Textile Machine for Producing Roving and Method for Starting the Roving Production on a Corresponding Textile Machine

Abstract

The invention relates to a textile machine for producing roving (1), comprising at least one consolidating means, by which a roving (1) having a protective twist can be produced from a fiber bundle (3) that is fed to the consolidating means, and comprising a winding device (5), arranged downstream of the consolidating means in a transport direction (T) of the roving (1), for winding the roving (1) produced by the consolidating means onto a tube (7) which can be driven by a tube drive (6). The textile machine is characterized in that it has an arrangement by which the roving (1) leaving the consolidating means during a start of roving production can be brought into contact with the tube (7), wherein said arrangement comprises a movably mounted suction unit (8) with a suction opening (9), by means of which the roving (1) can be sucked up during ongoing roving production, wherein said arrangement comprises means by which the roving (1) running between the consolidating means and the suction opening (9) can be brought into contact with the tube (7) during ongoing roving production, and in that said arrangement comprises means by which the roving (1), during ongoing roving production, can be cut such that the section (19) of the roving (1) that is grasped by the suction unit (8) can be conveyed away by the suction unit (8) and the section of the roving (1) running between the consolidating means and the tube (7) can be wound onto the tube (7). A method for starting roving production on such a textile machine is also proposed.

Claims

1. A textile machine for producing roving (1), comprising at least one consolidating means by which a roving (1) having a protective twist can be produced from a fiber bundle (3) that is fed to the consolidating means, and comprising a winding device (5), arranged downstream of the consolidating means in a transport direction (T) of the roving (1), for winding the roving (1) produced by the consolidating means onto a tube (7) which can be driven by a tube drive (6), characterized in that the textile machine has an arrangement by which the roving (1) leaving the consolidating means during a roving production start procedure can be brought into contact with the tube (7), wherein said arrangement comprises a movably mounted suction unit (8) with a suction opening (9), by means of which the roving (1) can be sucked up during ongoing roving production, wherein said arrangement comprises means by which the roving (1) running between the consolidating means and the suction opening (9) can be brought into contact with the tube (7) during ongoing roving production, and in that said arrangement comprises means by which the roving (1), during ongoing roving production, can be cut such that the section (19) of the roving (1) that is grasped by the suction unit (8) can be conveyed away by the suction unit (8) and the section of the roving (1) running between the consolidating means and the tube (7) can be wound onto the tube (7).

2-15. (canceled)

Description

[0034] Further advantages of the invention are described in the following exemplary embodiments, in which:

[0035] FIGS. 1 to 5 show a roving production start procedure according to the invention on a schematically shown textile machine according to the invention, in the form of an air-jet spinning machine, which serves to produce roving, and

[0036] FIGS. 6 and 7 show a front view of a suction unit of a textile machine according to the invention, in the form of an air-jet spinning machine, in two different positions.

[0037] First, it should be expressly pointed out that the air-jet spinning machine that is shown and described as an example of a textile machine according to the invention, as well as the illustrated components thereof, are not shown true to scale. Instead, the individual figures show only schematic diagrams which are intended to illustrate the basic structure of the respective assemblies. In particular, the mutual spacings and spatial relationships between the individual elements may differ from what is shown.

[0038] FIGS. 1 to 5 show a schematic view of part of a textile machine according to the invention in the form of an air-jet spinning machine, which serves to produce a roving 1, at different points in time during a roving production start procedure. The air-jet spinning machine may if necessary comprise a drafting system 16 comprising a plurality of corresponding drafting system rollers 17 (only one of the drafting system rollers 17 has been provided with a reference sign for clarity reasons), to which there is fed a fiber bundle 3, for example in the form of a doubled-over draw frame sliver. The illustrated air-jet spinning machine also comprises in principle a consolidating means, spaced apart from the drafting system 16, in the form of an air spinning nozzle 2 having an internal vortex chamber (known from the prior art and therefore not shown) in which the fiber bundle 3 or at least a portion of the fibers of the fiber bundle 3 is provided with a protective twist.

