EP2499048B1 - Method and device for producing triangular packing bags - Google Patents

Description

The invention relates to a method for the production of triangular packaging bags from a film strip and an arrangement for producing such packaging bag according to this method.

Various powdery, granular, lumpy or even liquid goods are packaged in so-called tubular bag packaging in which a film strip is formed into a tube. This hose is sealed at cross seams, so that a closed packaging space for receiving the packaged goods arises. The sealed in this way film tube can be severed at the stitching optional for the formation of individual tubular bag packaging. Alternatively, instead of a separating cut, a perforation may be applied. This results in a so-called chain pack, from which the individual packaging bags can be demolished as needed.

If the sealing seams are applied transversely to the longitudinal direction of the film tube, rectangular packaging bags are created in the plan view. For certain applications, however, triangular packaging bags may also be desired in the ground plan. For this purpose, the sealing seams are arranged in a zigzag shape at a certain angle to the longitudinal axis of the film tube. According to the prior art, a film strip is first formed into a tube, wherein the longitudinal edges of the film strip are sealed together to form a longitudinal seam. Subsequently, the attachment of a diagonal seam, which intersects the longitudinal seam, the filling of the packaging bag and finally the sealing of the same by a further, also diagonal, but oppositely inclined sealing seam takes place alternately.

So that the packaged goods can fall into the bag interior, the film tube during the packaging process is perpendicular, ie parallel to the direction of gravity force guided. In this case, the diagonal sealing seams of the triangular packaging bag extend obliquely to the direction of the weight force, which makes complete filling of the packaging bag difficult or impossible. There is a risk that the packaged goods get to the sealing portion of the diagonal transverse sealing seams, whereby a dense sealing of the filled packaging is made difficult or impossible. In the plan triangular tubular bag packaging must therefore have an excess, resulting in an excessive use of film material. This fact is further complicated by the fact that further film material is consumed for the production of the longitudinal sealing seam.

Another problem is that in an individual case an incomplete or even total lack of filling is observed. Such individual, not or improperly filled packaging bags must be discarded. This is particularly important when chain packages are to be produced in which each individual packaging bag must be filled. In this case, then the entire chain pack is weed out, which can significantly increase the associated scrap costs.

The invention has for its object to provide a method by means of which in the floor plan triangular packaging bags are simple and reliable to produce and fillable.

This object is achieved by a method having the features of claim 1.

The invention is further based on the object of specifying an arrangement for carrying out the method according to the invention, by means of which triangular packaging bags can be reliably manufactured and filled in the ground plan.

This object is achieved by an arrangement having the features of claim 10.

According to the invention it is proposed to wind a film strip to form a foil coil around a forming mandrel such that its longitudinal edges adjoin one another. The foil coil is pulled off the forming mandrel so far that a first seam section formed by the longitudinal edges and extending in the circumferential direction through 180 ° about the foil coil and a first foil section opposite the first seam section are exposed. The foil coil is compressed in the region of the first seam section, wherein the first seam section is sealed against the first film section to form a first sealed seam. The film coil is further removed from the mandrel so far that a formed by the longitudinal edge, in the circumferential direction by 180 ° around the foil coil extending, adjacent to the first seam section second seam portion and the second seam portion opposite second film portion exposed. The foil coil is compressed in the region of the second seam section, the second seam section being sealed against the second film section to form a second sealed seam crossing the first sealed seam.

The associated arrangement comprises an in particular held stationary feeding device for a film strip, a rotatable about its longitudinal axis and axially displaceable in the direction of the longitudinal axis form dome, a control device for forming a foil coil during winding of the film strip on the forming mandrel and in the region of an output side end of the mandrel arranged sealing device for sealing the foil coil to form the packaging bag.

By generating the foil coil can be dispensed with the required according to the prior art longitudinal seam, while still a closed film tube is formed. A seal has only on the two mentioned seal sections to take place, which contributes to the material savings and reduction of film consumption. The foil coil drawn off from the forming mandrel is forcibly kept open by the forming mandrel in the region of the second sealed seam after the formation of the first sealed seam, so that a secure filling of the packaging bag without rejects is possible. The triangular packaging bags can be manufactured and filled with high efficiency and reliability.

In an advantageous development of the invention, the foil coil is rotated by 180 ° with respect to its longitudinal axis between the sealing of the first seam section and the sealing of the second seam section. The packaging bag to be produced has an average length, wherein in particular the forming mandrel together with the foil spiral are axially displaced in the mentioned 180 ° rotation starting from an initial position about said average length of the packaging bag, wherein the foil coil in this twisted and in particular axially displaced state is held, and wherein then the mandrel and the foil coil are axially displaced against each other such that the foil coil is withdrawn axially from said mandrel about said mean length.

