EP0404045B1 - Method of changing bobbins of a textile machine and the machine itself - Google Patents

Description

The invention relates to a method according to the preamble of claim 1 and a textile machine according to the preamble of claim 5.
The method and device are known from DE-OS 21 28 974 (Bag. 805) and DE-PS 33 44 993 (Bag. 1316).

In the known method and the known device, many threads are processed in one work station of the textile machine. Each processing station consists of delivery units, processing equipment and a winding device, which are arranged in a vertical plane. Similar machine parts of the processing stations lying next to each other, such as delivery plants, winding devices, are aligned with one another.

A preferred example of such a textile machine is a false twist crimping machine which is used for crimping smooth synthetic threads and in which each processing point consists in particular of a delivery unit, a heater, a cooling zone, a false twister, a further delivery unit and then a winding device.

In the known method and in the known device, the take-up reels of a plurality of take-up devices lying one above the other in a column are changed synchronously, that is to say they are changed in time.

The object of the invention is to provide such a method and a device in which a cycle change of all take-up spools of a textile machine is possible in a time-saving and flexible manner with simple means.

Such methods for changing the cycle of all winding devices of a textile machine are used in particular when a large number of identical bobbins with exactly the same structure and the same thread length are required. This requirement must be met, for example, for dye bobbins in order to have identical dyeing properties for all dye bobbins, e.g. To achieve ink receptivity, flushability or penetration properties for paint or flushing liquid.

This object is achieved by the features of claims 1 and 5, respectively.

The cycle change takes place according to the invention essentially by synchronously starting the traversing after inserting the empty tubes into the individual winding devices and by synchronously ending the winding travel of all winding devices by synchronously cutting off all the threads.

This ensures that the duration of the winding trip is the same for all winding devices. During the changeover period, the textile machine continues to operate in the crawl gear. For this purpose, the winding speed and the thread conveying speed of all work stations of the textile machine are reduced to creep speed. The thread feed speed is the speed at which the threads run to their winding devices during manufacture and / or processing. Switching on the creeper can be done by a central control of the speed of rotation and thread feed speed can be easily achieved. At creep speed, a sufficiently long operating time is available for the bobbin change and for the laying of the threads on the reserve devices for all winding devices, without stopping the machine. The creep speed is as low as possible, ie just high enough to avoid damage to the thread that leads to thread breakage. Such damage occurs when the thread is at a standstill or when the speed is too slow, in particular if the workstations also contain heating devices for the synthetic threads, in particular in false twist crimping machines. As long as there is no thread breakage, damage to the threads is harmless, since the amount of thread occurring in creeper operation is small and is sucked up as waste or wound up as a bead of waste. The full bobbin tubes can be exchanged for empty bobbin tubes by hand or by automatic doffer operation. From DE 38 25 273 A1 (IP-1592), for example, a multi-digit textile machine is known, in which the bobbin change takes place by doffer operation.

The thread reserve winding is formed on the end region of the empty tube. In addition, a waste winding is also wound up on the end region of the empty tube or on part of the winding spindle. To produce the thread reserve winding and the waste winding, the thread is guided over the so-called reserve device, which contains a suitable thread guide.
The invention allows two different alternatives for applying the thread to the empty tube of the winding device assigned to it and for inserting it into the assigned thread reserve device.
On the one hand, the thread, which runs continuously into the waste device after cutting, can pass between the top thread guide (fixed point) of the traversing device and the waste device into a take-over device, for example a hand-held suction gun, taken over and pulled out into a loop. This means that the thread piece running in from the head thread guide of the suction gun and / or the thread piece running between the suction gun and the waste device are first fed via the reserve device and the empty tube and run back from there into the waste device. In this case, the thread loop placed on the reserve device only has to be severed in the area of the piece of thread between the take-over device (suction gun) and the waste device after the thread has been taken over by the empty tube.

In another variant of the method, the thread is taken from the waste device by means of a take-over device, for example by means of a hand-held suction gun, by holding the suction gun on the thread between the head thread guide of the traversing triangle and the waste device and severing the piece of thread between the suction gun and the waste device. Using the suction gun, the thread can now be placed against the empty tube of the winding device and inserted into the thread reserve device. Then the thread piece running between the empty sleeve and the suction gun must be severed. The cutting can be done for both variants by tearing as well as cutting. The thread inserted into the thread reserve device runs into its empty tube, which rotates slowly in the crawling gear, in essentially a normal plane until the threads of all the winding devices are placed on their empty tube and inserted into their associated reserve devices. The normal planes into which the threads run during thread application lie next to the winding area in which the take-up spools are formed during operation. When all the threads are placed on their empty tubes and placed in their thread reserve devices, the reserve devices are triggered synchronously. This will thread the threads towards the The center of the traversing stroke is conveyed at a specific speed, so that a thread reserve winding is formed in addition to the actual winding area. As soon as the threads have reached the area of the traversing stroke, they are gripped by the self-catching traversing thread guide of the traversing device. As a result, the traversing for all winding devices begins synchronously.

If one wants to ensure that the yarn condition corresponds to the final quality at the start of the traversing, it is proposed (claim 2) that the reserve devices are only released after the operating speed has been reached. If the reserve devices are only released after the operating speed has been reached, this method is particularly suitable in those cases in which the thread is subjected to a temperature treatment at its work site. This ensures that the dwell times of the thread on its heating device correspond to the target time from the beginning to the end of the winding cycle. This is particularly important with false twist texturing machines.

