The present invention relates to a method of packaging series of articles in different formations and is more closely defined in the preamble of claim 1. The invention furthermore concerns an apparatus for carrying out the method according to any method claim and is more closely defined in the preamble of the first apparatus claim.

The invention aims at packaging particularly bag-like packages containing e.g. instant soup ingredients, potato chips, instant tea and many other products, not only those belonging to the foodstuff sector, but to virtually any kind of products, and not only bags and packages, but also boxes and any other shape of articles and/or wrappings. The articles are being packed in two formations abutting and/or overlapping each other within an outer wrapping or package, preferably a carton which may be torn apart into two parts, each of which is holding one of said formations of articles, which thus won't have to be rearranged upon opening said carton or the like, but are ready for display, sale and use in this fashion.

A carton with packages as described above is previously known by EP-A-0 704 386. It will be appreciated, that this way of packa¬ ging saves a lot of space and thus packing material, as the one end portions of the packages are very thin and the packages are packed with these thin portions of two formations of packages facing and overlapping each other (Fig 3), whereby such over- lapping does not affect the total extension of either formation in stacking direction, as only the thinner portions overlap each other.

While such way of packaging generally is considered desirous and convenient as far as for instance use of available volume and outer packing material, transport, storage and display are con¬ cerned, little thought has been given so far to an advantageous mode of and apparatus for carrying out such packaging. A great problem is the practical adaption to the need for continuous change of the direction, in which the articles are to be stacked

in two different kinds of formation, the counting and grouping of both single articles and formations and the transport of such formations to packaging. In particular, so far there is no packa¬ ging machine or any suggestion or solution to achieve both high packing pace and safety for such way of packaging articles.

It is therefore an object of the present invention to provide a method and an apparatus for packaging series of articles in different formations. It is furthermore a particular object of the present invention to provide means for high packing speeds and simultaneously great safety and reliability of operation. It is, finally, an object of the present invention to improve known techniques in this field in various aspects.

These objects are achieved, according to the present invention, by a method of the initially defined kind being carried out as mentioned in the characterizing clause of claim 1. These objects are also achieved, according to the present invention, by an apparatus of the initially defined kind showing features as men- tioned in the characterizing clause of the first apparatus claim.

Further features of and advantages with the present invention are revealed by the following description with reference to the accompanying drawings, in which

Fig 1 shows a diagrammatical perspective view of a main part of a method or an apparatus according to the present invention,

Fig 2 shows, in greater detail, a corresponding view as Fig 1 of the overall concept of a preferred embodiment of the inven- tion,

Fig 3 is a magnified partial perspective view of part of Fig 2 and Fig 4 is a side elevational view of the parts shown in Fig 3.

In the drawings, the entire apparatus according to the present invention is designated by 1. It comprises two longitudinal conveyors 2, preferably endless belt conveyors, which are located on the same level, in parallel relation to but spaced apart from each other and are feeding packages 3 with bottom ends 4 and top ends 5 towards a receiving zone 6 common to both longitudinal

conveyors. A conveyor 2 is provided for each formation 71 of articles. An actuating means 7 is located across each conveyor establishing a stop zone 8 for stopped packages.

Each actuating means comprises a stop plate 9, which preferably is suspended from an actuating rod 10 forming part of an actuator 11, e.g. a pneumatic cylinder. The exact position of each stop plate is, of course, adjustable in a way as known per se, so that the length of travel of the packages on each conveyor and thereby the longitudinal distance between the planes of both stop plates can be adjusted, primarily for adaption to different sizes of ar¬ ticles to be handled. For certain special applications, the ang¬ les of each stop plate in vertical and/or lateral direction may also be adjustable to deviate from the ordinary 90° in relation to the conveyor plane and axis, respectively. The actuating means 7 are linked to sensors 12, e.g. photo cells, associated to each conveyor and linked to a computer unit 13 for detecting any mis- feed, either concerning the orientation of the packages in gene¬ ral or in relation to each other. In case of misfeed, the actua- ting means of the conveyor in question will pull up its stop plate, so that the misfed package(s) will pass across said stop plate on the conveyor to a collecting zone 14 for misfed packa¬ ges.

