METHOD AND DEVICE FOR MAKING PACKS

Abstract

A method for making packs of in each case at least two coupled articles which are held together by a strap wherein said strap is stretched in a horizontally manner about the outer surfaces of the articles. Said strap is laid about the articles during a continuous conveying process and fixed afterwards.

Description

This claims the benefit of German Patent Application 10 2009 040 700.6, filed Sep. 10, 2009 and hereby incorporated by reference herein.

The present invention relates to a method for making packs. Besides, the invention relates to a device for handling, conveying, packing and/or palletizing articles.

BACKGROUND

Various possibilities of combining single articles to larger packs are known. Thus, containers for beverages are for example combined and packed mostly by means of shrink films to packs of four, six or more containers. For the most part, the making of packs is inevitable since it is the most frequent type of sales units for containers of beverages and bottles made of PET plastic. The packs are partially once more combined for transport and/or assembled in layers and palletized.

The shrink films used for the making of known packs are in need of certain manufacturing steps with high energy demand. Furthermore, the used films cause costs regarding the making, the supply, the handling as well as the later disposal since after the sale they are not needed anymore. Likewise, the equipment of the device for the supply of so called film wrapping modules and other handling stations causes immense investment costs. Finally, a relatively high employment of capital is also necessary for the supply of the so called shrinking tunnel, whereby the film, which is wrapped around the packs by means of hot air impingement, is being shrinked.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a cost-saving and an easily manageable possibility for making packs which at least partially avoids the mentioned drawbacks of the prior art.

The present invention provides a method for making packs of in each case at least two coupled articles which are held together by strapping means wherein said strapping means is laid around the articles during a continuous conveying process and fixed afterwards. The articles are not stopped during the application of the strapping means since the strapping means is stretched around the articles according to the invention in a continuous process at a time, during which they are being continuously conveyed. The strapping means is preferably a strap which is stretched around the outer surfaces of the articles and afterwards fixed on each end in a pre-stressed state. Two or more straps running in a parallel manner can also form the strapping means, of course. Thus, the strapping means can be one, two or more straps made of rope material, wire, polymer, metal, paper or a composite material, which are fixed on its ends by gluing, welding, cramping, knotting or other.

The application of the strapping means can be carried out in a variety of ways. Thus, the strapping means can be lowered from above over the articles, for example, wherein said articles are positioned on a horizontal conveying means and are moved in a horizontal direction, and applied by the strapping unit wherein said strapping means moves synchronically with the feed rate of the strapping unit and the horizontal conveying means. Alternatively, the strapping unit can be provided with a gantry robot, or buckling-arm robot with strapping head, which moves during the application of the strapping means in vertical direction over the articles and simultaneously moves in horizontal conveying direction of the articles with said articles. The strapping unit can be optionally fixed in a stationed position, wherein in each case two separate straps with supply reels are arranged in such a way that they can be connected in the middle so that a horizontal strap is being stretched diagonally to the conveying direction of the packs. The pack is then moved continuously into this said stretched strap to the point until the rear edge of the formation is in line with the formerly even strap line. The movement of the formation of packs in conveying direction thus enforces a following conveyance of the straps from their supply reels so that the formation is now enclosed from three sides. If necessary, these reels can be provided with a self-powered drive and be controlled, for example, by means of light beams.

Besides, it is also possible that the strapping unit shifts or rotates the articles, which are bound to packs after the application of the strapping means onto the surface area of the horizontal conveying means for arranging the articles opposite to other packs and for the subsequent making of pallet layers and/or for the preparation of a palletizing afterwards. In such a way, the strapping unit can advantageously be a part of a grouping device and either be used for a desired grouping of the packs before they are being palletized or otherwise.

Another embodiment of the method according to the invention may provide the application and fixing of a carrier handle during or after the application of the strapping means onto the outer surface of the pack and/or onto the strapping means. If necessary, said carrier handle can contribute to the additional attitude stabilization of the formation of packs so that the containers of beverages can be slid against each other to a much lesser extent.

