DE2756937A1 - METHOD OF BLOW TREATMENT OF MULTIFILER YARNS ON A KNITTING MACHINE, DEVICE FOR CARRYING OUT THE PROCESS AND TREATED YARN - Google Patents

Description

Α3Κϋ21723 / 172 ^ 7ο ^ 6 9 3 7

Process for the purple treatment of multifilament yarns on a knitting machine, Apparatus for carrying out the process and treated yarn.

Akzo GmbH
Wuppertal

The invention relates to a method for blow treatment multifilament Yarns on a knitting machine, in particular a circular knitting machine , with a pressurized gaseous strövner.dan medium, whereby the yarns to be knitted in a Treatment zone between the supply bobbins and the needle cylinder be provided with loops and / or other deformations.

Such a method is per se from the magazine "Deutsche Textiltechnik" 21 (1971), Issue 7, page 440, right Column, Section 3.6. However, Ee was in Konur Extent has not yet been used because the practical difficulties involved in realizing it were considered too great.

Surprisingly, process conditions have now been found and confirmed by careful and extensive experiments, by which the described difficulties in implementation of the process described could be overcome. The inventive The method is characterized in that overpressure of the gaseous flowing medium, over-delivery rate and thread tension of the yarn are chosen so that the skidness, measured in the manner described below, at least 200 for A 0.6 mm and 10 for A 3.5 mm, where A mm

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is equal to the distance between the center line of an M <_ beam and the nearest boundary line of the projection of the compact package in mm. In a preferred embodiment the skidness at A = 1.7 mm is at most Gc? :: .. "3 or the preferred embodiment is the overpressure of the gaseous flowing medium, in particular air, preferably ΰ, 5 to IO bar and especially 3 to 5 bar. At a advantageous embodiment of the method according to the invention is the speed with which the yarns in the Eshandlur-gszona are delivered, 5 to 40% and in particular 15 to 30% greater than the speed with which the zuarruT.enceblascr: e Yarn is withdrawn from the treatment zone. One A special effect can be achieved by the fact that the ratio of the delivery speed of the yarn into the treatment zone to Withdrawal speed of the yarn from the treatment zone is changed periodically according to a, preferably selectable, program.

According to the invention, particularly advantageous results are achieved when a yarn is processed whose individual filament edge has a more or less jagged cross-sectional shape, in particular a three-, four-, five-, six- or eight-armed or other non-round cross-sectional shape. The yarn according to the invention can also have individual hollow filaments. In a simple embodiment of the invention, only one raultifile yarn is treated in the treatment zone. According to the invention, special effect yarns result when two or more multifilament yarns are blown together in the treatment zone. The use of filaments with different shrinkage capacities is particularly advantageous. If two or more yarns are blown together, a very attractive knitted fabric can be achieved in that at least one of the yarns has a lower tension than the other yarns. The result is a core-sheath yarn in which the yarn supplied with the lower tension is

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beautiful Mar.tel forms. Appropriate choice of thread tension The core thread may also contain a few loops. The Schiaufigkcl-i b.r. /. however, the number of loops in the core yarn lies i inside considerably below that of the mantle thread.

A knitted fabric with a particularly attractive appearance can be achieved according to the invention by the presentation of false twist, Compression body, gear crimping or by a c: nd2re l direct kind of crimped yarn.

It is advantageous if a multifilament yarn with an essentially latent crimp is fed to the treatment 2Cne. The pattern can be generated, for example, by puckering the edges or by creating a temperature gradient along the cross-section of the individual strips through brief asymmetrical heating and cooling of the yarn. Advantageously verv / encbar are for example also bi- or Mehrkorriponenten-FüiG.i -... Lt side-by-side or asymmetric sheath-core structure. In the manufacture of the core Ma .-. TGl yarn described above, according to the invention, yarns with latent crimps can also be used as sheath threads, the filaments of which have a non-round cross-section Different multifilament yarns, for example those made of polyester or polyamide or combinations thereof, are suitable.

The invention also relates to knitted and warp-knitted articles produced by the method according to the invention. Mach leaving the knitting machine undergoes da-s knitting products some known per se Uachbehandlungsstufen such as washing, dyeing and stabilizing at elevated temperature. The latent crimping that may be present is preferably visible and, together with the shrinking process, results in a knitted or knitted material

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BATH ORIGINAL

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ir it. surprisingly advantageous properties, for example a very good grip. Invention device vrerde.i dia beoton '.ιeel.nisr.ü / uit knitwear of the well-known Wevenit or Intc-ricck type.

