EP3511275A1 - Textile machine and method for automatically applying a thread at a working point of a textile machine - Google Patents

Abstract

In a method for automatic attachment of a thread (4) at a workstation (2) of a textile machine (1), one end (4a) of the thread (4) is contacted by means of a suction nozzle (10) on a surface of a spool (7) and Thread (4) against its regular withdrawal direction (AR) unwound from the spool (7). The thread (4) is sucked into the suction nozzle (10), wherein the coil (7) by means of a reverse rotation drive (8) in the reverse direction (RR) is driven. By a feed movement of a feeder element (9) a thread loop (4b) from the thread (4) is clamped and delivered to a Ansetzorgan (12). The spool (7) is also driven during the tightening of the thread loop (4b) in the reverse direction (RR) and the thread (4) further unwound from the spool (7). A return rotational speed of the coil (7) is adjusted to the feed movement of the feeder element (9). The textile machine (1) has a controller (15) which is designed to operate the reverse rotation drive (8) of the coil (7) accordingly.

Description

The present invention relates to a method for automatic attachment of a thread to a workstation of a textile machine, wherein one end of the thread is picked up by means of a suction nozzle on a surface of a spool and the yarn is unwound from the spool and sucked into the suction nozzle against its regular take-off direction , The coil is driven by means of a drive in the reverse direction. By a feed movement of a feeder organ a thread loop is stretched out of the thread and delivered to a Ansetzorgan. Furthermore, the invention relates to a textile machine with at least one job, with a suction nozzle for finding one end of a thread on a surface of a spool and for sucking the thread, with a drive for driving the spool and unwinding the thread from the spool against its regular take-off direction. Furthermore, the textile machine has a Ansetzorgan for automatically attaching the thread and a feeder element for mounting a thread loop from the thread and for feeding the thread loop on the Ansetzorgan. Furthermore, the textile machine has a control.

In textile machines such as spinning machines or winders, in which continuously produces a thread or is supplied by a delivery reel and is wound on a package, it is necessary after interruptions in the production process to re-set the thread. Such interruptions can be done for example by a thread break, by a cleaner cut or a shutdown of the individual job or the entire textile machine. For automatic reinstatement of such a thread, various methods or various textile machines with attachment devices have become known in the prior art. To reinstate the thread, it is necessary to use a suction nozzle to search the thread on a surface of the coil. The suction nozzle is for this purpose subjected to negative pressure. In order to facilitate finding and sucking the thread end, while the coil is driven in the reverse direction. Once the thread has been found and a corresponding length of thread has been sucked into the suction nozzle, the drive for the reverse rotation of the coil is turned off. At the same time the suction nozzle is a distance away from the bobbin surface, so that the sucked thread is now stretched between the suction nozzle and the coil. Subsequently, a feeder element is delivered to the sucked-in thread which grasps the thread and forms a thread loop therefrom by being pivoted from the thread receiving position in the area of the reel into a thread transfer position in the region of the piecing element. Such a textile machine or such a method is for example in the DE 35 15 765 C2 shown. It has been found in such devices or such a method difficult to maintain a constant thread tension when mounting the thread loop. However, this is desirable in order to avoid further cracks of the thread and the formation of twists in the sucked thread piece.

Object of the present invention is therefore to propose a method for automatically applying a thread, by means of which the thread tension can be kept substantially constant during formation of the thread loop. Furthermore, a corresponding textile machine to be proposed.

The object is solved with the features of the independent claims.

In a method for automatically applying a thread to a workstation of a textile machine, in particular for piecing a thread at a spinning position of a spinning machine, one end of the thread is picked up by means of a suction nozzle on a surface of a spool and the thread is unwound from the spool against its regular take-off direction and sucked into the suction nozzle. The coil is driven by means of a drive in the reverse direction. By a feed movement of a Zubringerorgans a thread loop is stretched out of the thread and an Ansetzorgan, in particular a job-own Ansetzorgan, delivered.

It is now envisaged that the spool is also driven during the tightening of the thread loop in the reverse direction and the thread is unwound from the spool. In this case, a return rotational speed of the coil is adjusted to the feed movement of the feeder element. Due to the fact that the spool is also driven during the tightening of the thread loop in the reverse direction, the thread length required for the formation of the thread loop is no longer withdrawn from the suction nozzle as in the prior art, but the required thread length is returned directly from the spool , Since the speed of the coil is tuned to the feed movement of the feeder element, it is possible to keep the thread tension of the sucked thread also largely constant. The formation of twists in the sucked piece of thread can thereby be avoided as well as further thread breaks. In addition, the thread length required for the preparation can be maintained more accurately at a constant yarn tension. In addition, it is no longer necessary to unwind a larger amount of the thread from the first coil and suck it into the suction nozzle, which also means a corresponding amount of time. Rather, immediately after the detection of the thread end through the suction nozzle, the thread can be taken up by the feeder element and the thread loop can be opened.

