EP1868932B1 - Method and device for festooning a flexible material web - Google Patents

Abstract

The invention relates to a method and a device for depositing a flexible material web, said web being introduced into a folding unit and being deposited from said folding unit at a depositing point. The aim of the invention is to achieve higher production speeds with an excellent fold quality, even for material webs with a low weight. To achieve this, compressed air is applied to the material web after the latter has exited the folding unit in order to support the festooning process by means of a blower device.

Description

The present invention relates to a method and a device for depositing a flexible material web wherein the material web is introduced into a laying device and deposited from the laying device on a depositing point. It is particularly about the zigzag-shaped placement of the web over the laying length of the deposit.

Flexible webs are used in many areas of industrial processing. The material webs can be in the form of a textile fabric, such as woven, knitted fabric and nonwoven fabric, in the form of paper, natural, plastic or metal products, laminar composite materials or composites thereof. Also foamed and / or coated and / or fibrous products come as a flexible material web into consideration, which is further processed later.

Since webs are usually too narrow to be wound on rollers, a zig-zag-shaped depositing of the web in receptacles or on depositories, such as platforms or the like., In a plurality of layers, with significantly more meters of material can be accommodated when winding on rollers.

The method of zigzag depositing the material web is under the name "Festooning", the associated device under the name "Festooner" example. From the U.S. Patent 5,087,140 known. There, the web is deposited by means of a laying device on a platform that moves back and forth in the transverse direction. The laying device is formed by a laying arm, which is pivoted back and forth in the longitudinal direction.

From the DE 196 44 383 C1 also results as a laying device, a pivot arm over the width of the material web can be transported while the swivel arm moves. The material web is guided here between conveyor belts, which revolve around rollers, to the depositing point.

The U.S. Patent 3,735,554 discloses a device for laying strip material, wherein the laying means arranged above cartons are arranged on a longitudinally movable frame. The laying devices consist of only two rollers. The material exiting between the rollers of the laying device moves freely and unguided in the space above the cartons, which is disadvantageous in terms of an exact installation.

Other types of laying equipment relate to rollers, such as from DE 101 25 452 C2 and DE 91 16 502 U1 known. The laying rollers there are part of a movable with reversible orientation sled carriage. Between the laying rollers, the material web is transported to the depositing point. The material web is moved along with the laying rollers or the carriage over a certain laying length, which corresponds, for example, the width of a pallet.

From the US-A-4 958 819 is another laying device known.

All these known laying devices are of course functional, but then problems arise when the wind caused by the movement of the web and / or the laying device affects the depositing process, especially in material webs with low weight. Specifically, it can happen that the web does not reach the edge of the deposit and is then not detected by a hold-down or gripper. On the one hand, the space on the deposit is not optimally utilized, on the other hand, it can lead to wrinkles and thus to an impaired laying behavior and Legebild. Another disadvantage results in that the movement speeds must be relatively low, so that in particular webs can be stored with low weight. The higher the speed of the material web and / or the laying device, the stronger the air turbulences, which in turn lead to positional inaccuracies of the material web. The air influences are varied and different.

Using the example of a swivel arm at the time of the orientation change, the disadvantageous process becomes particularly clear. The web emerges from the swivel arm and while it moves down to the deposit, pivots the swivel arm and so to speak causes air resistance, wherein the depositing interrupted in the edge region and there provided for remaining material web section - the lighter the web is - retained and can no longer be detected by a hold-down or gripper. The process described for a swivel arm also applies in principle to a laying carriage with laying rollers.

Another difficulty is the electrostatic effects, on the one hand between the conveyor belt of the swing arm and the web and between the hold-down and the web, mostly due to plastic components in the material. On the one hand, the exiting material web is attracted to the conveyor belt, on the other hand, the already deposited material web is attracted by the hold-down. Particularly low-weight material webs are subject to the forces of attraction and there are problems when depositing. Similar effects are also known when depositing the web with laying rollers.

The known devices for depositing a flexible material web are thus nachbesserungsfähig, especially with regard to the deposition of a material web with low weight and high speed.