In the associated arrangement, the foil coil has a helical pitch, wherein the control device is designed such that the feed device and the forming mandrel are axially displaced against each other together with the foil helix with a rotation of 180 ° starting from an initial position by half the helix pitch.

This ensures that each individual sealing process is always carried out in the same spatial position. The sealing seams to be sealed in each case are positioned the same in each sealing operation, so that you can work with the same and fixed sealing device.

In a preferred embodiment, the forming mandrel is arranged inclined relative to the horizontal by an inclination angle such that the first or second seam section lies horizontally when being sealed. In the associated arrangement, the foil coil has a pitch angle, wherein the inclination angle of the mandrel is equal to the pitch angle of the foil coil. In particular, the sealing device is arranged horizontally. All in all, this ensures that the seal seam to be sealed off is horizontal. Before sealing, the triangular packaging bag can therefore be filled almost to the brim without the packaged goods falling out of the interior of the still open, not yet sealed packaging bag. In addition, even with a high degree of filling, no packaged goods reach the area of the sealed seam. Despite the high filling level, the triangular packaging bag can be reliably and tightly closed or sealed. For a certain amount of the packaged goods, the packaging bag can be made comparatively small, which further reduces the consumption of film material.

In an expedient development of the invention, the forming mandrel is designed as a forming tube, wherein the filling of the packaging bag takes place through the forming tube before closing the second sealed seam. For this purpose, a filling line for filling the packaging bag is arranged through the forming tube within the forming tube. As a result, a forced filling of the packaging bag spread out by the forming tube is ensured, without the still open, spread-out sealing section being contaminated with the packaged product. The contents can not reach next to the packaging bag, whereby a reliable filling and subsequent, just as reliable sealing of the film bag are ensured.

In a preferred embodiment, the forming mandrel is designed as a radially expandable, in particular from radially displaceable segments formed molding tube. The effective diameter of the forming tube is readjusted during the winding of the foil coil to achieve a desired winding pattern or readjusted. This is particularly advantageous if a certain printing pattern of the film strip must be brought in a certain relative position to the packaging bag. By controlled or regulated adjustment of the effective winding diameter, a reduced or increased length of the film strip is wound with each revolution, whereby a printed pattern applied to the film strip can be brought to the desired position or its position can be corrected.

The longitudinal edges of the foil strip are expediently stapled together to form the foil coil on the mandrel and in particular sealed together overlapping. For this purpose, a sealing device for fixing the film strip in the form of the film spiral is advantageously arranged radially on the outside of the forming mandrel. This ensures that the foil coil retains its shape not only on the mandrel or on the forming tube, but also after removing it until the formation of the sealing seams, which contributes to process safety.

In an advantageous embodiment of the arrangement, a supporting device for the sealed film strip, in particular in the form of a guide tube, is arranged on the side of the sealing device facing away from the output side end of the forming mandrel. The sealed and filled foil strip thus receives a weight force support, so that its own weight does not act on the not yet sealed foil coil. The sealing process can be carried out undisturbed.

On the side of the sealing device facing away from the output end of the forming mandrel, a retaining device for the sealed film strip, in particular in the form of clamping jaws, is advantageously arranged. After the forming mandrel has performed its combined rotational and axial movement together with the foil coil, the already sealed foil strip is captured or fixed by the retaining device. In this state, the mandrel can be pulled back to its original position, without dragging the foil coil. Rather, the foil coil remains in place and location and is thereby subtracted from the mandrel, so that the next, subsequent seal can be completed.

To facilitate the aforementioned process, the mandrel is preferably stirred out as a radially expandable, in particular formed from radially displaceable segments form tube. Here, the foil coil is wound onto the radially expanded forming tube. When the foil coil is pulled off the forming tube, the segments are displaced radially inwards so that the effective diameter of the forming tube is reduced. This facilitates the retraction of the forming tube, without taking the foil coil.

In a preferred embodiment, a spreading device for the foil coil is arranged in the region of the output-side end of the forming mandrel. This facilitates a wrinkle-free sealing of the sealed seams.

With the method according to the invention and with the arrangement according to the invention, a perforation for forming a chain pack comprising a plurality of packaging bags can be arranged, or a separating cut can be carried out to form individualized packaging bags, between the adjacent sealing seams. The invention is therefore very versatile.