The drive of the coil is preferably first stopped after the suction of the thread end and only set in motion together with the feeder again. The vote on the movement of the feeder element is thereby particularly easy.

A suitable for carrying out the method textile machine with at least one job has a suction nozzle for finding one end of a thread on a surface of a coil and for sucking the thread, a drive for driving the coil and unwinding of the thread from the spool against its regular take-off direction and a piecing device for automatic attachment of the thread. Furthermore, the textile machine has a feeder element for clamping a thread loop out of the thread and for feeding the thread loop to the piecing element and a controller. The controller is designed to operate the drive of the coil according to the method described above.

The textile machine can be designed as a spinning machine or as a winder. Accordingly, in the context of the present invention, the application of a thread means both piecing on a spinning machine and splicing on a winding machine.

In the method, it is also advantageous if the return rotational speed of the bobbin is tuned such that a yarn length returned by the bobbin is always synchronous with a yarn length required to form the yarn loop. In other words, during the tightening of the thread loop, the current return speed of the thread from the bobbin is always the same as the current withdrawal speed of the thread through the thread catcher. In this way it is also possible to take into account a temporally different need for additional thread length during the feed movement of the feeder element. Such, temporally different, current need for further stretching of the thread loop is required for example due to the pivoting movement of a pivotable feeder element and due to the acceleration or deceleration of the feeder element.

In a textile machine, it is also advantageous if at least the drive for turning back the coil and the feeder element on the at least a workstation are arranged. It is particularly advantageous if the job is designed as a so-called self-sufficient job and in addition to the drive and the feeder organ additionally has a workstation's own suction nozzle and a workstation's own Ansetzorgan. The vote of the return speed of the coil on the movement of the feeder element is thus possible in a particularly simple manner.

It is also advantageous if the feed movement of the feeder element is a pivoting movement. The feeder element can thereby be structurally simple and arranged to save space at the workplace.

According to a first embodiment of the method, it is advantageous if the return rotational speed of the bobbin is tuned such that a thread length actually fed back from the bobbin is always smaller than a thread length currently required for forming the thread loop at any point in time when the bobbin is being reversed. In other words, during the tightening of the thread loop, the return speed of the thread from the bobbin is always smaller than the withdrawal speed of the thread through the thread catcher. As a result, a tensile force is exerted on the thread, which is greater than the thread holding force on the spool. It is thereby ensured that the thread is not hooked on the surface of the coil due to its hairiness, but can be unrolled neatly.

It may be advantageous to perform the size of the yarn tension during rewinding or the ratio of the return rotational speed of the coil to the withdrawal speed of the thread through the thread catcher depending on the nature of the currently spun yarn. The different properties of the different yarns can be taken into account.

Furthermore, it is advantageous if the yarn tension is measured during the reverse rotation of the coil. For example, the crossing a maximum tensile force can be prevented by the piecing process is stopped, or it can be set the return speed of the coil and / or the withdrawal speed of the thread so that a maximum yarn tension is not exceeded and / or a minimum yarn tension is not exceeded.

According to another embodiment of the method, however, the return rotational speed of the coil is tuned such that at any time of the rewinding of the spool currently fed back from the spool thread length is always greater than a thread length currently required for forming the thread loop. In this way it can be ensured that the thread length required for the formation of the thread loop is only returned from the spool and is not partially or completely pulled out of the suction nozzle again.

In order to tune the return rotational speed of the spool to the feed movement of the feeder element, it is also advantageous if a speed profile for the reverse drive is specified and the reverse drive is driven during the feed movement of the feeder according to the predetermined speed profile. In the speed profile for the reverse rotation drive can at any time of tightening the thread loop different need for nachzuliefernder thread length, bill be taken and the yarn tension in the sucked yarn end are kept substantially constant.

Additionally or alternatively, however, it is also possible to measure a thread tensile force of the thread during the feed movement of the feeder element. The reverse rotation drive is driven according to the measured yarn tension. The return rotational speed of the bobbin can, for example, always be regulated in such a way that a certain, predefinable yarn tension is not exceeded or a specific, specifiable yarn tension not fallen below. Also in conjunction with a speed profile for the reverse rotation drive can be improved by an additional measurement of the yarn tension of the sucked yarn compliance with a constant yarn tension.

