Packaging

Abstract

 Flat. carton sleeves 2 are fed to a multi-headed sleeve-opening turret 3, and thence to a multi-headed top closure pre-breaking turret 6 and a continuously advancing chain conveyor 5 around the turret 6. The conveyor 5 carries the sleeves 2 over a bottom closure pre-breaker 8, past a bottom closure heater 10 and through bottom closure sealing nip rollers 12 to a third multi-headed turret 13 on which bottom closure sealing and carton filling are performed. Thence, the cartons are fed by the conveyor 5 below a top closure tucking-in wheel 14, a top closure heater 16 and a top sealer 17 to a transverse transfer conveyor 20 which transfers the cartons 2 to a second transverse conveyor 24 which feeds the cartons over a bottom closure flaps heater 28 and a bottom closure flaps tucking-in device 29.

Description

[0001] This invention relates to packaging, particularly to the packaging of liquid, for example milk or orange juice, in cartons.

[0002] It is well known to form carton blanks from paperboard coated on both faces with thermoplastics and to fold and heat-seal the blanks into sleeves. Such sleeves are subsequently supplied in a flat form to a liquid-packaging machine which opens the flat sleeves, folds-in and heat-seals bottom closure sub-panels of the sleeves, fills with liquid the open-topped cartons so produced, and folds-in and heat-seals top closure sub-panels of the cartons. Conventionally, the sleeves and cartons on the machine are indexed, that is to say advanced stepwise, from one operational station to another, but it is more desirable for them to advance continuously, particularly from the point of view of providing a relatively high-speed, and therefore high-output machine. Yet the known designs of carton and of certain machine parts do not lend themselves to such continuous advance.

[0003] United States Patent Specification 3239995 discloses a machine for forming, filling, closing and sealing plastics-coated paperboard cartons in which flat sleeves are successively drawn from a magazine, erected into open-ended tubular form and loaded on to mandrels of a multi-station, indexing, bottom-forming, rotary turret. From the turret, the bottom-closed cartons are conveyed successively along a tubular trackway and then carried by an indexing chain conveyor to top-breaking, filling, top-heating, top-closing and top-sealing stations and then discharged from the machine. The sleeves and cartons are thus indexed through the machine.

[0004] United States Patent Specification 3280531 discloses a somewhat similar machine in which the opened sleeves are indexed along a stationary supporting track by a lifting comb-like structure positioned laterally of the track and having its teeth defining cells receiving the respective sleeves. At a first station, a mandrel is inserted into the sleeve, the top and bottom closure sub-panels are folded-in about horizontal edges of the mandrel and then the mandrel is removed. At a second station, a fin of the bottom closure is heated and, at a third station, the fin is pressure-sealed. At a fourth station, the projecting bottom fin enters a slot of a slidable track component which executes a short movement laterally of the stationary track to displace the fin flatly and in the meantime a press ram enters the open top of the carton and flattens the bottom closure. The carton then proceeds to filling, top-folding, top-heating and top-sealing stations.

[0005] British Patent Specification 1541910 discloses an apparatus for breaking-in, or-out, or both, end sub-panels of a gable top closure of a carton and including two forked breaking elements arranged to embrace from above the respective top edges of the end sealing sub-panels. Insertable into the top of the carton is a disc-like former of a ram, and two opposed stationary guides are located at the outside of the top of the carton. The breaking elements fold the top closure end sub-panels about edges of the former and the guides; both sub-panels are folded inwards about the ram, or both are folded outwards about the respective guides, or one sub-panel is folded inwards about the ram and the other folded outwards about one of the guides. Since the breaking elements perform somewhat reciprocatory motion, they are unsuitable for high-speed operation. Moreover, since the guides extend over only a very small part of the height of the carton, they oppose distortion of the carton over only a very small proportion of its height; in particular, they do not oppose distortion of the carton at its lower end during breaking and folding at that end.

[0006] United States Patent Specification 4,160,406 discloses a compact high speed carton opening and sealing machine and method employing a horizontal flat sleeve feeding mechanism. Sleeves are fed into the opening station, positioned against a stop and vacuum opened from the trailing side panel. The opened horizontal sleeve is maintained in a squared position and driven through the machine by flights mounted on parallel chain conveyors adjustably positioned adjacent the long sides of the sleeve. As the sleeve is driven through the machine, the trailing and leading bottom end flaps are sequentially folded into place and then the bottom side flaps are partially folded into place. With the side flaps in a partially folded position, adhesive is applied to either or both the bottom end flaps and the bottom side flaps. The partially folded side flaps are then maintained in position by a fixed anvil as the carton is delivered by the conveyor to a set of squaring stops. A transversely moving platen then moves the carton laterally to clear the end stops while bringing the end and side flaps into sealing relationship under time and pressure conditions sufficient to effect adhesion between the side and end flaps. Thereafter, the sealed carton is ejected from the machine by the movement of the succeeding carton into the sealing station. The vacuum opening of the sleeve is performed by two vacuum cups applied to the lower side panel of the sleeve and to the trailing side panel, respectively, the cup applied to the latter panel being turned, relative to the other cup, about an axis parallel to but spaced inwards from the natural axis of turning of the trailing side panel relative to the lower side panel. This has the disadvantage of risking distortion of the sleeve, or slipping of the turning vacuum cup relative to the trailing side panel.

