the rotation of the drive shaft 171. In the embodiment shown here, the incremental encoder 180 is mounted directly on the drive shaft 171 of the motor 170 and thus directly determines the rotation of the drive shaft 171. Alternatively, the incremental encoder may be coupled to the drive shaft of the motor, for example via a gearbox or a similar mechanical connection to determine the rotation of the drive shaft 171.

In operation, the incremental encoder 180 outputs an angle increment signal representing a rotation of the drive shaft 171 of the motor 170. The angle increment signal itself can be arbitrary, ie it can be a light signal or an electrical signal. In the embodiment described here, the incremental encoder 180 outputs an electrical angle increment signal. In one embodiment, this may be a conventional US-E6-2000 incremental encoder. It supplies 8,000 angular increments per revolution of the drive shaft and, if all signal edges are evaluated, the information on two incremental signals is output for this incremental encoder. FIG. 2 shows a schematic representation 200 of the electrical angle link signals of the tracks A and B, see 210 and 220, respectively, as they are output by the incremental encoder 180 at a constant angular speed upon rotation of the drive shaft 171. The signals shown schematically in FIGS. 210 and 220 show that with constant angular velocity of the drive shaft 171 equidistant pulses are output with equidistant time intervals, the pulses A and B being offset by a quarter period. Looking at the edges of the signal tracks A and B, this results in an information as shown in 230, wherein each edge is information about a change in the position of the drive shaft, a so-called. Lage- Iständerung.

From these signals supplied by the incremental encoder, both the angular velocity of the drive shaft 171, the direction of rotation and also the relative position of the yarn guide 120 can be determined. If, for example, one assigns the increment position 5 to a first position of the drive shaft, it can be seen that with each edge of a signal the drive shaft has rotated to the next angle increment, see 240. The speed, ie the angular velocity or rotational speed, of the drive shaft can be determined in a known manner from the temporal change of the angle φ, where φ can be determined by the number of angular increments covered:

φ ^T = angle increments ^■ ^ ^π // m _τ k, rement _^ zan, l, Thus, the angular velocity ω results as a time derivation of the

Angle φ

Are now during a fixed sampling time interval T _scan incoming Winkelinkrementinformationen added to AWinkelinkmmente, we obtain ω for the angular velocity

AWinke linkremente 7.71

00 =

T _Ahtn " _t Incrementz hl

Alternatively, the angular velocity of the drive shaft can be determined by means of the time T _event between the occurrence of two defined events, that is, a number of swept angle increments. Accordingly, the angular velocity then increases

2π

ω =

^T Event IncrementZtM

It should be noted that both of the determination methods described above can be used. The direction of rotation of the drive shaft can be determined in a conventional manner from the time sequence of the signals of the tracks A and B. If the levels of the two tracks A and B, see in Figure 2 signal 210 and 220, the signal generator, for example, to logic zero, the direction of rotation can be determined as to whether the next signal is a logical one first at track A or track B. is reported. By evaluating the respective states of the signals of the tracks A and B, the direction of rotation can thus be unambiguously determined in each case.

The determination of the absolute position of the drive shaft can take place on the one hand via a so-called Einrichtfahrt, wherein the yarn guide a certain position anfährt and this serves as a reference position for the subsequent relative position determinations. Such a reference position may in one embodiment be a reversal point of the thread guide. In an alternative embodiment, the incremental encoder can deliver a reference signal at a specific position, so that a reference position can be determined via this. As soon as the absolute position of the thread guide has been determined, the position in relation to the reference position can be determined using the methods described above. The maximum angular error of a position determined therewith, which can be determined on an angle increment, is thus the angular width of an angle increment

^Ύ / Increment number This angle ^error is therefore inversely proportional to the number of increments issued by the incremental encoder per axis revolution. About the geometry of the mechanical coupling to the thread guide, ie in the embodiment described here on the radius of the drive wheel, this angle error thus determines directly the position error of the thread guide.

However, this error is not achievable in practice, but is actually greater, since more errors are added to this principle-based error. These may include mechanical inaccuracies of the incremental encoder, such as mechanical inaccuracies, or signal delays that preclude the timely processing. This Accuracies can lead to a fluctuation around the theoretical value when determining the event time T _event .

Due to a temporal timing jitter of the angle increment signals, which is known in the art as so-called jitter, a fluctuation occurs in the real state. In that regard, different event times result in T _EventsM in and T _EventMm . The so-called jitter time t _jitter is of numerous

Influencing variables, such as the quality of the Winkelinkrementgebers and the clock frequency of an evaluation depending. Since the speed is measured over the event time, such effects must be taken into account in the determination of the angular velocity.

