Spinning station of an air jet spinning machine

Abstract

A spinning position on an air-jet spinning machine has a yarn-forming element extending at least partially into the turbulence chamber; and air jets directed into the turbulence chamber to impart to the fiber strand a twist in the area of an intake mouth of the yarn-forming element. A guide arrangement for guiding the fiber strand is situated in the area of the inlet port of the turbulence chamber and comprises at least two guide sections spaced a distance apart from one another, their mutual spacing decreasing in at least some sections in the direction of conveyance of the fiber strand. The guide arrangement also comprises at least one central guide element, which extends at least partially between the guide sections in a section running perpendicular to the longitudinal axis of the draw-off channel and produces a deflection of the fibers of the fiber strand perpendicular to the longitudinal axis of the draw-off channel.

Claims

1. A spinning position on an air-jet spinning machine, which serves to produce a yarn from a fiber strand consisting of fibers, comprising: a turbulence chamber with an inlet port for the fiber strand entering the turbulence chamber in a direction of conveyance during operation of the air-jet spinning machine; a yarn-forming element extending into the turbulence chamber, the yarn-forming element having an intake mouth and a draw-off channel through which yarn is drawn off out of the turbulence chamber; air jets directed into the turbulence chamber, the air jets opening into the turbulence chamber in a wall surrounding the turbulence chamber, such that air can be introduced through these jets into the turbulence chamber in a predefined direction to impart to the fiber strand a twist in the area of an intake mouth of the yarn-forming element; a guide arrangement situated in the area of the inlet port of the turbulence chamber, the guide arrangement further comprising at least two guide sections spaced a distance apart from one another that decreases in at least some sections in the direction of conveyance of the fiber strand; the guide arrangement further comprising at least one central guide element that extends at least partially between the guide sections viewed in a section running perpendicular to a longitudinal axis of the draw-off channel and producing a deflection of the fibers of the fiber strand perpendicular to the longitudinal axis of the draw-off channel; and wherein the guide sections are formed by one of mandrels or guide plates that extend from a wall surrounding the inlet port of the turbulence chamber towards the inlet mouth of the yarn-forming element.

2. The spinning position according to claim 1, wherein the central guide element runs along one of the longitudinal axis of the draw-off channel or a central longitudinal axis of the inlet port of the turbulence chamber.

3. The spinning position according to claim 2, wherein the longitudinal axis of the draw-off channel is collinear with the central longitudinal axis of the inlet port of the turbulence chamber.

4. The spinning position according to claim 1, wherein an end of the central guide element oriented towards the outlet port of the draw-off channel is positioned between the intake mouth of the yarn-forming element and the inlet port of the turbulence chamber.

5. The spinning position according to claim 1, wherein the central guide element extends further in a direction towards the outlet port of the draw-off channel than the guide sections.

6. The spinning position according to claim 1, wherein one or both of the guide sections and the central guide element extend into the draw-off channel.

7. The spinning position according to claim 1, wherein a minimal distance between the guide sections is greater than a minimal distance between the guide sections and the central guide element facing the outlet port of the draw-off channel.

8. The spinning position according to claim 1, wherein the guide sections each have a first end towards the outlet port of the draw-off channel and an opposite end away from the outlet port of the draw-off channel, the central guide element having a first end towards the outlet port of the draw-off channel with a section running parallel to a longitudinal axis of the draw-off channel between the first ends of the guide sections.

9. The spinning position according to claim 1, wherein the central guide element has a first end towards the outlet port of the draw-off channel, the guide sections each have a first end towards the outlet port of the draw-off channel, wherein the first ends of the guide sections are arranged concentrically around the first end of the central guide element view in a section that is perpendicular to a longitudinal axis of the draw-off channel.

