EP0880611A1

EP0880611A1 - Method of aerodynamical texturing, texturing nozzle, nozzle head and use thereof

Info

Publication number: EP0880611A1
Application number: EP97901514A
Authority: EP
Inventors: Gotthilf Bertsch; Erwin Schwarz
Original assignee: Heberlein Fasertechnologie AG
Current assignee: Heberlein AG
Priority date: 1996-02-15
Filing date: 1997-02-12
Publication date: 1998-12-02
Anticipated expiration: 2017-02-12
Also published as: CN1211293A; RU2142029C1; WO1997030200A1; GB2310219B; JPH09310241A; TR199801567T2; ES2160923T3; DE19605675A1; DE19605675C2; JP3433946B2; TW477838B; DE19605675C5; GB2310219A; GB9702679D0; KR100296216B1; CN1095887C; JP2000514509A; DE59704244D1; KR19990082499A; US6088892A

Abstract

To increase the intensity of the texturing, the invention proposes to maintain airflow above Mach 2 by using a nozzle duct of a certain form. The total opening angle of the nozzle duct directly upstream of the texturing zones is larger than the ideal Laval angle and has an effective length which is preferably a multiple of the narrowest diameter of the nozzle. The invention improves, in particular, texturing quality, especially at high production speeds which can be increased up to in the range of 600 to 1000m/min and beyond. It has been demonstrated, surprisingly, that the new nozzle core can be designed in such a manner that it has all the advantages of the invention and can be used as a replacement part for prior art nozzle cores. The same applies to the complete texturing head since the invention can be used with the same external geometric overall dimensions, at the same air pressure and with the same air quantity.

Description

Process for aerodynamic texturing, texturing nozzle, nozzle head and use

Technical field

The invention relates to a method for aerodynamic texturing of yarn with a texturing nozzle with a continuous yarn channel, at one end of which the yarn is fed and at the other end of which is discharged as textured yarn, compressed air having a feed pressure of more than four bar in at a central section fed the yarn channel and the blowing air jet is accelerated to supersonic in an expanding acceleration channel. The invention further relates to a texturing nozzle, a nozzle head and its use, with a continuous yarn duct having a compressed air supply, on one side of which yarn can be fed and on the other side of which the texturing can be carried out.

State of the art

Two types of texturing nozzles have largely become established in air-jet texturing technology. These can be differentiated according to the type of compressed air supply to the yarn channel. One is the air-jet texturing nozzle based on the radial principle. The compressed air is supplied via one or more, mainly radially arranged air channels, e.g. according to EP-PS No. 88 254. Texturing nozzles according to the radial principle have their field of application above all in yarns which require rather low deliveries of less than 100%. In special cases, with so-called fancy yarns, up to 200% overdelivery can be permitted for a short time. The second type has the axial principle. The compressed air is fed into an expanded chamber of the yarn channel via axially directed channels. Such a solution is shown in EP-PS No. 441 925. Texturing nozzles based on the axial principle are used successfully, especially with very high levels of up to 300%, sometimes even up to 500%. The two corresponding practical solutions also differ particularly in the design of the nozzle opening in the area of the nozzle outlet. The solution according to EP-PS No. 441 925 has a nozzle opening corresponding to a Laval nozzle before the outlet end. The Laval nozzle is characterized by a very small opening angle of around 8 ° to a maximum of 10 °. The opening angle is the same or smaller than the so-called ideal Laval angle, the air speed in the nozzle opening can be increased smoothly above the sound limit, provided that the air pressure at the narrowest point of the Laval nozzle is above a critical pressure ratio. Laval had already recognized that when the air pressure was lowered, even in an ideal nozzle, the limit zone of the speed increase shifted into the nozzle. An impact front with the known compression surges can form. In most fields of malfunction engineering, compression shocks are avoided if possible. The texturing process is more complex in that not only does a supersonic flow with a gas be required, but at the same time the yarn is passed through the middle of the nozzle and processed through the butting front. To compensate for all flow losses, air pressure texturing uses air pressures of more than 4 bar, usually more than 6 bar. The theoretical maximum speed of air (at a temperature of 20 ° C, an infinite inlet pressure and an ideal Laval angle of less than 10 °) is around 770 m / sec. In reality, the maximum possible air speed at 12 bar is between 500 and 550 m / sec, ie under Mach 2. For this, reference is made to a scientific study in "Chemical fibers / textile industry May 1981". According to the most widespread specialist opinion, the texturing process as such is attributed to the effect of the compression surges, which are a phenomenon of the supersonic flow. The textured yarn with a texturing nozzle, with an ideal Laval angle, was long regarded as a quality benchmark. Due to this given quality, other nozzle shapes could be searched for. According to EP-PS No. 88 254, the applicant actually succeeded in developing an alternative nozzle shape with a trumpet-shaped nozzle mouth, the so-called Hemajet nozzle. Only at first glance does the trumpet shape appear to be outside the Laval laws. A second investigation (International Textii-Bulletin yarn production 3/83) showed that a supersonic flow is also generated with the trumpet shape, with maximum air velocities in the range of about 400 m / sec. were measured. The practice of yarn finishing has also shown that the shape of the trumpet is more advantageous in special applications. The Hemajet nozzle is based on a convex outlet opening that can be written with a simple radius. If you check the extension immediately afterwards at the narrowest point, it turns out that this is initially a very short distance in the range of the ideal lava opening angle. This is a major reason why both types of nozzles sometimes produce similar texturing results. Both have established themselves as standard nozzles in various applications.

