EP1868933A1

EP1868933A1 - Yarn rewinding method and device

Info

Publication number: EP1868933A1
Application number: EP06723499A
Authority: EP
Inventors: Joe Reichmuth
Original assignee: SSM Schaerer Schweiter Mettler AG
Current assignee: SSM Schaerer Schweiter Mettler AG
Priority date: 2005-03-31
Filing date: 2006-03-17
Publication date: 2007-12-26
Also published as: WO2006103001A1; EP1707523A1

Abstract

The invention concerns a method and a device for rewinding yarns at a certain reeling speed. The inventive method consists in reeling a yarn from a feeding spool (3) and winding said yarn onto a yarn support (7) rotating at a certain winding speed, the yarn being guided on a trajectory (10) from the feeding spool (3) to the yarn support (7). A variable control of the yarn reeling speed is determined by the feeding spool (3), preferably in the trajectory (10) upstream of a feeding reeling mechanism (17) establishing a reeling speed. Said reeling speed is then adjusted by an adjusting module (19) based on the determined variable control.

Description

Method and device for rewinding yarns

The invention relates to a method for rewinding yarns at a take-off speed, comprising the steps of stripping a yarn from a supply spool, and winding the yarn on a yarn carrier rotating at a take-up speed, the yarn passing over one

Yarn run from the feed bobbin to the yarn carrier and a device for carrying out the method (rewinding device).

Such rewinding devices are used in particular for producing reels with yarn windings adapted to a subsequent process.

Rewinding of yarns is often done in yarn making. The yarns are to be wound on spools in such a way that the spools in subsequent processes can be used optimally as feed bobbins. In particular, the type of winding and its density should be optimized. Thus, in some yarn processing processes, it is not tolerable if the yarn is unrolled randomly on the supply spool, that is to say has a so-called "wild winding." Further, during processing of yarns, eg during dyeing, the yarn to be dyed is rewound or it is a coil is wound with a yarn having a predetermined yarn length, ie a predetermined length of run.

The rewinding should be carried out with the highest possible winding speed (rewinding speed). However, as the winding speed increases, so does the yarn tension of the yarn to be rewound during the rewinding process, and yarn tension variations are more pronounced. The latter leads to a deterioration in the quality of the winding on the coil created, since thread tension fluctuations during winding lead to Garndichteschwankungen of the windings. The latter can in turn worsen the unwinding of these coils in subsequent processes. Further, the thread tension variations can easily lead to thread breaks during rewinding. The latter occurs especially in areas of integer Windungsverhältnis, ie the ratio of coil rotation to Doppelhubzahl, so-called mirror zones, the supply coils heaped up. In these areas, the thread layers are close to each other without being fixed by crossing points, which can lead to entrainment of adjacent threads and thus thread tension peaks or thread breaks in the overhead deduction. These thread tension peaks severely limit the rewinding speed.

It is known from EP 0 875 479 A1 that the yarn tension of yarns in yarn conditioning processes associated with rewinding processes, e.g. Oiling, dyeing or stretching yarns, to measure and regulate. The yarn tension of a yarn is measured in the yarn path after a conditioning shortly before its winding. It is attempted to keep the yarn tension in a predetermined yarn tension range constant by means of a yarn tension control module according to a control variable derived from the measured yarn tension. The yarn tension control module in this case comprises a yarn brake and / or a controllable delivery mechanism, by means of which the yarn tension is regulated by braking and / or accelerating the yarn speed of the yarn.

Usually, the yarn is withdrawn from the supply spool by the rotating movement of a take-off roll (deduction feed). The take-off roll typically includes a main engine-driven roller and a passive separation roller that controls the geometry of wraps of yarn around the main roller sets. In order to avoid yarn tension variations in the unwinding region, it is known to exert a pressing force on the main roll by means of a "nip-roller", that is to say a further roller. This traps the yarn between the main roll and the other roll, causing the yarn to be pulled off at the tangential speed of the main roll. Further, various biasing systems disposed between the platen and a delivery mechanism are known to increase and stabilize the yarn tension of the supply spool as it is withdrawn from the supply spool. The yarn is often pulled off during rewinding overhead. When pulling off overhead, the feed bobbin does not rotate itself, so working with an immediately usable spare bobbin is possible when pulling off overhead.

In addition to the yarn tension peaks mentioned due to mirrors of the supply bobbin, the yarn tension of the yarn in the yarn path during rewinding varies for various other reasons:

By reducing the diameter of the supply spool with time by unwinding the yarn, the geometry of the "balloon" formed by the yarn movements along the spool axis changes accordingly, which influences the yarn tension. - By increasing the speed of the balloon with decreasing diameter of the withdrawn coil, the centrifugal forces acting on the yarn in the "balloon" increase, which leads to a thread tension increase.