Another method variant results from the characterizing part of claim 3. In this variant of the method, the guidance of all reserve devices is first disengaged synchronously, so that the traversing for all winding devices begins at a lower speed than the operating speed. This is followed by an increase in the speed of rotation of the bobbin tubes with a simultaneous increase in the thread feed speed.

As a result of the traversing beginning before the final operating speed is reached, there is the advantage that the waste winding becomes smaller. In one embodiment, a yarn quality can be achieved with the start of the traversing from approximately 70% of the operating speed, which is not significantly different from the final quality at operating speed.
Another advantage of this process variant is that the operating times are extended for all winding devices located in the same cycle. As a result, there is also a longer time available for doffing the other winding devices. This fact takes into account that the winding devices located in the same cycle are only permitted during the operation of other winding devices in the winding position.

A special feature of the invention is that a simultaneous termination of the winding process for all take-up bobbins takes place by cutting the thread, with it not being necessary to shut down the traversing device. This is achieved in particular in that the threads are guided into the catch area of the waste device during the traversing so that they can be automatically snapped on by the waste device when they are cut.

A method suitable for this is provided by the preferred embodiment according to claim 4.
The corresponding device results from claim 5.

Suitable thread traps, which do not interfere in particular in operation and which are nevertheless operationally reliable, result from claim 6, 7 or 8. The advantage of the embodiment according to claim 8 is that thread traps are easily created by lengthening the suction openings in the circumferential direction catch the changeable thread safely without additional measures. The suction pipe itself serves during operation as a deflection rail or to support the deflection rail, which is within the Traversing triangle lies and the traversing triangle bends in two planes at an angle to each other. The rotatability of the suction tube can also be used to switch the guidance through the thread reserve device on and off (claim 17) and / or to switch the suction effect of the tube on or off again for the bobbin change (claim 10). The use of the suction tube as a waste device offers a particular advantage if there is a common suction tube for horizontally adjacent winding devices, which serves as a common waste device for the horizontally adjacent winding devices and at the same time for actuating the thread traps, the knives and the thread reserve devices of these winding devices.

The suction can be switched off with simple means during the winding cycle. To switch off the suction, the suction pipe is separated from the blower generating the negative pressure by means of a valve blocking the rotation of the suction pipe. Another embodiment provides that an electrical switch for switching off the fan is actuated when the suction pipe is rotated. In order to ensure that the suction is switched on and off synchronously for all take-up devices, the suction openings of the individual take-up devices are arranged on a common pipe surface line, so that the catch areas of the suction openings when the suction pipe is rotated about its longitudinal axis in the direction of rotation of the activation of the suction device also all threads to capture.
After all the threads have been placed on the empty bobbin tubes, rotation of the suction tube in the direction of shutdown ensures that the threads do not pass over the catch areas of the suction openings during the traversing. The suction openings are thus removed from the traversing planes of the threads by the suction tube rotation.

Before cutting off the bobbin, the thread is brought into a precisely defined position for suction, so that the cut thread is always reliably caught even with a low suction tube vacuum.

In this application, “traversing plane” is to be understood as meaning the area that is spanned by the traversing triangle. This area does not have to be in one plane. Depending on the path of the thread guide, it can also be a curved surface. When the thread is deflected e.g. By means of a deflection rail transverse to the thread run between the fixed point of the traversing and the traversing thread guide, the traversing triangle consists of two planes at an angle to one another, which are bent along the deflection line.

Preferred features result from the characterizing features of claims 9 to 15, which have proven to be advantageous for the synchronous cutting of the threads. It is essential that the knives are brought into the thread course only at the end of the winding trip. Active knives, e.g. Scissors are used. However, preference is given to passive knives - these are fixed blades - over which the thread is drawn under longitudinal tension. When using scissor-like knives, it is essential that all knives are actuated synchronously, which can be achieved mechanically by a corresponding gear connection together with a common drive or electromagnetically by simultaneously applying a current pulse.

In contrast, the designs according to claims 9 to 15 have the advantage that the reciprocating traversing movement of the thread is used for cutting. As a result of the traversing movement, the thread is guided and cut over a knife blade pointing transversely to the thread running direction yourself from (claim 9). The knife blade can lie obliquely to the thread running direction (claim 12). In this case, it forms an angle with the center line of the traversing triangle which is not 90 ° and preferably points toward the take-up spool with the end which has not yet overrun during the traversing movement.

The knife holders are preferably connected to the rotatable suction tube (claim 10), so that no further transmission elements have to be provided for operating the knives.

In the preferred embodiment according to claim 11, there is the advantage that the optimal parameters, in particular the overflow angle of the knife, need only be set for the thread coming from one of the two traversing directions in order to reliably cut the thread. The thread, coming from one traversing direction, is lifted over the knife holder by crossing the overflow edge and is inevitably changed into the slit for cutting off during the return movement. The knife holder with the knife is preferably attached in such a way that only the thread moved outward from the center of the traversing stroke comes into contact with the knife. This ensures that the thread is always under sufficient thread tension. It is also possible to use a wavy, ground knife edge.