Although texturing nozzles based on the radial principle are superior to texturing nozzles based on the axial principle, particularly in the case of deep deliveries, the article mentioned shows that the thread tension in the radial principle drops sharply with increasing delivery. It is one Experience shows that yarn tension immediately after the texturing nozzle is a quality feature for texturing A good quality comparison (higher / lower values) is made easier if at least 50 m / min better 100 m / mm differences in production speeds are compared Under quality all possible yarn quality can be It is also understood to include production conditions that cannot be measured directly as quality scopes on the textured product, but which experience has to take into account. Z For example, strong or slight slagging of the incoming threads is a factor or a value that does not exceed a certain value Fui is more permissible for the direct measurement comparison according to the teaching according to the invention, preferably the tensile force on the yarn after texturing (in cN or mean cN) and the percentage deviation of the instantaneous tensile force (sigma%) are selected. The two values can be chosen separately t or recorded as a total value (AT value) For this purpose, reference is made to the ATQ measurement and evaluation principle of the registrations in cooperation with the company Retech AG, Switzerland. Yarn speeds below 400 m / min do not present any difficulties today At yarn speeds of 400 to 600 m / min, a qualitatively accepted texturing is obtained. On the other hand, if the yarn take-off speed is increased further to over 600 m / min, a qualitative deterioration is found. This is manifested, for example, in such a way that individual loops of textured yarn are used for no explainable reason Stand out more strongly from the textured yarn The known texturing nozzles, especially with compact yarns, when the highest quality is required for texturing, can only be used at production speeds below 400 m / mm. The production speed is understood to mean the speed at which the yarn is removed from the texturing nozzle. In texturing, therefore, in relation to the production speed, in addition to the quantity limit, there is an absolute texturer limit at which the texturing breaks down, for example due to excessive slagging

Presentation of the invention

The object of the invention was now either to increase the quality of the text at a given speed or to increase the production speeds, for example in the range from 400 to 900 m / min and more, and to achieve the same good or at least approximately the same good at higher production speeds Achieving Qualltat, like at lower production or yarn speeds. Another aspect of the task was to be able to convert existing plants with the least effort, be it in terms of Qualltat and / or performance The method according to the invention is characterized in that the yarn tension, in particular as constant yarn tension as possible, is increased by accelerating the blown air jet in the acceleration channel to Mach 2 or more, in order to optimize the ratio of yarn tension to yarn speed.

The invention further relates to a texturing nozzle with a continuous yarn channel with an outlet-side acceleration channel and a compressed air supply (P) into the yarn channel, on one side of which yarn can be fed and on the other side of which textured yarn can be drawn off, and is characterized in that the acceleration-effective section of the Acceleration canals have a length (f ₂ ) of more than 1.5 times the diameter (d), at the beginning of the acceleration canal and a total opening angle (α ₂ ) larger than the ideal Laval angle.

It was recognized that the first key to quality was yarn tension after the texturing nozzle. The quality can only be improved if the thread tension is increased. The real breakthrough was only made possible when the flow of the blown air jet was increased over the Mach 2 area. Contrary to the obvious prejudice in the whole professional world, this was achieved structurally by the design of the acceleration channel according to the invention. Surprisingly, it was possible to confirm with many test series that not only the quality is improved, but that, according to the invention, this is adversely affected to an astonishingly small extent by an increase in the production speed. The inventor recognized that the task can only be solved by intensifying the texturing process. However, the task was only solved with the discovery that the Mach number is a central influencing factor. So far, experts have been too fixated on the flow velocity. However, the speed cannot be increased in the given textile practice over the areas mentioned above (below Mach 2). In the prior art, one was guided either by the regularities of the Laval nozzles or by purely empirically determined nozzle shapes that were found to be good. Even a slight increase in the Mach number above 2 already gave significant results. The best explanation for the corresponding intensification of the texturing process is seen in the fact that the speed difference is increased immediately before and after the impact front, which has a direct effect on the corresponding attack forces of the air on the filaments. The increased forces in the area of the butt front cause an increase in the yarn tension. By increasing the Mach number, the action on the front is immediately increased. Accordingly, the yarn tension could be increased significantly with the new invention, and the quality could be ensured to an extent not previously possible. According to the invention, the law was recognized: higher Mach number = stronger impact = more intensive texturing. The intensified supersonic flow covers the opened yarn on a wider front and much more intensely. This ensures that no loops can move sideways across the effective zone of the butt front. Since the generation of the supersonic flow in the acceleration channel is based on the expansion, one gets through a higher Mach range, e.g. instead of Mach 1, Mach 5, 2.5 also an increase or almost a doubling of the effective outlet cross-section. Various surprising observations could already be made with the first series of experiments:

- When using a supersonic duct designed for the higher Mach range, a qualitative improvement in the texturing occurred in each case at the same production speed, in comparison to the prior art;

- With the texturing nozzles of the prior art, there is always a strong, gradual loss of quality when the production speed is increased. With the new texturing nozzles there is also a loss of quality, but this only occurred to a small extent in all tests and, depending on the yarn titer, only at very high production speeds of e.g. over 800 m / min. on;

- Test trials with individual yarn titers were carried out up to a production speed of VOOO up to 1500 m / min. performed without breakdown of texturing.

