CA1187056A

CA1187056A - Filled container end seal folding system with intermittent motion conveyor

Info

Publication number: CA1187056A
Application number: CA000399259A
Authority: CA
Inventors: Stig A. Lothman
Original assignee: Tetra Pak International AB
Current assignee: Tetra Pak AB
Priority date: 1981-03-27
Filing date: 1982-03-24
Publication date: 1985-05-14
Also published as: FI71283B; AU545937B2; ATE20013T1; SE8101974L; NO156934C; EP0061663A3; JPH044210B2; EP0061663A2; NO156934B; DK133382A; NO820998L; FI821079A0; FI821079L; AU8196582A; DK154409C; SE436272B; EP0061663B1; DE3271322D1; JPS57175538A; DK154409B

Abstract

ABSTRACT OF THE DISCLOSURE

A machine for the processing of packing containers of the type used for example for milk products. Such packing containers are manufactured from a filled material tube and are first given cushion-shape. By use of the machine in accordance with the invention they are subsequently converted to a substantially parallelepipedic shape. The machine comprises a transport means in the form of a wheel having radial holding devices for the cushion-shaped semi-finished products. The transport means can be rotated stepwise so that each individual packing container passes around processing stations disposed around the periphery of the transport means for the folding of corner lugs, sealing and shaping.

Description

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The present invention relates to a machine for the processing of packing cor.tainers comprising a drivable trans-port means for moving the packing containers between different processing stations.

;In the manufacture of non-returnable pacXages for liquid~ goods and the like a material web of a flexible, - but substantially shape-retaining, laminated material is used which comprises layers of paper, thermoplastics and possibly aluminium foil. The material web is supplied in the form of a roll to a packing machine which successively converts the material web to a tube or hose by sealing the longitudinal edges of the web to one another. This liquid-tight tube is filled with contents, whereupon it is divided into individual, substantially cushion-shaped packing containers by compression and sealing together along zones at equal distance, extending transversely over the tube. The packing containers so obtained are formed in conjunction with the said compression and sealing together to substantially parallelepipedic units, which are seaprated from each other by cuts in the transverse sealing zones. The parallelepipedic shape is disturbed, how-ever, by the said sealing zones converted to projecting sealing fins as well as by four triangular, double-walled corner lugs which for reasons of geometry are formed by excess material during the conversion from cushion-shape to substantially parallelepipedic shape.

Each individual packing container is then e~e~
further to a machine, possibly~- ~ together with the main 3Q packing machine, for the processing (so-called final shaping or final folding) of the packing containers. In such a machine, inter alia, the seal~ng fins as well as the corner lugs are folded in against ~ joined to the container body proper so that a packing container of a more correct parallele-pipedic shape is produced.

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This processing or final foldiny of each indiviaual packing container manufactured by the packing machine takes place successively, each packing container being moved between and being processe(~ in different processing stations 5 in the final folder, the time for the whole processing cycle being determined, inter alia, by the heat-sealing times of the thermoplastic material, which makes it difficult to design a final folder which operates at sufficiently high speed to serve fast packing machines.
The movement of the more or less finished packing containers step-by-step also makes high demands on accuracy, if it is to be ensured that each packing container is moved to the exactly correct processing position at each station.
a ~G~ s Previously used final folders cannot process the containers with sufficient accuracy and safety at the high speeds of operation which are required in modern packing machines, and it is therefore in general desirable that a faster and more accurately working final folder should be designed~

The present invention therefore provides a machine for the processing of packing- containers which is subject to 25 the disadvantages of earlier designs, but works safely and rapidly.

The present invention also provides a machine of the abovementioned type which ~ ~ moves and guides the 3Q packing containers between accurately fixed ~ in each processing station.

The present invention also provides a machine which is capable of performing a safe and accurate folding and forming of sealing fins as well as corner lugs.

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The ~resent invention finally provides a final folder which in spite of making it possible to extend the processing time in each indiviclual processing station has a high overall capacity.

In accordance with the present invention there is provided a machine for the processing of packing containers CQmprising a drivable means of transport for the moving of the packing containers between different processing stations, the means of transport comprising an intermittently rotatable drum which along its periphery is provided with holding devices for individual packing containers, said holding devices being arranged at a mutually uniform pitch which corresponds to the pitch between the processing stations fixed around the means of transport, and adapted so that during rotation of the drum they are manoeuvred between an open and a closed position, wherein each holding device comprises a pair of jaws extending substantially radially in relation to the drum and being capable to be brought into a closed position in which the dis-tance between these jaws corresponds with the respective sizeof the packing container to be interposed between them, and out of this closed position into an open or partially open position in which the packing container can be moved in a radial direction between said jaws by means of external forces, and wherein guide rails are situated at a distance from one another, extending along the path of movement of the holding device, which are adapted so that on rotation of the drum, in at least a prefolding station they cooperate with corner lugs of the packing containers to be folded against container walls, external forces being made effective in the prefolding station by a folding plate which is movable substantially in the radial direction of the drum from a rest position out-side radially outer guide rails to an effective or active positi~n between the outer guide rails the jaw being adapted to be brought, in the prefoldin~ station, into the partially open p~sition.

~f ~ 3 -The machine in accordance with the invention for the processing or ~inal folding of packing containers not only provides a very high working speed, but al.so makes it possible to increase the available processing time at each station, at the same time as the machine guarantees a safe removal of the partially processed packing containers bet-ween acc~lrately fixed positions at each processing station.
The machine in accordance with the invention also provides a safe guidance of the packing containers during the transport between the processing stations and ensures finally that the folding-in of the corner lugs takes place step-by-step in a well-defined and accurate manner.

The present invention will be further illustrated by way of the accompanying drawings which show schematically a preferred embodiment of the machine in accordance with the invention where for the sake of clarity only the details required for the understanding of the design and function of the machine have been included and in which:
Fig. 1 is a side schematic view of the machine in accordance with th~ invention as arranged at and coupled to a packing machine of the conventional type;

Fig. 2 is a perspective of the main unit or final folding unit of the machine in accordance with the invention;

Fig. 3 corresponds substantially to Fig. 2, but shows the driving system of the final folding unit;

Fig. 4 is a side elevation of a transport means mounted on the final folding unit;

Fig. 5 is a side elevation of the final folding station of the machine;

- 3a -Fig. 6 is a perspective view of the final folding station according -to Fig. 5; and Figs. 7-13 show the processing and forming of a packing container during its travel through the machine in accordance with the invention, Fig. 7 showing the package in a feeding-in station, Fig. 8 showing the package during its removal from the feeding-in station, Fig. 9 showing the package in a prefol~ing station, Fig. 10 showing the package in an adhasive station, Fig. 11 showing the package in a final folding station, Fig. 12 showing the package in a ready-shaped condition after the final folding station and Fig. 13 showing the finished packing container in a feeding-out station, wher~ it is discharged from the means of transport of the final folding unit.