[0039] The air-jet spinning machine may also comprise a draw-off unit 4 comprising preferably two draw-off rollers 18, as well as a winding device 5 for the roving 1 which is arranged downstream of the draw-off unit 4 (the draw-off unit 4 is therefore not absolutely necessary). The winding device 5 in turn comprises preferably a tube drive 6 and a tube holder 21 which is connected to the tube drive 6 and is known in principle, by means of which a tube 7 can be fixed and can be set in a rotational movement by means of the tube drive 6.

[0040] The air-jet spinning machine operates according to a special air-jet spinning process. In order to form the roving 1, the fiber bundle 3 is guided in a transport direction T via an inlet opening (not shown) into the vortex chamber of the air spinning nozzle 2. There, it is given a protective twist, that is to say at least a portion of the fibers of the fiber bundle 3 is grasped by a swirled air flow which is created by suitably placed air nozzles. A portion of the fibers is thereby pulled at least a little way out of the fiber bundle 3 and is wound around the tip of a yarn forming element which protrudes into the vortex chamber.

[0041] Finally, the fibers of the fiber bundle 3 are drawn out of the vortex chamber via an inlet mouth of the yarn forming element and a draw-off channel which is arranged inside the yarn forming element and adjoins the inlet mouth. In doing so, the free fiber ends are finally also drawn on a helical trajectory in the direction of the inlet mouth and wrap as wrapping fibers around the centrally running core fibers, resulting in a roving 1 which has the desired protective twist.

[0042] Due to the only partial twisting of the fibers, the roving 1 has a (residual) draftability which is essential for the further processing of the roving 1 in a downstream spinning machine, for example a ring spinning machine. Conventional air-jet spinning devices, on the other hand, give the fiber bundle 3 such a pronounced twist that the required drafting following yarn production is no longer possible. This is also desired in this case since conventional air-jet spinning machines are designed to produce a finished yarn, which is generally intended to be characterized by a high strength.

[0043] Before a tube 7 can be wound with roving 1, a start procedure must take place, during which the roving 1 leaving the air spinning nozzle 2 must be brought into contact with the tube 7. One possible start procedure according to the present invention is shown in FIGS. 1 to 5.

[0044] Firstly, a fiber bundle 3 is fed into the air spinning nozzle 2 by starting the drafting system 16. The above-described roving production, during which the fiber bundle 3 is given a protective twist, takes place in the air spinning nozzle 2. Finally, the roving 1 leaves the air spinning nozzle 2 via an exit opening 20 (not shown in said figures) and is grasped by the air flow of a suction unit 8. The suction unit 8 preferably has a suction nozzle 13 with a suction opening 9, via which air and thus also the roving 1 leaving the air spinning nozzle 2 can be sucked up or sucked in. In this stage shown in FIG. 1, therefore, the roving 1 produced by the air spinning nozzle 2 leaves the air spinning nozzle 2 and is sucked into the suction unit 8 via the suction opening 9 (which is located, for example, in the region of the draw-off unit 4 that is preferably present or in the region of the exit opening 20 of the air spinning nozzle 2, cf. FIG. 6), wherein the delivery speed of the air spinning nozzle 2 preferably corresponds to the delivery speed prevailing after the start procedure or is only slightly lower (preferably at most 20% lower) than said speed.

[0045] In general, it should be noted at this point that the entire start procedure preferably takes place without any break in roving production or roving delivery, that is to say while the drafting system 16 is active, the air spinning nozzle 2 is active and, if present, the draw-off unit 4 is active (that is to say is drawing a roving 1 out of the air spinning nozzle 2), so that a particularly high efficiency of the illustrated air spinning machine can be ensured.

[0046] An illustrated control unit 15 is also provided, which is operatively connected to the described elements of the air-jet spinning machine in order to carry out the roving production start procedure according to the invention. The control unit 15 may be present for each spinning position of the air-jet spinning machine. It is also conceivable that one control unit 15 is responsible for a plurality of spinning positions.

[0047] In the next step (see FIG. 2), the suction unit 8 is moved (preferably pivoted about a pivot axle or rotation axle 14) into a transfer position in which the suction opening 9 and thus also a section of the roving 1 (which is moreover still being delivered by the air spinning nozzle 2) are located in the region of the tube surface. Contact between the tube 7 and the roving 1 preferably does not yet exist at this stage.

