EP0804336A1

EP0804336A1 - Device for processing a blank conveyed along a transport path at a predetermined transport speed

Info

Publication number: EP0804336A1
Application number: EP95937053A
Authority: EP
Inventors: Karl Heinz KRÜGER; Manfred Pszak
Original assignee: Alfred Klett KG
Current assignee: Alfred Klett KG
Priority date: 1994-11-06
Filing date: 1995-11-06
Publication date: 1997-11-05
Anticipated expiration: 2015-11-06
Also published as: JPH10508548A; ES2121427T3; EP0804336B1; AU3927595A; WO1996014204A1; ATE168622T1; DE59502935D1; US5997459A; DE4439198A1; CA2204495A1; DK0804336T3

Abstract

PCT No. PCT/EP95/04368 Sec. 371 Date May 2, 1997 Sec. 102(e) Date May 2, 1997 PCT Filed Nov. 6, 1995 PCT Pub. No. WO96/14204 PCT Pub. Date May 17, 1996The present invention relates to a folding machine for folding the side flaps flanking the middle section of a foldable cardboard blank. For this purpose in the frontal area of the folding machine auxiliary folding devices are arranged. In addition turning belts for the inward tilting of the side flaps can be arranged, which are provided with projections insuring that the side flaps are swung parallelly to their folding grooves.

Description

DESCRIPTION

Device for processing a blank conveyed along a conveying path with a predetermined conveying speed

The invention relates to a device for processing a blank that is conveyed along a conveying path at a predetermined conveying speed according to the preamble of claim 1.

The invention relates in a special embodiment to a folding machine for producing a folding container from a blank conveyed along a conveying path at a predetermined speed, the middle part of which has laterally arranged hinge-like folding grooves on which side parts sit, which are raised by means of turning devices in the course of the conveying path from an initially spread position along the fold grooves are increasingly pivoted inwards towards the longitudinal center of the blank and finally folded together from above and connected to one another.

Devices of this type, in particular folding machines, are known (see, for example, brochure "In-Line Machine 2000", Velcro corrugated cardboard machines, Remscheid).

In the context of the present application, the terms “device for processing a blank conveyed along a conveying path with a predetermined conveying speed” and “folding machine” are always used synonymously, since all the features underlying the invention match both in such a device and in such a folding machine. Although the present invention generally starts from a folding machine for producing folding containers from flat material blanks, the present invention relates in a preferred embodiment to folding machines for producing folding containers made of folding cardboard. In particular, corrugated cardboard blanks are to be used as starting materials.

A limitation of the invention to folding cardboard blanks only from corrugated cardboard is not intended to be hereby, however. Therefore, in the following, unless expressly stated otherwise, the materials corrugated cardboard, folding cardboard are treated synonymously, in particular the term folding cardboard also includes the general term folding container, provided that the folding container is produced on a folding machine in the sense of this invention.

Such folding cardboard blanks exist for. B. from corrugated cardboard. For this purpose, a corrugated cardboard sheet is folded parallel to the shaft for each folding carton where the side flaps are to be hinged on the middle section.

It should be expressly stated that the present invention is in no way limited to folding machines for producing folding containers which are closed on all sides. Rather, folding machines are also suitable for the production of envelope-like folding containers. These are e.g. B. protective coverings without a lid and / or without a bottom. With protective coverings of this type there is the problem that the object picked up must fit as precisely as possible into the interior of the protective cover. Eliminating the bottom and / or lid means that there is otherwise a risk of slipping out unintentionally. A practically relevant case occurs e.g. B. in the coating of motor vehicle headlight reflectors. These reflectors are usually placed in corrugated cardboard envelopes. The inside dimension of the envelope is so narrow that the reflector is held in it. Another application example is, as I said, folding cardboard blanks that correspond to a developed rectangular box with bottom and lid. Such boxes are usually processed further on packaging machines. For this reason, the quality of the product leaving the folding machine is of particular relevance.

Such a folding cardboard blank can also be provided with the necessary slots or recesses. For this purpose, the corrugated cardboard sheet is parallel to the area in the fold grooves

Slotted or recessed shaft. The slot width is approximately z. B. 1 cm. The slot depth corresponds to the folding length of

Bottom or lid. As a result, the bottom and lid of the folding box are freely movable on the rest of the box. Three slots can usually be left out exactly. A fourth slot is created in the area of the two side flaps which are folded together and are to be connected to one another. One of the two side flaps also has a so-called binding margin or glue margin. It is a tab on which a fold groove is also provided.

The fold grooves in any case form the hinges between the side flaps and the middle part. Usually four fold grooves are provided for cuboid boxes, in each case one fold groove is provided on both sides of the middle part, and one fold groove within the middle part and one fold groove in the region of the two folded side flaps. In such folding machines, the pre-cut blanks, if any, are now conveyed, while at the same time either the fold grooves are incorporated into the blank or, in the case of fold grooves which have already been prepared, the side flaps which are still spread out are gripped and folded in the course of the conveying path. Folding takes place in a manner known per se by means of so-called reversing belts, which first grip the side flaps from below. The turning belts run from one level below to one level above the middle part. The axes of the reversing belts are interlaced in such a way that the belt surface facing the folding cardboard blank turns by a total of 180 degrees along the conveying path. Usually, two such reversing belts are therefore arranged one behind the other on each side of the middle part, of which each reversing belt is only folded by 90 degrees.