[0007] According to one aspect of the present invention, there is provided a method of opening a sleeve of polygonal cross-section, comprising applying first and second suction members to respective first and second walls of the sleeve and causing the first and second walls to adhere to said members by suction, and moving the first suction member relative to the second suction member along a path to open said sleeve, characterized in that said path corresponds to a natural path of movement of the first wall relative to the second wall.

[0008] According to a second aspect of the present invention, there is provided apparatus for opening a sleeve of polygonal cross-section, comprising first and second suction members applicable to respective first and second walls of the sleeve, suction-producing means arranged to produce suction in said members to cause the first and second walls to adhere to said members by suction, means mounting the first suction member for movement relative to the second suction member along a path to open said sleeve, and drive means arranged to drive said first suction member along said path, characterized in that said path corresponds to a natural path of movement of the first wall relative to the second wall

[0009] Moving of the first suction member relative to the second suction member along a natural path of movement of the first wall relative to the second wall reduces any risk of distortion of the sleeve or slipping of the suction members on the walls.

[0010] According to a third aspect of the present invention, there is provided a method of producing a container containing a substance, including bringing bottom parts of said container together, and sealing said bottom parts together to form a bottom closure of said container, characterized in that substantially simultaneously with said sealing, said substance is filled into said container.

[0011] According to a fourth aspect of the present invention, there is provided apparatus for use in producing a container containing a substance, including means for bringing bottom parts of said container together and sealing said bottom parts together to form a bottom closure of said container, and filling means arranged to fill said substance into said container, characterized in that said filling means is arranged to fill said substance into said container substantially simultaneously with said sealing.

[0012] Filling of the container substantially simultaneously with the bottom sealing has the advantage of permitting reduction of the total time taken for any one container to undergo the packaging process.

[0013] According to a fifth aspect of the present invention, there is provided a method of conveying articles comprising advancing said articles to a transfer location in respective pockets of a first conveyor closely receiving said articles but each open at one lateral side of the path of said articles, and operating a second conveyor transversely of the first conveyor to strip the articles from the respective pockets in the sense of said one lateral side, characterized in that the first and second conveyors continuously advance and the articles slide transversely of the second conveyor while being stripped from the pockets.

[0014] According to a sixth aspect of the present invention, there is provided apparatus for conveying articles, comprising a first conveyor arranged to advance articles to a transfer location in respective pockets of said conveyor closely receiving said articles but each open at one lateral side of the path of said articles, and a second conveyor arranged transversely of said first conveyor to strip the articles from the respective pockets in the sense of said one lateral side, characterized in that the first and second conveyors are arranged to advance continuously and the second conveyor is such that the articles being advanced thereby can slide transversely thereof.

[0015] In this way, the articles move continuously through the apparatus.

[0016] According to a seventh aspect of the present invention, there is provided a method of producing a carton containing a substance, including causing said carton to be closely constrained externally by wall means at respective opposite sides of the carton, and breaking end closure sub-panels of said carton at said respective opposite sides by turning said sub-panels outwardly about said wall means, characterized in that said breaking is performed by a continuous-motion breaking device.

[0017] According to an eighth aspect of the present invention, there is provided apparatus for use in producing a carton containing a substance, comprising wall means for closely constraining said carton externally at respective opposite sides thereof, and breaking means for turning end closure sub-panels of said carton at said respective opposite sides outwardly about said wall means to break said sub-panels, characterized in that said breaking means is a continuous-motion breaking means.

[0018] The use of continuous-motion breaking means has the advantage of facilitating high-speed breaking. The external wall means advantageously extends over a considerable part of the length of the carton during breaking, preferably over the whole length of the main sub-panels of the carton, i.e. the whole spacing between the top closure and the bottom closure, in order to increase the opposition to distortion of the carton.

[0019] According to a ninth aspect of the present invention, there is provided a carton comprising first, second, third and fourth panels arranged in a loop around said carton, lines of weakness extending around said carton and thereby dividing said panels into loops of sub-panels including a loop of first, second, third and fourth top closure sealing sub-panels forming a sealing fin of a top closure, a loop of first, second, third and fourth top closure obturating sub-panels adjacent the row of sealing sub-panels, a loop of first, second, third and fourth bottom closure sealing sub-panels forming a sealing fin of a bottom closure, and a loop of first, second, third and fourth bottom closure obturating sub-panels adjacent the loop of bottom closure sealing sub-panels, further lines of weakness dividing the first and third bottom closure obturating sub-panels into substantially triangular sub-sub-panels, characterized in that the top closure is a gable top closure, the bottom closure is a flat bottom closure, and the said triangular sub-sub-panels lie at the outside of the second and fourth flat bottom closure obturating sub-panels.

