EP1516838A2 - Device for processing stacks of electrostatic rechargeable flat parts - Google Patents

Abstract

The device for the processing of a multi-layered electrostatically chargeable material web (10) has a cutting device (2) for the cutting of the material web into corresponding sheets lying one above the other, an electrostatically charging device (30), and a first and a second feed unit (20) for the transporting of the material web. The electrostatic charging device is located adjacent to the cutting device in the region of the first or the second feed unit, and may be located between the cutting device and the first and second feed device.

Description

The invention relates to a device for processing a multilayer electrostatically chargeable web, with at least one Cutting device for cutting the multilayer web in corresponding superimposed arches, an electrostatic Charging device for electrostatic charging of the multilayer Material web and located upstream of the cutting device first and one downstream of the cutting device located second conveyor for transporting the multilayer Web.

When transporting a multilayer web or cut from it overlying sheets in the paper-making Industry, for example from one processing station to another, to a stacker or to a packaging machine, are the Arcs due to accelerations or decelerations due to the Conveying devices, branches u. Like. Particularly endangered. Especially at high accelerations and abrupt changes of direction of the transport path, the superimposed Slips in it. That's why the transport way and the formation of the conveyors high demands to deliver; because slipped, out of shape let pile of sheets refrain from further processing or packaging.

It is therefore proposed in DE 35 085 14 A1, paper stacks electrostatically recharge, leaving it in shape for further processing temporarily fixed. This way you can prevent that in particular when accelerating in a conveying device the Stack to slip in or even fly off the individual leaves.

DE 101 28 653 A1 teaches the use of an ionization device, by means of the sheet layers in a conveyor electrostatically are rechargeable. In this known conveyor is in the area a front conveying device arranged a suction device, by means of the sheet layers in at least a portion of the sheet layers be acted upon with suction.

The invention now proposes, in a device of the aforementioned Type the electrostatic charging device in the area of first or second conveyor adjacent to the cutting device to arrange.

Accordingly, according to the invention, the electrostatic charging device adjacent or in immediate proximity to the cutting device arranged. In this way, the risk of congestion of the multilayered Material web avoided in the cutting device and thus the risk of damage to the relatively expensive cutting device significantly reduced.

Here is an arrangement of the electrostatic charging device both upstream of the cutter and downstream conceivable behind the cutting device. In particular, the should electrostatic charge take place behind the cutting device. Because it has turned out according to the invention that it is easier an already cut and then electrostatically charged web with the help of the second conveyor deduct as one already previously electrostatically charged web through the cutting device to push. In this case of electrostatic charging downstream behind the cutting device, it is also conceivable on the upstream of the cutting device located first conveyor Optionally also to renounce.

According to a preferred embodiment of the invention, the electrostatic Charging device substantially between the cutting device and the first upstream or upstream of this downstream of this second conveyor be arranged, which, however, facing an overlapping arrangement the first or second conveyor does not preclude, provided the electrostatic charging device adjacent to the cutting device is arranged so that an electrostatic charge of the Material web substantially immediately before or after cutting can take place.

Preferably, at least the downstream of the cutting device located second conveyor an endlessly circulating Conveyor belt assembly consisting of only one or more sub-bands needs to exist on the one or more of the multi-layered Material web cut superimposed arches rest. Due to the fact that due to the electrostatic charge the arcs in are fixed, upper bands in the second conveyor omitted. The omission of the upper band path leads to considerable constructive Simplifications and thus significant savings.

Also, not as in the prior art adjustments such as Adjust the tape positions to the formats or settings the friction of the lower bands to the upper bands necessary. Furthermore is by eliminating the upper strip web the second conveyor Easily accessible from above, which makes it easier to eliminate interference to let. Finally, by the topless free transport reduced the risk of damage to the transported sheets, which is especially true for coated paper sheets due to their high sensitivity is particularly relevant.

To increase the friction for secure transport of the bows can in a further preferred embodiment, the second conveyor have a suction device, expediently a Upper run of the conveyor belt assembly above the suction device running. If the suction device has a suction surface, a should upper run of the conveyor belt assembly on such a suction surface rest. To increase the suction should at least a sub-band be perforated.

Preferably, the electrostatic charging device around an ionizing device.

