EP3313655B1 - Apparatus, method and system for the careful pre-folding of pack sleeves - Google Patents

Description

The invention relates to a device for pre-folding package sleeves, comprising: at least two folding strips for pre-folding the gable surfaces and the triangular surfaces of the packaging sleeves, at least one folding block that can be inserted into the packaging sleeves, and at least one fold-back folder for folding back the triangular surfaces, the folding strips each having at least one contact surface for Have pre-folding of the gable surfaces, and wherein the folding strips are arranged on opposite sides of the folding block and are pivotably mounted.

In addition, the claimed invention does not cover a method for pre-folding packaging sleeves and a system for pre-folding packaging sleeves.

Packaging can be produced in different ways and from a wide variety of materials. A widespread possibility of production consists in producing a blank from the packaging material which usually has fold lines (also known as "crease lines"), from which a package jacket and finally a package are first formed by folding and further steps. This variant has the advantage, among other things, that the blanks are very flat and can therefore be stacked to save space. In this way, the blanks or packaging jackets can be produced at a different location than the folding and filling of the packaging jackets. Composites are often used as the material, for example a composite of several thin layers of paper, cardboard, plastic or metal. Such packaging is particularly widespread in the food industry.

Before the pack sleeves can finally be folded and closed, a so-called pre-folding often takes place. In order to reduce the folding forces required for the subsequent final folding, the individual layers of the composite materials are broken along the intended crease lines, which is why the term "pre-breaking" is also used. Pre-folding the pack sleeves also has other advantages. First of all, the pre-folding - in contrast to the final folding - can take place before the sterilization and / or the filling of the packaging sleeves, so that folding tools can also be used during the pre-folding, which are inserted into the interior of the packaging sleeves. In the case of pre-folding, it is therefore possible to have the folding tools attack the pack sleeves on both sides, that is to say from the inside as well as from the outside. For hygienic reasons, this is hardly possible after the sterilization and / or the filling of the pack sleeves. By using folding tools that engage on both sides, the pack sleeves can be pre-folded particularly precisely, in particular very precise fold edges can be produced. In addition, a certain folding direction can already be specified by the pre-folding, so that particularly simple tools can be used for the final folding. These simple tools can be fixed rails, for example, which fold over the pre-folded areas of the pack sleeves that are guided past the rails.

From the DE 25 20 404 B1 a generic device is known.

From the WO 02/00522 A1 a method is known for reducing the stresses in the area of the crease lines of packaging jackets. It is proposed that the material of the packing jacket be heated in the area of the scoring lines before folding. The heating should take place, for example, by hot air and make the material layers of the packing jacket more elastic and thus less prone to cracks. A disadvantage of this method, however, is that it requires a very large amount of energy to heat air and thus to heat the packing jackets. Another disadvantage is that excessive exposure to heat can result in discoloration or damage to the packing jacket.

From the U.S. 6,357,203 a device for pre-folding the gable surfaces of a package is known. The device described there is part of an overall system and the pre-folding of the gable surfaces should take place after the folding and closing of the bottom surfaces and before the packaging is filled. The device comprises two pivotably mounted arms and a mandrel that can be lowered into the packaging. Triangular flap elements are provided at the ends of the arms, the shape of which corresponds to the triangular surfaces in the area of the gable of the packaging. Two folding heads, each with a folding edge, are pivotably mounted on the mandrel. The triangular folding elements are intended to fold the triangular surfaces inwards, the fold lines being "broken" along the folding edges of the folding heads.

A disadvantage of the U.S. 6,357,203 known device is that no backfolders are provided. This has the consequence that the mandrel, which is arranged inside the pack jacket during the pre-folding, can only be pulled out of the pack jacket again with difficulty and, when pulled out, hits the inwardly folded gable areas. This can lead to damage to the inside of the packing jacket, which can cause the hygienic problems already described above.

In addition to the U.S. 6,357,203 known device, many other known devices and methods also pursue the goal of achieving fold edges as precisely as possible during the pre-folding. For this purpose, folding tools are often used which firmly clamp the pack jacket in the direct vicinity of the crease lines, so that the pack jacket is fixed in its position during the folding process. Although this has the advantage that creasing is prevented, it is associated with the disadvantage that cracks can occur in some layers of the packing jacket. The cracks occur in particular in places where several crease lines cross. This phenomenon occurs above all in the gable area and is also known as "creased cross breakage". As an undesirable consequence of this damage, the filled food could come into contact with non-sterile layers of the packaging jacket. for example with an inner layer of cardboard. The filled food could be contaminated in this way and would no longer be suitable for consumption.

