EP1608804B1 - Texturing nozzle and method for texturing a filament yarn - Google Patents

Abstract

A process imparts a texture to a constant feed of yarn as it passes along a widening nozzle under the influence of supersonic pressurised air at more than 4 bar. The channel terminates in a further widening flare of more than 10. Also claimed is a commensurate nozzle with an inlet to a widening conical channel that terminates in a further flare of between 10 and 40. Compressed air is introduced to the channel from the side at an angle of more than 50 to the longitudinal axis.

Description

Technical area

The new invention relates to a method for texturing endless yarn by means of a texturing, with a continuous yarn channel is blown into the compressed air with more than 4 bar in Garntransportrichtung, said at the exit end of the yarn channel with an expansion angle greater than 10 °, preferably flared for the Generation of a supersonic flow. The invention further relates to a texturing for texturing endless yarn with a continuous yarn channel with an inlet end, a central, preferably cylindrical portion with an air injection bore and an outlet end with an expansion angle greater than 10 °.

State of the art

The term "texturing" is partly understood to mean the refinement of spun filament bundles or the corresponding continuous yarns with the aim of giving the yarn a textile character. In the following description, the term "texturing" is understood to mean the production of a large number of loops on individual filaments or the production of loop yarn. An older solution for texturing is in the EP 0 088 254 described. The continuous filament yarn is fed to the yarn guide channel at the entrance end of a texturing nozzle and textured at a trumpet-shaped exit end by the forces of supersonic flow. The middle section of the yarn guide channel is cylindrical throughout its length with a constant cross section. The entry is slightly rounded for easy insertion of the untreated yarn. At the trumpet-shaped outlet end is a guide body, which takes place between the trumpet shape and the guide body looping. The yarn is supplied to the texturing nozzle with a great deal of tradition. The tradition is needed for loop formation on each individual filament, resulting in a titer increase at the exit end.

The EP 0 088 254 was based on a device for texturing at least one continuous filament consisting of a plurality of filaments with a nozzle fed with a printing medium, comprising a yarn guide channel and at least one feed for the printing medium which opens into the channel in the radial direction. The generic nozzle had an outwardly widening outlet opening of the channel and a projecting into the latter, with the same an annular gap forming spherical or hemispherical guide body. It has been recognized that with textured yarns, maintaining yarn properties during and after the finishing process is an important criterion for the utility of such yarns. Further, the degree of blending of two or more yarns and the individual filaments of the textured yarns is also essential for achieving a uniform appearance of the goods. Stability is used as a concept of quality. To determine the instability I of the yarn yarn strands are formed with four turns of one meter circumference on a reel, as explained by means of a multifilament yarn on polyester with a titer 167f68 dtex. These strands are then loaded for one minute with 25 cN, and then the length X is determined. This is followed by a charge of 1250 cN for one minute. After relieving, after one minute the strand is again loaded with 25 cN and after a further minute the length y is determined. This gives the value of instability: $$\mathrm{I}\mathrm{=}\frac{\mathrm{Y}\mathrm{\cdot }\mathrm{X}}{\mathrm{X}}\mathrm{\cdot }\mathrm{100}\mathrm{\%}$$

The instability indicates what percentage of permanent strain is caused by the applied load. Of the EP 0 088 254 It was the object to provide an improved device of the type described, with which an optimal texturing effect can be achieved, which ensures a high stability of the yarn and a high degree of mixing of the individual filaments. As a solution it has been proposed that the outer diameter of the convexly curved outlet opening of the channel is at least equal to 4 times the diameter of the channel and at least equal to 0.5 times the diameter of the hemispherical guide body (5). The optimum results were production speeds in a range of 100 to over 600 m / min. found. Interestingly enough, the notifying party succeeded in successfully marketing appropriate nozzles over a period of more than 15 years. The quality of the yarn produced with it was judged to be very good over a period of 1 ½ decades. Increasingly, however, the desire for an increase in performance was expressed. Of the Applicant succeeded with the solution according to EP 0 880 611 a massive performance increase to well over 1000 m / min. Yarn transport speed. The main idea for the increase in performance was an intensification of the flow conditions in the expanding supersonic channel, ie in the zone in which the loop formation takes place. As a special test criterion, the yarn tension was recognized at the exit from the texturing nozzle. Many series of tests revealed that according to the solution EP 0 088 254 the yarn tension after about 600 m / min. Yarn transport speed drops sharply. This is ultimately the explanation for the power limitation of these nozzle types.

The proposal of EP 0 880 611 with the intensification of the flow in the supersonic channel gave an unexpected increase in the yarn tension, which allowed the transport speed to over 1000 m / min. to increase. The quality of the yarn processed at that time was initially judged to be the same, if not better, even at the highest transport speeds. However, the practice subsequently showed surprises in that in many applications the yarn quality did not meet the desired requirements.

The new invention has now been based on the object to develop a method and a texturing, which increases performance, in particular to well over 1000 m / min. permitting, however, results in highest possible yarn qualities in all applications.

Presentation of the invention

The inventive method is defined in the subsequent claim 1.

