EP0018577A1 - Method and device for the automatic take-up of a yarn on to a bobbin - Google Patents

Abstract

1. A method for automatically starting to wind an running thread (4), which is under tensils stress and which is guided via a traversing element (3), on to a spool (2) or sleeve, characterized in that, with no change in the position of the axis of the spool during the winding-on process, the thread is gripped, at a point in time when the traversing device (3) has essentially reached an end position, by a conveying device and is deflected by a movement of the conveying device parallel to the axis of the spool in the direction of the other end position of the traversing element (3) and the thread is deflected beyond this position in such a way that it is gripped by a gripper (9) which revolves around the axis of the spool approximately through the same plane as the front face of the spool, which faces the deflecting device (3), at a rotational speed which is lower than or the same as the speed of the rotation of the spool, and in that after several windings have been placed on the driven empty spool (2) without overlapping the traversing motion is changed in such a way that a second layer is wound on top of the first layer, by means of which the spool (2) itself produces tension in the thread and the thread which hitherto has been drawn off further by the spool (2) to be freshly wound is cut.

Description

The invention relates to a method for automatically winding a thread under tension on a bobbin or sleeve, the application of this method to a multi-position winding unit and a device for carrying out the method.

The product accumulates continuously when spinning textile threads and monofilaments. While the automatic bobbin change is practiced for textile threads with a free bobbin structure, it is prone to errors with monofilaments or is associated with increased operating effort. Winders with a free bobbin structure cannot be used because flanges are required to limit the winding due to the usual parallel winding of monofilaments. Automatic flange coil winders are known, the one Change thread already on a spool. The automatic threading of the first thread at the start of production is not provided there or is not possible. In such a device, for example, the work and empty coils are placed axially next to one another on individually driven pivotable shafts. Under the coils are the two drive motors that drive the coils on the outside of the flange via toothed belts. When changing the bobbin, the traversing thread guide moves over the previous stroke towards the empty bobbin. After a short winding on the empty spool, the wire is cut by a knife that can be extended through the narrow gap between the two abutting flanges of the spools. During this change, the thread is occasionally drawn off the full bobbin; turns can also fall between the two abutting flanges, which makes it impossible to put them on again.

In another device, this error is avoided in that the thread is guided to the flange via a catch ring or a catch disc. However, as with other known devices, large acceleration forces occur during the transition of the wire to the other coil.

The object of the invention is to make the automatic application and winding of a wire under tension on a spool or sleeve safer with little effort. It should be possible to put it on for the first time, as well as an automatic change from a wound to a new spool with a winding unit without interruption and loss of material.

The task is solved procedurally in that the thread under tension is placed by a gripper several times around the spool to be wound without overlaps, then the traversing is changed so that a second layer is wound over the first layer, whereby the spool itself a thread tension is generated and the thread which has previously been drawn further from the reel to be wound is cut. The method can be used in a multi-position winding unit in which the reel to be wound is moved axially parallel next to the full bobbin and the wire is further wound on the almost full bobbin while the first layer is being built on the new bobbin. In terms of the device, the object is achieved in that there is a deflection eyelet which is on the axis of the spool to be wound so far that a thread from the traversing eyelet to the deflecting eyelet is also in the position where the traversing eyelet is furthest away from the deflecting eyelet. does not touch the bobbin flange, that there is a device that transports the thread from the traversing eyelet into the deflecting eyelet, that there is a rotating gripper outside the flange that lies between the traversing eyelet and the deflecting eyelet, the rotational speed of which can be set less than or equal to the spool rotational speed is, the gripper can pick up and carry the wire running from the traversing eyelet to the deflecting eyelet, and that a thread separating device for the thread drawn off from the reel to be wound and corresponding control devices are present.

With the method and the device according to the invention, the running thread is wound without interruption after a bobbin has been fully wound, reliably and reliably on an empty bobbin; then separated from the full spool before it is unwound again. In the same way, automatic starting is possible if, for example, the running thread is first suctioned off and the winding should only be started upon a signal. The thread tension can be kept at the desired tension during the winding process. This ensures a winding. Sudden changes in traction and speed are avoided. While there are often disturbances in known devices with thicker wires because of the thread stiffness, these are not observed in the method according to the invention.

