EP0052151B1 - Ply-bottom bag and apparatus for making it - Google Patents

Abstract

1. Bag with a fold in the bottom with two lateral faces (1, 1'), with a v-shaped bottom (2) folded inwards, with longitudinal seams (3) which extend at least until the v-shaped fold and with at least four lateral v bottom seams (4) which are inclined, and which combine only one lateral face (1, 1') each with a side of the v of the bottom (2), showing a starting point (5) on the corresponding longitudinal seam (3) on the level of the fold in the bottom, characterized in that the bag is formed of at least two pieces of foil (28, 29), showing a cover (6) which is formed according to the bottom (2), in case of which four lateral cover seams (7) are inclined according to the bottom seams and that one lateral face (1') as well as the adjacent side of the v of the cover (6) are prolonged beyond the transversal brim of the cover and form commonly a filling respectively discharge socket (socket 8) with longitudinal seams (9).

Description

The invention relates to a bottom gusseted bag with two side surfaces, with a V-shaped bottom folded inwards, with longitudinal seams which extend at least to the V-fold and with at least four lateral, inclined bottom seams, each with only one side surface with a V- Connect the legs of the bottom and have a starting point lying on the corresponding longitudinal seam at the level of the bottom fold.

"Seams" are understood to mean welds or seals.

The above embodiment can be found in DE-B-1 2 81 140. The four side bottom seams are arranged at an angle, while the longitudinal seams also extend across the height of the bottom and here connect all four layers of foil. The top of the bag is open or closed with a cross seam. The bottom gusseted bag can be made from a single film web or from three film webs.

From AT-A-271 322 it is known to form a bottom gusseted bag with a lid, a three-layer weld being provided in the lid area, which connects a wall and two side gussets to one another. This welding is interrupted to form a gap which is used to insert a drinking straw. The three-layer welding results in a wedge-shaped construction of the bottom gusseted bag, which is made from a gusseted tube.

DE-A-26 13 724 discloses a gusseted bag which has a square bottom and which can be produced from two sheets of film. The flattened bag is rectangular in plan view, the inner folds of the two inserted between the side walls front wall and rear wall butt against each other. The side walls, each consisting of a single rectangular section, are connected with their vertical side edges to the corresponding edges of the front wall and rear wall, and with their lower transverse edge to an opposite transverse edge of the square base. The latter has a weld or sealing seam running all around, consists of a single film web section together with the front wall and the rear wall and, when the bag is laid flat, is folded triangularly into the interior of the bag via its diagonals. To produce this bag, an interruption in the production process and a separate manipulation of the individual sections are required, so that the overall production proves to be complex.

The film width for flat sheets is usually a maximum of 1.30 m. If the bottom gusset bag explained at the beginning were produced from only one flat web, the bag height would thus be limited.

The invention has for its object to improve the bottom gusset bag explained in terms of its uses and its manufacture.

This object is achieved according to the invention in that it is formed from at least two film parts and has a cover designed according to the bottom, in which four side cover seams run obliquely according to the bottom seams, and that a side surface and the adjacent V-leg of the cover are extended beyond the top edge of the lid and together form a filler or emptying nozzle (spout) with longitudinal seams.

The bottom gusseted bag according to the invention can be produced from e.g. thermoplastic foils that are heat sealable. One then speaks of sealed seams. The thermoplastic plastic films can also be weldable. One then speaks of separating seam welds. The term "seam" most often used in this application is intended to include the two alternatives mentioned above, while the term "gluing" is also intended to include "sealing" or "welding".

The thermoplastic plastic films can be formed in one layer and e.g. are made of polyethylene or polypropylene. But they can also be multi-layered; it is then a question of composite films. Other possible starting materials are paper-plastic composites that are heat-sealable, plastic-plastic films that are cold-sealable, and plastic-coated paper webs that are cold-sealable or heat-sealable. The term "film" most commonly used in the application is intended to encompass all possible alternatives.

According to the invention, it is preferred if the longitudinal seams also extend over the height of the floor. as well as the cover and in this area connect only its side surface with a V-leg of the bottom or the cover. In a further development of this embodiment, two or more longitudinal seams arranged next to one another at a distance can be advantageous, the longitudinal strips thus formed being folded inwards onto one or the other side surface and glued to it. In principle, it is possible to reverse the folding or in the same direction. To increase the stability of the bag, it can also be advantageous if a reinforced adhesive strip is inserted between the folded longitudinal strips and the associated side surface.

