EP1752403A1 - Device for threading webs - Google Patents

Abstract

An accessory device (21) has a first holding element (31) that extends crosswise to a paper web's (9) longitudinal span and across the width of the paper web and is held on both sides of the paper web in carriers (33,34) on either side, one of which has a rotary drive (36). Fastened on one or more carriers there is a second holding element (32).

Description

The invention relates to a device for guiding a web from a first position to a second position, in particular from an unwinding station to a winding section of a reel winder, with an auxiliary device which engages the web at the first full-width position.

The invention will be described below using the example of a reel winder. Here, a web, in particular a paper web, withdrawn from a supply roll, passed through a longitudinal cutting device and then fed to a winding section, where the then present in partial webs web is wound on partial web rolls. These partial web rolls can be wound, for example, in a double take-up roll winder or in a support or contact roll winder.

At least during initial commissioning, but usually also in certain business interruptions, the web must be guided from the unwinding station to the winding section.

For this so-called threading or inserting operation, it is common to tip the web, i. with a section that has a much smaller width than the web itself. Although such a tip is much easier to handle than the web in full width. But it has the disadvantage that a non-negligible part of the web is lost. In particular, one can not enter the longitudinal cutting knife into the web until the web has arrived at the winding section with full width.

One has therefore in the older one German patent application 10 2004 049 720 proposed to detect the web with an auxiliary device and then to guide the auxiliary device along the predetermined path. For this purpose, it is necessary that the auxiliary device can detect the web over its full width.

The invention has for its object to easily detect a web in the region of its beginning in full width.

This object is achieved in a device of the type mentioned above in that the auxiliary device comprises a first holding element, which is transverse to the Longitudinal extent of the web and at least over the width of the web extends and is held on both sides of the web in a carrier, at least one of which has a rotary drive, wherein at least one support a second holding element is attached, which in a receiving state a distance from the first holding element has, through which the web is insertable, and both holding elements are pressed against each other by a train of the wound around the holding elements web.

With such an auxiliary device, the detection of the web in the region of its beginning is extremely simple. The beginning of the web must only be passed between the two holding elements. This is easily possible because the two holding elements in the receiving state have the necessary distance from each other. So there is a gap between the two holding elements. Once the web has been threaded into this gap, you can rotate the two carriers. After less than one revolution, the two holding elements are pressed against each other by the web so that they pinch the web between them. Therefore, no additional actuators are needed to close the gap between the two holding elements. The force necessary for closing is applied by the train itself. For safety reasons, you can rotate the carrier over more than one revolution, so that the beginning of the web is securely held between the two holding elements. The carriers with the intervening Retaining elements can then be moved by a guide system from the first position to the second position along a predetermined path. Thus, the two carriers can each be mounted in rails or the like. Once the web has reached the second position, you can either sever the web so that it is released from the auxiliary device, or you turn the carrier backwards until no train is present and the web exerts no clamping force on the two holding elements. You can then pull the web out of the gap between the holding elements.

Preferably, at least one of the retaining elements is designed as a pressure-force-free retaining element. A pressure-force-free holding element can be deformed with relatively little force transversely to its longitudinal extent. Thus, if lateral forces are exerted on this holding element via the web pull, then this holding element is moved in the direction of the other holding element and then clamps the web between the two holding elements.

It is preferred that at least one of the holding elements is designed as a rope. Of course, both retaining elements may be formed as a rope. When the two carriers are rotated, on the one hand, the web is wound around a rope and, on the other hand, the other rope is pressed against the first rope, so that the web is held by two forces. These are on the one hand frictional forces in the manner of a rope friction and on the other hand clamping forces, which are caused by the opposing ropes.

In a preferred embodiment, it is provided that at most one of the holding elements is designed as a rod. Under rod should also be understood a pipe. Such a rod is capable of transmitting torque from one carrier to the other carrier so that it is sufficient to drive one of the carriers. A bar is a forceful element, i. it can be applied transversely to the longitudinal extent of the web with a compressive force. A rod thus ensures at the same time that the two carriers always have the necessary distance from each other.