In front of each stop plate 9, i.e. upstreams each conveyor, there is provided at right angle across and above the latter a lateral conveyor 15, preferably an endless belt conveyor, having carrier plates 16. The lower part of these conveyors moves to¬ wards said collecting and stacking zone 6 between the two longi- tudinal conveyors, whereby said carrier plates are provided to transfer the articles travelling in longitudinal direction and stopped by said stop plates in lateral direction on to a horizon¬ tal receiving plate 17 adjacent each longitudinal conveyor and each stop zone 8 ahead of each stop plate 9.

Both receiving plates 17 are preferably located on the same level, which is slightly lower than the level of the upper part of the longitudinal conveyors. The difference between these two levels may correspond to approximately the maximum thickness of articles to be handled. Between each upper conveyor part and each

receiving plate 17, there is provided an angled guide plate 18, the one leg of which lies roughly within the same plane as said upper conveyor part, while the other leg is turned down. Both these latter legs define a duct 19 for collected and stacked articles. The width of said receiving plates 17 corresponds to somewhat less than the width of said duct, while the length of these plates, particularly if located on the same level, is roughly equal to or less than the length of each package. It is considered sufficient to have the plates carry part, e.g. 40 - 80%, of the length of packages only. Even a coverage of 40% only will retain a bag-like package on said plate, as the bottom part is considerably thicker and thus heavier than the top part.

The lateral conveyors 15 are in parallel relation to and may overlap each other slightly, while their lateral extension and thus the lateral extension of the carrier plates 16 preferably amounts to part of the length of packages only, for instance 20 - 90%, particularly approximately 60%.

Downstreams of each receiving plate 17, there is arranged, rough¬ ly in a vertical plane transverse to the receiving plate, a posi¬ tioning plate 20, the exact position of which may, of course, be adjusted. In operation, the positioning plate 20 is stationary, while the receiving plate is movable, firstly in a direction downstreams the respective adjacent conveyor and then back again to the extended position below the one end of the respective lateral conveyor above zone 6. The movement is effected by an actuator 21, e.g. a pneumatic cylinder with a rod 22 attached to the receiving plate in question. Each plate 17 may be withdrawn individually, i.e. as soon as an article has been dropped on to same or may both plates be withdrawn simultaneously, i.e. as soon as an article has been dropped on to each of them, so that by such a simultaneous movement, two articles are released at a time, which is particularly applicable in case of a considerable overlap between two formations of articles .

The duct 19 is laterally limited by said angled guide plates 18, one vertical leg of one plate is, however, not covering the en¬ tire side in question, but is reduced to vertical strips 23, be- tween which the free ends of the horizontal bars 24 of a gridlike

upper collecting means 25, e.g. a step lift, are insertable. This lift, which also may be called lowering means, is provided adja¬ cent said duct on its one side and is movable, with its bars 24 forming an intermediate platform for received and stacked packa- ges, into and out of said duct by means of an actuator 26, e.g. a pneumatic cylinder, with an actuating rod 27. Simultaneously with the receiving of articles, the upper step lift is movable downwards in steps 37 from an upper level 28 to a lower level 29, each step corresponding roughly to the thickness of a received package, with the aid of an actuating means 30 incorporating e.g. a pneumatic cylinder (not shown). Apart from said steps 37, the upper step lift travels transversely in one engagement step 43 in the upper position into said duct and in one disengagement step 44 in the lower position out of said duct and, finally, in one big step 45 from the latter position up to the upper (standby) position preceding step 43.