Furthermore, the invention relates to a device for handling, conveying, packing and/or palletizing articles. The device comprises at least one horizontal conveying means for continuously conveying articles, a device for making packs of in each case at least two grouped and coupled articles as well as a subsequent grouping device for arranging the packs opposite to other packs and for the subsequent making of pallet layers and/or for the preparation of a palletizing afterwards. The device for making packs is provided according to the invention with a strapping unit for the application of a strapping means wherein said strapping means is arranged horizontally and stretched onto the outer surfaces of the articles to be coupled together. The strapping unit is assigned to the horizontal conveying means and/or to the subsequent grouping device or can be an integral part of the horizontal conveying means and/or of the grouping device. The strapping unit can be optionally provided with a gantry robot, or buckling-arm robot with strapping head, which is movable during the application of the strapping means in vertical direction over the articles and is simultaneously movable in horizontal conveying direction of the articles with said articles.

The straps can either be made of suitable polymer material, metal or composite material. It is particularly advantageous to use a recyclable material which consists of mono-material polymer or of a defined metal, for example. If necessary it is possible to use biodegradable material, too. The positioning of the straps onto the packs can optionally be carried out mechanically or by means of air pressure. Thus, alternatives are possible with which the strap is being conveyed in parts along its transport path by means of air pressure so that said strap largely positions itself around the pack in the desired position and is supportively carried mechanically.

An advantage of the invention to known prior art is among other things the fact that the strapping means are less expensive than a film. No shrinking tunnel is necessary, which results in high energy saving and a reduction of the investment costs. When arranging the modules, the so called blocking, a smaller installation surface is necessary. In addition, not value adding functions such as transport, conveyance or the like can be reduced. Furthermore, the invention enables the avoiding of downtimes of the equipment and an increase of efficiency. On the basis of the modular design of the equipment parts, a modular installation facilitates to increase the lot sizes in production.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present invention shall now be described in greater detail according to the accompanying figures in the following detailed description. The dimensions of the individual elements to each other do not always correspond with the real dimensions since some forms are shown simplified and other forms are shown enlarged with respect to other elements for the sake of clarity.

FIG. 1 shows a schematic perspective view of a dividing system as well as a transfer onto a conveyor belt for linear container formations.

FIG. 2 shows a schematic perspective view of both a container division and of two strapping modules for double-lane mode.

FIG. 3 shows a further view of the embodiment according to FIG. 2.

FIG. 4 shows a top view onto the device according to FIG. 3.

FIG. 5 shows another top view onto the arrangement with removed base frame.

FIG. 6 shows a further perspective view onto the arrangement with removed base frame.

FIG. 7 shows a perspective view of an arrangement with direct blocking of the strapping unit with a grouping station of a palletizing machine.

FIG. 8 shows a perspective embodiment of an alternative strapping unit with stationary mounted strapping reels.

FIG. 9 shows in four successive views the production steps when making a pack with a strapping unit according to FIG. 8.

DETAILED DESCRIPTION

Same elements refer to same reference numbers throughout the various figures. Furthermore, only reference numbers which are necessary for the description of the respective figure are shown in the various figures for the sake of clarity. The shown embodiments are only examples of how the method according to the invention can be designed and shall not be regarded as limiting the invention.

As for the method described in the following, packs and sales units respectively are being formed by strapping of containers by means of strings, straps made of different materials such as paper, polymer, metal, rubber and the like of rigid or flexible type. In the following, a possibility is described regarding how to integrate strapping applicators, which are manually loaded with products, from the package strapping into the machine technology of packaging conveyor lines. With ‘container strapping’, the strapping type at hand, basically all possible geometric arrangements of the containers are conceivable: linear matrix arrangement in a ‘n times m’-arrangement of lines and columns for round or rectangular, square or other containers as well as, for example, close packings at an angle of 30° and 60° degrees respectively with round articles in any desirable number. The arrangement of the packs depends on the feeding of the containers by means of the so called container divider.

The idea for the invention is based upon the integration of strapping applicators in packaging conveyor lines, for example in one of the ways described in the following. The containers (round, rectangular or mould containers) to be strapped are divided into lanes by means of container feeders and conveyed to a container formation unit, for example a crank divider. The container formation unit forms container groups, which are fed to the strapping zone via a conveyor belt, out of the containers conveyed from the lanes. As for linear formations, the transport of the containers is carried out on the conveyor belt without guard railing and advance arbors. For products which are difficult to process or with diagonally staggered arrangements of packs, the transport of the containers through the strapping zone is carried out past the divider by advance arbors and railings. Diagonally staggered arrangements of containers, so called close packings, are formed by means of attachments onto the advance arbors.