Against this background, the invention is based on the object of designing and developing the device mentioned at the beginning and shown in more detail and the system mentioned at the beginning and shown in more detail in such a way that a particularly gentle and damage-free pre-folding of the packaging jackets can take place without increased use of energy.

A further object of the invention is to provide a pack jacket from which a folding block can be pulled out without damaging the inner surfaces of the pack jacket. In addition, the package jacket should form an opening that is optimal for the subsequent filling process and the subsequent sealing process.

This object is achieved in a device according to the preamble of patent claim 1 in that the back folder is attached to one of the folding strips.

The device is initially characterized by at least two folding strips for pre-folding the gable surfaces and the triangular surfaces of the pack jackets. The gable surfaces and the triangular surfaces are those surfaces which are arranged in the gable area of the pack jacket. The pre-folding can take place “actively” (that is to say through contact between the folding tool and the surface to be folded) or “passively” (that is to say without contact between the folding tool and the surface to be folded). For example, the folding strips can actively press the gable surfaces inwards, as a result of which the triangular surfaces are passively pressed outwards. In addition, at least one folding block is provided in the device, which can be inserted into the packaging jacket. This means that the folding block must be shaped and mounted in such a way that it can be inserted into one of the two openings of the package jacket - that is, into the top opening or into the bottom opening. The folding strips of the device should each have at least one contact surface for pre-folding the gable surfaces. The contact area is understood to mean that area which is in contact at least temporarily with the gable surfaces to be folded during the folding process.

According to the invention, the device comprises at least one back folder for folding back the triangular surfaces. The back folder is attached to one of the folding strips. If several back folders are provided, the back folders can be connected to or attached to the same or different folding strips. The purpose of the refold is to fold the pre-folded surfaces back a little. This has the advantage, for example, that the folding block can be pulled out of the pack jacket again in a particularly simple manner. In particular, damage to the insides of the pack jacket can be avoided, which can be caused, for example, by the often quite sharp-edged folding edges of the folding block. Preferably, the refolding does not achieve permanent refolding, but rather only a temporary retention of the pre-folded surfaces of the pack jacket. This has the advantage that the pre-folded surfaces are retained while the folding block is pulled out of the pack jacket and then moves back into the pre-folded position.

According to one embodiment of the device, the folding block is mounted so as to be linearly displaceable. A linearly displaceable mounting has several advantages: It can be implemented in a structurally simple and cost-effective manner and allows the folding block to be inserted precisely into the pack jacket, the edges of which usually also run linearly. The folding block is preferably mounted so as to be linearly displaceable in the vertical direction, that is to say at right angles to the transport path of the pack jackets, which typically runs horizontally.

Another embodiment of the device provides that the folding block has a web with a web width of less than 3 mm, in particular of less than 2 mm. In folding devices known from the prior art, the web surfaces are the During the pre-folding, packing sleeves are often pressed against the web of the folding block on both sides. Although this allows precise folding lines between the gable surfaces and the web surfaces, it has the disadvantage of placing a high load on the packaging jacket. This is due in particular to the fact that the web surfaces are clamped between the folding tool and the web, which results in an increased risk of crack formation. This risk can be countered by a particularly small web width in the specified area. The advantage of these narrow web widths is that the web surfaces are not pressed against the web during the pre-folding. Instead, the gap between the folding tool and the web is wider than the material thickness of the packing jacket.

According to a further embodiment of the device, it is provided that the folding block has two oppositely arranged folding edges for folding the gable surfaces. The folding edges serve the purpose of producing particularly precise fold lines. During the pre-folding, the material of the package jacket is folded "over" the folding edges of the folding block, whereby the course of the folding lines is predetermined and defined. Although this requires precise positioning of the folding block, it allows the generation of much more precise folding lines than would be possible with a pre-folding that uses the creased lines alone as a "folding aid".

For this embodiment of the device, it is further proposed that the length of the folding edges is at least 5% less than the length of the gable surfaces to be folded. The length of the folding edges can also be at least 10% less than the length of the gable surfaces to be folded. By making the folding edges shorter than the surfaces to be folded on them, a particularly gentle folding is made possible. This is due to the fact that the folded edges do not extend into the corners of the package jacket, but rather small free spaces remain there. On the one hand, the free spaces mean that the precision of the fold lines in this area is somewhat lower; on the other hand, however, they allow movement of the material of the packing jacket. The risk of cracking is significantly lower in moving areas of the packing jacket than in jammed areas, since the material of the packing jacket is in there the free spaces can recede and thus "evade" to high loads.

