EP4129640A1 - Folding wedge device for a bag packaging machine - Google Patents

Abstract

Folding wedge device (1) for a bag packaging machine for continuously adjusting a bottom fold of a bag, comprising: a feed area (3) for continuously feeding a flat packaging film; a discharge area (6) opposite the feed area for feeding out the packaging film folded in the middle by means of the folding wedge device, a folding wedge (8) with two folding wedge strips (9) running towards one another in a wedge shape from the feed area to the discharge area for deflecting the packaging film; a counter point (10) arranged in the conveying direction of the packaging film behind the folding wedge strips for inserting the bottom fold between the packaging film sections folded on top of one another in the middle, the folding wedge strips having end sections (12) pointing towards the counter point and a lateral distance between the end sections of the folding wedge strips being infinitely adjustable.

Description

The invention is based on a folding wedge device for a bag packaging machine with a feed area for the continuous feeding of a flat packaging film, a discharge area opposite the feed area for discharging the packaging film folded in the middle by means of the folding wedge device, a folding wedge with two folding wedge strips running towards one another in a wedge shape from the feed area to the discharge area for deflecting the Packaging film, a counter-point arranged in the conveying direction of the packaging film behind the folding ledges for inserting a bottom fold between the packaging film sections folded over one another in the middle, the folding ledges having end sections pointing towards the counter-point. A folding wedge is known for example from CH 377183 A .

To produce a bottom fold on a packaging bag, format-dependent parts must be provided in pairs on the folding wedge. In order to change the dimensions of the bottom fold, the size of which particularly determines the footprint of the bag, in previous solutions a format part at the tip of the folding wedge and a counter-top inserting the bottom fold must be exchanged and/or positioned accordingly.

However, this replacement or repositioning of the format parts is expensive and labor-intensive, particularly in the case of frequent changes of bags to be produced with differently formed bottom folds on a packaging bag machine with a folding wedge.

It is therefore the object of the present invention to improve a folding wedge in such a way that the production of packaging bags with different bottom fold dimensions is simplified.

The object is achieved with a device having the features of independent claim 1.

Accordingly, it is provided that a lateral distance between the end sections of the folding wedge strips can be continuously adjusted. The packaging foil can Folding wedge device are fed in a horizontal orientation over the feed area. The feed area can have a conveyor and/or deflection roller, by means of which the film web is guided under the folding wedge. Those skilled in the art will recognize that the film may be fed in other orientations and that what matters is the orientations of the feed relative to the orientation after exit. In the conveying direction of the packaging film, the folding wedge can have a gradient, while the direction of movement of the film web guided past the folding wedge can be horizontal. When the film is guided past the folding wedge strips, the film can first be deflected at its outer edges in the conveying direction into a vertical alignment in the direction of the upper side of the folding wedge. In the further course of the folding wedge strips, the deflection can continue to move towards the center of the film. If no bottom fold is provided, when the film web reaches the end of the folding wedge, i.e. when it reaches the end sections of the folding wedge strips, the latter is folded in the middle, with the end sections forming a point in this case, which is arranged in the fold of the film web. After passing the end sections of the folding wedge strips, the film web leaves the folding wedge, with the case that a bottom fold is provided, the distance between the end sections corresponds to the width of the packaging film section which is provided for inserting the bottom fold. This packaging film section stretched out by the end sections can then be guided over the counterpoint, which inserts the packaging film section between the opposing vertical packaging film sections deflected by the folding wedge strips and thereby produces the bottom fold. In cross section, the packaging film can have a W-shape after it has left the folding wedge device through the outfeed device. The discharge device can be formed by two counter-rotating rollers or stationary guide elements, through the gap formed by which the film placed on top of one another is guided and folded. It can be provided that the lateral distance between the folding wedge strips can be continuously adjusted. It can be provided that when the lateral distance between the folding wedge strips is adjusted, the lateral distance is set uniformly over the entire extent of the folding wedge strips. Alternatively, it can be provided that the lateral distance between the end sections is achieved by twisting the folding wedge strips relative to one another.

Provision can also be made for the folding wedge strips to adjust the distance between the end sections along their main direction of extension can be moved linearly. In their original orientation, the folding wedge strips can be arranged at a predetermined angle to one another. When linearly moving along the main extension direction of the folding wedge strips, they can maintain the predetermined angle to one another. Provision can be made for the folding wedge strips to be moved relative to the infeed area or the outfeed area as a result of the linear movement. Provision can also be made for the folding wedge strips to be moved in relation to the tailstock in the linear process. Provision can thus be made for the distance between the end sections and/or between the folding wedge strips to be increased when these are moved linearly in the direction of the feed device. Furthermore, it can be provided that the distance between the end sections and/or the folding wedge strips is reduced when these are moved linearly in the direction of the outfeed device and/or the counter tip.

