EP1462240A2 - Method of applying a reinforcing bands to a film - Google Patents

Abstract

The reinforcement application process applies double-layer reinforcement strips (3) to a sealable foil web being transported in timed strokes. V-shaped loops are formed on spaced-out sectors of the foil web (1). A controlled auxiliary loop (27) is allocated to each foil web sector on which a loop is formed.

Description

The invention relates to a method for attaching double-layer stiffening strips to a cyclically transported sealable film web, in which on predetermined, in Transport direction spaced film web sections formed V-shaped loops and the Loops forming legs are sealed together so that the emerging, transverse to the direction of the stiffening strips like a collar from the Stick out the film.

According to an article in the Packaging Strategies magazine dated November 30, 2002, there are new types Packaging bags with the name EDGE STAND become known, which are made from a sealable film web were produced and at the bottom area with a circumferential Stiffening strips are provided. This stiffening strip makes it possible for the Packaging bags placed on a flat surface and even stacked if necessary can be. The stiffening strip is folded onto the bag and has two layers. The magazine article does not provide any information on the type of manufacture, but the applicant is the present invention, the method practiced for this by obvious prior use known. The double-layer stiffening strip is folded onto the film web here along a flat transport path, along which the for carrying out the method required functional elements to a predetermined format of the to be manufactured Packaging bags are adjusted. For products with other formats, especially with other distances between the film web sections to be folded is a complex Retrofitting of the functional elements required.

The invention is based on the object in a method of the type described above to avoid a time-consuming changeover.

The object is achieved in that each film web section, on which a loop is formed, a controlled additional loop is assigned to adapt to Format changes in terms of the spacing of the film web sections is used.

Such an additional loop can be very easily attached to the film web Control halftone marks, such as recesses or print marks, thereby automatically very quick changeover with format changes is possible. This can even be done if necessary happen continuously, which makes it possible in a special case, the most varied Process formats on one and the same film web. Such an additional loop does it in addition, an additional fine-tuning as tolerance-related length compensation to ensure by automatically compensating for short length fluctuations immediately.

The additional loop is advantageous during the transport of the film web several cycle steps maintained long. As a result, it can be explained in more detail later, using the description of the figures the process is accelerated overall by shortening the cycle times. The Additional loops can be maintained by connecting them to a means of transport, which ensures a secure fixation. This even makes it possible to have a plurality of additional loops at the same time, according to the successive ones Process steps.

If the procedure is ready for very fluctuating format changes, then let if necessary, split the additional loop into two partial loops.

The invention also describes an apparatus for performing the method with which the Loop-forming folding sword, with two each associated with the folding sword, the film web immediately before and after a pair of clamping jaws, one with the legs the loops pressing together, with one of the pressing device assigned heating device and clocked with a folding sword assigned driven transport roller. For such a device, the invention provides that the transport roller is a drum of relatively large diameter along its circumference arranged means for forming a plurality of loops and additional loops.

Such a drum not only makes it possible to use the method for different formats perform the film webs, but also saves a lot of time by the Circumference of the drum passes a plurality of switching stations. In preferred An embodiment of the invention provides that the pressing device has two for each loop the drum encircling, relatively movable press jaws, each at the same time form one jaw for the two pairs of jaws, the other jaws outside the drum, but this is deliverable, is arranged.

The arrangement of the press jaws mentioned makes it possible in a simple manner, in each case generated stiffening strips in the transport direction of the film web either collar-like to protrude in front or back. To achieve this, the press jaws are on their area forming the respective jaws of different diameters Drum assigned. If, for example, as later based on the description of the figures can be seen, the first pressing jaws in the transport direction the smaller outer diameter then the stiffening strip protrudes forward like a collar. In the opposite case when the first pressing jaw in the transport direction has the larger outside diameter the stiffening strip backwards like a collar.

The use of the aforementioned drum makes it possible for all rotating Pressing devices a common folding sword arranged outside the drum Forming the loops is associated. Likewise, all additional loops can be one common, arranged outside the drum format roller. The Functional elements for the immediate formation of the loops and the additional loops are thus only available once, while the pressing devices for sealing the loops together, distributed over the circumference of the drum, exist several times.

The drum is expediently provided with a sector assigned to a plurality of pressing devices Heaters assigned. This allows the legs to be sealed together Distribute loops to several stations so that the cycle time is different for each individual cycle step can be reduced. This cycle time can be reduced even further if the Sector assigned to heaters is subordinated to a sector with coolants.

Further advantages and features of the invention result from the following description some schematically illustrated embodiments.

