ES2443227T3 - Background cover sheet application set for borderless gluing - Google Patents

Abstract

Device for gluing pieces of material (1) onto parts of bags (2) or bags, comprising: - a supply device, by means of which adjacent pieces of material can be supplied, - a separation device, by which individual pieces of material can be supplied, - a first transport cylinder, with which the separated pieces of material can be subsequently transported, - an adhesive application device (19), with which adhesive can be applied to each respective material part , in which a second transport cylinder (6) is provided with which the pieces of material can be collected from the first transport cylinder and with which the pieces of material can be applied on the parts of the bags (2) or sacks , and in which the adhesive application device (19) cooperates with the second transport cylinder (6), so that the adhesive can be applied on the piece of material when this is on the second transport cylinder (6), characterized in that the second transport cylinder (6) comprises at least one piece of format (17) whose surface contour corresponds to the area of a piece of material that is to be provided of adhesive, and why the piece of material rests on this piece of format during transport with the second transport cylinder (6).

Description

Background cover sheet application set for borderless gluing

The invention relates to a device for gluing pieces of material onto pieces of bags or sacks according to the preamble of claim 1, as well as to a corresponding method according to the preamble of claim 12.

Such devices and procedures have been used for many years in the manufacture of bags or sacks. The bags, in particular the square bottom bags with side folds, are often manufactured in a longitudinal process, in which for the processing of the bag a piece of tube is transported in its longitudinal direction. A bottom, often a block or square shaped bottom, is formed at the end of the tube piece that marches ahead. The publication for call to oppositions of German patent application DE 1245 699 shows a complete device for the manufacture of bags from band-shaped materials. Often such bags are provided with bottom cover sheets to increase the stability of the bottom. At the same time the bottom cover sheets can be made so that the user of these bags has a handle. Such bags with cover sheets made in different ways are represented and described in DE 41 02 548.

Document DE 1 245 699 shows a device for gluing pieces of material onto parts of bags or sacks. The device is called a cover sheet glue device there. However, in the mentioned document it is not described in detail.

Such a device for gluing pieces of material first comprises a supply device for the supply of pieces of material. This can be a charger with which the individual pieces of material, that is for example cover sheets, can be supplied as batteries. Often there are, however, rolls of material band from which individual pieces can be separated. This is done in a separation device in which the individual pieces of material can be separated from the roll. Such separation devices almost always comprise a clean edge or perforation cutting blade with which separation cuts can be produced in the web of material. In the case of stacked individual pieces of material the separation device is designed so that it can remove a piece of material from the stack. The separate piece of material is collected by a first transport cylinder that leads to the piece of material in front of an adhesive application device. The piece of material provided with adhesive can then be glued on pieces of bags or sacks, generally the bottoms.

The adhesive application device also comprises an adhesive reservoir and an adhesive removal roller that removes the adhesive from the adhesive reservoir. The mentioned roller then transfers the adhesive to an adhesive application roller. This roller has a piece of format corresponding to the surface of the piece of material that is going to be glued, which is often also called a cliche. Only this piece of format picks up the adhesive from the adhesive removal roller and transfers it to the piece of material.

Since the cutting blade provided for separation is often integrated in the transport cylinder, the problem of fouling by the adhesive results.

Document BE 489 863 A discloses a device, in which unlike the previous one

- a second transport cylinder (6) is provided with which the pieces of material can be collected

of the first transport cylinder and with which the pieces of material can be applied on the parts

of the bags (2) or sacks, and

- the adhesive application device (19) cooperates with the second transport cylinder (6), so

that the adhesive can be applied on the piece of material when it is on the second

transport cylinder (6).

For the provision of adhesive and the application of the piece of material on the bags or sacks, a second transport cylinder is thus provided that collects the piece of material from the first transport cylinder. Only then the piece of material is provided with adhesive. This prevents an unexpected transfer of adhesive on the first transport cylinder and with it on the cutting blade or other separation devices.

However, it was found that it is not possible de facto to provide the piece of material for the entire adhesive surface in the prior art devices. If the cliché really corresponds exactly to the contour of the piece of material that is going to be glued, then due to the necessary tightening pressure the adhesive comes out from the edges of the piece of material, which leads to fouling problems mentioned. A reduction of the cliché that fits very well to avoid this problem is not possible or it is only very complicated.