It is possible for the folding wedge device to have a carrier plate on which linear guides, for example guide rails or a carriage, are mounted for adjusting the folding wedge strips. Alternatively, it is possible for the guide rails to be mounted on the folding wedge strips. A linear adjustment of the folding wedge strips relative to the carrier plate can be made possible by the linear guides.

It is also conceivable that the folding wedge strips can be adjusted by a motor by means of a drive arranged in particular between the folding wedge strips, in particular a spindle drive. Alternatively, it can be provided that each folding wedge strip has a separate drive. In the embodiment of a common drive, this can have a center guide which can be moved by the drive along the conveying direction of the packaging film. In contrast, the directions of movement of the folding wedge strips can each be at an angle to the conveying direction and parallel to the conveying plane. However, it can be provided that the folding wedge strips each have a movement component which extends along the conveying direction of the packaging film. The directions of movement of the folding wedge strips can be mirror-symmetrical with respect to the conveying direction of the packaging film. The central guide can each have lateral drivers which are set up to move the opposing folding wedge strips along their respective movement path.

Provision can be made for the folding wedge strips to be movable in the direction of the outfeed area in order to reduce the distance between the end sections. Due to their V-shaped or wedge-shaped alignment with one another, the distance between the end sections can be reduced when the folding wedge strips are moved in the direction of the outfeed area. It can therefore be provided that the lateral distance between the folding wedge strips decreases from the feed area in the direction of the outfeed area.

Accordingly, it can be provided that the folding wedge strips can be moved in the direction of the feed area in order to increase the distance between the end sections.

In addition, it can be provided that the counter-tip has two counter-tip strips, which converge in a wedge shape in the conveying direction of the packaging film, for inserting the bottom fold. While the film is guided along an underside of the folding wedge and the folding wedge strips have deflection edges pointing towards the underside of the folding wedge, the packaging film is guided along the upper side of the counter-tip to insert the bottom fold between the side walls of the bag, so that the deflection edges of the counter-tip strips correspond have deflection edges pointing to the upper side of the counter tip.

In particular, it can be provided that the folding wedge and the counter-point are aligned with one another in such a way that the end sections of the folding wedge meet the counter-point at an angle in a contact area, preferably forming a film gap of 0.1-2 mm, preferably 1 mm, with it. The contact area can be linear. As a result, it can be provided that the tip of the folding wedge rests against a surface of the counter tip. It can be provided that the counter tip strips of the wedge-shaped counter tip have a spacing on a section of the counter tip which corresponds to the maximum adjustable spacing of the end sections of the folding wedge strips. Provision can furthermore be made for the counter-pointing strips of the wedge-shaped counter-point to have a spacing on a section of the counter-point which corresponds to the minimum adjustable spacing of the end sections of the folding wedge strips.

Furthermore, it can be provided that the angle between the folding wedge and the counter tip is approximately between 100° and 140°, preferably between 110° and 130°.

It can be provided that the tailstock is height-adjustable, in particular driven by a motor. As a result, when the end sections of the folding wedge strips are adjusted, the counter-tip can be tracked so that the contact area or the film gap between the end sections of the folding wedge strips and the counter-tip can always be set constant, regardless of the setting of the bottom fold dimensions. Thus, when the bottom fold is enlarged, the distance between the end sections of the folding gussets can be increased and the folding gussets can be adjusted accordingly in the direction of the feed device. The resulting enlargement of the film gap can thus be counteracted by adjusting the counter tip upwards. When setting a smaller bottom fold, this process can be carried out in reverse order. Alternatively it can be provided that the counter tip is adjustable along the conveying direction.

It can thus be provided that the counter-tip is adjusted downwards to reduce the bag fold dimensions.

Accordingly, provision can be made for the counter-tip to be adjusted upwards in order to increase the dimensions of the bag folds.

Provision can also be made for the folding wedge device to have a control device which is set up to control the drive device of the folding wedge strips and the drive of the counter tip in such a way that when the size of the bottom fold is adjusted, the end sections of the folding wedge strips are aligned with the counter tip strips in such a way that the lateral distance between the folding wedge strips essentially corresponds to the lateral distance between the counter pointed strips in the contact area. At the same time, the control device can control the drives in such a way that a constant film gap is formed between the end sections of the folding wedge strips and the counter-tip, regardless of the set bottom fold dimensions.