The cutting device should in particular have a cross cutter.

According to another aspect of the present invention is a Device for processing a multilayer, electrostatically chargeable Material web to individual superimposed sheets with a Conveying device for transporting the superimposed sheets an electrostatic discharge device for electrostatic discharge the arches and one downstream of the conveyor stack tray to form stacks of the superimposed Arches proposed in which the electrostatic discharge device is arranged in the area of the stack tray.

Unless the multilayer material web through the previously described Device and / or electrostatic charging devices on others Placing the machine, in particular behind the cutting device, specifically electrostatically charged, which can during the rest Processing process occurring relative movements between Machine components and the material and / or within of the material depending on the material and the environmental conditions lead to electrostatic charges. This electrostatic Charges can change the further processing process in one hinder subsequent device. For the neutralization of the electrostatic charged material are in the range of the conveyor solid antistatic units installed across the entire working width, who try to unload the material passing by them. The short residence time of the material under these antistatic units during However, the transport does not lead to the desired complete Discharge. In addition, the material tends on its further way to the stack tray to recharge. Therefore, the invention proposes before, the electrostatic discharge device in the field of Stack tray to arrange where the from the multilayer web cut sheets come to rest and thus a sufficient Dwell time for a complete discharge of the sheets is present. This completes the electrostatic adhesion between the sheets eliminated, which also a faultless alignment and stacking allows the arches.

Preferably, the electrostatic discharge device is in the upstream Section, preferably on the upstream side, the stack tray arranged.

Another presently preferred embodiment of the invention is characterized in that the electrostatic discharge device a compressed air device for generating compressed air, a Device for electrostatically charging the compressed air with opposite the arcs opposite polarity and a blowing device for Having bubbles of this air against the arches. Because the emergence of a Air cushion between the sinking sheets in the stack tray provides in conjunction with mechanical piecing elements for a precise Edge formation of the resulting stack. The formation of such Air cushion is already known. The invention now uses the required for this Compressed air at the same time in a clever way to the necessary electrostatic Discharge the bows by using the compressed air with respect to the Arcs of opposite polarity is charged. Thus, by the selective introduction of blowing air with electrostatic discharging effect both the aforementioned air cushion provided at the exact location, where the effect must necessarily be present, namely in the Stacking tray, as well as an electrostatic neutralization of the sheets achieved.

Preferably, the blowing device substantially blows the air the trailing edges of the arches.

Expediently, the blowing device has a nozzle arrangement on.

In a further preferred embodiment of the invention, the electrostatic sits Discharge device in a housing, of which one section the stack tray is limited and preferably a stop for the piles forms. Thus, the case can also function at the same time take over a stack stop. It should be the stack tray limiting portion of the housing having the blowing device. For this purpose, the portion of the housing limiting the stacking tray be provided with openings for blowing out the air. These Openings are designed so that they accelerate the exiting Air with electrostatic discharge in the direction of allow the forming stack. Appropriately exists the housing made of an electrically non-conductive material.

In particular, the electrostatic discharge device is concerned around a deionizer.

Finally, in the lower portion of the stack tray suction means be provided, the disturbing with negative pressure air between the sucks up stacking sheets.

Fig. 1

in schematischer Seitenansicht ausschnittsweise einen eine lonisiervorrichtung aufweisenden Abschnitt einer papierverarbeitenden Maschine mit Anordnung der lonisiervorrichtung vor einem Querschneider;

Fig. 2

in schematischer Seitenansicht ausschnittsweise einen eine lonisiervorrichtung aufweisenden Abschnitt einer papierverarbeitenden Maschine, welche sich von Figur 1 lediglich in der Anordnung der lonisiervorrichtung hinter dem Querschneider unterscheidet;

Fig. 3

eine Draufsicht auf den Abschnitt einer papierverarbeitenden Maschine von Figur 1 bzw. Figur 2 unter Weglassung der lonisiervorrichtung; und

Fig. 4

schematisch im Querschnitt ausschnittsweise einen eine Entionisiereinrichtung aufweisenden weiteren Abschnitt einer papierverarbeitenden Maschine.