• das Öffnen des Garnes und
• das Texturieren des Garnes

aufeinander optimal abgestimmt werden müssen. Mehrfach wiederholte Versuche zeigten, dass bei der Lösung gemäss EP 0 088 254 die Begrenzung in der Texturierzone liegt und deshalb eine Steigerung der Garnöffnung nur Nachteile bringt. Aus dem Gebiet der Garnverwirbelung ist bekannt, dass der Garnöffnungseffekt am grössten ist bei einem Einblaswinkel von 90°. Das Ziel der Verwirbelung ist, in dem Garn regelmässige Knoten zu bilden. Als Beispiel für die Verwirbelung wird auf die DE 195 80 019 verwiesen. Beim texturierten Garn dürfen dagegen unter keinen Umständen Knoten gebildet werden. Es muss ein Grenzbereich für den Einblaswinkel für die beiden grundsätzlich unterschiedlichen Verfahren der Knotenbildung und der Schlingenbildung geben. Es war allerdings noch nicht möglich, diese Grenzen zu bestimmen. Bis zur Zeit wird ein Bereich für den Einblaswinkel von 49°, jedoch kleiner als 80°, vorzugsweise 50° bis etwa 70° angenommen. Die obere Grenze konnte noch nicht abschliessend ermittelt werden. Der Garnkanal weist einen mittleren, vorzugsweise zylindrischen Abschnitt auf, welcher in Transportrichtung ohne Sprung in die konische Erweiterung übergeführt ist, wobei die Druckluft mit einem genügenden Abstand zu dem konisch erweiterten Überschallkanal in den zylindrischen Abschnitt eingeblasen wird.With all previous investigations, it could only be confirmed that the texturing nozzles according to EP 0 088 254 determined data is the optimal injection angle for the treatment air at 48 °. Any increase above 48 ° only worsened the texturing. It is also on the large-scale underruns of A. Demir in the "Journal of Engineering for Industry" of February 1990 (Vol. 112/97 ). The author of the article had the opportunity to test the essential parameters with many test series. Nozzles with 30 °, 45 ° and 60 ° inlet angles were investigated. The nozzles with 60 ° blowing angle were in some ways worse, not least because at 60 ° a large part of the energy on the counter-wall occurs and is destroyed. This was scientifically confirmed, which empirically in the context of the development of the texturing according to EP 0 088 254 found and was no longer doubted in the episode. In the development of the newer nozzle shape according to EP 0 880 611 There was no reason to doubt the long-standing belief that the range from 45 ° to 48 ° inlet angle was optimal. This feature also found its way into the description of the solutions according to EP 0 880 611 , As already stated, in the search for an improvement in yarn qualities, among other things, a new start was made with regard to the influence of the injection angle. As a complete surprise, it was found that the enlargement of the injection angle with nozzles according to EP 0 880 611 already brought an unexpected increase in the quality of the textured yarn in the first series of tests. The inventors subsequently recognized that the two process zones,

• opening the yarn and
• the texturing of the yarn

must be optimally matched to each other. Repeatedly repeated experiments showed that in the solution according to EP 0 088 254 the limitation in the texturing zone and therefore an increase in the yarn opening brings only disadvantages. From the field of yarn swirling it is known that the yarn opening effect is greatest at an injection angle of 90 °. The goal of swirling is to form regular knots in the yarn. As an example of the turbulence will be on the DE 195 80 019 directed. On the other hand, textured yarns must not be knotted under any circumstances. There must be a borderline for the injection angle for the two fundamentally different methods of knot formation and looping. However, it was not yet possible to determine these limits. Until the time, a range for the Einblaswinkel of 49 °, but less than 80 °, preferably 50 ° to about 70 ° is assumed. The upper limit could not yet be finally determined. The yarn channel has a central, preferably cylindrical portion, which is transferred in the transport direction without jumping in the conical enlargement, wherein the compressed air is injected with a sufficient distance to the conically expanded supersonic channel in the cylindrical portion.

• Bei Texturierdüsen mit intensivierter Überschallströmung gemäss EP 0 880 611 konnte bei jedem Garntiter eine Qualitätsverbesserung erzielt werden, wenn der Einblaswinkel über 48° gesteigert wurde.
• Die Qualitätssteigerung beginnt mit einem markanten Anstieg bei einer Vergrösserung des Winkels über 48°.
• Bei Einblaswinkeln grösser 52°, teils bis 60° und sogar 65°, bleibt die Garnqualität erstaunlich konstant. Der optimale Einblaswinkel ist jedoch auch abhängig von dem Garntiter.

The experiments in connection with the new invention brought three new insights:

• For texturing nozzles with intensified supersonic flow according to EP 0 880 611 At each yarn titer, a quality improvement could be achieved if the inlet angle was increased above 48 °.
• The increase in quality begins with a marked increase in an increase in the angle over 48 °.
• With injection angles greater than 52 °, sometimes up to 60 ° and even 65 °, the yarn quality remains surprisingly constant. However, the optimum blowing angle is also dependent on the yarn titer.

It is therefore proposed to set the injection angle as a function of the yarn quality, in particular of the yarn denier in the range of 49 ° to 80 °, preferably 50 ° to 70 °. The advantages of the new invention could be utilized with texturing nozzles with only a single bore, through which the compressed air is injected at an angle greater than 49 ° or 50 °. Preferably, however, the compressed air is blown over three circumferentially offset by 120 ° holes in the yarn channel. It is crucial in any case that the yarn opening intensified by blowing the compressed air into the yarn channel, but a knot formation is avoided in the yarn.

