INTERLACING NOZZLE FOR THE PRODUCTION OF YARNS WITH KNOTS AND METHOD FOR INTERLACING YARNS

Abstract

The invention relates to an interlacing nozzle (100) for the production of knotted yarns, interlaced yarn, of DTY or plain yarns with knots. The interlacing nozzle (100) comprises a yarn channel (1) with an air twist chamber (2). The air twist chamber (2) includes an injection port (4) for introducing air into the air twist chamber (2). A channel axis (M) extends in a yarn guiding direction (F). The yarn channel (1) comprises a channel width (21) transverse to the channel axis (M). The air twist chamber (2) comprises a chamber length (29) in the yarn guiding direction (F) and a chamber extension (28) transverse to this length. The chamber length (29) is at least 180% of the chamber extension (28), preferably at least 200% of the chamber extension (28), and preferably the chamber length (29) is at least 1.5 mm longer than the chamber extension (28).

Claims

1-17. (canceled)

18. An interlacing nozzle for the production of knotted yarns, interlaced yarn, DTY or plain yarns with knots, comprising a yarn channel with an air twist chamber, wherein the air twist chamber has an injection 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 and the air twist chamber has a chamber length in the yarn guiding direction and a chamber extension transverse to the chamber length, the chamber extension having a chamber extension length, and wherein the chamber length is at least 180% of the chamber extension length.

19. The interlacing nozzle according to claim 18, wherein the chamber extension length is 15%-45% of the channel width.

20. The interlacing nozzle according to claim 18, wherein the chamber length is at most 350% of the channel width.

21. The interlacing nozzle according to claim 18, wherein the air twist chamber comprises chamber walls which comprise at least one rounded wall segment.

22. The interlacing nozzle according to claim 21, wherein the chamber walls comprise straight wall segments.

23. The interlacing nozzle according to claim 18, wherein the chamber wall expands from a channel wall as viewed in the yarn guiding direction at an angle of no more than 5° with respect to the yarn guiding direction and the channel wall.

24. The interlacing nozzle according to claim 18, wherein the air twist chamber comprises a first chamber region and a second chamber region, wherein the first chamber region is arranged first in yarn guiding direction and the second chamber region immediately follows the first chamber region in yarn guiding direction, wherein at the transition from the first chamber region to the second chamber region the chamber has a constriction so that the chamber expansion in the first and second chamber regions is greater than the chamber expansion at the transition.

25. An interlacing nozzle for the production of knotted yarns, interlaced yarn, of DTY or plain yarns with knots comprising a yarn channel with an air twist chamber, wherein the air twist chamber has an injection opening for introducing air into the air twist chamber and wherein a channel axis extends in a yarn guiding direction, wherein the injection opening has a cross-section with at least one round section and at least one air guiding section, wherein the air guiding section is straight or has a radius of curvature which is at least 10 times larger than the radius of curvature of the round section.

26. The interlacing nozzle according to claim 25, wherein the air guide section is arranged at an angle to the channel axis.

27. The interlacing nozzle according to claim 25, wherein the injection opening comprises exactly four air guiding sections in cross-section, which are arranged in a substantially diamond shape, so that a first corner of the diamond shape points in yarn guiding direction and a second corner points in the opposite direction to the yarn guiding direction, and a third and a fourth corner are arranged pointing away in a common plane perpendicular to the first line of symmetry.

28. The interlacing nozzle according to claim 27, wherein the corners of the diamond shape are rounded.

29. The interlacing nozzle according to claim 25, wherein the injection opening comprises a cross-section with an opening length in yarn guiding direction and an opening width transverse to the opening length, wherein the opening length and the opening width are different.