- In terms of measurement technology, it immediately became apparent that the yarn tension could be increased by around 50% on average. The increased value also remained over a large speed range of e.g. 400 to 700 m / min. almost constant.

- It has certainly also shown that the choice of the supply pressure of the compressed air also has a significant influence. To ensure the higher Mach numbers, a higher feed pressure is required in many cases. This is approximately between 6 and 14 bar, but can be increased to 20 and more bar.

The comparative tests, the state of texturing technology and the new invention resulted in the following regularity over a remarkably wide range: the texturing quality at a higher production speed is at least equal or better at a higher production speed compared to the texturing quality at a lower production speed with a supersonic duct designed for the lower Mach range. The texturing process is at air speeds in the shock front of Mach 2, e.g. with Mach 2.5 to Mach 5 so intense that almost all of the loops are adequately captured even at the highest yarn throughput speeds and are well integrated into the yarn. The generation of an air speed in the high Mach range within the acceleration channel does two things. First, the individual filaments are opened more and pulled into the nozzle with greater force. The texturing no longer breaks down at the highest speeds. Second, the whole Filament composite evenly and directly into the shock front zone within clear outer channel boundaries.

The new invention also allows a number of particularly advantageous configurations both for the method and for the device. Reference is also made to claims 2 to 10 and 12 to 1 7 in the acceleration channel The path is drawn in and opened, and handed over to the subsequent Textuπerzonc. An essential point in Textuπertechnik is that the end processor can maintain the quality that was once found to be good for further production. The constancy of the same ordeal is often the top priority. This is achieved particularly well with the new solution, because the factors determining the texturing are easier to control than in the prior art.The main point for this is the mastery of the yarn tension, especially with regard to the constancy of the yarn tension and the constancy of the texturing quality Compressed air in the acceleration duct is accelerated over a length of at least 1.5, preferably at least 2 times the narrowest diameter, the ratio of the outlet cross section to the inlet cross section of the acceleration duct being greater than 2. The total opening angle of the blown air jet should be greater than 10 °, i.e. larger than the ideal Laval angle. So far, the best results have been achieved when the blown air jet has been accelerated steadily. However, different variants with different accelerations were also examined. The results were in some cases almost as good as the constant acceleration with a continuously conical acceleration channel. The blown air jet is then guided to the acceleration channel without a deflection, through a discontinuous and strongly widening section. One or more yarn threads with the same or different delivery can be introduced and with a production speed of 400 to over 1200 m / min. be textunert. The compressed air jet in the supersonic duct is accelerated to 2.0 to 6 Mach, preferably to 2.5 to 4 Mach. The best results were achieved if the exit-side end of the yarn duct was delimited by a baffle, such that the textured yarn was approximately at right angles to that Yarn channel axis is discharged through a gap.

Furthermore, the blowing air is particularly preferably fed from the supply point into a cylindrical section of the yarn channel directly in an axial direction at an approximately constant speed up to the acceleration channel, the compressed air being introduced into the yarn channel via one or more, preferably three or more bores or channels , such that the compressed air is blown in at an angle (ß) with the component in the direction of the acceleration duct. Surprisingly, with very good results, air-jet texturing nozzles are modified according to the radial principle in accordance with the new invention, that is to say texturing nozzles according to EP-PS No. 88 254, which is explained as part of this application for their technical designs. The compressed air is preferably introduced into the yarn channel via three bores, such that the compressed air is blown in at a corresponding angle with the conveying component in the direction of the supersonic channel. As in the prior art, the new solution can also be used to texturize one or more yarn threads with a wide variety of traditions. The entire theoretically effective expansion angle of the supersonic channel should be from the smallest to the largest diameter above 10 °, but below 40 °, preferably within 12 ° to 30 °, particularly preferably 12 ° to 25 °. According to the current roughness values, an upper limit angle (total angle) of 35 ° to 36 ° has resulted, above which the supersonic flow always breaks off. In a conical acceleration duct, the compressed air is accelerated essentially continuously. The nozzle channel section immediately in front of the supersonic channel is preferably approximately cylindrical, with the delivery component being blown into the cylindrical section in the direction of the acceleration channel. The pulling force on the yarn is increased with the length of the acceleration channel. The expansion of the nozzle or the increase in the Mach number results in the intensity of the texturing. The acceleration channel should have at least a cross-sectional expansion 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 greater than the diameter of the yarn channel at the beginning of the acceleration channel. The acceleration channel can be completely or partially continuously expanded, have conical sections and / or have a slightly spherical shape. However, the acceleration channel can also be formed in stages and have different acceleration zones, with at least one zone with high acceleration and at least one zone with low acceleration of the compressed air jet. The exit area of the acceleration channel can also be cylindrical or approximately cylindrical and the entry area can be greatly expanded, but expanded less than 36 °. If the boundary conditions for the acceleration channel have been complied with according to the invention, the aforementioned variations of the acceleration channel have proven to be almost equivalent or at least equivalent. The yarn channel adjoins the supersonic channel with a strongly convex, preferably trumpet-shaped, more than 40 ° widened yarn channel mouth, the transition from the supersonic channel into the yarn channel mouth preferably being discontinuous. A decisive factor was found in the fact that the impact conditions in the texturing space can also be positively influenced and kept stable with an impact body. A preferred embodiment of the texturing nozzle according to the invention is characterized in that it has a continuous yarn channel with a central cylindrical one Section into which the air supply opens, as well as in the thread running direction a preferably conical acceleration channel directly adjoining the cylindrical section with an opening angle (α ₂ ) greater than 10 °, and a subsequent extension section with an opening angle (ö) greater than 40 °, the Extension section is conical or trumpet-shaped.