The texturing nozzle according to the invention is characterized in that the compressed air for intensifying the yarn opening is blown into the yarn duct at an injection angle of more than 48 °, preferably more than 50 °. Preferably, the Lufteinblasstelle is arranged in the cylindrical portion at a distance from the conical enlargement, wherein the distance corresponds at least approximately to the diameter of the yarn channel. According to the current state of knowledge, the length of the two process stages, opening and texturing, are at nozzles according to the older one EP 0 088 254 too short. This is one of the reasons for the limited transport speed with a nozzle type according to the older solution.

1. 1. Die Öffnung des Garnes einerseits sowie die Texturierung des Garnes andererseits müssen je für sich optimiert werden;
2. 2. zur Optimierung der beiden total unterschiedlichen Funktionen müssen diese örtlich getrennt,
3. 3. jedoch kurz nacheinander durchgeführt werden, derart, dass der Öffnung unmittelbar die Texturierung folgt, bzw. dass die Beendigung des Garnöffnungsvorganges unmittelbar in die Texturierung übergeht.

The new invention brought different insights:

1. 1. The opening of the yarn on the one hand and the texturing of the yarn on the other hand must be optimized for each;
2. 2. to optimize the two totally different functions, they must be separated locally,
3. 3. However, be carried out in quick succession, such that the opening immediately follows the texturing, or that the termination of the Garnöffnungsvorganges passes directly into the texturing.

At least the central, cylindrical section and the conically widened outlet section of a texturing nozzle are formed as part of a nozzle core. The nozzle core is preferably formed as an insert in a texturing nozzle head and made of a material made of wear-resistant material, in particular ceramic.

Particularly advantageously, the nozzle core is designed as a removable core, such that a nozzle core with optimal internal dimensions and inlet angles can be used. This makes it possible, for example, to replace an existing nozzle core of the prior art with a few manipulations and to use all the advantages of the new invention. At the outlet end of the conically widened portion, as in the prior art, a guide body is arranged, which can be delivered at least until close to the conically widened outlet section. Thus, another contribution to the consistency of the quality of the yarn can be achieved. The Texurierdüse is advantageously formed as part of a texturing, wherein the air distribution is arranged on three Lufteinblasbohrungen in the texturing. In the consequence becomes on the EP 0 880 611 Reference is made to what basis and starting point for the new invention, as far as the process step texturing is concerned.

• Bei der Anwendung eines für den höheren Machbereich ausgestalteten Überschallkanales tritt bei gleicher Produktionsgeschwindigkeit eine qualitative Verbesserung der Texturierung ein, im Vergleich zum älteren Stand der Technik.
• Testversuche mit einzelnen Garntitern wurden bis zu einer Produktionsgeschwindigkeit von 1'000 bis 1'500 m/min. durchgeführt, ohne Zusammenbruch der Texturierung.
• Messtechnisch fiel sofort auf, dass die Garnspannung im Durchschnitt um gegen 50 % gesteigert werden konnte. Der gesteigerte Wert blieb zudem über einen grossen Geschwindigkeitsbereich von z.Bsp. 400 bis 700 m/min. nahezu konstant.
• Es hat sicher ferner gezeigt, dass auch in der Wahl des Speisedruckes der Druckluft ein wesentlicher Einflussfaktor liegt. Zur Sicherstellung der höheren Machzahlen wird in vielen Fällen ein höherer Speisedruck benötigt. Dieser liegt etwa zwischen 6 bis 14 bar, kann aber auf 20 und mehr bar gesteigert werden.

It was at the EP 0 880 611 recognized that the first key to the yarn tension quality is after the texturing die. Only if it is possible to increase the yarn tension, the quality can be improved. The breakthrough was made possible, as the flow of blast air jet was increased over the Mach 2 area. Many test series confirmed that not only improves the quality, but that the quality is negatively affected by an increase in production speed in a remarkably small amount. Even a slight increase in Mach number over 2 has already yielded significant results. The best explanation for the corresponding intensification of the Texturierporzesses is seen in the fact that the speed difference is increased immediately before and after the impact front, which directly affects the corresponding attack forces of the air on the filaments. The increased forces in the area of the impact front cause an increase in the yarn tension. By increasing the Mach number, the events on the shock front are directly increased. According to the invention, the law was recognized: higher Mach number = stronger impact = more intensive texturing. The intensified supersonic flow covers the individual filaments of the open yarn on a wider front and much more intensively, so that no slings can escape laterally beyond the impact zone of the impact front. Since the generation of supersonic flow in the acceleration channel based on the expansion, obtained by a higher Machbereich, so z.Bsp. instead of Mach 1.5 Mach 2.5, also an increase or nearly a doubling of the effective outlet cross-section. Various surprising observations could be made and confirmed in combination with the new invention:

• When using a supersonic channel designed for the higher Mach range, a qualitative improvement of the texturing occurs at the same production speed, in comparison to the older state of the art.
• Test runs with individual yarn titers were carried out up to a production speed of 1'000 to 1'500 m / min. performed without collapse of texturing.
• From a technical point of view, it immediately became apparent that the yarn tension could be increased on average by around 50%. The increased value also remained over a large speed range of z.Bsp. 400 to 700 m / min. almost constant.
• It has certainly also shown that in the choice of the feed pressure of the compressed air is a significant factor. To ensure the higher Mach numbers, a higher feed pressure is needed in many cases. This is about 6 to 14 bar, but can be increased to 20 and more bar.