The problem on which the invention is based is to keep the inside dimensions of all the folding cartons of a lot produced on a machine within the narrowest possible tolerances.

In the event that the folding boxes are rectangular boxes with slot-like recesses at the ends of the folding grooves, this results in the subordinate task of further developing the known folding machine so that all slot widths of a folding box can be produced with the same dimensions.

The object is achieved in the known folding machine in that, at least in the front region of the conveying path, there is provided a folding device which engages above and below the blank in such a way that a folding edge running in the longitudinal direction of the folding groove lies linearly in the folding groove on the top of the blank that a support zone corresponding to the folded edge is formed on the underside of the blank, and the folding device is driven synchronously with the conveying speed.

The invention is based on two embodiments, with which different approaches to solving the problem are taken with matching device features. The first embodiment is based on line-shaped clamping of already existing folding grooves with simultaneous inward pivoting movement of the side parts (= folding station). The second embodiment is based on the production of fold grooves which are not yet present by linear clamping of the blank (= crease station).

The advantage of the invention is that, irrespective of the width of the folding groove, a folding edge between the side flap and the middle part that is precisely positioned in the millimeter range and runs with the speed of the blank is offered for each side flap. With regard to the cutting, the processing takes place statically according to this invention. This not only eliminates the harmful dynamic and difficult to predict influences, but also produces excellent qualities at high speed.

The distance between the two folded edges does not change over the conveying path. In the first embodiment, in addition to the line-shaped clamping of the blank, each side flap is folded inwards. The folded edges offer the side flaps swiveled in from the outside, for example by means of the reversing belts, to support the folded area from the inside, on which the swivel movement is forced with millimeter precision. The invention makes use of the fact that corrugated cardboard blanks of this type, based on the basic dimensions of the blank, are always folded at matching locations. However, these fold grooves have a certain width, e.g. B. of about 1 cm. The fold groove width is understood to mean the width in the blank that is usually produced by so-called pre-squeeze rolls. Here, the Zu cuts in the gap between opposite rolls. These rolls are very close to each other, which is less than the cutting thickness. The blank is thus squeezed to be prepared for the subsequent installation of the fold groove. This creates a certain fold area, in which the actual hinge axis will then lie.

Consequently, due to the internal structure of such corrugated boxes, the geometrically precise position of the actual hinge axis for the pivoting movement was more or less left to chance.

Without the measures according to this invention, the actual hinge axis is only somewhere within the width of the groove.

The folding device as a separate creasing station eliminates this disadvantage by precise, linear clamping of the blank over the entire blank length when creasing.

The folding device together with a turning device (= folding station) eliminates this disadvantage by precise linear clamping of the blank during simultaneous inward pivoting movement of the side flaps.

All embodiments of the invention include the linear clamping of the blank by the folding device. The clamping lines can also be realized in that the folding edge and the corresponding support zone act on the blank in the manner of a pair of scissors or a punch.

In practical observations, one could see that, despite geometrically identical cardboard cuts, fold grooves made in cardboard blanks never led to exactly matching internal dimensions. The material cross section plays in Area of the rebate groove plays a significant role, since this is where the stiffening effect of the shaft comes into play. The course of the shaft with different fold grooves is always purely random, so that uniform conditions for fold grooves were only created with this invention.

It was found that corrugated cardboard, depending on the shape of the corrugation in the groove, had an unintended and unpredictable shift in the actual folding zone. The fold zone always occurred where the folded cardboard blank happened to have the lowest bending stiffness.

Conventional creasing devices (e.g. rollers running against each other) do not prevent the blank from relaxing again immediately after creasing as soon as it is no longer subjected to the constraints of the rollers. The punctiform clamping between the rollers ensures local deformation of the blank under high pressure, but cannot be maintained down the conveyor path and is not effective up the conveyor path.

The invention differs significantly from this in that the linear clamping of the blank takes place statically on the blank, specifically over the entire blank length. The scoring is thus carried out by a static displacement over the entire cut length. The displacement can therefore only take place laterally and not, as in the case of opposing rollers, also in or against the conveying direction.

Especially with low cardboard strengths, this problem arises.

This shifting of the actual folding zone within each fold groove resulted in different folding results with pre-slit cuts with different slit widths in the area of the side flaps placed one on top of the other. There inaccuracies in the geometric position of the actual folding act ne is particularly severe within the rebate grooves. In the worst case, the inaccuracies of the other places can add up at this point. In this context, attempts have been made to attach so-called folding swords in the rear area of the conveyor path, i.e. where the side flaps are folded between 90 and 180 degrees. These are sword-like sheet metal strips located just above the middle part of the folded cardboard blank, the edges of which should point outwards in the fold grooves. The ends upstream are fixed in place. However, the ends lying down the conveyor path project freely. The free length can be up to two meters and more. It is therefore understandable if a cardboard blank that has already been folded too tightly is able to compress the freely projecting heavy ends. On the other hand, errors in carton blanks that are too far pre-folded can also no longer be remedied, since the folding swords then no longer have any contact with the folding zones. A correction of any incorrect pre-folding, too wide or too narrow, is therefore not possible in this way. The effect of the precise carton guidance intended by means of these folding swords was therefore subject to narrow limits. On the other hand, the free ends of the folding swords can also not be clamped in place, since in the area of the free ends the side flaps must lie closed on the middle part in order to be able to glue them there. The invention deviates completely from this known teaching. The invention has recognized that a considerably increased accuracy can be achieved solely by the precise application of the fold groove or by precise initiation of the folding process with a folding zone defined to the millimeter.

