Textile machine and method for operating same

Abstract

A method and associated textile machine are provided to produce a roving having a protective twist from a fiber bundle fed to a consolidating means. The produced roving is wound with a winding device onto a tube arranged at a winding position. After the wound tube has been fully or partially wound with the roving, a tube change is initiated. During the tube change, the wound tube is removed from the winding position and an empty tube is moved into the winding position. During the tube change, the roving is wound onto the wound tube at least until the roving comes into contact with the empty tube as a result of the tube change such that the production of the roving is not interrupted during the tube change. During the tube change, the roving is wound onto the wound tube in a region that lies outside a region last wound prior to the tube change.

Claims

1. A method for operating a textile machine to produce roving, the method comprising: continuously producing a roving during roving production having a protective twist from a fiber bundle fed to a consolidating means; winding the produced roving with a winding device onto a tube arranged at a winding position; after the tube has been fully or partially wound with the roving, initiating a tube change; during the tube change, removing the wound tube from the winding position and moving an empty tube into the winding position; winding the roving produced by the consolidating means onto the wound tube during the tube change at least until the roving comes into contact with the empty tube and is wound onto the empty tube, wherein the tube change from the wound tube to the empty tube is done without interruption of the continuous production of the roving by the consolidating means; and during the tube change, winding the roving onto the wound tube in a region that lies outside a region last wound prior to the tube change.

2. The method according to claim 1, wherein the consolidating means is an air spinning nozzle, the roving having the protective twist produced from the fiber bundle within the air spinning nozzle by a swirled air flow.

3. The method according to claim 1, wherein a roving delivery speed of the consolidating means during the tube change differs by at most 30% from the roving delivery speed of the consolidating means before or after the tube change.

4. The method according to claim 1, wherein the wound tube and the empty tube rotate about a respective rotation axis during the tube change.

5. The method according to claim 1, wherein during the tube change, the roving is guided by a traversing element that moves in a back and forth path parallel to the rotation axis of the wound tube.

6. The method according to claim 5, wherein after the roving has contacted the empty tube, the roving is cut between the wound tube and the empty tube.

7. The method according to claim 5, wherein immediately before the tube change, the traversing element is moved in the back and forth path between two turning points, and during the tube change the traversing element moves in the back and forth path in a region outside of the turning points.

8. The method according to claim 7, wherein during the tube change, the roving is in contact at least temporarily with both the wound tube and with the empty tube, and the roving is cut when the traversing element is in the region outside of the turning points.

9. The method according to claim 7, wherein immediately after the tube change, the traversing element is moved in the back and forth path between two turning points having a spacing that is greater than a spacing between the two turning points immediately prior to the tube change.

10. The method according to claim 1, wherein the wound tube and the empty tube are held stationary by a tube change device prior to the tube change, and during the tube change are moved by movement of the tube change device.

11. The method according to claim 10, wherein during the tube change, the wound tube is moved from the winding position to a tube removal position and the empty tube is moved from the tube removal position to the winding position.

12. A textile machine for producing a roving, comprising: a consolidating means for producing a roving from a fiber bundle, the roving having a protective twist; a winding device configured to wind the produced roving onto a tube; and a controller that operates the textile machine such that the roving is produced in accordance with the method of claim 1.

13. The textile machine according to claim 12, wherein the winding device comprises at least two rotationally-driven tube holders configured with a movable tube change device, the tube holders movable between a winding position and a tube removal position by movement of the tube change device.

14. The textile machine according to claim 12, wherein the consolidating means comprises an air spinning nozzle, wherein the roving having the protective twist is produced from the fiber bundle within the air spinning nozzle by means of a swirled air flow.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

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

(2) FIGS. 1 to 3 show part of a roving production start procedure on a textile machine in the form of an air-jet spinning machine;

(3) FIGS. 4 to 6 show a perspective part of a winding device of a textile machine according to the invention, in the form of an air-jet spinning machine, during the start of a tube change;

(4) FIGS. 7 to 10 show a side view of part of a winding device of a textile machine according to the invention, in the form of an air-jet spinning machine, toward the end of a tube change; and

(5) FIG. 11 shows part of one possible embodiment of a traversing element.