Fig. 1

in einer schematischen Draufsicht vereinzelte, im Grundriss dreieckige Verpackungsbeutel, die erfindungsgemäß aus einem zu einer Folienwendel aufgewickelten Folienstreifen hergestellt sind;

Fig. 2

in schematischer Draufsicht eine Kettenpackung mit zusammenhängenden Verpackungsbeuteln nach Fig. 1;

Fig. 3

in einer Seitenansicht eine erfindungsgemäße Anordnung zur Herstellung der Verpackungsbeutel nach den Fig. 1 und 2 mit einem geneigten Formrohr und einer auf das Formrohr schräg aufgewickelten Folienwendel;

Fig. 4

eine schematische Querschnittsdarstellung des Formrohres nach Fig. 3 mit einzelnen, in radialer Richtung verschiebbaren Segmenten;

Fig. 5

eine schematische Detaildarstellung der Anordnung nach Fig. 3 im Bereich des Formrohrendes bei der Bildung einer ersten Siegelnaht;

Fig. 6

die Anordnung nach Fig. 5, bei der die Folienwendel und das Formrohr axial verschoben und um 180° zur Befüllung des Verpackungsbeutels gedreht sind;

Fig. 7

die Anordnung nach Fig. 6 mit zurückgezogenem Formrohr beim Absiegeln der zweiten Siegelnaht;

Fig. 8

die Anordnung nach Fig. 7, bei der das Formrohr und die Folienwendel erneut axial verschoben und um 180° zur Befüllung des nächsten Verpackungsbeutels gedreht sind;

Fig. 9

die Anordnung nach Fig. 8 mit zurückgezogenem Formrohr beim Absiegeln der nächsten Siegelnaht.

Embodiments of the invention are described below with reference to the drawing. Show it:

Fig. 1

in a schematic plan view isolated, in plan view triangular packaging bag, which are made according to the invention from a wound into a foil coil film strip;

Fig. 2

in schematic plan view of a chain pack with contiguous packaging bags after Fig. 1 ;

Fig. 3

in a side view an inventive arrangement for producing the packaging bag according to the Fig. 1 and 2 with a sloping forming tube and a foil coil wound obliquely onto the forming tube;

Fig. 4

a schematic cross-sectional view of the forming tube according to Fig. 3 with individual, radially displaceable segments;

Fig. 5

a schematic detail of the arrangement according to Fig. 3 in the region of the mold tube end in the formation of a first sealed seam;

Fig. 6

the arrangement after Fig. 5 in which the foil coil and the forming tube are axially displaced and rotated by 180 ° to fill the packaging bag;

Fig. 7

the arrangement after Fig. 6 with withdrawn forming tube when sealing the second sealed seam;

Fig. 8

the arrangement after Fig. 7 in which the forming tube and the foil coil are again axially displaced and rotated by 180 ° to fill the next packaging bag;

Fig. 9

the arrangement after Fig. 8 with retracted forming tube when sealing the next sealed seam.

Fig. 1 shows in a schematic plan view of several triangular in plan view packaging bag 1, 1 ', which according to the invention from a in Fig. 3 illustrated film strips 2 are made. The packaging bags 1, 1 'are filled in the exemplary embodiment shown with coffee powder. But you can also contain another, powdery, granular, lumpy or liquid contents.

The packaging bags 1, 1 'are made in one piece. For this purpose, the film material of the film strip 2 ( Fig. 3 ) folded seamlessly at a folded edge 29 and at two adjoining seam edges 27, 28 with a first sealed seam 9, 9 'and a second, the first seal 9, 9' intersecting sealed seam 12, 12 'tightly sealed or sealed together. Due to the folded edge 29 and the sealing seams 9, 9 ', 12, 12' arise in the packaging bags 1, 1 'hermetically closed interior spaces in which the contents is stored.

The outline of the packaging bags 1, 1 'is given by the edges 27, 27', 28, 28 ', 29, 29', which are arranged in the shape of an isosceles triangle. The two seam edges 27, 28 of the packaging bag 1 include a corner angle δ, which in the embodiment shown is 90 °, but may also have a different amount. The folded edge 29 includes with the seam edges 27, 28 each have an acute angle γ, which is in the illustrated embodiment, 45 °, but may also have a different amount. The same applies analogously to the packaging bag 1 'with its seam edges 27', 28 'and their folded edges 29'.

Fig. 2 shows in a schematic plan view of a chain pack 26, by interconnected packaging bag 1, 1 'to Fig. 1 is formed. The packaging bags 1, 1 'are arranged in a row such that the first sealed seam 9 of the packaging bag 1 adjoins the second sealed seam 12' of the adjacent packaging bag 1 ', while the second sealed seam 12' of the packaging bag 1 'adjoins the first sealed seam 9 adjacent the adjacent packaging bag 1. Where the first sealed seam 9 of the packaging bag 1 adjoins the second sealed seam 12 'of the packaging bag 1', a first seam section 7 is formed, whereas where the first Sealing seam 9 'of the packaging bag 1' adjacent to the second sealed seam 12 of the packaging bag 1, a second seam portion 10 is formed. If a chain pack 26 with juxtaposed triangular packaging bags 1, 1 'after Fig. 2 is to be manufactured, the first seam sections 7 between the adjacent sealing seams 9, 12 'and the second seam sections 10 between the adjacent sealing seams 9', 12 each provided with an interrupted perforation 13. As a result, the packaging bags 1, 1 'in the form of the chain pack 26 to each other, but can be separated if necessary by manual tearing.

