EP3269853B1 - Method for starting a spindle of a two-for-one twister or cabling machine - Google Patents

Description

The invention relates to a method for starting a spindle of a cabling or double-twisting machine at the beginning of a bobbin travel, wherein on an empty package outside the winding a thread reserve is formed, wherein the cabling or double twisting machine has at least one job, each resting on a twisting bobbin for receiving a first supply spool and a rotating, hollow spindle rotor having a spaced from the spindle hollow axis below the bobbin, lateral outlet opening, wherein a withdrawn from a first supply bobbin inner thread is wound by a withdrawn from a second supply spool outer thread and wherein the outer thread through the spindle hollow axis, whose lateral outlet opening and arranged in a thread bobbin surrounding the bobbin pot to a thread guide which merges the two yarn templates in an extension of the spindle axis above the spindle device is guided, and a take-up device with a yarn guide is present, in which the produced twisted yarn is wound onto the package.

Twisting or cording are methods of mechanical yarn finishing to produce certain performance properties in the twine. While in the double-twisting process two or more yarns are twisted together to form a thread, the cabling is a special twinning process in which two threads are twisted together without the individual threads themselves being twisted. The advantage of twisting lies in their higher tensile strength, since the individual filaments always lie exactly in the loading direction.

For the purposes of this application, the term thread is intended to encompass all line-shaped structures, such as yarns, film tapes, tubular and ribbon-like textiles and the like. For the sake of simplicity, the term thread is used synonymously with the possible alternatives in the context of this application.

A cabling machine, for example, usually has a plurality of jobs, which are arranged side by side in the machine longitudinal direction. The Workplaces each comprise a spindle, on which a supply bobbin is plugged, and a slip-on device arranged on the machine frame, which serves to receive a second supply bobbin. The threads are removed from the supply bobbins and held constant by thread brakes in their tension, cabled and wound in a take-up on a twisting bobbin. Basically, when twisting, the more turns the finished thread should have, the lower the run-up speed drops at a given spindle speed.

At the beginning of a new batch must be twisted, that is, in the creel and in the bobbins of the individual jobs new bobbins are positioned. The threads are threaded in accordance with the thread guide members, guided to the take-up unit and attached to one end of an empty sleeve. In this area, a thread reserve is created outside the actual winding zone, which is required for subsequent processes.

During operation of the cabling spindle, the first feed bobbin on the rotating spindle is arranged in a bobbin pot. The bobbin pot and the bobbin itself are, however, secured against rotation. From this first supply spool a so-called inner thread is pulled off axially upwards and guided on its way to the cabling or fusion point with the outer thread through an inner thread brake.

The second supply spool, from which the outer thread is withdrawn, is arranged in a creel. After the outer thread has passed an outer thread brake and possibly a deflection device, it passes from below axially into the hollow spindle and exits from the spindle on a storage disc. To form a thread balloon, the outer thread rotates around the bobbin pot and is guided to the balloon thread guide. At this point, the outer thread wraps around the inner thread, which is why this is also referred to as Kablierpunkt.

JP H01 298 220 A describes to avoid yarn breaks by accelerating winding parts and spindles that the ratio of the speed at the winding parts to the speed of the spindles is smaller than the ratio of the speed in continuous operation.

JP H05 287 620 A discloses for reducing the yarn breakage at the winding start part and at the winding end of the thread, that the rotational speed of the spindle for predetermined periods at the winding start part or at the winding end part of the thread is less than a predetermined speed.

DE 43 15 775 A1 describes a spinning technology favorable start-up and at the same time more stable nominal operation of a textile machine. It should thus be well used the thread material, its quality can be secured, and the efficiency of the drive can be improved.

By the DE 10 2007 043 352 A1 there is disclosed a cabling machine and a method of operating the same. To produce a twisting bobbin of predetermined weight, the first supply bobbin inserted into the bobbin pot is chosen to be half the weight of the twisting bobbin to be made. The second feed bobbin, which is positioned in the creel, is chosen to be at least equal to the total weight of the twisting spool to be produced. This approach reduces operator effort and the number of remainder feed bobbins. It is quite common in practice that all jobs start at the same time and therefore expire at about the same time.

A disadvantage of this method according to the prior art, however, is that it frequently comes to thread breaks during startup of the Kablierspindeln on their operating speed. This occurs more frequently especially when threads are used for twisting, which have a high number of individual filaments and / or friction-sensitive material such as polypropylene or polyester.

Due to machine-length drives for the Kablierspindeln it has an overall negative effect on the efficiency of such cabling machines when thread breakages often occur at jobs.

Based on the aforementioned prior art, the invention is therefore based on the object to reduce the number of yarn breaks during startup.

This object is achieved by the characterizing features of claim 1.

Advantageous embodiments of the invention are the subject of the dependent claims.