30. The interlacing nozzle according to claim 27, wherein the opening length is smaller than the opening width.

31. The interlacing nozzle according to claim 27, wherein the opening width is smaller than the opening length.

32. An interlacing nozzle for the production of knotted yarns, interlaced yarn, of DTY or plain yarns with knots comprising a yarn channel with an air twist chamber, wherein the air twist chamber has an injection opening for the introduction of air into the air twist chamber, a channel axis extends in a yarn guiding direction and 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 extension transverse to said length, wherein the air twist chamber and/or the injection opening is designed and arranged in the yarn channel in such a way that air introduced through the injection opening is guided in a vector which, inside the air twist chamber, has more transverse components transverse to the channel axis than axial components along the channel axis and, outside the air twist chamber, has more axial components than transverse components.

33. The interlacing nozzle according to claim 32, wherein the transverse components comprise more radial components than tangential components.

34. The interlacing nozzle of claim 32, wherein the transverse components comprise more tangential components than radial components.

35. A method for interlacing yarn, wherein the yarn is guided along a channel axis of a yarn channel of an interlacing nozzle and the introduced air is guided inside an air twist chamber in a vector, wherein the vector inside the air twist chamber comprises more transverse components transverse to the channel axis than axial components along the channel axis and outside the air twist chamber comprises more axial components than transverse components.

36. The interlacing nozzle according to claim 18, wherein the chamber length is at least 1.5 mm longer than the chamber extension length.

37. The interlacing nozzle according to claim 18, wherein the chamber extension length is at most 5 mm wider than the channel width.

38. The interlacing nozzle according to claim 21, wherein the rounded wall segment has a radius between 0.3 mm and 6 mm.

39. The interlacing nozzle according to claim 25, wherein the interlacing nozzle comprises a yarn channel with an air twist chamber, wherein the air twist chamber has an injection 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 and the air twist chamber has a chamber length in the yarn guiding direction and a chamber extension transverse to the chamber length, the chamber extension having a chamber extension length, and wherein the chamber length is at least 180% of the chamber extension length.

40. The interlacing nozzle according to claim 32, wherein the interlacing nozzle comprises a yarn channel with an air twist chamber, wherein the air twist chamber has an injection 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 and the air twist chamber has a chamber length in the yarn guiding direction and a chamber extension transverse to the chamber length, the chamber extension having a chamber extension length, and wherein the chamber length is at least 180% of the chamber extension length.

Description

[0060] The invention is described in more detail in the figures. The figures show:

[0061] FIG. 1: A top view of a first embodiment of an interlacing nozzle according to the invention for producing a few stable knots.

[0062] FIG. 2: Detail D from FIG. 1

[0063] FIG. 3: An injection opening from FIG. 1

[0064] FIG. 4: A top view of a second embodiment of an interlacing nozzle according to the invention

[0065] FIG. 5a-d: Representations of the velocities of the air flow in an injection opening with a circular cross-section and scale of the velocities

[0066] FIG. 6a-d: Representations of the velocities of the air flow in an injection opening with a diamond shape cross-section and scale of velocities

[0067] FIG. 7a-d: Representations of the velocities of the air flow in a prior art interlacing nozzle with an air twist chamber with smaller chamber length than chamber extension and scale of velocities.

[0068] FIG. 8a-d: Representations of the velocities of the air flow in an interlacing nozzle with an air twist chamber with a larger chamber length than chamber extension and scale of the velocities.

[0069] FIG. 9: A side-by-side illustration of air flow velocities of various interlacing nozzle designs

[0070] FIG. 10: A cross-section of an interlacing nozzle along the yarn feed direction, and

[0071] FIGS. 11a and 11b: examples of interlaced yarns

[0072] FIG. 12A top view of a further embodiment of an interlacing nozzle according to the invention for producing more but less stable knots

[0073] FIG. 13: An injection opening as shown in FIG. 12 and

[0074] FIGS. 14a and 14b a comparison of the number of knots and knot stability of yarn treated with nozzles according to the invention and with nozzles according to the state of the art.