In a bag according to the invention with only simple longitudinal seams and oblique side bottom and lid seams, it is advantageous if the four formed by the oblique side bottom seams with the longitudinal edge Triangular sections as well as the corresponding triangular sections of the lid are separated.

In order to be able to also produce larger bags from narrower film webs, it is expedient if the V-shaped bottom and one side surface with a spout are made from one film part and the other side surface and the V-shaped lid with a spout are folded from a second film part. It is then worked from two roller conveyors, the bags being produced transversely to the running direction of the two roller conveyors.

In order to be able to also produce larger bags from narrower film webs, it is expedient if the V-shaped bottom and one side surface with a spout are made from one film part and the other side surface and the V-shaped lid with a spout are folded from a second film part. It is then worked from two roller conveyors, the bags being produced transversely to the running direction of the two roller conveyors.

In particular in the case of comparatively large bottom gusseted bags, it can be advantageous if the one side surface is made of a first film part, the V-shaped bottom is made of a second film part, the V-shaped cover is made of a third film part and the other side surface is made of a fourth film part consist.

In a further development of the previously described bottom gusseted bag, it is possible to provide an intermediate bottom which divides the bag into two chambers and consists of a fifth film part, and a second spout on the bottom. This intermediate bottom can in turn be folded in a V-shape, the edges of the V-legs being connected to the side surfaces of the bag via corresponding seams. To increase the stability, the intermediate floor can also consist of a closed hose or e.g. be designed as a filter.

If the new bottom gusseted bag is inflated or filled, its bag body will automatically inflate. Not only the filled, but also the only inflated empty bag are absolutely stable. The new bag can be shaped, sealed or welded, filled and closed fully automatically on a form, fill and seal machine; it can also be packaged as an empty bag and then Round fillers can be filled and sealed as a solo pack or in a cardboard box. As an inner bag in the outer carton, the bottom gusseted bag according to the invention offers i.a. the main advantage that it inflates automatically during filling, so that the outer carton, which is expediently only slightly formed for cost reasons, does not have to be mechanically erected into the filling state by an erecting machine. In addition, gluing between the inner bag and outer carton is no longer necessary, which saves further costs.

Finally, the new bag can be filled up to the lower edge of the filling or emptying nozzle and thus completely, so that no empty space or air space remains. That is why the bag body maintains its stable shape even when evacuating.

The spout provided on the new bag enables the finished packaging to be reclosed and thus also gradually emptied. In addition, the bag can be easily sealed airtight after it has been filled by welding or sealing the spout opening.

• a) Zwei mit Abstand nebeneinander angeordnete Klemmbackenpaare, zwischen denen die vorgefaltete Folie einspannbar ist, wobei das eine Paarteil eine Art Ziehmatrize und das andere Paarteil eine Art Niederhalter darstellen;
• b) im Niederhalter sind ein jeweils senkrecht zur Folienebene verschiebbares Trennmesser sowie ein Druckstempel angeordnet;
• c) die Ziehmatrize weist innere verschiebbare Andrückleisten auf;
• d) in der Ziehmatrize sind zum Druckstempel gegenläufig arbeitende, zur Herstellung der Längsnähte dienende Schweiß- oder Siegelbacken mit ausschwenkbaren Andrückklappen angeordnet, die in ausgeschwenkter Stellung in den Verschiebebereich der Andrückleisten ragen.

A device for producing the bags, each of which has two or more longitudinal seams arranged at a distance from one another, the longitudinal strips thus formed being folded inwards and glued to one or the other side surface, are preferably characterized by the following features:

• a) Two pairs of clamping jaws arranged at a distance from one another, between which the pre-folded film can be clamped, one pair of parts being a kind of drawing die and the other pairing being a kind of hold-down device;
• b) a separating knife, which can be moved perpendicular to the film plane, and a pressure stamp are arranged in the hold-down device;
• c) the drawing die has inner displaceable pressure strips;
• d) in the drawing die, there are welding or sealing jaws which work in opposite directions to the pressure stamp and which serve to produce the longitudinal seams, with swiveling pressure flaps which, in the swiveled-out position, project into the displacement area of the pressure bars.