The schematic view of FIG. 1 shows a dividing system 10 and the transfer onto a conveyor belt 12 for linear container formations. After forming desired pack formations 14 by means of a container divider and bringing the formations 14 in a defined distance by the divider, the grouped container formations pass 14 on a conveying means 16 the so called strapping zone 18 without relative motion between conveyor and formation. The strapping zone 18 consists either of minimal one strapping robot, also described as strapping module 20 in the following, or of a random number of successively loop-connected strapping modules 20 dependable on the required line efficiency. The processing and strapping respectively of the container formations can be carried out in the strapping modules 20 single-lane or multi-lane.

FIG. 2 shows a container dividing system 10 and two strapping modules 20 for double-lane mode.

As can be furthermore seen from FIG. 3, a strapping module 20 consists of a frame 22 and base frame respectively, into which two X and Z vertical axis are integrated. On each X an Z vertical axis, wherein said X and Z vertical axis are two linear axes with linear guiding and toothed belt drive, a so called strapping applicator 24 is mounted.

The X axis of the double axes portal moves in container feeding direction, the Z axis in vertical direction; please see FIG. 4.

The method for strapping the packs is described in the following, wherein reference is made to FIGS. 1 to 4. The container formations 14 are transported on the conveying means 16 by the strapping modules 20. In each case a defined gap exists between the container formations 14. After the entry of a container formation 14 in a strapping module 20, the strapping applicators 24 move with the X and Z portal axes over the respective formation 14, synchronize with the X axis regarding the feeding speed of the conveying means 16 and lower via the Z axis onto the strapping level. While the strapping head 24 moves with the container formation 14, the formation is strapped by means of straps 26, what can be seen from FIG. 5. The base frame has been removed in FIG. 5 for the sake of clarity. Optionally, the strapping means can be a single strap 26. Ideally, however, the strapping means consists of several overlapping straps 26 which are spaced from each other.

FIG. 6 shows strapping application heads 24 with two strapping units 28 on top of each other. If the strapping unit consists of several strapping modules 20 (in this case: two modules shown), then the first module straps a formation row and allows the second formation row or, if necessary, the umpteen formation row to pass through. The second formation row or umpteen formation row is then being strapped by the second strapping module or umpteen strapping module 20. Likewise, the base frame is removed in FIG. 6.

As for the above shown machine technology also alternative embodiments are possible. Thus, the strapping application heads 24 can also be carried by buckling-arm robots instead of gantry robots. Thereby, the basic functional process does not change. Such buckling-arm robots can be arranged next to the conveyor means in any desirable number.

One option can be the provision of the strapping application head with a strapping head for the application of carrier handles made of plastic straps. These carrier handles can be carried out in a self-adhesive manner, for example.

The strapping modules are very suitable for the integration into packaging systems 30. Thus, the strapping modules 20 can be integrated with the respective feed into conventional packaging-production lines as so called “stand-alone”-machinery. However, also the blocking of the strapping machine 31 with the palletizing machine 32 is possible. Thus, FIG. 7 shows a direct blocking of the strapping unit 31 with the grouping station 34 of a palletizing machine 32. Emerging packs from the strapping unit 31 are conveyed directly into the grouping station 34 which results in an advantageous process integration.

On the other hand, a further embodiment can be that the strapping application heads are integrated in the grouping station 34 of a palletizing machine 32. Before, during or immediately after the strapping of the packs, said packs are being grouped and brought into the desirable position on the conveying means 16 according to a given position scheme. Thus, it is also imaginable that the grouping station 34 with the integrated strapping application heads fulfils two tasks during a direct blocking in a packaging system, namely the making of packs and the grouping of packs to a pallet which can be palletized.

A further alternative to the shown machinery technology can be the stationary position of the strapping reels 36, as shown in FIG. 8. In this connection, in each case two separate straps with supply reels 36 are arranged in such a way that they are welded in the middle so that a horizontal strap 26 is stretched diagonally to the conveying direction of the packs 14. The pack 14 is then moved continuously into this said stretched strap 26 to the point until the rear edge of the formation is in line with the formerly even strap line. The movement of the formation of packs 14 in conveying direction thus enforces a following conveyance of the straps 26 from their supply reels 36 so that the formation 14 is now enclosed from three sides. It can also be advantageous, if these reels 36 can be provided with a self-powered drive and actively provide the necessary line capacity after a respective signalizing (for example light beam signals ‘leading edge pack arrives’), so that the tension forces can be minimized on the formation in the movement period. When the pack 14 is enclosed from three sides with the strap 26, the two fastening carriages 38, which are arranged on the left and on the right next to the conveying line of the packs 14, approach each other in one cutting stroke. The portal, onto which the fastening carriages 38 are conducting their closing in Y direction, must now simultaneously move together in conveying direction X with the pack 14 in order to enable a continuous flow. The fastening carriages 38 stretches the strap 26 around the formation and are sealing said strap. Simultaneously, the ends of the strap are cut off and sealed so that an even strap for the next pack is again provided. The portal with the fastening carriages 38 moves in opposition to the conveying direction back into its initial condition.