The invention further relates to a nozzle head with a texturing nozzle with a yarn channel, which has an inlet section in the yarn conveying direction, a cylindrical central section with the compressed air supply, and an expanded air acceleration section and a preferably deliverable impact body on the outlet side, and is characterized in that the air acceleration section has a length ( i ₂ ) of more than the diameter (d) at the beginning of the acceleration section, and has a total opening angle (α ₂ ) greater than 10 °. The yarn channel is preferably formed with the central section and the air acceleration section in a nozzle core that can be installed and removed.

The invention was also based on the object of improving the quality and / or the production speed in an existing system. The solution according to the invention is characterized by the use of a nozzle core, as a replacement for an existing nozzle core (or an entire nozzle head with a nozzle core) for increasing the production speed and / or for improving the texturing quality. The nozzle core or the entire nozzle head have identical fitting dimensions as the nozzle cores or the nozzle heads of the prior art. The new replacement nozzle core has an air acceleration section with a length (i ₂ ) of more than 1.5 times the diameter (d) at the beginning of the acceleration channel (1 1) and a total opening angle (α ₂ ) greater than 10 °.

The tests carried out to date have also shown that wetting the yarn before texturing brings better results even with the new invention. However, it was not yet possible to finally clarify the influence of the condensation surge known in the specialist world.

Brief description of the invention

The invention will now be explained in more detail by means of some examples. Show it:

Figure 1 shows the mouth of a nozzle of the prior art; FIG. 2 shows an example of a design of the acceleration channel according to the invention; 3 shows a nozzle core according to the invention according to FIG. 2, ie FIG. 4 shows a texturing nozzle or a nozzle head with a built-in nozzle core in use with a quatthat measurement, FIG. 4a shows a measurement course of the AT value during a short measuring time, and FIG. 5 shows a nozzle core of the prior art according to EP-PS No. 88 254, FIG. 6 shows a nozzle core according to the invention with the same external installation dimensions, FIG. 7 shows some advantageous configurations for the acceleration channel according to the invention, FIG. 8 shows a texturing nozzle or nozzle head, partly in section, and FIG. 8a shows a part of the enlargement 8 in the outlet area of the texturing nozzle, FIG. 9 shows a comparison of textured yarn according to the state of the art / new invention with regard to yarn tension, FIG. 10 shows quality measurements in comparison with the prior art and various nozzles according to the invention in tabular form, and FIG textured yarn, state of the art (right chts), FIG. 1 1a yarn processed according to the invention (left), FIG. 12, measuring arrangement for comparative measurements, prior art / new invention, FIGS. 13, 13a and 14 individual force elongation as a comparison of prior art (FIGS. 1, 3, 13a) as well as new invention Figure 14,

Ways and implementation of the invention

In the following, reference is now made to FIG. 1, which represents only the area of the nozzle mouth of a known texturing nozzle, in accordance with EP-PS No. 88 254. The corresponding texturing nozzle 1 has a first cylindrical section 2, which at the same time also has the narrowest cross section 3 with a diameter d corresponds to the narrowest cross-section 3, the yarn channel 4 begins to expand in the shape of a trumpet, whereby the shape can be defined with a radius R. Due to the resulting supersonic flow, a corresponding front face diameter DAs can be determined. The front face diameter DAs can be determined relatively determine exactly the tearing point or tearing point A, which is slightly larger than the clear diameter of the nozzle. If a tangent is now created on both sides in the area of the tapping point A, a Hull cone with an opening angle α of approximately 22 ° results that with the nozzle shape mentioned with a corresponding surface The impact front detaches at an opening angle of 22 °. For the special features of the impact front, reference is made to the scientific studies mentioned at the beginning. The acceleration range of the air can also be determined by the length l _λ from the point of the narrowest cross section 3, as well as the demolition point A ±. Since it is a real supersonic flow, the air speed can be roughly calculated from this. VDa is the highest air speed. Vd is the speed of sound at the narrowest point 3. In the present example, the following values were calculated:

If at Vd an air speed of 330 m / sec. is present (Mach 1), then Mach 1, 8 (M _Da ) results at exit A from the supersonic area. These values are close to the measured values according to the Textii bulletin. The actual acceleration distance within the supersonic channel is very short and, as was recognized on the basis of the new invention, too short.