In Figure 1 the machine is arranged at and connected to a conventional packing machine, of which only a limited part 1 is shown~ The machine is adapted to take in hand and to finish packing containers 2 delivered from the packing machine 1 and it is driven synchronously with the packing machine 1 by means of a driving shaft 3 which connects the machine to a power take-off 4 in the packing machine.
The machine may be divided int~ three main units, namely a final folding unit 5 proper wherein the successive processing of the packing container taken in hand is taking plane, a transportation unit 6 for the conveying of the pack-ing container 2 from the packing machine 1 to the final folding unit 5, and a power transmission .~

- 3b -'t and driving uni.t 7 for -the drivi.ny of the final folding unit 5 and the conveying unit 6 synchronously with the packing machine 1. The power transmission and driving unit 7 is situated lowermost in the machine and constitutes at the same time a foundation for the other units. ~he -transpor-tation unit 6 is situa-ted between -the packing machine 1 and the final folding unit 5 space being provided undernea~h the transportation unit 6 for a conveyor 8 moun-ted above the driving unit 7, which extends at right-angles to the transportation unit 6 and is adapted for the removal o~
finished packing containers 2 from -the final folding unit 5 for the further -transport to a packer which collects a num-ber of individual packing containers 2 in-to a larger collec-tive package in order -to facilitate -the further transpor-t to the consumer.

The transportation unit 6 comprises a frame 9 which has two parallel elongated sidewalls be-tween which the packing contai.ners are conveyed from the packing machine 1 to the final folding unit 5 by means of an endless main con-veyor belt 10 which moves around pulleys/ arranged at both ends of theconveying unit 6, and which are supported so that they can rotate freely between the two parallel sides of the frame 9. The end pulley 11 is connected to a driving motor (not shown) and serves a-t -the same -ti.me as an end pulley for a further conveyor belt 12 which is designed as a receiving conveyor belt for the packing containers delivered from -the packing machine 1. The receivi.ng conveyor belt 12 as well as the main conveyor belt 10 comprises a grea-t number of parallel bel-ts which are arranged with gaps between them, sufficient to allow them to pass over the common end pulley 11 without interfering with each other.

The main conveyor belt 10 e~tends substantially horizontally or slightly upwards towards the final folding unit 5, whilst the receiving conveyor belt 12 slopes in the opposite direction and, more particularly, extends up~ards towards -the packing machine 1 at an angle to the horizontal plane which amoun-ts to approx. 30. As a result -the partially formed packing con-tainers, fed-out from the packing machine 1 will, after a short distance of free fall, land and be checked gentl.y by the sloping conveyor belt 12, whereupon -they are transferred directly to the main conveyor belt lO
to be moved on in the direction of the final folding unit 5. At the end of the main conveyor belt 10 facing towards the final folding unit 5 a feeding-out conveyor belt 13 situated above the same is provided~ which moves i.n the same main di.rection as the main conveyor belt lO, but is situa-ted at a dis-tance above the same which substantially cor-responds to or slightly exceeds the height of the packing con-tainers transpor-ted on the main conveyor bel-t 10. Whilst the main conveyor bel-t 10 and the receiving conveyor belt 12 are driven at a uniform, constant speed, the feeding-out conveyor belt 13 is driven a-t a constant speed which is twice the speed of the main conveyor belt lO. With the help of a Einger 14 projecting from the conveyor ~elt 13 the feeding-out conveyor belt 13 takes over the feed of the packages arriving on the main conveyor belt 10 and moves the same at twice the speed over the final stretch from the main con-veyor belt 10 and over to the final folding uni.t 5. As a result the packages transferred successively to the final folding unit 5 will be "separa-ted" so that the in-terval be-t-ween them becomes grea-ter than the interval between -the pack-ing containers fed along the main conveyor belt 10 which is impro-tant for the func-tion of the final folding unit, as will be explained in more detail in the following.

The power transmission or driving unit 7 located underneath the transportation unit 6 extends from the lower end of the packing machine 1 and in, underneath the final folding unit 5 proper. The power transmission unit 7 com-prises an open part, shown to the left in Figure 1, wherein . ~

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runs the driving shaf-t 3 which connects the power takeoff of the pac]cing machi.ne 4 to a closed transfer gearbox 15, shown on the right in Figure 1, which a-t the same time constitutes the foundation for the fi.nal folding unit 5. The open part of the power transmission uni-t 7 comprises two parallel sides and a base and in the main has three functions, namely in the first place -to prevent contact with -the driving shaft : 3, secondly -to fix the final folding uni-t at a correct dis-tance from -the packing machine 1 and thirdly to serve as a collecting trough for liquid contents which e.g. may leak from the packing containers. The driving shaft 3 connects via suitable couplings and gearboxes (not shown) the driving motor of the packing machine to the driving system of the final folding unit 5, so that the final folding uni-t auto-15 matically can be driven synchronously with -the packing machine. It is also possible -to dri.ve -the ~inal folding unit 5 by means of a separa-te dri.ving motor (not shown) which makes possible, for example, opera-tion of -the final folding unit 5 and the transportation unit 6 after -the main packing machine 1 has been stopped.
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The actual rnain portion of the machine in accor-dance with the i.nvention, tha-t is to say the final folding ; unit 5, has a foundation which in its lowest part accommo-25. dates -the transfer gearbox 15 mentioned earlier. Above this . there is a second gearbox which comprises an indexing gear j 16, and above this there is a further gearbox cornprising an upper mitre gear 17. The driving shaf-t 3 extending through the power transmission uni.t 7 is connected via a coupling to : 30 an incoming shaft lB in the transfer gearbox 15 (Fig. 3).
The incoming shaft 18 runs horizontally into the transfer gearbox and drives a lower mi-tre gear 19 and a rear mitre gear 20. The rotation of the incoming shaft 18 is trans-ferred via the rear mitre 20 -to a lower shaft 21 also situa-ted horizontally but a-t a right angle to the incoming shaft 18, which, via operating cams 22 a-t both its ends converts ' ~'7q~

-the movement to a reciprocating oscilla-ting motion of two operating arms 23 mounted so -that they can oscillate in the transfer gearbox, the function of which will be described in detail in the following.