The object of the present invention is to propose a device and a method for gluing pieces of material onto parts of bags or sacks that avoid the aforementioned inconveniences and also others.

According to the invention this object is carried out by adding the feature of the preamble of claims 1 and

12.

According to the invention it is provided that the second format cylinder includes a format piece whose surface contour corresponds to the area of a piece of material to be provided with adhesive and that the piece of material rests on this format piece during transport with the second transport cylinder.

The problem described is avoided with the invention, since the piece of material is now arranged high with respect to the outer surface by the format piece on the outer surface of the second transport cylinder. If the adhesive is now applied by means of a roller, then it can only be attached to the piece of material and does not reach the second transport cylinder. This prevents fouling of the transport cylinder on the one hand and, on the other hand, a complete adhesive application, called flush, is achieved. Especially important is the last mentioned point when the bag must be automatically filled in a filling device. In the case of bags made of conventional devices there is often an edge on the bottom cover sheet that is not attached to the bag or bag. This edge can be deployed in a filling device and then obstruct the correct transport of the bag through such device. In such cases, machine interruptions cannot be ruled out. With the device according to the invention, bags or sacks can now be produced that can be safely transported to the filling devices.

In another advantageous embodiment of the invention it is provided that the format part comprises recesses or depressions. This embodiment is advantageous when the cover sheet must include one or more handles. Such handles can be generated by providing the piece with cutting material, so that the subsequent user can grab through the area limited by the cuts. Naturally, no adhesive should be applied to these areas. With the recess or depressions in the format piece the area of the subsequent handles can now be pulled a little inwards, seen in the radial direction of the second transport cylinder, so that this area is not provided with adhesive.

The piece of material can be held on the surface of the second transport cylinder in different ways. A feasible solution would be clamps or other devices that act mechanically. Magnetic or electrostatic forces would also be possible depending on the material. However, it is preferable that the second transport cylinder comprises holes to which negative pressure can be applied. This negative pressure is sufficient to be able to hold the material pieces of very different materials on the cylinder. It can also be provided that not only negative pressure, but also overpressure, can be applied to the holes. The piece of material can thus be aspirated with negative pressure or repelled with overpressure. The latter is advantageous at the moment when the piece of material is transferred from the second transport cylinder and must be applied on the bag.

It is advantageous that at least a part of the holes is extended through the formatting piece, so that a piece of material can also be held securely on the formatting piece.

When the second transport cylinder has a format piece, a cliché no longer has to be applied to the adhesive application cylinder itself. Just use an adhesive application roller that has the same surface structure across the entire outer contour. Thus, in particular it can be smooth. It is also advantageous that the adhesive application roller comprises at least certain regions of a metal surface.

In a preferred embodiment, an adhesive application device is provided with which hot melt adhesive can be supplied, this is meltable adhesive. In addition to the technical advantages of the procedure (it is not feared that the adhesive will dry in the operating breaks, a long drying time is not necessary for the work pieces glued together) it should be mentioned as an advantage that now they can no longer be glued only paper materials. Now plastic bags can be manufactured in the same way. Even bags comprising both paper and plastic can be produced. In general with this, bags of discretionary materials can be manufactured.

In an advantageous embodiment of the invention the adhesive application device by means of a withdrawal device can be removed from an operating position, in which the adhesive can be applied on the piece of material, so that contact with the piece of material or, if it is missing, with the piece of format. In this way the unexpected fouling of the transport cylinder can be avoided. The withdrawal device can thus comprise at least one cylinder of compressed air. Advantageously they are two cylinders of this type. A first short stroke cylinder can deal with a very rapid removal of the adhesive application device when a piece of material does not arrive. The withdrawal path only has to be a few millimeters. A long stroke cylinder can transport the adhesive application device to a waiting position that can be found, for example, about 10 cm above the operating position. Compressed air cylinders are an example of applicable lifting devices. Other devices can also be used.

Especially advantageous is a sensor with which the presence or absence of a portion of material can be determined. The sensor can provide its "observations" to a control device that, in the absence of a piece of material, activates the withdrawal device.

In another embodiment of the invention it is provided that the adhesive application device comprises an adjustment device with which the minimum radial position relative to the second transport cylinder can be adjusted. By the optimum adjustment of the adhesive application roller with respect to the second transport cylinder, the transfer of adhesive can be optimized, so that no adhesive reaches the formatting part or the second transport cylinder. In addition, the amount of adhesive to be transferred to the piece of material can be adjusted.