10. A spinning position on an air-jet spinning machine, which serves to produce a yarn from a fiber strand consisting of fibers, comprising: a turbulence chamber with an inlet port for the fiber strand entering the turbulence chamber in a direction of conveyance during operation of the air-jet spinning machine; a yarn-forming element extending into the turbulence chamber, the yarn-forming element having an intake mouth and a draw-off channel through which yarn is drawn off out of the turbulence chamber; air jets directed into the turbulence chamber, the air jets opening into the turbulence chamber in a wall surrounding the turbulence chamber, such that air can be introduced through these jets into the turbulence chamber in a predefined direction to impart to the fiber strand a twist in the area of an intake mouth of the yarn-forming element; a guide arrangement situated in the area of the inlet port of the turbulence chamber, the guide arrangement further comprising at least two guide sections spaced a distance apart from one another that decreases in at least some sections in the direction of conveyance of the fiber strand; the guide arrangement further comprising at least one central guide element that extends at least partially between the guide sections viewed in a section running perpendicular to a longitudinal axis of the draw-off channel and producing a deflection of the fibers of the fiber strand perpendicular to the longitudinal axis of the draw-off channel; and wherein a minimal distance between the guide sections is less than a diameter of the draw-off channel in an area of the intake mouth of the yarn-forming element.

11. The spinning position according to claim 1, wherein the guide sections define an angle relative to a longitudinal axis of the draw-off channel between 10 degrees and 50 degrees.

12. A spinning position on an air-jet spinning machine, which serves to produce a yarn from a fiber strand consisting of fibers, comprising: a turbulence chamber with an inlet port for the fiber strand entering the turbulence chamber in a direction of conveyance during operation of the air-jet spinning machine; a yarn-forming element extending into the turbulence chamber, the yarn-forming element having an intake mouth and a draw-off channel through which yarn is drawn off out of the turbulence chamber; air jets directed into the turbulence chamber, the air jets opening into the turbulence chamber in a wall surrounding the turbulence chamber, such that air can be introduced through these jets into the turbulence chamber in a predefined direction to impart to the fiber strand a twist in the area of an intake mouth of the yarn-forming element; a guide arrangement situated in the area of the inlet port of the turbulence chamber, the guide arrangement further comprising at least two guide sections spaced a distance apart from one another that decreases in at least some sections in the direction of conveyance of the fiber strand; the guide arrangement further comprising at least one central guide element that extends at least partially between the guide sections viewed in a section running perpendicular to a longitudinal axis of the draw-off channel and producing a deflection of the fibers of the fiber strand perpendicular to the longitudinal axis of the draw-off channel; and wherein in the absence of a fiber strand, the guide sections touch each other or the central guide element.

13. The spinning position according to claim 1, wherein the guide sections and the central guide element are formed in an insert that is supported relative to the turbulence chamber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Additional advantages of the invention are described in the following exemplary embodiments, in which:

(2) FIG. 1 shows a detail of a partially cutaway spinning position on an air-jet spinning machine;

(3) FIG. 2 shows a sectional diagram of a detail of a known spinning position on an air-jet spinning machine;

(4) FIGS. 3A and 3B show a detail of a sectional diagram of an air-jet spinning machine according to the invention (FIG. 3A) and a sectional diagram along the sectional face A-A (FIG. 3B);

(5) FIG. 4 shows the area of the inlet port of the turbulence chamber of a spinning position according to the invention; and

(6) FIGS. 5 to 9 show alternative embodiments of the area shown in FIG. 4.

DETAILED DESCRIPTION

(7) Reference will now be made to embodiments of the invention, one or more examples of which are shown in the drawings. Each embodiment is provided by way of explanation of the invention, and not as a limitation of the invention. For example features illustrated or described as part of one embodiment can be combined with another embodiment to yield still another embodiment. It is intended that the present invention include these and other modifications and variations to the embodiments described herein.

(8) FIG. 1 shows a schematic view of a detail of an air-jet spinning machine. The air-jet spinning machine may comprise, as needed, a drawing frame 25, which is supplied with a fiber strand 2, for example, in the form of a doubled drawing frame sliver. Furthermore, the air-jet spinning machine shown here has a plurality of spinning positions 22 situated next to one another, each having an interior turbulence chamber 3, in which the fiber strand 2 and/or at least some of the fibers of the fiber strand 2 are provided with a twist (the precise mechanism of action of the spinning position 22 is described in greater detail below).

(9) In addition, the air-jet spinning machine may comprise a draw-off roll pair 26 and a winding device 27 (also shown schematically) downstream from the draw-off roll pair 26 with a bobbin 28 for winding the yarn 1 having the desired twist on exiting the spinning position 22. The device according to the invention need not necessarily have a drawing frame 25, as illustrated in FIG. 1. The draw-off roll pair 26 is also not absolutely necessary.