This is only possible on the front part of the funding path. The side flaps are initially spread out in the front part of the conveyor path.

If it is a creasing station, the folded creases are inserted into the blank when they are spread out.

If it is the other embodiment (= folding station), the side flaps are pivoted inward from the extended position at least 50 degrees during the clamping of the blank.

The geometrically exact processing of the blank (creasing or pre-folding) in the front region of the conveying path is essential to the invention and does not require any subsequent correction.

Here, the provided folding device enables the exact positioning of the later folding zone in the fold groove before the start of the folding process, regardless of the respective cross-sectional structure of the carton blank in the area of the fold groove. The folding device engages directly in the fold groove. The shaft lying between the cover layers of the corrugated cardboard is flattened out so that one can speak of a cross-sectional structure that is uniform for all folding grooves. The folding edges of the folding device also extend along the conveying path to such an extent that the folding zones can no longer move on the remaining conveying path.

Aue dieeem reason in the front area of the conveyor path, the side flaps are guided exactly along the intended folding edges, and in the rear area of the conveyor paths there is no longer any change.

It is sufficient to attach the folding device only in the front area of the conveyor path. In the case of a creasing station, this means the longitudinal region of the conveying path on which the side flaps lie spread out. In the other embodiment of the invention (= folding station), this means the longitudinal area on which the side flaps are folded down from the extended position to at least an approximately right angle. The particular advantage results from the following combination:

On the one hand, the side flaps are still widely spread on the front area of the conveyor path. On the other hand, it is only possible in the front area of the conveying path that the folding device is also on the end, ie. H. conveyor path waste, to be clamped so that the exact position of the folding edge in the folding groove is identical for all folding cartons produced on a folding machine.

This prevents the folding groove (^ hinge axis) from running too tightly or too tightly pre-folded carton cuts.

It is important that the two parallel folding edges, which engage in the fold grooves, have a constant distance from one another and span a plane that is parallel to the plane of movement of the conveyed middle parts. This forces the side panels to fold exactly at right angles.

As a result, a possibly narrow area of the rebate groove becomes a hinge between the middle part and the side flap. However, this means that the position of the actual folding zone is geometrically exactly fixed, which additionally increases the accuracy of the calibrated slot width of the last slot in the case of slotted cardboard cuts. It is also essential that there is no relative movement in the conveying direction in the contact area between the folded edge, the support zone and the folded cardboard blank. This avoids wear and also enables the contact pressure between the folding device and the cardboard blank to be increased. Hot running is also not to be feared.

The folding device according to the invention is driven by a synchronous drive at a conveying speed such that the processing on the carton takes place at the conveying speed of the carton. It is advantageous to avoid any slippage, so that static conditions can actually be assumed at the cut. The folded edges are preferably realized by circumferential end loops, the chain links of which point in the fold grooves with puddle-like or eteg-like extensions.

Such end loops are driven synchronously at the conveying speed.

It is an advantage if the sheet-like extensions with their outer sides facing the side flaps form an angle of no more than 90 degrees, preferably no more than 70 degrees, with respect to the plane of the middle parts. There are also conceivable designs in which the folded edges are guided as far as possible along the conveying path, the side parts have approximately the space between the side flap and the middle part, which is increasingly smaller due to the side flap swung inwards, and is optimally used and, on the other hand, a high proportion of the pressing force exerted on the folding carton cut brought. For a creasing station with a protruding projection, on the other hand, it is important to press the folded edge and the corresponding contact zone as gently as possible against the cut to convert the greatest possible proportion of the compressive force into the desired deformation of the blank in the area of the fold groove.

The features of claims 6-9 provide a further improvement in production accuracy and serve, in particular, to pivot the side parts of the blanks inward only by those pivoting forces which are not only the same size and rectified between the front contact point and the rear contact point between the side part and the reversing belt attack essentially with respect to the fold grooves on the side parts such that the side edge of the side part to be pivoted inward is held parallel to the fold groove while the pivoting movement is impressed on the side part. This results in particular in the advantage that the side parts pivoted inwards in this way can also be pivoted precisely about the pivot axis in the fold groove when the blank has already completely or partially left the area of the folding device. Thus, regardless of the engagement ratio between the folding device and the cut, one and the same swivel axis in the rebate groove is always maintained, the swivel axes which are decisive for the two side flaps remaining exactly parallel. The folding container is therefore folded exactly in a cuboid shape.

The invention is explained in more detail below with reference to exemplary embodiments.

