EP0169464B1 - Device for producing and filling bags - Google Patents

Description

The invention relates to a device for the production and filling of bags, which are provided with - preferably stiff - label strips and are produced from a half-tube consisting of plastic film, by means of separating weld seams which are attached transversely to its extension - by means of appropriate welding jaws - into the first open bags on the open side of the half-tube and after filling by seal welding - by means of appropriate seal-welding jaws - the bags are divided. Such a device is e.g. B. is known from US-A-3 319 538.

Appropriate devices are available on the market. However, the economy of the known devices is unsatisfactory insofar as a relatively high outlay is required to apply the labels.

In some cases, the labels are even attached manually to already filled bags by placing a roof-like folded cardboard strip with labeling over an edge of the bag and attaching it there using staples. If the filling of the bag has a greater weight and the bag is hung on hooks or the like by means of an opening in the label for the presentation, the bag looks slightly unsightly because the filling weight tries to detach the bag from the fastening clips on the label.

It is also known to mechanically weld cardboard strips folded like roofs by heating a plastic coating located on the inside of the cardboard fold to the already filled bags. Here, however, comparatively expensive special cartons are necessary, the thickness of the carton cannot be chosen freely because the heating of the plastic coating for welding the cartons to the bags must take place through the corresponding heat-resistant carton.

In addition, there are devices which, after manufacture of bags open on one side, first insert a label into the bag and then weld the bag walls above the label to one another while shortening the bag, so that the label is captively enclosed by the film forming the bag. The goods to be packed are then filled into the bag and the bag opening is sealed by seal welding. This device is relatively difficult to convert to different bag sizes because the labels are inserted to different lengths with bags of different lengths and the sealing seam dividing the label receiving space from the rest of the bag must be made at a correspondingly different distance from the bag opening. In addition, this sealing seam must be applied with relatively great care if it is to be avoided that filling material can get into the label receiving space during the subsequent filling of the bag.

It is therefore an object of the invention to provide a device which allows bags with labels made of any material, in particular normal cardboard, to be produced in a particularly simple manner, in which case the device can in particular be easily converted for different bag sizes.

This object is achieved in that by means of a - arranged as part of the device - form shoulder for the production of the half-tube, both edge strips of a film web which can be drawn over the form shoulder, with the formation of two U-folds which overlap one another with their free edges, can be folded over, that the labels are conveyed by means of a label feed member synchronized with the advance of the half-tube moving along a conveyor line through its film-side end opening into one fold (label fold) with the free edge covered on the outside by the other fold, and that the separable weld seams can be attached behind each inserted label - by means of the separating welding jaws - across the entire width of the other fold (bag fold) are extended into an area of the label fold between successive labels - but with the exception of a partial width of the label fold.

According to the invention, the bag fold can have any dimensions transversely to the forward direction without this having any influence on the label feed because the label is inserted at the same place in each case.

In addition, a pouch tape is inevitably formed in the manufacture of the pouches in that adjacent pouches are connected to one another in a band-like manner over a partial area of the label fold. The labels arranged in the label fold stiffen the band-shaped connection in sections in each case to a length corresponding approximately to the dimension of the bag opening in the forward direction. This gives the bag band a chain-like structure with relatively stiff chain links formed by the labels, which are flexibly connected to one another via the partial areas of the label fold mentioned.

According to a preferred embodiment, it is provided that the separating welding jaws work synchronously with perforating jaws, which are arranged in continuation of the separating welding jaws in the region of the part width of the label fold which is recessed by the separating welding jaws in order to produce a perforation which continues in a line-like manner. This perforation has no influence whatsoever on the handling of the bag band, but facilitates the later separation of the bags from the bag band.

The label feed element is expediently designed or arranged that the labels can be advanced from a position outside the half-tube into a transfer position within the half-tube, from which the labels are taken along by frictional engagement with the label fold when the half-tube is advanced. Special measures for holding the labels in the label fold are therefore unnecessary.

In a structurally particularly simple manner, a channel comprising a label edge can be arranged as the feed element, in which the label can be moved into the transfer position by means of a stamp guided parallel to the channel.

In a particularly preferred embodiment of the device according to the invention, a light barrier is arranged in the forward direction behind the transfer position as part of a control of the intermittent feed of the half-tube, in order to advance the feed when the light path of the light barrier is released after passing the rear edge of a label in the forward direction with activation of the separating welding jaws Interrupt the execution of the separating weld seams and switch on again when the light path is interrupted again through the front edge in the forward direction of the next label pushed into the transfer position. With this type of feed control, the dimension of the bags in the feed direction is automatically adapted to the corresponding dimension of the labels. No measures are required to convert the device.