Based on the prior art, the present invention seeks to provide a method and apparatus of the type in question, with higher production speeds with good laying quality - even with material webs with low weight - can be achieved.

The above object is achieved with regard to the method by the features of claim 1.

According to the invention, it has first been recognized that higher production speeds with good laying quality - even with material webs of low weight - can be achieved if air turbulence and electrostatic effects are counteracted. It has also been recognized that the air turbulence and the electrostatic effects caused by the movements of the material web and the laying devices can be counteracted when the material web specifically supplied with compressed air. For example. Then, when the orientation change of the laying device takes place and this begins to move in the opposite direction and the intended for the edge region material web section is quasi "entrained" can be counteracted by compressed air. The compressed air also causes the material to be deposited to overcome the electrostatic attraction force which exists between the uppermost layer of the already existing material web stack and the hold-down device. This prevents incorrect orientation of the deposited uppermost layer of the material web.

But not only at the critical point of the orientation change, but also during the entire deposition over the laying length can be countered by a pressurized air the effect of air resistance or a suction effect by air currents and the electrostatic attraction. The material web leaving the laying device could be pressed constantly against the direction of movement of the laying device with compressed air to its depositing place and largely secured against displacement, wrinkling, curling. By applying compressed air to the material web, the force of attraction exerted by the laying device or its means of transport is also overcome.

In this way, even webs with a low density <50 g / m ² and a width of 35 mm at high speeds of over 150 m / min in the laying or Schwenkarmverfahren and well over 200 m / min in other laying methods and webs with A density of about 150 g / m ² and a width of 70 mm at high speeds of about 200 m / min when laying or Schwenkarmverfahren or 300 m / min are stored in other laying methods. In any case, with the known laying devices described above, these speeds can not be achieved.

The material web is continuously replenished while depositing and moved to the deposit or the material web stack. In order now to achieve the desired effect with the compressed air, this is suitably directed so that it impinges on the side of the web, which is to form the top of the uppermost layer of the material web stack. For this purpose, it is necessary that the compressed air is directed approximately in the direction of movement of the web and / or the laying device. There the compressed air to impinge on the top of the web, this is not completely parallel to the direction of movement of the laying device or the web of material, but is angled down to the impact on the web down.

Of particular advantage is the application of compressed air when the web is at the reversal point zig-zag depositing. Then the compressed air causes supporting, that the material web reaches into the area of a hold-down, in order to be temporarily fixed there if necessary.

According to the zigzag depositing process, the pressurization of compressed air could take place in an alternating manner in accordance with the orientation change of the material web and / or the laying device. For this purpose, two opposite blowing devices could be provided, each working in the opposite direction. The lighter and / or narrower the material web, the earlier the compressed air could be applied to the material web by the blowing device. As soon as possible, this takes place when the orientation change of the material web takes place and the pressurization of the opposite blowing device ends. In this case, there would be a continuous alternating pressurization of compressed air.

The heavier and / or wider the web is, the later the blowing process can begin. For example. For example, the pressurization of air by the one blowing device and the orientation change of the material web could already be completed when the pressurization of the compressed air takes place in the opposite direction. In this case, there would be a discontinuous alternating pressurization of compressed air. The more problematic the material, the more continuous the compressed air supply, which does not depend on the device, but rather on the material.

The subject of the present invention is furthermore a device which solves the object underlying the invention by the features of claim 8.

As with regard to the method, it has also been recognized with regard to the device that a targeted pressurization of the web of material can be counteracted by air movements caused by the movement of the material web itself or by the movement of the laying device and thereby a precise depositing at high speeds - even with material webs with low weight - is achievable.

Depending on what type of laying device is present, whether swivel arm or laying carriage or laying rollers, the material web is transported between means of transport in the form of rollers or rollers or belts to the deposit. A direct contact with the means of transport of the laying device ends at the end of the laying length or when the material web has reached the material web exit point.

Alternatively, the device according to the invention could also be used in connection with a laying device, wherein the material web is transported to the depositing place by means of suction devices or air chambers spaced apart from each other and partially oscillates freely between them. The local means of transport can also be present as a circulating belt, which seals the air chamber and at the same time the material web is sucked through the perforation.