It is important for the quality of the bobbin that the thread end is easy to find. For this reason, a thread cut is desired that lies in one plane, if possible in a plane perpendicular to the thread axis. In particular, damage to the individual filaments, which also leads to confusion of the individual filaments, must be avoided. For this purpose, it is further proposed (claim 12) to arrange the knife in one plane so that it ends the cutting edge is closer to the winding tube than at the beginning. This ensures that the relative speed of the thread in the direction transverse to the knife edge is small and ideally zero. As a result, the relative movement of the thread is limited to a movement in the knife direction, that is to say a movement which, based on experience, leads to a clean cut in a parting plane. To optimize the cutting forces, the knife can furthermore be provided such that its height can be adjusted such that its inclination to the traversing plane can be changed. As a result, the cutting effect of the knife can be improved even further, since the inclination brings about an additional thread tightening during the synchronous cutting process for all threads. The direction in which the inclination should take place also depends, among other things, on the arrangement of the knife edge in the slot. If necessary, the optimal inclination must be determined by experiment. However, it must be set so that the thread experiences an increase in thread tension when it is moved over the knife edge.

A further improvement in the cutting effect can be achieved by the features of claims 14 and 15. The features of claim 14 result in a further parameter in the optimized setting of the knife edge. The blade plane should expediently be set so that the angle between the running direction of the incoming thread from the cutting edge and the blade plane is greater than 90 °. Due to the inclination of the knife plane towards the incoming thread, the component of the direction of the thread running in the direction of the bobbin also contributes to the self-locking tightening of the thread during cutting.

From the features of claim 15 results in a further training with the advantage that there is a further tightening of the thread. The thread is hung in the wedge-shaped slot. The knife edge runs first above the two leading edges and then crosses them diagonally and then remains below the leading edges. There is such a large lateral distance between the knife blade and the guide edges that the thread is not pinched. When moving in, the thread is pulled by the knife edge during its transverse movement under the leading edges and thus additionally tightened. By combining the measure according to claims 11, 12 and 15, the cutting process of the thread can be designed so that it corresponds to the cutting of a thread in the static state, that is, by hand. This results in a clean cut.

An embodiment for synchronously releasing the guidance of the reserve devices results from claim 17.

Switching on the creeper initially means that without changing the gear ratios, the rotational speeds of all delivery mechanisms and the winding device are reduced in the same ratio. It is initially not taken into account that putting the traversing out of operation results in a reduction in the actual winding speed, which is geometrically composed of the circumferential speed of the spool and the traversing speed. In order to achieve a thread tightening, the speed of rotation of the winding spindle with the empty tube stretched thereon can be controlled independently in the sense of an increase independently of the speed of rotation of the delivery mechanisms in the crawling gear. This offers the advantage of a volume-saving, tightly wound waste and thread reserve winding. The method according to claim 18 lends itself particularly to threads which are to be wound up under a relatively low thread tension. The increase in the rotational speed of the winding spindle is expediently coupled with the rotational movement of the suction tube.

The invention is explained below with reference to the figures.

Fig. 1, 2

eine Textilmaschine (teilweise) in Seitenansicht;

Fig. 3, 4

die Aufwickeleinrichtung mit einem vorgeordneten Saugrohr im Schnitt;

Fig. 5

die Ansicht einer Aufspuleinrichtung;

Fig. 6, 7

das Ventil eines Saugrohres;

Fig. 8, 9

eine Schneideinrichtung zum Kappen des Fadens.

Show it:

1, 2

a textile machine (partially) in side view;

3, 4

the winding device with an upstream suction tube in section;

Fig. 5

the view of a winding device;

6, 7

the valve of a suction pipe;

8, 9

a cutting device for cutting the thread.

Figures 1 and 2 show the textile machine 1 in a side view. The further FIGS. 3 to 9 relate to details of the device and the method. 5 shows the perspective view of a winding device 2. In this illustration, the traversing drive and the drive roller required for the spool drive are not shown. The following description initially refers to all figures. Special features, deviations and differences are then emphasized and in the description of the process to be carried out.

In Figures 1 and 2 of the textile machine only the delivery mechanism 13a and the subsequent winding devices are shown. In this regard, it should be noted that the three threads 8 are manufactured or processed in workplaces located next to one another and are delivered by three supply mechanisms 13a lying one behind the other. However, the winding devices 2 for these three threads lie one above the other in a column which covers the three work stations in the longitudinal direction of the machine. The reason for this is that the division of the work stations is considerably smaller (approx. 1/3) than the division of the winding devices 2 which is predetermined by the coil length.

As already mentioned, the machine has a large number of groups of three winding devices 2 arranged vertically one above the other. The picture shows a group with three winding devices which are attached to a machine frame 3. Each winding has in particular a drive roller 4 and a rotatably mounted winding tube 20. The winding tube 20 is supported at the end of one of two parallel swivel arms 6 in such a way that it can pivot away from the drive roller 4 as the spool diameter increases.