The comparative experiments, state of the texturing according to EP 0 088 254 and new solution in the context of EP 0 880 611 The texturing quality is at least equal to or better than the texturing quality at lower production speed with a supersonic channel designed for the lower Mach range at a higher production speed. The texturing process is at air velocities in the front of over Mach 2, so z.Bsp. Mach 2.5 to Mach 5, so intense that almost all snares are recorded and integrated into the yarn, even at highest yarn throughfeed speeds. The generation of an air velocity in the high Machbereich within the acceleration channel causes the texturing to collapse up to the highest speeds no longer. Second, the whole filament composite is guided evenly and directly into the impact front zone within clear outer channel boundaries. The actual central criterion for the positive effect of the new invention is that the stability of the yarn is generally improved. If a yarn textured with the new solution is heavily loaded and released with a tensile force, then it can be seen that the texture, ie, firm knits and loops, remains almost unchanged. This is a crucial factor for subsequent processing.

In the acceleration channel, the yarn is pulled in by the accelerating air jet over the corresponding path, further opened and transferred to the directly subsequent texturing zone. The blown air jet is then passed to the acceleration channel without deflection through a discontinuous and strongly expanding section. It can be one or more yarn threads with the same or different tradition introduced and with a production speed of 400 to over 1200 m / min. textured. The compressed air jet in the supersonic channel is accelerated to 2.0 to 6 Mach, preferably to 2.5 to 4 Mach. The best results are achieved when the exit end of the yarn channel is delimited by a baffle such that the textured yarn is discharged approximately at right angles to the yarn path axis through a nip.

Particularly preferably, the blown air is also guided in the new invention according to the radial principle of the feed point in a cylindrical portion of the yarn channel immediately in an axial direction at an approximately constant speed up to the acceleration channel. As in the prior art of EP 0 880 611 can be textured with the new solution one or more yarn threads with a variety of traditions. The total theoretically effective expansion angle of the supersonic channel should be from the smallest to the largest diameter above 10 °, but below 40 °, preferably within 15 ° to 30 °. According to the currently available roughness values, an upper limit angle (total angle) of 35 ° to 36 ° has resulted with respect to the production of sera. In a conical acceleration channel, the compressed air is accelerated substantially steadily. The nozzle channel section directly in front of the supersonic channel is preferably made approximately cylindrical, with the delivery component being blown into the cylindrical section in the direction of the acceleration channel. The pull-in force on the yarn is increased with the length of the acceleration channel. The nozzle extension or the increase of the Mach number gives the intensity of the texturing. The acceleration channel should have at least a cross-sectional widening range of 1: 2.0, preferably 1: 2.5 or greater. It is further proposed that the length of the acceleration channel is 3 to 15 times, preferably 4 to 12 times larger than the diameter of the yarn channel at the beginning of the acceleration channel. The acceleration channel can be designed to be continuously widened in whole or in part, have conical sections and / or have a slightly spherical shape. However, the acceleration channel can also be formed finely graduated and have different acceleration zones, with at least one zone with high acceleration and at least one zone with small acceleration of the compressed air jet. The exit area of the Furthermore, the acceleration channel can be cylindrical or approximately cylindrical and the inlet area can be greatly expanded but extended to less than 36 °. If the boundary conditions for the acceleration channel were adhered to according to the invention, then the said variations of the acceleration channel proved to be almost equivalent or at least equivalent. The yarn channel then has a strongly convex, preferably a trumpet-shaped, yarn mouth extended by more than 40 °, following the supersonic channel, wherein the transition from the supersonic channel into the yarn channel mouth is preferably discontinuous. A decisive factor was found in that with a baffle, above all, the pressure conditions in the texturing space can be positively influenced and kept stable. A preferred embodiment of the texturing is characterized in that it has a continuous yarn channel with a central cylindrical portion into which the air supply opens, and in the thread running direction to the cylindrical portion immediately adjacent conical acceleration channel with an opening angle (α ₂ ) greater than 15 °, and a subsequent extension section with an opening angle (∂) greater than 40 °.

Brief description of the invention

die Figur 1

den Garnkanal in dem Bereich der Garnöffnungs- und Texturierzone gemäss der neuen Erfindung;

die Figur 2

schematisch die Garnspannungsprüfung beim Texturieren;

die Figur 3

einen erfindungsgemässen Düsenkern in grösserem Massstab;

die Figur 4

einen Düsenkern mit einem Prallkörper am Ausgang des Beschleuni- gungskanales;

die Figur 5

einen ganzen Düsenkopf mit Prallkörper;

die Figur 6

einen Vergleich von texturiertem Garn gemäss Stand der Technik mit der neuen Erfindung in Bezug auf die Garnspannung;

die Figuren 7a bis 7c und 8a bis 8c

Versuchsresultate in Bezug auf verschiedene Ein- blaswinkel, ausgehend von einer Düse des Standes der Technik mit einem Einblaswinkel von 48°;

die Figur 9

den Einsatz einer thermischen Stufe in Kombination mit der Texturierung;

die Figuren 10a

bis 10d den thermischen Einsatz über eine Galettenheizung.