Show it

1 shows a folding machine in a three-dimensional view, FIG. 2 shows the front area of a folding machine according to FIG. 1 in

View from above,

Figure 3 top view in the longitudinal direction of a folding machine according to

Figure 1,

FIG. 4 shows a side view of a folding machine according to FIG. 1, FIG. 5 shows a side view of a folding machine according to FIG. 1, FIG. 6 is a detailed view of a folding device with an endlessly rotating link chain (upright running plane),

FIG. 7 is a detailed view of a folding device with an endless chain of paces (horizontal running plane),

Figure 8 is a schematic view of a folding machine with creasing station.

Figure 9 special version of the folding device

for creasing station according to FIG. 8

10 a - c

Interaction between the reversing belts and the side parts of the blanks a) most common case

b) possible borderline case

c) theoretically conceivable case

Unless otherwise stated below, the following description always applies to all figures.

The figures show a folding machine 1 for producing a folding container. In principle, such a folding machine consists of a central conveyor belt 2 which rotates endlessly at conveyor speed 3. The outwardly facing belt surface of the conveyor belts 2 offers a support surface for a folding carton cut 5. This folding carton cut lies on the central conveyor belt 2 and is carried along by feet 4 connected to the conveyor belt in the conveying direction 3. Such a folding carton cut has a central part 6 with which it rests on the central conveyor belt 2. Both sides of the middle parts and a fold grooves 7 arranged ecitically. The fold grooves are identified here with double dashes running and interrupted in the longitudinal direction. The fold grooves 7 lie parallel to the conveying direction 3 and represent hinge-like connections between the middle part 6 and the respectively attached side part 8. The side parts 8 can be pivoted inwards with respect to the longitudinal center 10 of the blank 5 along these hinge-like folding grooves. So-called reversing belts 9, which are essentially parallel to the central conveyor belt 2, are used for this purpose. These are endless, circumferential flat belts that rise over the entire conveyor path from a level below the central conveyor belt 2 to a level above the central conveyor belt 2, converge slightly towards the central conveyor belt 2 and, at the same time, converge with their belt side facing upwards at the beginning at the end of the conveyor downwards, ie point towards the central conveyor belt 2. A side part 8 lies against each of these belt outer sides. The side part 8 must follow the entanglement of the turning belt and is thereby lifted out of the initially spread position, increasingly pivoted inward along the fold grooves to the longitudinal center of the blank and finally folded from above with the opposite side part 8 and connected to it.

In this way, in the case of such a folding machine, an initially unwound container blank becomes an annularly closed folding container with at least two fold grooves parallel to one another. It is now conceivable that the fold grooves 7 have a certain transverse extent, according to. Fig. 9 also called fold groove ready B.

This transverse extent can be in the range of 1 cm, for example. However, this means that the actual folding zone can lie anywhere within the folding groove 7.

The actual position of the folding zone is thus purely coincidental, unless additional measures are taken to initiate the folding process at a predetermined point (see FIG. 1) or if the folding grooves are not accurate to the millimeter Cut and placed there a priori (see Fig. 8).

For this purpose, it is provided according to the invention that a folding device is arranged in the front region 11 of the entire conveying path. This folding device 12 consists of a folding edge 13 lying above the blank 5 and a support zone 14 below the blank corresponding to the folding edge. The folding edge 13 arranged above the blank lies linearly on the blank 6 in the longitudinal direction of the folding groove 7. The line lies within the predetermined width of the fold groove 7. In this weakened area of the blank, a limiting edge is consequently provided according to the embodiment in FIG. 1, on which the side part 8 is pivoted inwards with millimeter precision, while it is simultaneously conveyed forward by the central conveyor belt 2.

For this purpose, the blank 6 is pressed against the corresponding contact zone 14 by the linear folding edge 7 with a predetermined force. The blank 5 is consequently clamped linearly on both sides of the central part 6 by the folding device 12 provided there at a predetermined position within the fold grooves 7. The spacing of the clamping zones is fixed by the arrangement of the folding devices 12 on the machine frame, so that identical internal dimensions can be expected for the entire lot of the folding containers produced on this folding machine. Furthermore, it is essential for both embodiments that the folding device 12 is driven synchronously with the conveying speed 3. A drive 15 for the folding device 12 is used for this purpose. The drive 15 here consists of the central machine motor 16. This machine motor usually drives all units of one such a machine. These drive means are not shown for reasons of clarity. However, it is important that all drive trains are coupled so that they are slip-free via mechanical connections in order to achieve a synchronous movement of all parts.

In the present case, in addition to the other machine parts, not shown, the motor 16 drives the sprockets 18, 19 of the same diameter in each case via a common chain 17, one of which (18) drives the folding edge 13 and the other one (19) Drive of the corresponding support zone 14 is used. The rotary movement of the drive 15 is transmitted to the opposite folding device 12 via a continuous drive axis 20. The movement of the corresponding support zone 14 is also synchronously coupled to the movement of the folding edge 13 on this side via an additional connecting chain 17.

This also applies to the execution according to. Fig. 8 with a separate creasing station.