Furthermore, there is a further problem in practice if the sampling time for the signals provided by the incremental encoder is greater than the clock time at which the incremental signals are actually provided. For example, if the incremental values are sampled at a sampling rate of 20kHz, resulting in a sampling interval of T _sampling = while the motor is rotating at a maximum angular velocity, or speed, of 17 Hz and the incremental encoder providing the 8000 increment information per revolution mentioned above , this results in an event time between two increments of

T _event = 1 / (8000 ΠΗζ) = 7,35 / «.

As a result, multiple increment information (signal edges) are within one sample interval. Although these could be read in by an evaluation unit, the evaluation unit would only record the last event time in its memory, so that one of the evaluation units would newly determined event time would overwrite the most recently determined and stored event time. If the sampling interval is greater than the event time, then the controller only reads out the event time last saved by the evaluation unit. At a high speed of the engine so that not all event times are read by the controller from an evaluation unit. If, on the other hand, the number of increments to be evaluated is selected to be greater, so that the time interval between two angle increment signals increases at the same rotational speed, the achievable angle or position error becomes greater. Such an evaluation over several angular increments is disadvantageous in the reversing process, since the angular velocity is low, so that a higher resolution is possible. The higher resolution is desired during the reversing process, since a more exact control is required here. FIG. 3 shows a schematic 300 of the inventive traversing unit for solving this problem. In this case, the motor 170 is connected to the incremental encoder 180, which generates the increment signals as a function of the rotational speed of a drive shaft 171 of the motor 170. The angle increment signals output by the incremental encoder 180 are processed in a signal conditioning unit 310 and, following a duplication, subsequently fed to a first so-called QEP evaluation unit 320-1 (QEP = Quadrature Encoder Pulse) (QEP1) and a second QEP evaluation unit 320-2 (QEP2) , For this purpose, the signal conditioning unit 310 has an optocoupler 370, so that the incremental encoder 180 is galvanically decoupled from the QEP evaluation units 320-1 and 320-2. The QEP evaluation units 320-1 and 320-2 process the angle increment signals supplied by the incremental encoder 180 and Forward data streams generated therefrom of angle information to a controller 330 on. The QEP evaluation units can be implemented as separate functional blocks or as an integral part of the controller 330. If possible, the angle increment signal generated by the incremental encoder 180 or the electrical signal converted therefrom can be fed to the QEP evaluation units without prior duplication.

The QEP evaluation units 320-1 and 320-2 can be programmed with such a clock frequency that they output the time T _event between two or any number of increments as a signal and / or output the current angular position, for example as an angle link, and / or output the direction of rotation. For this purpose, a QEP evaluation unit is typically programmed with a clock frequency and then provides a data stream of angle increment information corresponding to the programming, which is then read out by the controller during operation, ie, to be sampled.

The data streams provided by the QEP evaluators 320-1 and 320-2 are then read from a controller 330, which typically includes a processor 360, and further processed as described below. In this case, the angle increment signals generated by the incremental encoder 180 are respectively transmitted to the QEP evaluation units 320-1 and 320-2. The controller 330 is electrically connected to and controls the motor 170 via the line 340. On the one hand, the controller 330 thus controls the motor 170, on the other hand, the controller 330 receives information about the increment Signal generator 310 and the two QEP evaluation 320-1, 320-2 information about the driven motor 170. The controller itself can be configured as a digital circuit, ie a so-called CPU (Central Processing Unit) and corresponding peripheral circuit elements, such as D / A and / or A / D for signal conversion, as well as power semiconductors for generating the control signals for the motor have.

The first QEP evaluation unit, that is to say 320-1, is set up at a first clock frequency in such a way that it determines the time interval between a zeroth and an Nth angle increment and makes it available as a data stream to the controller 330, wherein N increases is equal to 2, so that the QEP evaluation unit 320-1 determines the time for sweeping a number N increments, where N> 2. Thus, the first QEP evaluation unit 320-1 does not signal the time interval between two successive, ie adjacent, angular increments, but the distance between N> 2 successive angle increments.