To achieve the object is provided according to claim 1, that during the creation of the thread reserve a relation to the production data increased ratio of the emergence speed of the twist against the rotational speed of the spindle rotor is applied.

Due to this procedure, the time that the outer thread touches the bobbin pot until the formation of the thread ballon is reduced. Until the spindle rotor has reached the production speed at the start of the spindle and the outer thread emerges from the spindle rotor sufficiently quickly to be able to form the thread balloon around the bobbin, the outer thread usually touches the bobbin owing to the lower thread speed. A Spülopfberührung is carried out at the start generally at the beginning relatively over a longer distance, the places where the Outer thread also undergoes a deflection, are the most critical, that is, at the top and / or bottom edge of the bobbin, the latter occurs only at the bottom conically retracted bobbins. If necessary, contact with the cabling hood can also occur.

When twisting, there is a direct relationship between the number of rotations that the finished thread should have, and the Auflaufgeschwindigkeit with which the thread is wound onto the package. In this case, the delivery speed must be set lower because the spindle speed can not be increased.

If the ratio of the running speed to the rotating spindle rotor is increased compared to the production conditions, the friction time of the outer thread on the bobbin is reduced. Due to the less long occurring friction load of the outer thread at the respective coil pot edge of the outer thread is less damaged and occur at the start less thread breaks.

This has a particularly advantageous effect on threads, which are made of threads with many individual filaments and / or friction-sensitive material. The more individual filaments are contained in the thread, the larger the surface of the thread relative to a thread section and the more friction occurs. Because the thread reserve is usually wound outside of the actual production area on the package and used in the further processing of the twisting coils to knot in the creel the following twisting coil to the previous, this initial or end of the twisting coils does not flow into the production of the later Processing processes. For this reason, it is harmless if the thread reserve has significantly fewer rotations than the actual twist under production conditions.

Within the scope of the invention, the method according to the invention can be applied both to cabling or double-twisting machines which have a multiplicity of workstations arranged next to one another in the machine longitudinal direction as well as to what are known as single-spindle units. Furthermore, the method according to the invention is both applicable to machine-driven spindles / Reelers as well as spindles / winders, which have a single drive.

As described in claim 2 is advantageously increased the run-up speed during the creation of the thread reserve against the run-up speed under production conditions.

Particularly easily, the ratio of the run-up speed relative to the rotational speed of the spindle rotor can be increased by the thread reserve is wound onto the take-up reel with higher Auflaufgeschwindigkeit while the spindle speed remains constant. While the spindle is accelerated to 100% of the setpoint speed during spindle start, the ramp speed is 100% plus x. After a selectable time, the run-up speed is lowered to 100% setpoint speed.

This reduces the number of rotations by approximately the factor by which the run-up speed is increased.

The stationary spindle or spindle rotor must be accelerated from standstill to production speed. This so-called run-up is performed with a given acceleration. So far, the acceleration and the resulting run-up ramp has been performed identically for different events. That is, regardless of whether a restart of a lot or a restart, for example, after a thread break, was present, the spindle rotor has been accelerated with identical parameters to the operating speed.

By faster acceleration of the spindle rotor and a resulting shortened ramp, the thread balloon of the outer thread around the bobbin is formed so quickly that the friction of the outer thread is reduced at the critical points.

In the following the invention will be explained in more detail by means of an embodiment with reference to the accompanying drawings.

Figur 1

eine schematisch dargestellte Arbeitsstelle einer Kabliermaschine;

Figur 2

ein Diagramm des Verlaufs der Drehungen in Abhängigkeit von der Auflaufgeschwindigkeit des Zwirns;

Figur 3

ein Diagramm des Verlaufs der Hochlauframpe des Spindelrotors in Abhängigkeit der Beschleunigung;

Figur 4

ein Diagramm des Verlaufs der Drehungen während der Erstellung der Fadenreserve.

The drawings show:

FIG. 1

a schematically illustrated workstation of a cabling machine;

FIG. 2

a diagram of the course of the rotations as a function of the emergence speed of the twisted yarn;

FIG. 3

a diagram of the course of the run-up ramp of the spindle rotor in dependence of the acceleration;

FIG. 4

a diagram of the course of the turns during the creation of the thread reserve.

In the FIG. 1 is shown in a schematic view of the structure of a job a cabling. The cabling spindle 2 is mounted on a spindle bank 3. A top feed bobbin 4 is located in the bobbin pot 5 of the cabling spindle 2. The top thread 6 is pulled off the first supply bobbin 4 and guided through a yarn brake 7 arranged in the cabling hood 1. After the thread brake 7, the inner thread 6 leaves the Kablierhaube 1 through a thread guide eyelet 8 and finally passes through a downstream thread guide device, here a balloon thread guide eyelet 9. The balloon thread guide eyelet 9 is fastened by means of a holder 10 on the machine frame only indicated. Instead of the balloon thread guide eye 9, for example, a so-called cord regulator may also be present.

