WO2005038105A1 - Method and device for the production of a fancy yarn - Google Patents

Abstract

The aim of the invention is to create a method that allows a previously produced fancy yarn to be reproduced. Said aim is achieved by a method in which a model fancy yarn is first guided through a sensor device for measuring purposes, the diameter of the model fancy yarn is continuously measured using the sensor device, the measured diameter values are evaluated, and the formation of the effect of the model fancy yarn is determined therefrom. Spinning settings are generated from the data representing the formation of the effect, and said spinning settings, which are based on the set of data, are used for producing a fancy yarn.

Description

Description:

Method and device for producing fancy yarn

The invention relates to a method for producing a fancy yarn according to the preamble of claim 1 and a device according to claim 14.

A fancy yarn is a yarn in which there are thick spots with predetermined larger diameters and with predetermined lengths, the so-called effects. The intermediate yarn sections with a smaller diameter, that is, the non-effect sections, are referred to as webs. Fancy yarns are becoming increasingly important. Areas of application are, for example, denim fabrics, fabrics for casual wear and home textiles.

Effect yarns can also be produced on rotor spinning machines. For example, the fiber feed to the opening roller of the rotor spinning device is changed by varying the speed of the feed rollers. For this purpose, mechanical gears are driven, which drive machine-long continuous shafts. The feed rollers are set in rotation by means of these shafts. Due to the large mass of the moving parts of such a drive system and the gear play, however, an exact and abrupt change in the yarn thickness at the beginning and end of an effect is difficult or impossible to achieve. The speed when spinning fancy yarn may need to be greatly reduced compared to the speed when spinning fancy yarn. DE 44 04 503 AI describes a rotor spinning machine in which each feed roller is directly connected to an associated stepper motor with its drive shaft. Each stepper motor can be controlled via a control unit. A random generator can be used to generate random changes in the speed of the sliver feed. A fancy yarn with specified effects cannot be produced with this known rotor spinning machine. The disadvantage of yarns produced by means of a random generator lies primarily in the fact that pictures are accidentally created in the textile surface due to chance.

However, programs for controlling ring or rotor spinning machines, in particular their delivery cylinders, have now been developed, with which effects can be set in a targeted manner (see, for example, DE 40 41 301 AI).

It is known to save the effect data of fancy yarns once they have been produced, so that a yarn with the same effects can be produced again at a later point in time. However, if there is an effect yarn that was produced, for example, with a ring spinning machine, but is now to be produced on a rotor spinning machine with a largely similar effect, the existing effect and setting data cannot be transferred directly.

The effect data include in particular the effect lengths, effect diameter, the effect frequency and the respective non-effect thread length or length of the web. It is the object of the invention to propose a method and a device which enable the reproducibility of a fancy yarn once it has been produced.

This object is achieved with a method with the features of claim 1 and a device with the features of claim 15.

Advantageous embodiments of the invention are the subject of the dependent claims.

Through the method according to the invention, all the essential data for the renewed production of a fancy yarn are recorded and brought into a form which makes it possible, for example, on a rotor spinning machine to produce the yarn, regardless of the type of machine on which it was previously manufactured, whereby essentially the characteristic effect structure is recognizable.

In claims 2 to 10 details of the determination of the effect training are claimed, which from the

Cross dimension values delivered by a measuring device result. Above all, it is important to determine the regularity of the repetition of effect lengths and dimensions, including their repeat length, and to eliminate irregularities that are independent of the effect. This is the only way to reproduce the pattern effect.

If the effect achieved is checked in accordance with claim 11, a comparison can be carried out until there is sufficient agreement with the original yarn. That is, it is possible according to the present invention to several cycles to check the result of the respective change of parameters and to initiate a change again. In this way, the yarn can be very close to the original yarn. The compliance check can be carried out either by statistical recording, in particular tabular recording of the effects, that is to say their thickness, length and distribution, or else their visual representation, as is known, for example, using the Oasys® system from Zweigle. In the simplest case, the yarns can be compared visually.

By storing the data according to claim 12 after the adjustment, the reproducibility of this yarn is very good.

When adapting to the original yarn, spinning settings must also be taken into account according to claims 13 and 14, which relate to the basic setting of the machine, which do not fluctuate with the changing cross dimension of the yarn like the directly effect-related data. For example, the thickness of the yarn section can be changed by changing the twist factor. The combing performance of the opening roller influencing the effect is determined both by the type of clothing and by the peripheral speed of the opening roller.