[0075] FIG. 1 shows a top view of a first embodiment of an interlacing nozzle 100 according to the invention. The shape, size and geometry of the nozzle is designed to produce few but stable knots. The interlacing nozzle 100 comprises a nozzle plate 10 having a yarn channel 1 with two channel sections 1a and 1b and an air twist chamber 2 between the sections 1a and 1b. A yarn guiding direction F runs along central axes Ma and Mb of the channel sections 1a and 1b. The air twist chamber 2 comprises two chamber regions 2a and 2b. At the transition between the first chamber region 2a and the second chamber region 2b, an injection opening 4 is arranged through which an air flow is injected into the air twist chamber 2.

[0076] Along the yarn guiding direction F, the first channel section 1a is arranged first, followed by the first chamber region 2a, the second chamber region 2b and then the second channel section 1b.

[0077] An inlet section 3a is arranged at the inlet of the first channel section 1a and an outlet section 3b is arranged at the outlet of the second channel section 1b. The channel section 1a is shorter than the channel section 1b. Both channel sections have an extension 21 in the direction of the drawing plane of 1.7 mm. The nozzle plate 10 has a substantially mirror symmetrical configuration with respect to a plane through the center axes Ma and Mb and perpendicular to a plate surface.

[0078] The nozzle plate 10 includes a base surface 13, the base surface 13 having an outline comprising substantially 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 each of the rounded sides, a protrusion 12a and 12b is arranged for mounting the nozzle on the holder. The protrusions 12a and 12b have substantially the same radius as the rounded sides 16a and 16b. However, the protrusions 12a and 12b are shorter than these sides.

[0079] The nozzle plate 10 further includes two circular openings 11a and 11b extending through the nozzle plate 10.

[0080] The air twist chamber 2 has a chamber length 29 of 4.69 mm in the yarn guiding direction F and a chamber extension 28 of 2.32 mm. The chamber extension 28 is to be understood as the largest extension of the air twist chamber 2 transverse to the chamber length 29 in the plate plane. This chamber expansion 28 and this chamber length 29 result in a length to expansion ratio of 2.02.

[0081] The nozzle plate 10 is connected to a cover plate so that the channel sections 1a and 1b and the air twist chamber 2 are closed. One or more yarns are introduced into and passed through the air twist chamber 2 while compressed air is applied to the yarn or yarns through the injection opening 4. As a result, knots are created in the yarn or yarns

[0082] Since the air twist chamber 2 is longer relative to the expansion, on the one hand the air is guided more in a transverse direction than in shorter chambers, and in addition the air is guided over a longer area in this transverse direction.

[0083] Air flow vector components transverse to the yarn guiding direction are responsible for the interlacing and thus for the knot number and strength. If the yarn is now interlaced more and over a longer area, more and tighter knots are formed.

[0084] FIG. 2 shows detail D from FIG. 1, showing treatment chamber 2 with two chamber regions 2a and 2b. The chamber region 2a has a first chamber width 22 transverse to the center axis Ma and the second chamber region 2b has a second chamber width 23 transverse to the center axis Mb. A constriction 5 is arranged between the chamber regions 2a and 2b. That is, the chamber width 22 of the first chamber region 2a and the chamber width 23 of the second chamber region 2b are greater than the chamber width 51 between the chamber regions 2a and 2b. The chamber width 23 of the second chamber region 2b is equal to or greater (preferably about 5%) than the chamber width 22 of the first chamber region 2a. The chamber length here is about 200% of the chamber extent. The chamber regions 2a and 2b have a teardrop-shaped cross-section in the plate plane with sections with a rounding and straight sections converging in yarn guiding direction.

[0085] This constriction 5 causes the air flow to be separated, creating two areas in which the air and thus the yarn are swirled differently.

[0086] The first chamber region 2a has a first region length 24 parallel to the central axes Ma and Mb, which is equal to or greater than the second region length 25 of the second chamber region 2b parallel to the central axes Ma and Mb. The chamber length 29 of the air twist chamber 2 consists of the first region length 24 and the second region length 25 and is 5.1 mm.