As shown in FIG. 5, the winding spindle for the rotatable clamping of the winding tube is formed by two clamping plates 5, which are rotatably mounted in alignment with one another on the free ends of the swivel arms 6. The clamping plate can - as can not be seen - perform a resilient movement inwards so that they clamp the empty sleeve 20 between them. The traversing device 10 is arranged upstream of the winding. FIG. 5 shows that the traversing device has, in particular, a reciprocating thread guide 11, which can be driven by a reverse thread shaft, not shown. The thread guide can be moved back and forth over a certain length 30. This length 30 determines the length of the take-up reel to be produced and is also referred to in this application as a traverse stroke or as a winding length. Through the traversing movement, the thread describes a traversing triangle during winding, the tip of which is the top thread guide = fixed point 18 determined by a thread guide and the base of which is the traversing stroke 30 of the traversing thread guide 11. Guide devices 7 for the incoming threads 8 are located on the side of the winding devices facing the operating side.
Between each guide device 7 and the associated winding point 2 is the traversing device 10, which traverses the thread for winding transversely to its running direction. To reach all rewinders, use a conductor 9 that can be moved along the machine front.

Each guide device contains a suction tube 14 which is rotatably mounted about its longitudinal axis and extends over the length of the machine. The suction pipe carries a guide arm 15 facing the winding device, which is firmly connected to the suction pipe and is therefore also pivoted when the suction pipe rotates. The guide arm carries a thread guide 16 and serves as a thread reserve device, which will be discussed later.

The guide 16 on the guide arm 15 guides the thread 8 outside the traversing area to the empty sleeve 20. The guide device 7 furthermore contains a bar 17 which is located in the thread path of the traversing triangle and is fastened to the suction tube. This bar is arranged between the fixed point 18 and the movement path 30 of the traversing thread guide 10 and parallel to it and serves as a deflection rail for the thread coming from below. The fixed point 18 is formed by a fixed thread eyelet and also referred to in this application as a head thread guide.

The suction pipe 14 extends over a plurality of winding devices 2 which are arranged horizontally next to one another on one floor, only one of which is shown. In the area of each traversing triangle, the suction pipe has a suction opening (radial jacket opening 27). The deflection rail 17 has a slot 29 lying radially above the jacket opening in the tube longitudinal region of each suction opening 27. Each slot is so deep that it surrounds its suction opening 27 as a recess 28 at a distance. This slot 29 serves as a thread trap. It has the task, when swiveling into the traversing plane, to catch the thread that is guided back and forth by the traversing movement on the deflection rail 17 in the recess and to guide it independently of any further traversing movement in the catching region of the suction opening 27. The catch area of the suction opening must therefore be at least as large as the area of the recess 28 in the deflection rail.

Because of the further details of the device shown as an exemplary embodiment and its parts, in particular the knife, reference is made to the following functional description.

Fig. 2 shows the textile machine in operation, i.e. at the beginning of the winding trip. The sleeves or the winding coils formed thereon rest on their respective drive rollers 4 and are driven in rotation by the drive rollers.

Since the winding travel of all threads - as will be explained later - started at the same time and all threads are delivered at the same speed and spooled at the same speed, all the bobbins are full at the same time. The spool is now changed.

• 1. Fangen der Fäden im Saugbereich der Abfalleinrichtung.
• 2. Kappen der Fäden.
• 3. Auswechseln der vollen Spulen gegen jeweils eine Leerhülse.
• 4. Anlegen der Fäden an die Leerhülse.
• 5. Einlegen der Fäden in die Führung der Fadenreserveeinrichtung und Wickeln eines Abfallwickels.
• 6. Lösen der Führung der Fadenreserveeinrichtung und Wickeln der Fadenreserve.
• 7. Beginn der Spulreise durch Einfangen des Fadens in die Changierung.

The spool change consists of the following phases:

• 1. Catch the threads in the suction area of the waste device.
• 2. Thread capping.
• 3. Replace the full bobbins with an empty tube.
• 4. Place the threads on the empty tube.
• 5. Inserting the threads in the guide of the thread reserve device and winding a waste roll.
• 6. Loosen the guide of the thread reserve device and winding the thread reserve.
• 7. Start of the winding trip by catching the thread in the traversing.

In phases 1 and 2, the delivery speed and winding speed are reduced to a creep speed (operation in the creep speed).

In phases 6 and 7, the speed is increased to the speeds of normal operation.

The following occurs in phase 1: As can be seen from FIGS. 3 to 5, when the suction tube rotates, the guide arm 15 and the knife holder 33 are also pivoted together with the knife 34. Furthermore, by means of a special valve device, which is shown in FIGS. 6, 7 and which will be discussed later, the suction pipe is placed under negative pressure, so that a suction flow is created in the suction openings.

In phase 1, the suction tube is now pivoted so that the suction openings 27 face the thread path and that the slot 29 with the recess 28 penetrates the traversing plane of the traversing triangle. As a result, the thread, which is first guided on the deflection rail 17, falls into the recess 28. The thread now runs in the normal plane and on the suction opening and is here exposed to the suction flow. However, the thread is still guided back and forth by the traversing device between the recess 28 and the traversing device 10.

Phase 2 (cutting the threads): As is particularly clear in FIG. 5, when the suction pipe is pivoted in the direction of the arrow 26, the knife holder 33 with the knife 34 is in the traversing plane and the thread run between the recess 28 and the reciprocating thread guide 10 has been pivoted.

