DE3941139A1 - Sealing non-palleted stacks in film - by adding narrow layer to stack and forming recesses, drawing on film cover bonding inverting and repeating with second film - Google Patents

Abstract

A pack, which consists of a stack of articles without supporting pallet, is completely enclosed in plastic film by first stacking together layers of the same area and then adding a special layer so that at least two parallel recesses are formed for lifting features to engage later; a first cover of plastic film is drawn over the whole stack which is next turned through 180 deg.C so that the special layer/recesses are now underneath. A member which can be bonded to the film is applied beforehand to the recesses, and, when the stack has been turned through the 180 deg.C, a second film cover has been applied it is pressed and heated/bonded to the member concerned at the recesses so that the recesses are dressed cleanly and the first film cover lies firmly on the horizontal and vertical faces. ADVANTAGE - The method does not require extremely high strength material. It uses simple equipment and consumes little energy.

Description

The invention relates to a method for producing a completely covered with plastic film, palletless, ent several layers of stacked objects holding packaging unit, initially several Layers of objects with the same footprint above be stacked on top of each other, on which then a special layer of objects is stacked in such a way that at least two parallel niches for later attack are formed by support elements of a lifting device, thereon a first plastic film hood from above over the entire Stack is pulled, whereupon the entire stack by 180 ° is rotated so that the special layer with the niches comes down, taking over the first one Plastic film hood in the area of the niches an additional ches, connectable with the first plastic film hood Element is applied and that after rotating the Stack a second plastic film hood over the 180 ° Stack is drawn.

In a known method of this type (DE-PS 26 14 558 and 27 02 613) are plastic film covers made of shrink foil used, each of the two shrink wrap ben after pulling them over the stack Heat application is shrunk close to the stack. By  the double or successive opening shrink a shrink hood get the side faces such packaging is very stable. When opening the second hood will shrink between the air hoods welded to each other closed, creating a kind of "corrugated cardboard effect" poses. In addition, the additional plastic element the special layer in the area of the niches with the niches and the lowest normal layer into one essential stable base for the entire stack summarized and the niches are neatly shaped, so that injuries to the film in the niche area at late Ren attack of lifting elements are avoided. So ge The packaging formed shows excellent overall strength speed properties, so that the dimensional stability of the be relevant packaging units also particularly high bean sayings is fair, such as z. B. at very heavy cement bags and an approximately 10-fold envelope occur in overseas shipments.

It is also known to layer ge on a pallet stacked objects by covering a stretch film hood to connect to a manageable packaging unit the (DE-OS 27 06 955), here sufficient strength can be achieved if only a few manipulations of the ver Packing unit between manufacturing the same and Ver need to be incurred.

The object of the invention is to create a pallet The packaging is always the same as that mentioned at the beginning Kind that also have no extreme strength requirements needs to be met with a smaller apparatus and Energy expenditure.

In a method of the type described at the beginning, the se object achieved according to the invention in that stretch foil is used for the two plastic film covers and the first stretch film hood after pulling on the stack by pressing and heating at the same time or gluing in the area of the niches with the previously opened brought additional element so welded or ver is glued that the niches are clean, d. H., the stretch hood material of the first stretch hood in the vertical and horizontal boundaries of the niches is tight.

The use of stretch film hoods eliminates that described "corrugated cardboard effect" in the area of the pages surfaces of the finished packaging unit with resul lower strength properties. For that he is due to the elimination of heat shrinking much less equipment and energy Effort, because heat is applied either when gluing the first stretch film hood with the additional element  in the area of the niches can be omitted entirely or only in the area of niches is necessary to ensure that the one that initially runs diagonally over the niches Stretch film neatly to the horizontal and vertical Boundary surfaces of the niches formed or created becomes.

It may be sufficient if the additional element at least over a horizontal or vertical limit expansion area of each niche, because when gluing or welding the first stretch film hood in the area of these surfaces, the stretch film is then attached to the the boundaries of each niche create clean.

A particularly simple solution is characterized by that the additional element of two stiff stripes gene plates is formed on the horizontal surfaces of the niches. This strip-shaped plat must of course have sufficient rigidity have speed, they can be made of plastic, for example plates or consist of sufficiently thick cardboard. The strip-shaped plates advantageously have one slightly wider than the respective niche width, so that the panels stretch when applying the first film hood and the resulting compression of the stack at least in some areas in the area between the top normal layer and the special layer  stretch so that they are held there.

