WO2011015178A1

WO2011015178A1 - Method and device for monitoring the thread arrival during the weft insertion of different weft threads on a weaving machine

Info

Publication number: WO2011015178A1
Application number: PCT/DE2010/000867
Authority: WO
Inventors: Dieter Teufel
Original assignee: Lindauer Dornier Gesellschaft Mbh
Priority date: 2009-08-03
Filing date: 2010-07-24
Publication date: 2011-02-10
Also published as: JP5575898B2; CN102471959A; JP2013501160A; EP2462268A1; CN102471959B; DE102009035904A1; EP2462268B1

Abstract

On a weaving machine, the arrival of the weft thread (1) during insertion into a shed is monitored by means of a sensor (4) at the end of the insertion path (5). The sensor (4) produces different signal profiles (6) upon the passage of different weft threads (1,2,3...n). A control unit (7) determines the respective reference signal from several signal profiles (6) of the sensor (4) for each weft thread (1,2,3...n) to be inserted depending on the weaving pattern, the reference signal being compared with the actual signal profile (6) in the weaving process. The operator no longer has to make any entries into the controller (7) regarding the type of weft threads (1) to be monitored during weft insertion.

Description

Method and device for monitoring the thread arrival during weft insertion of different weft threads on one

Weaving machine The present invention relates to a method and a device for

Monitoring the yarn arrival of weft yarns on a loom during the weaving pattern dependent entry of different weft yarns into a shed.

In weaving machines monitoring of weft threads during the weft insertion are known in the prior art.

Such a device is shown for example in EP 0 374 398 B1. This relates to a weft thread monitor for air-jet looms with a weft insertion of threads of different quality, wherein the threads are deducted from the respective yarn store and entered via an air entry control controlled main and Stafettendüsen in the air duct of a Profilriets and thus in a shed. On the output side of the Profilriets the weft detector is arranged with sensors whose electrical signals are fed to the input of an amplifier and then the air intake control and evaluated there. Depending on the result of the evaluation, the entry process is continued or interrupted and an error message is output. At each weft insertion or monitoring process is the amplifier of the

Weft detector of the air intake control supplied an electrical signal, which is determined by the mechanical and air-effective properties of each weft thread. The amplifier is designed such that, depending on the characteristics of the weft threads, it amplifies the electrical output signal of the sensor before it is fed to the air intake control for evaluation. At the Lufteintragssteuerung programming is provided, with which the mechanical and air-effective properties of the weft threads for the weave or the shot sequence detected, processed, stored and supplied in the form of electrical correction signals weaving pattern depending on the amplifier.

This correction of the output signals that the sensor sends to the air intake control via the amplifier is useful in order to avoid weaving errors. In this way, the system sensor / amplifier can be informed in a forward-looking manner, which signal strength at the next weft insertion depending on the

Characteristics of the weft yarn is to be expected and how the signal amplification is to be made so that the evaluation unit of the air intake control detects whether the weft yarn arrived at the exit side - i. correctly registered or not.

By such adaptation to the respective weft yarn weave errors can be avoided, which arise, for example, that fiber fly a

Sensor signal (= thread available) triggers, although the weft thread itself is not registered properly, that is, arrived at the firing monitor or sensor. However, the web pattern-dependent weft properties must first be communicated to the system by the operator. The programming unit of the Lufteintragssteuerung determined from the appropriate correction signals for the amplifier. The manner in which a separate detection of the different types of weft threads by the system sensor / amplifier air entry control of the loom is to take place is not disclosed.

EP 1 445 365 B1 describes a method for monitoring weft threads on a weaving machine during the weaving pattern-dependent entry

different weft threads in a shed, each to be entered

Weft at the end of the weft insertion path of one or two sensors is monitored, which detects at certain times whether a weft thread is present or not. In this case, outside the period in which the passage of a weft thread is monitored by the sensor, a reference threshold value and a gain factor are calculated from the sensor signal by means of an electronic control unit. This calculation takes place at certain times, which are specified via inputs of the operator with regard to the properties of the weft thread to be respectively entered in accordance with the weaving pattern. This is the case when comparing the signal actually generated when the weft thread passes through the sensor with the reference threshold value

various additional conditions. These additional conditions are also predetermined by the operator, depending on the type of each weft to be entered weft. Object of the present invention is to provide a method and an apparatus, with the various for the supervision of the yarn arrival of the

Weft yarn crucial properties of different weaving weft threads to be entered weft insertion during weft insertion on a weaving machine by the system "sensor / control unit weaving machine" are independently detected.Thus, an optimal adaptation of the monitoring process to different types of weft threads and thus avoidance of

Weaving or Fehlangestellungen on the weaving machine can be made possible without the operator to make inputs regarding the properties of the weft threads in the control unit of the loom.