It should be expressly stated that the knife, which is the subject of the following description, can be used not only for the present method for changing the cycle, but also in other areas of thread technology. In the pivoted position, the knife holder 33 and the knife 34 in a knife plane that intersects the traversing plane. The intersection line between the knife plane and the traversing plane has a component that extends parallel to the winding axis. However, the cutting line preferably also has a component which extends perpendicularly thereto. The knife holder has a slot 35 lying in the traversing plane, into which the thread, which is traversed from the left, runs. The slot is therefore open on one side. One of the longitudinal edges of the slot - in FIG. 5 the lower edge of the slot - is formed by the knife edge 36 of the knife. The other longitudinal edge of the slot - ie the upper longitudinal edge in the figure - is formed by two guide edges 51 (FIG. 8). Each of these guide edges 51 lies in a plane which is parallel to the knife plane and is closely adjacent to the knife plane. There is a leading edge on each side of the knife level. In the practical embodiment, the knife holder 33 consists of two side plates 52 which have the slot 35. A knife 34 is placed between the side plates 52 while maintaining a small distance on both sides such that the knife edge 36 projects into the slot 35 and forms its lower edge in such a way that the slot narrows from its opening to its end and that finally the leading edges 51 cover the knife edge 36. The slot thus narrows for the thread that is chucked into it. As a result of the narrowing, the thread is pressed against the knife edge, which increases the thread tension. With regard to the details for the formation of such a knife holder, reference is made to FIGS. 8 and 9.

Fig. 8 shows a section through the knife holder 33 perpendicular to the knife plane approximately on the line VIII in Fig. 5. It can be seen that the knife holder 33 consists of two side plates 52 which are clamped together by a locking screw 36 and thereby Knife blade 34 clamp between them. For precise adjustment of the inclination or inclination of the knife edge 36, the knife can be adjusted after loosening the locking screw 39 and then firmly clamped again by tightening the locking screw 39.

FIG. 9 shows a section through the knife holder 33 approximately in the traversing plane, the line of sight being on line IX according to FIG. 8. It can be seen from these figures that the side plates 52 of the knife holder and the knife blade 34 do not lie flat against one another, but form a distance between them which prevents the thread from jamming. This also prevents the accumulation of thread residues and fluff.

According to Fig. 8, the knife level, i.e. the plane in which the knife blade 34 lies is inclined such that the angle between the knife plane and the traversing plane is not 90 °. This angle is labeled "alpha". The knife plane is thus inclined so that the knife edge 36 points towards the incoming thread. As a result, the angle alpha, which is less than 90 °, is behind the knife plane when viewed in the thread running direction.

According to FIG. 9, the blade of the knife 34 is arranged obliquely to the center line of the traversing triangle 47 when the knife holder, which is fastened to the suction pipe (not shown here), is in the operating position. With respect to the center line of the traversing triangle, the knife 34 is rotated such that the knife edge approaches the winding tube from its beginning at the inlet of the slot 35 to its end. As a result, the angle "beta", which the knife edge forms with the center line of the traversing triangle, is less than 90 ° and greater than 0 ° behind the knife edge when viewed in the running direction of the thread.

A special feature of the embodiment shown is that the knife holder 33 is equipped with only one slot, which points only in one traversing direction. Such an arrangement presupposes that the thread is always chucked into the slot from one direction. For this reason, the knife holder has at its end facing away from the slot an overflow edge 37 which pierces the traversing plane at an angle and points essentially in the traversing direction. If the thread is only changed - as in the picture - from right to left, it runs up the overflow edge and jumps over knife holder 33. During the next traversing stroke from left to right, the thread is then cut into the slot and cut off.

When the knife holder 33 is pivoted into the traversing plane, the following happens:
On the one hand, the suction pipe is subjected to negative pressure, so that an air flow is drawn into each suction opening. At the same time, the deflection rail 17 pierces the traversing plane with the recess 28. Likewise, the overflow edge 37 of the knife holder 33 pierces the traversing plane. Assume that the thread comes from the right at the moment of pivoting, ie from the side of the knife holder facing away from the slot 35. The thread now travels during its traversing movement on the overflow edge 37 via the slot to the other end of the traversing stroke. During its return movement it comes into the slot 35 and at the same time falls into the slot 29 and the recess 28 of the deflection rail 17. The thread is now guided over the suction opening 27 and continues its oscillating movement between the recess 28 and the traversing thread guide 10. The thread comes onto the knife blade 36. Since the knife blade 36 dips to the right under the leading edges 51 of the slot as the Chaniger movement progresses, the thread - as shown in FIG. 8 - becomes zigzag-shaped on the cutting edge 36 tense. Because the knife plane approaches the spool from the opening to the end of the slot (cf. angle beta in FIG. 9), it is achieved that the thread has no relative speed transverse to the knife edge 36. The thread is therefore cut in only one plane. The cutting process is thus very much modeled on the cutting of a thread on a knife edge in the static state. Since, in addition, the knife plane is inclined against the thread running direction (cf. angle alpha in FIG. 8), sufficient thread tension on the knife edge 36 is additionally ensured.
In other words:
As a result of the deflection of the knife in the direction of the bobbin, a self-reinforcing clamping effect of the narrowing slot and thus a safe cutting off of the thread is brought about, since the thread which has been caught is tightened. The inclination or inclination causes an additional thread tensioning during the overflow over the knife edge, since the thread is forcibly lifted up to the cut under the thread pulling force over the traversing plane.