It has proven to be particularly advantageous to additional element to ver a rigid U-shaped tub turn, which is placed over the special layer that the base of the U-shaped tub is the top of the Special layer is applied while the bilateral legs the vertical surfaces of the niches. In further training it is particularly favorable if between the legs the U-shaped tub connecting plates are the vertical surface between the niches Chen the special layer because everything unwanted spreading of the legs of the U-shaped Tub in the niche area is safely prevented and thus no injury to the legs in question of the additional plastic element attached stretchfo lien material occur by attacking support elements can.

Furthermore, the vertical legs of the U-shaped connect horizontal legs to the tub, wel che the horizontal surfaces of the niches, such that gluing or welding both in the hori zonal and vertical boundary surfaces of the Niches is possible.  

You can also add one as an additional element Use stiff plate before applying the special layer on the top normal layer of the stack like this is imposed that the horizontal surfaces of the niches of this plate are covered. This variant is also particularly cheap because of the stiff arrangement Plate between top normal layer and special layer, whose position is securely fixed and thus the stretch film of the first stretch film hood after it has been glued or welding to the relevant rigid plate in the Horizontal area of the niches is kept safe.

A particularly simple and inexpensive embodiment is characterized in that as an additional element a flexible film is used between the top Normal layer and special layer is laid and at least at least beyond the edges adjacent to the niches himself in the area of the side faces of the stack stretches. By applying the first stretch films The flexible film is then hooded by relaxing the The stretch film hood adjoins the niches the edge area of the side surfaces of the stack ten, so that the flexible film in the horizontal Niche surfaces are firmly against the stack and thus the first The stretch film hood is shaped accordingly Niches can be fixed.  

Furthermore, the invention provides that the additional Element to be connected to the first stretch film hood the surface is provided with a hot melt adhesive, which ge by pressing a heated pressure element the first stretch film hood is activated. These Variant enables a particularly simple procedure process, as elements pre-assembled with adhesive Ver can find application and at the same time when pressing the Gluing takes place.

It is particularly advantageous if each of the two stretch film covers over the edge of the Stack is pulled so that the respective bottom of the stack is undercut. In further training it is particularly convenient if the lower edge of the second stretch film hood so far over the bottom the bottom normal layer of the stack is pulled that the stretch film relaxes in the being all over the horizontal niche surfaces lies. This training ensures that be particularly good strength properties of the stack straight in the corner areas result in special demands are exposed.

The invention is below with reference to the drawing explained in more detail, for example. This shows in:

Figs. 1 to 9 according to a schematic representation of the individual process steps of an execution example of the invention, and

Fig. 10 to 16 in a simplified perspective Dar each have a stacking position in front of the first to bring a stretch film hood, on a different, respectively applied to the first stretch film hood element connectable in the area of niches.

Fig. 1 shows a hood pulling device 1 , which next has a frame 2 . Within the frame 2 , a stack of goods 3 , which will be described in more detail below, is arranged on a lifting device 4 . On Ge stell 2 , a roller 5 is mounted on which a stretch film plastic hose is wound with gussets. The flat-lying hose 6 is fed via deflection rollers 7 and drive rollers 8 to a spreader device, generally designated 9 , below which a separating device and a welding device are arranged.

Below these devices, two roof-shaped double conveyor belts 10 are arranged on both sides of the frame 2 , such that the distance between their discharge ends can be changed to adapt to different cross-sectional dimensions of the stack of goods 3 .

Vertically displaceable on the frame 2 are hood pulling devices 11 , which in turn each have horizontally movable gripping elements 12 .

The stack of goods 3 (see also FIG. 10) consists of several stacked normal layers 13 of objects with the same base area, on which finally a special layer 14 of objects is stacked such that at least two mutually parallel niches 15 are formed. This palletizing of the respective stack of goods 3 takes place in one of the Haubenüberziehvor direction 1 upstream palletizing device, which is not shown in the drawing.

It can now be provided that an additional element 16 which can be connected to the first stretch film hood to be applied subsequently is applied to the stack of goods 3 in the area of the niches 15 before the stack 3 of goods is introduced into the hood covering device 1 . Alternatively, it is also possible to apply this additional element 16 only in the hood covering device 1 .

The process sequence will now be described below with reference to FIGS . 1 to 9:
In the state shown in FIG. 1, the stack of goods 3 with the special layer 14 with the niches 15 facing upward on the lifting device 4 in the hood covering device 1 , the additional element 16 already being applied in the area of the niches 15 . First, the stretch film tube 6 via the Vorspreizeinrichtung 9 and the double conveyor belts 10 will be spread without already a voltage is generated in the tube 6, which is indicated in Fig. 1 by the loop-like representation of the tube 6 in the region of the gripping elements 12. The hood covering devices 11 are in the upper position, at the same time the gripping elements 12 are moved horizontally inwards and engage in the stretched film tube 6 which is spread open.