Hereinafter, preferred embodiments of the invention will be explained in more detail with reference to the accompanying drawings. Show it:

Fig. 1

a schematic side view of a section of an ionizing device having portion of a paper processing machine with arrangement of the ionizing before a cross cutter;

Fig. 2

a schematic side view of a section of an ionizing device having portion of a paper processing machine, which differs from Figure 1 only in the arrangement of the ionizing behind the cross cutter;

Fig. 3

a plan view of the portion of a paper processing machine of Figure 1 and Figure 2, omitting the ionizing device; and

Fig. 4

schematically in cross-section detail a Deionisiereinrichtung having another section of a paper-processing machine.

A first section of a paper processing machine with a Cross cutter 2 is fragmentary in Figures 1 and 2 in more schematic Side view in two different versions and in Figure 3 is shown generally in plan view. The cross cutter 2 points in the illustrated embodiments, a first knife roller 4 with one extending over the entire length of the knife roller 4 first knife 5 and a second knife roller 6 with a on the entire length of the knife roller 6 extending second knife 7. The two knife rollers 4, 6 rotate synchronously in opposite directions Direction to each other in a way that the two male connectors 5, 7 hit to a running between the two knife rollers 4, 6 multilayer paper web 10 in single superimposed Bows 12 to cut. In contrast to Figure 2 are in Figure 1, the multilayer paper web 10 and the individual cut therefrom superimposed sheets 12 each only as a continuous Dash shown schematically; this also applies to Figure 4, the rest will be explained in more detail later.

For transporting the multilayer paper web 10 in the direction of Arrow A is upstream of the cross cutter 2, a first conveyor provided, which is not shown in the figures. Further is downstream of the cross cutter 2 downstream of a second conveyor 20 arranged, the at least one via guide rollers 22, 24 endless circumferential lower band 26 having, with its upper run 26a in the direction of arrow A runs. Usually there are several sub-bands 26 arranged transversely to the direction of the sheets 12 according to arrow A next to each other.

In the first embodiment of Figure 1 is upstream of the Cross cutter 2 adjacent to this and thus between the not shown first conveyor and the cross cutter 2 a Ionizing device 30, which the multilayer paper material web 10 static charges. Preferably, the ionizing device consists 30 from a direction transverse to the paper direction according to arrow A extending Ionizing bar. By the ionizing device 30 is achieved in that the individual paper layers of the multilayer paper material web 10 and thus the subsequently cut by the cross cutter 2, superimposed sheets 12 adhere to each other and not against each other can slip.

In contrast, in the second embodiment according to FIG. 2, the Ionization device 30 downstream behind the cross cutter. 2 adjacent to this and thus substantially between the cross cutter 2 and the second conveyor 20 is arranged.

Behind the cross cutter 2, the separated sheets 12 on the Subbands 26 of the second conveyor 20 transported, wherein the individual sheets 12 not because of the electrostatic charge can open. To increase the friction between the sheets 12 and the upper run 26a of the lower belts 26, suction boxes 40 are provided, the top of which forms a suction surface 42, via each one Upper run 26a of the upper belts 26 runs. The suction boxes 40 are on connected to a suction pump, not shown. The suction surfaces 42, which carry the upper run 26a of the lower straps 26 are perforated, such as Figure 3 reveals. To the suction power in the range of subbands 26, these are also perforated accordingly, resulting in Figure 3 is also shown schematically. Due to the suction effect of Suction boxes 40 are the superimposed and by the electrostatic Charging adhering sheets 12 against the upper Runs 26a of the subbands 26 are pulled, reducing the friction between the bends 12 and the moving subbands 26 and thus the adhesion of the sheets 12 is increased to this. In this way a secure transport of the sheets 12 is ensured by the sub-bands 26, so that even higher transport speeds possible are.

Moreover, it is conceivable, the suction surfaces 42 and optionally the Suction boxes 40 in paper direction according to arrow A not, as in the Figures 1 to 3 shown schematically, continuously, but alternatively shared or divided several times. Furthermore, it is conceivable that Suction boxes 40 for adjustment and maintenance work removable, in particular pivotable downwards, to arrange. Finally, in particular for a format change the suction of each selected Suction boxes 40 are turned off or turned on, which advantageous for maintaining a constant negative pressure is.