The data then to be fed back to the rotor spinning machine are effective for various control devices. Accordingly, the data contain addresses of control devices for which they are intended. When downloading, this leads to the intended assignment of the data. This also includes data that are only displayed on a display of the central control device. This applies in particular to data that cannot be implemented by the machine itself. The necessary selection of spin materials is mentioned as an example.

A device according to the invention for carrying out the method according to claims 15 to 17 consists of several devices which are alternatively connected to the spinning machine or operated separately from one another. In both cases, these devices are alternatively connected to the control devices of the spinning machine via data lines or are available to the control devices by means of portable data carriers.

The invention is explained using a rotor spinning machine.

Show it:

1 is a schematic diagram of a spinning station,

2 shows the opening device of a spinning station in a simplified schematic representation in partial view,

3 shows a basic illustration of the control, in particular of feed rollers of a rotor spinning machine,

Fig. 4 is a fancy yarn, which is represented by the series of measured values of the yarn diameter and

Fig. 5 shows the schematic representation of a yarn effect. A single spinning station 1 is shown in side view from the large number of spinning stations of a rotor spinning machine. At the spinning station 1, a sliver 3 is drawn from a sliver can 2 through a so-called compressor 4 into the spin box 5 of the rotor spinning device. The device arranged in the spinning box 5 for separating the fibers and feeding them into the spinning rotor 6 are known from the prior art and are therefore not explained in detail. The drive of the spinning rotor 6 is indicated, which consists of a belt 7 running along the machine, with which all the rotors of the spinning stations installed on a long side of the spinning machine are driven. Alternatively, individual drives of the rotors are also possible. The belt 7 rests on the rotor shaft 8 of the spinning rotor 6.

The thread 9 is formed in the spinning rotor 6 and is drawn off through the thread draw-off tube 10 by means of the draw-off rollers 11. The thread 9 then passes a sensor 12, the so-called cleaner, for quality monitoring of the thread. The thread 9 is guided by a thread guide 14 in such a way that it is wound onto a package 15 in crosswise positions. The cheese 15 is carried by a bobbin holder 16 which is pivotally mounted on the machine frame. The cross-wound bobbin 15 lies with its circumference on the winding drum 17 and is driven by it so that the thread 9 is wound up in cross-layers in cooperation with the thread guide 14. The directions of rotation of the cheese 15 and the winding drum 17 are indicated by arrows. The sensor 12 is connected via the line 18 to a local control unit 20 of the spinning station. The control unit 20 is connected via the line 21 to a central computer 22 of the rotor spinning machine. The stepping motor 23 of the feed rollers is connected to the control device 25 via the line 24.

Figure 2 shows details of the dissolution of the sliver 3 in individual fibers. The sliver 3 drawn in by the compressor 4 is clamped between the clamping table 26 and the feed roller 27 and presented to the rapidly rotating opening roller 28. The feed roller 27 is connected to the stepper motor 23 via the drive connection 29. Stepper motor 23 can be controlled via line 24. The direction of rotation of the opening roller 28 is indicated by the arrow 30.

The basic structure of a feed roller control is shown schematically in Figure 3.

The measuring device 31 described in the present example measures the diameter of the yarn presented. Alternatively, the yarn mass could be determined, for example, using a capacitive sensor instead of an optical sensor. When determining the yarn mass, which is usually used as the basis for determining the yarn count, the mass of a yarn section passing through the measuring range is measured, while a mean diameter value within the measuring range is determined in the optical measurement. Both measurements are equally suitable for evaluating the effect formation. In the present example, however, the invention is explained on the basis of the diameter determination.

First, the feed yarn is fed to the schematically illustrated measuring device 31, which detects the measured diameters in relation to the thread length passing through and transmits this data to an evaluation device 32 'of a yarn design unit 32. The transmission is indicated by arrow 33. The effect data are formed from the measured values in the evaluation device 32A. The evaluation device can also be combined with the measuring device 31 or formed by a separate device. The formation of the effect data is explained below in connection with FIGS. 4 and 5.

In the yarn design unit 32, the data required for spinning on a rotor spinning machine is generated using a yarn design software. These data include both the directly effect-related data, which fluctuate with the changing diameter of the yarn, and other data relating to the basic setting of the rotor spinning machine. These include, for example, the rotor, draw-off roller and opening roller speeds, as well as the selection of the spin material. While the latter are preferably called up from a table, the speeds are to be determined by appropriate algorithms. These algorithms are based on known relationships. This involves, for example, determining the warpage from the ratio of the speeds of the take-off rollers to the speed of the feed rollers or the rotations per meter from the rotor speed to the take-off speed and the constriction of the fiber structure associated therewith.

