Entangling nozzle for producing yarns with knots and method of entangling yarn

Abstract

The invention relates to an interlacing jet (100) for producing yarns with nodes, interlaced yarns, DTY or flat yarns with nodes. The interlacing jet (100) comprises a yarn channel (1) with a air spin chamber (2). The air spin chamber (2) comprises an in-flow opening (4) for introducing air into the air spin chamber (2). A channel axis (M) extends in a thread guiding direction (F). The yarn channel (1) comprises a channel width (21) transverse to the channel axis (M). The air spin chamber (2) comprises a chamber length (29) in the thread guiding direction (F) and a chamber extension (28) transverse to said length. The chamber length (29) is at least 180% of the chamber extension (28), preferably at least 200% of the chamber extension (28), and the chamber length (29) is preferably at least 1.5 mm longer than the chamber extension (28).

Description

[0001] The invention relates to a swirling nozzle for the production of knotted yarns, swirled yarn, DTY or smooth yarns with knots, and a method for swirling yarn with the features of the preamble of the independent claims.

[0002] Various nozzle devices are known from the prior art. Nozzle devices are typically used for directing, accelerating, and precisely applying fluids. In this context, "fluids" refers to both gases and liquids. Nozzle devices are used, among other things, in textile machines to join, structure, or treat yarns. The shape of the chamber in which the yarn treatment takes place is crucial for achieving the desired result and determining the required amount of fluid.

[0003] In well-known so-called swirl nozzles, the treatment chamber typically includes an air swirl chamber into which the fluid flow is introduced and swirled. High velocities are required to achieve sufficient swirl. This is achieved by blowing air into the chamber at high pressure.

[0004] Swirl nozzles are used to treat all types of threads, yarns, cables, or similar materials. These can consist of synthetic fibers (plastics such as PE, PP, etc.). They can also consist of natural fibers (cotton, wool, raffia, etc.) or blended fibers. For the purposes of this text, the term "yarn" is used to refer to all these types of materials.

[0005] Swirling nozzles are primarily used to swirl yarns made of synthetic fibers. Swirling offers several advantages, such as improved bobbin structure, unwinding properties, process flow characteristics, and running properties in downstream processing. Filament breaks are prevented, and stray filaments or fuzz can be incorporated. Furthermore, sizing application can be reduced, or weaving without sizing can be made possible. Twisting / twisting can be replaced. Swirling also allows for the joining of different yarns with varying properties or the production of novelty yarns.

[0006] A nozzle device is known from US patent 5,809,761, which comprises a splicing chamber with two lateral chamber sections. In this nozzle, the yarns do not move. It is not suitable for swirling. Further relevant information can be found in documents US patent 4,729,151 A, DE 199 47 894 C1, and DE 10 2006 009139 A1.

[0007] It is an object of the invention to overcome these and other disadvantages of the prior art. In particular, a nozzle device is to be provided which has a high efficiency and ensures reliable yarn treatment. Specifically, the invention should make it possible to achieve a desired knot strength and / or number of knots in a yarn with the lowest possible air pressure and air volume, and correspondingly low energy consumption.

[0008] These tasks are solved by a swirling nozzle for the production of knotted yarns, swirled yarn of DTY or plain yarns with knots and a method for swirling yarn according to the characterizing part of the independent claims.

[0009] The swirl nozzle according to the invention comprises a yarn channel with an air twist chamber. The air twist chamber has an inlet opening for introducing air into the air twist chamber. A channel axis extends in a yarn guiding direction. The yarn channel has a channel width transverse to the channel axis. The air twist chamber has a chamber length in the yarn guiding direction and a chamber extent transverse to this length. The chamber length is at least 180% of the chamber extent, preferably at least 200%, in particular about 220% or 330%, and is preferably at least 1.5 mm longer than the chamber extent. In addition, a chamber wall widens outwards from a channel wall when viewed in the yarn guiding direction, preferably at an angle of no more than 5° with respect to the yarn guiding direction and the channel wall.

[0010] It was surprisingly found that the number and / or quality of nodes can be controlled by the targeted selection of the shape and dimensions of the chamber.

[0011] Typically, as described below, the chamber length, the shape or proportions of the cross-section of an injection opening, the chamber extent or the angle of chamber walls relative to the wall of the yarn channel can be specifically adjusted individually or in combination to achieve a desired number and / or quality of knots.

[0012] For example, a chamber length (relative to the chamber dimensions) of between 210% and 230%, particularly around 220%, leads to the formation of fewer, but more stable, nodes. A length of between 320% and 340%, particularly around 330%, leads to many, but less stable, nodes. The chamber length is preferably at least 1.5 mm longer than the chamber dimensions. A further aspect of the invention therefore relates to a method for adjusting the number and / or quality of nodes, in which the shape and dimensions of the chamber are specifically selected to define the number and / or quality of nodes. In particular, a chamber length is selected relative to the chamber dimensions, whereby a shorter length is chosen to form fewer, but more stable nodes, and a longer length to form more, but less stable, nodes. The lengths are in any case more than 180% of the chamber dimensions and are preferably selected as described above.

