EP1928774A1

EP1928774A1 - Method for operating a workstation of a textile machine that produces crosswound bobbins

Info

Publication number: EP1928774A1
Application number: EP06791900A
Authority: EP
Inventors: Michael Iding
Original assignee: Oerlikon Textile GmbH and Co KG
Current assignee: Oerlikon Textile GmbH and Co KG
Priority date: 2005-09-24
Filing date: 2006-09-07
Publication date: 2008-06-11
Anticipated expiration: 2026-09-07
Also published as: DE102005045789A1; EP1928774B1; CN101268001A; CN101268001B; JP2009508783A; JP5124465B2; DE502006005879D1; WO2007033771A1

Abstract

The invention relates to a method for operating a workstation of a textile machine that produces crosswound bobbins. Said station comprises a bobbin drive, whose speed can be regulated in order to adjust the winding speed of the crosswound bobbin, a thread tensile force sensor, which is connected to a workstation computer, for monitoring the thread tensile force of a thread that is supplied from a feed bobbin and a thread tensioner for regulating the thread tensile force. According to the invention, a value for a desired thread tensile force (FZKSoll) and a value (TG) for a permitted proportional deviation from the desired thread tensile force (FZKSoll) can be entered into the workstation computer (32). The workstation computer (32) can instantly suspend the winding process and trigger an alarm if the permitted proportional deviation from the desired tensile force (FZKSoll) is exceeded.

Description

description

Method for operating a workstation of a textile machine producing cross-wound bobbins

The invention relates to a method for operating a workstation of a cross-wound textile machine according to the preamble of claim 1.

Textile machines producing cross-wound bobbins, for example automatic packages, have been known for a long time.

Such spoolers usually have a plurality of juxtaposed in series, similar jobs, each having different Fadenhandhabungs- or thread monitoring devices.

The control and monitoring of these thread handling or thread monitoring devices takes place in each case via a workstation computer, wherein the individual workstation computers, usually via a machine bus, are also connected to a central control unit of the cheese winder.

The supply and disposal of the jobs of the automatic cheese winder with yarn material, for example via a bobbin and tube transport system.

In the bobbin and tube transport system, feed bobbins, usually spinning cops, or empty tubes, run on transport plates.

Instead of a coil and sleeve transport system, such

Textile machines but also work-own Spinnkopsmagazine have.

Such work-own Spinnkopsmagazine are then preferably designed as a so-called round magazines, which are manually populated by the operator. Furthermore, such automatic packages can have a service unit which automatically supplies the workstations.

Such a service unit, such as a so-called cheese changer, takes the finished cheeses from the creel of jobs, transferred them to a machine-length transport device, which conveys the cheeses to a machine end side transfer station, and changes a new empty tube in the creel of the work in question.

During the rewinding of the yarn from the small-volume spinning cops to a much more yarn having cross-wound bobbin, the thread is scanned for thread defects, whereby detected errors are eliminated.

The running thread is also monitored during rewinding by a yarn tension sensor and held the yarn tension by means of a thread tensioner at a predetermined level. That is, by means of the thread tensioner, a substantially constant yarn tension of the running yarn is set to ensure in this way a uniform winding of the yarn on the cross-wound bobbin.

Fadenzugkraftsensoren which detect the current yarn tension of a running yarn are known for example from DE 41 29 803 Al.

The yarn tensile force sensor performs a yarn tension measurement on the running yarn and provides a control signal for a yarn tensioner which, in accordance with the control signal, exerts a more or less large braking effect on the running yarn. Such thread tensioner, which are described for example in DE 41 30 301 Al, have for this purpose acted upon with a variable pressure force yarn braking device. Through the interaction of the yarn tension sensor with the thread tensioner is largely ensured that the yarn is wound with a defined yarn tension on the package. That is, when the yarn tension sensor signals an increase in yarn tension, the yarn tensioner is slightly opened to compensate for the increase in yarn tension.