According to a further embodiment of the device, it is provided that the folding block has two oppositely arranged support surfaces which are arranged between the folding edges and the web and which have an angle of inclination of 5 ° or less with respect to a horizontal plane. A very small angle of inclination in the specified area ensures that the gable surfaces do not rest on the support surfaces during the pre-folding and are clamped there. Instead, a free space remains between the support surfaces and the pack jacket. This also enables particularly gentle folding. As already described above, this is due in particular to the fact that the material of the packing jacket can move and can recede into the free space. This reduces the risk of cracking. The angle of inclination can in particular be 0 °.

According to a further embodiment of the device, the folding strips are arranged on opposite sides of the folding block and are pivotably mounted. As a result of the arrangement on different sides of the folding block, the folding strips can reach the packaging sleeves arranged below the folding block from different sides and in particular fold two opposite sides of the packaging sleeve at the same time. A pivotable mounting of the folding strips represents a structurally simple solution for moving the folding strips between an open position - which allows the packaging sleeves to be transported - and a closed position - in which the packaging sleeves are pre-folded.

In a further embodiment of the device it is provided that the contact surfaces of the folding strips are flat. In particular, it can be provided that the contact surfaces of the folding strips are also flat in the area of the triangular surfaces - and thus over the entire width of the flat folded package jacket. A consistently flat design of the contact surfaces has the disadvantage that the packing jacket cannot be supported during the pre-folding in the area of the ears and thus less precise fold lines arise there. The advantage, however, lies in the gentler pre-folding. Because of the flat design, free spaces remain between the ears of the pack jacket and the contact surfaces of the folding strips during the pre-folding. The material of the packing jacket can therefore recede into the free space in the area of the ears during the pre-folding, which reduces the risk of cracking.

Another embodiment of the device provides that the back folder has a conical and / or spherical head. The head can, for example, have the shape of a sphere at its tip, which is followed by the shape of a conical jacket. Such a - convex - design of the head allows the material of the packing jacket to slide off the head particularly well. This allows a particularly gentle refolding and reduces the risk of the refolding device getting stuck on the pack sleeves or scratching the surface of the pack jackets, which are usually laboriously printed.

According to a further embodiment of the device, it is provided that each folding strip has at least one projection for folding the web surfaces. A particularly effective pre-folding of the web surfaces can be achieved by the projections. Such a pre-folding is aimed in particular in the area of the two "ends" of the web surfaces, since the material of the packing jacket has to be folded by 180 ° in these areas. The firm pressing together of the two ends of the web seam is also referred to as "pinching". Both folding strips preferably have two projections for folding the web surfaces, of which one projection is assigned to the first end of the web seam and the other projection is assigned to the second end of the web seam.

Finally, in a further embodiment, the device can be supplemented by a conveyor belt with cells for receiving the pack sleeves. A conveyor belt or a conveyor belt can transmit high tensile forces which allow a large number of pack sleeves to be attached to one another at constant intervals transport. The cells are used to hold the packing jackets. The packing jackets can be held in the cells by a form-fit connection as well as a force-fit connection. The conveyor belt is preferably arranged in a horizontal plane.

One embodiment not covered by the claimed invention relates to a method of prefolding package jackets. The method comprises the following steps: a) folding the gable surfaces inward, b) folding the ends of the web surface, and c) folding the triangular surfaces outward. The method is characterized in that the folding in step c) takes place without contact. A non-contact folding is understood to mean a folding in which there is no contact between the folding tools and the surfaces to be folded ("passive folding"). A "passive" folding of the triangular surfaces can be achieved, for example, in that the folding tools are in contact with the gable surfaces and thus "actively" fold the gable surfaces, as a result of which the triangular surfaces adjoining the gable surfaces are moved "passively". A "passive" folding is particularly gentle, since the folded surfaces do not need to be pinched or clamped.

An embodiment of the method not covered by the claimed invention provides for the addition of the following steps: d) folding the gable surfaces outward, and e) folding the triangular surfaces inward. The two additional steps concern the folding back, which serves the purpose of folding the pre-folded surfaces back a little in the opposite direction. On the one hand, this serves the purpose of being able to pull the folding block out of the pack jacket more easily and, on the other hand, makes it easier to fill the pack jacket with contents. The folding takes place in step d) preferably without contact. This can be achieved in that the backfolders are in contact with the triangular surfaces and thus "actively" fold the triangular surfaces inward, whereby the gable surfaces adjoining the triangular surfaces are moved "passively" (outward).