For reasons of better clarity, the front reversing belt running on the right side of the blank is not shown in the illustration according to FIG. 1. From the entanglement of the turning belt 9 shown on the left-hand side, however, it can be seen that the turning belt outside is pivoted clockwise by 90 degrees from the initially horizontal direction inwards into the vertical direction. Accordingly, the front region of the conveying path 11, which is essential for this invention, is where the side part 8 has been pivoted inwards at least to the extent that the angle between the side part 8 and the middle part 6, at least essentially in a spread position (= 180 degrees), whose apex in the groove 7 is at most 120 degrees. It is not necessary for the folding devices 12 to engage the blank immediately at the start of the pivoting process. However, it is essential in any case that the swivel angle, calculated from the spread position of the blank, is in each case at least 60 degrees. It is assumed that with such a swivel angle, the folding zone within the groove 7 is already so precisely defined that an unintentional shift of the folding zone specified to the millimeter (= hinge axis) can no longer take place.

However, since mechanical parameters such as line width, pinching force, cardboard strength also play a role, and in particular the cut in the area of the fold groove must not be destroyed, these influencing factors must also be taken into account when defining the exact angular range. In any case, under normal conditions, an inward swivel angle of 60 degrees could already ensure the desired accuracy of the interior dimensions. In addition, it should be expressly stated that the fold edge should act linearly in the fold groove, but that this invention is in no way meant to be limited to uninterrupted linear contact zones between the fold edge and fold groove. It is essential that the linear course of the folded edge takes place at least with such longitudinal dimensions that the intended folding zone is not inadvertently displaced.

In addition, Figure 2 shows that the folded edge is formed by a continuously rotating chain. The chain strand forming the folded edge 13 is acted upon by a chain pressing device 21 from the opposite side of the strand. This chain pressing device 21 has sliding pieces 22 which lie along the folding edge 13 and which are seated on associated holders 23. A plurality of such holders 23 with sliders 22 is arranged on a common carrier 24. A pressure zone lying along the chain line is hereby realized in order to press the folded edge 13 into the fold groove 7 with a predetermined force. Each carrier 24 can be adjusted transversely to the conveying direction 3 by means of a holder 26 in the sense of a change in distance from the respective opposite carrier 24. The folding device 12 is thus adapted to different blank dimensions, it being particularly important to ensure that the position of the folded edges 13 is parallel to one another and, if possible, in a common plane. The common plane lies parallel to the plane of the blank 5.

In order to achieve the most precise possible folding, it is further proposed that the folding edges be placed exactly in the longitudinal centers 28 of the folding grooves 7. Using the proposed measures, the lowest section modulus should be expected there when the side flaps pivot.

As can also be seen from FIG. 2, the corresponding support zones 14 have a certain width 27, so that an edge strip still remains on both sides of the folded edges 13. As a result, it is sufficient to leave the position of the corresponding support zone 14, namely the support belt, unchanged when the distance between the supports 24 changes. For this development of the invention, the entire width 27 of the flat belt comes into consideration as the corresponding support zone 14.

FIG. 3 further shows that the folded edge can be formed by one of the belt edges of a circumferential folding belt 30. It is a flat belt. The axis 44 of the belt deflection roller 45 is slightly inclined with respect to the normal plane to the plane of the blank 5. It is preferably a so-called tracking toothed belt which can absorb lateral forces to a certain extent without shifting from its running plane. The belt track provided on such belts engages in a manner known per se in corresponding annular groove-shaped recesses in the deflection rollers 45. In this way, one can achieve a certain contact pressure between the folding belt edge 30 and the groove 7. As a result of the slight inclination of the belt axis 44, the belt drum running counter to the conveying direction can run past the blank with the free belt edge 31 without contact. Otherwise, this representation corresponds to the representation according to FIGS. 1 and 2. With regard to the features not expressly mentioned, reference is therefore made to the previous description. In addition, FIGS. 4 and 5 show a further development in which guide devices 32 are provided between the end-side Ural rollers 46, 47 of the belt section forming the support zone on the underside 48, with which said belt section is pressed against the underside of the blank 5.

In the case of Figure 4, the guide device consists of a guide rail 33 which is supported on elastic brackets 34. These elastic mounts consist on the one hand of a stationary receptacle 35 and of a rail counterpart 36 which can be moved longitudinally displaceably in this receptacle. The counterpart is elastically mounted in relation to the stationary receptacle with spring 37 and presses with a predetermined force against the underside of the belt zone forming the support zone 14 while at the same time the folded edge 13 is held in the opposite direction. In this way, a predetermined pressing force is created along the groove 7 and constant over the length of the front region of the conveying path.

However, guide rollers 38, which are arranged along the underside of the belt strand forming the support zone 14 and which press elastically against this underside in the same way, are particularly suitable for higher speeds. Through these measures, additional friction is avoided, wear is reduced, and nevertheless an essentially constant contact force is ensured in the area of the fold groove. Furthermore, FIGS. 6 and 7 show that the folded edges 13 are formed by cross plates of an endless chain 39 rotating at the conveying speed. This endless chain 39 lies in a recess corresponding to the outer chain contour of a chain guide rail 40 in each case. This chain guide rail 40 is a commercially available component and sits on a common carrier 49, which in turn is fastened to the machine frame.

A chain wheel 50 is arranged at each end of the chain guide rails 14, one of which is rotated via the motor 16. The chain guide rail extends along the front area of the conveyor path. The recess in the chain guide rail is closely matched to the outer contour of the chain links. Consequently, the cross brackets 41 exactly follow the linear course of the recesses along the front region of the conveyor path. In this way, an essentially constant contact pressure between the folded edge 13 and the fold groove 7 or the corresponding contact zone 14 can be achieved. In addition to this, the guide device / chain guide rail can be acted upon by hydraulic cylinders. This offers the advantage of a contact force between the folded edge and the corresponding support zone that is independent of the caliber thickness or carton quality.