Other embodiments of the invention are deduced from the specific description and the claims.

The individual figures show:

Fig. 1,

a side elevation of a device according to the invention for bonding pieces of material,

Fig. 2,

a view of section II-II in Fig. 1,

Fig. 3,

a view of section III-III in Fig. 2, and

Fig. 4,

a view of section IV-IV in Fig. 2.

Figure 1 shows a device 1 for gluing pieces of material not shown in detail on parts of bags 2. The bags are also transported by means of a so-called tank cylinder 3 which has the function of depositing a bag 2 already prepared itself on A stack of bags not shown. The bag 2 is transported by the reservoir cylinder firstly along a first compressor roller 4. This has the function of compressing again the bottom 5 of the bag that has just been shaped in the preceding work steps to achieve on the glue of the piece of material (here: a bottom cover sheet) a bottom as flat as possible. Directly below, the bottom cover sheet supplied by the second transport cylinder 6 and already provided with adhesive is precisely applied on this bottom. The second transport cylinder may also be referred to as a transfer cylinder 6. The work steps that are necessary for the supply of the bottom cover sheet will be described later. After application of the bottom cover sheet, the bag 2 is driven in front of a second pressure cylinder 7 that compresses the bottom again, so that the bottom cover sheet is as solidly as possible attached to the bottom.

The bottom cover sheets are supplied in the form of a roll 8 of which the material web is wound

9. The band 9 passes through the opening between rollers of a die cutter 10. A first roller 11 also carries one or more die cutter blades, a second roller 12 comprises an opposite position. With this die cutter, cuts in the web of material 9 can be produced that subsequently separate the handles from the rest of the bottom cover sheet.

The band 9 now passes through the opening between rollers of a pair of feed rollers 13. The band 9 then reaches the contour surface of a cutting cylinder 14, which carries a separating blade 15, as a rule in the form of clean cutting blade. The blade 15 cooperates with the fixed opposite blade 16 and separates individual pieces of material, the subsequent bottom cover sheets, from the strip of material 9. The cutting cylinder continues with the transport of the bottom cover sheets thus separated and therefore it can also be called the first transport cylinder 14. In order to retain the bottom cover sheet on the outer contour of the cutting cylinder 14, this is preferably made as a suction cylinder. This means that this cylinder comprises on its contour surface holes to which a negative pressure can be applied. The structure of the cutting cylinder 14 will then be explained based on the transfer cylinder 6 which advantageously has the same functionality with respect to the fastening of the bottom cover sheet.

The cutting cylinder 14 transfers the separate bottom cover sheet to the transfer cylinder 6. For this purpose, negative pressure is applied to the holes to those previously applied, so that the corresponding area of the cover sheet of bottom is pressed by the cutting cylinder 14 outward in the direction of the transfer cylinder 6. At the same time a negative pressure is applied to the transfer cylinder, so that a secure transfer of the bottom cover sheet occurs.

The transfer cylinder 6 carries on its outer surface at least one piece of format 17. This is replaceable and corresponds to the extension of the bottom cover sheet. The bottom cover sheet after its capture by the cutting cylinder occupies exactly the part of format 17. The piece of format 17 has perforations that correspond to the holes of the transfer cylinder 6 to which negative pressure can be applied , so that by the negative pressure a bottom cover sheet can be safely fixed to the format part 17. In the following course the bottom cover sheet is compressed by a pressure roller 18 against the format part 17 , so that not only the bottom cover sheet is reattached on the formatted piece 17 and smoothed, but that the rear handle strip is pressed a little in a depression introduced into the formatted piece. The depression of the format piece and the maintenance of the handle strip will be discussed

later in more detail. Now only areas of the bottom cover sheet, which do not belong to the rear handle strip, remain in an exposed position, so that only these areas are provided with adhesive. For this purpose, an adhesive application device 19 is provided comprising at least one glue tank 20 and an adhesive application roller 21. The adhesive application roller 21 can also remove the adhesive directly from the container. But an adhesive transfer roller can also be provided, as is known, which assumes the function of adhesive removal and applies the adhesive on the adhesive application roller. The adhesive application roller 21 is positioned relative to the transfer cylinder so that it precisely touches the parts of the bottom cover sheet that rest on the raised areas of the format part 17 and only provides adhesive to these parts. Therefore, neither the contour surface of the transfer cylinder 6 nor the deeper located areas of the bottom cover sheet are adhesive-coated, this is in particular the rear handle strips. Since on the contrary the adhesive application roller 21 rolls on the exposed areas of the bottom cover sheet, the bottom cover sheet that is not in an uncovered area is provided with adhesive. For the adaptation of the position of the adhesive application roller 21 this can preferably be provided movable in the direction of the double arrow 22 together with the adhesive container.