According to a further embodiment of the method not covered by the claimed invention, it is provided that the packaging jackets are moved by a conveyor belt with cells attached to them. As has already been described above in connection with the device, high tensile forces can be transmitted by a conveyor belt or a conveyor belt, which make it possible to transport a large number of pack casings at constant distances from one another. The cells are used to hold the packing jackets. The packing jackets can be held in the cells by a form-fit connection as well as a force-fit connection. The conveyor belt is preferably arranged in a horizontal plane.

According to a further embodiment of the method not covered by the claimed invention, it is finally provided that the pack jackets are moved intermittently, that is to say cyclically. An intermittent mode of operation has the advantage that the pack jackets stand still during the pre-folding and can thus be folded particularly precisely. The storage of the folding tools can also be designed to be simpler and more robust than in the case of a system in which the pack sleeves are transported further during the pre-folding.

The object described at the outset is also achieved by a system for pre-folding packaging sleeves. The system comprises: a device for prefolding package jackets according to any one of claims 1 to 11, and at least one pack jacket.

The invention finally relates to a pre-folded pack jacket, which is characterized in that the gable surfaces of the pack jacket are inclined inwardly in such a way that an angle of inclination in the range between 5 ° and 45 ° is formed between the gable surfaces and the front surface or the rear surface, and that the ears of the package jacket are inclined outwards in such a way that an angle of inclination in the range between 5 ° and 45 ° is formed between the ears and the side surfaces. The bottom surfaces of the package jacket are preferably sealed, that is to say closed.

Fig. 1A:

einen aus dem Stand der Technik bekannten Zuschnitt zum Falten eines Packungsmantels,

Fig. 1B:

einen aus dem Stand der Technik bekannten Packungsmantel, der aus dem in Fig. 1A gezeigten Zuschnitt gebildet ist, im flach gefalteten Zustand,

Fig. 1C:

den Packungsmantel aus Fig. 1B im aufgefalteten Zustand,

Fig. 1D:

den Packungsmantel aus Fig. 1C mit vorgefalteten Boden- und Giebelflächen,

Fig. 2A:

eine erfindungsgemäße Vorrichtung zur Vorfaltung von Packungsmänteln in einer Vorderansicht,

Fig. 2B:

die Vorrichtung aus Fig. 2A in einer Draufsicht entlang der Schnittebene IIB-IIB aus Fig. 2A,

Fig. 2C:

die Vorrichtung aus Fig. 2A in einer Seitenansicht entlang der Schnittebene IIC-IIC aus Fig. 2B,

Fig. 3A:

die Vorrichtung aus Fig. 2A in einer ersten Stellung im Querschnitt,

Fig. 3B:

die Vorrichtung aus Fig. 2A in einer zweiten Stellung im Querschnitt,

Fig. 3C:

die Vorrichtung aus Fig. 2A in einer dritten Stellung im Querschnitt,

Fig. 3D:

die Vorrichtung aus Fig. 2A in einer vierten Stellung im Querschnitt,

Fig. 4A:

die Vorrichtung aus Fig. 2A in einer ersten Stellung im Längsschnitt,

Fig. 4B:

die Vorrichtung aus Fig. 2A in einer zweiten Stellung im Längsschnitt,

Fig. 4C:

die Vorrichtung aus Fig. 2A in einer dritten Stellung im Längsschnitt,

Fig. 4D:

die Vorrichtung aus Fig. 2A in einer vierten Stellung im Längsschnitt, und

Fig. 5:

eine alternative Ausgestaltung einer erfindungsgemäßen Vorrichtung zur Vorfaltung von Packungsmänteln in einer Vorderansicht.