The workstation has a corresponding measuring device for measuring the thread tension of the sucked thread. This can be arranged, for example, in the region of the coil itself or else on or in the suction nozzle.

Figur 1

eine Arbeitsstelle einer Textilmaschine in einer schematischen Schnittdarstellung während des regulären Betriebs,

Figur 2

die Arbeitsstelle nach einer Unterbrechung des regulären Betriebs, wobei ein Faden in eine Saugdüse eingesaugt wurde,

Figur 3

die Arbeitsstelle der Textilmaschine in einer weiteren Situation, in welcher gerade eine Fadenschlaufe gebildet wird, sowie

Figur 4

die Arbeitsstelle der Textilmaschine in einer Situation, in welcher die Bildung der Fadenschlaufe gerade beendet wird und der Faden einem Ansetzvorgang zugestellt wird.

Further advantages of the invention will be described with reference to the embodiments illustrated below. Show it:

FIG. 1

a workplace of a textile machine in a schematic sectional view during normal operation,

FIG. 2

the workplace after interruption of normal operation, with a thread sucked into a suction nozzle,

FIG. 3

the workstation of the textile machine in a further situation in which just a thread loop is formed, as well as

FIG. 4

the workstation of the textile machine in a situation in which the formation of the thread loop is just finished and the thread is delivered to a piecing process.

FIG. 1 shows a schematic sectional view of a job 2 a textile machine 1. The job 2 has in the usual way a spinning device 3, by means of which a thread 4 is produced. The yarn 4 is withdrawn by means of a take-off device consisting of two take-off rolls 5 from the spinning device 3 and fed to a winding device 6, where it is wound by means of a yarn guide 11 on a bobbin 7. The winding device 6 includes for this purpose a drive 8, which drives the coil in its regular direction of rotation DR (see arrow) during the regular operation shown here. Like the direction of rotation DR, furthermore, the regular withdrawal direction AR of the thread 4 is indicated by an arrow. Between the take-off rollers 5 and the winding device 6, the thread 4 can go through even more facilities. For example, in the present case, a paraffining device 13 is provided.

Notwithstanding the representation shown here, in which the textile machine 1 is designed as a spinning machine, it is of course also possible that the textile machine 1 is a winder. In this case, the job 2 no spinning device 3, but only a delivery reel, from which the thread 4 is withdrawn and then as described the winder 6 is supplied.

The job 2 of the presently shown textile machine 1 is further designed as a so-called autarkic workstation 2 and has a working owning Ansetzorgan 12, a workstation own suction nozzle 10 and a workstation own feeder organ 9, by means of which after an interruption of production of the thread 4 received by the suction nozzle 10 and the workstation own Ansetzorgan 12 in the form of a thread loop 4b (s. Fig. 3 and 4 ) can be submitted. The suction nozzle 10 is connected in a conventional manner to a vacuum channel 14 and can be acted upon by this with negative pressure to after an interruption of the spinning process or production accumulated on the coil 7 thread end 4a (see Figure two) on the surface of the coil 7 to visit.

As shown, the suction nozzle 10 is fixedly arranged at the workstation 2. The yarn 4 therefore passes through the suction nozzle 10 during production, into which it enters at an opening 16 and which leaves it again through the mouth 19. Alternatively, it would be However, it is also conceivable to let the thread run in a known manner outside the suction nozzle 10 and then to arrange the suction nozzle 10 movably at the workstation 2 in order to be able to deliver it to the yarn end 4 a of the bobbin 7.

The feeder element 9 is provided for receiving the thread 4 with a thread holder 17 and pivotally arranged at the workstation 2, as symbolized by the arrow and the dashed position of the feeder element 9. Finally, the textile machine 1 also has a controller 15, by means of which at least the drive 8 and the feeder element 9 can be controlled. The controller 15 can be provided both as a workstation-specific controller 15 and as a central controller 15 of the textile machine 1. It is also possible that the controller 15 is provided as a group control for several jobs 2.

Now that the textile machine 1 and the job 2 of the textile machine 1 has been described with their facilities, is based on the Figures 2-4 the further method for applying and forming a thread loop 4b explained. In doing so, for features that are compared to those in FIG. 1 illustrated embodiment are identical or at least comparable, the same reference numerals used. Unless these are explained in detail again, their design and mode of action corresponds to the design and mode of action of the features already described above.