In addition, it can be provided that the folding wedge has an additional guide strip, which can be adjusted in particular by a motor, to support the packaging film between the end sections of the folding wedge strips. As a result, wrinkling of the film in this area can be avoided. The guide strip can be arranged in such a way that it rests against the film gap and also forms it. The tracking of the film strip when adjusting the bottom fold dimensions can be based on the adjusted folding wedge strips, so that these are aligned in the conveying direction at the height of the end sections.

Provision can be made for the packaging film to extend in front of the infeed area essentially perpendicularly to the packaging film behind the outfeed area.

Fig. 1

eine Faltkeileinrichtung zur Herstellung von Verpackungsbeuteln ohne Bodenfalte;

Fig. 2

eine Querschnittsansicht einer Faltkeileinrichtung mit fest verbauter Keilspitze und Gegenspitze;

Fig. 3

eine Ansicht einer Ausführungsform eines Faltkeils mit verstellbarer Keilspitze und verstellbarer Gegenspitze im Zustand zur Erzeugung einer großen Bodenfalte;

Fig. 4

eine Ansicht der Ausführungsform des Faltkeils von Fig. 3 mit verstellbarer Keilspitze und verstellbarer Gegenspitze im Zustand zur Erzeugung einer kleinen Bodenfalte; und

Fig. 5

eine Gesamtansicht einer Ausführungsform einer erfindungsgemäßen Faltkeileinrichtung im Zustand zur Erzeugung einer kleinen Bodenfalte.

Further details of the invention are explained with reference to the figures below. It shows:

1

a folding wedge device for the production of packaging bags without a bottom fold;

2

a cross-sectional view of a folding wedge device with a permanently installed wedge tip and counter tip;

3

a view of an embodiment of a folding wedge with an adjustable wedge tip and an adjustable counter tip in the state for generating a large bottom fold;

4

a view of the embodiment of the folding wedge of 3 with adjustable chisel tip and adjustable counter-tip in condition to create a small bottom fold; and

figure 5

an overall view of an embodiment of a folding wedge device according to the invention in the state for generating a small bottom fold.

In the figure 1 The folding wedge device 1 shown serves to illustrate the process of producing a packaging film 22 folded in the middle without a bottom fold and accordingly has no elements for producing one. The Packaging film 22 is fed to the folding wedge device 1 by a feed device 3 in the conveying direction X, then guided past the folding wedge 8 and then fed out of the folding wedge device 1 by a discharge device 6 . In the region of the feed device 3 , the packaging film 22 has a plane alignment which is perpendicular to the plane alignment of the packaging film 22 behind the outfeed device 6 . In the area of the feed device 3 , the packaging film 22 is guided flat under the folding wedge 8 by means of a feed roller 4 arranged in front of the folding wedge 8 . The film 22 then passes the folding wedge 8, which tapers in the conveying direction X, on which the film 22 is continuously deflected into a vertical alignment, starting from its outer edges in the direction of the center of the film, around folding wedge strips 9 arranged on the side edges of the folding wedge 8. The folding wedge 8 has a carrier plate 13 to which the folding wedge strips 9 are attached. In the exemplary embodiment shown, the film web is folded onto one another completely in the middle, that is to say in half, at the point of the wedge tip immediately before it reaches the discharge device 6 . This point marks the meeting point 20 of both bag walls. The film web 22 folded in this way, consisting of two deflected film sections 19 , is then guided through two opposing delivery rollers 7 forming a delivery gap in order to stamp out the fold and then guided out of the folding wedge device 1 .

In the 2 The cross-sectional view shown of a folding wedge device 1 illustrates the process of producing a centrally folded film web 22 with a bottom fold 2. In the conveying direction X, the packaging film web is guided from the feed side 3 around the feed roller 4 under the folding wedge 8 and in its course on the folding wedge strips on both sides 9 deflected into a vertical orientation, so that the vertical sections move exclusively in the conveying direction X. At the lower end of the folding wedge 8, the folding wedge strips 9 have end sections 12, which are laterally spaced apart from one another in the direction perpendicular to the plane of the drawing. When these end sections 12 are reached, the first deflection process of the film 22 is complete, so that two lateral deflected sections 19 are opposite one another and a horizontal film section with a width corresponding to the lateral spacing of the end sections 12 is arranged between them. The lower end of the folding wedge 8 is now followed in the conveying direction X by a likewise wedge-shaped counter point 10 which is arranged at an angle α to the folding wedge 8 . A film gap 18 is formed between the end sections 17 of the folding wedge strips or the lower end of the folding wedge 8 and the counter tip 10, through which the film is guided. The film section horizontal in the area of the film gap 18 is now also folded in the middle in the course of the counter-point 10, also continuously starting from the sides of the section in the area of the film gap 18 up to the center of the film web 22 in the area of the point of the counter-point. However, this second deflection process takes place in the opposite direction to the first deflection process, so the horizontal film section is inserted between the vertical film sections 19 as a bottom fold. At point 20, that is to say immediately after leaving the counter-point, the vertical film sections 19 meet and are then guided out of the folding wedge device 1 by the rollers 7 of the outfeed area, which rotate in opposite directions.