[0020] This carton is particularly suitable for continuous advance in high-speed packaging.

[0021] In order that the invention may be clearly understood and readily carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:-

Figure 1 shows a diagrammatic top plan view of a packaging machine for producing cartons filled with liquid,

Figure 2 shows a diagrammatic fragmentary side elevation of the machine,

Figure 3 shows a detail of Figure 1, in particular of a feeder for flat, carton sleeves,

Figure 4 shows a section taken on the line IV-IV of Figure 3,

Figure 5 shows another detail of Figure 1, in this case of part of a carton sleeve opening turret,

Figure 6 shows a section taken on the lines VI-VI of Figure 5,

Figure 7 shows a detail of Figure 2, in this case of a top pre-breaker turret,

Figure 8 shows a fragmentary top plan view of the top pre-breaker turret,

Figure 9 shows a fragmentary elevation taken in the direction of the arrow IX in Figure 7,

Figure 10 shows another detail of Figure 2, and

Figure 11 shows a plan view of a carton blank from which a flat carton sleeve is to be formed.

[0022] Referring to the drawings, particularly to Figures 1 and 2, the packaging machine is designed for high-speed packaging of liquid, for example milk or orange juice, in gable-topped cartons. It can attain a speed of at least 300 cartons per minute. It includes a feeder 1 for feeding flat carton sleeves 2 to a rotary sleeve-opening turret 3, which feeds the sleeves into chain pockets 4 of a continuously advancing endless conveyor chain 5 as the chain 5 passes around a rotary top pre-breaker turret 6. Each sleeve 2 has been made from a blank (shown in Figure 11) consisting of paperboard coated on both faces with a suitable thermoplastics. The pockets 4 are so designed that they closely receive the sleeves 2 with the sleeves in a fully opened, rectangular condition, the three upright walls of the pockets, and a fixed vertical guide wall along which the open side of each pocket 4 moves, substantially preventing movement of the sleeve relative to the pocket in any horizontal direction. A rotary horizontal supporting plate 7 of the turret 6 prevents the sleeves 2 from falling out of the pockets 4. The chain 5 advances the sleeves 2 along a fixed horizontal supporting plate 7¹ to over a bottom pre-breaker 8, by which bottom closure sub-panels of each carton are pre-broken along score lines, the walls of the pocket 4 and the vertical guide wall acting effectively as an encircling mandrel for maintaining the general rectangular shape of the remainder of the sleeve during this bottom pre-breaking. The chain 5 forwards the sleeves 2 from the pre-breaker 8 to a pair of bottom closure ploughing-in
and guide rails 9, which force towards each other lateral sub-panels of the bottom closure and which guide them in a partially open condition over a bottom heater 10 which blows hot air upwards into the bottom closure, so rendering tacky the internal thermoplastics coating thereof, The chain 5 advances the sleeves 2 along the rails 9, which at their farther ends plough-in the lateral bottom closure sub-panels to a condition in which lateral sealing sub-panels thereof are virtually in contact with each other, whereupon the chain 5 forwards each sleeve 2 to a lead-in block 11 which is vertically slotted to receive the bottom sealing sub-panels and lead them into a pair of pre-sealing nip rollers 12. The chain 5 advances the carton 2' so formed to a rotary filling and bottom-sealing turret 13, in which the bottom closure sealing sub-panels are held together for a relatively long time to give good sealing, and the liquid is filled into the carton which, since the liquid is cool, also assists sealing. A carton being bottom-sealed in indicated at 2' in Figure 1 from which it will be noted that triangular parts of the bottom closure thereof project below the walls of the pocket 4. The chain 5 passes around this turret and forwards the filled cartons to a top tucker 14, from which the chain carries the cartons along between a pair of top closure ploughing-in and guide rails 15, above which is a top heater 16 which blows hot air downwards onto top closure sub-panels of the carton to render tacky the thermoplastics coatings thereof. The chain 5 advances the cartons from the top heater 16 to a top sealer 17 consisting of a pair of horizontal endless chains 18 each provided with a series of horizontal sealing jaws 19. The jaws 19 of the two chains 18 come together in pairs to grip between them gable top closure sealing sub-panels of the carton to form the gable top closure sealing fin. The chain 5 advances the sealed cartons to a transfer location at which a continuously advancing conveyor 20 strips the sealed cartons from the continuously advancing chain 5. The conveyor 20 consists of two endless chains 21 and 22 arranged parallely to each other and each moving along an endless path arranged in a vertical plane, the chain 21 being arranged above the chain 5 and the chain 22 being arranged below the same. Each of the chains 21 and 22 includes slats 23 extending parallely to the conveyor 5, the lower run of the chain 21 and the upper run of the chain 22 moving in the same direction as each other, namely horizontally perpendicularly outwards of the return run of the chain 5. The slats 23 of the lower run of the chain 21 and the slats 23 of the upper run of the chain 22 come to bear against the respective top and bottom fins of the cartons 2' arriving at the transfer station and thereby push laterally outwards the cartons in the respective chain pockets 4, although the chain 5 continues to push the cartons towards the turret 6, which it can do because the slats 23 allow sliding of the cartons transversely of the conveyor 20. The conveyor 20, which is relatively short, moves at the same speed as a second transverse conveyor 24, which again consists of a pair of upper and lower endless chains 25 and 26 provided with slats 27. The action of the chain 5 causes the cartons to slide from between their respective pairs of slats 23 to between their respective pairs of slats 27, by which they are displaced to a second bottom heater 28 which renders tacky the thermoplastics coating of the downwardly directed outside faces of the sub-panels of the bottom closure, and thence to a tucking-in device 29 for tucking inwards triangular end flaps of the bottom closure and retaining those flaps in a tucked-in condition whilst they seal against underneath surface portions of the bottom closure. Referring to Figure 3, the feeder 1 includes horizontal guide rails 30 for the flat sleeves 2, a pack of flat sleeves 2 (not shown) being advanced stepwise by pressing fingers 31 mounted on respective slide blocks 32 themselves guided on respective guide rods 33. The blocks 32 are advanced stepwise in synchronism by respective drive chains 34. At the exit from the guide rails 3(1, the sleeves 2 are supported by a horizontal rail 35 and are there stripped one-by-one from the end of the pack by a lug (not shown) provided on a horizontal endless conveying chain 36. The lug pushes the stripped sleeve into a nip between a driven roller 37 and an idler roller 38. The rollers 37 and 38 advance the sleeve into a position in which it is face-to-face with one of eight identical suction pads 39 (see Figures 5 and 6), against which the sleeve is pressed by a pressing-on roller device 40 shown in more detail in Figure 4. The device 40 includes a vertical shaft 41 to the upper end of which is fixed a radial arm 42 which at its forked outer end is provided with a double roller arrangement 43 which is embraced by the forked outer end of the arm 42 and which is guided for movement in the fork by means of a horizontal stud 44 fixed thereto. The roller arrangement 43 is urged outwardly by a helical compression spring 45 encircling the stud 44 and is limited as to its outward movement by nuts 4C on the stud 44. With the sleeve 2 in position against the suction pad 39, the shaft 41 swings the roller arrangement 43 to a position in which it presses the sleeve 2 against the suction pad 39 and at the same time causes the sleeve 2 to depress and thus open a valve closure member 47 of a valve 48 of the pad 39.