At a filling station for filling the bags, which is arranged in the forward direction after the separating welding jaws, the label fold can be guided on a curved web with a center of curvature on the side of the bag belt facing the free edges of the U-folds, in such a way that the web guiding elements provide the free one Try to press the edge of the label fold transversely to the direction of advance against the labels without grasping the free edge of the bag fold lifting off from the free edge of the label fold due to the curvature of the web.

In an advantageous embodiment, a blower with a blowing direction leading away from the label fold can be directed against the free edge of the bag fold in order to forcibly hold the edge of the bag fold in the lifted-off position by the blower flow trying to inflate the bag.

• Fig. 1 eine Seitenansicht des herzustellenden Beutelbandes,
• Fig. 2 ein Schnittbild der Beutel entsprechend der Schnittlinie 11-11 in Figur 1,
• Fig. 3 eine Seitenansicht der Vorrichtung,
• Fig. 4 eine Draufsicht auf die Vorrichtung,
• Fig. 5 eine Ansicht der Formschulter entsprechend dem Pfeil V in den Figuren 3 und 4 und
• Fig. 6 ein Schnittbild der Vorrichtung entsprechend der Schnittebene VI-VI in Figur 3 zur Darstellung der Trennschweißbacken.

For the rest, with regard to advantageous embodiments of the invention, reference is made to the claims and the following description, in which the invention is explained with reference to a particularly preferred exemplary embodiment shown in the drawing. It shows

• 1 is a side view of the bag band to be manufactured,
• 2 is a sectional view of the bag according to the section line 11-11 in Figure 1,
• 3 is a side view of the device,
• 4 is a plan view of the device,
• Fig. 5 is a view of the shape shoulder according to the arrow V in Figures 3 and 4 and
• Fig. 6 is a sectional view of the device according to the section plane VI-VI in Figure 3 to show the separating welding jaws.

The bags 1 shown in Figures 1 and 2 consist of a film, the edges of which are folded over to form a half tube such that a first fold 2 (label fold) and a second larger fold 3 (bag fold) are formed with overlapping edges, whereby the free edge of the bag fold 3 rests on the free edge of the label fold 2 from the outside. For the division of the bags 1 from each other, there are separating weld seams 4, which extend over the entire bag fold 3 and an adjoining partial area of the label fold 2 and each connect the front and back of the folds 2 and 3 of each bag 1, but separate adjacent bags 1 from one another.

The separating weld seams 4 continue into perforations 5 arranged in a line, which facilitates tearing of the area of the label fold 2 connecting the bags 1.

In the label fold 2 of each bag 1, a label 6 made of cardboard or the like is accommodated, which is held in place on the one hand by frictional engagement at the separating weld seams 4, which somewhat encompass two opposite corners of the label 6, and by a sealed weld seam 7, which are tight runs below the label transversely to the separating weld seams 4 and connects the free edges of the folds 2 and 3 to one another and to the opposite common side of these folds. If necessary, it is also sufficient if the sealing weld 4 is applied just below the free edge of the label fold and only connects the opposite sides of the bag fold 3 to one another. In any case, the seal weld 7 closes the bag fold 3 in FIGS. 1 and 2 from above, so that the filling material (not shown) accommodated in the bag fold 3, which is introduced before the seal weld 7 is applied, is securely enclosed.

The bags 1 are produced from a plastic film 8 which is wound on a roll 9 in the device according to the invention shown in FIGS. 3 and 4. The plastic film 8 first runs over guide rollers 10, of which the roller 10 'is arranged resiliently, so that the roller 9 can be unwound at a constant speed, although the plastic film 8 runs intermittently through the device.

To form the half tube with the the cross-section shown in Figure 2, the film 8 is drawn over a shape shoulder assembly 11. This essentially consists of three pyramid-like guide surfaces 12 to 14. The lateral guide surfaces 13 and 14 are arranged such that their front edges in FIG. 3 leave a gap 15 visible in FIG. 5 between them. In addition, the end piece 14 'of the guide surface 14 is turned over in a U-shape in such a way that its free end in the view in FIG. 5 lies within the gap 15 and, according to FIG. 3, is directed obliquely downwards to the right.