[0087] The chamber walls of the chamber regions 2a and 2b each lead away from the walls of the yarn channel at an angle. The chamber walls of the first chamber region 2a have an angle P of about 18° to 20° (specifically 19°) with respect to the walls of the yarn channel, and the chamber walls of the second chamber region 2b have an angle S of also 18° to 20°. A smaller angle (see also FIGS. 12 and 13 below) is used to produce many knots, and a larger angle is used to produce fewer but more stable knots. The area lengths 24 and 25 are determined by the chamber expansion (i.e., the width of the air twist chamber) and the angle. The widths of the air twist chambers and/or the angles can be the same or different.

[0088] However, other dimensions and geometries are also conceivable. The geometries described above can also be used for nozzle lengths of up to 45 mm with channel widths of up to 12 mm. The radii, e.g. in the yarn channel base, can then be adapted accordingly.

[0089] FIG. 3 shows the injection opening 4 from the embodiment example, from FIG. 1. The chamber regions 2a and 2b of the air twist chamber 2 (cf. FIG. 1) are arranged directly one after the other, whereby the air twist chamber 2 (cf. FIG. 1) has a constriction 5 in the width at the transition between the chamber regions 2a and 2b. The injection opening 4 is arranged at the transition between the chamber regions 2a and 2b. A larger part of the cross-section of the injection opening 4 leads into the first chamber region 2a.

[0090] The injection opening 4 has a cross-sectional shape which is essentially a parallelogram with rounded corners 41-44. The rounded corners 41-44 are rounding sections. The sides of the parallelogram shape are air guiding sections 45, which serve to guide air in a particular direction. The first corner 41 points in yarn guiding direction F, and the second corner 42 points in the opposite direction to the yarn guiding device, so that the symmetry line 40 of the parallelogram shape is arranged along the center 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 are both 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 about 50° for the acute angle and about 130° for the obtuse angle. The injection opening has a width of typically 1 mm-10 mm, preferably about 1.32 mm, and a length of 0.8 mm-7 mm, preferably about 0.99 mm, and thus a width to length ratio of about 1.33:1.

[0091] If the injection opening has a parallelogram or diamond shape, as shown, the air is guided increasingly in a transverse direction to the yarn guiding direction, the transverse direction having components in both tangential and radial directions. The corners 41 and 42, which lie on the line of symmetry in the yarn guiding direction, are obtuse and the other corners 43 and 44 are acute. The angle of the corners has an influence on the orientation of the air flow, so that depending on whether the flow is to comprise more tangential or radial components, the angle can be adjusted.

[0092] FIG. 4 shows a top view of a second embodiment of an interlacing nozzle 100 according to the invention. The interlacing nozzle 100 of this embodiment has substantially 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.

[0093] The air twist chamber 102 of this embodiment has two chamber regions, wherein the chamber walls 127a of the first chamber region arranged in the yarn guiding direction F has a rounding in the yarn guiding direction with a radius which is larger than the radius of the rounding in the yarn guiding direction F of the wall portions 127b of the second chamber region. The radius of the rounding of the first wall portion 127a may vary. Typically, it is about 25 mm. The radius of the roundness of the second wall section 127b may also vary and be about 15 mm.

[0094] In the embodiment example shown here, the chamber length 129 of the air twist chamber 102 is 6.85 mm, and the chamber extension 128 is 3 mm. The extension 121 of the yarn channel 101 is 2.4 mm.

[0095] The injection opening 104 comprises substantially the same cross-sectional shape of a parallelogram as shown in FIG. 3, with rounded corners.

[0096] The injection opening 104 is arranged so that the air flow enters the air twist chamber 102 at an angle of less than 90°.