The invention will now be explained with reference to some embodiments with further details. Show it:

the figure 1

the yarn channel in the area of the yarn opening and texturing zone according to the new invention;

the figure 2

schematically the yarn tension test during texturing;

the figure 3

a nozzle core according to the invention on a larger scale;

FIG. 4

a nozzle core with a baffle at the exit of the acceleration channel;

the figure 5

a whole nozzle head with baffle body;

the figure 6

a comparison of textured yarn according to the prior art with the new invention with respect to the yarn tension;

Figures 7a to 7c and 8a to 8c

Test results with respect to different injection angles, starting from a nozzle of the prior art with a 48 ° injection angle;

FIG. 9

the use of a thermal step in combination with texturing;

FIGS. 10a

to 10d the thermal application via a Galettenheizung.

Ways and execution of the invention

In the episode will now be on the FIG. 1 Referenced. The texturing 1 has a yarn channel 4 with a cylindrical portion 2, which also corresponds to the narrowest cross-section 3 with a diameter d at the same time. From the narrowest cross section 3 of the yarn channel 4 passes without jump in cross section in an acceleration channel 11 and is then expanded in a trumpet shape, the trumpet shape can be defined with a radius R. Due to the adjusting supersonic flow, a corresponding shock front diameter DA _E can be determined. Due to the impact front diameter DA _E , the detachment or tear-off point A ₁ , A ₂ , A ₃ or A ₄ can be determined relatively accurately. For the effect of the shock front is on the EP 0 880 611 directed. The acceleration range of the air can also be defined by the length ℓ ₂ from the point of the narrowest cross-section 3 and the tear-off point A. Since it is a true supersonic flow, it can be calculated about the air velocity.

The FIG. 1 shows a conical configuration of the acceleration channel 11, which corresponds to the length ℓ ₂ . The opening angle α ₂ is given as 20 °. The Ablössstelle A ₂ is located at the end of the supersonic channel, where the yarn channel in a discontinuous, strongly conical or trumpet-shaped extension 12 merges with a Öffnunswinkel ∂> 40 °. Due to the geometry results in a shock front diameter D _AE . As an example, the following conditions result: $$\mathrm{L}\mathrm{2}\mathrm{/}\mathrm{d}\mathrm{=}\mathrm{4.2}\mathrm{;}\mathrm{vd}\mathrm{=}\mathrm{330}\mathrm{m}\mathrm{/}\sec \mathrm{,}\left(\mathrm{<figure-callout\; id="1"\; label="Mach"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">Mach</figure-callout>}\mathrm{1}\right)\mathrm{;}\frac{\mathrm{DAE}}{\mathrm{d}}\mathrm{~}\mathrm{2.5}\mathrm{\to }{\mathrm{M}}_{\mathrm{DE}}\mathrm{=}\mathrm{Mach}\mathrm{3.2}$$

An extension of the acceleration channel 11 with a corresponding opening angle causes an increase in the shock front diameter D _AE . Immediately in the area of the shock front formation, the greatest possible compression shock front 13 with subsequent abrupt pressure increase zone 14 is formed. The actual texturing takes place in the area of the compression shock front 13. The air moves about 50 times faster than the yarn. Through many experiments it could be determined that the release point A ₃ , A _{4 can} also migrate into the acceleration channel 11, namely, when the feed pressure is lowered. In practice, it is now necessary to determine the optimum feed pressure for each yarn, wherein the length (ℓ ₂ ) of the acceleration channel is designed for the unfavorable case, so rather a little too long is chosen. With M _B , the center line of the injection bore 15 and M _{GK is} the center line of the yarn channel 4 and the intersection of M _GK and M _B denoted by SM. Pd is the location of the narrowest cross section at the beginning of the Acceleration channel 11, ℓ1 is the distance from SM and Pd, ℓ2 is the distance from Pd to the end of the acceleration channel (A4). Löff denotes approximately the length of the yarn opening zone, Ltex approximately the length of the yarn texturing zone. The larger the angle β, the more the yarn opening zone is increased in the backward direction.

The FIG. 2 shows an entire texturing head or nozzle head 20 with built-nozzle core 5. The unprocessed yarn 21 is fed via a delivery mechanism 22 of the texturing 1 and transported as a textured yarn 21 'on. In the exit region 13 of the texturing, there is a baffle 23. A compressed air connection P 'is arranged laterally on the nozzle head 20. The textured yarn 21 'runs at a transport speed VT via a second delivery mechanism 25. The textured yarn 21' is passed over a quality sensor 26, e.g. with the market name HemaQuality, called ATQ, in which the tensile force of the yarn 21 '(in cN) and the deviation of the instantaneous tensile force (sigma%) are measured. The measurement signals are fed to a computer unit 27. The appropriate quality measurement is a prerequisite for the optimal monitoring of production. The values are also an indicator of yarn quality. In the airblast texturing process, the quality determination is made more difficult in that there is no defined loop size. It is much easier to determine the deviation from the quality that the customer finds to be good. This is possible with the ATQ system, since the yarn structure and its deviation can be detected by a yarn tension sensor 26, evaluated and displayed by a single code, the AT value. A yarn tension sensor 26 detects as an analog electrical signal in particular the yarn tension after the texturing. From this, the AT value is continuously calculated from the mean value and the variance of the yarn tension measured values. The size of the AT value depends on the structure of the yarn and is determined by the user according to his own quality requirements. If the thread tension or the variance (regularity) of the thread tension changes during production, the AT value also changes. Where the upper and lower limits are concerned, it can be determined with yarn mirrors, knit or fabric samples. They are different depending on the quality requirements. The advantage of the ATQ measurement is that different types of disturbances from the process are detected simultaneously, eg. Uniformity of texturing, thread wetting, filament breaks, nozzle fouling, impact ball clearance, hot pin temperature, air pressure differences, POY mating zone, yarn template, etc.