In the case of FIG. 6, the axes 51 of the chain wheels are arranged essentially parallel to the plane 42 of the blank 5. However, the axes 51 can be slightly inclined to the longitudinal center 10 of the blank 5 in order to avoid an early collision with the inwardly pivoted side parts 8. In any case, however, the axes are also arranged perpendicular to the conveying direction 3 in order to avoid relative movements between the cross plates 41 and the blank 5. With such an arrangement of the axis 51, the transverse link plates 41 point radially outwards, based on the axis 51. The embodiment according to FIG. 7 differs from this in that the axes 51 of the end sprockets 50 are essentially perpendicular to the plane 42 of the blank 5, the cross plates 41 now being angled so far that they are essentially parallel to the axes 51, that is to say between exactly parallel and positively inclined to the outside (FIG. 7), and point to the blank 5.

Figure 8 shows that the folding device according to the invention is also suitable as a separate station 55 for the production of fold grooves. Such use should be expressly included.

In the case of such a folding machine, a feed station 52, possibly an inking station 53, and a slitting station 54 are arranged one behind the other in the running direction 3. A creasing station 55 can now be provided, by means of which the incoming flat blanks are creased in the conveying direction. Bending devices such as those described above are used for this purpose. In this case, however, the side parts are not pivoted inward, so that the pre-grooved flat blanks are required to form a stack 56.

Embodiments are particularly considered in which the support zone 14 forms a longitudinal groove 58 which is flanked by one or two raised longitudinal regions 59. The folded edge forms, with a longitudinal web 60, the counterpart to the longitudinal groove, which essentially lies opposite the longitudinal groove 58 (see FIG. 9). The longitudinal web 60 can be pressed into the longitudinal groove 58 with a precise fit, so that the blank is clamped in a line and at the same time is at least temporarily statically grooved.

It can be seen that the distance between the folded edge 13 and the corresponding support zone 14 is less than the thickness D of the material blank. In this area, the

Cut flat by constricting the side areas. The constriction takes place continuously, so that ultimately the width B of the fold groove cannot be precisely set. However, the width B essentially comprises the constricted area.

A downstream folding station 57, as described above, can also be provided.

In addition to this, FIGS. 10a to c show a development of the invention which is suitable for folding the side parts 8 of the blanks 6 inwards in such a way that a cuboid-shaped folding carton is produced in practice.

The section of a conveyor belt 2 that is moving in the direction of travel 3 is initially shown. The middle part 6 of the blank rests on the conveyor belt 2 and is carried along on a rear edge by the driver 4 in the conveying direction.

The fold grooves 7 have already been introduced with the folding device. However, the folding device can also lie in the fold grooves 7. Because of the continuously moving central conveyor belt 2, the existing folding grooves 7 therefore sweep a so-called travel area along the conveyor path, which forms a geometric travel line. The central part 6 is moved within these driving lines, the side parts 8 now having to be folded in. The reversing belts 9 are used for this purpose, of which the longitudinal section is shown that is currently interacting with the side parts 8. The turning belts 9 rise with respect to the linear travel areas of the folding grooves 7 from below to above and converge from outside to inside, as is also shown in FIG. 1.

The turn belts are therefore in principle not exactly parallel to the side parts 8. However, the belt outer sides 62 run in each case convergent to the pre-emphasized in the drawing derkanten of the side parts 8 and lie there. Depending on the respective belt geometry, there are front contact points 61 which, according to FIG. 10a, can lie on the belt edge 64 facing the folding groove 7, can extend over the entire belt width according to Figure 10b or are arranged according to 10c in the region of the belt edge 63 facing away from the folding groove 7 are.

The difference in FIGS. 10 a - c therefore essentially consists in showing the different possible contact points 61 between the outside of the belt 62 and the front region of the side parts, which is emphasized here in the drawing. As a result of the fact that the axes of the belt deflection rollers (see FIG. 1) are crossed at a certain angle to one another, the rear regions of the side parts 8 therefore have a predetermined geometric position relative to the outer sides of the reversing belts 9. In any case, this must be assumed that in the rear area of the side parts 8 between the belt outside 62 and the outside of the side part 8, direct contact is initially ruled out.

One of the belt edges, here 64, is closer to the outside of the side flap 8 than the other of the belt edges (here 63).

In order to obtain a geometrically one-way contact on the reversing belt 9 for the side flap 8, an elevation 65 must be provided on one of the two belt edges 63, 64.

In a preferred embodiment, this increase should lie on the further spaced belt edge 63 in order to obtain a favorable spacing for pivoting the side flap 8 with respect to the fold groove 7 forming the hinge axis.