It has been found that the thread tension fluctuations in known rewinding can be reduced only insufficiently while maintaining a high rewinding speed, in particular stress peaks occur in mirror zones. To avoid thread breakage, the max. Withdrawal speed of the yarn from the supply spool tuned to the worst areas of the supply spool, and thus is used in the areas of lower yarn tension when pulling the yarn at a take-off speed, which is far below the allowable take-off speed.

The invention has for its object to provide a method and apparatus for rewinding yarns are detected in the yarn tension peaks and areas of high yarn tension on a supply spool to lower the unwinding speed in these areas so far that a yarn breakage is avoided.

This object is achieved by the method and apparatus of the independent claims. The dependent claims represent preferred embodiments of the invention.

In the method according to the invention for rewinding yarns, a take-off speed control variable of the yarn from the supply bobbin, in the region of a take-off zone upstream of a take-off delivery unit defining a take-off speed, is defined for a defined quality of the windings and / or one

Brake determined and the withdrawal speed is controlled by a control module depending on the Abzugsgeschwindigkeitskontrolle size. The inventive method is based on the finding that the causes of most thread tension fluctuations of parameters of the supply spool, or parameters with which the yarn is unwound from the supply spool depend. The take-off speed control quantity is thus determined by the feed bobbin during the winding operation in a case of several possibilities. If an increase in the thread tension of the yarn is detected or expected via the take-off speed control variable, the Withdrawal speed, eg by controlling the Aufwickeigeschwindigkeit, temporarily lowered. Alternatively, the withdrawal speed can be controlled by controlling the take-up speed.

With the method according to the invention, the thread tension in the peel-off region is stabilized, so that a regular profile of the thread tension over time, independent of e.g. the diameter of the feed bobbin, is complied with. Furthermore, it is possible to significantly increase the average take-off speed over the entire bobbin travel. It is an increase in the production rate of the manufacturing process, while maintaining quality, possible because thread tension peaks and thereby caused yarn breaks are avoided.

The stabilization of the withdrawal thread tension depends on the withdrawal speed. The withdrawal speed is the manipulated variable for the withdrawal thread tension. The objective is to maximize the

Withdrawal speed on the basis of the withdrawal tension as controlled variable. Increasing production speed is the primary goal here. An equalization of the winding tension is a positive side effect. The thread tension can be kept constant regardless of the quality of the yarn, the diameter of the supply spool and the selected withdrawal speed. In addition to being able to controllably increase or decrease the yarn tension when unwinding from the supply spool, if necessary, the yarn tension can be permanently reduced, thereby enabling higher production speed and efficiency.

A withdrawal thread tension, preferably by measurement by a thread tension sensor, is preferably determined as the take-off speed control variable. This provides a simple and inexpensive way to determine the take-off speed control size. Determining the take-off speed control variable may advantageously be above target winding speed values as a function of a current diameter of the supply bobbin and / or the current weight of the supply bobbin and / or the length of the yarn still on the supply bobbin and / or of optical monitoring data of a withdrawal balloon of the supply bobbin and / or of optical monitoring data of mirror zones on the supply spool done. The remaining length of the yarn still present on the supply bobbin can be determined from the already rewound length (running length) of the yarn with known total length. As a result, a thread tension fluctuation can be counteracted even before it occurs by reducing the take-up speed. By means of diameter detection, length measurement or weight detection can be concluded directly on an increase in the withdrawal thread tension, since this increases with decreasing radius of the supply spool at a constant take-off speed. The diameter of the feed bobbin can also be converted into weight ranges or run lengths. In the optical detection of mirror zones existing cross angle are evaluated in the winding of the supply spool. Mirror zones only occur in the case of wild winding, in which the traversing speed is in a constant relation to the winding speed. With this winding principle, the supply bobbins pass through integer winding ratios for certain diameters, in particular as a function of the crossing angle. One can therefore already calculate the problem zones or critical diameters on the basis of the crossing angle,

In addition, it is particularly advantageous to measure a take-up yarn tension, by means of a yarn tension sensor, and to control the take-off speed of the take-off supply as a function of the take-up yarn tension and / or the take-up yarn tension is arranged in the yarn path Thread brake module regulated. The winding tension is thereby separated from the take-off speed, which is advantageous for the uniformity of the coil structure.

A rewinding device according to the invention for rewinding yarns comprises:

- A supply spool recording, set up for Aufnage a supply bobbin with a yarn to be deducted, and

- A rotatable with a take-up Garnträgeraufnahme, adapted for receiving a yarn carrier to which the yarn is wound up, wherein the yarn can be guided over a yarn path from the supply spool to the yarn carrier.