[0023] Referring to Figures 5 and 6 the sleeve opening turret 6 comprises a fixed, vertical central axle 50 to the upper end of which is keyed a horizontal cam plate 51 formed with a continuous camming slot 52. Vertically through the centre of the axle 50 extends a vacuum line 53 which terminates at its upper end in a distributor valve 54, a rotary upper part 55 of which is connected via respective suction tubes 56 to the suction pads 39. Mounted for rotation about the axle 50 is a co-axial tubular body 57 which is driven at a toothed ring 68 and to which the rotary part 55 is attached by a strap 58. The body 57 has the suction pads 39 distributed around the wider, upper part thereof. Arranged on the body 57 adjacent to the respective pads 39 are eight cranked suction brackets 59 each provided with three small suction pads 60. Each pad 60 is similar toeach pad 39 in incorporating a valve openable by depression of its valve closure member by contact with a flat sleeve 2. Each bracket 59 is swingable about a vertical axis in vertical bearings 61 mounted in respective horizontal flanges 69 of the wider upper part of the body 57. Just below the lower bearing 61, each bracket 59 has fixed thereto a pinion 62 of a rack-and-pinion device 62, 63 of which the rack 63 is fixed to a slide bar 64 guided in the body 57 and mounting at its inner end a roller follower 65 which runs in the slot 52. Each tube 56 has a branch duct 66 therefrom leading via a connector 67 to the upper end of the bracket 59, most of which is hollow so that suction can be applied to the pads 60.