In sin. insofar as they result from the interruption of the texturing process. Beiir. Stopping the circular knitting machine or de3 drive for the needle cylinder is erfir.dungsgeir.äß continue to maintain the supply of the gaseous under excess pressure stcovia ^ n medium for a short period of time.

The period of time between turning off the cylinder drive and shutting off the pressurized gas supply is chosen according to the invention: g.in; iß v / o that it corresponds to the time that the needle cylinder needs, • ac. to come to a standstill. It can see about 1 to 10. and preferably 2 to 5 seconds. be. In an advantageous embodiment, after the drive motor for the needle cylinder has been switched off, the supply of the compressed gas is reduced according to a preferably selectable program before the final shut-off takes place. The reduction can be carried out continuously or gradually. According to the invention, it is very effective to proceed in such a way that the expiring needle cylinder itself controls the reduction in the supply of pressurized gas according to its decreasing speed via corresponding, known connecting means.

The invention further relates to a circular knitting machine for performing the described method with a device with receiving devices and guides for the yarn to be processed, 31as-

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Performances of a known type, a supply line for the pressurized gaseous flow medium, further a needle cylinder with a Usual number of systems, for example 24 or 48, ur.d Means for winding up the machine frame provided with the knitted tube, which is characterized by means of a type known per se, UT. the supply of the compressed gas after the drive has been switched off for the needle cylinder for a selectable delay time ν: .ii:? r to be maintained before the cordon takes place. Erf: .ndu: "ij. ^ Gerüi £ is for example a so-called Zeitri.-Isis usable.

T-: e ± a preferred embodiment, the needle cylinder or dü-T-isn drive ve is connected to the shut-off devices of the compressed gas lines by means of suitable connections containing appropriate control elements. According to the invention, these control elements work according to an adjustable program. The shut-off of the compressed gas supply should, if possible, only take place when the needle cylinder has run out.

An essential advantage of the method according to the invention results in such a way that smooth yarn can be presented, so that there is a risk of malfunctions due to process difficulties practically becomes very low even at high work speeds.

Based on the attached schematic drawings, the Invention explained in more detail. Eb shows

1 shows the scheme of a circular knitting device,

2 shows a somewhat modified form of the circular knitting device,

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BATH ORIGINAL

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3 shows the circuit diagram of a device for measuring the yarn slope,

Fig. 4 and Fig. 5 an illustration of the process of yarn loop measurement,

6 Schiaufigkeit as a function of the measuring distance A and

7 shows a yarn section according to the invention with typical Appearance.

First, the circular knitting device according to FIG. 1 will be described. On the circumference of the rotating needle cylinder 1, 24 locks are evenly distributed. The cylinder 1 rotates in the direction indicated by arrow 2. In the embodiment shown, two yarns 3 and 4 are fed to each system; for the sake of clarity, however, only the yarns for a needle lock are shown.

A smooth feed yarn 3 is drawn from a feed bobbin 5 and runs over a thread guide 6 and a delivery device 7 in the form of a conventional delivery godet with a separating roller. On its way to the needle lock, the yarn 3 continues over a thread guide 8, an air texturing device 9 that simultaneously exerts a tensile force on the thread, and a thread guide 10. For each system there is a special thread guide 8 and also a blowing unit 9 on the frame of the knitting machine intended. The blowing devices 9 can correspond approximately to the type described in GB-PS 825,327. In the same way, the yarn 4 is also guided to the air texturing device 9 via the yarn guide 11 , the delivery mechanism 12 and a second yarn guide. In the blower 9, the yarns 3 and 4 are blown together to form a Kernmantelgarη. The result is determined by the choice of thread tension and

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the extent to which the yarn has been passed on.

The thread speeds must be adjusted by an adapted selection of the delivery speeds of the delivery mechanisms 7 and 12 that the tension in the sheath yarn 4 is lower than in the core yarn 3 or the over-delivery rate of the sheath yarn is higher is than that of the core yarn.

As already mentioned, the result is a very appealing one End product, if a multifilament polyester thread is used as the sheath or sheath yarn, the one preferably through asymmetric heating or cooling achieved latent curl having. The resulting knitted tube 15 is pulled off the needle cylinder in a known manner and wound up, whereupon - if necessary later - the post-treatment takes place in the usual way.

FIG. 2 shows an embodiment of the device according to the invention that is somewhat modified compared to the preceding one. A rotating one Needle cylinder 200, which is operated by a motor 10000, has 24 needle locks distributed on its unifang are. The direction of rotation of the cylinder is indicated by the arrow 300. Two yarns 400 are used for each of the locks and 500 led. Here, too, only the yarn feed for one system is shown for clarity. A smooth master yarn is withdrawn from the supply bobbin 600 and runs over a thread guide 700 and a delivery mechanism 800, further over a thread guide 900, by an air texturing device 100, which simultaneously exerts a tensile force on the thread, and a thread guide 110. A special thread guide 900 is provided on the machine frame for each needle lock, and one for each lock Blowing unit 100.