The consecutive procedural steps are once again shown from top to bottom in the embodiment of FIG. 9.

Depending on the requested capacity, the container formations which are to be strapped in a parallel manner can be strapped by feeding of two, three or more formations with a respective number of strapping applicators.

The invention has been described with reference to preferred embodiments. To the person skilled in the art it is also conceivable, however, to make changes and modifications to the invention without leaving the scope of protection of the appended claims.

LIST OF REFERENCE NUMBERS

• • 10 dividing system
  • 12 conveyor belt
  • 14 pack, container formation
  • 16 conveying means or conveyor
  • 18 strapping zone
  • 20 strapping module
  • 22 Frame
  • 24 strapping applicator, strapping head
  • 26 strap, strapping means
  • 28 strapping unit
  • 30 packaging system
  • 31 strapping unit
  • 32 palletizing device
  • 34 grouping station
  • 36 strapping reel
  • 38 fastening carriage

Claims

1. A method for making packs, each pack having at least two coupled articles, the method comprising: laying a strapping means around the articles during a continuous conveying process, the strapping means being arranged horizontally and stretched onto outer surfaces of the articles; and thenfixing the strapping means so that the articles are held together by the strapping means.

2. The method as recited in claim 1 wherein the strapping means is applied during the continuous conveying of the articles in a continuous process around said articles.

3. The method as recited in claim 1 wherein the strapping means includes a strap stretched around the outer surfaces of the articles and afterwards fixed on each end in a pre-stressed state.

4. The method as recited in claim 1 wherein the strapping means includes a plurality of straps stretched around the outer surfaces of the articles and afterwards fixed on each end in a pre-stressed state.

5. The method as recited in claim 3 wherein the strap is made of rope material, wire, polymer, metal, paper or a composite material fixed on its ends by gluing, welding, cramping, knotting or other.

6. The method as recited in claim 1 wherein the strapping means is lowered from above over the articles, wherein said articles are positioned on a horizontal conveyor and are moved in a horizontal direction, and the strapping means is applied by a strapping unit wherein said strapping means moves synchronically with a feed rate of the strapping unit and the horizontal conveyor.

7. The method as recited in claim 6 wherein the strapping unit is provided with a gantry robot, or buckling-arm robot with a strapping head, which moves during the application of the strapping means in a vertical direction over the articles and simultaneously moves in a horizontal conveying direction of the articles with said articles.

8. The method as recited in claim 6 wherein the strapping unit shifts or rotates the articles that form the packs, after the application of the strapping means onto the surface area of the horizontal conveyor for arranging the articles opposite to other packs and for the subsequent making of pallet layers and/or for preparing a palletizing afterwards.

9. The method as recited in claim 1 further comprising applying and fixing a carrier handle during or after the application of the strapping means onto the outer surface of the pack and/or onto the strapping means.

10. The method as recited in claim 1 wherein the strapping means is a strap or string.

11. A device for handling, conveying, packing and/or palletizing articles, comprising: at least one horizontal conveyor for continuously conveying articles;a device for making packs of in each case at least two grouped and coupled articles; anda subsequent grouping device for arranging the packs opposite to other packs and for the subsequent making of pallet layers and/or for the preparation of a palletizing afterwards;the device for making packs including a strapping unit for the application of a strapping means wherein said strapping means is spun in a horizontally manner around the outer surfaces of the articles to be coupled together, the strapping unit being assigned to the horizontal conveyor and/or to the subsequent grouping device, or integral with the horizontal conveyor and/or of the grouping device.

12. The device as recited in claim 11, wherein the strapping unit includes a gantry robot, or buckling-arm robot with strapping head, movable during application of the strapping means in a vertical direction over the articles and simultaneously movable in a horizontal conveying direction of the articles with said articles.