[0024] In operation of the sleeve-opening turret 3, the continuously rotating turret brings the sleeve 2 from a position shown at a in Figure 1, in which one of two adjacent panels of the flat sleeve are held by suctio:. against one of the suction pads 39, through a position b in which the adjacent bracket 59 has been swung to bring its suction pads 60 against the other of those two panels and in which that other panel is held against the pads 60 by suction, through a position c in which the bracket 59 has been swung about its axis of turning, which coincides with the junction line between those two panels, partially to open the sleeve to a cross-section of diamond shape as shown, (since the axis of turning of the bracket 59 coincides with the junction line, the pads 60 of the bracket 59 move along an arcuate path corresponding to the natural path of movement of that other panel relative to that one panel), through a position d, in which the bracket 59 has continued to turn and brought the sleeve to a condition in which its cross-section is rectangular, and through a position e in which the bracket 59 has continued to turn in order partially to close the sleeve to bring it again to a condition in which its cross-section is of a diamond shape, to a position f in which the sleeve is again of a rectangular cross-section, as at d, and is closely received in a chain pocket 4, the bracket 59 having turned back to its angular position shown at d, the gradual change in shape of the sleeve cross-section from e to f enabling the sleeve to be fitted closely into the pocket 4 with substantially no distortion of the sleeve, because the linear speed of the suction cups 39 and 60 holding the sleeves 2 is made to he higher than that of the chain pockets 4.

[0025] Referring to Figures 7 to 9, the top pre-breaker turret 6 comprises a plurality of top pre-breakers 70 equi-angularly spaced around the turret 6 and arranged to coincide in vertical alignment with the chain pockets 4 as these latter move around the turret 6. The turret comprises a fixed vertical central axle 71 on which is mounted a rotary body 72 carrying the pre-breakers 70. Encircling the axle 71 is a fixed sleeve 73 formed with a continuous external peripheral camming slot 74. In the slot 74 there runs a roller follower 75 attached to the lower end of a reciprocatory vertical rod 76 which is guided in linear bearings 77 in the body 72, Encircling the upper part of the rod 76 is a sleeve 78 in which the rod 76 is mounted by way of linear bearings 79. A helical compression spring 80 acts between an annular washer 81 supported by an upwardly facing internal shoulder of the sleeve 78 and a flanged bush 82 encircling and retained on the upper end of the rod 76. The sleeve 78 is attached to a vertical slide 83 mounted in a vertical guide 84 forming part of the body 72. Also attached to the sleeve 78 is a radially outwardly projecting bracket 85 supporting, at respective lateral sides thereof, respective bearings 86 mounting respective cranked shafts 87 having respective pinions 88 fixed to the inner ends thereof. The pinions 88 mesh with respective vertical racks 89 fixed to respective opposite sides of the rod 76. The crank in each shaft 87 is located radially outwardly of its bearing 86 and, at its radially outer end each shaft 87 has fixed thereto a triangular flap 93 for pre-breaking top closure sub-panels of the sleeves 2. Between the outer ends oi the shafts 87 there is located an internal anvil consisting of a horizontal plate 90 with a downwardly tapering skin 91.

[0026] In operation, as each pre-breaker 70 moves around the axle 71 with the aligned pocket 4 containing a sleeve 2, its follower 75 lowers the rod 76 from its uppermost position shown in full lines in Figure 8 into its lowermost position 76' shown in dot-dash lines in that Figure. Near the end of this downward stroke of the rod 76, the sleeve 78 strikes a hardened abutment 92 on the body 72. This occurs when the topmost surface of the internal anvil 90, 91 has reached the level of the lowermost boundaries of the sub-panels of the gable top closure. The continued moving down of the rod 76, now relative to the sleeve 78 and against the action of the spring 80, causes the racks 89 to rotate the pinions 88 to bring the triangular flaps 93 from the full-line condition shown in Figure 9 for one of the flaps and one of the shafts 87 to the condition shown in dot-dash lines 87' and 93'in that Figure, thereby to pre-break the top closure sub-panels of the sleeve 2. Then the follower 75 lifts the rod 76 back into its uppermost position, so initially turning the flaps 93 and tht shafts 87 back into the upright full-line positions for the flaps 93 shown in Figure 9 and thereafter raising the sleeve 78 into its position shown in Figure 8, thereby lifting the anvil 90, 91 completely out of the sleeve 2.

[0027] The items 8, 9, 10 and 11 are shown in more detail in Figure 10. The pre-breaker 8 includes a pre-breaker wheel 95 which rotates continuously in the sense of the arrow A. The wheel 95 is in the form of a vertical plate formed with four trapezium-shaped lobes 96 equi-angularly spaced about the axis of the wheel. The wheel 95 is fixed to a rotary driving flange 97 by means of bolts 98 (of which only one is shown) passing through holes 99 in the wheel 95, which holes are arcuate in order to allow for an accurate pre-setting of the angular position of the wheel 95 relative to the flange 97. As each sleeve 2 arrives above the wheel 95, one of the lobes 9G enters the open bottom of the sleeve and the leading face of that lobe 96 displaces forwards the leading sub-panels of the bottom closure of the sleeve 2 and its lagging face displaces rearwards the lagging sub-panels of that bottom closure. While this is being done, the three walls of the relevant pocket 4, together with the fixed vertical guide wall closing the open side of the pocket 4, which wall is co-extensive with the pocket walls insofar as its vertical dimension is concerned, act as an external mandrel for this bottom pre-breaking, the bottoms of the walls for this purpose being arrraged at the level of the tops of obturating sub-panels of the bottom closure.

