EP1000186A1

EP1000186A1 - Method for producing compacted yarn and device therefor

Info

Publication number: EP1000186A1
Application number: EP99936352A
Authority: EP
Inventors: Andreas Olbrich
Original assignee: Zinser Textilmaschinen GmbH
Current assignee: Oerlikon Textile GmbH and Co KG
Priority date: 1998-05-29
Filing date: 1999-05-31
Publication date: 2000-05-17
Anticipated expiration: 2019-05-31
Also published as: JP4484187B2; EP1000186B1; JP2002517617A; DE59903309D1; DE19824078C2; DE19824078A1; WO1999063139A1

Abstract

In order to recognize, indicate and, optionally, to automatically prevent malfunctions from occurring in compacting devices (14) used in the production of compacted yarns on spinning machines, the hairiness of the yarn thus produced is monitored by means of sensors (17) and when a predefined limiting value of the control device (4) is exceeded with respect to said hairiness, a shutdown signal and/or a warning signal is given. Since the number of especially long protruding fibres varies significantly between compacted and non-compacted yarns, the number of protruding fibres belonging to a higher class of length is chosen as a criterium for a malfunction of the compacting device.

Description

Process for the production of compacted yarn and device therefor

The invention relates to a method in the production of compacted yarn, in particular for monitoring the function of compacting, and to devices which can be used in such a method.

A compressed yarn is understood to mean a yarn in which, prior to the twisting of the fiber sliver, from which the finished yarn is formed by turning, usually in particular projecting edge fibers are applied to the fiber sliver by means of an air stream directed against the center of the fiber sliver, but also the Packing density of the fibers in the fiber sliver itself is increased. This in particular reduces the hairiness of the yarn produced, but also improves other quality parameters of the yarn, such as the increased use of substances by better incorporation of the fibers and thus the strength of the yarn.

Hairiness of a yarn is understood here to mean both the number of fibers protruding from the yarn produced and their protruding length. Hairiness is both inevitable with staple fiber yarns and indispensable for the textile character of the yarns. However, excessive hairiness is undesirable. It reduces the tensile strength of the yarn because the protruding fibers do not contribute to this; it causes breakage of the protruding fibers during the processing of the yarn and thereby weight loss of the yarn and annoying fiber fly; it affects a smooth product appearance of a fabric made from the yarn (woven, knitted), etc. Sometimes yarns or Flat structures are even freed of protruding fibers by singeing.

In general, undesirable fibers are particularly undesirable. The following are used to describe hairiness

Fibers are usually divided into length classes of their protruding lengths of, for example, two to two millimeters. The length classes up to 4 mm m are as a rule both for the textile character of the

Yarns are desirable and cannot be avoided by compression spinning. In the length classes from 6 mm to 8 mm, for example

Number of protruding fibers between normally spun yarns and densified spun yarns [but so significant that this

Difference can serve to distinguish densely spun yarn from spun yarn that is normally or incorrectly not compacted.

Densified yarn can be produced, for example, by exposing the fiber sliver emerging from the pair of exit rollers of a drafting system, for example a ring spinning machine of a certain width, to an air flow which is directed transversely to the yarn and which forces the fibers, particularly in the edge region of the fiber sliver, towards their center.

A large number of devices have become known for compressing yarns or fiber slivers to be processed into yarn. Hollow suction rolls with circumferential perforations in the shape of a line of small suction openings have been proposed. Flexible, revolving, standing under suction Rie chen with the perforation are known. The method according to the invention and the device according to the invention are independent of the type of compression device, i.e. they can be implemented with different compression devices.

Such compression devices sometimes fail. In particular, it can happen that the induced draft does not apply because For example, the pipeline transmitting the suction to the compression device is blocked or the suction openings of the perforation are blocked. Compression slips can break. The fiber sliver can run out of the effective area of the suction traction, etc. Such errors are inconspicuous and are therefore often not discovered for a very long time, so that yarn that is not compressed and thus defective is produced for a long time.

The object of the invention was accordingly to detect and report a failure of the compression effect. It solves this task procedurally by the features mentioned in the characterizing part of claim 1. Because the achievement of the intended effect, namely the reduced hairiness of the yarn produced, is checked and monitored, the monitoring of this single parameter not only covers all possible causes which can cause the compacting to fail, but also already Slacken and not notice a complete failure of the compaction.

The invention has recognized that the effect of the compression of a yarn or a fiber sliver preferably has an effect on protruding fibers with a greater protruding length, and a detection of the number of such fibers accordingly represents a particularly clear indication of the lack of a compression effect. It is therefore preferably provided to check and monitor the compaction effect on the basis of the hairiness caused by long protruding fibers. In this case, it is preferable to proceed in such a way that a tolerable number of protruding fibers of, for example, 6 to 8 mm protruding length is specified on a specific yarn length, the number of such fibers occurring is detected and an error signal is emitted when the predetermined limit value is exceeded.