[0013] The airflow vectors (direction and intensity of the airflow) within the air twist chamber, in conjunction with the specified flow rate, are crucial for the number and strength of the knots. This flow rate indicates how much more yarn length is fed into the die than exits it. This excess is used for knot formation. Different components of the airflow vectors lead to different effects when processing yarn in twisting dies: Components of the airflow vectors directed in the direction of yarn feed or against it influence yarn feeding and tension. Components of the airflow vectors directed perpendicular to these directions swirl the yarn and are therefore essential for knot formation.The inventors have concluded that, to achieve optimal treatment, the airflow within the air twist chamber should be directed such that it exhibits more transverse components than components in the yarn guidance direction or opposite to the yarn guidance direction. Outside the air twist chamber, however, the airflow vectors should have more components in the yarn guidance direction to ensure sufficient yarn feeding. The airflow vectors can be influenced by the geometry of the air twist chamber, the yarn channel, and the inlet opening.

[0014] To achieve a sufficient number and strength of knots as well as sufficient thread tension and guidance, conventional vortex nozzles required high air pressures and volumes. Through an optimized airflow guidance system based on the invention, the proportions of the airflow vectors in the thread guidance direction and in the transverse direction are optimized so that the air volume and pressure can be reduced without compromising quality, thus saving energy.

[0015] It has been shown that a ratio of at least 1.8 between the chamber length of the air twist chamber and the chamber expansion perpendicular to the chamber length directs the airflow within the air twist chamber over a longer area perpendicular to the yarn guidance direction. This allows for lower air pressures and volumes to be required to ensure sufficient yarn turbulence. Such a turbulence nozzle guides the airflow introduced through the inlet opening in such a way that the amount of fluid introduced can be reduced by up to 20%, while still ensuring that the yarn has the required number and knot strength after treatment.

[0016] In particular, the chamber length can be 180%, 200%, 218%, 228%, or 330% of the chamber dimensions, preferably with a chamber dimension of 1.5 mm, 2 mm, 3 mm, or 3.5 mm. Specific values ​​can be, for example, 1.75 mm, 2.67 mm, 2.94 mm, or 3.08 mm. Preferably, the chamber length is at least 35% of the total die length. The total die length consists of the yarn channel length and the chamber length.

[0017] The chamber expansion here refers to the maximum expansion of the air twist chamber in a transverse direction perpendicular to the thread guidance direction and to an air twist chamber depth.

[0018] The air swirl chamber can comprise two immediately consecutive chamber sections, with the chamber length being composed of the lengths of the chamber sections.

[0019] The air twist chamber can only comprise a chamber area whose chamber walls are rounded. The radius of curvature of the chamber walls can increase in the thread-guiding direction up to the center of the air twist chamber and then decrease again.

[0020] The air twist chamber can also comprise two air twist chamber areas, with the walls being rounded in the thread guidance direction and the curvature of the first area having a larger radius than that of the second area. The walls of the areas preferably transition seamlessly into one another.

[0021] The air twist chamber areas can have a cross-section in a plane along the channel axis of the yarn channel and in the transverse direction, which is essentially teardrop-shaped, so that the chamber areas have rounded and straight sections. The straight sections are arranged converging towards each other in the yarn guidance direction and opposite direction, respectively.

[0022] Preferably, the injection opening is arranged in the swirl nozzle such that the airflow enters the swirl chamber at an angle greater or less than 90° to the channel axis. Preferably, the injection opening is arranged such that the airflow enters the swirl chamber in a region with a smaller dimension than the chamber's dimensions.

[0023] Preferably, the chamber extent is 15–45% of the channel width, more preferably 15% and 35%, and more preferably the chamber extent is a maximum of 5 mm, more preferably a maximum of 3 mm wider than the channel width. For a chamber length of 330% of the chamber extent to form many nodes, the chamber extent is smaller. Typically, it is close to 15% of the channel width. To generate fewer but more stable nodes, a larger chamber extent is chosen, e.g., 35% of the channel width.

[0024] This improves the airflow from the chamber into the yarn channel. The chamber expansion can preferably be between 1.75 mm and 17 mm.

[0025] Preferably the chamber length is a maximum of 350% of the channel width and is in particular a maximum of 30mm, preferably a maximum of 20mm, greater than the channel width.

[0026] Preferably, the air twist chamber has chamber walls which have at least one wall segment rounded in the thread guiding direction, in particular with a radius between 0.3 mm and 6 mm, preferably between 0.5 mm and 2 mm .

[0027] Preferably, the chamber is convexly rounded. Preferably, the chamber walls also include straight wall segments.

[0028] This makes it possible to easily direct the air in a specific direction.

[0029] The chamber wall widens in the thread guidance direction, starting from the canal wall. In particular, the chamber wall can widen at an angle of up to 5° relative to the thread guidance direction and the canal wall.