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50 is performed in the same way as described above. In the blowing unit 100, the yarns 400 and 500 are blown together and form a core-sheath yarn. The loops are mainly in the polyester thread 500 which forms the sheath generated, for example, has a latent curl of a known type. The knitted tube 160 is known in FIG Wound way and post-treated in a later stage in the usual way.

Between the drive motor 100 for the needle cylinder 2OO and the air texturing device 100 is provided with a control arrangement which is shown schematically by the dashed line 170 is indicated. This is used to ensure that the compressed gas supply is still adequate after the drive motor 1000 has been switched off Maintain time before it is locked in the manner described above. It goes without saying that for Each needle lock is provided with an elastic unit 100 and consequently the drive motor 1000 with all of these blowing devices identical means 170 must be connected.

The delay between switching off the drive motor 1000 and shutting off the air supply to the blower units 100 using the controller 17O is of particular importance when at relatively high operating speeds (for example yarn speeds of 100 to 600 meters per minute) correspondingly large amounts of air per unit of time are needed, or when the blowing treatment is used on only one multifilament yarn. Because of its large mass and its relatively high speed, the run-down time of the needle cylinder 200 is relatively long. Because of the high air currents Maintaining the air supply when the needle cylinder 200 is at a standstill can not only cause streakiness in the

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Knitwear, thread breaks can also occur. In this case, the processing of a single multifilament yarn at high speeds would not be feasible, since the machine would have to be re-threaded after each standstill.

Many forms of variation are possible within the scope of the invention. For example, a buffer container can be arranged in the compressed gas line, from which the lines to the blower devices be guided. If, at the same time as the drive motor is switched off, an upstream of the buffer tank is installed If the valve is closed, the blower devices will continue to be supplied with pressurized gas for a time depending on the dimensions of the buffer container with decreasing pressure. In an approximately modified embodiment, the valve in front of the buffer container can be closed with some delay via a time relay and some time later another valve behind the buffer tank is closed, so that a simple way programmed shutdown of the blowers is achieved. Finally, a valve controlled by the speed of the outgoing needle cylinder can be built into the air line, whereby the control can be done either directly dependent or by a special program.

FIG. 3 schematically shows a device for measuring the loopiness of the yarn. As can be seen from the figure, there is light a Lcmpe 16 with the help of a converging lens 17 into a thin one Transformed beam 18 of parallel light. The diameter of the light beam is about 0.5 mm. The light beam 18 hits a phototransistor 19. This sends an electrical signal dependent on the intensity of the light it collects the end. Between the lens 17 and the phototransistor 19 runs

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the yarn 20, the real running of which is to be determined. the Axes of the yarn 20 and the light beam 18 cross each other at right angles, the distance between the yarn surface and the light beam is adjustable.

The yarn 20 is moved at a speed of 30 ra / rain. A protruding yarn filament that crosses the light beam guides to a change in the electrical signal. These changes are amplified accordingly in the amplifier 21 and in the electronic counter 22 counted. The Schiaufigkeitsmeßgerät is known in principle and in the usual way with a Adjustment button 23 for adjusting the light intensity, a pilot lamp 24, an adjustment switch 25, an amplifier 26, an amplifier 27 and a light meter 28 are provided.

The distance between the surface of the compact package and the light beam can (in a manner not shown) through a micrometer screw that is part of the thread guide system, can be set. To do this, start where the center line of the package and the light beam intersect. This setting is reached when the intensity of the signal generated by the light reaches its minimum value. With the help of Microreceter screw is then the desired distance A between the center line of the light beam and the boundary of the yarn set. The position of the line of movement of the package can be determined with the help of a projection microscope (for example 125 times Magnification) can be determined by measuring the thread diameter. For this purpose, for example, 25 measurements are carried out and then determined the mean value from this.

The loop yarn to be examined is attached to a slide (2.5 × 7.5 cm) under a tension of 3 cN (the same as in the loop measurement device) and attached at the ends so that at least 5 cm remain free between them. All in all

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five such specimens are made. After that, for each; r. Use the projection microscope to prepare the preparation at five different Make the core diameter of the yarn measured at intervals of one cn. The compact yarn package is used as the yarn core 29 according to FIG.