Each of these different, mostly paired transport could be associated with a blowing device. In order that the transport of the material web is not impaired, the blowing devices could each be arranged at a small distance from the outer periphery of the transport means pointing away from the material web. The alternating movement of the material web requires two blowing devices with nozzle openings, which are arranged opposite one another. The nozzle openings could open into an area below the transport means, specifically in the region of the material web exit point, in order to allow a direct action. The nozzle openings could further be expediently oriented towards the material web, since the air jet is intended to impinge on the material web.

The blowing devices could be controlled by SPS control and specifically acted upon with compressed air. The compressed air loading of a blowing device could take place when a change of orientation takes place when depositing and the compressed air to the other blower ends. Here, however, depending on the properties of the material web, a discontinuous pressurization of the material web is conceivable. It is essential that the top of the web of material just laid is tensioned and kept smooth by the application of compressed air and the "overfeeding" takes place with material web in the edge region of the deposit, so that the web passes under the hold down or in the gripper and thereby also electrostatic attraction between holddown and previous uppermost layer of the material web stack as well as air resistance through movement overcomes.

Not only the alternating compressed air loading of the blowing devices could be controlled, but also the nozzle openings or the respective air flow could be adjustable to the respective width of the material web and / or their physical properties, such as weight, surface finish.

According to a preferred variant, the width of the nozzle opening corresponds to the width of the transport means of the laying device. This covers all web widths. If a material web is laid with narrower material web widths, the nozzle opening or the air flow can be adjusted to it. To adjust the air flow could be provided in the interior of the blowing devices mechanical slide or the like, which change the flow cross-section. In principle, the nozzle opening could also be smaller than the web width, which could, however, reduce the effect somewhat.

With regard to further advantageous embodiments of the device according to the invention, reference is made to the general description of the method according to the invention, especially as there features are explained, which are also relevant to the device.

Fig. 1

in schematischer, perspektivischer Darstellung, ein Ausführungsbeispiel der erfindungsgemäßen Vorrichtung,

Fig. 2

in schematischer perspektivischer verkleinerter Darstellung ein Detail des Gegenstandes aus Fig. 1 und

Fig. 3

in rein schematischer Darstellung, stark vereinfacht, Prinzipskizzen zum Verfahrensablauf während der alternierenden diskontinuierlichen Druckluftbeaufschlagung der Materialbahn bezüglich der Gegenstände aus den Fig. 1 und 2, bei

• 3a) Endphase der Druckluftbeaufschlagung in der Endstellung der Legeeinrichtung auf der einen Seite der Ablegestelle
• 3b) Start der Druckluftbeaufschlagung in entgegengesetzter Richtung
• 3c) Endphase der Druckluftbeaufschlagung in der Endstellung der Legeeinrichtung auf der gegenüberliegenden Seite der Ablegestelle.

There are now various possibilities for designing and developing the teaching of the present invention in an advantageous manner. On the one hand to the claims subordinate to claim 1, on the other hand, to the following explanation of an embodiment of the invention with reference to the drawing to refer. In connection with the explanation of the cited embodiment of the invention, generally preferred embodiments and developments of the teaching are explained. In the drawing show

Fig. 1

in a schematic, perspective view, an embodiment of the device according to the invention,

Fig. 2

in schematic perspective reduced representation of a detail of the subject matter Fig. 1 and

Fig. 3

in a purely schematic representation, greatly simplified, schematic diagrams of the procedure during the alternating discontinuous compressed air to the web with respect to the objects of the Fig. 1 and 2 , at

• 3a) End phase of the compressed air in the end position of the laying device on one side of the deposit
• 3b) Start of the compressed air supply in the opposite direction
• 3c) Final phase of the compressed air in the end position of the laying device on the opposite side of the deposit.

The Fig. 3 schematically shows the device according to the invention for depositing a flexible material web, which is suitable for carrying out the method according to the invention and has a laying device 1 for feeding the material web 2 to a depositing point 3.