[0097] FIG. 5a shows a nozzle with an injection opening having a circular cross-section, as used in prior art interlacing nozzles. To illustrate the influence of the cross-sectional shape on the air flow, a simulation was carried out. The simulation in FIGS. 5b-5d (and also 6b-6d) was based on an interlacing nozzle with a yarn channel without an air twist chamber.

[0098] Such an injection opening, known per se, can also be arranged in an air twist chamber 2 of an interlacing nozzle according to the invention as shown in FIG. 1 or 4.

[0099] FIG. 5b shows a scale of the flow velocities shown in FIGS. 5c and 5d.

[0100] FIG. 5c shows the velocities of the air flows in the top view of the nozzle of FIG. 5a. It can be seen that the flow of air with the highest velocity 70 in area 150 mostly flows in the yarn guiding direction F or opposite direction. Areas 151 with relatively high velocity 71 are mainly located at the yarn channel walls and also lead in yarn guiding direction F or opposite direction. Between the yarn channel walls in region 151, however, there are regions in the center mainly with relatively low velocity 72 or low velocity 73, which lead in yarn guiding direction F or opposite direction.

[0101] FIG. 5d shows a side view of the flow velocities of the nozzle of 5a. The air flow is mainly directed to the center of the yarn channel in the region 152 of the injection opening, that is, there is a region 152 with high velocity 70 in the center of the yarn channel in the region of the injection opening with transverse components. In region 153, there are occasional areas of flow vectors with high velocity also in the transverse direction in the center of the yarn channel. However, the areas with high velocity here also increasingly lead along the wall opposite the entry opening in yarn guiding direction or in the opposite direction.

[0102] FIG. 6a shows an injection opening with diamond shape cross-section without air twist chamber to show the influence of the geometry of the nozzle opening on the air flow.

[0103] FIG. 6b shows a scale of the flow velocities.

[0104] FIG. 6c shows a representation of the flow velocities of the nozzle in plan view. This illustration shows that an injection opening with a diamond shape cross-section has a larger area 160 with a high flow velocity 70 than in FIG. 5c and that the flow deviates more from the yarn guiding direction F or its opposite direction. In addition, FIG. 6c shows that a nozzle with an injection opening with a diamond shape cross-section has more areas 161 with a relatively high flow velocity 71, and this is also guided more in the center between the walls of the yarn channel than in FIG. 5c.

[0105] FIG. 6d shows a side view of the flow velocities of the nozzle of FIG. 6a. FIG. 6d also shows that a nozzle with a diamond shape injection opening has a larger area 163 with a relatively high velocity 71, which is also directed more to the center between the channel walls than in the nozzle shown in FIG. 5d.

[0106] FIG. 7a shows a prior art nozzle with a circular injection opening and an air twist chamber with a chamber length smaller than the chamber dimension.

[0107] FIG. 7b shows a scale of flow velocities.

[0108] FIG. 7c shows a top view of the flow velocities of the nozzle from FIG. 7a. It can be seen that the flow has a few areas 170 with high velocity where the flows are in the transverse direction to the yarn guiding direction. There are areas 171 outside the chamber where the flow has a relatively high velocity 71 and is primarily in the yarn guiding direction or opposite direction.

[0109] FIG. 7d shows a side view of the flow velocities of the nozzle of FIG. 7a. Here, the flow is mainly guided in the transverse direction in the area 172 of the injection opening. In a small area 173 outside the chamber, the flow has a high velocity and leads in yarn guiding direction, resp. opposite direction.

[0110] FIG. 8a shows a nozzle according to the invention with an air twist chamber having a chamber length which is 2.5 times larger than the chamber extension.

[0111] FIG. 8b shows a scale of the flow velocities.

[0112] FIG. 8c shows a top view of the flow velocities of the nozzle of FIG. 8a. It can be seen that the flow has large areas in the chamber which have flows with high velocity 71 leading in transverse direction to the yarn guiding direction F and in the middle of the areas 180 in yarn guiding direction flows with high velocity 71 leading in yarn guiding direction F resp. opposite direction.