In an advantageous embodiment it is provided that one of the holding elements is designed as a rigid arm which is pivotally mounted on the carrier. The fact that the arm is rigid, he holds in the unfolded state, even if he is not connected to the other carrier, in a predetermined position. In this position, the arm and the other holding member form, so to speak, a kind of open pliers, in which the web can be introduced. When the carriers are then rotated, at the latest when the arm is wrapped in the web, the web presses the arm against the other holding member so that the web is clamped between the arm and the other holding member. Since the web is applied at the same time over its width and with a certain enclosing angle on the other holding element, the web is again detected over its full width safe and can then be pulled from the first to the second position.

It is preferred that the arm has a length which is at most 30% of the width of the web. So the arm itself does not work on the entire width of the web. If the carriers are spaced out of the way, the arm will act on the web even less than 30% of its length. However, this is sufficient because the trapped web, even if it is held only at one part of its width, forms a sufficient frictional force on the other holding element, so that it can be safely pulled over its entire width.

Preferably, the arm is biased away from the other retaining element. So if the web tension decreases, for example, when the carrier is rotated backwards or the web is severed, then the arm opens automatically, so that the web can be pulled out until the auxiliary device for receiving a new web start is available.

Preferably, an arm is arranged on each support. The web is thus taken in the region of its two longitudinal edges. This improves the reliability.

Fig. 1

eine Rollenwickeleinrichtung in schematischer Darstellung,

Fig. 2

eine erste Ausgestaltung einer Hilfseinrichtung,

Fig. 3

die Hilfseinrichtung in Seitenansicht und

Fig. 4

eine zweite Ausgestaltung einer Hilfseinrichtung.

The invention will be described below with reference to preferred embodiments in conjunction with the drawings. Herein show:

Fig. 1

a roller winding device in a schematic representation,

Fig. 2

a first embodiment of an auxiliary device,

Fig. 3

the auxiliary device in side view and

Fig. 4

a second embodiment of an auxiliary device.

Fig. 1 shows a schematic representation of a roll winding device 1 with an unwinding station 2 and a winding station 3. Between the unwinding station 2 and the winding station 3, a longitudinal cutting device 4 is arranged.

In the unwinding station 2 an unwinding position 5 is provided. In the unwinding position 5 is a pay-off bearing 6, in which a spool 7 is rotatably mounted. On the spool 7, a master roll 8 aufgewikkelt, of which a remainder is still visible in Fig. 1. From the parent roll 8, which may also be referred to as a "jumbo roll", a web 9 is withdrawn. This web 9 is cut in the slitter 4 in several sub-webs and wound in the winding station 3 to several bobbins 10, of which in Fig. 1 only one can be seen because these bobbins 10 are in a direction perpendicular to the plane behind the other.

The unwinding 6 is suitable for higher speeds. For example, the web 9 can be withdrawn at a speed of 2000 to 3000 m / min. On the opposite side of the main cylinder 7 of course a similar Abwickellager 6 is arranged.

The winding rollers 10 rest on two support rollers 11, 12, of which at least one is driven. A loading roller 13 may be provided to control the winding process. Instead of the illustrated so-called "Doppeltragwalzenwicklers" may also be provided a back-up roll winder, in which the winding rollers 10 are held centrally and bear against a support or contact roller.

The unwinding station 2 also has a preparation position 14, in which a further reel 15 with a new master reel 16 is kept ready. The preparation position has a preparation bearing 17, which also allows a rotation of the main cylinder 15, but is less expensive, because the necessary rotation speeds are much lower. The preparation bearing 17 and the unwinding bearing 6 are interconnected by a track 18 on which the spool 15 in the preparation position 14 to the unwinding position 5 can roll when a reel change is required.