As a result of the traversing movement under self-locking, the thread pulls into the constriction in such a way that a thread point slides along on the knife edge 36. The knife edge penetrates the traversing plane obliquely, so that the thread is further away from the traversing plane while the knife edge is overflowing. It is pulled by the knife edge 36 under the guide edges 51 and additionally tightened. As a result, the wrap angle of the thread on the knife edge 36 increases further, as a result of which the frictional forces between the thread and the looped knife edge continue to increase. This continues until the thread is separated. As a result of the increasing frictional force which the looped knife edge exerts on the thread, the thread pulling force continues to decrease wound thread, which also favors the separation process.
Since the thread coming from the left is also caught by the slot 29 of the recess 28, its cut end is inevitably in the catch area of the suction opening and is consequently sucked off by the suction pipe 14 after being cut off.
Phase 3 now begins: replace the full bobbins with an empty tube.

In Fig. 1 it is shown for the lower two winding devices that after the cap on the full bobbin the continuously tapering thread 12 is guided into the suction tube and suctioned off there. Now the full bobbins can be removed from the bobbin holder and replaced with empty tubes 20. 1 and 5, this replacement process has already been carried out. At the winding-on points at which the exchange of the full bobbin for an empty tube has been carried out, follow now
Phase 4: Applying the threads to the empty tube as well
Phase 5: Insert the threads in the guide of the thread reserve device and put the thread back on the empty tube.

Phase 4 and phase 5 are essentially carried out in the same way. It should be noted that in phases 3, 4, 5 the winding devices are not operated simultaneously.

For the description of phases 4 and 5, reference is made in particular to FIGS. 1, 3 to 5. It should be noted that a lever 15 with a guide 16 is also attached to the suction tube for each winding device, which is guided to the height of the traversing plane when the suction tube rotates. 1, upper winding device, and FIG. 4 show a first, with reference to FIG. 3, a second application method.
1 is the Thread is placed on an empty tube by the operator by means of a takeover device 19.

About the devices:
FIGS. 3 and 4 show a side view of details for taking over the running thread from the suction tube and for applying the thread to the empty tube 20. A suction air flow 21 flows through the suction tube 14. This suction air flow initially conveys the thread coming from the fixed point 18 of the traversing until it is picked up by the take-over device - in all cases a suction gun 22. The takeover device serves to take over the thread, which initially still runs into the suction pipe 14, in order to place it on the reserve device and the empty tube 20. For this purpose, the thread piece running into the suction pipe 14 must be severed for both cases. In both cases, cutting takes place by cutting off. A knife 23 is used to cut the thread, which in the case of FIG. 3 is arranged in the suction tube 14, but in the case of FIG. 4 in the suction gun 22. In both cases the knife is inclined to the thread running in the suction direction. Due to the inclination of the knife to the thread run, the thread can run undamaged over the blade in one direction, the suction direction. In the other direction, however, the thread is gripped by the thread cutting edge 24 and cut off.

In the first method according to FIG. 3, the thread initially running into the suction pipe is taken over by the suction gun 22 and drawn out into a loop. This is done in that the thread between the fixed point, ie head thread guide 18, and the suction tube is first drawn into the suction gun 22 and reverses its direction there by 180 °, whereby a loop 25 is formed. The reversing thread piece is still in the suction opening 27 of the suction tube 14. The other thread end running into the suction gun is now pulled out so far that either both thread strands or only one of the thread strands of loop 25 can be placed on the circumference of the empty tube. For this purpose, at least the thread center running from the fixed point of the traversing into the suction gun is placed in the guide fork 16 attached to the guide arm 15, so that the thread runs outside the traversing area of the traversing device 10 to the empty tube. Then the thread is placed on the circumference of the empty tube. The empty tube grips one or both ends of the loop with a suitable catch slot and then winds the thread still running outside the traversing area into a waste bead 32 (FIG. 5) on the empty tube. The suction force of the gun 22 on the thread loop 25 is greater than the suction force of the suction tube 14. Therefore, the piece of thread between the empty tube and the thread cutting edge 24 of the knife blade in the suction opening 27 is stretched so much at the latest during the gripping by the empty tube that the thread comes out the suction opening 27 is pulled out. It is guided over the knife blade 23 inclined in the suction direction. The thread therefore runs up on the cutting edge 24 when it is pulled out in such a way that the thread is cut at the cutting edge 24.

The alternative application method is shown in FIG. 1 and with reference to FIG. 4. The thread between the head thread guide 18 and the suction opening 27 of the suction tube 14 is caught by a hand-held suction gun 22. For this purpose, the operator holds the suction gun 22 in the vicinity of the thread path and then cuts the thread between the suction gun 22 and the suction opening 27 of the suction tube 14 by hand. Now the free thread end starting in the creeper is gripped by the suction gun 22.

In this case, the thread does not form a loop, but instead runs into the suction tube 22 instead of into the suction tube 14, which in turn is connected to a suitable waste device (not shown). The creation makes a difference 3 from the fact that now the piece of thread running into the suction gun is placed on the catching device, for example the catching slot (not shown) arranged on the circumference of the empty sleeve 20 and at the same time placed in the guide 16. After catching the thread on the empty tube 20, the thread, which still runs towards the suction gun 22, comes under a very high tensile force, so that it is pulled out of the suction gun 22. This means that the thread in the mouth region of the suction gun is cut off from the thread cutting edge 24 as soon as the thread is tightened after being placed on the empty tube. The main difference is therefore that the cutting is now done in the thread suction gun and not in the stationary suction pipe.

The following applies to both alternative application methods: since the guide 16 lies outside the traversing stroke, the waste bead is still formed on the empty tube 20, but outside the traversing stroke and the winding area.