[0028] The bottom closure sub-panels are now immediately received between the rails 9 which are arranged at approximately the level of boundaries between sealing sub-panels, on the one hand, and the obturating sub-panels, on the other hand, of the bottom closure. These rails initially converge and thus they plough-in, in other words swing towards each other, the lateral sub-panels of the bottom closure whereby the leading and lagging sub-panels thereof are swung increasingly away from one another. As the rails 9 approach the heater 10, they begin to run parallely to each other, so that the ploughing-in effect ceases. The heater includes a heater box 100 extending along beneath the chain 5 and of a rectangular cross-section, as shown at 100', with a hot air outlet slot 101 formed centrally through the top wall thereof. Immediately above the slot 101 and effectively narrowing the mouth thereof is a pair of parallel guide rails 102 extending the length of the box 100. The guide rails 9 and 102 are each of a tubular form and are cooled by passing cooling liquid through their interiors. The arrangement is such that the lowermost extremities of the sleeve 2 slide along the guide rails 102 so that most of the hot air applied through the slot 101 to the bottom closure sub-panels is applied to the insides of those panels and renders tacky the thermoplastics coatings of those insides, particularly of the bottom closure sealing sub-panels, which are in fact nearest tu the slot 101. Hot air is supplied to the box 100 from a heater blower lC3 via a supply pipe 104 and a flap valve 105. The flap 106 of the valve 105 is movable by an operating ram 107 between its position shown in chain lines in Figure 10 in which the hot air flows into the box 100, and its position shown in dot-dash lines in Figure 10, in which the hot air is diverted to an exhaust pipe 108 and into which the flap 106 is moved automatically whenever the chain 5 is stopped, in order to avoid overheating of the sleeves 2. At their farther end, the rails 9 converge upwardly towards each other, as indicated at 9', and thereby force the bottom closure sub-panels further inwards towards each other. As the bottom closure sealing sub-panels leave the rails 9 they enter a converging portion 109 of the vertical slot in the block 11. The converging portion 109 merges into a parallel-sided portion 110, in which the sealing sub-panels are face-to-face with each other.

[0029] The filling and bottom-sealing turret 13 will now be described with reference tc Figures 1 and 2. The turret includes a plurality of reciprocatory bellows fillers 111 which rotate around the vertical axis of the turret in vertical alignment with the chain pockets 4 as these proceed around the turret. The fillers 111 are supplied with cool liquid, such as milk or orange juice, from a tank 112 rotating with them. Each filler 111 has there- above a pneumatic ram 113 for operating the same. Arranged vertically below the respective fillers 111 are respective bottom closure sealers 114. Each sealer 114 includes a pair of clamping jaws 115 and 116 of which the jaw 115 is fixed relative to the rotary body 117 of the turret 13, and of which the jaw 116 is movable radially of the turret 113 relative to the jaw 115 by means of a roller follower 118 running in an annular camming slot 119 in a camming plate 120 fixed relative to the frame of the machine. The chain 5 carries the bottom pre-sealed carton from the rollers 12 to between a pair of jaws 115 and 116 and these jaws clamp together the sealing sub-panels of the bottom closure over a considerable part of one revolution of the turret 13, the corresponding filler 111 meanwhile filling the carton with the cool liquid from the tank 112.. In the open condition, the jaws 115 and 116 are in the relative positions shown at 115 and 116 in Figure 1, but, in the closed condition, they are in the relative positions shown at 115' and 116' in Figure 1. The persistent clamping effect of the jaws and the cooling effect of the liquid give a very good sealing together of the inside thermoplastics coatings of the sealing sub-panels, so providing a good seal along the whole of the vertical fin of the bottom closure of the carton.

[0030] The chain 5 then carries the filled carton 2' to the top tucker 14 which includes a plate-form wheel 121 including four legs 122 terminating outwardly in a foot having a forwardly projecting toe 123 and a rearwardly projecting heel 124. The speed of turning of the wheel 121 relative to the speed of advance of the chain 5 is such that each filled carton 2' catches up with a heel 124 of one leg 122 and thus the leading sub-panels oi the top closure are pushed firmly in between the lateral sub-panels thereof,and then the toe 123 of the next leg 122 catches up with the carton and thus the lagging sub-panels of the carton are pushed firmly in between the lateral sub-panels thereof. The provision of the tucker 14 ensures that any leading or lagging sub-panels which have moved out of their desired positions between the lateral sub-panels since pre-breaking at the turret 6 are brought back into their desired positions. The top heater 16 will not be described in detail since it is similar to the bottom heater 10, including a heater box 125, a flap valve 126, a supply pipe 127, a heater blower 128, and an exhaust pipe 129.