The device requires little effort; e.g. no special catch discs to be attached by hand per change. The arrangement of the device depends on the task. The device can, as in known systems, be integrated into the winding machine and is then present once per thread or can be a separate machine with only one device, which successively changes the thread from the full to the bobbin that has just become free.

The loads on the thread during the deflection can be influenced in a targeted manner, since the speed of the gripper and the speed of transferring the thread from the traversing eye to the deflecting eye can be freely selected. The permissible thread tensions are not exceeded. In known systems, the forces acting on the thread during the changing process can only be influenced to a small extent, since there they are essentially determined by the delivery speed and the thread tension, and. Fluctuations in the exchange are mainly dampened by the änzer yielding _T. During the application phase, speed jumps can be avoided in the device according to the invention, the thread is gripped at low speed and guided around the bobbin.

In known systems, the time for applying the individual turns cannot be influenced. With a delivery speed of 400 m / min and a winding diameter of 100 mm, the time for applying the first turn has been around 0.05 seconds. In the device according to the invention, this time is freely selectable. Depending on the sensitivity of the winding material, times of 0.5 to 3 seconds have proven successful. This significantly reduces the risk of breakage.

Since the thread is not carried along by frictional forces, problems with the formation and wear of the flange surface are eliminated. It is also not possible for individual turns to fall off the flange.

In the case of thin wires, the cutting device can be dispensed with, since a sufficient tearing force can be generated in the piece of thread which connects the old with the new spool. With thick wires (from approx. 0.3 mm diameter with polyamide) this force is no longer sufficient, it must be cut.

• Fig. 1 Fadenlauf bei einer Spulenwechseleinheit vor dem Wechseln auf die neue Spule;
• Fig. 2 Fadenlauf auf der neu zu bewickelnden Spule beim Aufbringen der ersten Windung;
• Fig. 3 Fadenlauf auf der zu bewickelnden Spule zu Beginn der zweiten Lage.

A coil winding device according to the invention is exemplified in the drawing and described in more detail below. Show it

• Fig. 1 thread running in a bobbin changing unit before changing to the new bobbin;
• Fig. 2 thread running on the reel to be wound when applying the first turn;
• Fig. 3 thread running on the spool to be wound at the beginning of the second layer.

At the time of the bobbin change, the full bobbin 1 and the bobbin 2 to be newly wound are arranged next to one another in an axis-parallel manner. They are driven separately and turn in the same direction. The thread guide of the traversing device is only indicated by the traversing eye 3. When changing the spool, the traversing eyelet should be at the end of the traversing path. Since the spool change takes place very quickly, the traversing device generally does not need to be switched off. The thread 4 is under tension due to the winding on the bobbin 1. When changing the tension is kept constant, which is done by a corresponding control of the drive of the coil 1. When a bobbin is first wound up, the thread tension can of course also be applied by a suction gun or another regulated bobbin.

The rotation speed of the reel 2 to be wound is set so that the peripheral speed on the winding diameter with the Lieferge speed approximately coincides. A (not shown) transport device transports the thread from the traversing eyelet 3 to a deflecting hook 5. The deflecting hook 5 is located on the axis of the spool 2 to be wound, on the side of the spool flange 6 from which the traversing eyelet 3 is just the furthest away is. The traversing eye 3 and the deflecting hook 5 are arranged so that the thread run 7, which originally leads directly from the traversing eye to the spool 1, now leads from the traversing eye via the deflecting hook 5 to the spool 1, not through the flange 6 of the reel to be wound is disturbed. The thread path 8 over the deflection hook 5 is shown in broken lines.