The rota-tion of the incomi.ng shaft 18 is transmit-ted further via the lower mi-tre gear 19 mentioned earlier to a transfer shaf-t 24 extending vertically through the final folding unit 5. The transfer shaft 24 drives -the indexing gear 16 via a mitre gear so that the rotation of the transfer shaft 24 is converted to a repea-ted turni.ng move-ment or indexing of l/6th turn of an intermedi.a-te shaf-t 25 projecting on either side of the indexing gearbox. From the indexing gearbox -the rotation is -transferred via a further cutout by way of -the upper mitre gear 17 to a horizontally si-tuated upper shaLt 26 which is provided on both ends with cams 27, -the function of which wi.ll be described in -the following.

The ir-coming shaft 18 is also.provided, finally, with a feed cam plate 28 which via a cam follower 29 drives a feed assembly 30 mounted so tha-t it can oscillate outside the transfer gearbox. The feed assembly 30 com~ri es -two sub.stantially vertical arms 31 extending on either side of the driving shaft. The arms 31 are supported by -two.parallel shafts 32 which are bo:th supported so.tha-t -they can rotate .in the end wall of the transfer gearbox 15. However, one of the shat 32 extends with its one end in-to.the transfer gearbox where it supports the cam follower 29. Via this shaft the feed assembly 30 can be actuated in a reciprocating oscillating movement. The two oscillating arms 31 suppor-t at their upper part a feeding-in device 33 and a feeding-ou-t device 34 which are in parallelogram suspensi.on in the arms 31. The function of the -two feeding devices 33,34 will be described in the following.

The transfer gearbox 15 is designed as anoil -trough : - 7 -~i7~
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and partially filled with oil whi.ch is supplied by means of pumps (not shown) to the di.fferent movable parts located in the fi.nal folding unit such as shafts, mitre gears, etc.
To prevent any oil leakage and contamination of the packing containers handled in the final.folding unit 5, the driving system mentioned above and described in connection with : Figure 3 is wholly closed.

The machine will now be described in detail with special reference to Figure 2, which shows the final folding unit 5 i-tself in perspective. It is evident from -the Figure how the foundation described earlier, consisting of the transfer gearbox 15, the indexing gear 16 and the upper mitre gear 17, supports two.rotatable means of transport lS 35. The two means of transpor-t 35 each comprise a cnntrally ~ situated rota-table drum 36 which is firmly attached to.the end of -the intermedi.ate shaf-t 25 projec-ting from the indexing gearbox housi.ng 16. The two.means of -transport 35 are mutually identical (so that in the following only one will be des-cribed) and are situated axi.ally in line with one another on either side of -the indexing gearbox 16. It is the task of the means of transport 35 to.remove the packing con-tai.ners supplied bia the transportation unit 6 (Fig. 1) between dif-feren-t processing stations i.n -the final folding unit and the 2S means of -transport is provided to.this end w.i-th a number of holding devices 37 situa-ted at a uniform pitch around the drum 36, each of which comprises a fixed and a movable jaw, 38 and 39 respectively, (Fig. 4~ which between substantially plane working surfaces facing to.wards each o:ther form a space adapted to.the size of the packing container 2. Each fixed jaw 38 is substantially L-shaped, the longer leg of the L forming the said working surface whi.ch ex-tends sub s-tan-tially radially i.n relation to.the drum 36 whilst the shorter leg ex-tends at an angle of 90 to -the worki.ng sur-face so.tha-t -the said shorter leg in effect forms the base 40 of the holding device 37. In the base a cutout is provided ~ ~3 ~'7~S6 to. accommodate a sealing fin on the packing containers. The r fixed jaw 38 is firmly attached with its shorter leg to the drum 36. The Movable jaw 39 is supported sO that it can pivo:t about an axle 41 extend,ing parallel wi-th -the centre axle of the drum. More par:ticularly, the jaw 39 supported pivo*ably constitutes one arm of a lever 42, -the other arm of which supports a cam follower 43 which is permanently engaged with a fi,xed double cam 44 situated centrally in the i: drum 36. On rotation of the means of transport 35, the cam 44 will via the cam follower 43 and the lever 42 act upon the movable jaw so that i.t is moved between'a closed posi-tion, wherein the plane working surface o~ the jaw 39 ex-'I tends parallel in rela-tion to.the working surface (longer leg) of the fixed jaw 38, and an open posi-tion, wherein the mo.vable jaw 39 is pivoted out at an angle of substantially j 10'with the fixed jaw 38, which will be explained in more detail in the following description of the function of the machine.

Distributed around the means of transport 35 are a number of processing stations which are arranged at a ~ mutual pitch which corresponds to.the pitch between the ! holding devices 37 of the means of transport. As is evident mos-t clearly from Figure 1, a feeding-in station 45 is pre-sent at the end of the transportation unit 6 which is followed by a prefolding station 46 situated substantially abo~e the centre a~le of the means of transport 35. After the pre-folding station 4~ follo.ws an adhesive station 97, a final folding station 48, a stand-by station 49 not utilized at present and a feeding-out station 50. The different stations :' have been listed here in the sequence in which they are reached during the operation of the machine by an individual packing container moved by the means of transport 35. The means of transport 35 is thus indexed during operation step-by-step clockwise in Figure 1, each movement corresponding to.a turn which agrees with -the pitch angle between the dif-ferent stations (60').
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Beside the different processing stations each means of transport 35 i.s also surrounded by a number of guide rails (Fig. ~) which are fixed in relation to the foundation of the machine, and adapted to gui.de and process the packing containers moved by -the means of transport. Each means of transport 35 co-operates with two diffeent types of guide rails, namely on the one hand outer guide rails 51 which extend around -the means of transport subs-tan-tially at the same level as -the outer ends of the holding devices 37, and i.nner guide rails 5~ which extend around -the means of transport substantially at the same level as -the base sur-faces ~0 of the holding devices 37. The outer as well as the inner guide rails are doNble and are situated on ei.ther side of the means of transport 35, which i.s seen most clearly from Figure 2. The guide rails 51,52 are attached to.sides of a frame 53 situated outsi.de the means of transport 35 which in turn i.s rigidly jo.ined to.the founda-tion of the machine. The stand 53 is illustrated, for reasons of clarity, ; only by means of dash-dotted lines in Figure 2. The guide rails 51,5~ are thus fixed and therefore do.no:t follow the means of transport 35 duri.ng its indexing movemen-t.