Devices for detecting the hairiness of yarns are known and are therefore not described and illustrated in more detail. The hairiness can be checked and monitored on the yarn itself or on the bobbin to which the yarn is wound, because hairy yarn also leads to a hairy bobbin. It has been shown that the hairiness of a yarn on the cop is expressed even more clearly because apparently fibers that are not embedded in the yarn are erected when the yarn passes through the runner and protruding fibers follow through the centrifugal force of the cop rotating at high speed are thrown outside and preferably stick out. Spooling the yarn later can further increase hairiness due to the reversal of its direction.

Checking and monitoring hairiness can also be done at various points in the treatment of the yarn. In this way, the yarn can be checked directly at the spinning point at the exit from the drafting system, after winding on the bobbin or at a downstream point, for example when rewinding. Detecting the hairiness at the spinning position has the advantage that, in the absence of the compaction effect, it is possible to intervene immediately at the work location in question and the production of faulty yarn is immediately prevented. Be. a check of the yarn at the spinning station also eliminates the need for precautions by means of which a yarn can be assigned to a spinning station from which it has meanwhile been removed. It can be provided that each work station is equipped with a sensor.

On the other hand, since the hairiness of the yarn increases in the course of its processing, e.g. when passing through the belt runner, due to centrifugal forces or thermal forces on the rotating bobbin, by reversing its direction of rotation when rewinding, etc., checking the following treatment steps leads to a clearer result.

Detecting the hairiness at a subsequent processing stage of the yarn also has the advantage that the throughput speed of the yarn there is generally significantly higher than at a spinning position and the utilization of the device accordingly is higher or a smaller number of such devices is required. As such a subordinate processing point ospw. the winding of the yarn from the spinning bobbins to packages.

The checking and monitoring of the hairiness on the cop is advantageously carried out on a device handling the cops, on which the cops are required and can be guided past a hairiness sensor.

Another advantageous possibility of checking and monitoring the hairiness consists in moving a hairiness checker along the row of the spinning or rewinding points of the yarn or the cops on the spindles of the ring spinning machine. A large number of yarns or cops can be checked and monitored with just one hairiness sensor.

If it is determined that the compaction effect does not occur or does not occur to the desired extent, a signal is emitted, by means of which an intervention in the manufacturing process is made possible. The signal can give a warning that allows manual intervention by an operator. However, the signal can also intervene directly, for example by stopping the incorrectly operating spinning station and thus preventing the production of further defective material.

A device by means of which the method according to the invention can be carried out has the components listed in the characterizing part of claim 10. The hairiness sensor can be designed so that it detects the length and number of protruding fibers or only the number of protruding fibers of a minimum length and passes them on to the control device as a signal. In the former case, the control device is designed in such a way that it sorts the incoming signals according to length classes and determines these frequencies. The control device is also provided with a device for recognizing the exceeding a limit of the detected protruding fibers in a length class.

If the checking and monitoring of the hairiness on the yarn or on the bobbin is detected by hairiness sensors arranged at each spinning station or guided past each spinning station, the assignment of an error signal to a spinning station is readily given.

If, on the other hand, the checking and monitoring of the hairiness is carried out on a downstream device that processes the yarns, for example a winder or on a cop removed from the spinning station, by arranging hairiness sensors there or by guiding them there, or when cops are passed by a hairiness sensor Precautions are taken that make it possible to assign an error signal that has occurred to the spinning station from which this yarn or cop comes. This can be done by providing yarn carriers, for example copellers carrying yarn cores or spinning heads, with a spinning station-related coding, by means of which the spinning station from which a yarn originates can be identified. A device that can be used for this is known, for example, from DE 36 03 002 AI.

Further advantageous embodiments of the invention are described in the subclaims.

In the figures of the drawing, embodiments of the invention are shown purely schematically. 1 shows the cross section through one side of a ring spinning machine; Figure 2 shows the floor plan of a spinning system with ring spinning machine and winding machine. Fig. 3 shows the view of a cop on a copeller. The invention is described below in application to a ring spinning machine and to a winding machine. However, their use is not restricted to these machines, but rather can be implemented in conjunction with any other devices and machines which manufacture or process compacted yarns.

1 shows only the essential components of a common ring spinning machine 1: roving bobbins 2, from which roving 3 runs, drafting system 4 with three pairs of rollers 5, 6 and 7, and ring spinning device 8 with thread guide 9, ring bench 10 with ring and rotor, and spindle 11 with the attached cop 12.

The ring spinning machine 1 according to the invention has a sliver stop device 13, which can be of any type. It is assumed that the known sliver stop device 13, which is therefore not shown in detail, is designed as a half-shell which partially encompasses the lower roller of the input roller pair 5 of the drafting device 4 and which is pivoted about this lower roller to interrupt the feed of roving, thereby lifting the upper roller of the roller pair thus interrupting the further supply of roving to the drafting system.