Subsequently ( FIG. 2), the gripping elements 12 are moved horizontally outward in the direction of the arrow, in such a way that the stretch film tube 6 is spread out under tension and its outer boundary surfaces extend beyond the stack of goods 3 located below them. As can also be seen from FIG. 2, in this state the tube 6 has already been cut off and is closed at the upper end, forming a first stretch film hood 17 .

Subsequently, the stack of goods 3 is lifted and released by the lifting device 4 in such a way that at least the lower edge regions of the lowest normal layer are freely accessible ( FIG. 3), as a result of which the first stretch film hood 17, in the tensioned state, already covers the upper region of the stack 3 encloses.

The first stretch 17 is pulled over the entire stack by vertical movement of the cover pull-means 11 downwardly (arrows in Fig. 4) film hood, with the stretch film hood 17 creates in the upper portion of the stack 3 already relaxation fixed to the stack 3.

As shown in Fig. 5, the hood pulling lines 11 at the end of the hood pulling process with their gripping elements 12 are moved so far down that they are below the free stack 3 . By moving the gripping elements 12 horizontally inward, the first stretch film hood 17 is completely relaxed and accordingly lies against the stack 3 . Due to the exemption of the stack 3 by the Hubein device 4 , the underside of the stack 3 is undercut by the first stretch film hood 17 .

The stack of goods 3 is then moved downwards again by the lifting device 4 .

In order to form the niches 15 , pressure elements, which are denoted by 18 in the drawing, are inserted into the niche regions on both sides ( FIG. 6). The design of these pressing elements 18 may vary depending on the design of the additional element 16 . If an additional element 16 made of plastic is used, the pressing elements 18 are provided with additional heating devices, which ensures that the respective foil area of the first stretch film hood 17 is welded to the additional element 16 while forming the recesses 15 .

On the other hand, if an adhesive connection between the additional element 16 and the first stretch film hood 17 is provided, then only contact elements 18 are sufficient, the adhesive material then being brought up to the additional element before the first stretch film hood 17 is applied, for. B. in the hood pulling device 1 or in the upstream palletizing device.

In order to enable the additional element 16 to be pre-assembled with adhesive, a hot-melt adhesive coating can also be provided. In this case, the pressing elements 18 are designed to be heatable, with the adhesive then being melted at the same time as pressing and being glued accordingly between the additional element 16 and the first stretch film hood 17 .

After the formation of the niches 15 by connecting additional element 16 and the first stretch film hood 17 in the niche area, the stack of goods 3 is turned through 180 ° in such a way that the special layer 14 is at the bottom. This turning process can be carried out in a downstream th turning device, but turning devices can also be integrated in the hood pulling device 1 , which is not shown in the drawing and what is not important here.

As shown in FIG. 8, the stack of goods 3 is then freed up by the lifting device 4 with the son downward and in turn covered with a stretch film hood which covers the two stretch film hood 19 .

Fig. 9 shows the final state with the packaging unit completed. The second stretch film hood 19 is pulled so far over the lower edge of the lowermost normal layer of the stack 3 that when the stretch film relaxes, it essentially creates the entire surface of the horizontal niche surfaces ( FIG. 9).

Figs. 10 to 16 show different forms of execution of the additional element 16, wherein each ge is ensured that the additional element surface min least about a horizontal or vertical limiting extends each niche.

FIG. 10 shows a stack of goods 3 with an additional element, which consists of a rigid U-shaped trough 20 , to the vertical legs 21 of which horizontal legs 22 are connected. As can be seen, the U-shaped trough 20 is placed over the special layer 14 of the stack 3 in such a way that the base of the U-shaped trough 20 rests against the top of the special layer 14 , while the legs on both sides rest against the vertical surfaces of the niches 15 . This embodiment of the additional element ensures a particularly good niche formation, since the first stretch film hood to be applied is connected to the additional element both in the region of the horizontal and the vertical surfaces of the niches 15 . Here again, a welded joint can be seen if it is a plastic tub, or an adhesive connection if, for example, cardboard tubs or the like are used.

Fig. 11 shows another embodiment, here the additional element is designed as a rigid U-shaped trough 23 , wherein between the legs 24 connecting plates 25 are formed which lie against the vertical surfaces of the special layer 14 lying between the niches 15. The additional element is therefore formed from a cap.

In Fig. 12, a simplified design is shown, the additional element consists of a rigid U-shaped trough 26 which is placed over the special layer 14 such that the base of the U-shaped trough abuts the upper side of the special layer 14 , and legs 27 on both sides rest against the vertical surfaces of the niches 15 .