[0030] Preferably, a first chamber section is arranged first in the thread guidance direction, and a second chamber section immediately follows the first chamber section in the same direction. At the transition from the first to the second chamber section, the chamber has a constriction, such that the chamber dimensions in the first and second chamber sections are larger than the chamber dimensions at the transition.

[0031] This allows the airflow to be separated. By precisely separating the air mass, the amount of air per chamber area can be controlled in addition to the injection angle.

[0032] The air swirl chamber can also comprise more than two chamber sections, each separated by constrictions. The air swirl chamber can include additional structures for directing the airflow, such as surface textures, ribs, edges, constrictions, or widenings. The air swirl chamber can also include coatings for creating air turbulence.

[0033] The first chamber area can have a first chamber depth perpendicular to the chamber length and the chamber extent, and the second chamber area can have a second chamber depth perpendicular to the chamber length and the chamber extent, whereby the chamber depths can be different.

[0034] According to a further aspect of the invention, the swirl nozzle has a yarn channel with an air twist chamber. The air twist chamber has an inlet opening for introducing air into the air twist chamber. A channel axis extends in a yarn guiding direction. According to the invention, the inlet opening has a cross-section with at least one circular section and at least one air guide section, wherein the air guide section is straight or has a radius of curvature that is at least 10 times larger than the radius of curvature of the circular section.

[0035] The cross-sectional geometry of the injection opening has a direct influence on the quality of the turbulence and on the vectors of the flow direction.

[0036] Preferably, the air duct section(s) are not arranged parallel to the channel axis. In a swirl nozzle, the airflows in the transverse direction are decisive for the swirling of the yarn. If the air is directed more in the transverse direction, the yarn is swirled more intensely, resulting in more and stronger knots.

[0037] Preferably, the inlet opening comprises exactly four straight air duct sections in cross-section, which are arranged in a substantially rhombus shape and preferably connected to each other by rounded corners that form the rounded sections. Preferably, a first symmetry line of the rhombus shape is arranged parallel to, and preferably coincidentally with, the duct axis, such that a first corner of the rhombus shape points in the thread guidance direction and a second corner points in the opposite direction to the thread guidance direction, and a third and a fourth corner are arranged in a common plane perpendicular to the first symmetry line.

[0038] The airflow is thus easily directed during the blowing process. The cross-sectional shape can alternatively be triangular or polygonal, with rounded corners. Preferably, the shape comprises an even number of rounded corners, with the cross-sectional shape arranged in the air swirl chamber such that the corners point in both the thread-guiding direction and the opposite direction.

[0039] The cross-sectional shape can also be trapezoidal or kite-shaped.

[0040] It has been shown that the number and stability of nodes can be influenced by the choice of cross-sectional shape. A diamond-shaped injection opening results in fewer but more stable nodes. A kite-shaped injection opening results in more but less stable nodes.

[0041] Preferably, the corners of the diamond shape are rounded. Preferably, the inlet opening comprises a cross-section with an opening length in the thread-guiding direction and an opening width transverse to the opening length. The opening length and the opening width are different, with a ratio between the opening length and the opening width being, in particular, between 1.0 and 1.5. A smaller ratio, typically 1.0, It is used to generate many nodes.

[0042] The rhombus therefore includes angles between its sides that are greater or less than 90°. Preferably, the radii of the obtuse corners differ from those of the acute-angled corners.

[0043] Alternatively, the injection opening can also be at least approximately oval in cross-section.

[0044] The targeted selection of opening width and length allows the air volume to be directed in a specific direction: If the opening length is greater than the opening width, the angle at which the air flows into the chamber at the highest speed changes. The airflow can thus be directed.

[0045] Preferably the opening length is smaller than the opening width, with the first and second corners of the rhombus shape preferably being rounded with a larger radius than the third and fourth corners.

[0046] Alternatively, the opening width can be smaller than the opening length, with the third and fourth corners of the diamond shape preferably being rounded with a larger radius than the first and second corners.

[0047] This targeted choice of opening allows for precise alignment of airflow and air volume, and thus air velocity, depending on the yarns being treated.

[0048] Another aspect of the invention relates to a swirl nozzle with a yarn channel and an air swirl chamber, which has an inlet opening for introducing air into the air swirl chamber. The swirl nozzle is, in particular, a swirl nozzle as described above. A channel axis extends in a yarn guiding direction. The yarn channel has a channel width transverse to the channel axis. The air swirl chamber has a chamber length in the yarn guiding direction and a chamber extent transverse to this length. The air swirl chamber and / or the inlet opening are designed and arranged in the yarn channel such that air introduced through the inlet opening is guided in a vector which, within the air swirl chamber, has more transverse components perpendicular to the channel axis than axial components along the channel axis, and outside the air swirl chamber, has more axial components than transverse components.

[0049] In a swirl nozzle, the airflow directed transversely to the channel axis causes greater turbulence of the yarn and is therefore crucial for knot formation. The axial airflow propels the yarn in the thread direction, resulting in higher yarn tension. Because the airflow in the swirl chamber is directed more transversely than axially, more knots are created in the yarn. If the air is also directed more axially outside the swirl chamber, sufficient yarn tension is maintained to ensure a stable process. If the yarn tension is too low, the yarn flutters so much in front of the nozzle that it can break. Transverse components here always include both radial and tangential components, as the radial components determine the number of knots and the tangential components determine the yarn tension.