FIG. 2 now shows an example of an embodiment of the acceleration duct 11 according to the invention, which corresponds to the length l ₂ . The texturing nozzle 10 according to the invention corresponds in the example shown up to the narrowest cross section 3 to the nozzle core according to FIG. 1, but is then different. The opening angle α ₂ is specified at 20 °. The discharge point A ₂ is located at the end of the supersonic duct, where the yarn duct merges into a discontinuous, strongly conical or trumpet-shaped extension 12 with an opening angle d> 40 °. Due to the geometry there is a

Butt front diameter DAE, which is much larger compared to Figure 1. The following relationships result in FIG. 2:

L2 / d = 4.2; Vd <= 330 m / sec. (Mach 1); - αj- ~ 2.5 -> M _DE = Mach 3.2

According to the new invention, an extension of the acceleration channel 1 1 with a corresponding opening angle increases the impact front diameter DAE. Various studies have shown that the previous assumption, for example according to textile practice, that the texturing is a result of multiple knock-out penetrations of the yarn is at least partially incorrect. Immediately in the area of the formation of the shock front, the largest possible compression shock front 13 is created, followed by an abrupt pressure increase zone 14. The actual texturing takes place in the area of the compression shock front 1 3. The air moves about 50 times faster than the yarn. Many tests have shown that the detachment point A ₃ , A _{4 can} also migrate into the acceleration duct 11, namely when the feed pressure is reduced. In practice, it is now a matter of determining the optimum feed pressure for each yarn, the length ( ₂ ) of the acceleration channel being designed for the worst case, that is to say it is chosen to be somewhat too long. In contrast, an increase of the feed pressure in the solution of the prior art very little, since the separation point is almost unaffected by the pressure.

In the following, reference is now made to FIG. 3, which shows a preferred embodiment of an entire nozzle core 5 in cross section. The outer fitting shape is preferably adapted exactly to the nozzle cores of the prior art. This applies above all to the critical installation dimensions, the bore diameter BD, the total length L, the nozzle head height KH, and the distance LA for the compressed air connection P. Tests have shown that the previous optimal injection angle ß can be maintained, as can the position of the corresponding compressed air holes 15. The Garπkanal 4 has in the inlet area of the yarn, arrow 16, a yarn insertion cone 6. Due to the compressed air directed in the yarn transport direction (arrow 16) via the oblique compressed air bores 15, the exhaust air flow directed backwards is reduced. The dimension “X” (FIG. 6) indicates that the air hole is preferably set back from the narrowest cross section 3 at least approximately by the size of the diameter. Seen in the direction of transport (arrow 1 6), the texturing nozzle 10, or the nozzle core 5, has a yarn insertion cone 6, a cylindrical middle section 7, a cone 8, which at the same time corresponds to the acceleration channel 11, and an expanded texturing space 9. The texturing space is delimited transversely to the flow by a trumpet shape 12, which can also be designed as an open conical funnel.

FIG. 4 shows an entire texturing head or nozzle head 20, with a built-in nozzle core 5 '. The unprocessed yarn 21 is fed to the texturing nozzle via a feed mechanism 22 and transported further as textured yarn 21 '. A baffle 23 is located in the outlet region 13 of the texturing nozzle. A compressed air connection 24 is arranged on the side of the nozzle head 20. The textured yarn 21 'runs at a transport speed VT over a second delivery unit 25. The textured yarn 21' is guided 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%) is measured. The measurement signals are fed to a computer unit 27. The corresponding quality measurement is a prerequisite for optimal production monitoring. Above all, the values are also a measure of the yarn quality. In the air blast texturing process, the quality determination is difficult because there is no defined loop size. It is much easier to determine the deviation from the quality that the customer has found good. This is possible with the ATQ system because the yarn structure and its deviation can be determined, evaluated and displayed by means of a thread tension sensor 26 and the AT value can be displayed by a single characteristic number. A thread tension sensor 26 detects, in particular, the analog electrical signal Thread tension after the texturing nozzle The AT value is continuously calculated from the mean value and variance of the thread 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. During production, the thread tension or changes the variance (uniformity) of the thread tension, also changes the AT value. Where the upper and lower limit values are, can be determined with thread mirrors, knitting or fabric samples. They vary depending on the quality requirements. The very special advantage of the ATQ measurement is that that different types of malfunctions from the process are recorded at the same time Z e.g. identical texturing, thread wetting, filament breakage, nozzle contamination, impact ball spacing, hot pin temperature, air pressure differences, POY plug-in zone, yarn guide, etc. Figure 4a is a display pattern for the course of the AT value a short measurement time