In the embodiment shown in FIG. 13, the additional element is designed as a rigid plate 28 , which is placed on the uppermost normal layer of the stack 3 before the special layer 14 is brought on in such a way that the horizontal surfaces of the niches 15 are covered by this plate. The attachment of the first stretch film hood takes place in this embodiment accordingly in the area of the horizontal surfaces of the niches 15 .

FIG. 14 shows a particularly simple embodiment which is particularly suitable for packaging goods with slightly rounded corners, such as cement bags or the like. The additional element here consists of two strip-shaped plates 29 which are placed on the horizontal surfaces of the niches 15 . If the first stretch film hood is now applied, the edge areas of the strip-shaped plates 29 will extend slightly due to the tension caused by the first stretch film hood into the region between the special layer 14 and the uppermost normal layer 13 , so that the strip-shaped plates 29 are locked there. This embodiment of the additional element is particularly simple and, above all, saves material.

Finally, an additional element is shown in FIGS. 15 and 16, which consists of a flexible film 30 and 31 , respectively, which is laid between the uppermost normal layer 13 and special layer 14 , the film extending into the region of the side surfaces of the stack 3 , at least in the area of the edges adjacent to the niches ( FIG. 16) or on all sides ( FIG. 15). This film can be made of plastic or else of fabric or the like. A weld or a bond to the first stretch film hood is then provided accordingly. A safe niche formation is guaranteed by the fact that the protruding edges hanging from the stack hanging downwards are pressed firmly against the side surfaces of the stack 3 by the relaxation of the first stretch film hood.

Of course, the invention is not limited to the exemplary embodiments shown in the drawing. Further refinements of the invention are possible without leaving the basic idea. Thus, in particular, the method shown in FIGS . 1 to 9 is also possible in a plurality of devices arranged one behind the other, that is to say, for example, with two hood pulling devices with an intervening turning device in a production line. It can also be provided that the pressing elements for forming the niches are easily seen in the turning device and the like. More.

Claims (11)

1. A method for producing a completely wrapped with plastic film, palletless, several layers on stacked objects containing packaging unit, first several layers of objects with the same footprint are stacked, on which then a special layer of objects is stacked such that at least two mutually parallel niches are formed for the later attack of support elements of a lifting device, a first plastic film cover is pulled from above over the entire stack, whereupon the entire stack is rotated through 180 ° in such a way that the special layer with the niches comes down, whereby before the covering of the first plastic film hood in the area of the niches, an additional element which can be connected to the first plastic film hood is applied and that after rotating the stack by 180 ° a second plastic film hood is pulled over the stack, thereby marked chnet that stretch film is used for the two plastic film hoods and the first stretch film hood after being pulled over the stack by pressing and simultaneous heating or gluing in the area of the niches with the previously applied additional element is welded or glued in such a way that the niches are neatly shaped, ie the stretch hood material of the first stretch hood fits tightly against the vertical and horizontal boundary surfaces of the niches. 2. The method according to claim 1, characterized, that the additional element is at least one hori zonal or vertical boundary surface of each niche stretches. 3. The method according to claim 2, characterized, that the additional element of two rigid strips migen plates is formed on the horizontal surfaces of the niches. 4. The method according to claim 2, characterized, that as an additional element a rigid U-shaped Trough is used, which over the special layer is turned over that the base of the U-shaped tub of the upper side of the special layer, while the two-sided Legs rest against the vertical surfaces of the niches. 5. The method according to claim 4, characterized, that an additional element is used, in which between  between the legs of the U-shaped tub connecting plate ten are formed that lie between the niches rest against the vertical surfaces of the special layer. 6. The method according to claim 4 or 5, characterized, that an additional element is used in which connect horizontal legs to the vertical legs which lie against the horizontal surfaces of the niches. 7. The method according to claim 2, characterized, that a rigid plate is used as an additional element is that before applying the special layer on the top normal layer of the stack is placed in such a way that the horizontal surfaces of the niches from this plate are covered. 8. The method according to claim 2, characterized, that a flexible film is used as an additional element is that between top normal layer and special layer is laid and at least over the to the Niches bordering out into the area of Side faces of the stack extends.   9. The method according to claim 1 or one of the following, characterized, that the element on the with the first stretch film hood Ver surfaces to be joined with a hot melt adhesive can be seen, which by pressing a heated pressure element activated against the first stretch film hood becomes. 10. The method according to claim 1 or one of the following, characterized, that each of the two stretch film hoods over each the bottom edge of the stack is pulled, such that the respective bottom of the stack is a bit below is gripped. 11. The method according to claim 10, characterized, that the bottom of the second stretch film hood so far over the bottom of the lowest normal layer of the Stack that is pulled while relaxing the stretch foil this essentially the horizontal niches creates areas all over.