The invention is explained in more detail below with the aid of a drawing which merely shows a preferred exemplary embodiment. In the drawing show:

Fig. 1A:

a blank known from the prior art for folding a package jacket,

Fig. 1B:

a packing jacket known from the prior art, which is derived from the in Figure 1A shown blank is formed in the flat folded state,

Fig. 1C:

the packing jacket off Figure 1B in the unfolded state,

Fig. 1D:

the packing jacket off Figure 1C with pre-folded base and gable surfaces,

Fig. 2A:

a device according to the invention for pre-folding packaging sleeves in a front view,

Fig. 2B:

the device off Figure 2A in a plan view along the section plane IIB-IIB Figure 2A ,

Fig. 2C:

the device off Figure 2A in a side view along the section plane IIC-IIC Figure 2B ,

Fig. 3A:

the device off Figure 2A in a first position in cross section,

Fig. 3B:

the device off Figure 2A in a second position in cross section,

Fig. 3C:

the device off Figure 2A in a third position in cross section,

Fig. 3D:

the device off Figure 2A in a fourth position in cross section,

Fig. 4A:

the device off Figure 2A in a first position in longitudinal section,

Fig. 4B:

the device off Figure 2A in a second position in longitudinal section,

Fig. 4C:

the device off Figure 2A in a third position in longitudinal section,

Fig. 4D:

the device off Figure 2A in a fourth position in longitudinal section, and

Fig. 5:

an alternative embodiment of a device according to the invention for pre-folding package jackets in a front view.

In Figure 1A a blank 1 known from the prior art is shown, from which a package jacket can be formed. The blank 1 can comprise several layers of different materials, for example paper, cardboard, plastic or metal, in particular aluminum. The blank 1 has several fold lines 2 (or "crease lines"), which are intended to facilitate the folding of the blank 1 and divide the blank 1 into several areas. The blank 1 can be divided into a first side surface 3, a second side surface 4, a front surface 5, a rear surface 6, a sealing surface 7, two bottom surfaces 8, two gable surfaces 9 and twelve triangular surfaces 10. Web surfaces 11 adjoin the bottom surfaces 8, the gable surfaces 9 and the triangular surfaces 10. A pack jacket can be formed from the blank 1 by folding the blank 1 in such a way that the sealing surface 7 can be connected, in particular welded, to the front surface 5.

Figure 1B shows a package jacket 12 known from the prior art in the folded flat state. The ones already related to Figure 1A described areas of the packing jacket are in Figure 1B provided with corresponding reference numerals. The packing jacket 12 is made of the in Figure 1A shown blank 1 formed. For this purpose, the blank 1 was folded in such a way that the sealing surface 7 and the front surface 5 are arranged so as to overlap, so that the two surfaces are flat with one another can be welded. The result is a longitudinal seam 13. In Figure 1B the package jacket 12 is shown in a flat folded state. In this state, a side face 4 (in Figure 1B hidden) under the front surface 5 while the other side surface 3 on the rear surface 6 (in Figure 1B hidden). In the flat folded state, a plurality of packaging jackets 12 can be stacked in a particularly space-saving manner. Therefore, the package jackets 12 are often stacked at the place of manufacture and transported in stacks to the place of filling. Only there are the pack sleeves stacked and unfolded so that they can be filled with contents, for example with food.

In Figure 1C the packing jacket 12 is off Figure 1B shown in the unfolded state. Again, those are already related to Figure 1A or 1B Areas of the packing jacket 12 described are provided with corresponding reference numerals. The unfolded state is understood to mean a configuration in which an angle of approximately 90 ° is formed between the two adjacent surfaces 3, 4, 5, 6, so that the pack jacket 12 - depending on the shape of these surfaces - is square or rectangular Has cross section. Accordingly, the opposite side surfaces 3, 4 are arranged parallel to one another. The same applies to the front surface 5 and the rear surface 6.

the Figure 1D shows the packing jacket 12 from Figure 1C in the pre-folded state, that is to say in a state in which the fold lines 2 have been pre-folded both in the region of the bottom surfaces 8 and in the region of the gable surfaces 9. The bottom surfaces 8 and the gable surfaces 9 are folded inward during the pre-folding and later form the bottom or the gable of the packaging. The triangular surfaces 10, however, are (mostly passively) folded outwards during the pre-folding and form protruding areas made of excess material, which are also referred to as "ears" 14 and are applied to the packaging in a later manufacturing step - for example by gluing. As an alternative to this, the bottom surfaces 8 of the package jacket 12 can have been folded and sealed on a mandrel of a mandrel wheel before the gable surfaces 9 are prefolded in the manner described.