In the preparation position 14, the mother roll 16 is prepared. As a rule, some layers of the web are handled and disposed of in preparation. This process is also referred to as "skimming". For receiving the portion of the web 9 to be disposed of, a pulper opening 19 is provided, which is arranged below the preparation position 14 in such a way that under the action of gravity hanging down web 9 hits the pulper opening 19. Although the parent roll 16 does not always have the same radius, the position of the depending web 9 will move slightly. However, the pulper opening 19 is so large that it can catch the falling web. Optionally, a hopper 20 may be additionally provided.

It is now occasionally necessary to guide the web 9 from the unwinding station 2 to the winding station 3. The web 9 must also be guided by the longitudinal cutting device 4. This process is also referred to as "inserting".

For insertion, the roll winding device 1 an auxiliary device 21, which is shown in Fig. 1 at different positions. In different positions, the auxiliary device 21 is provided with small letters (a, b, c) for distinction.

The auxiliary device 21 is guided on a movement path 22, which is shown as a dashed line. The trajectory is realized by rails or guides, which are arranged on both sides of the web 9 outside its width. Along the path of movement 22 may also be a chain, a belt or a rope out be, these devices are driven in a manner not shown by a common drive, so that the auxiliary device 21 can be performed in an orientation perpendicular to the direction of movement of the web 9 from the unwinding station 2 to the winding station 3.

The auxiliary device 21 is now moved from the left (relative to the illustration of Fig. 1) to the under the action of gravity vertically hanging down web 9 and attached to the web.

2 shows a first embodiment of an auxiliary device 21 for detecting the beginning of the hanging of the parent roll 16 end of the web 9. The auxiliary device 21 has two ropes 31, 32 which are spanned between two carriers 33, 34. The two cables 31, 32 have a length which is greater than the width of the web 9. The distance between the two carriers 33, 34 corresponds to the length of the cables 31, 32. It can be seen that the carrier 33, 34 with Distance are arranged laterally next to the web 9.

Between the two ropes 31, 32 remains in the receiving state shown in Fig. 2, a distance 35 through which the beginning of the web 9 can be performed. Basically, it is only necessary for this to position the auxiliary device 21 in the direction of gravity under the track 9. Optionally, use is made of a cross cutting device 23 which separates a superfluous portion 24 (see FIG. 1) and into the pulper 19 dropping. The master roll 16 is then rotated slightly backwards until the beginning of the web is in the direction of gravity slightly above the ropes 31, 32. Thereafter, the auxiliary device 21 can be positioned and the web 9 then occurs at a forward rotation of the parent roll 16 in the distance 35, which may also be referred to as a gap or gap, a.

At least one of the two carriers, in the present case the carrier 34, is provided with a rotary drive 36, which acts on the carrier 34, for example via a belt or a chain, in such a way that it can be rotated. In the same way, of course, the other carrier 33 may be provided with such a rotary drive. The carriers 33, 34 are each rotatably supported on holders 38, 39. These holders 38, 39 can then be guided along the path of movement 22.

When the two carriers 33, 34 are rotated, then the two cables 31, 32 come after a revolution of about 90 ° to bear against the web 9. Another rotation then causes the web 9 wraps around the two sides. Since at least the portion of the web hanging from the master roll 16 is held under some tension by the braked master roll 16, rotation of the supports 33, 34 causes the two ropes 31, 32 to move towards and be pressed against each other , So you clamp the web 9 between them. The clamping force is here alone applied over the web 9, more precisely on the tensile stress, which sees the web 9 suspended.

The clamping force acts practically over the entire width of the web 9. It is usually sufficient even after only one revolution of the carrier 33, 34 to reliably hold the web 9 between the two ropes 31, 32.

However, there is still the friction that acts between the ropes 31, 32 and the web 9 in the areas in which the web 9 rests only on the ropes 31, 32. However, since the web 9 is clamped with its front end, caused by the wrap angle frictional force between the web 9 and the two ropes 31, 32 act reinforced so that the web 9 already after one or at least a few turns of the carrier 33, 34 is reliably held between the ropes 31, 32.
To hold the web 9, only a small portion at the front end of the web 9 is consumed. The length of this section is in the range of a few 10 cm.