It is expedient here if inwardly directed glue spray nozzles are arranged in the free edge region of the fixed part of the drawing die. In addition, the separating knife can be arranged in the pressure stamp and the welding or sealing jaws form the counter bearing for the separating knife.

However, it is also possible to arrange separate vertical sealing tools for the sealing of the longitudinal seams, namely — in the pull-off direction of the film web — in front of the clamping jaw pairs explained above. In this case, the tool referred to above as welding or sealing jaws is used exclusively for folding and pressing the longitudinal strips of the bag.

• Figur 1 in perspektivischer Darstellung einen Bodenfaltenbeutel mit Siegelnähten;
• Figur 2 in verkleinertem Maßstab einen lotrechten Querschnitt durch den Beutel gemäß Figur 1;
• Figur 3 in Explosionsdarstellung die Siegel-und Trennwerkzeuge zur Herstellung eines Beutels gemäß Figur 1 ;
• Figur 4 in Draufsicht einen flachgelegten Beutel gemäß Fig. 1 mit abgetrennten Abfällen;
• Figur 5 in einer Darstellung gemäß Figur 1 eine abgewandelte Ausführungsform eines Bodenfaltenbeutels;
• Figur 6 in einer Darstellung gemäß Figur 3 die Siegel- und Trennwerkzeuge zur Herstellung eines Beutels gemäß Figur 5;
• Figur 7 in schematischer Darstellung die Verarbeitung von zwei Rollenbahnen zur Herstellung von Beuteln gemäß Figur 1;
• Figur 8 in einer Darstellung gemäß Figur 7 die Verarbeitung von vier Rollenbahnen zur Herstellung von Beuteln gemäß Figur 1;
• Figur 9 in einer Darstellung gemäß Figur 1 einen Bodenfaltenbeutel mit nach vorn gefalteten Längsstreifen;
• Figur 10 in einer Darstellung gemäß Figur 9 einen Bodenfaltenbeutel mit zwei Kammern und zwei Tüllen;
• Figur 11 in einer Darstellung gemäß Figur 10 einen Bodenfaltenbeutel mit zwei Kammern und vier Tüllen;
• Figur 1-2 in einer Darstellung gemäß den Figuren 7 und 8 die Verarbeitung von fünf Rollenbahnen zur Herstellung von Beuteln gemäß Figur 10;
• Figur 13 in einer Darstellung gemäß Figur 12 die Verarbeitung von fünf Rollenbahnen zur Herstellung von Beuteln gemäß Figur 1 1;
• Figur 14 in einer Darstellung gemäß den Figuren 3 und 6 Schweiß- und Trennwerkzeuge zur Herstellung von Beuteln gemäß Figur 9;
• Figur 15 Werkzeuge zum Herstellen in Umfalten der Längsstreifen eines Beutels gemäß Figur 9;
• Figur 16 in einer Darstellung gemäß Figur 14 die Schweiß und Trennwerkzeuge zur Herstellung eines Beutels gemäß Figur 10 und
• Figur 17 die Anordnung gemäß Figur 16 zur Herstellung von Beuteln gemäß Figur 11.

Some exemplary embodiments of the invention are shown in the drawing. Show it:

• Figure 1 is a perspective view of a bottom gusseted bag with sealed seams;
• FIG. 2 shows, on a reduced scale, a vertical cross section through the bag according to FIG. 1;
• 3 shows an exploded view of the sealing and separating tools for producing a bag according to FIG. 1;
• Figure 4 is a top view of a flat bag according to Figure 1 with separated waste.
• Figure 5 in a representation according to Figure 1 shows a modified embodiment of a bottom gusseted bag;
• FIG. 6 shows the sealing and separating tools for producing a bag according to FIG. 5 in a representation according to FIG. 3;
• FIG. 7 shows a schematic representation of the processing of two roller conveyors for the production of bags according to FIG. 1;
• Figure 8 in a representation according to Figure 7, the processing of four roller conveyors for the production of bags according to Figure 1;
• FIG. 9 shows a bottom gusset bag with longitudinal strips folded forward in a representation according to FIG. 1;
• FIG. 10 shows a bottom gusseted bag with two chambers and two spouts in a representation according to FIG. 9;
• FIG. 11 shows a bottom gusseted bag with two chambers and four spouts in a representation according to FIG. 10;
• Figure 1-2 in a representation according to Figures 7 and 8, the processing of five roller conveyors for the production of bags according to Figure 10;
• FIG. 13 shows the processing of five roller conveyors for the production of bags according to FIG. 11 in a representation according to FIG. 12;
• FIG. 14 in a representation according to FIGS. 3 and 6, welding and separating tools for producing bags according to FIG. 9;
• FIG. 15 tools for producing by folding the longitudinal strips of a bag according to FIG. 9;
• FIG. 16 shows the welding and separating tools for producing a bag according to FIG. 10 and in a representation according to FIG. 14
• FIG. 17 shows the arrangement according to FIG. 16 for the production of bags according to FIG. 11.