The object is achieved by a method and a device according to the

solved independent claims. A method for monitoring the yarn arrival of weft threads on a loom during the web pattern-dependent entry of different weft threads in a shed provides the monitoring of a weft to be inserted in the region of the end of the weft insertion path by at least one opto-electronic sensor.

In this case, depending on various decisive for the monitoring of the weft yarn properties of the weft thread in the passage of

Weft threads with different such properties generated by the sensor different electrical waveforms.

These waveforms are evaluated by at least one electronic control unit.

According to the invention by means of the control unit for each weaving pattern to be entered weft from several by weft insertion at the

Weaving machine generated during the passage of the respective weft thread by the sensor generated waveforms for each weaving pattern to be entered weft typical reference signal and stored. For this purpose, the fact is used that sensor elements that are usually used to monitor weft yarns on weaving machines, when passing eg a thin weft yarn provide a different output signal than when passing through a thick weft thread. When weaving pattern dependent

Weft insertion of weft threads e.g. different thickness results therefore for each weft insertion in the weave a characteristic waveform at the output of the sensor. For different types of weft threads, however, other properties of the weft threads can be the cause of different

Waveforms during the passage of a weft thread through the sensor to be. A smooth weft without fibers will produce different waveforms than a hairy weft - even if they have the same thread size.

For monitoring the weft thread, sensors with different technologies can be used within the scope of the invention, as far as they generate signal traces as the weft thread passes through the sensor, which are different for different types and different behavior of weft threads.

These may be, for example, opto-electrical sensors in which one or more light beams are emitted by at least one transmitter and the light is detected by one or more receivers, as long as the light beam is not or only partially e.g. interrupted by a weft thread. Such sensors are often housed today with its own electronics unit within a common housing. This electronic unit controls e.g. the light signal and prepares the signals generated by the light receiver for further processing in the electronic control unit of the loom. It may also be necessary to send signals to the electronics unit of the sensor from the loom control unit. In the context of the invention is meant by "sensor" an assembly which - depending on the type of sensor - and an electronic unit of the here

may include described type. By "waveform" of the sensor is thus meant the course of the signal, which is generated either by the sensor directly or by the associated with this own electronic unit.

However, it is also possible to use sensors in which the light emitted by at least one transmitter reflects off obstacles in the region of the light beam and detected by one or more receivers arranged to receive reflected light from the receivers and convert the light intensity and / or the position into an electrical signal. Depending on the type of sensor, different positions of the weft thread passing through the sensor in the region of the sensor can also generate different signal profiles that can be evaluated by the control unit. This means that with these sensors, the behavior of the weft thread in determining the

Waveforms is taken into account.

The sensor is usually mounted at the end of the weft insertion path.

Often it makes sense to have one or more other sensors - in terms of

Weft insertion direction - further back, away from the first sensor

to arrange. Thus, e.g. be determined in an air-jet weaving machine, whether a weft thread portion, which has been recognized correctly by the first sensor, not previously torn already during the weft insertion. The arrival of a weft thread or weft thread section in such a second sensor can also be monitored by the method according to the invention.

The sensors referred to here are thus in the area of the

Weft insertion path positioned.

The analog electrical waveforms of the sensors, of which

According to the invention are characterized by different signal levels and different times at which the signals are generated by the sensor.

With electronic control unit here is the totality of all hardware and

Software elements that receive electrical signals within the loom, process and forward to weaving machine components or display units. Depending on the embodiment of the sensor of this, if necessary, to distinguish the above-described own electronic unit of the sensor, but which may also be integrated into the control unit. According to the invention, for a weaving cycle, the actual signal course which is generated by the sensor when a weft thread passes through is electronically compared by means of the control unit with the stored reference signal of the weft thread to be introduced in this weaving cycle as a function of the weaving pattern.