Outside the coil between flange 6 and deflection hook 5, a gripping device 9 is provided concentrically with the coil axis. The initial speed of the gripper is adapted to the load capacity of the winding material, since the thread has to withstand an increased stress due to the additional deflection. However, after the first turn has been applied, this additional load ceases because the deflection angle on the gripper then remains constant. To speed up the changing process, the gripper speed can now be increased without putting much greater strain on the material to be wound than in the normal winding process. The tip of the gripper is designed so that it can grip the thread running from the traversing eye 3 to the deflection hook 5 and can guide it around the bobbin 2. The gripper 9 does not touch the flange 6. An additional turn is brought onto the coil 2 per gripper revolution. If the traversing is stopped or the traversing is still moving away from the gripper, it is ensured that the turns on the coil 2 do not cross. Since the thread and bobbin circumferential speeds are matched to one another, the bobbin 2 only acts as a deflection roller. What accumulates on the spool 2 in the time unit runs off again at the other end and continues to be wound up by the full spool 1. The bobbin 2 itself does not exert any tensile force on the thread. If a plurality of turns are applied to the bobbin 2, a second layer is built up on this bobbin, that is to say the thread running up crosses the turns already placed. This is achieved in that the traversing eye 3 is moved towards the flange 6.

Because of the resulting clamping effect, the bobbin 2 now exerts a tensile force on the thread 4. A thread tension is absolutely necessary in order for the clamping action to occur. The spool 2 is already winding, but since the lower first layer is not completely wound, the windings which have not yet been clamped continue to run off the spool 2. As soon as the last (running) turn of the first layer is crossed by the turns of the second layer, a force develops against the running direction on the running thread. With small titers, this leads to the Rule for separating the thread from the full bobbin and a separate cutting device is not necessary. In the case of large titers, on the other hand, cutting must be done before the last winding is reached. If cutting is to be carried out on the standing thread 8 instead of on the running thread, the speed of the gripper must be variable. In this case, the speed of the gripper is quickly increased up to the spool speed of the new spool. The speed of the full bobbin decelerates from the thread in reverse proportion to the hook speed until it comes to a standstill. At the same speed of rotation of the new coil and the gripper, each turn that runs from the coil 2 is put back on directly by the gripper. This means that the thread between the hook and the full bobbin is at rest and can be cut. However, the cut must also be made here before the last winding winding overflows, since otherwise the thread either breaks, the system brakes or is wound onto the new bobbin in the opposite direction of the running thread.

2 shows another perspective view of the thread path and the reel 2 to be wound in a loop. The path of the tip of the gripper 9 is shown in dashed lines. The reference numerals are the same as in FIG. 1.

In Fig. 3, the first layer is constructed with 4 turns on the coil 2, and the cross-over begins to build up the second layer. The eyelet of the traversing device is moved towards the flange 6. The resulting thread inlet 11 is shown in broken lines in FIG. 3. For the automatic winding according to FIGS. 2 and 3 to succeed, it is essential that the thread 8 has a sufficiently large thread pulling force.

Claims (3)

1) Method for automatically winding a thread under tension on a spool or sleeve, characterized in that the thread under tension is placed several times by a gripper around the spool to be wound without overlaps, then the traversing is changed so that a second layer is wound over the first layer, as a result of which the bobbin itself generates a thread tension and the thread which has previously been drawn off from the new bobbin is cut. 2) .Use of the method according to claim 1 in a multi-position winding unit, characterized in that the reel to be wound is moved axially parallel next to the full bobbin and further wound the thread on the full bobbin during construction of the first layer on the new bobbin becomes. 3) Device for automatically winding a thread under tension on a bobbin or sleeve according to method 1, the thread being guided by a traversing eyelet which can be moved axially parallel over the bobbin width, characterized in that a deflection hook (5) is provided, which is on the axis of the spool to be wound (2) so far outside that the thread (8) from the traversing eye (3) to the deflection hook (5), also in the position where the traversing eye (3) is furthest from the deflection hook (5) is removed, does not touch the coil flange (6), that a device is present, the the thread from the traversing eyelet (3) is transported into the deflecting hook (5) such that a gripper (9) which rotates outside the flange (6) and is located between the traversing eyelet (3) and deflecting hook (5) is present, the rotational speed of which is adjustable , wherein the gripper (9) can pick up and carry the thread (8) running from the traversing eyelet (3) to the deflection hook (5) and that there is a thread separating device for the thread drawn off the bobbin (2) to be wound and corresponding control devices.

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