The two.outer guide rails 51 commence a-t the same I level as the feeding-in station and ex-tend substantially from there past the preEold:ing station and further round the means of transport to finish at the feeding-ou-t station.
The distance between the two.guide rails 51 and the centre axle of the means of transport 35 varies inasmuch as -the yuide rails 51 at the same level as -the feeding-in station 45 are nearer to. the centre axle of the means of transport than they are during the remainder of their extension around the means of transport. More par-ticularly, the dis-tance between the guide rails 51 and the centre axle of the rneans of -transport is increased successively on the extension bet-ween the feeding-in station and -the prefolding station, to.
be diminished again -thereafter, so that the guide rails ., :
approach the periphery of the means of transport and run at substantially constant dis-tance during the remaining exten-sion of the guide rails to the feeding-out station. As a result, during the said First extension of the guide rai ls, the distance between the guide rails 51 andthe base sur-faces 40 of the holding devices ~7 will be increase~ succes-sively, seen in the direction of movement of the ho1ding device 37, from a distance which is less than the height of the holding device 37 to a distance which, at the same level as the pre-folding station 46, is greater than the height of the holding device 37.
Subsequently the guide rails 51 approach the height of the hold-ing device again and thereafter continue at this level right to the ~eeding-out station. The rnutual distance between the two guide rails also varies.
During the said first part of the extension of -the guide rails, -that is to say between the feeding-in station and the prefolding station, the distance between the guide rails 51 is slightly greater than the width of the holding device 37, that is to say the distance between -the laieral surfaces of the jaws 38,39 measured parallel with the centre axle of the means of transport 35. During the extension from the feeding-in s-tation to the prefolding sta-tion this distance is successively reduced, at the same time as the guide rails 51, as mentioned previously, move away more and more from the centre axle of the means of transport 35, and the mutual distance between the guide rails 51 has been reduced at the level of the prefolding station 46 so that the distance between the surfaces of the guide rails 51 facing each other largely agrees with the distance between the lateral surfaces of the jaws 38,39. During the continued e:~-tension of the guide rails 51 around the means of transport 35 -the dis-tance is successively reduce further so that at the level of the ad-hseive station 47 it is slightly smaller than the distance between the lateral surfaces of the jaws 38,39. This distance is retained substan-tially during the continued extension of the guide rails 51 up -to the feeding-out station.

The two inner guide rails 5? ex-tend similarly to the outer guide rails 51 around the means of transport 35 with the front end level with the feeding-in station 45, or between this and the prefolding station, and the rear end situated hefore the feeding-out station 50.
The -two inner guide rails 52, however, are placed appreciable closer to the centre axle of the means of transport 35 and are there~ore situated substantially level with the base surfaces 40 of the holding device 37.
The guide rails 52 extend along their whole length at a slight distance outside the lateral surfaces of the two jaws 38,39, that is to say the distance between the surfaces of the guide rails 52 facing towards each other is slig~tly greater than the width of the jaws 38,39. The width of the jaws 38,39, is in-tended, here as well as in other parts of the description and the claims, to mean the distance between the lateral surfaces of each jaw facing -from each otherg which distance substantially corresponds to -thewidth of a packing container handled. The height of a holding device is intended moreover to mean the distance frorn the base surface of the holding device facing towards a packing container to the outer end of the jaws 38,39. In other words the height of the holding device 37 substantially corresponds to the height of a processed packing container.

The front ends of the two gui de rai 1 s 52 are si tua-ted at -the feeding-in station at a distance from the centre axle of the means of transport which is slightly smaller than the distance be-tween the base surface 40 of the holding device and the said centre axle, that is to say the guide rails 52 are a little "below" the base surface 40 of the holding device. From the feeding-in station 45, thereafter, the di stance between the two gui de rai 1 s 52 and the centre axl e of the means of transport 35 i s successi vely i ncreased so that the gui de rai 1 s, at the 1 evel of the prefol di ng station 46 are at a slightly greater distance from the said centre axle than the base surface 40 of the holding device 37 . The two gui de rai 1 s 52 subsequently run at a smal 1 di s-tance "above" the base surface 40 during their remaining ex-tensi on up to the rear end.
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The outer gui de rai 1 s 51 as wel 1 as the i nner gui de rai ls 52 preferably consist of metal tube, through which a cooling medium e.g. water can be made to circulate during the opera-tion of the machine.

As mentioned earlier a number of fixed processing stations are provided around the means of transport 35 between which the packing containers are adapted to be moved during processing and forming interrnit-tently with the help of holding devices of the means of transport. During the rotation of the means of transport 35 the movable jaws 39 of the holding devices are acted upon through engagement of the cam followers 43 with the cam 44 between the open and closed position. In the open position the movable jaw is in a slightly pivoted-out position in relation to the fixed jaw which brings about the removal of a packing con-tainer to or from the respective holding device. In the closed posi-tion the two working surfaces o-f the jaws are substantially parallel and situated at such a distance from each other that they retain between themselves without difficulty a packing container placed into the holding device even when the holding device is upsidedowng that is to say a-t the lower part of the means oF transport 35 at the time. To make possible the said manoeuvring of the movable jc~ws 39 the cam 44 has a varying radius along its circumference.
More particularly the cam has during substantially one half turn a relatively small radius which increases there-af-ter to a maximum and subsequently is reduced again to the small radius mentioned earlier. The portion of the cam du-ing which the radius successively diminishes from the said maximum to the region with a smaller radius is located so that the holding devices 37 will be in an intermediate posi-tion that is to say they will be partially open when -they are in the prefolding station 46. The term "partially open"
is to be understood to mean that the holding device certainly retains the packing container between the jaws bu-t never-theless allows a certain movemen-t or correc-tion of the posi-tion of -the packing container in the holding device if -the packin~ container is subjected to external forces. I~or the rest the different portions of the cam are located so that during the in-termittent rotation of the means of transport the holding devices are open whilst they are at the feeding-in and feeding-out stations, and closed whilst they are at the adhesive and pressing shut stations. In the partially open position, wherein the holding device 37 is at the pre-folding station 46, the packing ~ontainer present in the holding device is certainly enclosed by the two jaws 38,39, i 10 but they do not retain the packing container immovably but the packing container can be moved, presenting a certain resistance, under the effect of external forces.