Figur 1 eine siegelfähige Folienbahn mit vormarkierten Folienabschnitten, an denen die doppellagigen, kragenartig abstehenden Versteifungsstreifen gebildet werden sollen,

Figur 2 die Folienbahn der Figur 1, nachdem solche Versteifungsstreifen gebildet wurden,

Figur 3 eine Ansicht in Richtung des Pfeiles III der Figur 2 zur Demonstration der kragenartig abstehenden Versteifungsstreifen,

Figur 4 in stark vergrößerter Darstellung eine dem Bilden eines Versteifungsstreifens dienende V-förmige Schlaufe, deren Schenkel aneinandergesiegelt werden sollen,

Figur 5 einen Ausschnitt eines perspektivisch dargestellten Verpackungsbeutels, an welchem ein Versteifungsstreifen zu einem steifen stapelfähigen Rand geformt wurde,

Figur 6 in sehr schematischer Darstellung eine Vorrichtung zum Durchführen des Verfahrens zum Anbringen von Versteifungsstreifen an einer siegelfähigen Folienbahn, mit einer erfindungsgemäßen Transporttrommel,

Figur 7 in vergrößerter Darstellung einen Ausschnitt aus Figur 6 im Bereich eines Falzschwertes und einer einer Schlaufe zugeordneten Presseinrichtung,

Figur 8 einen mit der Presseinrichtung der Figur 7 erzeugbaren, nach hinten abstehenden Versteifungsstreifen,

Figur 9, als Abwicklung des Umfanges der Trommel dargestellt, eine Ausführung mit mehreren Zusatzschlaufen.

Show it:

FIG. 1 shows a sealable film web with pre-marked film sections on which the double-layer, collar-like stiffening strips are to be formed,

FIG. 2 shows the film web of FIG. 1 after such stiffening strips have been formed,

FIG. 3 shows a view in the direction of arrow III of FIG. 2 to demonstrate the stiffening strips protruding like a collar,

FIG. 4 shows a greatly enlarged illustration of a V-shaped loop used to form a stiffening strip, the legs of which are to be sealed together,

FIG. 5 shows a section of a packaging bag shown in perspective, on which a stiffening strip was formed into a rigid stackable edge,

6 shows a very schematic representation of a device for carrying out the method for applying stiffening strips on a sealable film web, with a transport drum according to the invention,

FIG. 7 shows an enlarged view of a detail from FIG. 6 in the area of a folding sword and a pressing device assigned to a loop,

FIG. 8 shows a stiffening strip projecting to the rear with the pressing device of FIG. 7,

Figure 9, shown as a development of the circumference of the drum, an embodiment with several additional loops.

With reference to Figures 1 to 4, the basic method is first in general form shown, which also includes the prior art.

According to Figure 1, a sealable film web 1 in the transport direction A is not yet here machine system shown transported. At clear intervals x from each other are on this Film web 1 relatively narrow film web sections 2 running transversely to film web 1 provided that are only indicated by dash-dotted lines in Figure 1. These film web sections 2 can be recognized, for example, on the film web 1 only by the fact that it is certain color printing are marked. At these film web sections 2 according to Figures 2 and 3 stiffening strips 3 produced in a manner to be described later. The respective center of a film web section 2 can on both edges of the film web 1 by so mentioned raster marks 4, for example by narrow recesses or as print marks.

It should already be indicated here that in addition to the width of a film web 1, the distance x two Foil sheet sections 2 can be quite variable, depending on the type of later from the Foil web 1 to be manufactured bag-like product.

So-called stiffening strips 3 according to FIGS. 2 and 3 are used for the later product provided, which run transversely to the transport direction A and collar-like from the film web 1 protrude. Such a stiffening strip 3 is formed by forming a V-shaped loop 5 formed, as can be seen from the enlarged figure 4. Such a loop 5 contains two legs 6 and 7, which are sealed together when performing the method and then form a double-layer stiffening strip 3, which - depending on certain details the manufacture - can be inclined forward or backward in the direction of transport A.

In Figure 5, a section of a packaging bag 8 is shown in perspective, which with the immediate invention has nothing to do, but which is stiff in the floor area includes peripheral edge 9, for which the stiffening strip 3 described is provided. The rigid edge 9 is used in the later packaging bag 8, for example, for stacking a flat surface. This rigid edge 9 was exclusively from the film web sections 2 formed.

A device according to the invention for performing the The inventive method for producing the stiffening strips 3 explained.

A sealable film web 1 can be seen, which shows the device in transport direction A. runs through, with only a few already mentioned in the left area of the drawing Raster marks 4 can be seen, while in the right area there are already some stiffening strips 3 have arisen.

The device contains a transport roller, which as a drum 10 of relatively large diameter is trained. The drum 10 is driven clocked in the direction of rotation B. The individual bars are indicated by dash-dotted ray-like diameter lines.