The advantage of the arrangement described above is in particular in that in the second conveyor 20, the sheets 12 to a subsequent overlapping station not shown in the drawings transported, waived the usual upper bands can be. Therefore, the second conveyor 20 has no Upper bands, whereby the second conveyor 20th formed conveyor line structurally simplified and operatively accessible becomes.

In Figure 4 is schematically in cross-section detail another Section of the paper processing machine in the area of a stacking tray 50, in which the overlapping incoming sheets 12 are stacked to a stack 14.

Paper processing machines, the web-shaped materials of one or multiple rolls and process to format material are in the majority of cases designed so that inside the machine a flaky overlapped stream of sheets 12 is generated. These Dandruff shape is necessary to avoid from the high web-off-take and Transport speed, for reasons of plant productivity is selected in the section shown in Figures 1 to 3, on the lowest possible speed for the formation of the stack 14th get.

Unless a targeted electrostatic charge takes place, as before has been described with reference to the figures 1 to 3, lead during the further processing process taking place relative movements between the machine components and the material or within of the material depending on the material chosen and the environmental conditions to electrostatic charges. While such static charges initially during transport the second conveyor 20 (Figures 1 to 3) are desired hinder They more or less the formation of a clean stack 14 and in particular the subsequent further processing in other stations or devices, here then the productivity and the quality of further processing is significantly reduced can be.

For this purpose, an all-sided closed housing 60 is provided, the a non-conductive material. The housing 60 has a Compressed air connection 62, which is connected to a compressed air source, not shown is connected and by the compressed air in the direction of arrow B in the housing 60 is pumped. With its one side 64 this limits Housing 60, the stack tray 50. This stack tray 50 facing Side 64 of the housing 60 forms in the illustrated embodiment a vertical planar surface to which the stack 14 is engageable. Thus, in the illustrated embodiment, the page takes 64 of Housing 60, the function of the rear stack stop and takes over at the same time the pitching function. Thus, this vertical Page 64 of the housing 60 may also be referred to as a rear-mounted implement.

In the conveying direction, the stack tray 50 by a front-end 68 limits that promoted as a stop for the stack tray 50 Arches 12 is used and essentially arranged vertically Plate bodies consists. Accordingly, the stack tray 50 are facing Page 64 of the housing 60 and the front-end user 68 parts of a Anrichtmechanismus or form the Anrichtmechanismus.

Further, in the stack tray 50 facing side 64 of the housing 60 a plurality of nozzle-shaped air outlet openings 66 are formed, in such a way that they over the entire working width in regular Distances form perpendicular drilling patterns. These openings 66 are designed so that they have an accelerated exit the entering through the compressed air connection 62 compressed air in the direction achieve on the forming stack. The resulting air flows occur substantially in the longitudinal direction of the stack 14 forming Arches 12 and are directed to the rear edges 12 a. In this way arise in the stack tray 50 between the sinking Bows 12 air cushions, in conjunction with the already mentioned, but not shown piecing mechanism for an accurate edge formation of the resulting stack 14. Because for the education of the stack 14, it is necessary that the sheets 12, which are in scaly run in overlapping arrangement against the front end 68, both a good relative shift with each other and the Float on an air cushion when sinking to the surface of the forming stack 14 is made possible.

For electrostatic discharge of the sheets 12 is in the illustrated embodiment within the housing 60 a de-ionizer 70, which preferably consists of an antistatic rod. These Deionizer 70 ionizes the through the compressed air port 62nd in the housing 60 incoming compressed air with respect to the sheets 12th opposite polarity, so that from the outlet openings 66 exiting compressed air at the same time a deionizing effect on the Arches 12 of the forming stack 14 exerts. Thus, by the targeted introduction of blowing air with deionizing effect in the forming stack 14 both an electrostatic neutralization of Bows 12 and the generation of the air cushion described above exactly at the place where these effects necessarily must be present.

It must be ensured in all circumstances that the Housing 60 receives no electrically conductive connections. On too the side of the air outlet, ie outside the housing 60 in the area the outlet openings 66, it is essential to ensure that the exiting deionizing air in the region of the outlet opening 66 and in further course of the blowing direction under no circumstances with electrically conductive Components, otherwise it would be immediately neutralized.