A second feed bobbin 11 is usually mounted on a Aufsteckvorrichtung arranged on the machine frame and shown here only schematically next to the Kablierspindel 2. The withdrawn from the second feed bobbin 11 outer thread 12 passes from below the spindle hollow shaft 13, is deflected in the radial direction and exits at the yarn storage disc 14 radially. The rotary drive of the yarn storage disk 14 via a Spindelwirtel 15 by a drive belt 16th

Escaping from the yarn storage disk 14 and forming a yarn balloon B, the outer thread 12 is guided on the outside of the bobbin 5 up to the balloon yarn guide eyelet 9. Here, the outer thread 12 is looped around the inner thread 6 and the thread 18 produced in this way further wound onto a package 19. That is, in the balloon thread guide eyelet 9 and the compensation system is the Kablierpunkt in the inner thread 6 and outer thread 12 converge and form the twist or cords 18.

Above the Kablierpunktes a trigger device 20 is arranged,. withdrawn by means of the thread 18 and a compensating element, such as a dancer 21, a take-up device 22 is supplied. The take-up device 22 has a drive roller 23 and a drive shaft 19 frictionally driven by the drive roller 23.

FIG. 2 shows the ratio of the actual spindle speed to the production spindle speed and the ratio of the actual run-up speed to the production run-up speed during the start of a spindle 2. While the ordinate scales the ratio, the abscissa represents a time axis. The first time period shows the progression during the preparation of the thread reserve, which is followed by the period of production and both spindle speed and run-up speed reach a constant value.

Reference numeral 26 denotes the ratio of the actual spindle speed to the production spindle speed. The spindle 2 accelerates over a certain period up to the production speed and then remains constant, which corresponds to a ratio of 1. The reference numeral 27 denotes the ratio of the actual run-up speed to the production run-up speed. The run-up speed increases and reaches a value that is above the production run-up speed, in this example, the value corresponds to a ratio of about 1.5. During this increased actual run-up speed, the thread reserve is wound. After a predetermined time, the actual run-up speed is lowered to the production run-up speed and the thread guide pivots with the Thread 18 in the production area to wind it under production conditions.

The FIG. 3 graphically displays the ramp-up ramp of the spindle rotor. The ordinate shows the spindle frequency. The abscissa scales the time in seconds. Reference numeral 24 designates an acceleration, as has hitherto been carried out when starting a cabling spindle 2 at the beginning of a batch or after the restart, for example after a thread break. The spindle rotor takes about 11.7 seconds to reach the operating speed.

In contrast, the reference numeral 25 denotes an acceleration of the spindle rotor at the beginning of a new batch, which in this example is faster by 2 Hz * s -1 compared to the previous acceleration. As a result, the spindle rotor has already ramped up to operating speed after approx. 8.7 seconds and thus approx. 3 seconds faster. The faster the spindle rotor is accelerated to the operating speed, the faster the outer thread 12 forms the yarn balloon B and the less long rubs the outer thread 12 at the lower and / or upper edge of the bobbin. 5

FIG. 4 shows the creation of about 5 meters long reserve of thread before the thread 18 is produced and wound up under production conditions. At the beginning of the winding process, the number of rotations increases to about 80 T * m ^-1 and the thread 18 is wound at a high run-up speed. After approx. 4 meters, the run-up speed drops and the rotations increase to a preset value of 280 T * m ^-1 . After the predetermined rotation and thus the production speed is reached, the yarn guide pivots with the yarn to be wound 18 in the production area of the package 19 and winds the twine 18 under production conditions.

Claims (2)

1. Method for starting a spindle (2) of a cabling or two-for-one twisting machine at the start of a spindle journey, wherein a yarn reserve is formed on an empty take-up package (19) outside of the winding zone, wherein the cabling or two-for-one twisting machine has at least one workstation, each workstation having a spindle pot (5) at rest during the twisting for holding a first feed package (4) and having a rotating, hollow spindle rotor, which has a lateral outlet opening arranged below the spindle pot (5) at a distance from the spindle hollow shaft (13), wherein an outer yarn (12) pulled from a second feed package (11) is wound around an inner yarn (6) pulled from a first feed package (4) and wherein the outer yarn (12) is guided through the spindle hollow shaft (13) and through the lateral outlet opening thereof and in a yarn balloon (B) orbiting the spindle pot (5) to a yarn guide device (9), which is arranged above the spindle (2) in extension of the spindle shaft and which merges the two yarn supplies, and a winding device (22) having a yarn guide is present, in which winding device (22) the produced yarn (18) is wound onto the take-up package (19),
   characterised in that,
   a ratio of the take-up speed of the yarn (18) to the rotation speed of the spindle rotor that is increased in comparison with the production data is used during the creation of the yarn reserve.
2. Method according to claim 1, characterized in that the take-up speed is increased during the creation of the yarn reserve in comparison with the take-up speed under production conditions.

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