The data generated in the yarn design unit 32 are transmitted via a data bus, here the CAN bus 34, to a central control device 35 of the rotor spinning machine. The transmission can alternatively also with transportable data carriers, such as a compact flash card.

The central control device 35 is connected to the central computer 22 via the data line 36.

A control device 25 includes the control of, for example, 24 stepper motors 23 of the respective feed rollers 27 via lines 24. All 24 spinning stations are constructed in the same way. A control card 40 is connected to the control device 25 by means of a connection device 39.

The data required for the production of fancy yarn for controlling the stepper motors 23 are transmitted from the central control device 35 to the control card 40 via a CAN bus 41. For the production of fancy yarn, the control card 40 converts the data on the thickness and length of the effects and the webs into the control data for the stepping motors 23 to adapt the remaining spinning settings to produce the rotary movement of the feed rollers 27. Via a CAN bus 42 as a continuation of the CAN bus 41, the data required for controlling the stepping motors of the feed rollers are transmitted to further control cards, not shown, which are connected to control devices of further sections of the rotor spinning machine. One of the other control devices is indicated by dashed lines. The other control devices are constructed like the control device 25, have the same connection device and a connected control card. Each additional control device controls in each case the spinning positions of a section of the rotor spinning machine.

If a stepper motor 23 is driven in such a way that it runs faster than the base speed, the feed roller 27 transports more fiber material to the opening roller 28. This has the consequence that more fiber material gets into the rotor 6 per unit of time and the spun thread becomes thicker. The length of the thick spot depends on the length of time for the increased fiber supply. The diameter of the thick point is dependent on the speed of the stepping motor 23 or the feed roller 27.

The central computer 22 also controls the control device 25 via the line 43 when control commands are used to specify whether the control device 25 alternatively controls the production of fancy yarn or the production of fancy yarn.

The freshly spun yarn is measured by one of the sensors 12 or a separate sensor, which is not shown here, and the measured values are sent to the

Yarn design unit 32 is transmitted, which is also provided with a display, not shown, to show the current fancy yarn. If the appearance or the statistical description of the freshly spun yarn does not correspond to the original yarn, further changes must be made. These changes can consist both of the change in the effect parameters that are entered in the yarn design unit and the change of further machine parameters that are generally to be entered on the central computer 22. For this purpose, control connections 44 are available on the central computer can lead, for example, to a control device 45 for the take-off rolls 11 or 46 for the spinning rotors 6, the control devices 45 and 46 being formed, for example, by frequency converters. A display 47 on the central computer also shows the selected spin agents, which have a not inconsiderable influence on the development of the effects.

4 shows the representation of the yarn profile of the fancy yarn as a series of measured values. Effects 48 and webs 49 are recognizable, but the beginning and end of effects 48 as well as the effect thickness or the effect diameter D _E and the web thickness or the web diameter D _{sτ are} not clearly and therefore not sufficiently recognizable.

The measuring device 31 registers the yarn diameter D after each 2 mm yarn length. One cycle step represents a measuring length of 2 mm yarn. 5 shows the yarn diameter D in percent over the yarn length L _G as curve 50. 5, from the left to point 51, represents the web diameter D _S τ. From point 51, curve 50 rises and at point 52 passes the value of the limit diameter D _GR . A point 53 has passed the predetermined yarn length L _v since point 52 was reached. After a diameter increase of 15% is registered at point 52 and the exceeding of the limit diameter D _{GR continues} over the predetermined length L _v, for example six cycles or 12 mm long, point 52 is defined as the beginning of the effect. The curve 50 falls below the limit diameter D _GR at point 54. The drop below continues until point 55 and thus over the predetermined yarn length L _v . This will end point 54 of the effect defined. The effect length L _{E is} determined from the beginning and end of the effect between point 52 and point 54. An arithmetic mean is formed from the four largest diameters 56 within the effect. As a result, the specification of the effect diameter is largely independent of natural diameter fluctuations in the effect area. This arithmetic mean is defined as the effect diameter D _E.

The areas between the effects defined in this way are the webs with the basic diameter of the yarn. To determine the repeat, a number of successive effects and bars are first compared with the same number of subsequent effects and bars. This number should advantageously be below the expected repeat length. The measure of agreement contains a statement as to whether the sequence of effects and bars on which the comparison is based corresponds to the repeat length. To do this, the number of effects / bars to be included in the comparison must be gradually increased. If there is a maximum when a certain number of effects / bars is reached, which differs significantly from the neighboring values, this value corresponds to the repeat length.

This is the last prerequisite for a reproduction of the sample yarn.