(10) The spinning machine shown here operates according to an air-jet spinning process. To form the yarn 1, the fiber strand 2 is guided over a fiber guide element 24, which is equipped with an inlet port into the turbulence chamber 3 of the spinning position 22 (see also FIG. 2), where a type of twist is imparted to the fiber strand, i.e., at least some of the free fiber ends 23 of the fiber strand are caught up by an air stream generated by air jets 6 situated accordingly in a wall 21 surrounding the turbulence chamber 3. Some of the fibers are extracted at least a short distance from the fiber strand 2 in this process and are wrapped around the tip of a yarn-forming element 5 protruding into the turbulence chamber 3. Due to the fact that the fiber strand 2 is pulled out of the turbulence chamber 3 through an intake mouth 7 of the yarn-forming element 5 over a draw-off channel 8 situated inside the yarn-forming element 5, ultimately the free fiber ends 23 (see FIG. 1) are also drawn in the direction of the intake mouth 7 and are wrapped as so-called wrap fibers around the core fibers running centrallyresulting in a yarn 1 having the desired twist.

(11) It should be pointed out here in general that the yarn 1 thus produced may fundamentally be any type of fiber strand, which is characterized in that an exterior portion of the fibers (so-called wrap fibers) is wrapped around an interior portion of the fibers, preferably without a twist, to impart the desired strength to the yarn 1. The invention thus also includes an air-jet spinning machine, which can produce a so-called roving. Roving is yarn 1 having a relatively small number of wrap fibers, or a yarn 1 in which the wrap fibers are wrapped relatively loosely around the inner core, so that the yarn 1 remains drawable. This is crucial if the yarn 1 thus produced should or must be drawn again on a downstream textile machine (a ring spinning machine, for example) with the help of a drawing frame 25 in order to be able to process it further accordingly.

(12) With regard to the air jets 6, it should be pointed out here as a precaution that these air jets should usually be oriented so that all of the streams of air exiting the air jets are aimed in the same direction in order to jointly produce a unidirectional stream of air with one direction of twist. The individual air jets 6 here are preferably arranged in rotational symmetry to one another.

(13) The spinning positions 22 known in the prior art preferably have a twist retaining element 29, which is inserted into the fiber guide element 24, for example. As shown in FIG. 2, this may be designed as a pin, around which the fibers are partially wrapped, and it prevents a twist in the fiber strand 2 from being propagated in a direction opposite the direction of conveyance of the fiber strand 2 and thus in the direction of the inlet port 4 of the fiber guide element 24.

(14) However, since the pin shown here or other comparable, centrally arranged elements can always act only from the inside on the fiber strand 2 surrounding the twist retaining element 29, the effect of the same is limited. Furthermore, there is a mechanical load on the fibers, which undergo a lateral deflection in the area of the twist retaining element 29 that is not negligible.

(15) In contrast with that, the spinning position 22 according to the invention has only one novel guide arrangement 9, which causes a reverse propagation of the twist in the direction opposite the direction of conveyance of the fiber strand 2, without thereby reducing the number of desired wrap fibers excessively.

(16) As shown in FIGS. 3A and 3B, the guide arrangement 9 now has at least two guide sections 10 spaced a distance apart from one another (there are four in FIG. 3), the mutual spacing of which decreases in the direction of conveyance of the fiber strand 2 (in at least some sections). In other words, the spinning position 22 has a plurality of elements acting on the fiber strand 2 from the outside, these elements converging toward one another in the direction of conveyance of the fiber strand 2. The fiber strand 2 therefore necessarily comes in contact with the guide sections 10 and is captured by them from the outside, so to speak, thereby preventing a twisting of same in the area of the guide sections 10.