Figures 5 and 6 show in multiple enlargement compared to the real large nozzle cores; 5 shows a nozzle core of the prior art, FIG. 6 shows a nozzle core according to the invention. Since the new invention succeeded in solving the problem inside the nozzle core, the new nozzle core could be designed as an exchange core for the previous one. In particular the dimensions B _d , E ₍ as installation length, L _A + K _H and K _H are therefore preferably not only provided in the same way, but also with the same tolerances. In addition, the shape of the trumpet in the outer outlet area is preferably produced in the same way as in the prior art, with a corresponding radius R The impact body can have any shape, spherical, spherical flat or even in the sense of a spherical cap (FIG. 8a). The exact position of the impact body in the exit area is retained by maintaining its outer mass, corresponding to an equal extraction gap S _p1 is denoted by 1 7 in Figure 5, remains unchanged on the outside, but is back The texturing space can also be enlarged into the acceleration channel depending on the level of the selected air pressure, as indicated by two arrows 18 in FIG. 6. The nozzle core is made of a high-quality material such as in the prior art Ceramic, hard metal or special steel is made and is actually the expensive part of a textuuse. It is important with the new nozzle that the cylindrical wall surface 21 as well as the wall surface 22 has the highest quality in the area of the acceleration channel. The nature of the trumpet extension is considered with regard to the Yarn friction set

7 shows differently designed supersonic channels. In some cases only the opening angle for a section of the supersonic channel is given. Contrary to all expectations, the test results / variations were not very large than The best forms resulted in purely conical acceleration channels with an opening angle of more than 12 ° between 15 ° and 25 ° (far left in the picture). The vertical column a shows pure cone shapes, in rows b and c a combination of cone shape and short cylindrical sections, whereas the Row d has a parabolic acceleration channel. Row c shows a combination of cone and trumpet shapes. In rows f and g, the first section of the acceleration channel is greatly expanded and then goes into a cylindrical part. Tests with all types have produced remarkably good results. so far the best results have been determined with rows a and d for da <^; Understanding, it is not unimportant that the central cylindrical section has a diameter in the range of millimeters or even less than 1 mm. The length of the acceleration section is in the range of approximately 1 cm or less

FIG. 8 shows an entire nozzle head 20, with a nozzle core 5 and a baffle 14, which is anchored in a known housing 24 in an adjustable manner via an arm 23. For threading, the baffle 14 with the arm 23 is removed in a known manner according to arrow 25 from the Working area 13 of the texturing nozzle is pulled away or pivoted away. The compressed air is supplied from a housing chamber 27 via the compressed air bores. The nozzle core 5 is firmly clamped to the housing 24 via a clamping plate 28. Instead of a spherical shape 30, the impact body can also have a spherical shape 31

FIG. 8a shows the combination of a texturing nozzle according to the invention with some variations in the shape of the impact body 14. The impact ball 14 easily penetrates into the trumpet-shaped opening of the nozzle. With a dashed line, a normal working position is shown in FIG. 6, dash-dotted lines, the impact ball touching the trumpet shape 12 Dash-dotted position can be used as a starting position for the exact position in the working position. The 1 trumpet shape 12 on the one hand and the impact body 14 on the other hand result in an internal texturing space 18 and a free gap Sp _! is for the outgoing textured air and for the removal of the textured yarn The gap Sp _! is determined empirically on Gi and the yarn quatate, optimized and defined for the production. The texturing space 18 is given an influenceable shape and size depending on the ball diameter and shape of the impact body. The inventor found that with the size of the withdrawal gap pnmar the pressure ratio for the Acceleration channel can be adjusted. By reducing the discharge gap Sp, the flow resistance and the static pressure in the texturing room change. For the pressure division, gap width changes in the large valve order of tenths of a millimeter change Solution But can also on asymmetrical and deviating from the circular cross-sections, with respect to the supersonic channel, for example. be formed with a rectangular cross section or with an approximate rectangle or approximately oval shapes. It is also possible to design a nozzle so that it can be opened for threading. For this purpose, reference is made to the international application PCT / CH96 / 0031 1, which is explained for the technical content as an integral part of the present application.

FIG. 9 shows the texturing of the prior art in a purely schematic manner at the bottom left. Two main parameters are highlighted. An opening zone Oe-Zi and a butt front diameter DAs, starting from a diameter d, corresponding to a nozzle as shown in FIG. 1. In contrast, the new texturing is shown in the top right. It is very clear that the values Oe-Z2 and DAE are significantly larger. Another interesting aspect was also identified. The yarn opening starts before ^¬ the acceleration duct in the region of the supply of compressed air P, that is already in the cylindrical portion, which is denoted by VO as pre-opening. The dimension Vo greater than d is preferably selected.

The essential statement in FIG. 9 lies in the diagrammatic comparison of the yarn tension according to the prior art (curve T 31 1) with Mach <2 and a texturing nozzle according to the invention (curve S 31 5) with Mach> 2. The yarn tension is in the vertical of the diagram in CN. The production speed Pspeed is in the horizontal. shown in m / min. Curve 31 1 allows the yarn tension to collapse significantly over a production speed of 500 m / min. detect. Above about 650 m / min. the texturing broke down. In contrast, curve S 31 5 with the nozzle according to the invention shows that the yarn tension is not only much higher, but in the range from 400 to 700 m / min. is almost constant and only drops slowly in higher production areas. Increasing the Mach number is one of the most important "secrets" for progress with the new invention.