In the episode will now be on the FIG. 3 Referring to a preferred embodiment of a whole nozzle core 5 in cross section in strong Enlargement shows. The outer fitting shape is preferably adapted exactly to the nozzle cores of the prior art. This applies above all to the critical installation mass, the bore diameter B _D , the total length L, the nozzle head height K _H and the distance L _A for the compressed air connections PP '. The tests have shown that the optimum injection angle β must be greater than 48 °. The distance X of the respective compressed air holes 15 is critical with respect to the acceleration channel. The yarn channel 4 has a yarn introduction cone 6 in the inlet region of the yarn, arrow 16. By directed in Garntransportsinne compressed air through the inclined compressed air holes 15, the backward exhaust air flow is reduced. The measure "X" ( FIG. 6 ) indicates that the air bore is preferably set back at least approximately by the size of the diameter d from the narrowest cross section 3. Seen in the transport direction (arrow 16), the texturing 1 and the nozzle core 5 has a Garneinführkonus 6, a cylindrical central portion 7, a cone 8, which simultaneously corresponds to the acceleration channel 11, and an extended texturing 9. The texturing becomes transverse to the flow bounded by a trumpet 12, which may also be designed as an open conical funnel. The FIG. 3 shows a texturing with three compressed air holes 1, which are offset by 120 ° each and lead to the same point Sm in the yarn channel 4.

The FIGS. 4 shows in multiple magnification compared to the actual size of a nozzle core 5 with an impact body 14. The new nozzle core 5 can be designed as a replacement core for the previous of the prior art. In particular, the dimensions B _d , E _L as installation length, L _A + K _H and K _H are therefore preferably not only the same, but also produced with the same tolerances. Furthermore, the trumpet shape in the outer exit region is also preferably produced the same as in the prior art, with a corresponding radius R. The impact body 14 may have any shape: spherical, spherical flat or even in the sense of a dome. The exact position of the baffle 14 in the exit region is maintained by the maintenance of the external mass, corresponding to a same withdrawal gap S _p1 . The texturing 18 remains unchanged to the outside, but is directed backwards and defined by the acceleration channel 11. The texturing space can also be enlarged into the acceleration channel, depending on the height of the selected air pressure. The nozzle core 5 is, as in the prior art made of a high quality material such as ceramic, carbide or special steel and is actually the expensive part of a texturing. Important in the new nozzle is that the cylindrical wall surface 21 as well as the wall surface 22 in the region of the acceleration channel highest Goodness has. The nature of the trumpet extension is determined in terms of yarn friction.

The FIG. 5 shows a whole nozzle head 20 with a nozzle core 5 and a baffle 14, which is anchored via an arm 27 adjustable in a known housing 28. For the threading of the baffle 14 is pulled away with the arm 27 in a known manner according to arrow 29 from the working area 30 of the texturing or swung away. The compressed air is supplied from a housing chamber 31 via the compressed-air bores. The nozzle core 5 is clamped to the housing 33 via a clamping strap 32. Instead of a spherical shape, the impact body may also have a dome shape.

The FIG. 6 shows bottom left purely schematically the texturing of the prior art according to EP 0 088 254 , Two main parameters are highlighted. An opening zone Oe-Z ₁ , and a shock front diameter DAs, starting from a diameter d, corresponding to a nozzle, as in EP 0 088 254 is described. In contrast, the upper right texturing according to EP 0 880 611 shown. It is clearly recognizable that the values Oe-Z ₂ and D _{AE are} larger. The yarn opening zone Oe-Z ₂ begins shortly before the acceleration channel in the region of the compressed air supply P and is already significantly larger with respect to the relatively short yarn opening zone Oe-Z _{1 of} the solution according to EP 0 088 254 ,

The essential statement of the FIG. 6 lies in the diagrammatic comparison of the yarn tension according to the prior art (curve T 311) with Mach <2 and a texturing according to the invention (curve S 315) with Mach> 2 and the new nozzle. In the vertical of the diagram, the yarn tension is in CN. In the horizontal, the production speed Pgeschw. in m / min. shown. The curve T 311 permits the significant collapse of the yarn tension over a production speed of 500 m / min. detect. Above about 650 m / min. broke the texturing with the nozzle accordingly EP 0 088 254 together. In contrast, the curve S 315 with the corresponding nozzle from the EP 0 880 611 in that the yarn tension is not only much higher, but in the range of 400 to 700 m / min. is almost constant and also decreases slowly in the higher production area. The increase in the Mach number is one of the most important parameters for the intensification of the texturing. The enlargement of the blowing angle is one of the most important parameters for the quality of the texturing, as shown with the new nozzle as the third example in the upper left corner. As an example, the injection angle is given in the range of 50 ° to 60 °. The yarn opening zone Oe-Z ₃ is larger than in the solution top right (according to EP 0 880 611 ) and significantly larger than in the solution bottom left (according to EP 0 088 254 ). The other procedural process parameters are the same for all three solutions. In addition to the different injection angle of the range 45 ° to 48 ° and now over 45 ° is the surprisingly positive effect in the first section of the yarn opening zone, such as OZ ₁ and OZ ₂ or as marked in the corresponding circle. As with the FIGS. 7 and 8th is shown, the external difference lies only in the change of the injection angle. The marked increase of the thread tension starts at an angle of more than 48 ° and can only be understood with a combinatorial effect. At least as far as currently the surprisingly positive effect is understood, 48 ° Einblaswinkel means a threshold, but only with texturing according to EP 0 880 611 , This texture nozzle type has a sufficient power reserve, so that even a slight intensification of the yarn opening is converted into an increase in yarn quality.