The film 8, coming from the last guide roller 10 ″ in the direction of transport, initially runs over the lower guide surface 12 on which the film 8 lies flat. The two side edges of the film also lie flat on the guide surfaces 13 and 14, the on The side edge lying on the guide surface 14 also lies flat on the left side of the end piece 14 in Figure 5. If the side edges of the film rest on the guide surfaces 13 and 14 or the end piece 14 'in the manner mentioned, a slack area of the film forms 3, such that the film is drawn on the one hand around the front edges of the guide surfaces 13 and 14 delimiting the gap 15 and on the other hand around the front edge of the end piece 14 ' inevitably the half tube with cross section according to Figure 2, which subsequently in the horizontal direction (see FIG. 3) through the device is transported further.

For better guidance of the film through the gap 15, a guide bar 16 is arranged which is fastened in front of the shaped shoulder arrangement 11 in the transport direction of the film 8 and projects cantilevered through the gap at the lower end of the gap 5 in the horizontal direction.

Upper and lower pairs of belts 17 and 18 are arranged as a drive for the advance of the film or the half tube, which rotate on guide rollers 19 which are arranged such that the upper pairs of belts 17 between them the label fold 2 and the lower pairs of belts 18 between them Grip the region of the bag fold 3 adjacent to the label fold 2 and allow it to advance to the right in FIGS. 3 and 4 by frictional engagement when the guide rollers 19 are driven.

To insert the labels 6 into the label fold 2 formed by the end piece 14 'of the shaped shoulder arrangement 11, an insertion groove 20 is arranged which, parallel to the guide bar 16, passes through the gap 15 into the vicinity of a light barrier arrangement 22 by a label magazine 21 at the lower end of the end piece 14' . The labels 6 are pushed in the groove 20 by means of a pneumatically driven stamp 23 with interrupted advance of the film or the half-tube (guide rollers 19 and thus the pairs of belts 17 and 18 stand still) in FIGS. 3 and 4 to the right until the in The direction of advance of the front edge of the label 6 interrupts the light path of the light barrier arrangement 22. Now the stamp 23 stops or runs back to capture the next label, while the advance of the film 8 or the half-tube switches on and the label 6 located in the take-over position on the light barrier arrangement 22 is carried along by frictional engagement with the label fold. As soon as this label, which has just been taken along, clears the light path of the light barrier arrangement 22 again as it passes by its rear edge, the film advance is interrupted again.

Now another label is again pushed up to the takeover position, i. H. to a position in which the front edge of this label interrupts the light path of the light barrier arrangement 22.

During these interruptions in the film advance controlled by the light barrier arrangement 22, a separating welding jaw arrangement 24 is also actuated to produce the separating weld seams 4. In this case (cf. FIG. 6), a separating welding jaw 25 is pressed by means of a pneumatic unit 26 against a fixed counter jaw 27 covered with silicone rubber, until the respective separating weld seams 4 are made and the bag fold 3 has been cut between these seams 4.

At the same time, a pneumatic unit 28 actuates a perforating knife 29, which is pressed against a perforated jaw 30 covered with rubber. The perforations 5 are thus produced in a continuation of the separating weld seams 4.

By controlling the film advance by means of the light barrier arrangement 22, the dimensions of the bags 1 in the forward direction are automatically of the corresponding length. Labels 6 adjusted.

A punching device 31 is arranged in the forward direction behind the separating welding jaw arrangement 24, with which the label fold 2 and the label 6 of each bag 1 located therein can be perforated to form a suspension opening or the like (see FIG. 1).

This punching device 31 is arranged to be displaceable in the forward direction of the film, so that the suspension opening can be attached at a desired point - generally in the middle of the bag. The punching device 31, like the separating welding jaw arrangement 24, is actuated when the film 8 is interrupted, wherein the punching device 31 can again be switched on - indirectly or directly - by the light barrier arrangement 22. A filling station 32 for filling the bags is arranged between the pairs of belts 17 and 18 in the manner shown in FIGS. 3 and 4. The filling station 32 can

if necessary, together with the pairs of belts 17 and 18, are displaced in the forward direction in order to be able to adjust the position of the filling station 32 in such a way that exactly one bag is inside the filling station 32 when the advance is interrupted.

At the filling station 32, a curved guide plate 33 with pressure rollers 34 is arranged such that the label fold 2 runs between the guide plate and the pressure rollers 34, without the bag fold 3 being able to be reached by the guide plate 33. The guide plate 33 rests with its convex side on the left side of the label fold 2 in FIG. 2, so that the same is accordingly pushed away (in FIG. 2) to the right. The free edge of the bag fold 3 tries to stand out from the free edge of the label fold 2, so that a bag opening 35, shown schematically in FIG. 4, is formed. In addition, an air jet is directed from above against the free edge of the bag fold 3 by means of a blower 36, so that the bag opening is inevitably opened or kept open, since the air jet tries to inflate the bag. The material to be filled can now be filled into the bag by means of a feed or portioning device, not shown.