According to the invention, the material web 2 is subjected to compressed air after it leaves the laying device 1 to support the laying process by means of two blowing devices 4, 5 arranged opposite one another.

at Fig. 3b ) but also in the Fig. 3a) and 3c ) It is shown that the compressed air impinges on the side of the material web 2 in accordance with the arrows A illustrating the direction of blowing, which is just to form the uppermost layer of a future, not yet existing material web stack. In this case, a smoothing and tension of the surface is achieved.

At the ends of the depositing station 3 hold-downs 6, 7 are provided in the present embodiment. The Fig. 3a) and 3c ) clearly show that the compressed air contributes to the fact that the material web 2 passes through overfeeding into the region of the respective hold-down 6, 7 in order to be temporarily fixed there. There, where the laying device 1 present as laying carriages has not arrived, since it has reached the end position for structural reasons, the compressed air blows the material web 2 out so that the hold-downs 6, 7 can detect them.

The compressed air is always directed according to the arrows A substantially in the direction of movement B of the laying device 1 of the web 2 and on the top thereof.

From the Fig. 1 and 3 it can be seen that two opposite blowing devices 4, 5 are provided. Depending on the orientation of the right to move B of the laying device they work in the corresponding blowing direction A.

In the present embodiment, the compressed air is started by the blowing device 5, as at Fig. 3b ), approximately in the middle of the laying length L of the depositing point 3. The direction of movement B in the direction of the blank holder 7 corresponds approximately to the blowing direction A, which is additionally oriented slightly downwards to the top of the material web 2. The hold-down 6, 7, both are in the holding position.

With increasing approach to the hold-down 7 this moves upward in the direction of movement C. Is the laying device 1 - as at Fig. 3c ) - arrived in the final position, there is the "overfeeding" or "belly training" of the web 2, which is supported by the compressed air in the blowing direction A.

On the depositing path back in the direction of hold-down 6 happens the same process, but in the reverse orientation. While the hold-down 6 in Fig. 3a ) is in the open position, hold-down 7 is in the holding position. The blowing device 5 has set before the orientation change the pressurized air and the blowing device 4 starts with the blowing process when the laying device 1 is approximately in the middle of the laying length L of the depository 3. The quality of the material web 2 requires no continuous application of compressed air here.

In the Fig. 1 and 3 Laying device 1 shown comprises transport means 8 in the form of rollers 9, 10 to rotate around the conveyor belts, not shown here for simplicity. The distance between the rollers 9, 10 to each other is adjustable according to the strength of the conveyor belts and thickness of the material web 2.

Each roller 9, 10 is associated with a blowing device 4, 5 at a small distance to their outer edge facing away from the material web 2. The nozzle openings 11, 12 of the blowing devices 4, 5, from the Fig. 1 and 2 are visible, are arranged opposite one another and open into a region below the rollers 9, 10 in the blowing direction A, so that the compressed air can impinge on the upper side of the material web 2 to be deposited.

The blowing devices 4, 5 can be controlled by SPS control and can be acted upon specifically with compressed air. For compressed air lines connections 13 are provided.

At 14 are in Fig. 1 denotes two holding plates, between which the rollers 9, 10 and the blowing devices 4, 5 are arranged and to which they are also attached. The attachment is done by screwing through unspecified passages. The rollers 9, 10 consist of an aluminum tube 15 a ball bearing 17 and a shaft 18 with frontal holes for attachment to the support plate 14. The laying device shown here can both a laying carriage, as in Fig. 3 shown, as well as in a swivel arm are used.

The width D of the nozzle opening 11, 12 corresponds in the present embodiment, the width E of the transport means 8, 9, 10 of the laying device 1, wherein the compressed air is selectively adjustable to the width of the material web 1.

With regard to further features, not shown in the figures, reference is made to the general part of the description.

Finally, it should be noted that the teaching of the invention is not limited to the embodiment discussed above. Rather, the most varied designs of blowing devices, laying devices, transport mechanisms and various embodiments of the nozzle openings and control concepts are possible.