In the transfer of the bottom cover sheet the negative pressure acting on the holes is disconnected and an overpressure is connected, so that the adhesion of the bottom cover sheet to the bag 2 is still favored.

It may happen that a bottom cover sheet is not transferred from the cutting cylinder 14 to the transfer cylinder 6 or at least not correctly. In order to prevent the adhesive application roller 21 from coming into contact with the format part 17, a sensor 23 that detects the presence or absence of a bottom cover sheet is provided. The corresponding signals can now be processed by a control device (not shown). This can now cause a displacement of the adhesive application roller 21 in the direction of the double arrow 22. The displacement is carried out by means of a withdrawal device which will be explained by virtue of Figure 2.

In figure 2, which shows the view II-II of figure 1, several more peculiarities of the device are shown

1. In this figure it can be recognized that the adhesive reservoir 21 is movable along a rail 24 in the direction of the double arrow 22. Several rails arranged parallel can also be provided. Preferably at each end of the adhesive tank 21 two rails are arranged. The rails 24 are supported on consoles 25 that can be attached to the machine frame in a manner not shown. A stop 26 is further supported on a console 25. This is adjustable so that the operating position, in which the adhesive application roller 21 applies the adhesive on the bottom cover sheet is variable. As an example for a stop 26 there is shown a pin 50 which is provided with a sector 51 with a hexagonal plant, to which a screw wrench and a sector 52 can be applied with a thread that is screwed to the console 25. By turning the pin you can its height varied and with it the operating position.

On the console 25 a first piston cylinder unit 26 is also supported, which is made as a rapid lifting cylinder unit. This is activated by the control device if the absence of a bottom cover sheet was detected with the help of sensor 23. In addition, a second piston cylinder unit 27 is arranged on the console 25 which is made as a long-stroke cylinder unit. With this cylinder unit 27 it is possible to move the adhesive application device 19 to a waiting position.

In figure 2 the outer surface 31 of the transfer cylinder 6 is shown. It can be recognized that it comprises several holes 30. In order to be able to apply negative pressure or overpressure to these, at least one disc is arranged on a front face of the transfer cylinder 6 32 which does not rotate together with the transfer cylinder. This disc 32 comprises an overpressure connection 33 and a negative pressure connection 34. Overpressure and negative pressure mean in this context that a fluid that is subjected to greater or lesser pressure relative to the ambient pressure is provided. The preferred fluid is air, so that in case of overpressure, one can speak of compressed air and in case of negative pressure of a vacuum.

Figure 3 shows essential features that are necessary to apply negative pressure or overpressure to the holes 30. The transfer cylinder 6 has a relatively thick cover comprising several axial perforations 35 which in turn can be made as through holes. Each of these axial perforations 35 can communicate with several radial perforations 30 representing the holes 30. If no negative pressure or overpressure is now applied to the individual holes 30, bolts 37 can be introduced into the corresponding axial perforations 35 whose length has a dimension such that the desired number of holes 30 is covered. In Fig. 3 the open perforations 35 are shown in white and in black the perforations closed with the bolts 37.

In Figure 4 the disk 32 is shown in detail. This comprises a depression 38 in the form of a circle arc that is connected to a vacuum connection. The radial position of the depression 38 has such a dimension that it can come into contact with the perforations 35. The depression 38 comprises for example an angle in a range of 200 to 270 degrees. To a perforation 35, which is in this angular range, negative pressure is applied. In another rotation of the transfer cylinder 6 the perforation 35 leaves after a certain time the depression 38.

Shortly after the perforation 35 reaches a second depression 39 in the form of a circle arc. This is supplied with overpressure through the compressed air connection 33, so that the overpressure now also reaches the perforation 35. In the manner described above, the switching of the negative pressure holes to overpressure is performed when the bottom cover sheet It no longer has to be held but repelled and must be transferred. This described procedure does not only refer to the transfer cylinder. It can also be provided in the case of cutting cylinder 14.