Furthermore, the ring spinning machine 1 according to the invention has a compacting device 14 in the form of a suction lower roller 15 at the outlet of the drafting device 4, to which an upper roller 16 is assigned. As already mentioned, other compression devices are also known - the present invention is not tied to a compression device of a specific embodiment.

Between the compression device 14 and the thread guide 9 of the ring spinning device 8, a hairiness sensor 17 is arranged, through which the yarn 18 passes and in which the hairiness of the yarn produced is detected. Such hairiness sensors are known and are therefore not described in detail here. The measurement signal of the hairiness sensor 17 corresponding to the determined hairiness is fed to a control device 20 via a measurement value line 19. In this control device 20, the incoming signal is compared with a permissible limit value for hairiness that is predefined for the control device. This comparison is based on the number of protruding fibers m of a certain length class of, for example, 6 mm to 8 mm. This differentiation can take place in the hairiness sensor 17, in that it is designed to be sensitive only to protruding fiber lengths of this length class. However, it is also possible to arrange protruding fiber lengths m length classes m of the control device 20.

If the limit value is exceeded, the control device 20 can emit an actuating signal to the match stop device 13 via the control line 21, which triggers it. This initially prevents further production of defective yarn. The control device 20 can, however, also emit an alarm signal to a warning device such as a warning lamp 23 instead of the control signal or in addition to this via a signal line 22, by the lighting of which the operator is made aware that defective yarn with excessive hairiness at a work site is delivered. This warning signal offers the operator the opportunity to check the function of the compression device 14 and, if necessary, to restore it.

In the embodiment of FIG. 2, each work station 24 of a winding machine 25, in which the yarn 18 m is wound into cross-wound bobbins 18 m in a more common and therefore not shown and described manner here, with a hairiness sensor 17 for detecting the hairiness of each in a work station rewound yarn 18 equipped. The measured values of these hairiness sensors 17 are supplied to the control device 20, for example, in the bus system via a collecting line 26. There they will be compared with the limit value specified for the control device 20. If this is exceeded, a warning signal can be issued by which the operator is made aware that faulty yarn is running at the relevant work station 24 of the winding machine 25 and so that it can intervene.

If the ring spinning machine 1 according to FIG. 2 is equipped with a transport device 27, the scanning of the heads 12 for hairiness can advantageously be carried out on this transport device. Common and therefore not shown and described here transport devices have an endless traction member 29, which is guided around deflecting rollers 28 and has carriers, by means of which copellers 30 shown in FIG. 3 can be conveyed around the ring spinning machine 1, to which a common cop changing device of any embodiment can be used the spin-dein 11 stripped heads 12 are attached.

To scan the heads 12 for hairiness, a hairiness sensor 17 ', which is connected to the control device 20, can be arranged on the transport device 27 rotating in the direction of the arrow P at a point where all the heads 12 pass, which is connected to the control device 20. In this embodiment, the operation of all spinning positions associated with the transport device 27 can be monitored with only one hairiness sensor 17 '.

In the cases in which the determination of a faulty spinning station is not carried out directly at the spinning station and the assignment of an error signal to the fault location is not readily provided, precautions must be taken to enable this assignment.

In the embodiment in which the cops 12 conveyed by means of the transport device 27 are checked for hairiness by means of a hardness sensor 17 'arranged on the path of the transport device, this assignment can be carried out by automatically counting the number of hairiness sensors posed cops. The control device 20 can then show ^¬ that the xth cop that comes from the yth spinning position, an error signal has occurred.

When processing yarns on a winding machine 25 assigned to a ring spinning machine in the so-called composite, the cops 12 at the end of the ring spinning machine 1 are often converted in a conversion device 31 to other copellers 30, which are transported to the work stations 24 of the winding machine 25 by means of a further transport device 32. The copellers 30 with the cop sleeves spooled empty in the winding machine 25 run back to the transfer device 31 and are there again converted to the copellers 30 to be reclaimed to the ring spinning machine 1 by means of the transport device 27.

The conversion device 31 is generally equipped with a marking device 33 which, on data carriers provided on the copellers 30, for example in the form of optically readable bar codes 34, notes the serial number of the spindle 11 of the Rmgspmn-maschme 1, of which the m the order of the spindles supplied cops come from each. It goes without saying that the spindle numbers can also be held on data carriers which are arranged on the sleeves of the cops 12 or that electronically readable data carriers can also be used.

So that a faulty yarn-producing spinning position of the ring spinning machine 1 can be determined, the control device 20 can also automatically cause the number of the spindle in question to be read from the copeller or the head pulse and, for example, to be shown on a display of the control device. For this purpose, the work stations 24 of the spool scanners are equipped with devices (not shown in more detail) for reading the spool number recorded on a copeller 30 or the Kopshulse from which the processed cop originates. This gives the operator the opportunity, in particular the compacting device 14, of this work station of the ring spinning machine 1 check and restore their possibly faulty function.