After passage through the filling station 32 _Qu r .-. The bag or the bag tape htaufen a seal welding apparatus 37, the movable jaw is operated for the production of visible in Figures 1 and 2 sealing weld 7 by means of a pneumatic unit 38th

Now the filled and closed bags only have to be separated from each other. For this purpose, a bag separator 39 with pneumatically operated clamping jaws 40 is used, which are able to hold the bag strand in front of and behind a perforation 5 in such a way that a simultaneously operated separating slide 41 can cut through the perforation 5.

The separated and filled bags can now be fed to a transport container (not shown) or the like.

Claims (8)

1. Apparatus for the manufacture and also filling of bags (1) which are provided with preferably stiff label strips (6) and are manufactured from a semi-finished hose consisting of plastic foil (8) in that the semi-finished hose is subdivided by partition welding seams (4) formed transverse to its extent - by means of corresponding welding jaws (24) - into bags which are initially open at the open side of the semi-finished hose and which are closed after filling by a sealing weld (7) - by means of corresponding sealing weld jaws (37) -, characterised in that by means of a forming shoulder arrangement (11) for manufacturing the semi-finished hose - provided as part of the apparatus - both edge strips of a foil web (8) which can be drawn over the forming shoulder arrangement (11) can be folded over to form two U-folds (2, 3) the free edges of which overlap; in that the labels (6) are insertable by means of a label supply device (20, 23) synchronously with the advance of the semi-finished hose, which is moved on further along a conveyor path, through the end opening of the semi-finished hose at the foil web end into the one fold (label fold 2) with the free edge which is covered over at its outer side by the other fold (bag fold 3); and in that the partition weld seams (4) which can be provided behind each inserted label (6) by means of the partition welding jaws (25) extend over the full width of the bag fold (3) up to and into a region of the label fold (2) between sequential labels (6) - however leaving out part of the width of the label fold (2).

2. Apparatus in accordance with claim 1, characterised in that the partition welding jaws (25) operate synchronously with perforating jaws or knives (29, 30) which are arranged in continuation of the partition welding jaws (25) in the region of the part width of the label fold (2) spared by the partition welding jaws (25) in order to manufacture a perforation (5) which forms a linear continuation of the partition welding seams (4).

3. Apparatus in accordance with one of the claims 1 or 2, characterised in that the labels (6) are advancable by means of the label supply device (20, 23) from a position outside of the semi-finished hose into a transfer position (at 22) within the semi-finished hose from which the labels (6) are moved along by frictional engagement with the label fold (2) by the latter during the advance of the semi-finished hose.

4. Apparatus in accordance with one of the claims 1 to 3, characterised in that a channel (20) engaging around a label edge is provided as the label supply device, with the label (6) being advancable inside the channel (20) into the transfer position (at 22) by means of a stamp or ram (23) guided parallel to the channel.

5. Apparatus in accordance with one of the claims 1 to 4, characterised in that a light barrier (22) is arranged behind the transfer position (at 22) in the direction of advance as a part of a control for the cyclical advance of the semi-finished hose, in such a way that on freeing of the light path of the light barrier (22) after the rear edge of the label (6), in the direction of advance, has passed by, the advance is interrupted while controlling the partition welding jaws (25) to execute the partition welding seam (4), and is switched-on again on subsequent renewed interruption of the light path through the front edge, in the direction of advance, of the next label (6) which is pushed into the transfer position (at 22).

6. Apparatus in accordance with one of the claims 1 to 5, characterised in that the label fold (2) is guided at a filling station (32), after the partition welding jaws (25) in the direction of advance, on a curved path with a centre of curvature on the side of the U-shaped folds facing the free edges of the U-shaped folds (2, 3), in such a way that the web guidance elements (sheet metal guide 33, contact pressure rollers 34) attempt to press the free edge of the label fold (2) against the label (6) transverse to the direction of advance, without engaging the free edge of the bag fold (3) which lifts from the free edge of the label fold (2) as a result of the track curvature.

7. Apparatus in accordance with claim 6, characterised in that, at the filling station (32), a fan (36) with a blowing direction leading away from the label fold (2) is directed against the free edge of the bag fold (3).

8. Apparatus in accordance with one of the claims 1 to 7, characterised in that a punch apparatus (31) is arranged after the partition welding jaws (25) in the direction of advance with the punch apparatus being capable of producing an opening which passes through the label fold and also through the respective label (6), for example for the later suspension of the bag (1).

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