Claims

claims: 1. Process for the production of a fancy yarn which corresponds to an existing pattern fancy yarn, characterized, that first the pattern effect yarn for measuring by a Measuring device is guided that at least one of the The diameter and mass of the pattern effect yarn are continuously measured so that the measured values are evaluated and from this the Effect formation of the pattern effect yarn from effect areas and intermediate webs is determined from the data representing the effect formation Data set is formed that spinning settings are generated, which are based on the previously formed data set, and that a fancy yarn is produced with these spinning settings. 2. The method according to claim 1, characterized in that the effect area is determined by the fact that the beginning of the effect is defined by fulfilling a first criterion and that the end of the effect is defined by fulfilling a second criterion, that a definable between the beginning and end of the effect Number of largest measured values is determined that an average value is formed from the determined measured values, which is the transverse dimension of the effect represents, and that the effect length is determined from the beginning and end of the effect. 3. The method according to claim 2, characterized in that the transverse dimension of the web D _S τ is determined outside the effect area in order to determine the relative transverse dimension of the effects. 4. The method according to claim 2 or 3, characterized in that to determine the transverse dimension of the web D _sτ an arithmetic mean of the transverse dimension of the yarn is first formed from a predetermined length of yarn as a reference, that the reference value is subtracted from the individual values of the transverse dimension of the yarn and that the transverse dimension of the web D _{sτ is then formed} as an arithmetic mean value from all negative values that were measured adjacent to other negative values. 5. The method according to any one of claims 2, 3 or 4, characterized in that the transverse dimension of the D _{E of} the effect is formed as an average of the four largest transverse dimensions between the beginning and end of the effect. 6. The method according to any one of claims 2 to 5, characterized in that as the first criterion Exceeding a limit value of the transverse dimension D _GR is greater than the transverse dimension of the web D _sτ by a defined amount and that the exceeding continues over a predetermined yarn length L _v and that the second criterion is that the limit value D _{GR is} undershot applies and the falling below a predetermined yarn length L _G lasts. 7. The method according to claim 6, characterized in that the limit value D _{GR is} 15% greater than the transverse dimension of the web D _S τ- 8. The method according to claim 6 or 7, characterized in that the predetermined yarn length is assumed to be reached when the criterion is met over 6 consecutive measured values. 9. The method according to any one of claims 6 to 13, characterized in that a measurement value is recorded every two millimeters when measuring the yarn diameter. 10. The method according to any one of claims 1 to 9, characterized in that the repeat length of the effect training is determined in that - starting at a selected point in time, a number of the most recently measured effects and bars are compared with the same number of subsequent effects and bars, - that the degree of agreement of the effect sequences consisting of the effects and bars is determined, - that the number of effects and webs on which the comparison is based is gradually increased and - That the repeat length is defined by the number of effect sequences at which the degree of agreement reaches a maximum. 11. The method according to claim 1, characterized in that the yarn produced is also measured that the The effect formation of the yarn produced is determined and compared with the effect formation of the pattern effect yarn, that the spinning settings are changed until there is sufficient agreement between the effect formation of the manufactured yarn and the effect formation of the pattern effect yarn. 12. The method according to claim 11, characterized in that the data set of the spinning settings for the production of fancy yarn after the adjustment is stored under a label that ensures retrieval. 13. The method according to claim 12, characterized in that the spinning settings, which in addition to the directly effect-related data which fluctuate with the changing transverse dimension of the yarn, also contain further data relating to the basic setting of the spinning machine, such as rotor speed, opening roller speed and selection of the spinning means a storage medium for the new production of fancy yarn. 14. The method according to claim 12 or 13, characterized in that the data are provided with addresses and are addressed to the control units (22, 25, 35, 45, 46) provided for the corresponding control operations. 15. The apparatus for performing the method according to claim 1, characterized by a measuring device (31) for determining at least one parameter diameter and mass of a pattern effect yarn, an evaluation device (32A) which determines the effect data of the pattern effect yarn from the measured values, - A yarn design unit (32) which generates the data required for spinning on a spinning machine, in particular a rotor spinning machine, from the effect data using a yarn design software - Control devices (22, 25, 35, 40) for controlling the drives (6, 11, 23) of the spinning machine on the basis of the data transmitted by the yarn design unit (32). 16. The apparatus according to claim 15, characterized in that the devices (31, 32A, 32) upstream of the control devices (22, 25, 35, 40), but at least the measuring device (31), are designed as separate devices. 17. The apparatus according to claim 16, characterized in that the separate devices (31, 32A, 32) via data connections (33, 34) are coupled to the control devices (22, 25, 35, 40).