According to the invention, control quantity receiving means are provided, configured to determine a take-off speed control variable of the yarn from the supply reel, wherein a control module is provided, configured to control the rewinding device for regulating a take-off speed as a function of the take-off speed control variable. The rewinding device is preferably configured to rotate the yarn carrier receptacle with the winding speed, it is then designed as a winding unit for driving the Garnträgeraufnahme. The control module is then set to control the take-off speed by controlling the take-up speed.

The rewinding device according to the invention is set up to carry out the method according to the invention and thus provides the advantages of the method according to the invention.

Advantageously, a take-off delivery unit is provided in the yarn path, set up to set a take-off speed of the yarn, wherein the control-size receiving means are set up Determine the deduction speed control size on the thread or on the feed bobbin before the deduction delivery unit. This embodiment is particularly suitable for overhead removal of the supply spool. The rewinding device can be set up to drive the deduction delivery mechanism, wherein the control module is then set up to regulate the rewinding by controlling the withdrawal speed.

Particularly robust and easy to manufacture, the rewinding device according to the invention, when the control size receiving means have a yarn tension sensor, set up as

Abzugsgeschwindigkeitskontrollegröße a Abzugsfadenspannung by measurement to determine.

The rewinding device according to the invention can have as a control size receiving means means for determining the

Abzugsgeschwindigkeitskontrollegröße About Sollumspulgeschwindigkeitswerte depending on a current diameter of the supply spool and / or the current weight of the supply spool and / or still on the feed bobbin length of the yarn and / or optical monitoring data of a withdrawal balloon of the supply spool and / or optical monitoring data of mirror zones the supply spool are provided. As a result, the thread tension is measured and controlled both in the area of the supply spool and in the area of the yarn carrier, which is advantageous in the case of an interleaving yarn processing process.

A yarn processing machine according to the invention has at least one rewinding device according to the invention. The invention will be explained in more detail by means of embodiments with reference to the drawings.

FIG. 1 shows a rewinding device according to the invention. FIG. 2 shows the thread tension as a function of the spool travel in front of the take-off delivery unit of a rewinding device according to the prior art.

The figures of the drawings show the subject matter of the invention in a highly schematic manner and are not to scale. The individual components of the article according to the invention are shown so that their structure can be well shown.

FIG. 1 shows a rewinding device 1 according to the invention for rewinding yarns. The yarn is unwound from a supply spool 3, which is arranged in a feed bobbin receptacle 4 for overhead removal. A yarn carrier 7, on which the yarn is wound, is arranged in a yarn carrier receptacle 8. A not shown Umspulaggregat that is designed as a winding unit for driving the Garnträgeraufnahme 8, drives the Garnträgeraufnahme 8 such that it rotates at a take-up speed. In general, the rewinding unit is an electric motor which engages the yarn in such a way that it can at least influence the rewinding speed. The yarn is guided during rewinding in a yarn path 10 of the supply spool 3 to the yarn carrier 7. In the area of the supply bobbin 3, the yarn path 10 forms a discharge balloon 11. By a thread guide, not shown, which allows an orderly yarn winding on the yarn carrier 7, the yarn path 10 is widened in a funnel shape in front of the yarn carrier 7. In order to enable a regulation of the take-off speed, as a function of parameters of the supply bobbin 3, a take-off speed control variable is detected and measured in a take-off zone 12a. It is in the Embodiment of Figure 1 as a control size receiving means a yarn tension sensor 15 in the yarn path 10 in front of a deduction delivery 17, which determines the withdrawal speed of the yarn by its rotational speed provided. The yarn tension sensor 15 measures withdrawal tension values of the yarn take-up yarn tension from the supply bobbin 3 in the yarn path 10 before the take-off supply unit 17 continuously. These take-off tension values are used as a take-off speed control quantity of the yarn from a control module 19 in order to control the take-up speed of the yarn carrier receptacle 8 and thus of the yarn on the yarn carrier 7 as a function of the take-off speed control variable.

The rewinding device 1 further comprises a threadline tension control module 20. This yarn thread tension control module 20 is set up to measure a yarn thread tension in the yarn path 10 shortly before the yarn carrier 7, that is to say a take-up yarn tension, by means of a further yarn tension sensor 22. The take-off speed of the take-off delivery mechanism 17 is regulated by the thread-yarn tension control module 20 as a function of the threadline tension. Furthermore, the yarn speed in the yarn path 10 can be regulated as a function of the yarn thread tension by means of a yarn braking module 25 arranged in the yarn path 10.

FIG. 2 shows the thread tension S in centinewtons [cN] as a function of the spool travel t in front of the take-off delivery unit of a rewinding device according to the prior art. Spool travel t is understood to mean the time course of the entire unwinding process. The thread tension S increases with increasing unwinding of the supply spool, with their fluctuations increasing sharply. The increase in the yarn tension S has its main cause in the decreasing supply spool radius, which leads to higher speeds of the yarn at the same take-off speed. The transition between different mirror zones of the supply bobbin results in a strong short-term increase in the thread tension (Thread tension tips 33). By controlling the withdrawal speed, the method according to the invention makes it possible to avoid yarn tension fluctuations as far as possible, in particular also in mirror zones during the entire package travel t. The thread tension peaks 33 occurring in the prior art are dispensed with when using the method according to the invention.