In Figure 2A a device 15 according to the invention for pre-folding package jackets is shown in a front view. Also shown is a conveyor belt 16 with cells 17 in which the packaging jackets 12 are first guided to the device 15 and are pre-folded there in the gable area. The transport direction T of the pack jackets 12 therefore runs parallel to the conveyor belt 16. The device 15 comprises two folding strips 18A, 18B for pre-folding the gable surfaces 9 of the pack jackets 12. For the sake of clarity, FIG Figure 2A only the rear folding strip 18A is shown. The folding strips 18A, 18B are arranged on opposite sides of the pack sleeves 12 and are mounted so that they can be moved vertically and pivoted. Each folding strip 18A, 18B has a flat contact surface 19 for folding the gable surfaces 9. In addition, each folding strip 18A, 18B has a back folder 20 for folding back the ears 14 of the package casings 12. The in Figure 2A The rear folder 20 shown and thus preferred has a head 21 which has a cone-shaped section and a spherical section. Each folding strip 18A, 18B also has at least one projection 22 for folding the web surfaces 11.

In the Figure 2A The device 15 shown comprises, in addition to the two folding strips 18A, 18B, also a folding block 23 which is arranged centrally above the pack sleeves 12 and is mounted so as to be linearly displaceable. The folding block 23 can be mounted displaceably in the vertical direction Y in particular. The folding block 23 has a web 24 which has a folding edge 25 on both sides in its lower region. The folding edges 25 serve to "break" the fold lines between the gable surfaces 9 and the front surface 5 or the rear surface 6.

Figure 2B shows the device 15 from Figure 2A in a plan view along the section plane IIB-IIB Figure 2A . The ones already related to Figure 2A described areas of the device 15 are in Figure 2B provided with corresponding reference numerals. The arrangement of the two folding strips 18A, 18B can be seen particularly clearly in the plan view. Each folding strip has a flat contact surface 19 and a back folder 20 on, wherein the rear folder 20 of the rear folding strip 18A is arranged diagonally opposite the rear folder 20 of the front folding strip 18B. In this way, one back folder 20 can fold back the left ear 14, while the other back folder 20 can fold back the right ear 14. In addition, the two folding strips 18A, 18B each have two projections 22 for folding the web surfaces 11. In the top view it can be seen that two projections 22 are assigned to one another and are arranged opposite one another, so that two projections 22 cooperate and can fold the web surface 11 at both "ends".

In Figure 2C the device is off Figure 2A in a side view along the section plane IIC-IIC Figure 2B shown. Again, those are already related to Figure 2A or Figure 2B Areas of the device 15 described are provided with corresponding reference numerals. In the side view it can be seen particularly clearly that the folding strips 18A, 18B and the folding block 23 in FIG Figure 2C assume a neutral, open position in which a free space is created between the two oppositely arranged folding strips 18A, 18B and the folding block 23, in which the unfolded package jackets 12 can be arranged. During the folding process, however, the folding strips 18A, 18B and the folding block 23 assume a different position, which will be discussed in more detail below.

Figure 3A shows the device 15 from Figure 2A in a first position in cross section. Also in Figure 3A are already related to Figures 2A to 2C Areas of the device 15 described are provided with corresponding reference numerals. In the first position, the two folding strips 18A, 18B assume a neutral position in which neither the folding strips 18A, 18B themselves nor the backfolders 20 attached to them are in contact with the package jacket 12. The folding block 23, on the other hand, has already been introduced into the package jacket 12 from above, so that it is in Figure 3A assumes a lowered position. The folding block 23 has been lowered so far that the folding edges 25 of the folding block 23 are arranged at the level of those fold lines 2 which separate the front surface 5 and the rear surface 6 from the gable surfaces 9. The folding block 23 has two support surfaces 26, which are on opposite sides of the web 24 are arranged. The support surfaces 26 preferably have an angle of inclination α of 5 ° or less, in particular of 0 °, with respect to a horizontal plane H.

In Figure 3B the device 15 is off Figure 2A shown in a second position in cross section. Also in Figure 3B are already related to Figures 2A to 3A Areas of the device 15 described are provided with corresponding reference numerals. In the second position, the folding block 23 is unchanged in a lowered position. The two folding strips 18A, 18B, however, were pivoted inward (shown schematically by arrows) so that the contact surfaces 19 of the folding strips 18A, 18B touch the gable surfaces 9 of the package jacket 12 and press inward. The (in Figure 3B Triangular surfaces 10 (not shown) passively - that is, without contact by the folding strips 18A, 18B - to the outside, whereby the ears 14 are formed. The folding block 23 preferably has a web 24 with a web width of less than 3 mm, in particular less than 2 mm, so that the gable surfaces 9 can be folded particularly far inward. Since the angle of inclination α in the in Figure 3B The folding block 23 shown and preferred in this respect is zero degrees, a free space 27 is created between the support surfaces 26 and the gable surfaces 9. It is therefore deliberately omitted to use the support surfaces 26 as a support for the gable surfaces 9 during the folding process in order to avoid damage to the pack jacket 12 to avoid.