DETAILED DESCRIPTION

(6) 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.

(7) FIGS. 1 to 3 show a schematic view of part of a textile machine according to the invention in the form of an air-jet spinning machine 1 serving as an example of such a textile machine, which serves to produce a roving 2, at different points in time during a roving production start procedure. The air-jet spinning machine 1 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 4, for example in the form of a doubled-over draw frame sliver. The illustrated air-jet spinning machine 1 also comprises in principle a consolidating means, spaced apart from the drafting system 16, in the form of an air spinning nozzle 3 having an internal vortex chamber (known from the prior art and therefore not shown) and a yarn forming element (likewise known from the prior art and therefore not shown). In the air spinning nozzle 3, the fiber bundle 4 or at least a portion of the fibers of the fiber bundle 4 is provided with a protective twist.

(8) The air-jet spinning machine 1 may also comprise a draw-off unit 18 comprising preferably two draw-off rollers 19 for the roving 2 (the draw-off unit 18 is not absolutely necessary). A winding device 5 arranged downstream of the draw-off unit 18 is also usually present, which winding device in turn should comprise at least one tube drive 28 (only shown in FIGS. 1 to 4) and in each case a tube holder 14 which is connected to the tube drive 28 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 28.

(9) In the embodiment according to the invention, the winding device 5 has at least two tube holders 14, as can be seen below in connection with FIGS. 4 to 10, so that, besides a tube holder 14 for a tube 7 that is currently being wound during operation of the air-jet spinning machine 1, one or more further tube holders 14 for empty tubes 7 may be present.

(10) The air-jet spinning machine 1 shown as an example of a textile machine according to the invention operates according to a special air-jet spinning process. In order to form the roving 2, the fiber bundle 4 is guided in a transport direction T via an inlet opening (not shown) into the vortex chamber of the air spinning nozzle 3. There, it is given a protective twist, that is to say at least a portion of the fibers of the fiber bundle 4 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 4 and is wound around the tip of a yarn forming element which protrudes into the vortex chamber.

(11) Finally, the fibers of the fiber bundle 4 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 2 which has the desired protective twist.

(12) Due to the only partial twisting of the fibers, the roving 2 has a draftability which is essential for the further processing of the roving 2 in a downstream spinning machine, for example a ring spinning machine. Conventional air-jet spinning devices, on the other hand, give the fiber bundle 4 such a pronounced twist that the requisite drafting following yarn production is no longer possible. This is also desired in this case since conventional air-jet spinning machines 1 are designed to produce a finished yarn, which is generally intended to be characterized by a high strength.

(13) Before a tube 7 can be wound with roving 2, a start procedure must take place, during which the roving 2 leaving the air spinning nozzle 3 is brought into contact with the tube 7. Part of a possible start procedure is shown in FIGS. 1 to 3.

(14) Firstly, a fiber bundle 4 is fed into the air spinning nozzle 3 by starting the drafting system 16. The above-described roving production, during which the fiber bundle 4 is given a protective twist, takes place in the air spinning nozzle 3. Finally, the roving 2 leaves the air spinning nozzle 3 via an exit opening (not shown in said figures) and is grasped by the air flow of a suction unit 24. The suction unit 24 preferably has a suction nozzle 23 with a suction opening 20, via which air and thus also the roving 2 leaving the air spinning nozzle 3 can be sucked up or sucked in. In this stage shown in FIG. 1, therefore, the roving 2 produced by the air spinning nozzle 3 leaves the air spinning nozzle 3 and is sucked into the suction unit 24 via the suction opening 20, wherein the delivery speed of the air spinning nozzle 3 preferably corresponds to the delivery speed prevailing after the start procedure or is only slightly lower than said speed.