[0048] While the suction unit 8 is assuming its position shown in FIG. 2 (or shortly thereafter), the traversing unit 10 is moved into the position shown schematically in FIG. 3, in which the roving 1 is grasped and guided by the traversing unit 10. The traversing unit 10 thereby moves the roving 1 into the vicinity of the tube 7 or brings about direct contact between the tube 7 and the roving 1, during which the roving 1 (preferably under the effect of suitable rough surface sections of the tube 7) is grasped by the tube 7.

[0049] At the same time or shortly thereafter, a cutting unit 11 is finally activated, which comprises for example a movable (preferably pivotable) cutting arm 12. The cutting unit 11 is thereby brought into contact with the roving 1, preferably with the section thereof that is located between the traversing unit 10 and the suction opening 9. At this moment, a local decelerating of the roving 1 occurs in the region which comes into contact with the cutting unit 11, so that the roving 1 finally tears between the tube 7 and the cutting element since it continues to be wound up by the rotating tube 7, that is to say has a tension applied to it (see FIG. 4). Due to the tearing of the roving 1, a section of the roving 1 on the suction unit side is obtained, which can be conveyed away via the suction unit 8 (said section of the roving 1 that is located in the suction unit 8 after the cutting of the roving 1 is provided with reference number 19 in FIG. 4). A roving section on the air spinning nozzle side is also obtained, which is already grasped by the tube 7 and extends between the air spinning nozzle 2 and the tube 7.

[0050] By virtue of the further rotation of the tube 7, the roving 1 still being delivered by the air spinning nozzle 2 is continuously wound onto the tube 7, wherein the traversing unit 10, by virtue of a movement in the direction of the rotation axle of the tube 7 (see arrow C), ensures that the roving 1 is uniformly wound onto the tube 7 (see FIG. 5). At this stage in which the cutting unit 11 and also the suction unit 8 have assumed their original positions, the air-jet spinning machine is finally in its normal operating mode following the start procedure, in which normal operating mode the tube 7 is wound with roving 1 until the desired bobbin size is achieved.

[0051] One advantageous embodiment of the suction unit 8 or the suction nozzle 13 thereof is shown in FIGS. 6 and 7, wherein FIG. 6 shows the sucking position (that is to say the position in which the roving 1 is being sucked up after leaving the exit opening 20 of the air spinning nozzle 2cf. FIG. 1) and FIG. 7 shows the transfer position (that is to say the position shown in FIG. 2, in which the roving 1 has been moved into the vicinity of the tube 7) (the roving 1 is not shown in FIGS. 6 and 7).

[0052] As can be seen from these figures, it may be advantageous if the suction nozzle 13 of the suction unit 8 is mounted such as to be able to move about a rotation axle 14 which encloses with the horizontal an angle which is other than 0 and is for example between 0 and 30, preferably between 0 and 20, particularly preferably between 0 and 15. The suction nozzle 13 can thus be pivoted obliquely downward in order to position the roving 1 to the side of the tube 7.

[0053] The present invention is not limited to the exemplary embodiments that have been shown and described. Modifications within the scope of the claims are also possible, as is any combination of the described features, even if they are shown and described in different parts of the description or the claims or in different exemplary embodiments.

LIST OF REFERENCE SIGNS

[0054] 1 roving [0055] 2 air spinning nozzle [0056] 3 fiber bundle [0057] 4 draw-off unit [0058] 5 winding device [0059] 6 tube drive [0060] 7 tube [0061] 8 suction unit [0062] 9 suction opening [0063] 10 traversing unit [0064] 11 cutting unit [0065] 12 cutting arm [0066] 13 suction nozzle [0067] 14 rotation axle [0068] 15 control unit [0069] 16 drafting system [0070] 17 drafting system roller [0071] 18 draw-off roller [0072] 19 section of the roving that is located in the suction unit after the roving has been [0073] cut [0074] 20 exit opening [0075] 21 tube holder [0076] T transport direction [0077] angle between the rotation axle of the suction nozzle and the horizontal