[0113] FIG. 8d shows a side view of the flow velocities of the nozzle from FIG. 8a. It can be seen that in larger areas 182, 183 the flow is more concentrated in the center between the walls of the yarn channel, i.e. in transverse direction to the yarn guiding direction F than shown in FIG. 7d. The flows in area 183 near the injection opening have a high velocity 71, and in area 182 a somewhat lower velocity 73. There is therefore less air flow in yarn guiding direction F.

[0114] FIG. 9 shows a side-by-side representation of air flows from various nozzles.

[0115] Illustration 80 shows the air flow of a nozzle without an air twist chamber, as in FIG. 5a.

[0116] FIG. 81 shows the air flow of a nozzle with an air twist chamber having a chamber length smaller than the chamber dimension, as in FIG. 7a.

[0117] The illustration 82 shows the air flow of a nozzle according to the invention with an air twist chamber with a chamber length which is 1.6 times as large as the chamber extension.

[0118] FIG. 83 shows the air flow of a nozzle according to the invention with an air twist chamber with a chamber length which is more than twice as large as the chamber extension. In FIG. 80, the airflow is distributed so that relatively few airflows are concentrated in the center. Lines 84 show that increasing the length of the chamber results in an increased orientation of the flow toward the center.

[0119] FIG. 10 shows in simplified form a cross-section through a nozzle plate 10 in yarn guiding direction. The yarn channel 1 has the air twist chamber 2 in the center, into which the injection opening 4 opens at an angle in the yarn guiding direction F.

[0120] FIGS. 11a and 11b show an example of an interlaced DTY yarn (FIG. 11a) and an interlaced plain yarn (FIG. 11b).

[0121] FIGS. 12 and 13 show a further embodiment of a nozzle according to the invention in a representation analogous to the representation of the first embodiment in FIGS. 1 and 2. Identical reference signs designate identical elements as in FIGS. 1 and 2 and are not described again. In contrast to the embodiment in FIGS. 1 and 2, the nozzle according to FIGS. 12 and 13 is designed to generate more and therefore less stable nodes.

[0122] The channel sections 1a, 1b have an extension 21 in the direction of the drawing plane of 1.7 mm.

[0123] The air twist chamber 2 has a chamber length 29 of 6.74 mm in the yarn guiding direction F and a chamber extension 28 of 2.0 mm. This chamber expansion 28 and this chamber length 29 result in a length to expansion ratio of approximately 3.37.

[0124] The chamber walls of chamber regions 2a and 2b each lead away from the walls of the yarn channel at an angle of about 6°. This serves to create many knots

[0125] FIG. 13 shows the injection opening 4 from the embodiment example, from FIG. 12. A smaller part of the cross-section of the injection opening 4 leads into the first chamber region 2a.

[0126] The injection opening 4 has a kite-shaped cross-sectional form with rounded corners and with a rounded boundary in the chamber region 2a.

[0127] The injection opening 4 has a width B of about 1.13 mm and a length L of about 1.1 mm, and thus a width to length ratio of about 1:1.

[0128] The kite shape has an asymmetrical structure: Its length in chamber region 2a is 0.5 mm and in chamber region 2b 0.6 mm.

[0129] With nozzles according to the invention as shown in FIG. 1, comparative tests were made with nozzles as known from the prior art (see, for example, FIG. 14a from WO 2006/099763). In these tests, the operating conditions (in particular the air volume at a given blowing pressure) were adjusted so that, as far as possible, the same account number and knot stability were obtained. FIGS. 14a and 14b show the knot count (FIG. 14a) and knot stability (FIG. 14b) of yarns (PES POY dtex 110/78f36) respectively with a nozzle according to the invention (X45.40) and a nozzle according to the stand (P142). To achieve the almost identical knot count and knot stability, approx. 20% less air was consumed with the nozzle according to the invention.