3 shows an embodiment of the folding wedge device according to the invention with a detailed view of the area where the folding wedge strips 9 and the counter tip 10 meet. The folding wedge strips 9 can be linearly adjusted along their main extension direction E along the folding wedge 8 by means of a center guide 21 that can be adjusted by a motor-driven spindle 15 . Due to the fact that the folding wedge strips 9 are mounted at an angle to one another on the folding wedge 8, the distance a between the end sections 12 of the folding wedge strips 9 can be infinitely regulated. The end sections are followed by the formation of the film gap 18 and at an angle α to the folding wedge 8, the counter point 10, which is wedge-shaped and has a point which opens directly into the gap between the outfeed rollers 7 or guide segments. The counter point 10, along which the film 22 is guided along the upper side of the counter point 10, has corresponding to the folding wedge strips 9 counter point strips 11, on which the film guided past is deflected. The tailstock 10 can be adjusted in height by means of a spindle drive 16 . In the contact area 17, i.e. in the area of the film gap 18, between the counter point 10 and the end sections 12 of the folding wedge strips 9, the counter tip strips 11 of the counter point 10 have a lateral distance b, which corresponds to the lateral distance a between the end sections 12 of the folding wedge strips 9. In the illustration shown, the folding wedge device 1 is set to produce bags with a large bottom fold 2 . On the one hand, this means that the folding wedge strips 9 are moved away from the outfeed area 6 and accordingly produce a large distance a between the end sections 12 . On the other hand, the tailstock 10 is adjusted upwards in order to compensate for the vertical adjustment component of the folding wedge strips 9. This means that, on the one hand, a constant film gap 18 be generated. On the other hand, the folding wedge strips 9 and the counter tip 10 can always be adjusted to one another in such a way that the distance a corresponds to the distance b in each case.

4 shows the already in 3 shown embodiment of the folding wedge device 1 in the state for producing a small bottom fold 2. For this purpose, the folding wedge strips 9 are moved far in the direction of the discharge device 6, so that the end sections 12 have a small distance a. In contrast, the counter tip 10 is moved far down, so that the distance b between the counter tip strips 11 in the contact area 17 between the end sections 12 and the counter tip 10 is also small and corresponds to the distance a. The film gap 18 has the same gap width as that in 3 on. Good to see in 4 are the adjustment directions of the individual components. The tailstock 10 can be adjusted in height along the adjustment direction G. The center guide 21 moving the folding wedge strips 9 can be adjusted along an adjustment direction M along the conveying direction X. The adjustment directions E of the folding wedge strips 9 resulting from an adjustment of the center guide 21 run at an angle to one another along the folding wedge sides.

figure 5 shows an overall view of an embodiment of the folding wedge device 1. On the feed side 3 there is a feed roller for introducing the packaging film web 22 under the folding wedge 8 or under the folding wedge strips 9, which are each connected to a carrier plate 13 via linear guides 14 and are continuously adjustable along the folding wedge sides can become. A motorized spindle drive 15 is used to adjust the central guide 21, which entrains the folding wedge strips 9 arranged at the side of the central guide 21 via drivers. At the lower end of the folding wedge strips 9, their end sections 12 point in the direction of the opposite tip 10, which is arranged at an angle to the folding wedge 8, and form a film gap 18 together with this. The counter point 10 has counter point strips 11 for deflecting the film section provided for the bottom fold 2 . The tailstock 10 can be adjusted in height by a spindle drive 16 . After leaving the tailstock, the packaging film, which is then folded, is guided out of the folding wedge device through the discharge area 6 . The tailstock 10 can be adjusted in height by a spindle drive 16 .

The features of the invention disclosed in the above description, in the drawings and in the claims can be essential for the realization of the invention both individually and in any combination.