In addition to the drum 10, there is an upstream driven delivery roller pair 11 and downstream driven delivery roller pair 12. In addition, deflection rollers 13, 14, 15 and 16 available. Between the pair of delivery rollers 11 and a deflection roller 13 is one Dancer roller 17, a dancer roller between the deflection roller 16 and the pair of delivery rollers 12 18 provided. The dancer rollers 17 and 18 are used to control the sag in a known manner the film web 1, since the delivery roller pairs 11 and 12 are continuous, but the drum 10 clocked is driven.

The drum 10 contains along its circumference part of that for carrying out the method required functional elements, while another part of the functional elements of the drum 10 assigned, but is arranged outside the same. With the small letters a to h the individual switching stations are indicated at which the drum 10 rotates in Direction of rotation B stops for a fraction of a second.

Along the circumference of the drum 10 there are a total of eight rotating press devices 19 provided, one of which is shown in somewhat more detail at station a. each Press device 19 contains a fixed press jaw 20 and a movable one relative to it Press jaws 21. The movable press jaws 21 are located at stations a, g and h, respectively in its position moved away from the fixed press jaws 20, while at the other stations b until f the respective pressing device 19 is closed.

A folding blade 22, which is located outside the drum 10, is assigned to the station a controlled in the direction of the double arrow is movable. It is therefore only a single folding sword 22 available for the drum 10.

Station a also includes pairs of jaws 23 and 24, each of which is already one of the mentioned press jaws 20 and 21 and a movable outside of the drum 10 arranged jaws 25, 26 exist. The formed by the press jaws 20 and 21 Jaws therefore rotate around the drum 10, while those outside the drum 10 located jaws 25 and 26 each according to the direction of the double arrow Press jaws 20 and 21 are deliverable or can be removed therefrom and thereby temporarily the mentioned Form jaw pairs 23 and 24.

At station a there is finally a so-called format roller 28, which is in the direction of Double arrow is controllable, namely by scanning the raster marks 4. The Format roller 28 creates an additional loop 27 on the circumference of the drum 10, which the Stiffening strips 3 forming loop 5 is assigned and which during one circulation of the Drum 10 is retained, even if the format roller 28 immediately after forming the

Additional loop 27 pulls back from the circumference of the drum 10. The additional loop 27 is in Dependence on the distances x of the film web sections 2 formed, with larger distance x the additional loop 27 also becomes larger.

The attachment of these additional loops 27 makes the device independent of the format, so that one and the same drum 10 without retooling the other functional elements with webs 1 different distances x of the film web sections 2 can be processed.

The process sequence at the individual switching stations a to h is now described below, especially at switch station a, because a large part of the process steps are carried out there becomes.

At the switching station a, the folding blade 22 is first between the press jaws 20 and 21 of the opened press device 19 retracted and thereby formed a loop 5. Nearly at the same time, only insignificantly thereafter, the format roller 28 is fed, resulting in a Additional loop 27 forms which is assigned to the loop 5. To fix this state the jaws 25 and 26 are delivered to the press jaws 20 and 21. This allows both the folding blade 22 and the format roller 28 again from the circumference of the drum 10 be withdrawn. In this state, the jaws 25 are on the press jaws 20 and the jaws 26 on the press jaws 21. Now the press jaw 21 is the Press jaws 20 are delivered, whereby the legs 6 and 7 of the loop 5 are pressed tightly against one another, however not yet be sealed. Because the pressing device 19 is now closed, can the jaws 25 and 26 of the jaw pairs 23 and 24 loosen again.

In this state, which marks the end of the cycle at the switching station a, is the Loop 5 clamped in the press device 19, while the additional loop 27 is practical is left up to you, but this does not bother you, because the film 1 is already on the previous switch station b had been clamped in the same way.

The press devices 19 remain during the clocked rotation in the direction of rotation B. closed and are only opened at switchgear g. Between two each Pressing devices 19 have a freely sagging additional loop 27.

In Figure 6, a sector I is identified by a circular double arrow. In this sector I, which is located between the switching stations b and e, the pressing devices 19 can be heated by a heating device, not shown. The pressed loops 5 are thus heated in stages when the drum 10 is advanced, whereby the legs 6 and 7 of each loop 5 are sealed together. Then there is a sector II , which is located between the switching stations e and g and in which the sealed loops 5 are cooled so that the clocked work process can run faster overall.

The process, in particular the formation of the additional loops 27, is controlled by a sensor 29, which preferably scans the edges of the film web 1 and depending on the position of the raster marks 4 controls the format roller 28 with regard to its stroke.