Alternatively, in the first seam sections 7 between the adjoining sealing seams 9, 12 'and in the second seam sections 10 between the adjoining sealing seams 9', 12 a separation cut along a cutting line 14 can be carried out in each case, as with a solid line also in FIG Fig. 2 is shown. Due to the separating cut along the cutting lines 14, the packaging bags 1, 1 'as shown Fig. 1 sporadically.

Fig. 3 shows a side view of an embodiment of an inventive arrangement for producing and filling the packaging bag 1, 1 'according to the Fig. 1, 2 , The arrangement comprises a packaging machine 30 and a film strip 2. The packaging machine 30 has a frame 34 on which a forming mandrel about its longitudinal axis 15 is rotatably mounted and axially displaceable in the direction of the longitudinal axis 15. The mandrel may be made solid and is executed in the illustrated embodiment as described below in more detail form tube 6. The longitudinal axis 15 of the forming tube 6 is inclined relative to the horizontal by an inclination angle α, which is 45 ° in the embodiment shown. The forming tube 6 is a film strip 2 held horizontally in the direction of an arrow 31 by means of a fixedly held on the frame 34 feeding device 37 while rotating and simultaneous axial displacement of the forming tube 6 according to arrows 33, 32 on the outer peripheral surface wound helically, whereby there forms a foil coil 5. Alternatively, a film strip 2 'corresponding to an arrow 31' vertically or from another direction can be supplied to the forming tube 6. Furthermore, an arrangement may be expedient in which the forming tube 6 is held stationary on the frame 34, and in which the feeder 37 is guided around the forming tube 6 to form the foil coil 5. In any case, a control device 16 ensures that the feeder 37 on the one hand and the Formdrohr 6 together with the film coil 5 on the other hand with a rotation of 180 °, starting from an initial position by half a helical pitch a axially against each other or relative to each other.

The film strip 2 is bounded by two laterally opposite, the width of the film strip 2 predetermining longitudinal edges 3, 4. The width of the foil strip 2, the diameter of the forming tube 6 and the feeding angle of the foil strip 2 to the forming tube 6 are coordinated such that the film strip 2 is wound around the forming tube 6 to form the foil coil 5 such that the longitudinal edge 4 of a film winding to the Longitudinal edge 3 of the adjacent Folienwindung adjacent. In the illustrated embodiment, the longitudinal edge 4 overlaps within the foil coil 5, the adjacent and dashed longitudinal edge 3 by a certain predetermined amount. There is radially outside of the forming tube 6, a sealing device 25 for mutual fixation of the overlapping longitudinal edges 3, 4 are arranged. By means of the schematically indicated sealing device 25, the overlapping longitudinal edges 3, 4 of the film strip 2 are stitched together to form the film coil 5 on the forming tube 6 by a sealing process. Instead of a sealing process with hot or cold seal glue, another suitable form of stitching may also be expedient, even if the overlapping of the longitudinal edges 3, 4 is dispensed with.

The wound on the forming tube 6 foil coil 5 is located with the longitudinal edges 3, 4 relative to the longitudinal axis 15 of the forming tube 6 in a pitch angle β . From this and from the circumference of the forming tube 6 also results in a measured in the direction of the longitudinal axis 15 helical pitch a as a distance between two adjacent film turns. The pitch angle β is identical to the in Fig. 1 shown tip angle γ of the packaging bag 1, 1 'before, is therefore chosen here at 45 °. Of course, by geometric adjustment and a different angle β can be adjusted. In addition, the packaging bags 1, 1 'after Fig. 1 a measured parallel to the folded edge 29 average length 1. The spiral pitch a ( Fig. 3 ) is twice the said average length 1.

The packaging machine 30 is provided with a control device 16 for forming the film coil 5 when winding the film strip 2 onto the forming tube 6. The control device 16 brings about that the forming tube 6 is evenly displaced axially in the direction of an arrow 32 in a rotation corresponding to the arrow 33. The rotational movement in the direction of the arrow 33 and the axial displacement movement in the direction of the arrow 32 are coupled to one another such that the film strip can be kept unchanged without tracking in its spatial position, is only deducted in the direction of arrow 31 of the feeder 37 and it winds to the uniform foil coil 5 on the forming tube 6. The control device 16 can be electronically controlled and, for example, driven by stepper motors in both degrees of freedom of movement. In the illustrated embodiment, the control device 16 is formed by a helical spiral surface 19 and a voltage applied to the spiral surface 19 guide pin 20. The helical surface 19 is fixedly connected to the frame 34, while the guide pin 20 is fixedly connected to the forming tube 6. But it can also be an inverse embodiment appropriate. The helical surface 19 passes through 180 ° about the longitudinal axis 15 and extends in the axial direction over half the helical pitch a. The voltage applied to the helical surface 19 guide pin 20 leads to a rotation of the forming tube. 6 180 ° to the fact that said rotational movement is converted according to the arrow 33 in an axial stroke corresponding to the arrow 32, wherein said axial stroke is half of the helical pitch a.