The second QEP evaluation unit, ie 320-2, is set up with a clock frequency such that it generates a data stream with the time interval between two directly successive angle increments, ie signals the time interval between two signal edges of the tracks A and B. The second QEP evaluation unit 320-2 thus transmits the ascertained angle increment information to the control in shorter time intervals than the first QEP evaluation unit 320-1. Alternatively, the QEP evaluation units can each signal the time intervals of two different numbers of increments, wherein the numbers N can each be greater than 2. During operation of the traversing unit, the controller 330 determines the rotational speed or angular velocity ω according to one of the equations described above. Further, the controller 330 determines the position of the thread guide 120 as described above from the number of the over-directed angle increments with respect to a reference position. The angle increment information of the first QEP evaluation unit 320-1 is used as the basis for the calculation of these values if the angular velocity of the drive shaft 171 of the motor 170 exceeds a threshold value of the angular velocity. For this purpose, the data streams of the QEP evaluation units 320-1 and 320.2 are supplied to a data stream coupler 350 within the controller 330, which selects the data streams of the two QEP evaluation units 320-1 and 320-2 in dependence on the threshold value of the angular velocity and one of the Data streams for controlling the engine releases. The controller 330 thus processes the data stream of the first QEP evaluation unit 320-1 only when the signals transmitted by the first QEP evaluation unit 320-1 exceed a first predetermined threshold value of the angular velocity, ie the yarn guide 120 with relatively high angular velocity of the drive shaft 171 is moved. On the one hand, this ensures that sufficient time remains for the processing of these values before the next value has to be processed. On the other hand, the relative error for time intervals, which are determined over several angular increments, smaller than for intervals, which is over a single or a few angle increments are determined. The data stream provided by the second QEP evaluation unit 320-2 is ignored during the time in which the data stream of the first QEP evaluation unit 320-1 is processed. This condition essentially lies in the linear movement range of the thread guide 120 between the origin points. In this area, the yarn guide 120 is guided by the motor 170 at a uniformly high guide speed, so that the drive shaft 171 rotates at a relatively high angular velocity.

Although modern stepper motors or servomotors react very quickly to control signals, the motor requires a change of direction, a so-called reversion process, at the end of the traversing movement, ie when the thread guide reaches one end of its running distance, the direction of movement changes and then in the opposite direction is running, a finite time.

Accordingly, the controller 330 controls the motor 170 at the end of the traversing motion so that the rotational speed of the motor 170 is reduced until the direction of rotation reversal. The yarn guide 120 is accordingly decelerated at the end of the traverse stroke and then moved in the opposite direction. Accordingly, while decreasing the angular velocity of the drive shaft 171, the time intervals between the data supplies of the QEP evaluators 320-1 and 320-2 become larger. In this phase, the data stream coupler 350 checks the data streams read out / sampled by the QEP evaluation units 320-1 and 320-2 as to whether they exceed or fall below a predefined threshold value of the angular velocity. Gege- if appropriate, ie if the event time exceeds a threshold time, the controller reads from then on the higher-resolution data stream of the second QEP evaluation 320-2 and processes it. Although this angular increment information has a larger relative error, the update rate is greater because the second QEP evaluator 320- 2 provides higher resolution signals. As the angular velocity of the drive shaft decreases, the values of the event times increase and the relative error decreases. In the phase of relatively low angular velocities of the drive shaft 171, which occur in the Umkehrberei- Chen the yarn guide 120 at the traverse ends, thus the data flow of the angle information of the second QEP evaluation 320-2 is released from the data stream coupler 360 for the control of the motor 170. After the direction of rotation of the drive shaft 171 has been reversed, that is, the yarn guide 120 is also moved in the opposite direction, the controller 300 controls the motor 170 in such a way that it accelerates its rotational movement again as quickly as possible to a maximum value. Accordingly, the time intervals signaled by the QEP evaluation units 320-1 and 320-2 as well as the time intervals of the signaling itself become smaller. In this case, the controller ignores the data stream of the first QEP evaluation unit 320-1, but instead processes the data stream supplied by the second QEP evaluation unit 320-2, as long as the signals supplied by the second QEP evaluation unit 320-2 have a second predetermined threshold value Do not exceed angular velocity. As soon as the data stream coupler 350 of the controller 300 detects this overshoot, the data stream of the second QEP evaluation unit 320-2 is ignored and only the data stream provided by the first QEP evaluation unit 302 - 1 is used to control the motor 170.