[0031] Figure 11 shows a carton blank designed to produce a carton sleeve for use in the machine hereinbefore described with reference to Figures 1 to 10. The blank consists of paperboard coated on both faces with a suitable thermoplastics. By means of parallel score lines 130 it is divided into five panels 131 to 135, of which the panel 135 will be heat-and pressure-sealed to the panel 131 to provide a side seam of the carton sleeve 2. By means of score lines 136 to 139 perpendicular to the score lines 130, the panels 131 are divided to form five gable top closure obturating sub-panels 141 to 145, five gable top closure sealing sub-panels 151 to 155 outwardly thereof, five flat bottom closure obturating sub-panels 161 to 165, and five flat bottom closure sealing sub-panels 171 to 175 outwardly thereof. Each of the obturating sub-panels 141, 143, 161 and 163 is divided into triangular sub-sub-panels by score lines 146 extending respectively from those two corner regions of the sub-panels nearest to the centre of its panel 131 or 133 to the middle of that side of the sub-panel furthest from the centre of its panel. From the junction of each pair of score lines 146 there extends centrally across the adjacent sealing sub-panel 151, 153, 171 or 173 another score line 147 parallel to the score lines 130 to divide that sealing sub-panel into two rectangular sub-sub-panels. The sub-panel 145 is formed with an oblique score line 148 corresponding to one of the score lines 146 of the sub-panel 141. In the sealed carton 2' produced from the carton sleeve 2, the sub-panels-151 and 153, each in a condition folded upon itself about the score lines 147, together with the sub-panel 155, are sandwiched between the sub-panels 152 and 154 and form a sealing fin of the gable top closure. Moreover, each of the sub-panels 171 and 173 folded upon itself about its score line 147, but with the sub-panel 175 between the rectangular sub-sub-panels of the sub-panel 173, is sealed face-to-face upon itself, whilst the sub-panels 172 and 174 are sealed together face-to-face, thereby providing a sealing fin appreciably longer than the width of the widest of the panels 131 to 135, this latter sealing fin being turned back upon the sub-panels 161 to 164. The triangular flaps formed by the folded sub-panels 161 and 163 are turned underneath and the in parts 171 and 173 are sealed to the fin parts 172 or 174, thereby to form the flat bottom of the carton. If it is desired that the gable top closure should, in known manner, incorporate a pouring spout, the sub-panels 142 and 144 are formed with oblique score lines 149, to facilitate pulling out of the folded sub-panels 143 and 153 to provide the spout.

Claims

1. A method of opening a sleeve (2) of polygonal cross-section, comprising applying first and second suction members (60, 39) to respective first and second walls of the sleeve (2) and causing the first and second walls to adhere to said members (60, 39) by suction, and moving the first suction member (60) relative to the second suction member (39) along a path to open said sleeve (2), characterized in that said path corresponds to a natural path of movement of the first wall relative to the second wall.

2. A method according to claim 1, wherein said first and second walls are adjacent each other and interconnected by a fold line, said first and second walls are adhered to said members (60 ,39) by suction as aforesaid at such relative locations that said fold line coincides with an axis of turning of said first member

(60) relative to said second member (39), and said first member (60) is moved relative to said second member (39) as aforesaid by rotation of said first member (60) relative to said second member (39) about said axis.

3. Apparatus for opening a sleeve (2) of polygonal cross-section, comprising first and second suction members (60, 39) applicable to respective first and second walls of the sleeve (2), suction-producing means (53-56, 66, 67) arranged to produce suction in said members (60, 39) to cause the first and second walls to adhere to said members (60, 39) by suction, means (61) mounting the first suction member (60) for movement relative to the second suction member (39) along a path to open said sleeve (2), and drive means (62, 63) arranged to drive said first suction member (60) along said path, characterized in that said path corresponds to a natural path of movement of the first wall relative to the second wall.

4. Apparatus according to claim 3, wherein said means mounting the first suction member (60) for movement relative to the second suction member (39) comprises pivot means whereby said first suction member (60) is turnable about an axis relative to said second suction member (39), said apparatus further comprising means (37, 38, 43) arranged to dispose initially said sleeve (2) relative to the first and second suction members (60, 39) such that a fold line common to said first and second walls coincides with said axis.

5. A method of producing a container containing a substance, including bringing bottom parts (171-175) of said container together, and sealing said bottom parts. (171-175) together to form a bottom closure of said container, characterized in that substantially simultaneously with said sealing, said substance is filled into said container.

6. A method according to claim 5, and further comprising continuously advancing said container during said sealing and said filling.

7. A method according to claim 5 or 6, wherein said sealing comprises setting thermoplastics material of said bottom closure, and said substance cools said bottom closure during filling.

8. Apparatus for use in producing a container containing a substance, including means (9-12, 115, 116) for bringing bottom parts (171-175) of said container together and sealing said bottom parts (171-175) together to form a bottom closure of said container, and filling means (13, 111) arranged to fill said substance into said container, characterized in that said filling means (13, 111) is arranged to fill said substance into said container substantially simultaneously with said sealing.