As from the previous description of the Skiaufigkeitsnesser becomes clear each time the distance is adjusted A counts only those loops or filament parts that are detected by the 0.5 mm thick measuring light beam, that is lie in a range A - 0.25 mm. The measuring process is described in more detail with reference to FIGS. There is thread in both shown in cross section and the light beam 18 in longitudinal section. The compact package is with 29 and some from this protruding loops are denoted by 30. The contact line 31 identifies the aforementioned edge of the kcrioaktan package, pos. 30 is the center line of the light beam 18. Figures 4 and 5 are not to scale and differ only in the differences in distance A. FIG. 4 is intended to illustrate the measuring distance A equal to 0.6 mm, and FIG. 5 to illustrate the distance A equal to 1.7 mm. As can be seen where A is equal to the distance between the center line 32 of the measuring light beam and the edge 31. The measuring area, in the direction of the distance A measured is, as already mentioned, 0.5 mm. If counting or not counting a loop that ends within this range depends on the strength of the loop it creates electrical signal eb. The number N of counted loops per 5 m of yarn are in the description and claims as looping designated; For example, N is the mean of five measurements. The slope N depends on

a) the size of the loops protruding from the compact package and the measuring distance λ;

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b) the total number of loops per unit length of yarn; b) the shape of the loops.

With the measurement method described, the number is not of the loops per se, but only the part that intersects the measuring light beam 18 is counted. In this respect, "Schiaufigkeit N "and" Number of loops "not identical - but because the statistical distribution of the loops on the surface of the yarn can be safely assumed to be the same on all sides, the result is a representative value for the skiing ability. The loopiness can be before or after the knitting process to be eaten. In Fig. 6, the relationship between the reference distance A and the number of loops registered is at two polyester filament yarns drawn from fabrics produced by the method according to the invention are shown. It will It is clear that - which was to be assumed - the loopiness increases sharply with decreasing distance A.

Curve I applies to a kernmantle yarn with a smooth multifilament Polyester yarn as the core and one that is also smooth, but through asymmetrical heating latent crimped multifilament yarn as a sheath. At A «0.6 mm was N« 360; at A = »1.7 mm it was N much smaller and smaller than 50 for each individual measurement, while with A = 3.5 mn the value for N is always below 10 lay. Curve II applies to a core sheath yarn in which the core and sheath each consisted of a smooth multifilament polyester yarn “At A = 0.6 mm it was N 950, at A = 1.7 mm the result N o 30, while at A «3.5 mm N was less than 10.

An attractive piece of knitting was made as an example. The core-sheath material processed here indicated as the core dtex 76 f 24 polyester yarn with a round filament cross-section, as a jacket a dtex 50 f 24 polyester yarn, semi-matt on, with

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latent curling due to asymmetrical heating, its Individual filaments had a square hollow cross-section. The feed rate to the blower was for the Core yarn 200 m / min, for the sheath yarn 250 m / min. From the blower the blown kernmantle yarn ran to the needle cylinder 1 at a speed of 200 m / min the knitting machine. In another example, another very attractive knitted product was made, namely all other things being equal with the difference that dia Filaments of the sheath yarn Hollow threads with a square cross-section was.

The framework of the present invention allows a wide variety of modification forms to be made.

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Claims (31)