The FIGS. 7a to 7c and 8a to 8c show diagrammatically the relations of various parameters with respect to the prior art (T341 K ₁ and S345) and the inventive texturing with Einblaswinkeln from 50 ° to 58 °. In the FIG. 8a The thread tension increases sharply from left to right from about 20 CN to 56 cN. The thread tension is more than doubled in the example shown with the new invention on average. The Figure 7a initially shows a slightly less steep increase in yarn tension. So far, all experiments have given variations in the context of the two diagrams 7a and 8a and thus the new knowledge that above 48 ° Einblaswinkel the thread tension is significantly higher. The FIG. 7c as the FIG. 8c each represents three different textured yarn patterns. The upper yarn patterns were made with nozzles of the prior art, according to the top EP 0 088 254 (T-nozzle) and in the middle according to EP 0 880 611 (S-nozzle). The lowermost patterns have been produced with texturing nozzles according to the new invention. In the yarn patterns of the prior art, the relatively large loops are immediately noticeable, with a lack of compact places. The dimensions B ₁ and B ₂ indicate the distance size for the most protruding loops. In the two lower yarn patterns, the dimension B _{3 is} significantly smaller. In particular, however, very compact locations and relatively dense areas with many loops are recognizable at short intervals. The crucial point now, however, is that the yarn patterns behave very differently under load. If the yarn patterns according to the state of the technk (top and middle) are put under tension, the loops are loosened too much and, after removal of the tensile seal, partly remain away. In contrast, the slings remain on the Garnmustern according to the invention even after removal of the tension almost completely. This means that the quality of the texturing could be significantly increased in two respects, which was confirmed in all previously tested Garntitern. Also interesting is the fact that in a thermal exposure according to WO99 / 45182 the corresponding increase in quality and performance could also be confirmed with the new invention. The EP 1 058 745 is declared an integral part of the corresponding additional combination effect.

• der gewünschte Qualitätsstandard und
• das Schlackern, das bei weiterer Erhöhung der Transportgeschwindigkeit zum Zusammenbruch der Texturierung führen kann.

In the episode will now be on the FIG. 9 Reference is made, which shows a schematic overview with respect to the new texturing process. From top to bottom progressively the separate process stages are shown. Flat yarn 100 is fed from above via a first delivery mechanism LW1 at a given transport speed V1 to a texturing nozzle 101 and through the yarn channel 104. Via compressed air ducts 103, which are connected to a compressed air source Pt, highly compressed, preferably not heated, air is blown into the yarn duct 104 at an angle α in the transport direction of the yarn. Immediately thereafter, the yarn channel 104 is conically opened so that in the conical section 102 a strongly accelerated air flow with supersonic, preferably with more than Mach 2, sets. The shock waves generate, as in the aforementioned WO97 / 30200 is described in detail, the actual texturing. The first section from the air infeed point 105 into the yarn channel 104 to the first section of the conical extension 102 serves to loosen and open the plain yarn so that the individual filaments are exposed to supersonic flow. The texturing takes place depending on the level of the available air pressure (9 ... 12 to 14 bar and more) either still within the conical part 102 or in the exit area. There is a direct proportionality between Mach number and texturing. The higher the Mach number the stronger the impact and the more intense the texturing. There are two critical parameters for the production speed:

• the desired quality standard and
• the slack, which can lead to breakdown of the texturing as the transport speed is further increased.

Th. vor.:

thermische Vorbehandlung, evtl. nur mit Garnerhitzung oder mit Heissdampf.

G.mech.:

Garnbehandlung mit der mechanischen Wirkung einer Druckluft- strömung (Überschallströmung).

Th. nach.:

thermische Nachbehandlung mit Heissdampf (evtl. nur Wärme bzw. Heissluft).

D:

Dampf. PL: Druckluft.

It means:

Th. Before:

thermal pretreatment, possibly only with yarn heating or with hot steam.

G.mech .:

Yarn treatment with the mechanical effect of a compressed air flow (supersonic flow).

Th. After .:

thermal aftertreatment with hot steam (possibly only heat or hot air).

D:

Steam. PL: compressed air.