The representation after Fig. 3 is in synopsis with Fig. 4 it can be seen that the forming tube 6 in the same area in which the foil coil 5 is formed by winding the foil strip 2, is cylindrical. But it can also be useful another cross-sectional shape. In the region of its lower, output-side end 17, the forming tube 6 can optionally be tapered with respect to its cross-section. In the region of this tapered end 17 is a sealing device 18 for sealing the film coil 5 to form the packaging bag 1, 1 '( Fig. 1, 2) arranged. To support this sealing process, a spreader 38 for the film coil 5 is still arranged in the region of the output-side end 17, which is formed in the illustrated embodiment by a pair of spreading fingers. By means of the spreading device 38, the initially cylindrical foil coil 5 is spread on the input side of the sealing device 18 to a flat, double-layered web and fed to the sealing device 18 in this spread-apart state. In addition, within the forming tube 6, an indicated filling line 23 for filling the packaging bags 1, 1 'passes through the forming tube 6. The function of the latter components will be described in more detail below.

Fig. 5 shows in a schematic and enlarged detail view of the arrangement according to Fig. 3 in the region of the lower end 17 of the forming tube 6 with the lower end of the filling line 23. The foil coil 5 is deducted so far from the mandrel 6 beyond its end 17, that by the longitudinal edges 3, 4 ( Fig. 3 ) formed and in the circumferential direction by 180 ° around the film coil 5 extending first seam section 7 is exposed, so is no longer supported by the forming tube 6. The first seam section 7 lies here on the side facing away from the viewer of the film coil 5 and is therefore shown in dashed lines. The first seam section 7 is a continuous, undisturbed first film section 8 opposite. The first film section 8 lies on the viewer facing side of the film coil 5 and, like the first seam section 7 is not supported by the forming tube 6, so is free.

From the synopsis of Fig. 3 and 5 It can be seen that the angle of inclination α of the forming tube 6 is chosen to be equal to the angle of inclination β of the foil coil 5, that is to say the first seam section 7 (FIG. Fig. 5 ) is horizontal in this state. Also in Fig. 3 Sealing device 18 shown extends horizontally and thereby spans the first seam section 7 (FIG. Fig. 5 ). The sealing device 18 ( Fig. 3 ) comprises two sealing jaws, not shown, between which by means of the spreader 38 ( Fig. 3 ) spread and flat folded foil coil 5 is passed. By compressing the sealing jaws and the foil coil 5 according to the illustration after Fig. 5 compressed in the region of the first seam section 7, wherein the first seam section 7 is sealed against the first film section 8. In this case, a first sealed seam 9 of the packaging bag 1 and a second sealed seam 12 'are formed. The packaging bag 1 is thereby tightly sealed at its first sealed seam 9. For the sealing process, the film strip 2 ( Fig. 3 ) provided on its inside with a sealing layer, which may be configured as a cold or heat-sealing film. Other sealing aids may be appropriate.

In addition, adjoining the horizontally extending first seam section 7 is still a second seam section 10, which follows in the position Fig. 5 extends vertically over the end 17 of the forming tube 6, that is still supported by the forming tube 6.

Starting from the initial situation Fig. 5 the arrangement shown there is rotated about the longitudinal axis 15 by an angle of 180 °, as in Fig. 6 is shown. The control device 16 (FIG. Fig. 3 ) causes concomitantly that the forming tube 6 together with the foil coil 5 and the filling line 23 in the direction of the longitudinal axis 15, starting from the starting position to Fig. 5 performs an axial stroke h, the same the half spiral pitch a ( Fig. 3 ) and thus equal to the mean length 1 ( Fig. 1 ). In the rotated position to Fig. 6 the first seam section 7 is vertical, while the adjoining second seam section 10 of the packaging bag 1 extends horizontally. Since the second seam section 10 also extends beyond the end 17 of the forming tube 6, the packaging bag 1 is widened in the region of the second seam section 10, so that a filling opening of the packaging bag 1 is formed. In addition, the end of the filling line 23 protrudes into the interior of the still unopened packaging bag 1 inside. The packaging bag 1 is in the state after Fig. 6 filled through the filling line 23 therethrough. As a result of the horizontal position of the second seam section 10, this filling can take place almost completely without the filling material emerging from the open second seam section 10 or contaminating the second seam section 10.