After being gripped by the empty tube (application), the thread first runs over the deflecting rail 17 and through the guide 16 of the empty tube 20 and is wound up there to a waste bead 32 without oscillation.

The state of waste winding according to phase 5 is continued until all threads of the textile machine have been placed on their respective empty tubes. The amount of thread that is deposited as a waste package is small, since the entire textile machine has already been switched into the crawl space after phase 2, the cutting of the threads. To produce a stable waste roll, the speed of rotation of the empty tube can be increased somewhat in relation to the delivery speed of the thread, so that the thread is under a sufficiently high thread tension stands on the bead of waste when the thread runs, although the thread runs in only one normal plane and is not guided back and forth by traversing.

When all threads are placed on an empty tube, phases 6 and 7 follow with
Phase 6: loosening the guide of the thread reserve device and winding the thread reserve and the
Phase 7: Start of the winding trip by catching the thread in the traversing.
Phase 6 is initiated by turning the suction pipe. Phases 6 and 7 are carried out synchronously for all winding devices and work stations. Simultaneously with one of the phases 6 or 7, the speed of the textile machine is increased to the normal operating speed.

When the suction tube is rotated, the guide arm 15 is pivoted in the pivoting direction 26.
As a result of the pivoting of the suction tube into the dotted position, the deflection rail 17, which is located between the fixed point 18 of the traversing and the empty sleeve 20, is raised so far that the thread is lifted out of the guide 16 while the guide 16 is lowered. Since the fixed point 18 of the traversing forms the triangle tip of the traversing triangle, but the guide 16 lies outside the traversing triangle, the thread, after being lifted out of the guiding 18, tends to run towards the center of the traversing triangle.

He is somewhat slowed down by the guide rail 15, which adjoins the guide 16 and which the thread is still touching. In any case, before reaching the traversing stroke 30, the thread forms a few turns on the empty tube, which in the future will serve as a thread reserve winding for connecting the thread ends of two bobbins. As soon as the thread in the Traversing area arrives, it is caught by the thread guide 10 and the traversing begins. The thread guide 10 has side flanks which are inclined to the traversing plane and which form a triangle which penetrates the traversing plane. Therefore, the thread guide 10 catches the thread automatically. Since the suction tube connects the winding devices lying horizontally next to one another and therefore all guides 16 become ineffective at the same time, the traversing consequently begins synchronously for all winding devices lying next to one another.

FIGS. 6 and 7 show detailed drawings for a suction pipe 14 which, by rotating in two directions 26 and 31, can either be connected to the suction line 40 or separated from it. The suction line 40 is connected to a suction pump 41 and opens on the side remote from the pump into a valve housing 42 in which a rotatable plug 43 is arranged. The chick can be rotated via handle 44, for example. The plug projects beyond the valve housing 42 on one side, the projecting part being penetrated by an axial blind bore 45. The suction pipe 14 is placed pressure-tight over the protruding part and can be rotated together with the chick. As can be seen, the jacket opening 27 in the suction pipe 14 is rotated at the same time.

As can be seen from FIG. 7, the plug is provided with a connection opening 46 which connects the suction line 40 to the bore 45 in a certain rotational position. The connection is interrupted in the rotational position shown. However, the connection is fully opened by turning it about 90 ° counterclockwise. In this position, the suction pipe is in the suction position. The jacket openings are arranged in such a way that their catch area in the suction position detects the thread passing by.

Instead of a plug valve for switching off the suction by interrupting the suction line, it is also possible, for example, to use an electrical rotary switch which interrupts the power supply to the suction pump 41 when the suction pipe is rotated.

Claims (18)

1. Method of exchanging the wind-on bobbins of a textile machine
   having a plurality of work stations each for manufacturing and/or processing and for winding on one thread,
   in particular a false twist texturing machine,
   in which each thread at its work station is conveyed via delivery mechanisms and a cross-winding device with a self-catching cross-winding thread guide to a wind-on device with a driven rotatable wind-on bobbin,
   wherein the thread passes over a cross-winding plane upstream of the cross-winding device,
   and wherein a plurality of moving threads, having filled their wind-on bobbins, are simultaneously cut and fed into a waste device, while the full wind-on bobbins are exchanged for empty tubes,
   and wherein the threads are then simultaneously applied onto their respective empty tube and, after separation of the thread end running towards the waste device and after formation of a thread reserve lap and possibly a waste winding, are conveyed back into the cross-winding device and wound on,
   characterized by the combination of the following features:

   1.1 all of the threads are synchronously conveyed into the interception region of the waste device disposed upstream of each cross-winding device;

   1.2 all of the threads are synchronously cut between waste device and cross-winding device;

   1.3 the rotating speed of the wind-on devices and the delivery mechanisms is reduced to creep rate;

   1.4 at each wind-on device the full wind-on bobbin is exchanged for an empty winding tube (empty tube) (bobbin change);

   1.5 each thread is applied onto the empty tube of its associated wind-on device and, in so doing, is inserted into the stationary guide of a thread bunch builder in that either

   1.5.1 the thread running towards the waste device is drawn out to form a loop and a thread strand of the loop is applied onto the empty tube and is inserted into the guide of the thread bunch builder and the thread is severed between empty tube and waste device or