In this way, the controller of the traversing unit processes only the data streams of the first QEP evaluation unit 302-1 when the drive shaft 171 of the motor 170 rotates rapidly. However, if the data stream coupler 350 recognizes to the controller 330 that the motor 170 is rotating at low angular velocity, ie, the time intervals between increments are large, the controller 330 processes the data streams of the second QEP evaluation unit 302-1, which measure the angular increments at smaller time intervals provides.

The first predetermined threshold value of the angular velocity may be equal to the second predetermined threshold value of the angular velocity. Alternatively, the two threshold values can be unequal. In particular, the first predetermined threshold value may be smaller than the second predetermined threshold value, so that a hysteresis curve is run through. The evaluation of the data streams provided by the second QEP evaluation unit 320-2, ie the finely graduated signals, causes finer graduated signals with a higher update rate to be evaluated around the reversing point of the yarn guide 120, ie when the motor changes direction the controller will be provided. On the other hand, at high angular velocity of the drive shaft 171 of the motor 170, coarse resolved data streams of angular increment information are processed, thereby ensuring that the output of the drive shaft 171 of the motor 170 is equal. sufficient time or computing power is available for processing all signals intended for processing and signals with a small relative error are processed.

The described traversing unit as well as the method for controlling the traversing unit thus enable a more exact control of the thread guide, which allows a more accurate filing of the thread on the spool.

Claims

claims

A traversing unit for guiding a thread by means of a thread guide (120) comprising a motor (170) having a drive shaft (1 1) for driving the thread guide (120), a controller (330) coupled to the motor (170) and a drive shaft (15). 171) of the motor (170) coupled incremental encoder (180) which is connected to the controller,

characterized in that

the controller (330) has a first QEP evaluation unit (320-1) for generating a first data stream and a second QEP evaluation unit (320-2) for simultaneously generating a second data stream.

Traversing unit according to claim 1,

characterized in that

the first QEP evaluator (320-1) is programmed with a first high angular velocity clock frequency of the drive shaft (171), and the second QEP evaluator (320-2) is programmed with a second low angular velocity clock frequency of the drive shaft (171) ,

Chnagiereinheit according to claim 2,

characterized in that

the first clock frequency of the first QEP evaluation unit (320-1) for generating a clock for an interval of a number of N, N greater than 2, is determined by angle increments and that the second Clock frequency of the second QEP evaluation unit (320-1) is determined to generate a clock for each separate angle increment.

Traversing unit according to one of claims 1 to 3,

characterized in that

the controller (300) has a data stream coupler (350) which is connected to the QEP evaluation units (320-1; 320-2) and which, depending on a predetermined angular velocity, transmits one of the data streams of the QEP evaluation units (320-1; 2) for controlling the motor (170) releases.

Traversing unit according to one of claims 1 to 4,

characterized in that

a signal conditioning unit (310) is arranged between the incremental encoder (180) and the QEP evaluation units (320-1; 320-2), by means of which a doubling of an angular increment signal of the incremental encoder (180) can be generated.

Traversing unit according to claim 5,

characterized in that

the signal conditioning unit (310) comprises an optocoupler (350) for transmitting the doubled angular increment signals.

Traversing unit according to claim 1,

characterized in that

the drive shaft (171) by means of a drive wheel (140) drives a belt (130) which is coupled to the yarn guide (120).

8. A method for controlling a traversing unit for guiding a thread by means of a thread guide, wherein the traversing unit comprises a motor with a drive shaft for driving the thread guide, an incremental encoder for detecting a Winkelinkrements of

Drive shaft and coupled to the engine control, comprising the steps of:

Determination of angle increment signals of the angle increments swept by the drive shaft,

Generation of two separate data streams from

Angular increment information from the angle increment signals, and determining an angular velocity of the drive shaft from one of the data streams to control the motor.

Method according to claim 8,

with the further steps

Generating the first data stream at a clock frequency at which a clock is detected for an interval of a number of N, N 2, angle increments, and

simultaneously generating the second data stream at a clock frequency with which a clock is detected for each separate angle increment.

10. The method according to claim 9,

characterized in that s

when a predefined angular speed is exceeded, the motor is based on the first data stream and falls below the predefined angular velocity of the motor is controlled based on the second data stream.

Method according to one of claims 8 to 10,

characterized in that

the increment angle signals of the incremental encoder are doubled before generating the data streams.

Method according to claim 11,

characterized in that

the angle increment signals of the incremental encoder are transmitted opto-electronically with a galvanic current circuit separation.

Method according to claim 8,

characterized in that

the drive shaft of the motor by means of a drive wheel drives a belt which is coupled to the yarn guide.