Figure 3C shows the device 15 from Figure 2A in a third position in cross section. Also in Figure 3C are already related to Figures 2A to 3B Areas of the device 15 described are provided with corresponding reference numerals. Even in the third position, the folding block 23 is unchanged in a lowered position. The two folding strips 18A, 18B, on the other hand, have been pivoted outwards, as a result of which the rear folders 20 attached to them move inwards (shown schematically by arrows). This has the consequence that the heads 21 of the backfolders 20 touch the ears 14 of the pack jackets 12 and push them up again somewhat. In the process, the gable surfaces 9 move passively - that is, without being touched by the backfolders 20 or folding strips 18A, 18B - somewhat outward again.

In Figure 3D the device 15 is off Figure 2A shown in a fourth position in cross section. Also in Figure 3D are already related to Figures 2A to 3C Areas of the device 15 described are provided with corresponding reference numerals. In the fourth position, the two folding strips 18A, 18B were first pivoted back into the neutral position, which was already in connection with Figure 3A has been described. Subsequently, the folding block 23 was pulled back upwards out of the pack jacket 12 so that it was in Figure 3D occupies a raised position. The distance between the two gable surfaces 9 is smaller than the distance between the two folding edges 25 of the folding block 23 vertical position and then spring back into the inwardly inclined position. As a result of the folding back, the gable surfaces 9 are inclined inward in such a way that an angle of inclination β in the range between 5 ° and 45 ° is formed between the gable surfaces 9 and the front surface 5 or the rear surface 6.

Figure 4A shows the device 15 from Figure 2A in a first position in longitudinal section. Also in Figure 4A are already related to Figures 2A to 3D Areas of the device 15 described are provided with corresponding reference numerals. In the Figure 4A The position shown corresponds to that of Figure 3A known position, the view being rotated by 90 °. In the longitudinal section it can be clearly seen that the width of the folding block 23 is just as wide or wider than the width of the front surface 5 (and the rear surface 6, not shown). The purpose of this is that the triangular surfaces 10 can only move outward, but not inward, during the folding process. It can also be clearly seen in the longitudinal section that the length L _{F of} the folding edge 25 is shorter than the length L _{G of} the gable surface 9, preferably at least 5% shorter or at least 10% shorter. It is therefore deliberately omitted to continue the folding edge 25 into the corners of the pack jacket 12 in order to avoid damage in this area of the pack jacket 12.

In Figure 4B the device 15 is off Figure 2A shown in a second position in longitudinal section. Also in Figure 4B are already related to Figures 2A to 4A Areas of the device 15 described are provided with corresponding reference numerals. In the Figure 4B The position shown corresponds to that of Figure 3B known position, the view being rotated by 90 °. In the longitudinal section it can be clearly seen that an inward folding of the gable surfaces 9 results in an outward folding of the triangular surfaces 10, which results in protruding ears 14 on the two narrow sides of the package jacket 12. The position and the function of the projections 22 can also be clearly seen: they are intended to press the two "ends" of the web surface 11 together and thus pre-fold them. The contact surface 19 of the folding strip 18B is flat and has a length L _K which is longer than the length L _{G of} the gable surfaces 9 folded by it. In this way, it is achieved that the ears 14 have no contact with the contact surface 19 during the folding process and thus a particularly gentle folding is achieved.

Figure 4C shows the device 15 from Figure 2A in a third position in longitudinal section. Also in Figure 4C are already related to Figures 2A to 4B Areas of the device 15 described are provided with corresponding reference numerals. In the Figure 4C The position shown corresponds to that of Figure 3C known position, the view being rotated by 90 °. The contact between the head 21 of the rear folder 20 and the ears 14 of the packaging jackets 12, which are pushed back up somewhat by the rear folder 21, can be clearly seen. In the process, the gable surfaces 9 move passively - that is, without being touched by the backfolders 20 or folding strips 18A, 18B - somewhat outward again.