(17) However, to ensure that partial separation of the external fiber ends 23 is possible despite the fiber guidance acting from the outside in order to form the desired wrap fibers, it is also provided that the guide arrangement 9 additionally comprises at least one central guide element 11, which extends at least partially between the guide sections 10 in a section running perpendicular to the longitudinal axis 12 of the draw-off channel 8 (see bottom diagram in FIG. 3). Whereas the outer guide sections 10 cause guidance of the fiber strand 2 from the outside, the central guide element 11 is situated in the interior of the fiber strand 2 to a certain extent during yarn production and thus causes the fiber strand to be forced open. In other words, the fibers are deflected outward due to the central guide element 11 or, to put it in geometric terms, the fibers are deflected at a right angle to the longitudinal axis 12 of the draw-off channel 8. The free fiber ends 23 are also forced outward to a greater extent in this way, which ensures that, despite the outer guide sections 10, the fibers enter the area of the air stream created by the air jets 6 and can be wrapped around the fiber core.

(18) Whereas FIG. 3 serves mainly to illustrate the invention in principle, FIGS. 4 through 9 show different examples of the alignment, design and mutual arrangement of the guide sections 10 and the central guide element 11.

(19) Whereas the guide sections 10, which are preferably situated concentrically around the central guide element 11 in the sectional diagram shown at the bottom of FIG. 3, and also the central guide element 11 may also be positioned outside of the yarn-forming element 5 (FIG. 4), it is also conceivable that either the guide sections 10 (FIG. 5) or the central guide element 11 (FIG. 6) extends into the draw-off channel 8 of the yarn-forming element 5.

(20) Furthermore, the central guide element 11 need not necessarily be in the form of a guide mandrel 15 that is provided with a tip, as shown in FIGS. 3A and 3B, for example. Other embodiments are also conceivable instead. Thus the central guide element 11 may have a droplet-shaped or spherical end, for example, as shown in FIG. 7. This would result in a particularly strong lateral deflection of the fibers and thus an increased number of wrap fibers.

(21) The shape and orientation of the guide sections 10 are not limited in principle to one specific embodiment. Thus, for example, instead of the rod-shaped guide sections 10 shown in FIG. 4, it would be conceivable to also use the guide plates 14 indicated in FIG. 8, which also prevent a reverse twist of the fiber strand 2 in the direction opposite the direction of conveyance.

(22) With regard to the guide mandrels 15 shown here, it should also be pointed out that these should preferably form an angle with the longitudinal axis 12 of the draw-off channel 8 (for reasons of simplicity, this angle is identifiable only in FIG. 5, where the wall runs parallel to the longitudinal axis 12 around the inlet port 4). The size of this angle amounts to a value between 10 and 50, preferably a value between 20 and 40, especially preferably a value between 25 and 35.

(23) It is also advantageous in general if the end 18 of the central guide element 11 facing the outlet port 17 of the draw-off channel 8 is situated in a section running parallel to the longitudinal axis 12 of the draw-off channel 8 (corresponding to the diagrams according to FIGS. 4 through 9) between the ends 19 of the guide sections 10 facing the outlet port 17 of the draw-off channel 8 and the ends 20 of same facing away from the outlet port 17 of the draw-off channel 8. This ensures that the fiber strand 2 is in contact simultaneously with the outer guide sections 10 and the central guide element 11, at least in a partial section of the guide arrangement 9.

(24) It should also be pointed out here that the central guide element 11 (and/or its end 18 facing the outlet port 17 of the draw-off channel 8) should run on the longitudinal axis 12 of the draw-off channel 8, which may in turn be situated to be colinear with the central axis 13 of the inlet port 4. The fiber strand 2 thus encounters the central guide element 11 centrally and is deflected laterally accordingly because it must pass by the central guide element 11.

(25) Finally, as shown by a comparison of FIG. 9 with FIG. 6, for example, the guide sections 10 and/or the central guide element 11 may be directed away from the wall 16 surrounding the inlet port 4 in the direction of the yarn-forming element 5, for example. Alternatively, however, it is also possible to affix the guide sections 10 and/or the central guide element 11 in another location. For example, an insert 30 (having a sleeve-shaped design, for example), as indicated in FIG. 9 might be used, surrounding the guide sections 10 and/or the central guide element 11 or with the aforementioned components being attached to it.

(26) The present invention is not limited to the exemplary embodiment depicted and described here. Modifications within the context of the patent claims are also possible, such as a combination of the features, even if they are illustrated and described in different exemplary embodiments.