In Fig. 3 a retaining device for the sealed film strip 2 is indicated, which is designed in the illustrated embodiment in the form of a pair of clamping jaws 22. In the filled state after Fig. 6 is the film strip 2 ( Fig. 3 ) or the chain pack 26 formed therefrom by means of the clamping jaws 22. In this case, then the forming tube 6, together with the filling line 23, starting from the position to Fig. 6 retracted axially by the stroke h, as in Fig. 7 is shown. If an embodiment with a fixed mold tube 6 is provided, the foil coil 5 is in turn drawn off from the mold tube 6 by means of a retainer movable by the stroke h. In any case, there is an axial relative displacement between the film coil 5 and the forming tube 6 such that as a result the film coil 5 is subtracted from the forming tube 6 by the stroke h or the mean length 1.

In order for this to be possible smoothly and without slippage of the foil coil 5, the forming mandrel is embodied as a radially expandable shaping tube 6 formed here from radially displaceable segments 24. A schematic cross-sectional view of this embodiment of the forming tube 6 is shown in FIG Fig. 4 shown.

Accordingly, the forming tube 6 is composed in its cross section from here by way of example eight segments 24, which are mounted radially movable according to double arrows 35. On the outside, the segments 24 are surrounded by an elastic, cylindrical shell 36, which may be formed, for example, from elastic silicone plastic or the like. In the cross-sectional state which has been widened radially to nominal size, the foil coil 5 (FIG. Fig. 3 ) wound on the outer surface of the elastic jacket 36. During axial retraction of the forming tube 6 as shown Fig. 7 the segments 24 ( Fig. 4 ) is displaced radially inwardly, whereby the outer diameter of the elastic jacket 36 is reduced. Optionally, however, it is also possible to dispense with the elastic jacket 36, in which case the foil coil 5 (FIG. Fig. 3 ) rests directly on the outer surfaces of the segments 24. In any case, the radially inwardly directed movement of the segments 24 causes the cross-section of the forming tube 6 to be reduced, as a result of which there is no appreciable stiction between the foil coil 5 and the outer surface of the forming tube 6 when the foil coil 5 is withdrawn. The forming tube 6 can axially with a small amount of effort to the stroke h according to the illustration Fig. 7 be withdrawn without the fixed by the jaws 22 foil coil 5 ( Fig. 3 ) with withdraw.

Accordingly, the condition is following Fig. 7 a, in which the film coil 5 is deducted from the forming tube 6 so far to the stroke h, that now also formed by the longitudinal edges 3, 4, in the circumferential direction by 180 ° to the foil coil 5 extending, adjacent to the first seam section 7 second Seam section 10 is exposed. The second seam portion 10 faces a continuous, also exposed film portion 11, wherein for the second seam portion 10 and the second film portion 11, the same as that for the first seam portion 7 and the first film portion 8 in connection with Fig. 5 The above applies. The second seam section 10 intersects the first seam section 7. The second seam section 10 follows as shown Fig. 7 also horizontally and by the sealing device 18 ( Fig. 3 ). The Foil coil 5 is now compressed in the region of the second seam section 10, wherein the second seam section 10 is sealed against the second film section 11 to form the second seal seam 12 crossing the first sealed seam 9. This is the after Fig. 5 prepared by means of the first seal 9 and after Fig. 6 filled packaging bags 1 closed and completely sealed. In addition, the first sealing seam 9 'of the following packaging bag 1' is simultaneously formed by the last-mentioned sealing process in the second seam section 10.

Comparable to the representation after Fig. 6 will move from the position to Fig. 7 the arrangement rotated once more by 180 ° about the longitudinal axis 5 and thereby axially displaced by the stroke h, so that now according to the illustration Fig. 8 the second seam section 10 comes to lie perpendicular. A first, horizontally extending seam section 7 again adjoins this second seam section 10 lying perpendicularly, within which, comparable to the representation according to FIG Fig. 6 the end 17 of the forming tube 6 is located. In this position, the packaging bag 1 'following the already filled packaging bag 1 and prepared by the first sealed seam 9' becomes comparable to the arrangement Fig. 6 filled.

In addition, the film strip 2 or the chain pack 26 ( Fig. 3 ) again held by the jaws 22, in order subsequent to the filling of the packaging bag 1, an axial retraction of the guide tube 6 by the stroke h as shown Fig. 9 to enable. In the state after Fig. 9 becomes then comparable to the representations after the FIGS. 5 and 7 the now lying horizontal first seam portion 7 sealed, with a first seal seam 9 'crossing second seam 12' of the packaging bag 1 'is formed, and then what the packaging bag 1' is closed. At the same time, the first sealed seam 9 of the adjoining, not yet filled packaging bag 1 is formed, whereby a complete sealing cycle is completed. The condition after Fig. 9 thus corresponds to the initial state Fig. 5 ,

The cycle after the Fig. 5 to 9 can be repeated as often as desired, until an arbitrarily long chain pack 26 ( Fig. 2 ) or any number of individual packaging bags 1, 1 '( Fig. 1 ) is made.