:` The feeding-in station 45 is situated at a level with the feeding-in device 33 which is supported by the -feed j assembly 30 and with the help of the same is movable to and !. fro between the feeding-in stations oF the two means oF
transport 35 so as to make possible the removal oF packing containers delivered from the transporta-tion unit 6 along a channel (no-t shown) extending transversely between the means of transport 35. At the feeding-in station a stop 54 mounted on the side of the frame 53 is also presen-t which is in the shape of a plate situated just in front of the feeding-in device 33 serving for the l.~nitation of the movement of 25 . the packing containers and so as to ensure that they end : up in correct position in the open holding device. The length of stroke of the feeding device 33 is such that the distance between the feeding-in device and the said stop 54 in the turning position of the feeding-in device corresponds to the width of a packing container, which ensures a correct placing and fixing of the packing container between the jaws of the holding device.

The prefolding station 46 comprises a base -Folding plate 55 arranged above the hold-ing device situated in the prefolding station and two top folding plates 56 arranged on either side of the holding device (Fig. 9). The base folding 1 ~1 7~

plate 55 as well as the top ~olding plates 56 are supported by a supporting arm 57 which is positioned so that it can freely rotate on a -transverse supporting axle 58 which extends parallel with the centre axle of the means of transport 35.
The base folding plate 55 and the top folding plates 56 are synchronously movable between an upper position and a lower position with the help of the cam 27 mounted on the upper axle 26 which rests against and acts upon a roller 59 sup-; ported so that it can rotate in the base folding plate 55 and which by means of a spring element (not shown) can be pressed against the surFace of the cam 27. The base folding plate 55 has a plane working surface Facing towards the holding device which in the upper, inactive position of the base folding plate is at a slight distance abo~e the outer (uppe~) end of the holding device so that during the action of the cam 27 in its active position it is substantially at the same level as the outer edge of the holding device 37, .
that is to say at the same level as the upper end faces o~
the two jaws 38,39. In other words, the base folding plate , 20 55 is movable in radial direction of the means of transport from its rest position outside the two guide rails 51 to its active position between the guide rails and the centre of the means of transport. The base folding plate 55 is bet-ween two and ten millimeters narrower than the Free distance between the guide rails 51 at the level of the prefolding station. This dimension is adapted to the thickness of the material of the packing container processed. The reci-procating movement of the base ~olding plate 55 caused by the cam 27 also imparts a corresponding movement to the two top folding plates 56 situated on either side oF the holding device, since these are joined to the supporting anm 57 by means of inter-mediate arms 60. I~he lower ends of the two-top folding plates 56, that is to say the ends facing towards the centre axle of-the means of trans-port 35 are thus moved between a rest position at a distance above-the base surEace 40 of the holding device 37 to an active position, sub-stantially at a level with the said base surface. The top foldiny plates 56 are adapted so as-to co-operate with-the inner guide rails 52, .; , serving as holders-up, which in the prefolding station are situated un either side of the holding device and are a small distance above the base surface 40. Between the feeding in station 45 and the prefolding station 46 there is a guide plate 61 which is suspended on the supporting arm 57 and is adapted so as to accompany it in its pivoting movement, when the carn 27 moves the base folding plate 55 between its upper and lower position. The guide plate 61 is situated a little outside the outer ends of the holding device 37 and is of a width which substantially corresponds to the width of the base folding plate 55.
., The adhesive station 47 in the embodirnent of the : machine in accordance with the invention is providecl with a hot-air assembly 62 which is fixed outside the path of move-ment of the means of transport 35. The hot-air assembly 62 is of a known type and produces hot air which via pipes and nozzles is supplied to the packing containers located in the adhesive station of the means of transport. More particularly, the hot air is supplied via two bottom nozzles 63 which are ', located at a slight distance outside the outer boundary sur-face of the holding device 37, so that they extend in under-neath the partially folded down bottom lugs of a packing con-tainer fixed in the holding device, and two top nozzles 64, located on either side of the .inner end of the holding device, which ex-tend in between -the side-walls of the pac~ing j container and the partially folded-in j top lugs of the packing container. The bottom nozzles 63 as well as the top nozzles 6~ are located outside the path of movement of the means of transport 35 and thus do not obstruct the rotation of the means of transport.

In a second embodiment of the machine ln accordance with the invention ~he hot-air assembly 62 and the hot-air nozzles 63,64 are replaced by a so-called hot-melc assembly, 7~
' . ~hat is to say an assembly for the supply of thermoplastic , adhesive to the packing container. The placing of the hot-; melt no~zles in th-is case substantially corresponds to the ; placing of the nozzles ~3,64, since the hot-melt, like the hot air, is to be applied between the corner lugs of the packing container and the packing container walls against which the corner lugs afterwards are to be folded down. The hot-melt assembly of this type is well known and is not described in any detail.
. 1 0 The final folding station 48 comprises a final folding assembly 65 (Figures 5 & 6) which is designed for the final folding or final shaping of the packing containers so that they obtain the desired parallelepipedic shape with folded-in and fixed corner lugs. The final folding assembly ! to this end comprises two lateral pressure devices 66 and a bottom pressure device 67 which are adapted so that in their active position, together with the two jaws 38,39 of the hold-ing device and the base 40 of the holding device, they form a practially closed parallelepipedic space whose inner dimen-sion agrees with the desired ultimate dimension of the pack-ing container. The two lateral pressure devices 66 comprise pressure plates 68 which have working surfaces facing each other. These working surfaces are wholly plane apart From l 25 the grooves 69 for the inner guide rails 52. Each one of the ;, pressure plates 68 is supported by a Front lever arm 70 to which the pressure plate is connected so that it is able to pivot by means of a connecting element 71. The connecting element 71 comprises rubber grommets and is flexible so that the pressure plate 68 endeavoul-s to assume a position sub-. stantially parallel with the lever 70. On contact with the sidewall of the packing container however each pressure plate 68 may pivot against the effect of the flexibility of the con-necting element 71 to lie flat against the said sidewall.