FIG. 2 shows the job 2 of the textile machine 1 in a situation in which the production has been interrupted and an end 4a of the thread 4 accumulated on the spool 7. The thread end 4a must therefore be visited on the surface of the coil 7, to which the suction nozzle 10 is subjected to negative pressure and the coil 7 by the drive 8 in the reverse direction RR (see arrow above the coil 7) is driven. Previously, the feeder element 9 was already from its rest position or attachment position, which in FIG. 1 is shown in its thread receiving position, which in FIG. 2 is shown, pivoted. The feeder element 9 thus extends with its thread holder 17 in the cross section of the suction nozzle 10, so that the thread 4 is not only sucked into the suction nozzle 10, but also enters the thread holder 17 of the feeder element 9. In the in FIG. 2 As shown, the thread runs correspondingly from the spool 7 via the mouth 19 of the suction nozzle 10 through the yarn holder 17 of the feeder element 9 and is held by the induced draft, which prevails within the suction nozzle 10. The thread end 4a is already sucked into the suction nozzle 10.

FIG. 3 shows the job 2 of the textile machine 1 in another situation in which the formation of the thread loop 4b has just started from the sucked end 4a of the thread 4. The feeder element 9 with the recorded in the thread holder 17 thread 4 is this from the in FIG. 2 shown thread receiving position pivoted back towards the piecing position, as symbolized by the arrow. As can be seen from the illustration, an additional thread length FL, which is illustrated here by a dotted line, is required for forming the thread loop 4b. This is now unlike in the prior art not pulled out of the suction nozzle 10, but provided by the winding device 6 is available. The coil 7 is for this purpose driven by the drive 8 in the reverse direction RR (see arrow above the coil 7). It must therefore be sucked into the suction nozzle 10, which is just sufficient to hold the yarn end 4a by the pressure prevailing in the suction nozzle 10 negative pressure compared to the prior art, only a smaller length of the thread end 4a.

In particular, however, it is possible by the return of the thread loop FL required for the formation of the thread loop 4b from the spool 7 to provide the thread length FL currently required at each moment of the feed movement of the feeder element 9. The return speed For this purpose, the coil 7 is matched to the movement of the feeder element 9 in such a way that the thread length returned by the reel 7 always behaves synchronously with the thread length FL required to form the thread loop 4b. In other words, at no time does an excess thread length arise, which would eventually twist and interfere with the subsequent piecing process. Likewise, at no time does an increased thread tension, which would otherwise lead to a spring-back of the thread end 4a prepared for piecing or a shortened thread end 4a, result from the synchronous adjustment of the supplied thread length to the currently required thread length FL. The risk of renewed thread breaks can be reduced thereby.

However, it can also be advantageous to always return a little less thread length from the spool than is currently needed to form the thread loop. This not only does not create any excess thread length that could twist or could lead to so-called. Backloops, but the thread can always be kept under tension during the Rückuckspens. The yarn tension should be greater than the adhesive force of the thread on the spool. The thread can not get caught on the spool, but is always handled clean and returned.

The FIG. 4 finally shows the job 2 of the textile machine 1 in a further situation in which the formation of the thread loop 4b is almost complete and the thread loop 4b is transferred to the Ansetzorgan 12 for preparation. The feeder element 9 is this again in the piecing position, which also in FIG. 1 shown is spent. Furthermore, FIG. 4 again shows the thread length FL accumulated up to this time and required to form the thread loop 4b.

By the Ansetzorgan 12 then the thread loop 4b is separated in a conventional manner, so that a new thread end 4a is formed, which prepares for piecing or for piecing and in the spinning device 3 is returned, where it is spun again. If the textile machine 1 is designed as a winding machine, the newly formed thread end 4a is delivered according to a splicer, where it is connected to another thread end 4a, which comes from the drainage coil ago, again. The now separated, original thread end 4a is then disposed of by the suction nozzle 10 and the vacuum channel 14.

In order to tune the return rotational speed of the bobbin 7 to the feed movement of the feeder element 9, it is possible, for example, to predefine the drive 8 with a speed profile which it departs during the feed movement of the feeder element 9. As a result, acceleration and braking times as well as a non-uniform movement of the feeder element 9 with respect to the thread length FL can be taken into account and correspondingly compensated, and thus the thread tension can be kept substantially constant.