The lateral parts of the head ends of said duct 19 are enclosed by angled continuations 31 of said guide plates leaving a verti- cally throughgoing slot 32 in the centre for a bearing arm 33 of a lower collecting means 34, e.g. a step lift, which also may be called lowering means, and which can be lowered in steps 38 from an upper level coinciding with the lower level 29 of the upper step lift 25 down to a lower level 35 by means of an actuating means 36 incorporating e.g. a pneumatic cylinder (not shown). The steps 38 of the lower step lift are provided to continue from an upper position within said duct 19 downwards out of said duct and into a formation holder 39 of roughly corresponding form as said duct, i.e. with lateral surfaces 40, angled continuations 41 and a slot 42 at the head ends. In this case, there are, preferably, two uninterrupted surfaces 40, as there is no need for any hori¬ zontal penetration. Apart from lowering steps 38, the lower step lift is liftable from its lower level 35 up to its upper level 29 in one major single step 46 to its upper standby position.

While the said duct 19, apart from any adjustability, is statio¬ nary, the said formation holder 39 is movable in transverse di¬ rection away from both step lifts by means of an actuating means 47, whereby the formation holder passes over a sliding surface 48, which is located adjacent and between a platform 49 carried

by said bearing arm 33 and a dito platform 50 carried by a bea¬ ring arm 51, which belongs to an actuating means 52 of a transfer unit 53.

Above said unit 53, there is provided a stationary guide channel 54 of similar shape as the formation holder 39, above which channel 54 there is provided a transfer means 55, which has a similar form as the formation holder 39, but may be closed all around apart from the lower end, which is provided to receive a double formation of articles, as indicated in the drawings.

The transfer unit 53 is suspended from an actuating means 56, by means of which it is provided to travel above an annexed sliding surface 57, in a direction further away from both step lifts on to e.g. a carton blank 58, which is fed in position in the direc¬ tion of an arrow 59 from a carton stack 60, e.g. with the aid of suction means (not shown) as known per se.

A carton blank with e.g. a double formation with mutual overlap is then sucked down to a folding unit 61, only one side of which is shown in the drawings, which side consists of e.g. curvedly converging bars 62 bringing about automatic folding of the blank around the double formation along with other folding means, which are known per se and not shown here. A thus folded and sealed carton 63 is then moved on to further handling in the direction of the arrows 64 and 65.

All ducts, transfer units, holders etc may, of course, be desig¬ ned adjustable and/or exchangeable for various sizes of articles. The said packages include, preferably, as known per se, a central tear apart line 66 and a window line 67 surrounding a window 68. Firstly, the window is torn away and then the package is broken apart by bending the two package halves around said line or a part of said line e.g. 180°, whereby the two formations are se- parated, each to stay in its own half, which functions as a dis¬ play (see fig l a), b) and c)). Lines 66 and 67 consist, prefer¬ ably, of suitable perforations. Mere folding lines may consist of embossed grooves. The drawings also reveal several cuts as known per se delimiting various flaps.

While figures 2-4 show most features in great detail, fig 1 shows a simplified and somewhat modified embodiment, where the upper step lift may be withdrawn in a direction away from the lower step lift, i.e. the lower step lift extends below a double forma- tion of articles from one bottom end formation, while the upper step lift is insertable from the other bottom end formation. The receiving plates do each hold one article and are, preferably simultaneously, released, so that two articles overlapping each other fall down on to either a stack 72 of packages during build- up or on to the upper step lift as first packages . The purpose of the upper step lift is to receive part of a stack 72 of packages. During the time it takes to build up this part, the lower step lift is provided to move, preferably transversely, with a com¬ plete stack 72 of packages, usually two formations, on to a car- ton blank or to other means for holding and/or further handling. All of these features are, of course, also applicable on the embodiment shown in figures 2-4 or any other embodiment within the framework of this invention.

In either case, it is not mandatory to have the articles, single packages or the like overlap each other. Two formations may also abut each other bluntly, so that even articles, packages or the like having the shape of parallelepipeds may be covered by the present invention. On the other hand, there may be up to a 100% overlap or alteration of articles of any kind. Particularly in such a case, only one receiving plate for the articles coming from both lateral conveyors may be sufficient.