LIST OF REFERENCE NUMBERS

1

securing device

2

web

3

departure point

4

blower

5

blower

6

Stripper plate

7

Niederhalterr

8th

Mode of Transport

9

role

10

role

11

nozzle opening

12

nozzle opening

13

roller pair

14

Retaining plate

15

Alurohr

16

ball-bearing

17

Shaft with hole

A

blowing direction

B

Movement direction of 1

L

folding length

C

Movement direction of 6, 7

D

Width of 11, 12

e

Width of 8, 9, 10

Claims (16)

1. A method for depositing a flexible material web, wherein the material web (2) is introduced into a laying device (1) and is deposited from the laying device (1) at a depositing point (3), particularly in a zigzag manner, wherein compressed air is applied to the material web (2) in order to support the depositing process,
   characterized in
   that the material web (2) is guided within the laying device (1) between two means of transport (8), which are used in pairs, and contacts one of the means of transport (8) until said material web (2) exits the laying device (1) and in that compressed air is applied to the material web (2) only after the latter has exited from the laying device (1).
2. Method according to claim 1 characterized in that compressed air hits that upper side of the material web (2), which forms the topmost layer of a stack of material webs.
3. Method according to claim 1 or 2, characterized in that compressed air contributes to the arrival of the material web (2) into the region of a hold-down device (6, 7) or gripper in order to be fixed there temporarily.
4. Method according to one of the claims 1 to 3 characterized in that the application of compressed air alternates correspondingly to the change in orientation of the material web (2) and/or of the laying device (1).
5. Method according to one of the claims 1 to 4 characterized in that compressed air is oriented, for example, according to the direction of movement (B) of the material web (2) and/or of the laying device (1).
6. Method according to one of the claims 1 to 5 characterized in that two opposite blower devices (4, 5) are provided, each of which operates in the opposite direction (A), and wherein the earliest possible time for applying compressed air to the material web (2) using one blower device (4) is when a change in the orientation of the material web (2) and/or of the laying device (1) has taken place and the application of compressed air to the material web (2) by the opposite blower device (5) has ended.
7. Method according to claim 6 characterized in that, depending on the properties of the material web (2), one blower device (4) starts the repeat application of compressed air to the material web in the opposite direction (A) in a time-shifted manner at the end of the application of compressed air by the opposite blower device (5).
8. An apparatus for depositing a flexible material web, particularly for implementing the method according to one of claims 1 to 7, said apparatus comprising a laying device (1) for supplying the material web (2) to at least one depositing point (3), wherein the laying device (1) comprises at least one blower device (4, 5), which applies compressed air to the exiting material web (2) in order to support the depositing process,
   characterized in
   that the laying device (1) comprises two means of transport (8), which are used in pairs, between which the material web (2) passes to arrive at the exit point and in that the material web (1) contacts one of the means of transport (8) until said material web (2) exits the laying device (1).
9. The apparatus according to claim 8, characterized in that the means of transport (8) are present in the form of belts, rollers (9, 10), cylinders, along which the material web (2) passes to arrive at the exit point.
10. The apparatus according to claim 8 or 9, characterized in that one blower device (4, 5) is assigned to each of the means of transport (8), which are used in pairs.
11. Apparatus according to claim 10 characterized in that the blower devices (4, 5) are each disposed at a small distance from that outer circumference of the means of transport (8) that points away from the material web (2).
12. Apparatus according to claim 10 or 11 characterized in that nozzle outlets (11, 12) of the blower devices (4, 5) are disposed opposite to each other and open into a region located below the means of transport (8) and are each oriented towards the exiting material web (2).
13. Apparatus according to one of the claims 8 to 12 characterized in that the blower devices (4, 5) can be controlled by a PLC (Programmable Logic Controller) and pressurized with compressed air in a targeted manner.
14. Apparatus according to claim 13 characterized in that the application of compressed air by a blower device to the material web takes place when a change in the orientation of the material web and/or the laying device has taken place and the application of compressed air by the opposite blower device has ended.
15. Apparatus according to one of the claims 12 to 14 characterized in that the width (D) of the nozzle outlet (11, 12) corresponds at least to the width of the material web (2), preferably the width (E) of the means of transport (8) of the laying device (1).
16. Apparatus according to claim 15 characterized in that the application of compressed air can be adjusted to the width of the material web (2) if the width (D) of the nozzle outlet (11, 12) corresponds to the width (E) of the means of transport (8) of the laying device (1).

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