In general, the reference signal consists of a single signal value (e.g., an average value) that is electronically compared at a particular time during the weaving cycle with the actual waveform by the control unit.

As described above, in order to calculate the reference signal for a weft thread to be introduced in a weaving pattern, according to the invention, a plurality of weft inserts on the weaving machine during passage of the respective weft thread

Weft thread generated by the sensor signal curves at least one typical for the weaving pattern to be entered weft thread typical reference signal calculated and stored.

For this calculation, but also for the comparison in the current weaving cycle, the actual signal curve can still be processed, that is to say electronically amplified, integrated, averaged or otherwise suitably changed for the evaluation and the electronic comparison in a manner known per se. However, it is also conceivable, instead of a single signal value, to store a reference signal in the form of a signal curve and to compare it with an actual analogue signal characteristic prepared for the evaluation and the comparison at specific times. Such methods for comparing different waveforms are known in the art. According to the invention, the signal curves are taken into account, which are generated by the sensor during the passage of the weft thread.

Using the method with respect to the signals of another sensor, e.g. To detect a torn thread end, the determination of the

In principle, reference signals also take place from the signal curves of the first sensor. However, it is also possible to use those gradients that the second sensor generates in the event of a fault - weft thread being torn off during entry. The evaluation of the signals in the electronic control unit for the purpose of monitoring the yarn arrival of the weft thread can take into account not only the comparison of the signal characteristics of the sensor but also further electrical signal values present in the control. However, signal values due to operator input regarding the various weft threads to be monitored are not required.

In a preferred embodiment, depending on the result of the evaluation, the electronic control unit outputs at least one of a plurality of possible signals. Preferably, at least one signal for WM stop is output when the

Evaluation of the signals by the controller reveals that the weft thread has not arrived or broken in the area of the end of the shed. The web process is interrupted; It makes sense to output an error message to the operator. This output is e.g. to various components involved in the web process. These may be, for example, the main drive, the feeder or the weft insertion components. A signal output to the possibly existing electronic unit of the sensor is feasible if necessary.

In a further embodiment of the invention, the evaluation is used in a learning phase of the weaving machine to calculate first reference signals without error messages are already brought about with stop the weaving machine, if the comparison between the actual signal and the reference signal negative. The control unit works in a so-called learning phase. This is e.g. useful when weaving new fabric patterns with changed weft threads to be entered in accordance with weaving patterns.

It is also conceivable, of course, already determined in earlier production runs

Download reference signals for each weaving pattern-dependent weft with the entire tissue and pattern data of a particular tissue from an external medium. Then the learning phase can be omitted.

In a further embodiment of the invention, the calculation of the

Reference signal during the ongoing weaving operation by means of the control unit regularly repeated and adapted to the current characteristics of each weaving pattern to be entered weft thread. A device according to the present invention comprises at least one sensor in the region of the entry path for monitoring the thread arrival when various weft threads are introduced into the shed of a weaving machine.

The sensor is of the type required for the method according to the invention as described above. That is, sensors are used which generate signals as the weft passes through the sensor for various types and / or different behavior of weft yarns

are different. These are predominantly opto-electrical sensor principles that generate waveforms either by interrupting light beams or by their reflection at obstacles.

These are sensors or even sensor-electronic assemblies - so-called firing monitors - with which analog electrical signal waveforms are generated, which are characterized by different signal levels at different times.

The sensor or sensors are usually mounted at the end of the entry path.

Furthermore, a control device is provided, which is connected signal transmitting with one or more sensors. The control device comprises elements that enable the entry of different weft threads depending on the weave pattern.

The control device is signal-transmitting connected to other important for the weaving process components of a loom; for example with the main drive and the components of the weft insertion.

Furthermore, display devices can be provided which make messages of the control device visible to the operator.

According to the invention, the control unit with such hardware and software

equipped so that the inventive method described above is feasible. For this purpose, electronic modules or software modules are provided, which allow a storage of signal waveforms, averaging and the comparison of individual signals or entire signal waveforms. The extent to which hardware and / or software is used here remains up to the person skilled in the art to whom such components or software modules are known in principle. In this case, an embodiment is preferred in which various signals can be output in the control unit as a function of the evaluation of the signal profiles of the sensors. In particular, the output of a signal for WM stop is feasible here, so that the weaving machine can be stopped when the sensor and control unit recognize that the signal in the current weave cycle from the reference signal inadmissible. The latter usually means that a weft thread was not entered properly.