(15) 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 3 is active and, if present, the draw-off unit 18 is active (that is to say is drawing a roving 2 out of the air spinning nozzle 3), so that a particularly high efficiency of the illustrated air-jet spinning machine 1 can be ensured.

(16) An illustrated controller 22 is also provided, which is operatively connected to the described elements of the air-jet spinning machine 1 in order to carry out inter alia the described start procedure and the tube change that will be described below. The controller 22 may be present for each spinning position of the air-jet spinning machine 1. It is also conceivable that one controller 22 is responsible for a plurality of spinning positions.

(17) In the next step (see FIG. 2), the suction unit 24 is moved (preferably the suction nozzle 23 is pivoted about a pivot axis 25) into a transfer position in which the suction opening 20 and thus also a section of the roving 2 (which is moreover still being delivered by the air spinning nozzle 3) are located in the region of the tube surface. Contact between the tube 7 and the roving 2 preferably does not yet exist at this stage.

(18) While the suction unit 24 is assuming its position shown in FIG. 2 (or shortly thereafter), the traversing element 9 of a traversing unit 21 is moved into the position shown schematically in FIG. 3, in which the roving 2 is grasped and guided by the traversing element 9. The traversing unit 21 thereby moves the roving 2 into the vicinity of the tube 7 or brings about direct contact between the tube 7 and the roving 2, so that the roving 2 (preferably under the effect of suitable rough surface sections of the tube 7) is grasped by the tube 7.

(19) At the same time or shortly thereafter, a cutting unit is finally activated, which comprises for example a movable (preferably pivotable) cutting element 26. The cutting element 26 is thereby brought into contact with the roving 2, preferably with the section thereof that is located between the traversing unit 21 and the suction opening 20. At this moment, a local decelerating of the roving 2 occurs in the region which comes into contact with the cutting unit, so that the roving 2 finally tears between the tube 7 and the cutting unit since it continues to be wound up by the rotating tube 7, that is to say has a tensile force applied to it. Due to the tearing of the roving 2, a section of the roving 2 on the suction unit side is obtained, which can be conveyed away via the suction unit 24. 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 3 and the tube 7.

(20) By virtue of the further rotation of the tube 7, the roving 2 still being delivered by the air spinning nozzle 3 is continuously wound onto the tube 7, wherein the traversing element 9, by virtue of a movement in the direction of the rotation axis 8 of the tube 7, ensures that the roving 2 is uniformly wound onto the tube 7. At this stage in which the cutting element 26 and also the suction unit 24 have assumed their original positions, the air-jet spinning machine 1 is finally in its normal mode following the roving production start procedure, in which normal mode the tube 7 is wound with roving 2 until the desired bobbin size is achieved.

(21) The necessary tube change according to the invention will now be described below.

(22) In this connection, FIGS. 4 to 6 show part of the winding device 5 of the air-jet spinning machine 1, which in principle comprises two (or if necessary even more) tube holders 14, by means of which in each case one bobbin can be fixed. Each of the tube holders 14 can be set in a rotational movement via a tube drive 28 in order to be able to set the individual tubes 7 in a rotational movement, preferably independently of one another. Furthermore, the tube holders 14 are part of a tube change device 15 which can likewise be set in a rotational movement via a drive 13 (for example with the interposition of a belt 29 or other transmission means), wherein the rotation axis of the tube change device 15 preferably runs parallel to the rotation axis 8 of the tubes 7.

(23) FIG. 4 shows the stage after the described start procedure, in which the tube 7 is sufficiently wound with roving 2 and a tube change is pending, wherein at this point in time roving 2 that is still being delivered by the air spinning nozzle 3 is being wound onto the tube in a manner traversed by the traversing element 9 (the traversing movement here takes place in principle in the direction of the double-headed arrow).

(24) Once the tube change has been initiated by the controller 22, the tube change device 15 begins to rotate during ongoing roving production, so that the wound tube 7, onto which roving 2 is still being wound, is moved from the winding position 6 into the region of a tube removal position 12 (cf. FIGS. 4 to 6, wherein the tube change device 15 rotates continuously in the clockwise direction). At the same time, an empty tube 7 is moved from the tube removal position 12 into the region of the winding position 6.