FIG. 10 shows a printout of an ATQ quality test. The top table shows the mean tensile stress (cN), the middle the percentage deviation of the instantaneous tensile force (Sigma%) and the bottom table the corresponding AT values. The values of a standard T nozzle, that is to say a texturing nozzle of the prior art, are indicated in each case on the first horizontal line of each table. The values of S-nozzles according to the invention with different opening angles from 19 ° to 30.6 ° are then from top to bottom. All nozzles according to the invention had the same length of the supersonic duct. The values 0.00 indicate that either texturing was not possible or the test was not carried out. Figures 1 1 and 1 1 a show a visual comparison using textured yarn. Figure 1 1 (right half of the picture) shows a texturing with a nozzle of the prior art, at 400, 600 and 800 m / min. Production speed. At 800 m / min. the pressure was increased to 1 2. The result can be up to 400 m / min. as well and at 600 m / min. can be described as conditionally good. The results of 5 tests with a nozzle according to the invention are correspondingly shown on the left half of the figure (FIG. 1 a). It can be seen that even at 800 m / min. Production speed is still a conditionally good result. In contrast to this, the comparative example (right next to it) would be rejected by the customer according to the prior art, even though a feed pressure of 1 2 bar was used.

In Figure 1 1 and 1 1 a identical yarn quality and the same conditions were tested. Core: PA dtex 78f66x 1; Effect: PA dtex 78f66x1; OF 12/30%. FIG. 12 shows the test arrangement for the comparative tests according to FIG. 11. The following measured values were determined (setting data and measurement data): (see table state of the art / new invention)

The analogous statements relating to FIGS. 11 and 12 can also be found in FIGS. 13, 13a and 14. On the left in the picture is a graphical representation of a large number of threads, each with the individual force F cN / dtex (vertical) over the elongation E in% (horizontal). Figure 13 belongs to Table 1 2a, Figure 13a to 12b and Figure 14 to Table 12c. The graphical representation is a single force / strain curve.

With a relatively small measure, in particular due to the inventive design of the area of the acceleration channel, the new invention has produced many surprising effects. This allows, for example:

- Instead of installing a nozzle core of the prior art without any changes in the other process parameters according to the invention, with the result that the quality becomes more stable and better;

- or the customer would like to increase the production speed slightly. - The installation of a new nozzle core allows an increase in production speed without loss of quality;

- or the customer wants to greatly increase the production speed. - The quality can also be ensured here by increasing the supply pressure of the air;

- In any case, either only the nozzle core or the entire nozzle head can be replaced. PRIOR ART New invention

T-nozzle T-nozzle S-nozzle

Texturing 1 2a 1 2b 1 2c

Nozzle core T 31 1 K 31 1 K S 31.5 Z pressure pe bar 9 9 9, thread wetting l / h 2 2 2 PK distance mm 3.8 3.8 3.8

W 1 .1 OF c% 12 1 2 12, m / min. 560 7JB.4 784.

W 1 .2 OFef% 30 30 30 m / min. 650 910 910

VV 2 pilot m / min (100%) 500 700 7QQL

W4 m / min 500 700 700% of W3 0 SET temp ° C

F 2 cN n. Nozzle 4.2 2.9 - .5.9

F 3 cN Stab.Zone

F 4 cN before SET

F 5 cN before WW

ATQ AT value 23 46. 27

Carnprüfung

Titer theo. dtex

Titer eff. dtex 1 70 1 70 1 70.

Elongation at break% 26.2 23.5 32.7

Tear resistance cN / dtex 2.99 2.84 3.4.9

Tear strength absolutely gr 507 483 593

The best texturing nozzle to date has a continuous yarn channel with an outlet-side acceleration channel and a compressed air supply (P) into the yarn channel, at one end of which yarn can be fed and at the other end of which textured yarn can be drawn off, and is characterized in that it has a continuous yarn channel a central, cylindrical section, into which the air supply opens, and in Fadenlaufπchtung a preferably directly adjoining the cylindrical section conical supply channel with an opening angle (α ₂ ) greater than 10 ° and a subsequent extension section with an opening angle greater than 40 °, the extension section being conical or trumpet-shaped

The texturing nozzle can be designed as a nozzle core, which can be installed and removed in a nozzle head, and in the installed state forms a nozzle head, or can be designed as a nozzle head with an installed nozzle core, with a baffle arranged on the outlet side, which can be set on the nozzle core, and the fexible space can be limited is

Claims

1. Method for aerodynamic texturing of yarn with a texturing nozzle with a continuous yarn channel, at one end of which the yarn is fed and at the other end of which is discharged as textured yarn, compressed air in a central section having a feed pressure of more than four bar Yarn channel fed and the blowing air jet is accelerated to supersonic in an expanding acceleration channel, so that the yarn tension is increased by accelerating the blowing air jet in the acceleration channel to a speed more than Mach 2, in order to optimize the ratio of yarn tension to yarn speed

2. The method according to claim 1, characterized in that for a given feed pressure of the diuck air between 6 and 14 bar or more, the yarn tension emer given yarn quatrate at a production speed of 400 to 600 m / min. is about constant

3. The method according to claim 1 or 2, characterized in that the compressed air in the acceleration channel is accelerated over a length of at least 1.5, preferably more than 2 times the narrowest diameter, the ratio of the outlet cross section to the inlet cross section of the corresponding channel section being greater than 2.