The bottom gusset bag shown in FIGS. 1, 2 and 4 has two side surfaces 1 which, with a bottom 2 which is connected to them in a V-shape and which are folded inwards, form a W with four foil layers in the bottom region (see in particular FIG. 2). The bottom gusset bag also has two longitudinal seams 3, which extend over the entire height of the side surfaces 1. In the bottom area, four sloping bottom seams 4 are provided, which only extend in the zone of the W, which is formed by the side surfaces 1 and the bottom 2. Each bottom seam 4 connects only one side surface 1 to a V-leg of the bottom 2 and has a starting point 5 lying on the corresponding longitudinal seam 3 at the level of the bottom fold 2a. Furthermore, a cover 6 designed in accordance with the bottom 2 is provided, the four side cover seams 7 of which also run obliquely. The one side surface 1 'and the adjacent V-leg of the cover 6 are extended beyond the transverse edge of the cover and together form a filler or emptying nozzle 8 (spout) with longitudinal seams 9. The latter are connected to the two oblique side surfaces 1' with lid seams 7 connecting lid 6.

The processing of a hose 11 can be seen in FIG. 3. The bottom transverse sealing seams 13 are sealed at the front and rear with a transverse sealing tool 12. At the same time, in the lid area, but only in the front part of the lid fold, the lid-transverse sealing seam 15 is sealed with the cross-sealing tool 14. In order to prevent sealing in the rear area through the spout 8, an intermediate plate 16 has been inserted into the cover fold. Oblique tools 17 seal the oblique lid seams 7 and, with a vertical leg, also the longitudinal seams 9 of the spout 8. Triangular tools 18 seal the oblique bottom seams 4. The upper waste sections 19 shown in FIG. 4 are punched out with oblique cutting knives 20, while the lower ones shown in FIG. 4 Waste sections 21 are punched out with triangular cutting blades 22. Vertical sealing tools 23 seal the longitudinal seams 3, while the longitudinal separation is carried out between two bags by means of vertical separating knives 24.

Figure 3 shows that the tools 17, 18, 20, 22 and 23 are mirror-symmetrical to the longitudinal edge of the bag.

The triangular lower waste sections 21 shown in FIG. 4 do not necessarily have to be separated, but could also remain on the bag. The longitudinal seams 3 would then also extend over the height of the base and in this area would connect only one side surface 1, 1 'to a V-leg of the base 2.

The bottom fold bag shown in FIG. 5 differs from that according to FIG. 1 only in that the triangular lower waste sections 21 shown in FIG. 4 and the parts corresponding to them have not been punched out in the lid area. The longitudinal seams 3 also extend over the height of the base 2 and the cover 3 and connect all four layers of film in this area. The shape of this bag in a flat position is shown in FIG. 6. Here, the transverse sealing tools 12 for producing the bottom transverse sealing seam 13 are combined with the triangular sealing tool 18 for the oblique bottom seam 4. The same applies to the transverse sealing tool 14 for the production of the cover-transverse sealing seam 15 and the oblique tool 17, which, however, only serves to produce the oblique cover seam 7. Separate sealing tools 17a are provided for the longitudinal seams 9 of the spout 8. For punching out the rectangular waste 19a on both sides of the spout 8 serve correspondingly shaped cutting knife 20a. The vertical sealing tools 23 now extend over the full bag height.