List of reference symbols

one

Device for bonding pieces of material

2

Bag

3

Tank cylinder

4

First pressure roller

5

Stock fund

6

Second transport cylinder / transfer cylinder

7

Second pressure roller

8

Roll

9

Material band

10

 Die cutter

eleven

 First roller

12

 Second roller

13

Pair of feed rollers

14

Cutting cylinder

fifteen

Separation blade

16

 Opposite blade

17

Format piece

18

Pressure roller

19

Adhesive application device

twenty

Adhesive tank

twenty-one

Adhesive application roller

22

Direction of movement of adhesive application roller 21

2. 3

 Sensor

24

 Rail

25

 Console

26

First piston cylinder unit

27

Second piston cylinder unit

30

 Holes

31

External surface of transfer cylinder 6

32

 Disk

33

Compressed air connection

3. 4

Vacuum connection

35

 Axial drilling

36

Spindle of transfer cylinder 6

37

 Cap screw

38

Depression with circle arc shape

39

Second depression with the shape of a circle arc

fifty

 Barrette

51

Portion with hexagonal plant

52

Thread Portion

Claims (11)

1. Device for gluing pieces of material (1) onto parts of bags (2) or bags, comprising: - a supply device, by means of which adjacent pieces of material can be supplied, - a separation device, by means of which individual pieces of material can be supplied, - a first transport cylinder, with which the separate pieces of material can be subsequently transported, - an adhesive application device (19), with which adhesive can be applied to each piece of respective material, in which a second transport cylinder (6) is provided with which the pieces of material can be collected from the first transport cylinder and with which the pieces of material can be applied on the parts of the bags (2) or bags, and in which the adhesive application device (19) cooperates with the second transport cylinder (6), so that the adhesive can be applied on the piece of material when it is on the second transport cylinder ( 6), characterized in that the second transport cylinder (6) comprises at least one piece of format (17) whose surface contour corresponds to the area of a piece of material to be provided with adhesive, and why the piece of material is supported on this format piece during transport with the second transport cylinder (6).

2.

 Device according to the preceding claim, characterized in that the format piece comprises recesses or depressions (38,39).

3.

 Device according to one of the preceding claims, characterized in that the second transport cylinder

(6) comprises holes (30) in its peripheral wall to which a negative pressure can be applied, so that the piece of material can be attached to the transport cylinder.

Four.

 Device according to one of the three preceding claims, characterized in that at least a part of the holes (30) extends through the formatting part.

5.

 Device according to one of the preceding claims, characterized in that hot melt adhesive can be supplied with the adhesive application device (19).

6.

 Device according to one of the preceding claims, characterized in that the adhesive application device (19) comprises an adhesive application roller (21) with which the adhesive can be applied on a piece of material, the application roller comprising adhesive (21) at least in certain regions a metal surface.

7.

 Device according to one of the two preceding claims, characterized in that the adhesive application device (19) by means of a withdrawal device can be removed from the second transport roller (6) from an operating position.

8.

 Device according to one of the preceding claims, characterized in that the withdrawal device comprises at least one cylinder of compressed air.

9.

 Device according to one of the preceding claims, characterized in that a sensor (23) is provided with which the presence or absence of a portion of material can be determined, so that in the absence of a portion of material the device can be actuated. withdrawal device.

10.

 Device according to one of the preceding claims, characterized in that the adhesive application device (19) comprises an adjustment device with which the minimum radial position with respect to the second transport cylinder (6) can be adjusted.

eleven.

 Procedure for gluing of pieces of material onto parts of bags (2) or bags, in which:

- contiguous pieces of material can be supplied with a delivery device, - individual pieces of material can be supplied by a separation device, - separate pieces of material can be subsequently transported by a first transport cylinder, - with an adhesive application device (19) adhesive is applied to each piece of respective material, in which the pieces of material are collected by a second transport cylinder (6) and are applied on the parts of the bags (2) or sacks, and in which with the adhesive application device (19) it can be applied adhesive on the piece of material when it is on the second transport cylinder (6), characterized in that the second transport cylinder (6) comprises at least one piece of format (17) whose surface contour corresponds to the area of a piece of material to be provided with adhesive, and because the piece of material rests on this format piece during transport with the second transport cylinder (6).