4. The method according to any one of claims 1 to 3, characterized in that the total opening angle of the blown air jet is greater than 10 ° or greater than the ideal Laval angle, preferably 12 ° to 30 °, particularly preferably 15 ° to 25 °.

5. The method according to claim 1 to 4, characterized in that the acceleration of the blowing air takes place continuously or increasingly or discontinuously or with different accelerations and / or with sections with zero acceleration.

6. The method according to claim 1 to 5, characterized in that the blowing air is fed directly from the supply point into the gain channel in an axial direction at an approximately constant speed up to the acceleration channel, the compressed air being supplied via one or more, preferably three Bores are introduced into the yarn channel in such a way that the compressed air is blown in at an angle (.beta.) With the delivery component in the direction of the acceleration channel

7. The method according to any one of claims 1 to 6, characterized in that the blown air jet is subsequently guided to the misting channel without being deflected by a greatly widening section

8. The method according to any one of claims 1 to 7, characterized in that one or more yarn with the same or different tradition is introduced, and with a production speed of 400 to 1500 m / min. or more preferably 500 to 1200 m / min. be textured.

9. The method according to any one of claims 1 to 8, characterized in that the compressed air jet in the supersonic channel is accelerated to Mach 2.0 to 6 Mach, preferably to Mach 2.5 to 4.

10. The method according to any one of claims 1 to 9, characterized in that the austπttsseittge end of the yarn channel is delimited by a baffle, such that the textured yarn is discharged through a gap approximately at right angles to the yarn channel axis

11 Texturing nozzle with a continuous yarn channel with an outlet-side acceleration channel and a compressed air supply (P) into the yarn channel, on one side of which yarn can be fed and on the other side of which textured yarn can be drawn off, so that the acceleration-effective section of the acceleration channel 11 is long ( ₂ ) of more than T / 2 times the diameter (d) at the beginning of the acceleration channel (11) and has a total opening angle (α ₂ ) greater than 10 °

12 texturing nozzle according to claim 11, characterized in that the effective widening angle (α _? ) Of the acceleration channel is greater than 10 °, but less than 40 °, preferably 12 ° to 30 °, particularly preferably 15 ° to 25 °

13 texturing nozzle according to claim 11 or 12, characterized in that the acceleration channel has at least a cross-sectional expansion area of 1 2.0 or greater and a total opening angle (α ₂ ) greater than 10 °

14 texturing nozzle according to one of claims 11 to 13, characterized gekennzeic hnet that the acceleration channel is conical and preferably merges into a much more expanded trumpet-shaped opening

15 texturing nozzle according to one of claims 11 to 14, characterized in that the length ( ₂ ) of the acceleration channel is at least twice, preferably 3 to 15 times, particularly preferably 4 to 12 times larger than the diameter (d) of the yarn channel at the beginning of Acceleration channel

16 texturing nozzle according to one of claims 11 to 15, characterized in that the entry area of the acceleration channel is cylindrical or approximately cylindrical (VOj and the exit area is greatly expanded, but is expanded more than 40 °

17 texturing nozzle according to one of claims 11 to 16, characterized in that the air-blowing nozzle has a compressed air supply (P) according to the radial principle

18. Nozzle head with a texturing nozzle with a yarn channel, which in the yarn conveying direction has an inlet section, a cylindrical middle section with the compressed air supply, and an expanded air acceleration section and on the outlet side a preferably deliverable impact body, characterized in that the air acceleration section has a length ( ₂ ) of has more than the diameter (d) at the beginning of the acceleration section, and a total opening angle (cu) greater than 10 °.

19. Nozzle head according to claim 18 with a texturing nozzle with a yarn channel, which has an inlet section in the yarn conveying direction, a cylindrical middle section with the compressed air supply and an expanded air acceleration section and on the outlet side a preferably deliverable impact body, characterized in that the yarn channel with the middle section and the air acceleration section is formed in an insertable and removable nozzle core.

20. Use of a texturing nozzle designed as a nozzle core, according to one of claims 1 to 18, as a replacement for an existing nozzle core or an entire nozzle head for increasing the production speed and / or for improving the texturing quality, the nozzle core or the entire nozzle head being identical Like the nozzle cores or nozzle heads of the prior art, the fitting dimensions have an air acceleration section with a length {i ₂ ) of more than the diameter (d) at the beginning of the acceleration section, and a total opening angle (α ₂ ) greater than 10 ° having.

21. Nozzle core in particular according to one of claims 1, 11 or 20, characterized in that it has a continuous yarn channel with a central cylindrical section into which the air supply opens and a conical widening section which adjoins the cylindrical section in the thread running direction and has an opening angle larger than 10 ° and a subsequent conical or trumpet-shaped extension section.