[0050] The air twist chamber can be designed such that the air is swirled over an area of ​​at least 40% of the total nozzle length. The total nozzle length includes the length of the yarn channel and the chamber length of the air twist chamber.

[0051] Preferably, the transverse components include more radial components than tangential components.

[0052] The air is thus swirled more, which also twists the yarn more, resulting in stronger and more numerous knots.

[0053] Alternatively, the transverse components have more tangential components than radial components.

[0054] This causes more yarn to be guided out of the nozzle, resulting in greater yarn tension.

[0055] The tasks are further solved by a method for swirling yarn. The yarn is guided along a yarn channel axis of a swirling nozzle. Air is introduced into an air swirl chamber and guided within the chamber in a vector. The vector inside the air swirl chamber comprises more transverse components perpendicular to the channel axis than axial components along the channel axis, and outside the air swirl chamber, it comprises more axial components than transverse components.

[0056] This ensures in a simple way that the yarn achieves a high number of strong knots with low air volume or air pressure.

[0057] The invention is described in more detail in the figures. The figures show: Figure 1: A top view of a first embodiment of a swirl nozzle according to the invention for generating a few stable nodes. Figure 2 : Detail D from the Figure 1 Figure 3 :An inlet opening made of Figure 1Figure 4: A top view of a second embodiment of a swirl nozzle according to the invention. Figures 5a-d: Representations of the airflow velocities at an inlet opening with a circular cross-section and a velocity scale. Figures 6a-d: Representations of the airflow velocities at an inlet opening with a diamond-shaped cross-section and a velocity scale. Figures 7a-d: Representations of the airflow velocities at a swirl nozzle according to the prior art with an air swirl chamber having a chamber length smaller than the chamber dimensions and a velocity scale. Figures 8a-d: Representations of the airflow velocities at a swirl nozzle with an air swirl chamber having a chamber length larger than the chamber dimensions and a velocity scale. Figure 9: A side view of airflow representations of different embodiments of a swirl nozzle. Figure 10: A cross-section.through a swirling nozzle along the yarn guidance direction and Figures 11a and 11b: Examples of swirled yarns Figure 12 A top view of another embodiment of a swirling nozzle according to the invention for generating more but less stable knots Figure 13 An inlet opening made of Figure 12 and Figures 14a and 14b compare the number of knots and knot stability of yarn treated with nozzles according to the invention and with nozzles according to the prior art

[0058] Figure 1Figure 1 shows a top view of a first embodiment of a swirl nozzle 100 according to the invention. The shape, size, and geometry of the nozzle are designed to generate a few but stable knots. The swirl nozzle 100 comprises a nozzle plate 10 with a yarn channel 1 having two channel sections 1a and 1b and an air swirl chamber 2 between sections 1a and 1b. A yarn guide F runs along the central axes Ma and Mb of the channel sections 1a and 1b. The air swirl chamber 2 comprises two chamber regions 2a and 2b. An inlet opening 4 is arranged at the transition between the first chamber region 2a and the second chamber region 2b, through which an airflow is blown into the air swirl chamber 2.

[0059] Along the thread guidance direction F, the first channel section 1a is arranged first, followed by the first chamber area 2a, the second chamber area 2b and then the second channel section 1b.

[0060] An inlet section 3a is located at the inlet of the first channel section 1a, and an outlet section 3b is located at the outlet of the second channel section 1b. Channel section 1a is shorter than channel section 1b. Both channel sections have a dimension 21 of 1.7 mm in the direction of the plane of the drawing. The nozzle plate 10 is essentially mirror-symmetrical with respect to a plane through the central axes Ma and Mb and perpendicular to a plate surface.

[0061] The nozzle plate 10 comprises a base 13. The base 13 has an outline that essentially includes two straight sides 15a and 15b, arranged opposite each other, and two rounded sides 16a and 16b, also arranged opposite each other. The straight sides each have a substantially trapezoidal indentation 14a and 14b, the axes of symmetry of which lie on the central axes Ma and Mb. On the rounded sides, a projection 12a and 12b is arranged for mounting the nozzle on the holder. The projections 12a and 12b have substantially the same radius as the rounded sides 16a and 16b. However, the projections 12a and 12b are shorter than these sides.

[0062] The nozzle plate 10 further comprises two circular openings 11a and 11b passing through the nozzle plate 10.

[0063] The air twist chamber 2 has a chamber length 29 of 4.69 mm in the thread guidance direction F and a chamber dimension 28 of 2.32 mm. The chamber dimension 28 is understood to be the largest dimension of the air twist chamber 2 perpendicular to the chamber length 29 in the plane of the plate. This chamber dimension 28 and this chamber length 29 result in a length-dimension ratio of 2.02.