According to Figure 7, for the manufacture of a bag e.g. 1, the V-shaped base 2 and the side surface 1 'with the attachment for the spout 8 from a film web 28 and the other side surface 1 and the V-shaped cover 6 with the corresponding spout attachment from a second film web 29 are folded.

According to FIG. 8, the production of a bag, which is basically the same, takes place from a first film web 30 for the side face 1, on a second film web 31 for the V-shaped bottom 2, and from a third film web 32 for the V-shaped lid 6 with the attachment for the spout 8 and a fourth film web 33 for the other side surface 1 'with the corresponding spout approach.

The bottom gusset bag shown in FIG. 9 essentially corresponds to that according to FIG. 5, however, in this modified embodiment, two or more longitudinal seams 3 arranged next to one another at a distance are provided, the longitudinal strips 34 formed in this way being folded over to one another inwards onto the side face 1 and glued to it are.

FIG. 10 pulls a bottom gusseted bag which corresponds to a doubling of the bag according to FIG. 9. This modified bag is divided into two chambers 35, 36 by an intermediate floor 37. The lower chamber 36 has its own spout 8a.

The embodiment shown in FIG. 11 differs from that according to FIG. 10 only in that each of the two chambers 35, 36 is assigned two spouts 8, 8b and 8a, 8c.

According to FIG. 12, the bag shown in FIG. 10 is produced from five film webs, of which the first four correspond to those of FIG. 8, while the fifth film web 38 forms the V-shaped intermediate floor 37.

FIG. 13 shows the pre-folding for producing a bag according to FIG. 11 and essentially corresponds to the illustration according to FIG. 12, only the film web 30 forming the side surface 1 being exactly as wide as the film web 33 forming the side surface 1 ′ Film web 31 now forms an isosceles V just like film web 32 forming cover 6.

FIGS. 14 and 15 show tools for producing a bag according to FIG. 9, the production of the longitudinal strips 34 being important. There are two pairs of clamping jaws arranged at a distance from one another, between which the pre-folded film 11 1 lies. One pair of parts represents a type of drawing die 39 and the other pair of parts represents a type of hold-down device 40. In the latter, a pressure stamp 41, which can be displaced perpendicularly to the plane of the film 11, is arranged, in which a separating knife 42 is provided in the center. The drawing die 39 consists of an outer fixed part and of inner displaceable pressure bars 39a, between which a welding or sealing jaw 43 which works in the opposite direction to the pressure stamp 41 and serves to produce the longitudinal seams 3 is arranged. This forms, on the one hand, the counter bearing for the separating knife 42 and, on the other hand, serves as a carrier for pivotable pressure flaps 44 which, in the pivoted-out position, project into the displacement area of the pressure strips 39a. In the free edge area of the fixed part of the drawing die 39, inwardly directed glue spray nozzles 45 are arranged.

FIG. 15 shows the individual phases in the production of the longitudinal strips 34 on a bag according to FIG. 9. According to FIG. A), in the starting position, all the device parts are spaced from one another, so that the pre-folded film web 11 can be pulled through. According to Figure b), the drawing die 39 and the hold-down device 40 are then moved against each other, the hold-down device and the fixed part of the drawing die 39 serving to adjust the film web 11. Then the plunger 41 with its separating knife 42 and the welding or sealing jaws 43 are moved against each other. This results in a separation of the film web 11 on the one hand and the production of the longitudinal seams 3 on the other hand. According to Figure c), the pressure ram 41 then moves back into the drawing die 39 with the welding or sealing jaws 43 receding and thereby folds the previously sealed longitudinal strips 34 at right angles inside. According to Figure d), the pressure bars 39a of the drawing die are then withdrawn, the welding or sealing jaw 43 moves forward again, its pressure flaps 44 are swung out and glue is sprayed against the angled longitudinal strips 34 from the glue spray nozzles 45. Figure e) shows that when the welding or sealing jaws 43 are advanced further, their pressure flaps 44 locked in the pivoted-out position press the longitudinal strips 34 firmly against the film web, which form the side face 1 in the finished bags. Figure f) shows the welding or sealing jaws 43 with the pressure flaps retracted; in addition, the pressure bars 39a are moved back into their starting position.