In Figure 4D the device is off Figure 2A shown in a fourth position in longitudinal section. Also in Figure 4D are already related to Figures 2A to 4C Areas of the device 15 described are provided with corresponding reference numerals. In the Figure 4D The position shown corresponds to that of Figure 3D known position, the view being rotated by 90 °. The folding block 23 takes in Figure 4D returns to the raised position after being pulled out of the pack jacket 12 has been. The gable surfaces 9 are folded slightly inwards while the triangular surfaces 10 are folded slightly outwards and form protruding ears 14. As a result of the folding back, the ears 14 are inclined outward in such a way that an inclination angle γ in the range between 5 ° and 45 ° is formed between the ears 14 and the side surfaces 3, 4.

Fig. 5 finally shows an alternative embodiment of a device 15 'according to the invention for pre-folding pack sleeves in a front view. As an alternative to the in Figures 2A to 4D The embodiment of the device 15 shown in FIG Fig. 5 device 15 'shown is provided that the device folds two packaging jackets 12 at the same time. This is achieved by lengthening the folding strips 18A, 18B and by correspondingly increasing the number of folding blocks 23 and the components provided on the folding strips 18A, 18B (back folders 20, projections 22). The cells 17 are connected to one another via a rigid bridge 28. The bridge 28 is driven via two conveyor belts 16. With a corresponding adaptation, devices are also possible in which three or more packaging sleeves can be folded at the same time.

List of reference symbols:

1:

Cutting

2:

Fold line

3, 4:

Side faces

5:

front face

6:

rear face

7:

Sealing surface

8th:

Floor area

9:

Gable surface

10:

Triangular face

11:

Bridge surface

12:

Packing coat

13:

Longitudinal seam

14:

ear

15:

Pre-folding device

16:

Conveyor belt

17:

cell

18A, 18B:

Folding bar

19:

Contact area

20:

Backfolders

21:

Head (of back folder 20)

22:

head Start

23:

Folding block

24:

Web (of the folding block 23)

25:

Folding edge (of folding block 23)

26:

Support surface (of the folding block 23)

27:

free space

28:

bridge

α:

Angle of inclination (of the support surfaces 26)

β:

Angle of inclination (of the gable surfaces 9)

γ:

Angle of inclination (of ears 14)

H:

Horizontal plane

LF:

Length (of the folding edge 25)

LG:

Length (of the gable surface 9)

LK:

Length (of the contact surface 19)

T:

Direction of transport (of the packaging sleeves 12)

X:

Longitudinal direction

Y:

Vertical direction

Z:

Transverse direction

Claims (10)

1. Apparatus (15) for pre-folding pack sleeves (12), comprising:

   - at least two folding strips (18A, 18B) for pre-folding the gable surfaces (9) and the triangular surfaces (10) of the pack sleeves (12),

   - at least one folding block (23) which can be introduced into the pack sleeve (12), and

   - at least one back folder (20) for folding back the triangular surfaces (10),

   - wherein the folding strips (18A, 18B) each have at least one contact surface (19) for pre-folding the gable surfaces (9), and

   - wherein the folding strips (18A, 18B) are arranged on opposing sides of the folding block (23) and are mounted so as to be pivotable,

   characterised in that
   the back folder (20) is fastened to one of the folding strips (18A, 18B).
2. Apparatus according to claim 1, characterised in that the folding block (23) is mounted so as to be linearly displaceable.
3. Apparatus according to claim 1 or 2, characterised in that the folding block (23) has a web (24) with a web width of less than 3 mm, in particular of less than 2 mm.
4. Apparatus according to any one of claims 1 to 3, characterised in that the folding block (23) has two folding edges (25) arranged opposite one another for folding the gable surfaces (9).
5. Apparatus according to claim 4, characterised in that the length (L_F) of the folding edges (25) is at least 5% shorter than the length (L_G) of the gable surfaces (9) to be folded.
6. Apparatus according to any one of claims 1 to 5, characterised in that the folding block (23) has two support surfaces (26) arranged opposite one another which are arranged between the folding edges (25) and the web (24) and which have an angle of inclination (α) of 5° or less with respect to a horizontal plane.
7. Apparatus according to any one of claims 1 to 6, characterised in that the contact surfaces (19) of the folding strips (18A, 18B) are designed flat.
8. Apparatus according to any one of claims 1 to 7, characterised in that the back folder (20) has a conical and/or spherical head (21).
9. Apparatus according to any one of claims 1 to 8, characterised by a transport belt (16) with cells (17) for receiving the pack sleeves (12).
10. System for pre-folding pack sleeves (12), comprising:

    - an apparatus (15) for pre-folding pack sleeves (12) according to any one of claims 1 to 9, and

    - at least one pack sleeve (12).

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