[0064] The nozzle plate 10 is connected to a cover plate, thus closing the channel sections 1a and 1b and the air twist chamber 2. One or more yarns are inserted into and passed through the air twist chamber 2, while compressed air is applied to the yarn(s) through the inlet opening 4. This creates knots in the yarn(s).

[0065] Since the air swirl chamber 2 is longer relative to its dimensions, the air is guided more in a transverse direction than in shorter chambers, and additionally the air is guided in this transverse direction over a longer area.

[0066] Airflow vector components perpendicular to the thread direction are responsible for turbulence and thus for the number and strength of knots. If the yarn is swirled more and over a longer area, more and stronger knots are formed.

[0067] Figure 2 detail D shows Figure 1The treatment chamber 2 is shown, with its two chamber sections 2a and 2b. Chamber section 2a has a first chamber width 22 perpendicular to the central axis Ma, and the second chamber section 2b has a second chamber width 23 perpendicular to the central axis Mb. A constriction 5 is arranged between chamber sections 2a and 2b. This means that the chamber width 22 of the first chamber section 2a and the chamber width 23 of the second chamber section 2b are greater than the chamber width 51 between chamber sections 2a and 2b. The chamber width 23 of the second chamber section 2b is equal to or greater (preferably about 5%) than the chamber width 22 of the first chamber section 2a. The chamber length here is approximately 200% of the chamber dimensions. The chamber areas 2a and 2b have a teardrop-shaped cross-section in the plane of the plate with sections with a curve and straight sections converging towards each other in the thread guidance direction.

[0068] This constriction 5 causes the airflow to be separated, creating two areas in which the air, and therefore the yarn, is swirled differently.

[0069] The first chamber section 2a has a first section length 24 parallel to the central axes Ma and Mb, which is equal to or greater than the second section length 25 of the second chamber section 2b, which is also parallel to the central axes Ma and Mb. The chamber length 29 of the air swirl chamber 2 consists of the first section length 24 and the second section length 25 and is 5.1 mm.

[0070] The chamber walls of chamber sections 2a and 2b each angle away from the walls of the yarn channel. The chamber walls of the first chamber section 2a have an angle P of approximately 18° to 20° (specifically 19°) to the walls of the yarn channel, while the chamber walls of the second chamber section 2b have an angle S of also 18° to 20°. To create many knots, a smaller angle is used (see also below). Figures 12 and 13 A larger angle is used to generate fewer, but more stable, nodes. The region lengths 24 and 25 are determined by the chamber extent (i.e., the width of the air swirl chamber) and the angle. The widths of the air swirl chambers and / or the angles can be the same or different.

[0071] However, other dimensions and geometries are also conceivable. The geometries described above can also be applied to nozzle lengths of up to 45 mm with channel widths of up to 12 mm. The radii, for example in the yarn channel base, can then be adjusted accordingly.

[0072] Figure 3 shows the injection opening 4 from the exemplary embodiment, from Figure 1 . Chamber areas 2a and 2b of the air swirl chamber 2 (see Figure 1 ) are arranged in immediate succession, with the air swirl chamber 2 (see below). Figure 1 ) at the transition between chamber areas 2a and 2b, there is a constriction 5 in width. The injection opening 4 is located at the transition between chamber areas 2a and 2b. A larger part of the cross-section of the injection opening 4 leads into the first chamber area 2a.

[0073] The inlet opening 4 has a cross-sectional shape that is essentially a parallelogram with rounded corners 41-44. The rounded corners 41-44 are curved sections. The sides of the parallelogram shape are air guide sections 45, which serve to direct the air in a specific direction. The first corner 41 points in the yarn guide direction F, the second corner 42 in the opposite direction to the yarn guide device, so that the line of symmetry 40 of the parallelogram shape is arranged along the central axes Ma and Mb. The first corner 41 and the second corner 42 are both rounded with a radius of 0.2 mm - 2.5 mm. The third corner 43 and the fourth corner 44 both lie in a plane perpendicular to the central axes Ma and Mb and are both rounded with a radius of 0.3 mm - 3 mm. The angle between the straight sections is approximately 50° for the acute angle and approximately 130° for the obtuse angle.The injection opening typically has a width of 1 mm - 10 mm, preferably about 1.32 mm and a length of 0.8 mm - 7 mm, preferably about 0.99 mm, resulting in a width-to-length ratio of approximately 1.33:1.

[0074] If the inlet opening has a parallelogram or rhombus shape, as shown, the air is directed predominantly in a transverse direction to the thread guidance direction, with this transverse direction having components in both tangential and radial directions. Corners 41 and 42, which lie on the line of symmetry in the thread guidance direction, are obtuse, and the other corners 43 and 44 are acute. The angle of the corners influences the orientation of the airflow, so that the angle can be adjusted depending on whether the flow should contain more tangential or radial components.

[0075] Figure 4Figure 1 shows a top view of a second embodiment of a swirl nozzle 100 according to the invention. The swirl nozzle 100 of this embodiment has essentially the same nozzle plate 110 as the nozzle plate of the first embodiment. Therefore, only the differences from the first embodiment will be discussed below.