The peculiarity is that the elevation 65 rises so far above the belt outside 62 that the scit part 8 is also guided there with its rear region. In addition to the front contact parts 61 here also a rear contact point 66, which preferably engages with a larger lever arm with respect to the folding groove 7 on the side part 8. In addition to the requirement that the side part 8 should also abut the rear contact point 66, it must also be ensured that the inward-pivoting side edge 67 is held practically exactly parallel to the folding groove 7 while the blank is driven in the conveying direction and while the side part 8 is doing so is pivoted inwards. For this purpose, FIGS. 10 a - c each show a geometric line A, which represents the pivot axis in the rebate groove 7, and a line C, which coincides with the side edge 87 to be pivoted inwards. Lines A and C are shown exactly parallel here. As a result of the height dimensioning of the elevation 65, the side part 8 is supported such that the line c lies exactly parallel to the line A. The continuously inward swiveling reversing belt 9 ensures practically precise compliance with this parallelism as long as and while the side part 8 is swung inward from the spread position to complete the cutting (see FIG. 1).

It should also be taken into account here that the front contact point 61 and the rear contact point 66 can in principle only rest against the side part in a punctiform manner in order to prevent the point of attack between the reversing belt and side part from moving sideways during the inward pivoting movement.

If one additionally wants to prevent bending of the side part 8, it is additionally proposed to connect the front contact point 61 and the rear contact point 66 by means of a common envelope 68, which should also lie linearly on the side part 8. This can be achieved, for example, by arranging continuously decreasing elevations 65 along the envelope 68 starting from the rear contact point 66 to the front contact point 61, the contact points of which with the side parts 8 in each case on the envelope 68 should lie. Here too, only punctiform contact should be preferred, so that ideally the envelope 68 is only a line. The envelope 68 should particularly preferably run diagonally from the rear contact point 66 via the turning belt 9 to the front contact point 61. However, this is not a requirement. It is essential to measure the height of the elevation 65 so that the side edge 67 of the side part 8 is exactly parallel to the fold groove 7 when the side part 8 is supported on the elevation 66.

Furthermore, it is also not important for the length of the side part 8 to exactly match the length of the envelope 68. Rather, the envelope 68 can also be longer than the side part 8. In this way, such a reversing belt 9 is indispensable for processing different folding cardboard dimensions.

REFERENCE SIGN LISTING

1 folding machine

2 central conveyor belt

3 conveyor speed

4 drivers

5 folding cardboard blank

6 middle section

7 fold groove

8 side part

9 reversible belt

10 longitudinal center

11 front area

12 folding device

13 folded edge

14 contact zone

15 drive

16 engine

17 chain

18 sprockets

19 sprockets

20 drive axle

21 chain pressing device

22 slider

23 holder

24 carriers

25 machine frames

26 bracket

27 Width of the deposit zone

28 Longitudinal center of the fold groove

29 circumferential folding straps

30 strap edge (folding) 31 belt edge (free)

32 guide device for support zone

33 guide rail

34 elastic bracket

35 stationary recording

36 rail counterpart, roller counterpart

37 spring

38 Leadership role

39 Continuous cot

40 chain guide rail

41 cross strap

42 Cutting level

43 entire funding route

44 axis

45 belt pulley

46 end pulley

47 end pulley

48 underside

49 carriers

50 sprocket

51 sprocket axle

52 feed station

53 inking station

54 slot station

55 creasing station

56 piles

57 folding station

58 longitudinal groove

59 raised length range

60 longitudinal web

61 front contact point

62 Curta outside

63 further spaced belt edge

64 closer spaced belt edge

65 increase 66 rear contact point

67 side edge

68 envelopes

A hinge axis of the rebate groove

B Groove width

C parallel to A

D Thickness of the material cut

Claims

PATENT CLAIMS

1. Device for processing a blank (5) conveyed along a conveying path (43) with a predetermined conveying speed (3),

wherein the blank (5) has a central part (6) on which a folding container is developed

laterally arranged side parts (8) are seated

for the manufacture of the folding container along the fold rillon (7) between the central part (6) and the side part (8) to the longitudinal center (10) of the blank (5) are pivoted inward and finally folded and connected to each other,

characterized in that

1.1 at least in the front region (11) of the conveying path, a folding device (12) engaging above and below the blank (5) is provided such that

1.2 on the top of the blank (5) a in the longitudinal direction of the groove (7) folding edge (13) is linear in the groove (7) that

1.3 on the underside of the blank (5) one to the

Folding edge (13) corresponding support zone (14) is formed, and that

1.4 the folding device (12) is driven synchronously with the conveying speed (3).

2. Device according to claim 1,

characterized in that

the folding device (12) engages the blank (5) at least in the front region (11) of the conveying path on which the side flaps (8) are pivoted inwards from an extended position by an angle of at least 60 degrees in each case.

3. Device according to claim 2,

characterized in that

the inward pivoting angle between the central part (6) and the side part (8) is between 60 degrees and at least 110 degrees.

4. Device according to one of claims 1-3

characterized in that

the folding device (12) is designed as a creasing station (55), to which fold grooves (7) are attached to blanks (5) which are still unfolded.

5. The device according to claim 4,

characterized in that

the creasing station (55) is a separate structural unit which is arranged between the feed station (52) and the folding station (57) of a folding machine (1).