It is of course also possible to use the control device 20 to generate an actuating signal from the error signal of the hairiness sensor 17 'and the spindle number and to forward it to the ring spinning machine 1, by means of which an arrangement, which is described in connection with the embodiment described above, is arranged at the addressed work station Match stop device 13 can be automatically released.

The failure of a compression device is a serious error on the one hand, but a comparatively rare error on the other hand. It is therefore sufficient in many cases not to constantly monitor all running yarns of a yarn-producing or a yarn-processing device such as a ring spinning machine or a winder by means of a hairiness sensor. For this purpose, it can be provided that a hairiness sensor 17 "patrols on an endless tension member 35 as indicated in FIG. 2 along the work stations of a ring spinning machine 1 or, as not shown, a winding machine 25, and the running yarns 18 or the cops 12 each briefly, but When scanning on the ring spinning machine 1, the assignment of an error signal to the particular job being scanned is readily given, and when scanning on the winding machine 25, devices must be provided which enable this assignment.

LIST OF REFERENCE NUMBERS

1 ring spinning machine

2 roving bobbins

3 roving 4 drafting system, 6, 7 pairs of rollers of the drafting system

8 ring spinning device

9 Thread guide 10 Ring bench 11 Spindle

12 cops

13 match stop device

14 compression device

15 suction lower roller 16 upper roller ', 17 "hairiness sensor

18 yarn

19 sensor line

20 control device 21 control line

22 signal line

23 warning lamp

24 workstations of the winding machine

25 winding machine 26 manifold

27 Transport device on the ring spinning machine

28 deflection rollers

29 Endless tension member for copellers 30 copellers

31 transfer device

32 Transport device in the winding machine 33 Marking device on the setting device

34 barcode

35 Endless tension member for hairiness sensors

Claims

Process for the production of compacted yarn and device therefor

Patent claims

1. A process for the production of compacted yarn, characterized in that the effect of compacting is checked by automatically checking the hairiness of the yarn produced and is monitored by automatically monitoring the exceeding of a predetermined limit value for the hairiness.

2. The method according to claim 1, characterized in that the hairiness of the yarn produced is detected with respect to the frequency of protruding fibers with greater protruding length.

3. The method according to claim 1, characterized in that the checking and monitoring of the hairiness on the yarn is carried out.

4. The method according to claim 3, characterized in that the checking and monitoring of hairiness takes place directly at the spinning position. A method according to claim 3, characterized in that the checking and monitoring of the hairiness takes place in a subsequent processing step of the yarn produced.

Method according to claim 1, characterized in that the checking and monitoring of the hairiness takes place on the cop.

Method according to Claim 1, characterized in that a signal is emitted when a predetermined limit of hairiness is exceeded.

8. The method according to claim 7, characterized in that a warning device is switched on with the signal emitted, by means of which attention is drawn to the error that has occurred.

9. The method according to claim 7, characterized in that the defective spinning station is automatically stopped with the signal emitted.

10. Device for producing compacted yarn, characterized in that it has a hairiness sensor (17) for detecting the hairiness of the yarn produced (18) and a control device

(20) for determining whether a predetermined value has been exceeded

Limit of hairiness and to give a signal at

Has exceeded the limit.

11. The device according to claim 10, characterized in that the hairiness sensor (17) is set up for detecting yarns protruding from the fiber sections of certain length classes.

12. The device according to claim 10, characterized in that the control device (20) for determining the exceeding of a predetermined limit of hairiness for

Detect the yarn (18) or the cop produced

(12) protruding fiber sections of certain length classes is set up.

13. The device according to claim 10, characterized in that the control device (20) with the spinning positions of the device (1) for producing compressed yarns is operatively connected such that an incorrectly operating spinning position can be automatically switched off by means of a signal emitted by the control device.

14. Device according to claim 10, characterized in that each spinning position of the device (1) for producing compacted yarns is equipped with a hairiness sensor (17).

15. The device according to claim 10, characterized in that a cops (12) handling device (27) one of the handled cops successively scanning hairiness sensor (17 ') is delivered.

6. Device according to claim 10, characterized in that one of the device (1) for producing compressed yarns (18) downstream, the yarn processing device (25) at least one hairiness sensor (17) is delivered and that means (33, 34, 20th ) are provided which allow a processed yarn to be assigned to a spinning station of the device for producing compacted yarns.

17. Device according to claim 10, characterized in that a hairiness sensor (17 ") guided along the work stations (24) of a yarn manufacturing or processing device (1, 25) is provided, by means of whose yarn (18) or cops (12 ) are briefly but always palpable for their hairiness.