[0076] The air swirl chamber 102 of this embodiment has two chamber sections, wherein the chamber walls 127a of the first section, arranged in the thread-guiding direction F, have a curvature in the thread-guiding direction with a radius larger than the radius of the curvature in the thread-guiding direction F of the wall sections 127b of the second chamber section. The radius of the curvature of the first wall section 127a can vary. Typically, it is about 25 mm. The radius of the curvature of the second wall section 127b can also vary and is about 15 mm.

[0077] In the embodiment shown here, the chamber length 129 of the air twist chamber 102 is 6.85 mm, and the chamber dimension 128 is 3 mm. The dimension 121 of the yarn channel 101 is 2.4 mm.

[0078] The injection opening 104 essentially has the same cross-sectional shape of a parallelogram as in Fig. 3 shown, with rounded corners.

[0079] The inlet opening 104 is arranged such that the airflow enters the air swirl chamber 102 at an angle of less than 90°.

[0080] Figure 5a Figure 1 shows a nozzle with a circular cross-sectional inlet, as used in swirl nozzles according to the prior art. A simulation was performed to illustrate the influence of the cross-sectional shape on the airflow, with the simulation being shown in Figure 5b - 5d (and also 6b - 6d) was carried out using a swirl nozzle with a yarn channel without an air twist chamber.

[0081] Such an injection opening, known per se, can also be incorporated in an air swirl chamber 2 of a swirl nozzle according to the invention. Figure 1 or 4 be ordered.

[0082] Figure 5b shows a scale of the in the Figures 5c and 5d Flow velocities shown.

[0083] Figure 5c shows the speeds of the airflows in a top view of the nozzle. Figure 5a It can be seen that the airflow with the highest velocity 70 in area 150 mostly flows in the yarn guide direction F or in the opposite direction. Areas 151 with relatively high velocity 71 are mainly located at the yarn channel walls and also flow in the yarn guide direction F or in the opposite direction. However, between the walls of the yarn channel in area 151, there are mainly regions in the middle with relatively low velocity 72 or low velocity 73, which flow in the yarn guide direction F or in the opposite direction.

[0084] Figure 5d Figure 5a shows a side view of the flow velocities of the nozzle. The airflow is primarily directed towards the center of the yarn channel in region 152 of the inlet opening. This means there is a high-velocity area (70°) in the center of the yarn channel near the inlet opening, with transverse components. In region 153, there are also isolated areas of high-velocity flow vectors in the center of the yarn channel, also in the transverse direction. However, these high-velocity areas also predominantly run along the wall opposite the inlet opening in the yarn guidance direction, or vice versa.

[0085] Figure 6a shows an injection opening with a diamond-shaped cross-section without an air swirl chamber, to demonstrate the influence of the nozzle opening geometry on the airflow.

[0086] Figure 6b shows a scale of flow velocities.

[0087] Figure 6c Figure 1 shows a top-view representation of the nozzle flow velocities. This representation shows that an inlet opening with a diamond-shaped cross-section has a larger area 160° with a high flow velocity 70° than in Figure 2. Figure 5c and that the flow deviates more from the thread guidance direction F or its opposite direction. Furthermore, the Figure 6c , that a nozzle with an inlet opening with a diamond-shaped cross-section has more areas 161 with a relatively high flow velocity 71, which is also more frequently guided in the middle between the walls of the yarn channel than in Figure 5c .

[0088] Figure 6d shows a representation of the flow velocities of the nozzle from Figure 6a in side view. Figure 6dThis also shows that a nozzle with a diamond-shaped injection opening has a larger area 163 with a relatively high velocity 71, which is also directed more towards the center between the channel walls than with the nozzle shown in Figure 5d .

[0089] Figure 7a shows a prior art nozzle with a circular injection opening and an air swirl chamber with a chamber length that is smaller than the chamber expansion.

[0090] Figure 7b shows a scale of flow velocities.

[0091] Figure 7c shows a representation of the flow velocities of the nozzle from Figure 7aIn a top view, it can be seen that the flow has a few high-velocity areas (170) where the currents flow perpendicular to the thread direction. There are also areas (171) outside the chamber where the flow has a relatively high velocity (71) and flows primarily in the thread direction or opposite direction.

[0092] Figure 7d shows a representation of the flow velocities of the nozzle from Figure 7a In side view. The flow is mainly directed transversely in area 172 of the inlet opening. In a small area 173 outside the chamber, the flow has a high velocity and flows in the direction of the thread guidance, or vice versa.

[0093] Figure 8a Figure 1 shows a nozzle according to the invention with an air swirl chamber which has a chamber length which is 2.5 times greater than the chamber extension.

[0094] Figure 8bshows a scale of flow velocities.

[0095] Figure 8c shows a representation of the flow velocities of the nozzle from Figure 8a In top view. It can be seen that the flow has large areas in the chamber which have high-velocity flows 71 that lead transversely to the thread guidance direction F and in the middle of the areas 180 in the thread guidance direction high-velocity flows 71 that lead in the thread guidance direction F or opposite direction.