The design of the device described here makes it possible for everyone Foil web section 2, on which a loop 5 is formed, a controlled additional loop 27 to assign, which the adaptation to format changes with respect to the distances x the Foil sheet sections 2 is used. The additional loop 27 is the grid marks 4 of the Controlled film web 1. An additional loop 27 remains during the transport of the film web 1 Maintained along the circumference of the drum 10 for several cycle steps by Clamping on the individual pressing devices 19. As can be seen, there will be a plurality of loops 5 and additional loops 27 maintained at the same time.

It could be seen from FIG. 6 that the movable pressing jaws 21 were smaller Have outer diameters than the fixed jaws 20. In such a Arrangement of the pressing device 19, the stiffening strips 3 formed with respect to the Film web 1 aligned in transport direction A.

Should it be desirable that the individual compression strips 3 against the Transport direction A should protrude from the film web 1 like a collar to the rear, then the Press device 19 according to FIG. 7. It can be seen that with this variant the in Transport direction A first and fixed press jaws 20 has a larger outer diameter than the following movable press jaws 21. This creates during pressing and later Sealing the loop 5 stiffening strips 3, which according to FIG stick out to the back.

FIG. 9 shows a detail from FIG. 6 with the special feature that the in Figure 6 additional loops 27 shown in Figure 9 divided into two sub-loops 30 and 31 are. This configuration is expedient if on the same drum 10 particularly large format changes with regard to the distance x have to be managed. It can then it makes sense to provide several additional loops 30 and 31 for a loop 5, which a format roller 32 and 33 is assigned.

In FIG. 9 it can also be seen that the pressing jaws 21 and 20 each have an outer diameter Have areas 34 and 35, which according to the description of Figure 6 at the switching station a the clamping jaws 25 and 26, not shown in FIG. 9, are deliverable.

Claims (14)

Method for attaching double-layer stiffening strips (3) to a sealable film web (1) transported in a clocked manner, in which V-shaped loops (5) are formed on predeterminable film web sections (2) spaced apart in the transport direction (A) and which form the loops (5) Legs (6, 7) are sealed to one another in such a way that the resulting stiffening strips (3) extending transversely to the transport direction (A) project from the film web (1) in a collar-like manner, characterized in that each film web section (2) on which a loop ( 5) is formed, a controlled additional loop (27) is assigned, which is used to adapt to format changes with regard to the spacing (x) of the film web sections (2). A method according to claim 1, characterized in that the additional loop (27) is controlled by raster marks (4) or the like of the film web (1). Method according to Claim 1 or 2, characterized in that the additional loop (27) is maintained for several cycle steps during the transport of the film web (1). A method according to claim 3, characterized in that the additional loop (27) is maintained by clamping on a means of transport. A method according to claim 4, characterized in that a plurality of additional loops (27) is maintained at the same time. Method according to one of claims 1 to 6, characterized in that the additional loop (27) is divided into two partial loops (30, 31). Device for carrying out the method according to one of the preceding claims, with a folding sword (22) forming the loops (5), with two pairs of clamping jaws associated with the folding sword (22) and clamping the film web (1) immediately before and after a loop (5) (23, 24), with a pressing device (19) pressing the legs (6, 7) of the loops (5) together, with a heating device assigned to the pressing device (19) and with a clocked driven transport roller assigned to the folding blade (22), thereby characterized in that the transport roller is a drum (10) of relatively large diameter with devices arranged along its circumference for forming a plurality of loops (5) and additional loops (27). Apparatus according to claim 7, characterized in that the pressing device (19) for each loop (5) contains two pressing jaws (20, 21) which rotate around the drum (10) and are movable relative to one another and which each have a clamping jaw for the two pairs of jaws ( 23, 24) form, whose other clamping jaws (25, 26) are arranged outside the drum (10), which can be delivered. Apparatus according to claim 8, characterized in that the pressing jaws (20, 21) are assigned to different diameters of the drum (10) at their region (34, 35) forming the respective clamping jaws. Device according to one of claims 7 to 9, characterized in that all pressing devices (19) are assigned a common folding sword (22) arranged outside the drum (10). Device according to one of claims 7 to 10, characterized in that all additional loops (27) are assigned a common format roller (28) arranged outside the drum (10). Device according to one of claims 7 to 11, characterized in that the drum (10) is assigned a sector (I) with heating devices which is assigned to a plurality of pressing devices (19). Apparatus according to claim 12, characterized in that the sector (I) assigned to the heating devices is followed by a sector (II) with coolants. Device according to one of claims 7 to 13, characterized in that the drum (10) is assigned at least one sensor (29) for scanning the raster marks (4) of the film web (1).

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