Proposed is a method and apparatus for rewinding yarns at a take-off speed. The method comprises the following method steps: unwinding or withdrawing a yarn from a supply spool 3, and winding up the yarn on a yarn carrier 7 rotating with a take-up speed, the yarn being guided over a yarn path 10 from the supply spool 3 to the yarn carrier 7. A take-off speed control quantity of the yarn is determined by the supply reel 3, preferably in the yarn path 10 before a take-off delivery 17 defining a take-off speed, and the take-off speed is controlled by a control module 19 as a function of the take-off speed control variable.

The invention is not limited to the above

Embodiments. Rather, a number of variants are conceivable, which make use of the features of the invention even with fundamentally different type of execution.

Claims

claims

1. A method of rewinding yarns at a take-off speed, with the method steps

- Taking a yarn from a supply spool (3), and

Winding the yarn onto a yarn carrier (7) rotating with a take - up speed, the yarn being fed through a yarn path (10) of the yarn carrier (7)

Supply reel (3) to the yarn carrier (7) is guided, characterized in that a withdrawal speed control size of the yarn from the supply spool

(3), to a beginning of the yarn path (10), before a deduction delivery (17) and / or a brake is determined and the withdrawal speed of a control module (19) in dependence on the

Trigger speed control variable is regulated.

2. A method for rewinding yarns according to claim 1, characterized in that the take-off speed is controlled by controlling the take-up speed.

3. A method for rewinding yarns according to claim 1 or 2, characterized in that As Abzugsgeschwindigkeitskontrollegröße a withdrawal thread tension, preferably by means of measurement by a yarn tension sensor (15) is determined.

4. A method of rewinding yarns according to at least one of the claims

1 to 2, characterized in that the determination of the take-off speed control variable above the reference winding speed values as a function of a current diameter of the supply spool (3) and / or the current weight of the

Supply spool (3) and / or still on the supply spool (3) located length of the yarn and / or optical monitoring data of a withdrawal balloon of the supply spool (3) and / or optical monitoring data of mirror zones on the supply spool (3).

5. A method for rewinding yarns according to at least one of claims 1 to 4, characterized in that a take-up yarn tension, by means of a yarn tension sensor (22) is measured and the take-off speed of a deduction delivery (17) is regulated in dependence on the winding tension and / or the Winding tension by means of a thread in the run (10) arranged yarn brake module (25) is controlled.

6. rewinding device (1) for rewinding yarns with a

Withdrawal speed, with

- A supply spool receptacle (4), adapted for receiving a supply spool (3) with a yarn to be deducted, and a yarn carrier receptacle (8) rotatable with a take-up speed and adapted to receive a yarn carrier (7) on which the yarn can be wound, wherein the yarn can be guided via a yarn path (10) from the feed bobbin (3) to the yarn carrier (7), characterized in that

Control size receiving means are provided, arranged to determine a deduction speed control size of the yarn from the Vorlagespuie (3), wherein a control module (19) is provided, arranged to control rewinding device (1) for regulating a take-off speed in dependence on the Abzugsgeschwindigkeitskontrollegröße.

7. rewinding device for rewinding yarns according to claim 6, characterized in that a deduction delivery unit (17) in the yarn path (10) is provided, set to set a take-off speed of the yarn, wherein the

Control size receiving means are arranged to determine the Abzugsgeschwindigkeitskontrollegröße in a fume hood (12a) before the deduction delivery (17).

8. rewinding device for rewinding yarns according to claim 6 or 7, characterized in that the rewinding device (1) is arranged to rotate the Garnträgeraufnahme (8) with the winding speed, wherein the control module (19) is set the take-off speed by controlling the take-up speed regulate.

9. rewinding device for rewinding yarns according to at least one of claims 6 to 8, characterized in that the control size receiving means comprise a yarn tension sensor (15), set up to determine a take-off yarn tension by means of measurement as the take-off speed control variable.

10. rewinding device for rewinding yarns according to at least one of claims 6 to 8, characterized in that the control size receiving means are means for determining the Abzugsgeschwindigkeitskontrollegröße about Sollumspulgeschwindigkeitswerte depending on a current diameter of the supply spool (3) and / or the current weight of Supply spool (3) and / or the still on the supply spool (3) located length of the yarn and / or optical monitoring data of a withdrawal balloon of the supply spool (3) and / or optical monitoring data of mirror zones on the supply spool (3) are provided.

11. Yarn processing machine with at least one rewinding device according to at least one of claims 6 to 10.