9. Apparatus according to claim 8, and further comprising a rotary turret (13) carrying for rotation therewith a plurality of pairs of sealing jaws (115, 116) of said means (9-12, 115, 116) for bringing bottom parts (171-175) of said container together and sealing said bottom parts (171-175) together, and above the respective pairs of sealing jaws (115, 116), a plurality of filling nozzles (111) of said filling means (13, 111).

10. Apparatus according to claim 9, and further comprising a continuously advancing conveyor (5) including pockets (4) for respective cartons, said conveyor extending around said turret (13) above said pairs of sealing jaws (115, 116) , with said pairs of jaws (115, 116) being aligned with respective pockets (4) of said conveyor (5).

ll. A method of conveying articles comprising advancing said articles to a transfer location in respective pockets (4) of a first conveyor (5) closely receiving said articles but each open at one lateral side of the path of said articles, and operating a second conveyor (20) transversely of the first conveyor (5) to strip the articles from the respective pockets (4) in the sense of said one lateral side, characterized in that the first and second conveyors (5, 20) continuously advance and the articles slide transversely of the second conveyor (20) while being stripped from the pockets (4).

12. A method according to claim 11, and further comprising operating, transversely of the first conveyor

(5), a third continuously advancing conveyor (24) side-by-side with said second continuously advancing conveyor (20) to receive the articles from the second conveyor (20). ,

13. A method according to claim 11 or 12, wherein the stripping of the articles from the respective pockets (4) as aforesaid includes pushing each article at its top and at its bottom in said sense of said one lateral side.

14. Apparatus for conveying articles, comprising a first conveyor (5) arranged to advance articles to a transfer location in respective pockets (4) of said conveyor (5) closely receiving said articles but each open at one lateral side of the path of said articles, and a second conveyor (20) arranged transversely of said first conveyor (5) to strip the articles from the respective pockets (4) in the sense of said one lateral side, characterized in that the first and second conveyors (5, 20) are arranged to advance continuously and the second conveyor (20) is such that the articles being advanced thereby can slide transversely thereof.

15. Apparatus according to claim 14, and further comprising a third continuously advancing conveyor (24) arranged transversely of said first conveyor (5) and side-by-side with said second conveyor (20) to receive the articles from the second conveyor (20).

16. Apparatus according to claim 14 or 15, wherein said second conveyor (20), or each of the second and third conveyors (20, 24), comprises two conveying devices (21, 22, 25, 26) arranged respectively above and below said first conveyor (5) and transversely of said first conveyor (5).

17. Apparatus according to claim 16, wherein each of the two conveying devices (21, 22, 25, 26) comprises slats (23, 27) for pushing on respective ends of the articles.

18. A method of producing a carton (2) containing a substance, including causing said carton (2) to be closely constrained externally by wall means (5) at respective opposite sides of the carton (2), and breaking end closure sub-panels (161, 163, 171, 173) of said carton at said respective opposite sides by turning said sub-panels (161, 163, 171, 173) outwardly about said wall means, characterized in that said breaking is performed by a continuous-motion breaking device (8).

19. Apparatus for use in producing a carton (2) containing a substance, comprising wall means (5) for closely constraining said carton (2) externally at respective opposite sides thereof, and breaking means (8) for turning end closure sub-panels (161, 163, 171, 173) of said carton (2) at said respective opposite sides outwardly about said wall means (5) to break said sub-panels, (161, 163, 171, 173), characterized in that said breaking means (8) is a continuous-motion breaking means (8).

20. Apparatus according to claim 19, wherein said wall means (5) is of a length along the longitudinal axis of the carton (2) substantially equal to the spacing between respective end closures of the carton (2).

21. A carton comprising first, second, third and fourth panels (131-134) arranged in a loop around said carton (2), lines of weakness (136-139) extending around said carton (2) and thereby dividing said panels (131-134) into loops of sub-panels (141-144, 151-154, 161-164, 171-174) including a loop of first, second, third and fourth top closure sealing sub-panels (151-154) forming a sealing fin of a top closure, a loop of first, second, third and fourth top closure obturating sub-panels (141-144) adjacent the row of sealing sub-panels (151-154), a loop of first, second, third and fourth bottom closure sealing sub-panels (171-174) forming a sealing fin of a bottom closure, and a loop of first, second, third and fourth bottom closure obturating sub-panels (161-164) adjacent the loop of bottom closure sealing sub-panels (171-174), further lines of weakness (146) dividing the first and third bottom closure obturating sub-panels (161, 163) into substantially triangular sub-sub-panels, characterized in that the top closure is a gable top closure, the bottom closure is a flat bottom closure, and the said triangular sub-sub-panels lie at the outside of the second and fourth flat bottom closure obturating sub-panels (162, 164).

Drawing