The representation after Fig. 3 It can also be seen that on the side facing away from the output side end 17 of the forming tube 6 of the sealing device 18 between this and the clamping packing 22 a support means for the sealed film strip 2 and for the filled chain pack 26 formed therefrom is arranged. In the exemplary embodiment shown, this support device is stirred in the form of a guide tube 21, through which the sealed film strip 2 passes. The guide tube 21 is rotated synchronously with the forming tube 6 and supports the weight of the foil strip 3 processed and filled into triangular packaging bags 1, 1 ', so that the foil coil 5 is relieved, in particular in the area of the sealing device 18.

With simultaneous reference to the Fig. 2 and 3 is still to be carried out that the separating cut at the cutting line 14 and the perforation 13 on the output side of the jaws 22 or directly to the jaws 22 can be performed. In the latter case, the jaws 22 are provided with a cutting knife, not shown. In the event that a chain pack 26 is produced and therefore only one perforation 13 is to be attached, the perforation 13 can also be made by appropriate knives on the sealing device 18.

Of the Fig. 3 can be seen that the film strip 2 is provided at regular intervals with here indicated print marks 39. When printing the film strip 2 with a printing pattern, not shown, it may be desirable that this printing pattern in a certain recurring position on the packaging bags 1, 1 '( Fig. 1, 2) to come to rest, which is ensured with the print marks 39 and, for example, a non-illustrated opto-electronic pressure mark detection shall be. In Fig. 3 It can be seen that the print marks 39 always lie in the same circumferential position on the forming tube 6 in the area of the foil coil 5. This leads to the fact that also the aforementioned printing pattern always in the desired position on the packaging bags 1, 1 '( Fig. 1, 2) to come to rest. But there may be deviations of the position of the print marks 39 from their desired position on the forming tube 6, which are detected by the aforementioned print mark detection.

The taken from the feeder 37 and wound length of the film strip 2 depends functionally directly from the effective or effective scope of the forming tube 6 from. Via a control device or via a control circuit, the effective diameter or circumference of the adjustable cross-section mold tube 6 after Fig. 4 be tracked on the basis of the print mark detection that with each revolution of the forming tube 6, an enlarged or reduced length of the film strip 2 is wound up. This length adjustment can be made such that the aforementioned deviations are compensated and the print marks 39 are at their intended target position. This is an exact positioning of the print pattern on the packaging bags 1, 1 '( Fig. 1, 2) ensured.

Claims (21)

1. A method for producing packaging bags (1, 1') having a triangular outline, made of a film strip (2) having two longitudinal edges (3, 4) located opposite each other, comprises the following steps:

   - The film strip (2) is wound about a shaping mandrel forming a film spiral (5) in such a way that its longitudinal edges (3, 4) adjoin each other;

   - The film spiral (5) is pulled off the shaping mandrel so far that a first seam section (7), formed by the longitudinal edges (3, 4) and extending in the circumferential direction about 180° around the film spiral (5), and a first film section (8) opposite of the first seam section (7) are exposed;

   - The film spiral (5) is compressed in the region of the first seam section (7),
   wherein the first seam section (7) is sealed off against the first film section (8) to form a first sealed seam (9, 9');

   - The film spiral (5) is pulled off the shaping mandrel so far that a second seam section (10), formed by the longitudinal edges (3, 4) and extending in the circumferential direction about 180° around the film spiral (5), and abutting the first seam section (7) and a second film section (11) opposite of the second seam section (10) are exposed;