The apparatus 1 shown in figures 2 - 4 functions as follows: On the longitudinal conveyors 2, articles 3 travel in a first di¬ rection 69 and in a second direction 70, respectively, with their bottom ends 4 first towards the receiving zone 6. Their travel is monitored by sensors 12 and computer unit 13, as mentioned be¬ fore. Thanks to the concept of the invention, relatively high speeds are possible, for instance an article per second on each conveyor, which means a packaging pace of two articles per se¬ cond.

The articles are stopped by the respective stop plate 9. At high travelling speeds, an accurate positioning of the stopped arti-

cles is often not possible. Particularly airfilled packages tend to bounce slightly backwards, may be even slightly diagonally. The stopped articles are in this, often non-accurate, position taken away from the respective longitudinal conveyor in trans- verse direction by the respective lateral conveyor 15 by one of its carrier plates 16 and are thrown into the upper end of duct 19 on to the respective receiving plate 17.

As mentioned before, the two receiving plates may be withdrawn alternatingly or simultaneously thus dropping the articles one by one or two at a time. The dropping is not just a simple withdra¬ wal of the plate, but also an accurate positioning manoeuvre, as the article resting on its plate is drawn by the latter towards and against its positioning plate 20, whereby any space between the article bottom 4 and plate 20, due to non-accurate feeding or whatever further reasons there may be, is eliminated, so that a very accurate mutual positioning of both article formations is possible, usually at reduced speed, as the relatively high speed of the longitudinal conveyors partly is due because of the space between the articles travelling on same. An inaccurate mutual positioning of articles may cause either a concave hangdown or a convex buildup of the overlap zone of both formations, whereby deformations, damages and even breakdowns may be caused. Such inconveniences can easily be avoided by adjusting the positioning plate 20 appropriately.

When starting to collect and stack articles, the upper step lift 25 is inserted into duct 19 at the upper level 28. For each arti¬ cle or each pair of overlapping articles, the lift is lowered by one step 37, until the lower level 29 is reached, where the lower step lift 34 is waiting with its platform 49. Now, the upper step lift is withdrawn transversely by step 44 and upwardly by step 45 to the upper standby position annexed to duct 19, while the lower step lift is lowered in steps 38 down to level 35 corresponding to the pace of collection/stacking of articles. When the latter level is reached, the upper step lift is pushed into duct 19 again to receive part of the articles of a stack 72 in double formation, e.g. 4-12 articles altogether of a complete stack 72 of 8-50 articles. At that stage, the formation holder is filled with articles and will be withdrawn laterally by actuating means

47, above sliding surface 48 and on to platform 50 of transfer unit 53. Then, actuating means 52 will be lifted up through guide channel 54 and into transfer means 55 to the level of sliding surface 57, where actuating means 56 will move said transfer unit with a collected stack 72 of articles across sliding surface 57 and on to a carton blank 58, which then is e.g. sucked down into folding unit 61, where i.a. converging bars 62 will fold the blank to surround said collected stack 72 as a closed and sealed carton 63, which is fed to further handling and/or transport etc.

As soon as platform 50 has been lifted up above formation holder 38, the latter is returned by actuating means 47 to its starting position right below duct 19. Then platform 49 is lifted up again to upper level 29 awaiting receipt of a new part of stacked ar- tides released by the upper step lift, which accordingly fills the time gap it takes for the lower step lift to complete its task and the formation holder to transfer a complete stack 72 and return to its starting position.

All this enables high speed performance and greatest accuracy of all components.

The invention is not limited to the embodiments as described hereinbefore and shown in the accompanying drawings . Arbitrary modifications are, of course, possible within the scope of the inventive idea as outlined by the following claims. The lifts 25 and 34 may also be lowered continuously instead of stepwise.