When the auxiliary device 21 has arrived in the area of the winding device 3, it is expedient to sever the web in order to cut off and dispose of the area of the web clamped and wound between the cables 31, 32.

The disposal can, moreover, be effected via the pulper 19, when the auxiliary device has been transported back there with the still wound-up remainder of the web.

The two ropes 31, 32 form pressure-free holding elements. Pressure-free holding elements can be easily deflected transversely to their longitudinal extent.

It is also possible to replace one of the two cables 31, 32 with a rod, so that during one rotation of the carrier 33, 34 the remaining cable is pressed against the rod.

Fig. 4 shows a modified embodiment, which basically works on the same principle.

The auxiliary device 21 according to FIG. 4 has as a holding element a tube 40, which is rotatably mounted in the two carriers 33, 34. The tube 40 may have as a drive, for example, a tubular motor.
On each carrier 33, 34 an arm 41, 42 is articulated. Each arm 41, 42 is rigid in itself. It is biased in the position shown by solid lines by a spring, not shown, but can be pivoted to the position shown in dashed lines, as will be explained below.

Each arm 41, 42 has only a limited length. The length of an arm 41, 42 is at most 30% of the width of the web. 9

For threading the web 9 is passed through the openings 43, 44, which result between the tube 40 and the unfolded arms 41, 42. In this case, the web 9 should survive at least the width of the arms 41, 42 down over the arms 41, 42. Appropriately, but a larger supernatant is set.

To clamp the web 9 on the tube 40, the tube 40 is now rotated counterclockwise, so that the free ends of the arms 41, 42 against the force of gravity to move up.

After a little less than 90 ° rotation, the arms 41, 42 then come into contact with the web 9 and are pressed against the tube 40 in another revolution. In doing so, they clamp the web 9 between themselves and the pipe 40. The clamping force acts only on the edge region of the web 9 and is usually not enough to reliably guide the web 9 to the winding station 3. Accordingly, the tube 40 is rotated further and that expediently until the web 9 is wound on the tube 40 by at least one revolution. Since the web 9 is clamped between the tube and the arms 41, 42, then the tension exerted by the braked mother roll 16 is sufficient to hold the web 9 with the necessary frictional force on the circumference of the tube 40.

When the web 9 has been guided into the area of the winding station 3, the tube 40 can again be turned backwards. Once the arms 41, 42 come free, they unfold and the web 9 is free for further handling.

Claims (8)

Device for guiding a web from a first position to a second position, in particular from an unwinding station to a winding section of a reel-winding device, with an auxiliary device which engages the web at the first full-width position, characterized in that the auxiliary device (21) engages first holding element (31; 40) which extends transversely to the longitudinal extent of the web (9) and at least over the width of the web (9) and is held on both sides of the web (9) in a respective carrier (33, 34) at least one of which has a rotary drive (36), wherein at least one carrier (33, 34) a second holding element (32; 41, 42) is fastened, which in a receiving state a distance (35; 43, 44) to the first holding element ( 31, 40), through which the web (9) is insertable, and both holding elements (31, 32, 40, 41, 42) by a train of about the holding elements (31, 32, 40, 41, 42) wound web (9) can be pressed against each other d. Apparatus according to claim 1, characterized in that at least one of the holding elements (31, 32; 41, 42) is designed as a pressure-force-free holding element. Apparatus according to claim 1 or 2, characterized in that at least one of the holding elements (31, 32) is formed as a rope. Device according to one of claims 1 to 3, characterized in that at most one of the holding elements (40) is designed as a rod. Device according to one of claims 1 to 4, characterized in that one of the holding elements as a rigid arm (41, 42) is formed, which is pivotally mounted on the carrier (33, 34). Apparatus according to claim 5, characterized in that the arm (41, 42) has a length which is at most 30% of the width of the web (9). Apparatus according to claim 5 or 6, characterized in that the arm (41, 42) is biased away from the other holding element (40). Device according to one of claims 5 to 7, characterized in that an arm is arranged on each support (33, 34).

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