   - The film spiral (5) is compressed in the area of the second seam section (10), so that the second seam section (10) is sealed off against the second film section (11) to form a second seal (12, 12') crossing the first sealed seam (9, 9');
2. The method according to claim 1,
   characterised in that the film spiral (5) is rotated relative to its longitudinal axis about 180° between the first seam section (7) and the second seam section (10).
3. The method according to claim 2,
   characterised in that the packaging bag (1, 1') has an average length (1), in that the shaping mandrel is rotated together with the film spiral (5) about 180° and, in particular, can be displaced axially from an initial position to the average length (1); in that the film spiral (5) is held in the rotated position and, in particular, in an axially displaced condition; and in that subsequently the shaping mandrel and the film spiral (5) are so mutually displaced axially, that the foil spiral (5) is axially removed from the shaping mandrel around the average length (1).
4. The method according to claim 2 or 3,
   characterised in that the shaping mandrel is arranged inclined with respect to the horizontal by an angle of inclination (α) so that the first and the second seam section (7, 10) remain horizontal while sealing.
5. The method according to one of claims 1 to 4,
   characterised in that the shaping mandrel is designed as a shaped tube (6) and that the filling of the packaging bag (1, 1') takes place through the shaped tube (6) before closing the second seal (12, 12').
6. The method according to one of claims 1 to 5,
   characterised in that the shaping mandrel is designed as a shaped tube (6) formed by radially expandable and, in particular, radially movable segments (24), and in that the effective diameter of the shaped tube (6) is adjusted and readjusted in order to obtain a desired winding pattern during winding of the film spiral (5).
7. The method according to one of claims 1 to 6,
   characterised in that the longitudinal edges (3, 4) of the film strip (2) are stapled together and, in particular, sealed together by overlapping in order to form the film spiral (5) in the shaping mandrel.
8. The method according to one of claims 1 to 7,
   characterised in that the first and second seam section (7, 10) is provided with a perforation (13) between the adjacent sealed seams (9, 12'; 9', 12) in order to form a comprehensive chain packing of packaging bags (1, 1').
9. The method according to one of claims 1 to 8,
   characterised in that in the first and second seam section (7, 10), between the adjacent sealed seams (9, 12'; 9', 12), a separating cut along a cutting line (14) is performed to form individual packaging bags (1, 1').
10. Arrangement for producing triangular packaging bags (1, 1'), having a triangular outline, according to the method of one of claims 1 to 9, comprising a shaping mandrel, a feed device (37) for a film strip (2) with longitudinal edges (3, 4), a control device (16) to form a film spiral (5) during the winding of the film strip (2) onto the shaping mandrel in such a way that the longitudinal edges (3, 4) of the film strip (2) adjoin each other, as well as a sealing device (18) arranged on the output-side end (17) of the shaping mandrel, to seal off the film spiral (5) forming the packaging bag (1, 1'), wherein the sealing device (18) is designed such that a first seam section (7) formed by the longitudinal edges (3, 4) and extending through 180° in the circumferential direction around the film spiral (5) is sealed off from a first film section (8) opposite the first seam section (7), and a second seam section (10) formed by the longitudinal edges (3, 4), extending through 180° in the circumferential direction around the film spiral (5) and adjoining the first seam section (7) is sealed off from a second film section (11) opposite the second seam section (10).
11. The arrangement according to claim 10,
    characterised in that the feed device (37) for the film strip (2) is held stationary, and in that the shaping mandrel to form the film spiral (5) is mounted so that it can rotate about its longitudinal axis (15) and in the direction of its longitudinal axis (15), and be displaced axially.
12. The arrangement according to claim 10 or 11,
    characterised in that the film spiral (5) is provided with an helical pitch (a) and that the control device (16) is such designed that the feed device (37) and the shaping mandrel together with the film spiral (5) are displaced axially against one another with a 180° rotation starting from an initial position at about half of the helical pitch (a).
13. The arrangement according to claim 12, •
    characterised in that the control device (16) is formed by a helical surface (19) and a guiding mandrel (20) placed on the helical surface (19).
14. The arrangement according to one of claims 10 to 13,
    characterised in that the film spiral (5) is provided with a pitch angle (β) and that the shaping mandrel is arranged inclined with respect to the horizontal by an angle of inclination (α), wherein the angle of inclination (α) is equal to the pitch angle (β).
15. The arrangement according to claim 14,
    characterised in that the sealing device (18) is arranged horizontally.
16. The arrangement according to one of claims 10 to 15,
    characterised in that on the output-side end (17) of the sealing device (18) is arranged a support device for the film strip (2), in particular in the form of a guiding tube (21).
17. The arrangement according to one of claims 10 to 16,
    characterised in that on the output-side end (17) of the sealing device (18) is arranged a retaining device for the sealed film strip (2), in particular in the form of clamping jaws (22).
18. The arrangement according to one of claims 10 to 17,
    characterised in that the shaping mandrel is designed as a shaped tube (6) and that inside the shaped tube (6) is inserted a filling pipe (23) to fill the packaging bag (1, 1') through the shaped tube (6).
19. The arrangement according to one of claims 10 to 18,
    characterised in that the shaping mandrel is formed by radially expandable and, in particular, radially movable segments (24).
20. The arrangement according to one of claims 10 to 19,
    characterised in that the radially outwardly part of the shaping mandrel is arranged a sealing device (25) to fix the film strip (2) in the form of the film spiral (5).
21. The arrangement according to one of claims 10 to 20,
    characterised in that in the region of the output-side end (17) a spraying device (38) for the film spiral (5) is arranged.

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