[0096] Figure 8d shows a representation of the flow velocities of the nozzle from Figure 8a In side view. It can be seen that in larger areas 182, 183 the flow is directed more concentrated in the middle between the walls of the yarn channel, i.e. in the transverse direction to the yarn guidance direction F than in Figure 7dThe flows in area 183 near the injection opening have a high velocity 71, and in area 182 a somewhat lower velocity 73. Therefore, there is less airflow in the thread guidance direction F.

[0097] Figure 9 Figure 80 shows a side-view comparison of airflow patterns from different nozzles. Figure 80 shows the airflow from a nozzle without an air swirl chamber, as in [reference missing]. Figure 5a .

[0098] Figure 81 shows the airflow of a nozzle with an air swirl chamber having a chamber length that is smaller than the chamber extent, as in Figure 7a .

[0099] Figure 82 shows the airflow of a nozzle according to the invention with an air swirl chamber having a chamber length which is 1.6 times the chamber extension.

[0100] Figure 83 shows the airflow of a nozzle according to the invention with an air swirl chamber having a chamber length more than twice the chamber dimensions. In Figure 80, the airflow is distributed so that relatively few air currents are concentrated in the center. Lines 84 show that with increasing chamber length, the flow becomes more strongly concentrated in the center.

[0101] Figure 10 The simplified figure shows a cross-section through a nozzle plate 10 in the yarn guidance direction. The yarn channel 1 has the air twist chamber 2 in the middle, into which the injection opening 4 opens at an angle in the yarn guidance direction F.

[0102] The Figures 11a and 11b show, for example, a twisted DTY yarn ( Fig. 11a ) and a swirled smooth yarn ( Fig. 11b ).

[0103] The Figures 12 and 13show a further embodiment of a nozzle according to the invention in a representation analogous to the representation of the first embodiment in the Figures 1 and 2 . The same reference symbols name the same elements as in the Figures 1 and 2 and are not described again. Unlike the embodiment in the Figures 1 and 2 Is the nozzle according to Figures 12 and 13 designed to generate more, but less stable, nodes.

[0104] Channel sections 1a, 1b have an extent 21 in the direction of the drawing plane of 1.7 mm.

[0105] The air twist chamber 2 has a chamber length 29 of 6.74 mm in the thread guidance direction F and a chamber dimension 28 of 2.0 mm. This chamber dimension 28 and this chamber length 29 result in a length-to-dimension ratio of approximately 3.37.

[0106] The chamber walls of chamber sections 2a and 2b each slope away from the walls of the yarn channel at an angle of approximately 6°. This serves to create many knots.

[0107] Figure 13 shows the injection opening 4 from the exemplary embodiment, from Figure 12 . A smaller part of the cross-section of the injection opening 4 leads into the first chamber area 2a.

[0108] The inlet opening 4 has a dragon-shaped cross-sectional shape with rounded corners and a rounded boundary in the chamber area 2a.

[0109] The injection opening 4 has a width B of approximately 1.13 mm and a length L of approximately 1.1 mm, resulting in a width-to-length ratio of approximately 1:1.

[0110] The dragon shape is asymmetrically constructed: its length in chamber area 2a is 0.5 mm and in chamber area 2b it is 0.6 mm.

[0111] With nozzles according to the invention as in Fig. 1Comparative tests were conducted with nozzles as they are known from the state of the art (see e.g. Fig. 14a as are known from WO 2006 / 099763. The operating conditions (especially the air volume at a specific blowing pressure) were adjusted to achieve the same number of knots and knot stability. Figures 14a and 14b show the number of nodes ( Fig. 14a ) and node stability ( Fig. 14b ) of yarns (PES POY dtex 110 / 78f36) each with a nozzle according to the invention (X45.40) and a nozzle according to the standard (P142). To achieve the almost identical number of knots and knot stability, approximately 20% less air was consumed with the nozzle according to the invention.

Claims

1. Interlacing nozzle (100) for the production of knotted yarns, interlaced yarn, of DTY or flat yarns with knots, comprising a yarn channel (1) with an air swirl chamber (2), wherein the air swirl chamber (2) has an injection opening (4) for introducing air into the air swirl chamber (2), a channel axis (Ma, Mb) extends in a yarn guide direction (F), the yarn channel (1) has a channel width (21) transverse to the channel axis (Ma, Mb) and wherein the air swirl chamber (2) has a chamber length (29) in the yarn guide direction (F) and a chamber extension (28) transverse to this length, characterised in that the chamber length (29) is at least 180% of the chamber extension (28), preferably at least 200% of the chamber extension (28) and in particular about 220% or 330%, and preferably the chamber length (29) is at least 1.5 mm longer than the chamber extension (28), wherein a chamber wall, viewed in the yarn guide direction, widens starting from a channel wall, preferably at an angle of at most 5° relative to the yarn guide direction and the channel wall.