(25) The moment of the tube change shown in FIG. 4 is shown in side view in FIG. 7, wherein only the sections relevant to what is stated below are shown. In addition, the empty tube 7 arriving in the region of the winding position 6 in FIG. 7 is provided with an adhesive strip 27, which in principle should be present on all the tubes 7 shown in the individual figures (even though this is not shown in all the figures).

(26) In any case, it is advantageous if the traversing element 9 is moved back and forth between two turning points 10, 11 until the start of the tube change or until the moment shown in FIG. 7, wherein the position of the turning points 10, 11 can be moved in relation to one another during the winding process 5 so that ultimately the outer contour of the wound tube 7 shown in FIGS. 4 to 10 is obtained.

(27) During the tube change, the traversing element 9 is moved upward such that it is located outside the two turning points 10, 11 at which the traversing element 9 has performed a change of direction prior to the tube change. The movement in question can be seen from a comparison of FIGS. 7 and 8. This has the advantage that the roving 2 enters into the region of the adhesive strip 27 of the empty tube 7 and can be grasped thereby. At the same time, the movement of the traversing element 9 means that the roving 2 is no longer wound onto the cylindrical region of the wound tube 7 lying inside the turning points 10, 11. Instead, the roving 2 is wound around the conical region located above the first turning point 10, wherein this winding takes place in a helical manner.

(28) In the stage shown in FIG. 9, the roving 2 is finally cut between the wound and the empty tube 7, preferably by means of the aforementioned cutting element 26 (shown only schematically by a pair of scissors). The end of the roving 2 located on the wound tube 7 is finally wound onto the wound tube 7, while the end of the roving 2 in contact with the empty tube 7, which end is formed after the cutting process, is wound onto the tube 7 that is empty at the start of the change process (see FIG. 10).

(29) In the last step, the wound tube 7 can then be removed from the winding device 5 and replaced by an empty tube 7. The winding device 5 is then ready for a new tube change, which is performed as soon as the tube 7 located in the region of the winding position 6 has reached the required bobbin size.

(30) Finally, FIG. 11 shows part of one possible embodiment of the traversing element 9 in the form of a pressing finger already mentioned in the above description (FIG. 11 shows a plan view). The traversing element 9 comprises in principle a preferably rod-shaped wrapping section 30, around which the roving 2 is wrapped multiple times during the process of winding onto the tube 7 (the wrapping may be produced for example by rotating the wrapping section 30 about its longitudinal axis and/or by rotating a gripper 31 about said axis). The traversing element 9 further comprises a guide surface 32 for the roving 2, which guide surface during the winding process is pressed by means of a drive (not shown) against the tube 7 or the outermost position of the roving 2 wound onto the latter. As a result, a tension is introduced into the roving 2 as a result of the wrapping and the associated friction between the wrapping section 30 and the roving 2, which tension permits a tight winding of said roving onto the tube 7. A tearing of the roving 2 is prevented here by the fact that the guide surface 32 bears against the tube 7 or the outermost position of the roving 2 wound onto the latter (for further details in this regard, reference is made to the above description).

(31) 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

(32) 1 air-jet spinning machine 2 roving 3 air spinning nozzle 4 fiber bundle 5 winding device 6 winding position 7 tube 8 rotation axle 9 traversing element 10 first turning point of the traversing element 11 second turning point of the traversing element 12 tube removal position 13 drive of the tube change device 14 tube holder 15 tube change device 16 drafting system 17 drafting system roller 18 draw-off unit 19 draw-off roller 20 suction opening 21 traversing unit 22 controller 23 suction nozzle 24 suction unit 25 pivot axle of the suction nozzle 26 cutting element 27 adhesive strip 28 tube drive 29 belt 30 wrapping section 31 gripper 32 guide surface A spacing between the turning points of the traversing element T transport direction