Each of the two front lever arms 70 is joined via i s~
an axle 72 supported in the machine frame to a rear leve~
arm 73 which is situated inside the transfer gearbox 15. The rear lever arms 73 are connected via a conventional system of links and a toggle joint construction 74 to a manoeuvring rod 75 which at its front end carries the bottom pressure device 67. The bo-ttom pressure device 67, which, like the lateral pressure devices 66, has a plane working surface facing towards the packing container, is thus adapted so as to be brought into contact against the packing container, . 10 syncrhonously with the lateral pressure devices, by means of one of the two operating arms 23 located in the transfer gearbox 15, which via the operating cams 22 are driven by the lower shaft 21 of the machine.

In order to prevent any damage to the final folding assembly 65 or the means of transport 35 if, for example, the movement is obstructed by foreign objects, a safety clutch 76 is incorporated in the driving system between the operating arm 23 and the final folding assembly 65 proper.
The safety clutch 76 is of the known type which automatically trips at a certain load, and does not need to be described in detail. The safety clutch 76 as wellas the rest of the driving mechanism for the final folding assembly 65 are loca-ted, as is evident especially from Figure S, in a bearing housing 77 mounted on the transfer gearbox 15. Outside the bearing housing are present therefore only the two lateral pressure devices 66 and the bottom pressure device 67 which are adapted so that during the operation of the machine they are moved between an open position or rest position, wherein the lateral pressure devices as well as the bottom pressure device are at such a distance from the means o-F
transport 35 that a holding device 37 canfreely pass between them, and an active position, wherein the lateral pressure devices and the bottom pressure device are pressed against a packing container present in the final folding position and fixed by a holding device 37.

7~

The next processing station for a packing container moved by means of the means of transport 35 is the stand-by station 49 which may be utilized for any desired further pro-cessing of the packing container, e.g the application of re-inforcing strips or bands, date stamping or the like.

The feeding-out station 50 is situated right in front of the feeding-out device 34 which is adapted so as to be moved synchronously with the feeding-in device 33 with the help of the reciprocating arms 31 of the feed assembly. The feeding-out device 34, like the feeding-in device 33, compri-ses pressure plates 78 which are adapted so as to remove the packing container from the holding device 37, the rnovable jaw 39 of which has been moved in the feeding-out station 1~ to its outwards pivoted position with the help of the cam 44.
ON oscillation of the feed assembly 30, the pressure plate 7~ removes one packing container at the time from the holding device 37 to a chute (not shown) situated alongside (outside) the holding device which is adapted so as to remove the pack-age to the conveyor 8 mentioned earlier, on which the packingcontainers, in upright position, are withdrawn from the machine in accordance with the invention.

When a machine in accordance with the invention is used together with a packing machine so as to form substan-tially parallelepipedic packing containers for liquid con-tents, the machine is placed as shown in Figure 1, that is to say adjoining a packing machine and connected to the same via the power transmission and driving unit 7. When the pack-ing machine proper is started, the machine in accordance withthe invention will also be started~ since it is driven with the help of the driving assembly o-f the packing machine. The packing containers or packing container blanks coming from the packing machine proper, which are wholly filled and closed, leave the packing machine, after they have been separated from the tube from which they have been manufactured, and are 7q~6 allowed to drop down onto the receiving conveyor belt lZ
which thanks to its angle with the horizontal plane checks the packing containers gently and transfers them to the main conveyor belt 10, on which they are fed at short mutual intervals in the direction of the final folding unit 5. When an individual packing conta-iner approaches the rear end of the main conveyor belt 10, the feed is taken over by the feeding-out conveyor belt 13 which is driven at substantially twice the speed compared with the main conveyor belt 10. The finger 14 of the feeding-out conveyor belt 13 will engage with the individual packing container and remove it from the rear end of the main conveyor belt 10 to the transverse feeding-in channel along which the feeding-in device 33 per-forms its reciprocating movement. The feeding-out conveyor belt 13 is synchronized with the movement oF the feeding-in device 33 in such a manner that it is always in one of its turning positions when a packing container is delivered to the channel. On removal of the feeding-in device 33 to its opposite end position the packing container fed-in is pushed via the channel to one or other of the holding devices 37 of the two means of transport 35 located at the feeding-in station, where the packing container is retained in the right position by the stop 5~.

The holding device 37 is dimensioned so that the packing container 2 placed into the holding device rests w;th its bottom surface against the base of the holding device at the same time as its projecting top and bottom corner lugs 79 and 8~ (the packing container is upside down in Figure 7) rest aainst the two inner guide rails 52 and one o~ the ou-ter guide rails 51. The movable jaw 39 is in its open position at a slight distance from the sidewall of the packing container, and the guide plate 61 is at a distance from the projecting sealing fin 81 of the packing container. Directly before the means of transport 35 is indexed again, the end of the guide plate 61, visible in Figure 7, will be lowered towards ' ~ ~'7~ ~ ~

the sealing fin 81, since the base -Folding plate 55 at the same time is restored to its rest position in the prefolding station.

When the guide plate 61 has been moved in the direc-tion towards the sealing fin ~1, the means o~ transport 35 is indexed (clockwise in Fig. 2) so that the packing cont-tainer 2 is !nade to glide along the guide rails 51,52 from the Eeeding-in station in the direction of the prefolding sta-10 . tion 46. Figure 8 illustrates the packing container and the holding device in an intermediate position between -these two stations, that is to say during the movement of the packing container -to the right in the Figure. The guide plate 61, by resting against the sealing fin 81, h~$ folded it down in the direction of the bottom surface 82 of the packing container.
As mentioned earlier, the packing container is not fixed immovably in the holding device until the same has passed the prefolding station, and in the position shown in Figure 8 the movable jaw 39 continues to be at a distance from the sidewall of the packing container, so that the packing con--tainer can be moved freely in the holding device and be steered by the guide rails 51,52. Since the latter in the region between the feeding-in station and the prefolding sta-tion successively increase their radius, the packing container 25 will be raised, owing to the engagement between the project-ing corner lugs and the guide rails, so that it ;s clear of the base 40 oF the holding device 37. At the same time the sealing fins ~1 are folded backwards, seen in the direction of movement of the packing container, owing to the contact with the guide plate 61 and the two inner guide rails 52.