The stack tray 50 is bounded below by a bottom 52, are piled on the sheets 12 to form the stack 14 and by a mechanism, not shown in the vertical direction is mounted movable according to double arrow C. During the formation of the Stack 14 must control the lowering of the bottom 52 so be that the stack 14 with the respective uppermost bow 12th and thus its resulting top always at the height the outlet openings 66 and in particular between the upper and lower outlet openings 66 is to a functional training the air cushion through the emerging from the outlet openings 66 to achieve deionizing compressed air.

Finally, as Fig. 4 reveals is in the lower part of the Stack tray 50, a squeegee 80 disposed with the vacuum effect disturbing air between the leaves 12 of the stack 14 in the illustrated Siphoned off embodiment in the lower region.

Claims (19)

Apparatus for processing a multilayer electrostatically chargeable web, comprising at least one cutting device (2) for cutting the multilayer web (10) into corresponding superimposed arcs (12), an electrostatic charging device (30) for electrostatically charging the multilayer web (10) and upstream in front of the cutting device (2) located first and a downstream of the cutting device (2) located second conveyor device (20) for transporting the multilayer material web (10, 12),
characterized in that the electrostatic charging device (30) in the region of the first or the second conveying device (20) adjacent to the cutting device (2) is arranged. Device according to claim,
characterized in that the electrostatic charging device (30) is arranged substantially between the cutting device (2) and the first or the second conveying device (20). Apparatus according to claim 1 or 2, wherein the second conveyor (20) comprises an endlessly circulating conveyor belt arrangement (26).
characterized in that the endlessly circulating conveyor belt arrangement consists only of one or more subbands (26) on which or which the multilayer material web (12) rests. Device according to at least one of the preceding claims,
characterized in that the second conveyor (20) comprises a suction device (40). Device according to claims 3 and 4,
characterized in that an upper run (26a) of the conveyor belt assembly (26) passes above the suction device (40). Apparatus according to claim 5, wherein the suction device (40) has a suction surface (42),
characterized in that an upper run (26a) of the conveyor belt assembly (26) rests on the suction surface (42). Apparatus according to claim 5 or 6,
characterized in that at least one sub-band (26) is perforated. Device according to at least one of the preceding claims,
characterized in that the electrostatic charging device (30) is an ionizing device for ionizing the multilayer material web (10). Device according to at least one of the preceding claims,
characterized in that the cutting device (2) comprises a cross cutter. Apparatus for processing a multilayer electrostatically chargeable material web into individual superimposed sheets (12), in particular according to at least one of the preceding claims, with a conveying device for transporting the sheets (12), an electrostatic discharge device (70) for electrostatically discharging the sheets (12) and a stack tray (50) located downstream of the conveyor for forming stacks (14) of the superimposed sheets (12),
characterized in that the electrostatic discharge device (70) in the region of the stack tray (50) is arranged. Device according to claim 10,
characterized in that the electrostatic discharge device (70) is disposed in the upstream portion, preferably on the upstream side, of the stack tray (50). Device according to claim 10 or 11,
characterized in that the electrostatic discharge device comprises a compressed air device for generating compressed air, means (70) for electrostatically charging the compressed air with respect to the sheets (12) of opposite polarity and a blowing device (66) for blowing this air against the sheets (12) , Device according to claim 12,
characterized in that the blowing device blows the air substantially against the trailing edges (12a) of the sheets (12). Device according to claim 12 or 13,
characterized in that the blowing device comprises a nozzle arrangement (66). Device according to at least one of claims 10 to 14,
characterized in that the electrostatic discharge device (70) in a housing (60) is seated, whose one portion (64) limits the Stapelablage (50) and preferably forms a stop for the stack (14). Device according to at least one of claims 12 to 14 and according to claim 15,
characterized in that the portion (64) of the housing (60) delimiting the stacking tray (50) comprises the blowing device (66). Device according to claims 14 and 16,
characterized in that the portion (64) of the housing (60) delimiting the stack tray (50) is provided with openings (66) for the blowing out of the air. Device according to at least one of claims 10 to 17,
characterized in that the electrostatic discharge device (70) is a deionization device for deionizing the sheets. Apparatus according to at least one of claims 10 to 18, characterized by suction means (80) in the lower portion of the stack tray (50).

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