   1.5.2 the thread running towards the waste device is picked up as a thread loop from the waste device by means of a pick-up device, severed between waste device and pick-up device, then by means of the pick-up device applied onto the empty tube and inserted into the guide of the bunch builder and then severed between empty tube and pick-up device;

   1.6 once all of the threads have been applied, the rotating speed of all of the wind-on devices and delivery mechanisms is increased to operating speed;

   1.7 the guides of the thread bunch builders of all of the winding stations are synchronously disengaged in such a way that the threads under their tensile force drift into the region of the cross-winding stroke and are grasped there by the self-catching cross-winding thread guides.
2. Method according to claim 1,
   characterized in that
   the increase in the rotating speed of the wind-on devices and the delivery mechanisms is effected before the guide of the thread bunch builders has been disengaged.
3. Method according to claim 1,
   characterized in that
   the increase in the rotating speed of the wind-on devices and the delivery mechanisms is effected after the guide of the thread bunch builders has been disengaged.
4. Method according to one of claims 1 to 3,
   characterized in that
   in step 1.1 the threads are synchronously captured and conveyed each by means of a thread trap in the interception region of their waste device overlapped by the cross-winding plane and then
   in step 1.2 are cut between the thread trap and the cross-winding device.
5. Textile machine
   having a plurality of work stations each for manufacturing and/or processing one thread,
   in particular a false twist texturing machine,
   in which each thread is supplied via delivery mechanisms and a cross-winding device to its wind-on device with the driven rotatable wind-on bobbin,
   wherein the thread between a head thread guide and the cross-winding device passes over a cross-winding plane, having a waste device, a cutting device, a thread bunch builder
   for effecting the method according to one of the preceding claims,
   characterized in that
   the waste device is a suction tube, in which a partial vacuum may be generated and which extends in front of and parallel to a plurality of cross-winding devices, closely adjacent to the cross-winding planes passed over by the threads, and which has one suction opening for each thread in the region of the cross-winding plane,
   that disposed in the interception region of each suction opening is a thread trap which, for capturing and guiding the thread, is movable into the cross-winding plane,
   and that the thread traps of a plurality of work stations may be synchronously activated.
6. Device according to claim 5,
   characterized in that
   the thread trap is a guide rail parallel to the cross-winding plane, said guide rail having a notch perpendicular to the cross-winding plane in the region of the suction opening and being movable from a position parallel to the cross-winding plane into the cross-winding plane.
7. Device according to claim 6,
   characterized in that
   the suction tube is rotatable between a position of rest and an operating position, in which the suction openings are turned towards the thread run,
   and that the guide rail is connected to the suction tube in such a way that the guide rail, in the position of rest of the suction tube, lies parallel to the cross-winding plane and, on rotation of the suction tube into the operating position, penetrates into the cross-winding plane.
8. Device according to claim 5,
   characterized in that
   the suction tube is rotatable between a position of rest and an operating position, in which the suction openings are turned towards the thread run,
   and that the thread traps are slots extending in a peripheral direction on the outer periphery of the suction tube, said slots emanating from the suction openings and being provided in such a manner that they are insertable into the relevant cross-winding planes through rotation of the suction tube about its longitudinal axis.
9. Device according to one of claims 5 to 8,
   characterized in that,
   for synchronous cutting of all of the threads, a cutter holder with a cutter disposed perpendicular to the thread running direction is inserted at the end of the winding travel into the cross-winding plane of each thread.
10. Device according to claim 9,
    characterized in that
    the cutter holders are fastened to the suction tube,
    and that they are insertable into the cross-winding plane through rotation of the suction tube about its longitudinal axis.
11. Device according to claim 9 or 10,
    characterized in that
    each cutter holder has an overrun edge for the thread cross-wound from the one cross-winding direction, said overrun edge after insertion into the cross-winding plane obliquely penetrating the cross-winding plane,
    and that cutter and cutter holder form a slot, which narrows in a wedge shape and whose opening is directed with its cutting edge towards the thread cross-wound from the other cross-winding direction.
12. Device according to claim 11,
    characterized in that
    the cutter lies in a cutter plane intersecting the axis of the winding tube in such a way that the cutting edge converges with the winding tube from the opening to the end of the slot.
13. Device according to one of claims 9 to 12,
    characterized in that
    the inclination of the cutting edge relative to the cross-winding plane is adjustable.
14. Device according to one of claims 9 to 13,
    characterized in that
    the angle between the cutter plane and the cross-winding plane is adjustable so as to differ from a right angle in such a way that the cutting edge is directed towards the oncoming thread.
15. Device according to one of claims 9 to 14,
    characterized in that
    the cutter holder to form the wedge-like narrowing slot on either side of the cutter plane has guide edges, which extend in planes parallel to the cutter plane and - in side view - intersect the cutting edge forming an acute angle.
16. Device according to one of claims 5 to 15,
    characterized in that
    the air suction during the wind-on operation may be disconnected in that the suction tube is rotatable about its longitudinal axis, preferably in such a way that the moving threads do not pass over the suction openings during the wind-on operation.
17. Device according to one of claims 5 to 16,
    characterized in that
    the thread bunch builders are fastened to the suction tube and may be swivelled into the thread run through rotation of the suction tube.
18. Method according to one of claims 1 to 4,
    characterized in that
    the rotating speed of the wind-on devices is increased during synchronous cutting of the threads in order to tauten the threads.

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