6. Device according to one of claims 1-5,

characterized in that

Turning belts (9) rising from below to above and converging from outside to inside for swiveling the side parts (8) are provided with respect to the travel ranges of the folding grooves (7), which are provided with a front contact point (61) of their belt outside (62) in the front area of the side parts (8) and which are spaced further apart with one of their belt edges (63) from the rear region of the side parts than with the other of the belt edges (64), the reversing belts (9) there, preferably on one of the two belt edges (63, 64) on the further spaced belt edge (63) are provided with an elevation (65), the height of which is such that the side part (8) with its rear region also lies there and is guided in such a way (rear contact point 66) that the one to be pivoted inwards Side edge (67) prak table is held exactly parallel (A; C) to the groove (7).

7. The device according to claim 6,

characterized in that

the elevation (65) extends diagonally from the rear contact point (66) over the turning belt (9) to the front contact point (61), and that

the height of which decreases continuously up to the front contact point (61).

8. The device according to claim 6 or 7,

characterized in that

the reversing belts (9) are so entangled along the conveyor path that the front contact point (61) in the

Area of one belt edge and that the rear contact point (66) lies in the area of the other belt edge.

9. The device according to claim 7,

characterized in that

the elevation (65) extends along an essentially linear envelope (68) and falls from the envelope (68) to both belt edges in such a way that the envelope (68) lies linearly on its side part (8).

10. Device according to one of claims 1-9,

characterized in that

Fold edge (13) and support zone (14) on continuously rotating traction devices (chain, belt, belt (29, 39)).

11. The device according to any one of claims 1-10,

characterized in that Folding edge (13) and support zone (14) are formed directly by continuously rotating traction means (chain, belt, belt (29, 39)).

12. The device according to claim 11,

characterized in that

the folded edge (13) is formed by a belt edge (30) of a belt center running at the conveying speed of an endlessly rotating folding belt (29), the other belt drum (31) of which is related. of the blank runs back without contact.

13. Device according to one of claims 10 or 11,

characterized in that

the support zone (14) from the broad side (27) with one

Conveying speed running belt belt is formed.

14. Device according to one of claims 10 or 11,

characterized in that

Folded edge (13) and support zone (14) are formed by traction means, one of which is provided with a longitudinal groove (58) and the other of which is provided with a longitudinal web (60) engaging therein.

15. The device according to one of claims 10-14,

characterized in that

Guide devices (32) are provided between the end deflection rollers of the traction means strand forming the support zone on the underside thereof, for preferably elastic (34) pressing of the traction means strand against the underside of the blank (5).

16. The apparatus of claim 15,

characterized in that the guide devices (32) consist of elastically mounted rollers (38).

17. The apparatus of claim 15,

characterized in that

the guide devices (32) consist of an elastically mounted guide rail (33).

18. The apparatus according to claim 11,

characterized in that

the folded edge (14) is formed by transverse flaps (41) of an endless pad (39) running at the conveying speed.

19. The apparatus of claim 18,

characterized in that

the axes (51) of the sprockets (50) on the ends are essentially parallel to the plane (42) of the blank and perpendicular to the conveying direction (3), and that

the transverse links (41) point radially outwards with respect to the axis (51) away from the chain links.

20. The apparatus according to claim 18,

characterized in that

the axes (51) of the end sprockets (50) are essentially perpendicular to the plane (42) of the blank, and that

the cross brackets (41) are aligned essentially in the direction of the axes (51) and face the blank (5).

21. Device according to one of claims 1-20,

characterized in that

the folding devices (12) sit on each side on a support (24), and that

each carrier (24) is adjustable in the sense of a distance change from the respective opposite carrier (24).

22. The apparatus according to claim 21,

characterized in that

the corresponding support zones (14) have a predetermined width, within which the distance between the folded edges (13) can be changed.

23. The device according to one of claims 1-22,

characterized in that

the folded edges (13) lie in the longitudinal centers (28) of the fold grooves (7).

24. Device according to one of claims 1-23,

characterized in that

the folded edges (13) are rounded in a carton-friendly manner at their contact zones that come into contact with the blank (5).

25. A method for producing a folding container from a blank (5) conveyed at a predetermined conveying speed (3), on the middle part (6) of which are arranged laterally arranged side parts (8) which run along hinge-like fold grooves (7) by means of turning devices (9) the conveying path (43) is raised from the initially spread position, is increasingly pivoted inward along the fold grooves (7) towards the longitudinal center (10) of the blank (5), finally folded up from above and connected to one another,

characterized in that

the blank (5) along the fold grooves (7) linearly between a folding edge lying in the pivoting direction

(13) and one, the folding edge (13) opposite corresponding support zone (14) is clamped, and that

Folding edge (13) and support zone (14) at least during an inward pivoting movement of at least 60 degrees

Conveying speed (3) to be carried.

26. A method for producing a folding container from a blank (5) conveyed at a predetermined conveying speed (3), on whose middle part (6) laterally arranged side parts (8) are seated, with the middle part (6) and side parts (8) in the course of the conveying path (43) longitudinal grooves (7) are incorporated, characterized. that

the blank (5) for incorporating the fold grooves (7) is clamped in a line between the fold edge (13) lying in the conveying direction and a corresponding support zono (14) opposite the fold edge (13), the length of the clamping zone corresponding to the length of the fold groove and whereby the pinching zone is at least temporarily carried out at conveying speed.