The production speed could with additional thermal treatment up to 1500 m / min. without collapse of the texturing and without slagging, the limit being given by the existing experimental plant. Best texturing qualities could be achieved at production speeds of well over 800 m / min. be achieved. Surprisingly, one or two completely new quality parameters were discovered by the inventors, whereby the regularity mentioned above (higher Mach number = stronger impact = more intense texturing) could only be confirmed in all experiments. The detected parameters are on the one hand in a texturing before and / or downstream heat treatment and on the other hand in an increase in the Mach number by increasing the air pressure and appropriate design of the acceleration channel.

a) Thermal aftertreatment or relaxation

An expert in texturing judges an important quality criterion with reference to the yarn tension of the yarn emerging from the texturing die, which is also recognized as a measure of the intensity of the texturing. The yarn tension adjusts to the textured yarn 106 between the texturing nozzle (TD) and a delivery mechanism LW2. In this area, between texturing nozzle (TD) and delivery LW2, now a thermal treatment was performed on the yarn under tension. The yarn was heated to about 180 ° C. Both with a hotpin or with heated godets as well as with a hotplate (non-contact), initial trials have already been successfully completed, with the surprising result that the quality limit in terms of transport speed could be massively increased. At present, it is believed that the described thermal aftertreatment exerts a fixing effect and at the same time a shrinkage effect on the textured yarn and thereby supports texturing.

b) Thermal pretreatment

To even greater surprise, the thermal pretreatment also has a positive effect on the texturing process. Here, a combinatorial effect between shrinkage and yarn opening in the portion between the air injection point in the yarn duct and the first portion of the conical enlargement in the range of supersonic speed may be the cause of the success. By warming up the yarn, the stiffness is reduced, so that the condition for the loop formation in the texturing process is improved. Again, tests with both hotplates and hotpins as heat sources could be successfully completed. It may also help that the thermal pretreatment of the yarn avoids a negative cooling effect due to the air expansion in the texturing nozzle and therefore texturization can be improved on the heated yarn. At the very high transport speed, part of the heat in the yarn itself is retained even in the area of the loop formation.

The FIG. 9 shows the action of a processing medium, be it by hot air, hot steam or other hot gas on the running yarn shortly or immediately successively performed. The procedural interventions are not isolated in this way, but are combined in an active partnership between two supply plants. This means that the yarn is held only at the beginning and at the end, in between both the mechanical air engagement as well as the thermal engagement takes place. The thermal treatment is carried out on the, even under the mechanical stresses generated by the compressed air in the filaments or in the yarn.

In the FIGS. 10a to 10d Examples of a locally separated mechanical and thermal action are shown. The thermal effect is spatially before or after the actual texturing. In this case, although to a lesser extent, the yarn heating can be used positively for the texturing. The FIGS. 10a to 10d show the use of the so-called heated and driven godets for the thermal treatment with some important applications. The temperature in the galette shows whether it is a heated position. Analogously, in each case a hotplate or a continuous steam chamber according to the invention can be used in each case.

Claims (10)

1. Method for the texturing of continuous yarn by means of a texturing nozzle, with a continuous straight yarn duct, into which compressed air at more than 4 bar is injected at an angle to the yarn transport direction, the yarn duct being designed at the outlet end so as to be widened for a supersonic flow for the generation of loop yarn, characterized in that, in combination, to intensify the yarn opening, the compressed air is injected into the yarn duct at an injection angle of 49° to 80°, and the outlet end of the yarn duct is widened conically at an angle greater than 10° and the blow-air jet is accelerated to more than Mach 2.
2. Method according to Claim 1, characterized in that the injection angle is 50° to 70°.
3. Method according to Claim 1 or 2, characterized in that the yarn duct has a middle, preferably cylindrical portion which merges in the transport direction, without a jump in cross section, into the conical widening, the compressed air being injected, at a distance from the conical widening, into the cylindrical portion in a yarn-opening portion.
4. Method according to one of Claims 1 to 3, characterized in that the yarn is subjected to thermal treatment upstream and/or downstream of the texturing portion.
5. Texturing nozzle for the texturing of continuous yarn and for the generation of a loop yarn, with a continuous straight yarn duct at an inlet end, with a middle, preferably cylindrical portion having an air injection bore arranged at an angle to the centre line of the yarn duct, and with a widened outlet end designed for a supersonic flow, characterized in that, in combination, the air injection bore is arranged at an injection angle of 49° to 80° to the yarn-conveying direction, and the outlet end of the yarn duct is widened conically at an angle greater than 10°.
6. Texturing nozzle according to Claim 5, characterized in that it has only one air injection bore.
7. Texturing nozzle according to Claim 5, characterized in that it has three air injection bores which are offset by 120° and which open at the same injection position.
8. Texturing nozzle according to Claims 5 to 7, characterized in that the air injection position is arranged, at a distance from the conical widening, in the cylindrical portion, the distance corresponding at least approximately to the diameter of the yarn duct.
9. Texturing nozzle according to one of Claims 5 to 8, characterized in that at least the middle, cylindrical portion and the conically widened outlet portion are designed as part of a nozzle core, the nozzle core preferably being designed as an insert into a texturing-nozzle body and being produced from wear-resistant material, in particular ceramic.
10. Texturing nozzle according to Claim 9, characterized in that the nozzle core is designed as an exchangeable core, in such a way that a nozzle core with optimal internal dimensions and inlet angles can be used as a replacement, and, at the outlet end of the conically widened portion, a guide body is preferably arranged which can be advanced at least near to the conically widened outlet portion, the texturing nozzle preferably being designed as part of a texturing head, and the air distribution, particularly preferably to three air injection bores, being arranged in the yarn duct in the texturing head.

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