Accordingly, the thread tensioner is slightly closed when the yarn tension sensor signals a drop in the yarn tension.

However, during operation of a cross-spooling machine, critical operating conditions may also occur in which the above-described interplay of yarn tension sensor and thread tensioner no longer functions properly.

If, for example, as described in DE 198 48 881 Al, in connection with the cleaning of a yarn defect, in particular after the splicing process to a Fadenverhakung the spinning cop, the yarn tension of a thread can rise sharply, although the thread tensioner is open. According to DE 198 48 881 Al, such Fadenverhakung is detected and eliminated by detecting the occurring yarn tension by means of the yarn tension sensor after connecting the upper thread with the lower thread and the determined value is processed in the workstation computer to the effect that when exceeding a limit on a Fadenverhakung closed and then the Ablaufspulenwechseleinrichtung the relevant job in terms of 'bobbin change' is pressed.

Another, critical operating condition is given, for example, when the thread in the region of the thread tensioner does not run between the brake plates, that is, when the thread is passed beside, in front of or behind the brake plates.

Since the rewinding is not directly affected by this, this misalignment of the thread is not always immediately recognizable.

Due to the lack of regulation of the thread tension, however, a faulty, generally too soft wound package can occur. In order to avoid this operating state, DE 199 05 860 A1 describes a method in which the workstation calculates the contact pressure of the thread tensioner according to a thread tension determined by the thread tension sensor, compares this predetermined contact pressure with a predetermined limit value for the contact pressure, and if the limit value for a predetermined period of time is reached or exceeded, the winding process interrupts.

Also in the production of dye packages, which are known to be spooled with a very low yarn tension, it may happen that the thread tensioner is already completely open and the yarn tension is still above a desired value.

In such a case, although the workstation computer ensures that the winding speed and thus also the thread tension are reduced at the workstation in question, since the system operates relatively sluggishly, it is not always and above all not always ensured that the thread tension is always sufficient the desired value is adjusted.

The consequence of such a critical operating condition are generally poor quality spools, the inferior quality of these cheeses is often not immediately recognizable.

Based on jobs of the aforementioned type and method for their operation, the invention has the object to develop a method by which a high winding quality of cheeses, especially of dye packages, can be reliably ensured.

This object is achieved by a method having the features described in claim 1.

Advantageous embodiments of the invention are the subject of the dependent claims. The fact that the value of the desired yarn tension as well as the value for a permitted percentage deviation can be entered into the workstation computer, the compliance of these values is monitored online by the workstation computer and if an unauthorized deviation immediately intervenes automatically in the winding process and alarm is triggered, is ensured that only cheeses are produced in which the yarn tension during the entire winding process is within permitted tolerance limits.

Generating an alarm also indicates that there is an irregularity in the job in question and a job verification is advised.

As described in claim 2, it is also provided in an advantageous embodiment that the time period in which there may be an unauthorized over or under the thread tension, before the winding process is interrupted and an alarm is triggered, is adjustable on the workstation. That is, the operator can, for example, depending on the yarn material or the subsequent use of the cheese, individually set how fast the workstation computer should respond to detected, outside predetermined tolerance limits deviations of the thread tension.

As described in claim 3, the adjustable reaction time of the system is between 0.1 second and 5 seconds. In practical experiments, a reaction time of about 1 second has been found to be particularly advantageous.

As set out in claim 4, when the yarn tension has reached or exceeded the tolerance limits for the predetermined period of time, the workstation computer initiates a controlled thread cut.

By such a thread cutting the winding process is interrupted immediately and thus in a simple manner Prevents the production of a cheese whose thread layers are sometimes too hard or too soft.

In addition, as described in claim 5, also triggered an alarm and thus the operating personnel are made aware of the incorrectly working job.

The invention will be explained in more detail with reference to an embodiment shown in the drawings.