In one embodiment of the invention are on the device

Input options are available with which the operator can specify a learning phase during which the first reference signals are determined.

In a further embodiment, input possibilities are provided by means of which the operator can specify the number of weaving machine looms which should underlie the calculation of the reference signal for each weft thread to be entered in dependence on the weaving pattern.

Figure 1 Schematic representation of an embodiment of

Device according to the invention for carrying out the method

FIG. 2 shows exemplary signal curves at the output of a sensor

during the implementation of the method according to the invention

FIG. 1 shows an embodiment of the device according to the invention.

Shown is an example of the weft insertion on an air-jet weaving machine.

However, the device according to the invention is also in weaving machines with other entry principles - e.g. Water jet machines - used in which the

Monitoring the thread arrival is made by a sensor at the end of the entry path.

A weft thread 1 is made up of a number of weft threads 1, 2, 3... N

web pattern dependent selected, withdrawn from supply reels by means of prewinders 9 and entered, for example by main nozzles 10 and auxiliary nozzles 13 in the channel of a Profilriets 12. The profile sheet 12 is in the range of warp threads, not shown, which form a shed. The weft insertion path 5 extends in in this case, from the main nozzles 10 across the width of the shed to the outermost position taken by the front weft end

Weft insertion can take.

The arrival of the weft 1 at the end of the weft insertion path 5 is monitored by one or more sensors 4 located in the region of the end of the weft insertion path.

The sensor 4, which may also contain its own, not shown, electronics, generates a waveform 6, which is passed on to an electronic control unit 7 on. In the control unit 7, the signal profile 6 is evaluated with the method according to the invention described above.

Depending on the result of the evaluation, the control unit 7 optionally outputs a signal 11 to various weaving machine components 8, 9, 10, 13. If necessary, a signal can also be returned to the sensor 4 or to the electronics connected to the sensor.

Figure 2 shows measured waveforms 6.1, 6.2, 6.3 6.n at the output of a

Sensor 4 for monitoring the yarn arrival of weft yarns 1, 2, 3 ... n during several weaving cycles of a loom.

For each web pattern-dependent entry cycle of a weft thread 1, 2, 3 ... n into the shed results in another typical course of the signal 6, which generates the sensor 4, when the weft thread 1 passes through the region of the sensor. When using similar weft threads in successive weaving cycles, the waveforms will differ less or not at all.

FIG. 2 shows several of these passage processes with their respectively typical signal progressions 6.1, 6.2, 6.3, 6.n in chronological order of several

depending on the weaving pattern of different weft threads 1, 2, 3 ... n.

In the present case, the behavior is shown by way of example on an air-jet loom, in which an opto-electronic sensor 4 is arranged at the exit of the channel of a profile reed 12.

Each individual signal course 6.1, 6.2, 6.3... 6.n indicates the arrival of the respective weft thread 1, 2, 3... N at the end of the entry path and thus the successful weft insertion. If the weft insertion is incorrect, the relevant signal is missing. The undesirable, but unavoidable entry of fiber dust or fluff results in a signal curve 6, which depends on the one for the weave pattern weft thread typical signal waveform deviates - either in height and / or in terms of the timing of the signal. This is detected in the evaluation of the waveforms 6 with the aid of the inventively determined reference signal and the process is interpreted by the control unit 7 as improper weft insertion.

Reference numeral list

1, 2, 3 ... n weft thread

4 sensor

5 weft insertion path

6 Signal curve of the sensor

7 electronic control unit

8 main drive

9 thread store

10 main nozzles for weft threads 1, 2,3 ... n

11 one of various possible signals

12 profile rat '

13 auxiliary nozzles

Claims

claims

1. A method for monitoring the Fadenankunft different weft threads (1, 2, 3 ... n) when web-pattern-dependent entry in the shed a

Weaving machine, wherein a registered weft thread (1) by an optoelectronic sensor (4) in the region of the end of the entry path (5) is monitored, depending on various for the monitoring of the weft thread (1) decisive properties and / or depending on the behavior of the