Reference list:

1

folding wedge device

2

trained bottom fold

3

feeding area

4

feed roll

5

packaging film

6

execution area

7

outfeed rollers

8th

folding wedge

9

folding wedges

10

counterpoint

11

counter pointing strips

12

end sections

13

backing plate

14

linear guide

15

Spindle drive folding wedge strips

16

Spindle drive counter tip bars

17

contact area

18

foil gap

19

deflected foil section

20

Meeting point of the deflected film sections

21

center guide

22

packaging film web

a

lateral distance between the end sections

b

lateral distance between the counter pointing strips

X

conveying direction

E

Main direction of extension and direction of movement of the folding wedge strips

M

Direction of movement center guide

G

Direction of movement of the opposite apex

a

Angle between folding wedge and heel

Claims (15)

Folding wedge device (1) for a bag packaging machine for continuously adjusting a bottom fold dimension of a bag, having a feeding section (3) for continuously feeding a flat wrapping film (22); a discharge area (6) opposite the feed area (3) for discharging the packaging film (22) folded in the middle by means of the folding wedge device (1), a folding wedge (8) with two folding wedge strips (9) running towards one another in the shape of a wedge from the infeed area (3) to the outfeed area (6) for deflecting the packaging film (22); a counter-point (10) arranged behind the folding wedge strips (9) in the conveying direction (X) of the packaging film (22) for inserting the bottom fold (2) between the packaging film sections folded on top of each other in the middle, the folding wedge strips (9) having end sections (12 ) exhibit; characterized in that a lateral distance (a) between the end sections (12) of the folding wedge strips (9) is continuously adjustable. Folding wedge device (1) according to Claim 1, in which the folding wedge strips (9) can be moved linearly along their main direction of extent in order to set the distance (a) between the end sections (12). Folding wedge device (1) according to claim 1 or 2, wherein the folding wedge device (1) has a carrier plate (13) on which linear guides (14) for adjusting the folding wedge strips (9) are mounted. Folding wedge device (1) according to one of Claims 1 to 3, the folding wedge strips (9) being motor-adjustable by means of at least one drive (15) arranged in particular between the folding wedge strips (9), in particular a spindle drive. Folding wedge device (1) according to one of Claims 1 to 4, the folding wedge strips (9) being displaceable in the direction of the outfeed region (6) in order to reduce the distance (a) between the end sections (12). Folding wedge device (1) according to one of Claims 1 to 5, the folding wedge strips (9) being movable in the direction of the feed region (3) in order to increase the distance (a) between the end sections (12). Folding wedge device (1) according to one of Claims 1 to 6, the counter-point (10) having two counter-pointed strips (11) running towards one another in a wedge shape in the conveying direction (X) of the packaging film (22) for inserting the bottom fold (2). Folding wedge device (1) according to one of the preceding claims, in which the folding wedge (8) and the counter tip (10) can be aligned with one another in such a way that the end sections (12) of the folding wedge (8) are in a contact area (17) forming a film gap (18 ) obliquely meet the counter tip (10), wherein the film gap (18) preferably has a gap width of about 0.1-2 mm, preferably 1 mm. Folding wedge device (1) according to one of the preceding claims, wherein the angle (a) between the folding wedge (8) and the counter tip (10) is approximately between 100° and 140°, preferably between 110° and 130°. Folding wedge device (1) according to one of the preceding claims, in which the counter tip (10) is height-adjustable, in particular motor-driven. Folding wedge device (1) according to one of the preceding claims, in which the counterpoint (10) is adjustable downwards in order to reduce the bag fold dimension. Folding wedge device (1) according to one of the preceding claims, in which the counterpoint (10) can be adjusted upwards in order to increase the bag fold dimension. Folding wedge device (1) according to one of Claims 10 to 12, the folding wedge device (1) having a control device which is set up to control the drive device (15) of the folding wedge strips (9) and the drive (16) of the counter tip (10) in this way that when the size of the bottom fold (2) is adjusted, the end sections (12) of the folding wedge strips (9) are each aligned with the counter tip strips (11) in such a way that the lateral distance (a) between the folding wedge strips (9) essentially corresponds to the lateral distance (b) between the counter tip strips (11) in the contact area (17). Folding wedge device (1) according to one of the preceding claims, wherein the folding wedge (8) has an additional motor-adjustable guide strip to support the packaging film (22) between the end sections (12) of the folding wedge strips (9). Folding wedge device (1) according to one of the preceding claims, in which the packaging film (22) in front of the feed area (3) extends essentially perpendicularly to the packaging film (22) behind the outfeed area (6).

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