Show it:

FIG. 1 shows a side view of a workstation of a textile machine producing cross-wound bobbins,

Figure 2 is a schematic representation of the workstation of a winding unit, which is in communication with a yarn tension sensor, a thread tensioner, a thread cutting device and an alarm device.

FIG. 1 shows a side view of a workstation 10 of a textile machine 1 producing cross-wound bobbins. Textile machines known for cross-winding machines have a multiplicity of workstations 10 arranged side by side on which bobbins 12, preferably spinning cops, are wound into large-size cheeses 14.

The spinning cops 12 arrive via a transport device 16 to the individual workstations 10, which, as known per se, includes a plurality of unspecified transport routes on which, plugged on transport plates 20, spin cops 12 and empty tubes 18 are transported. As indicated in Fig. 1, a yarn 22 is withdrawn from a arranged in a winding position I spinning head 12, the first on its way to the cheese 14, a lower thread sensor 28, the via a signal line 30 is connected to a workstation computer 32 happens.

By means of this lower thread sensor 28 is, for example, after a

Thread break or a controlled thread cut, before

Introduction of the upper thread search, determined if at all

Bobbin thread 34 is present.

Above the lower thread sensor 28, a thread tensioner 36 is arranged, which, as indicated in Figure 2, two brake plates 5,

6, which exert on the current thread 22 a contact pressure.

The thread tensioner 36 is also connected via a control line 38 to the workstation computer 32.

In the further course of the thread running path a thread cleaner 44 is arranged to detect yarn defects.

By means of this thread cleaner 44, the quality of the running thread is constantly monitored, wherein the signals of the thread cleaner 44 are supplied to the workstation computer 32 for evaluation via a signal line 48.

When a yarn defect occurs, a thread cutting device 52 is actuated by the workstation computer 32 via a control line 50 and the thread 22 is separated.

In the thread running direction after the thread cleaner 44, a yarn tension sensor 54 and a paraffining device 46 are still arranged.

The yarn tensile force sensor 54 is also connected via a signal line 56 to the workstation computer 32. During the winding operation, the yarn tension force of the running yarn 22 is constantly monitored by means of the yarn tension sensor 54 and controlled according to the yarn tension force signal supplied by the yarn tension sensor 54 via the workstation computer 32 of the yarn tensioner 36. That is, the brakes 4, 5 of the thread tensioner 36 act on the thread 22 with a contact pressure, which ensures that the current thread 22 sets a substantially constant yarn tension, the one ensures uniform packing density of the supplying cross-wound bobbin 14.

On the waxing device 46 follows in the direction of yarn finally a yarn guide 58, over which the thread 22 runs, for example, on a so-called yarn guide drum 60, which ensures a crosswise laying of the thread 22 according to the winding type "wild winding".

The cross-wound bobbin 14 is rotatably supported by a sleeve, not shown in a pivotally mounted creel 6 and lies with its outer periphery on the motor driven individually driven yarn guide drum 60, which carries the cross-wound bobbin 14 via frictional engagement.

Outside of the regular yarn path, a yarn splicing device 40 is also arranged, which is also connected via a signal line 42 to the workstation computer 32.

The workstation 10 also has a suction nozzle 7 and a gripper tube 8.

The gripper tube 8 serves to grasp the originating from the spinning cop 12 lower thread, which is held in a controlled thread cleaning cut or a thread break above the thread tensioner usually in the thread tensioner 36.

The suction nozzle 7 serves to receive an accumulated on the cheese 14 upper thread.

FIG. 2 schematically shows the workstation computer 32 and its interconnection with the thread tensioner 36, the thread tensile force sensor 54, the thread cutting device 52 and the alarm device 11.

The yarn tensioner 36, which is only shown very schematically in FIG. 2, is known per se and described in detail, for example, in DE 41 30 301 A1. As a yarn tension sensor 54 is preferably a device for use, as is also known for example from DE 41 29 803 Al.