When the indexing movement of the means of trans-port 35 ceases, the packing container is in the prefolding station 46. In this station the rnovable jaw 39 partially has come to rest against the side of the packing container 2, but the packing container is not wholly fixed and may continue .... , ... . ~

i7~S~;, ; to be moved in the holding device 37 (Fig. 9). Owing to the engagement between the guide rails and the corner lugs of the packing container7 the packing container is in an upper or outer position wherein its bottom sur~ace 82 is situated directly underneath the working surface of the base folding plate 55 f`acing towards the packing container which is in rest position. The upper shaft 26 is now made to rotate one turn by the indexing gear 17, when the cams 27 move the base folding plate 55 as well as the top Fo`lding plate 56 in the direction of the centre shaft of the means of transport 35 and back again. This motion moves the packing container down-wards until its bottom surface rests against the base 40 of the holding device 37 and the packing container once more is in the position into which it has been placed in the holding device during the feeding-in stage. Since the guide rails ; 51,52 in the prefolding station are at a greater distance from the centre axle of the mea~s of transport 35 then they were in the feeding-in station 45, the corner lugs 79,80 of the packing container will be folded upwards during this movement, that is to say in the direction away from the centre axle of the means of transport 35. The top lugs 79, which are situated at the base surface 40 of the holding device, are folded around the outer ends of the top folding plates 56 so that they form an angle of substantially q5 with the lateral surface of the packing container. The two bottom corner lugs 80 are folded more strongly and, aFter the move-ment has been completed, extend vertically upwards, that is to say at an angle of 90 with the bottom surface oF the packiny container. The folding of the two bottom corner lugs 80 has to take place with simultaneous compression of the material layers in the corner lugs, since ultimately these are to be folded down aga-inst and be attached to the bottom surface 82 of the packing container, over which passes the sealing fin 81. This great number of material layers, which have to be folded and pressed together beFore the corner lugs have been attached in the correct manner to the ' 7~3~6 bottom surface 82, make it imperative that during this pre-folding of the corner lugs they are compressed, and espe-cially the parts of the sealing fin 81 passing over them bet-ween the sides of the base folding plate 55 and the two outer guide rails 51. This can be done by ensuring that the free distance on either side of the base pressure plate is as small as possible, beariny in mind ~e thickness of the material, and preferably represents a value which corresponds to the theoretical material thickness in the corner lugs (usually between 1 and 5 mm). After the base folding plate 55 as wellas the top folding plates 56 have reverted to their outer rest position, the means of transport 35 is in-dexed once rnore ~l/6th turn clockwise), which brings the packin~ conta;ner from the prefoldin~ station to the adhesive station 47. During this removal the holding device 37 is closed, in that the movable jaw 39 is moved to a position parallel with the fixed jaw 38 so that the packing container is held immovably in the holding device. Since the distance between the two outer guide rails 51 is slightly reduced in the region be~ween the prefolding station and the adhesive station, the two bottom lugs 80 will be folded a little further towards each other so that when the packing container reaches the adhesive station 47 they form an angle of approx.
45 with the bottom surface 82.
When the holding device 37 stops in the adhesive station the packing container 2 is in such a position that the bottom nozzle 63 of the hot-air assembly is in the space between the partially folded down bottom corner lugs 80 and the bottom surface 82 of the packing container (Figure 10).
At the same time the top nozzles 64 of the hot-air assembly 62 are on either side of the upper end of the packing con-tainer facing towards the base 40 of the holding device and, more particularly, between the partially folded-in top corner lugs 79 and the free lateral surfaces of the packing container.
With the help of discharges holes of the nozzles 63,64, '7~5~

directed towards the corner lugs as well as against the pack-ing container walls, hot air is now blown against the surface of the packing container material in the region ~nderneath the corner lugs which is to be made use of for the attach- -ment of -the corner lugs to the underlying packing container wall. As a result the thermoplastic layer on the packing container is heated to such an extent that is melts and can serve as an adhesive for the attachment of the corner lugs.
After heating to the softening temperature of the thermo-plastic material, the packing container is removed by themeans of transport 35 until it is in the final folding station 48. During this removai the mutual position of the ~ui~è rails 51,52 is again slightly altered so that when the packing con-tainer approaches the final folding station the corner lugs form an angle with the underlying surface which is less than 45. In this manner unnecessary cooling of the heated surfaces during the removal of the packing container to the final folding station is prevented.

During the removal oF the packing container to the final folding station 48 the lateral pressure device 66 and .
the bottom pressure device 67 of the final folding assembly 65 are clear of the path oF movement oF the holding device so as not to engage in an obstructing manner with the pro- .
jecting corner lugs 79,~0 of the.packing container. After the packing container has been placed in correct position in the fin~l Folding station by the holding device .37, the lateral pressure device as well as the bottom pressure device are successively made to lie against the sidewalls 30. and the bottom respectively of the packing container. The pressure plates 68 of the lateral pressure device 66, as long as they are not acted upon by external forces, are oriented so in relation to the lever arms 70, that they are first made to lie against the sidewalls of the packing con-tainer at their ends situated towards the bottom of thepacking container, whereupon, on continued pivoting oF the ~'7~

lever arms t~ thelr ac-tive position, they are successively swung around the connecting element 71 ulltil they are parallel with each other and rest a~ainst the ~ree 5 sidewalls of the packing containers. Through "oblique positioning" of the pressure plates ~8 in rest position the length of stroke of the lever arms can be minimized, since the ends of the pressure plates situated at the top lugs are given in rest position a relatively greater distance to the packing container, so that -the corner lugs 79 can be accommo-dated without difficulty. The relative position of the two pressure plates 68 and the bottom pressure device 67 is illus-trated in Figure 11, where the position of the pressure plates 6~ at the instant when they first make contact with the lateral surface of the packing container is illustrated by means of dash-dotted lines. Thanks to this flexible sus-pension of the pressure plates 68, they will automatically adopt the correct position in relation to the lateral sur-faces of the packing container, so that any risk of damage or deformation of the packing container is appreciably reduced. When the lateral pressure device as well as the bottom pressure device have been brought into correct position they form together with the jaws and base of the holding device a substantially closed parallelepipedic space, whose ;:
inside dimensions correspond to the desired dimensions of the finished packing container. The packing container is allowed to remain in this position until the thermoplastic layer has solidified again and the sealing has been co~pleted.