A3KU21723 / 1726 DT claims 1. Method for the blow treatment of multifilament yarns on a knitting machine, in particular a circular knitting machine a pressurized gaseous flowing medium, the yarns to be knitted initially in a Treatment zone between the supply bobbins and the Nadslzylindcr are provided with loops and / or other deformations protruding from the yarn surface, characterized in that that the overpressure of the gaseous medium, overdelivery rate and thread tension of the yarn are chosen so that the loop N, determined by the in the description explained measuring method, over a thread length of at least 5 m 200 for A «0.6 mm and not more than 10 for A = 3.5 mm, where A is the distance between the center line of a measuring light beam and the nearest boundary line of the projection of the compact package in mm. 2. The method according to claim 1, characterized in that for A »1.7 mm the looping is not higher than 50. 3. The method according to claim 1 and 2, characterized in that the excess pressure of the gaseous flowing medium, in particular air, is 0.5 to 10 bar and preferably 3 to 5 bar. 4. The method according to one or more of the preceding claims, characterized in that the speed at which the yarns are conveyed to the treatment zone, 80982 ^ / 0778 I. - 2 - A3KU21723 / 1726 DT r / 56337 5% to 40% and especially 15% to 30% higher than that Speed / with which the blown yarn is blown out the treatment zone is withdrawn. 5. The method according to claim 4, characterized in that the Ratio of the delivery speed of the yarn to the treatment zone to the withdrawal speed of the yarn from the treatment zone is changed periodically in accordance with a preferably selectable program. 6. The method according to one or more of the preceding claims, characterized in that the blow treatment takes place at any location between the supply reel and the needle cylinder he follows. 7. Seduction according to one or more of the preceding claims, characterized in that the yarn Eir.2elfila1r.ente contains a rugged, undulating, multilobal, in particular have three-, four-, five-, six- or eight-armed cross-section or another non-round cross-section . 8. The method according to one or more of the preceding claims, characterized in that the yarn is single filaments contains, which are hollow fibers. 9. The method according to one: n or more of the preceding claims, characterized in that only one multifilament yarn is treated in the treatment zone. 10. The method according to one or more of claims 1 to 8, characterized in that two or more multifilament yarns are blown together in the treatment zone at the same time. 80982 ^ / 0778 " ³ ~ I - 3 - A3KU21723 / 1726 DT 11. The method according to one or more of the preceding claims, characterized in that the supplied yarns contain individual filaments which have different shrinkage properties exhibit. 12. The method according to one or more of the preceding claims, characterized in that at least one of the two or more yarns fed to the treatment zone has a lower yarn tension than the other yarns. 13. Processor according to one or more of claims 1 to 12, characterized in that at least one of the yarns supplied to the treatment zone is a multifilament yarn, v / elches having a false twist, stuffer box, gear crimp or some other type of direct crimp . 14. The method according to one or more of the preceding claims, characterized in that at least one of the yarns supplied to the treatment zone has a substantially latent crimp . 15. The method according to claim 14, characterized in that the latent crimp is generated by temporarily generating a temperature gradient over the cross section of the individual filaments. 16. The method according to claim 14, characterized in that the individual filaments of the yarns or two or more component yarns in side-by-side or asymmetric sheath-core arrangement. - 4 80982 ^ / 0778 I. - 4 - A3KU21723 / 1726 DT 17. The method according to claim 7 and 12, characterized in that the yarn, the single filament of which does not round one Have cross section that forms the sheath yarn. 18. The method according to claim 12, characterized in that the yarn ir-it latent crimp forms the sheath yarn. 19. Method of treating multifilament yarns on a circular knitting machine with a stream of a gaseous stripping medium under excess pressure according to one or more of the preceding claims, characterized in that after the knitting machine or the drive for the needle cylinder to supply the pressurized gaseous flow medium for a delay period is maintained. 20. The method according to claim 19, characterized in that the delay time between switching off the needle cylinder drive ^ .id to shut off the compressed gas supply of the time, which the needle cylinder needs to come to rest is adjusted. 21. The method according to one or more of claims 19 and 20, characterized in that the delay time is 1 to 10 seconds and preferably 2 to 5 seconds. 22. The method according to one or more of the preceding claims, characterized in that after switching off the drive for the needle cylinder, the supply of the compressed gas is reduced according to a preferably selectable program. -δ- Ι 80982 ^ / 0778 I. - 5 - A3KU21723 / 1726 DT 23. seducer according to claim 22, characterized in that the pressure gas supply is reduced in stages. 24. The method according to one or more of the preceding claims, characterized in that after switching off dos: \ 'needle cylinder drive, the reduction in the gas supply is controlled by this depending on the decreasing speed of the needle cylinder . 25. Strickstück ger.äß method according to claim 1 to 24, characterized characterized as being of the Wevenitt type. 26. Knitted piece according to the method according to claim 1 to 24, characterized in that it is of the interlock type. 27. Circular knitting machine for carrying out the process according to the invention, which has a frame that is equipped with receiving and guiding devices for the yarns to be presented, blowing devices connected to a compressed gas line, a needle cylinder with drive and a variety of needle locks and means for winding up the knitted tube. π is characterized by means of a type known per se / in order to maintain the supply of the compressed gas after switching off the drive for the needle cylinder for a selectable delay time before the shut-off takes place. 28. Circular knitting machine according to claim 27, characterized in that the means causing the delayed shutdown of the gas supply contain a time relay. 29. Circular knitting machine according to claim 27 or 28, characterized in that the needle cylinder or its drive means 80982 ^ / 0778 J. - 6 - A3KU21723 / 1726 DT (jeν- ? i] r.ster, corresponding control element containing connection ".;en" dt is connected to the shut-off devices of the compressed gas lines. 30. Circular knitting machine according to claim 29, characterized in that that the control elements work according to a selectable program. 31. Circular knitting machine according to one or more of claims 27 to 30, characterized in that in the feed line to A buffer container is arranged for the Blavorrichtungen. 80982 ^ / 0778 I.