An electrically controllable thread cutting device, as indicated by the reference numeral 52, has also long been the state of the art in textile machinery. Such devices usually have a selectively extendable by an electromagnet cutting edge, which is pressed when energized an electromagnet against a stop and thereby reliably cuts the thread passing in front of the cutting thread.

The workstation computer 32, which in the exemplary embodiment has a yarn tension setpoint generator 13, a yarn tension limit value transmitter 15, a comparator 19, a controller 17, as well as a timer 21, integrated in the comparator 19, for example, is via a signal line 56 connected to the yarn tension force sensor 54, via a control line 38 with the thread tensioner 36, via a control lines 50 with the thread cutting device 52 and a signal line 31 to the alarm device 11.

As further indicated in FIG. 2, the comparator 19 can be supplied by the yarn tension setpoint generator 13 with the yarn tension set point FZK _So ii as well as via the signal line 27 from the limit value transmitter 15 with the corresponding limit values TG via the signal line 24.

About the limit value transmitter 15 is also preferably the time ZS tolerance deviation adjustable, which should pass before the comparator 19 triggered the thread cutting device 52 and the alarm device 11 via the controller 17. Function of the method according to the invention:

During the rewinding process, the yarn 22 unwound from the delivery reel 12 travels, inter alia, between the brake plates 4 and 5 of the thread tensioner 36 on its way to the cross-wound bobbin.

By defined adjustment of the contact pressure of the brake plates

4, 5 is ensured that the thread 22 is wound on the cheese 14 with at least approximately constant yarn tension.

The yarn tension is monitored online by the yarn tension sensor 54 throughout the winding process.

The respectively determined yarn tension actual value FZKi _St is displayed in

Comparator 19 compared with a yarn tension setpoint FZK _So ii, which was specified by the yarn tension setpoint generator 13.

On the output side, the comparator 19 is connected to a regulator 17, which ensures that the thread tensioner 36 always bears the required contact pressure.

The corresponding regulator signal corresponds to a specific one

Contact pressure of the brake plates 4, 5 of the thread tensioner 36.

The determined yarn tension actual value FZK _is also compared in the comparator 19 with limit values TG, which are from the limit value transmitter

15 were specified.

If the comparator 19 determines in its comparison that the yarn tension actual value FZKi _{St has} reached or exceeded the limit values TG for a predetermined time ZS, the thread cutting device 52 is activated via the adjusting line 50 and the running yarn 22 is disconnected.

In addition, the alarm device 11 is actuated via the signal line 31 and the relevant workstation 10 is shut down.

Claims

claims

1. A method for operating a workstation of a cross-wound textile machine, comprising a variable-speed spool drive for adjusting the winding speed of the cheese, a yarn tension sensor connected to a workstation computer for monitoring the thread tension of a thread running from a supply spool and a thread tensioner for regulating the thread tension,

characterized,

in that a value for a desired yarn tension (FZK _So n) and a value (TG) for a permitted percentage deviation from the desired yarn tension (FZK _So ii) can be set at the workstation computer (32) and that the winding operation is performed immediately by the workstation computer (32) is interrupted when it comes to exceeding the allowed percentage deviation of the yarn tension (FZK _So ii). '

2. The method according to claim 1, characterized in that the period of time (ZS), in which it may lead to an unauthorized exceeding of the yarn tension (FZK _So ii) before the winding process is interrupted on the workstation computer (32) is adjustable.

3. The method according to claim 2, characterized in that the predefinable period of time (ZS) between 0.1 sec

5 sec., Preferably about 1 sec.

4. The method according to any one of the preceding claims, characterized in that by the workstation computer (32), when the value of the allowed exceeding of the yarn tension (FZK _So ii) for the predetermined time period (ZS) is reached or exceeded, a controlled thread section is initiated.

5. The method according to any one of the preceding claims, characterized in that by the workstation computer (32), when the value of the permitted exceeding of the yarn tension (FZK _Sol i) for the predetermined period of time (ZS) is reached or exceeded, an alarm is triggered becomes.