The packing container is then removed through a renewed turniny of the means of transport 35 by 1/6th turn to the stand-by station 49, not utilized in this embodiment, which may be used, for example, for the application of re-inforcing cardboard discs on one or more of the free sur- `
faces of the packing container (Figure 12). Renewed turning `
of the means of transport 35 conveys the holding device 37 '7~56 with the packing container concerned to the feeding-out sta-tion 50. During the turning from the stand-by station 49 the cam follower 43 of the movable jaw 39 gradually runs out into the portion of the cam 44 where the radius is greatest, that is to say where the holding device is opened. In spite of this, however~ the packing container is retained in its position in the holding device with the help e~pecially of the two outer guide rails 51 against which the bottom of the packing container slides during the removal to the feeding-out station.

In the feeding-out station (Figure 13) the pressure plates 78 of the reciprocating feeding-out device 34 are moved in between the two jaws 38~39 of the holding device and push the unfastened packing container in lateral direc-tion out of the holding device 37 up to the sliding surface (not shown) arranged outside the means of transport 35 along which the packing container slides down to the conveyor 8.
Finished packing containers are thus fed-out alternately from the two means of transport 35 of the final folding unit 5 and transferred to the conveyor so as to be transported away~

As mentioned before, an alternative embodiment of the machine in accordance with the invention is provided with an assembly for the application of adhesive in place of the hot-air assembly 62 shown in the Figure. This variant is applicable even if the machine in accordance with the inven-tion is used for the ~inal. shaping of packing containers made o-F a material which is not covered with an outer thermo-plastic layer. The attachment of the corner lugs to the sidewalls of the packing container is achieved in this case with the help of thermoplastic glue whi ch i s applied underneath the corner lugs before these are pressed against the walls of the packing container.
The embodiment of the machine in accordance with ~ '7~

the invention, comprising a rotating transport means which by an indexing movement moves the packing containers between the different processing stations, guarantees a safe removal of the packing containers between accurately fixed positions at each processing station, which wholly eliminates the risk of deformation of the packing containers because of faulty placing of the same in relation to the processing tools. Moreover, since all the co-operating movablei elements of the machine, that is to say the means o~ transport, the different process-ing stations, the feed assembly, etc. are driven from a commonsource of power and are mechanically connected with each other via the driving assembly, the synchronization between the different movements cannot be lost in norrnal operation.
Hence the machine can also operate at high speed without any risk of faulty processing which ensures high production capa-city. This is further enhanced through the utilization of double transport means which alternately process the incoming packiny containers.

, ;

.,

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLU-SIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A machine for the processing of packing con-tainers comprising a drivable means of transport for the moving of the packing containers between different processing stations, the means of transport comprising an intermittently rotatable drum which along its periphery is provided with holding devices for individual packing containers, said holding devices being arranged at a mutually uniform pitch which corresponds to the pitch between the processing sta-tions fixed around the means of transport, and adapted so that during rotation of the drum they are manoeuvred between an open and a closed position, wherein each holding device comprises a pair of jaws extending substantially radially in relation to the drum and being capable to be brought into a closed position in which the distance between these jaws corresponds with the respective size of the packing container to be interposed between them, and out of this closed position into an open or partially open position in which the packing container can be moved in a radial direction between said jaws by means of external forces, and wherein guide rails are situated at a distance from one another, extending along the path of movement of the holding device, which are adapted so that on rotation of the drum, in at least a prefolding station they cooperate with corner lugs of the packing con-tainers to be folded against container walls, external forces being made effective in the prefolding station by a folding plate which is movable substantially in the radial direction of the drum from a rest position outside radially outer guide rails to an effective or active position between the outer guide rails the jaws being adapted to be brought, in the pre-folding station, into the partially open position.

2. A machine in accordance with claim 1, in which one jaw of the pair of jaws is firmly connected to the peri-phery of the drum and the other jaw is pivotal about an axle extending parallel with the centre axle of the drum.

3. A machine in accordance with claim 2, in which the pivotal jaw constitutes one arm of a lever, the other arm of which is engaged with a radial cam.

4. A machine in accordance with claim 3, in which the cam is firmly connected to the frame of the machine and is located in the central part of the drum.

5. A machine in accordance with claim 3 or 4, in which the cam is of such shape that the holding devices are open whilst they are at a feeding-in station and at a feeding-out station and closed whilst they are at an adhesive sta-tion and at a final folding station and partly open at the prefolding station.

6. A machine in accordance with claim 1, 2 or 3, in which two outer guide rails extend substantially from the feeding-in station and past the prefolding station, the distance between the guide rails and the base surfaces of the holding devices being increased successively, seen in the direction of movement of the holding device, from a dis-tance which is smaller than the height of the holding device to a distance which at a level with the prefolding station is greater than the height of the holding device.

7. A machine in accordance with claim 1, 2 or 3, in which the free distance between the sides of the base folding plate and the outer guide rails substantially corres-ponds to the theoretical material thickness of the corner lugs.

8. A machine in accordance with claim 1, in which at the prefolding station, two inner guide rails serving as holders-up are arranged radially inwards from the outer guide rails on either side of the holding device and at a small distance above the base surface of the same when the holding device is in the prefolding station.

9. A machine in accordance with claim 8, in which the inner and outer guide rails, respectively, are adapted so as to cooperate with and fold in top lugs or bottom lugs of a packing container when the packing container is moved by the base folding plate from an upper position to a lower position.

10. A machine in accordance with claim 1, 2 or 3, in which the base folding plate is supported by a supporting arm which is positioned so that it can freely rotate on a transverse supporting axle extending parallel with the centre axle of the drum.

11. A machine in accordance with claim 1, 2 or 3, in which two top folding plates are arranged on either side of the holding device and are synchronously movable with the base folding plate.