2. Interlacing nozzle (100) according to claim 1, wherein the chamber extension (28) is 15%-45% of the channel width (21), preferably 15% or 35%, and wherein preferably the chamber extension (28) is at most 5 mm, more preferably at most 3 mm, wider than the channel width (21).

3. Interlacing nozzle (100) according to claim 1 or 2, wherein the chamber length (29) is at most 350% of the channel width (21) and in particular is at most 30 mm, preferably at most 20 mm, larger than the channel width (21).

4. Interlacing nozzle (100) according to any one of the preceding claims, wherein the air swirl chamber (2) comprises chamber walls, which comprise at least one rounded wall segment, in particular with a radius between 0.3 mm and 6 mm, preferably between 0.5 mm and 2 mm.

5. Interlacing nozzle (100) according to claim 4, wherein the chamber walls comprise straight wall segments.

6. Interlacing nozzle (100) according to any one of the preceding claims, wherein the air swirl chamber (2) comprises a first chamber region (2a) and a second chamber region (2b), wherein the first chamber region (2a) is arranged first in the yarn guide direction (F) and the second chamber region (2b) immediately follows the first chamber region (2a) in the yarn guide direction (F), wherein at the transition from the first chamber region (2a) to the second chamber region (2b) the chamber (2) has a constriction (5), such that the chamber extension (28) in the first and second chamber regions (2a, 2b) is larger than the chamber extension (28) at the transition.

7. Interlacing nozzle (100) for the production of knotted yarns, interlaced yarn, of DTY or flat yarns with knots, in particular an interlacing nozzle (100) according to any one of the preceding claims, comprising a yarn channel (1) with an air swirl chamber (2), wherein the air swirl chamber (2) has an injection opening (4) for introducing air into the air swirl chamber (2), and wherein a channel axis (M) extends in a yarn guide direction (F), characterised in that the injection opening (4) has a cross-section with at least one rounded section and at least one air guide section, wherein the air guide section is straight or has a radius of curvature that is at least 10 times larger than the radius of curvature of the rounded section.

8. Interlacing nozzle (100) according to claim 7, wherein the air guide section is arranged at an angle to the channel axis (M).

9. Interlacing nozzle (100) according to claim 7 or 8, wherein the injection opening in cross-section comprises exactly four air guide sections, which are arranged substantially in a rhombic shape, wherein preferably a first line of symmetry of the rhombic shape is arranged parallel to the channel axis (M), such that a first corner of the rhombic shape points in the yarn guide direction and a second corner points in the opposite direction to the yarn guide direction, and a third and a fourth corner are arranged pointing away in a common plane perpendicular to the first line of symmetry.

10. Interlacing nozzle (100) according to claim 9, wherein the corners of the rhombic shape are rounded.

11. Interlacing nozzle (100) according to any one of the preceding claims, wherein the injection opening (4) comprises a cross-section with an opening length in the yarn guide direction (F) and an opening width transverse to the opening length, wherein the opening length and the opening width are different, wherein in particular a ratio between the opening length and the opening width is between 1.0 and 1.5.

12. Interlacing nozzle (100) according to claim 9 or 10 and 11, wherein the opening length is smaller than the opening width, wherein preferably the first and the second corner of the rhombic shape are rounded with a larger radius than the third and fourth corner.

13. Interlacing nozzle (100) according to claim 9 or 10 and 11, wherein the opening width is smaller than the opening length, wherein preferably the third and the fourth corner of the rhombic shape are rounded with a larger radius than the first and second corner.

14. Interlacing nozzle (100) for the production of knotted yarns, interlaced yarn, of DTY or flat yarns with knots, in particular an interlacing nozzle (100) according to any one of the preceding claims, comprising a yarn channel (1) with an air swirl chamber (2), wherein the air swirl chamber (2) has an injection opening (4) for introducing air into the air swirl chamber (2), a channel axis (M) extends in a yarn guide direction (F) and the yarn channel (1) has a channel width (21) transverse to the channel axis (M), the air swirl chamber (2) has a chamber length (29) in the yarn guide direction (F) and a chamber extension (28) transverse to this length, characterised in that the air swirl chamber (2) and / or the injection opening (4) is / are designed and arranged in the yarn channel (1) such that air introduced through the injection opening (4) is guided in a vector which, within the air swirl chamber (2), has more transverse components transverse to the channel axis (M) than axial components along the channel axis (M) and, outside the air swirl chamber (2), comprises more axial components than transverse components.

15. Interlacing nozzle (100) according to claim 14, wherein the transverse components have more radial components than tangential components.

16. Interlacing nozzle (100) according to claim 14, wherein the transverse components have more tangential components than radial ones.

17. Method for interlacing yarn, wherein the yarn is guided along a channel axis (M) of a yarn channel (1) of an interlacing nozzle (100) and the introduced air is guided in a vector within an air swirl chamber (2), characterised in that the vector, within the air swirl chamber, comprises more transverse components transverse to the channel axis (M) than axial components along the channel axis (M) and, outside the air swirl chamber (2), comprises more axial components than transverse components.

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