However, particularly accurate matching and delivery of the thread length returned by the bobbin 7 in synchronism with the thread length FL needed to form the thread loop 4b is possible when yarn tension in the sucked thread 4 is measured and the return rotational speed of the drive 8 is controlled such that the Yarn tension is largely constant. For this purpose, at the workstation 2, in this case at the suction nozzle 10, a measuring device 18 is provided (see Figures 3 and 4 ), over which the thread 4 is guided during the formation of the thread loop 4b, so that the tensile force can be measured. The measuring device 18 is also connected to the controller 15 to control or regulate the return rotational speed of the coil 7 signal transmitting. The measurement of the yarn tension can be provided in addition to the control of the drive 8 according to a speed profile to improve the accuracy of the vote of the return rotational speed on the feed movement of the feeder element 9. But it is also possible, the return speed of the drive 8 only according to the thread tension of the thread 4 to regulate.

The present invention is not limited to the illustrated and described embodiments. Thus, in the present case, the method has been described on a textile machine 1 having self-sufficiently trained workstations 2 with at least one workstation's own drive 8 and a workstation's own feeder element 9. In such a textile machine 1, the described method can be used particularly advantageously. However, it is also possible that the drive 8 and the feeder element 9 are arranged on a movable maintenance device of the textile machine 1. Further modifications and combinations within the scope of the claims are possible as well as a combination of features, even if they are shown and described in different embodiments.

LIST OF REFERENCE NUMBERS

1

textile machine

2

place of work

3

spinning device

4

thread

4a

End of the thread

4b

thread loop

5

off rolls

6

spooling device

7

Kitchen sink

8th

Drive the coil

9

Shuttle organ

10

suction nozzle

11

thread guides

12

Ansetzorgan

13

waxing

14

Vacuum channel

15

control

16

Opening of the suction nozzle

17

thread holder

18

measuring device

19

muzzle

AR

withdrawal direction

DR

regular direction of rotation

RR

Reversing direction

FL

Required thread length to form the thread loop

Claims (10)

Method for automatic application of a thread (4) at a workstation (2) of a textile machine (1), in which one end (4a) of the thread (4) is picked up by means of a suction nozzle (10) on a surface of a spool (7) and the thread (4) is unwound from the spool (7) against its regular withdrawal direction (AR) and sucked into the suction nozzle (10), the spool (7) being driven in the reverse direction (RR) by means of a drive (8), and in which by a feed movement of a feeder element (9) a thread loop (4b) is stretched out of the thread (4) and a Ansetzorgan (12) is delivered, characterized in that the coil (7) even during the tightening of the thread loop (4b) is driven in the reverse direction (RR) and the thread (4) is unwound from the spool (7), wherein a return rotational speed of the coil (7) is adjusted to the feed movement of the feeder element (9). Method according to the preceding claim, characterized in that the return rotational speed of the spool (7) is tuned such that a thread length returned by the spool (7) is provided in synchronism with a thread length (FL) required to form the thread loop (4b). A method according to claim 1, characterized in that the return rotational speed of the spool (7) is tuned such that at each time of the rewinding of the spool, a thread currently returned from the spool (7) is always smaller than one for forming the thread loop (4b). Currently required thread length (FL). A method according to claim 1, characterized in that the return rotational speed of the coil (7) is tuned such that to each Timing of the reverse rotation of the reel currently fed back from the spool (7) thread length is always greater than one to form the thread loop (4b) currently required thread length (FL). Method according to one of the preceding claims, characterized in that a speed profile for the drive (8) is specified and the drive (8) during the feed movement of the feeder element (9) is driven in accordance with the predetermined speed profile. Method according to one of the preceding claims, characterized in that during the feed movement a yarn tension of the yarn (4) is measured and preferably the reverse rotation drive (8) is driven in accordance with the measured yarn tension. Textile machine (1), in particular a spinning or winding machine, with at least one workstation (2), with a suction nozzle (10) for finding one end (4a) of a thread (4) on a surface of a spool (7) and for sucking the thread (4), with a drive (8) for driving the spool (7) and unwinding the thread (4) from the spool (7) against its regular withdrawal direction (AR), with a piecing element (12) for automatic attachment of the thread ( 4), with a feeder element (9) for mounting a thread loop (4b) from the thread (4) and for feeding the thread loop (4b) to the piecing element (12) and to a controller (15), characterized in that the controller (15) is adapted to operate the drive (8) of the coil (7) according to at least one of the preceding claims. Textile machine (1) according to the preceding claim, characterized in that at least the drive (8) of the coil (7) and the feeder element (9) are arranged on the at least one workstation (2). Textile machine according to one of the preceding device claims, characterized in that the feed movement of the feeder element (9) is a pivoting movement. Textile machine according to one of the preceding device claims, characterized in that the workstation (2) has a measuring device (18) for measuring a thread tension of the sucked thread (4).

Images