Weft thread (1) when passing through the sensor (4) produces different electrical signal waveforms (6.1, 6.2, 6.3 6.n), of at least one

electronic control unit (7) are evaluated,

characterized by the following method steps

an electrical signal course (6), which is characterized by different signal levels and different times at which the signals from the sensor (4) during weft insertion of the respective weft thread (1) are generated, is evaluated in the control unit (7) and

Further, likewise marked electrical signal curves (6), which are generated in further weft entries of the respective weft thread (1) are evaluated in the control unit (7) and

From a plurality of signal curves (6) generated by weft insertion, at least one reference signal typical for the weft thread (1, 2, 3... n) is calculated and stored, and

Within a weaving cycle of the weaving machine, the actual signal course (6) which is generated by the sensor (4) when a weft thread (1) passes through the control unit (7) with the at least one stored reference signal of weaving pattern dependent in this weaving cycle to be entered weft thread (1, 2,3 ... n) compared electronically.

2. The method according to claim 1, characterized in that

the reference signal is calculated and stored in the form of a signal waveform.

3. The method according to claim 1 or 2, characterized in that

the control unit (7) outputs at least one of various possible signals (11) as a function of the result of the evaluation, a possible signal (11) being the signal for WM stop.

4. The method according to claim 3, characterized in that

during a predetermined learning phase of the loom, a stop signal (11) generated on the basis of the evaluation is not forwarded to the weaving machine components (8, 9, 10, 13) involved in the weaving process.

5. The method according to any one of claims 1 to 4, characterized in that the calculation of the reference signal for each weave pattern dependent

to be entered weft thread (1, 2,3 ... n) during the current weaving operation by the controller (7) regularly repeated and thus the reference signal is updated continuously.

6. The method according to any one of claims 1 or 5, characterized in that for each weaving pattern to be entered weft thread (1, 2,3 ... n) will specify the number of weaving cycles, the calculation of the reference signal for this weft thread (1 , 2,3 ... n) is the basis.

7. Device for monitoring the yarn arrival of various weft threads (1, 2.3 ... n) when web pattern-dependent entry in the shed of a loom, with at least one in the region of the end of the entry path (5) mounted opto-electronic sensor (4) the way that depending on various for the monitoring of the weft thread (1) decisive properties and / or the behavior of the weft thread (1) when passing through the sensor (4) different electrical signal waveforms (6.1, 6.2, 6.3 6.n) are generated and with an electronic control unit (7) with controls that

depending on weaving pattern the entry of different weft threads (1, 2,3 ... n)

permit and the signal transmitting so connected to the at least one sensor (4), that the control unit (7) is able to evaluate the signal waveforms (6) of the sensor, characterized in that

the control unit (7) is equipped with such hardware and software that Weft threads (1, 2, 3,... n) to be inserted in dependence on weaving pattern from a plurality of signal progressions (6) generated by weft insertion on the weaving machine as the respective weft thread (1) passes through the sensor (4), characterized by different signal heights and different times are, for the respective weft thread (1, 2,3 ... n) typical reference signal in the form of a

Waveform can be calculated and stored and

for a weaving cycle, the actual signal course (6) produced by the sensor (4) when a weft thread (1) passes through the control unit (7) with the stored reference signal of the weft thread (1, 2,3 ... n) is electronically comparable.

8. Apparatus according to claim 7, characterized in that

by the control unit (7) depending on the result of the evaluation of at least one of different possible signals (11) can be output, wherein a possible signal (11) is the signal for WM stop.

9. Apparatus according to claim 8, characterized in that

the electronic control unit (7) has input means by means of which the operator can specify a learning phase of the weaving machine during which a WM stop signal (11) generated on the basis of the comparison is not output.

10. Device according to one of claims 7-9, characterized in that by means of the electronic control unit (7), the calculation of the reference signal for each weaving pattern to be entered weft yarn (1, 2,3 ... n) regularly repeatable while the weaving operation and so that the reference signal is continuously updatable.

11. Apparatus according to claim 7 or 10, characterized in that

the control unit (7) has means by which the operator can count the number of

Web cycles of the weaving machine can pretend that the calculation of the reference signal for each weaving pattern to be entered weft thread (1, 2,3 ... n) should be based.