In this device, the pressure stamp 41 can also be equipped with welding or sealing jaws. However, it is also possible, as indicated in FIG. 14, for the longitudinal seams 3 to be sealed using the conventional vertical sealing tools 23, so that the tools 41, 43 are used exclusively for folding and pressing the longitudinal strips 34 of the bag.

FIG. 16 shows the tools for producing a bag according to FIG. 10, while FIG. 17 shows the sealing or weld seams Production of a bag according to Figure 11 can be seen.

Claims (13)

1. Bag with a fold in the bottom with two lateral faces (1,1'), with a v-shaped bottom (2) folded inwards, with longitudinal seams (3) which extend at least until the v-shaped fold and with at least four lateral v bottom seams (4) which are inclined, and which combine only one lateral face (1,1') each with a side of the v of the bottom (2), showing a starting point (5) on the corresponding longitudinal seam (3) on the level of the fold in the bottom, characterized in that the bag is formed of at least two pieces of foil (28, 29), showing a cover (6) which is formed according to the bottom (2), in case of which four lateral cover seams (7) are inclined according to the bottom seams and that one lateral face (1') as well as the adjacent side of the v of the cover (6) are prolonged beyond the transversal brim of the cover and form commonly a filling respectively discharge socket (socket 8) with longitudinal seams (9).

2. Bag according to claim 1 characterized in that the longitudinal seams (3) also extend over the height of the bottom (2) as well as over the height of the cover (6), combining in this area only one lateral face (1,1') each with a side of the v of the bottom (2) respectively of the cover (6).

3. Bag according to claim 2, characterized by two or several longitudinal seams (3) each which are arranged with distances side by side, whereby the longitudinal strips (34) formed in this manner are folded inwards to the one or the other lateral face (1,1') and are glued with the same.

4. Bag according to claim 3, characterized in that a reinforced adhesive ,tape is inserted between the longitudinal strips (34) folded inwards and the corresponding lateral face (1.1').

5. Bag according to claim 1, characterized in that the four triangular sections (21) which are formed by the laterally inclined bottom seams (4) together with the longitudinal edge (brim) as well as the corresponding triangular sections (19) of the cover (6) are separated.

6. Bag according to one of the preceding claims characterized in that the v-shaped bottom (2) as well as one lateral face (1') with the socket stud are folded out of a piece of foil (28) and that the other lateral face (1) as well as the v-shaped cover (6) with socket stud are folded out of a second piece of foil (29).

7. Bag according to one of the claims 1 to 5 characterized in that the one lateral face (1) consists of a first piece of foil (30), the v-shaped bottom (2) consists of a second piece of foil (31), the v-shaped cover (6) with socket stud consists of a third piece of foil (32) and the other lateral face (1') with socket stud consists of a fourth piece of foil (33).

8. Bag according to claim 7 characterized by an intermediate bottom (37) consisting of a fifth piece of foil (38) which subdivides the bag into two chambers (35, 36) and by a second socket (8a) in the bottom (2).

9. Bag according to claim 8 characterized in that the intermediate bottom (37) is formed as filter. _

10. Device for the production of the longitudinal stripes, which are folded, of a bag according to claim 3 or 4 characterized by the following features:

a) Two pairs of clamping jaws which are arranged side by side with distance to each other, between which the foil can be clamped which is already folded, whereby the one part of the pair is kind of a pulling matrix (39, 39a) and the other part of the pair is kind of a blank- holder (46),

b) a ripping knife (42) which is vertically movable with regard to the level of the foil as well as a punch (41) are arranged in the blank- holder (40);

c) the pulling matrix (39) shows internal movable pressing reglets (39a);

d) heat sealing or sealing jaws (43) for the production of the longitudinal seams (3), with pressing lids which can be swung out, projecting into the moving range of the pressing reglets (39a) when they are swung out, which work in opposite direction to the punch (41), are arranged in the pulling matrix (39).

11. Device according to claim 10 characterized in that glue sprinkle nozzles (45) which are directed inwards are arranged in the free range of the brim of the stationary part of the pulling matrix (39).

12. Device according to claim 10 or 11 characterized in that the ripping knife (42) is provided in the punch (41 ).

13. Device according to claim 10, 11 or 12 characterized in that heat sealing or sealing jaws (43) form the counter support for the ripping knife (42).

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