IE42741B1 - Manufacture of containers comprising paperboard cartons with liquid-proof liners - Google Patents

Description

This invention relates to the manufacture of knocked down cartons of the type in which a paperboard blank is provided with a flexible tubular liner suitable for contail fluid materials.

Various prior proposals have been made for the provis of such cartons, but their acceptance has been limited due to problems in obtaining efficient manufacture, erection and sealing of such cartons on the high speed production lines which are an economic necessity in most areas of the packaging industry, as well as problems in dispensing their contents. We have developed carton designs for use in various different applications which substantially overcome the erection, sealing and dispensing problems referred to above, but these entail the use of knocked down cartons in which a flexible bag of appropriate dimensions often overlapping those of the paperboard blank must be placed accura on the latter, which must bear a relatively complex partem of adhesive treated areas. Known methods of producing lined knocked down cartons do not meet these requirements, and it is to this problem that the present invention is directed.

According to the invention, a method of making knocked down containers comprising paperboard cartons with flexible liquid-proof liners, comprising applying adhesive to success paperboard carton blanks having a plurality of adjacent side panels and a plurality of flaps at each end, successively feeding the blanks tangentially and endways on past a rotating delivery cylinder, feeding continuous laid-flat tubular flexible bag material around the periphery of the cylinder, forming said material while on the cylinder into successive separate tubular bags each having one open end and one closed end, by transverse cutting and heat sealing operations carried out on longitudinally adjacent portions of the material, holding the bags against the surface of the cylinder while it rotates to apply the bags flat against the adhesive on selected panels and flaps of successive blanks as the blanks pass the cylinder to secure the bags to the blanks, and coordinating and aligning the delivery of the bags and the delivery of the blanks to ensure that the bags are accurately laid over said selected panels and flaps.

This method enables flexible bags having the minimum of seams to be laid accurately on the blanks, which may be treated with any desired pattern of adhesive, and in particular enable bags which are narrower than the blanks in one dimension and overlap the blanks in the other dimension to be applied easily and accurately to the blanks without elaborate means being required for registration beyond synchronizing the delivery of the blanks to the rotation of the cylinder.

Preferably the delivery cylinder is perforated and the bag material is held against it by vacuum applied to the interiof of the cylinder. This avoids the necessity for elaborate means for maintaining the bag in contact with the cylinder. Preferably the bag material is sealed and severed along adjacent non-coincident transverse lines on the cylinder, Drarerablv by coac-ion with an adjacent, oppositely rotatin' cylinder, one o: said cylinders carrying a knife element and a heat sealing element, and the other cylinder carrying anvil means with which said elements coact. This provides for simple fabrication of the bags in a predetermined relationship to the delivery cylinder* The blanks will usually have four adjacent panels forming the walls of the blank for a rectangular carton, and in this case the bag material has a width equal to that of two adjacent panels, and the bag formed therefrom are laid over two such panels on each blank. Xn a preferred embodiment the bags are formed of such a length and are so positioned as to overlap the panels at both ends: the sealed ends preferably overlap by a distance equal to half the diagonal dimension of the carton when erected. This enables the cartons to be erected without the bag being pulled away from the carton walls, and the carton to be filled to all four of its bottom corners. Likewise, the open end of the bag should overlap at least sufficiently to enable a seal to be formed after the carton is filled. The invention also extends to apparatus for making the knocked down containers comprising paperboard cartons having flexible liquid-proof liners comprising feed means ai’for providing successive paperboard blanks having adjacent side panels ai end flaps extending from the ends of the side panels, conveyor means to advance the blanks endways on along a path, an adhesive applicator adjacent said path to apply a predetermined portion of adhesive to selected panels and associated end flaps of said blanks, a rotary delivery cylinder tangential and transverse to said path, feed means to apply a web of continuous laid-flat tubular bag material to tlie periphery of the delivery cylinder, adjacent transverse cutting and sealing means associated with the cylinder to cut and seal successive lengths of the bag material into separate tubular bags, each having one open and one closed end, means to adhere the bags to the delivery cylinder for rotation therewith into tangency with said blanks, the operation of the conveyor, the web feed means, and the cutting means being synchronized and aligned so that the bags are laid on the blanks so as to overlie the adhesive pattern applied to said selected panels and flaps with the remaining panels and flaps projecting to either side of the bags.

The invention further extends to containers whenever made using the above method or apparatus.

ZO For a better understanding of the invention, a preferred embodiment is described witii reference to the accompanying drawings, wherein: Figure I snows diagrammatically apparatus for applying adhesive to paperboard carton blanks, for forming bags from Zo tubular flexible material, and for assembling the blanks and bags, Figure 2 is a longitudinal section through parts of the apparatus of Figure 1, and Figure 3 shows diagrammatica1ly the folding and gluing of an assembled blank and bag in forming a container therefrom. 427 41 The carton blanks 10 which are shown in fche drawing each consist or a sheet of paperboard (which term as used herein includes corrugated or uncorrugated board) that has been cut and creased in a die (not shown) to define four rectangular side-forming panels 11, 12, 13 and 14, with flaps protruding beyond both ends of the panels for closing what will ultimately be the flat top and bottom ends of a cartono The panel 14 has a narrow flap 14c along its free edge. It should be understood that apart from certain basi features specifically described above, the exact form of the blanks forms no part of the invention, and the partieul forms of blank and knocked down carton shown are chosen for illustration only. The method and apparatus are of eou applicable to the production of various forms of lined knocked down cartons, in particular those described in our I copending application No.628/75 u In the course of forming the blanks into knocked down cartons, they have applied to them certain area3 of adhesive in' a pattern which varies according to the design and purpose of the cartons. In the example shown the centi panels 12 and 13 of each blank 10 have applied to them a first widthwise line of adhesive 20 which extends along whs will be the top end of the carton, and another such adhesit line 21 is applied near the opposite end. The line 20 cros fche juncture of the panels 12 and 13 which will form one corner of the carton. Various spots or areas 33 of adhesit - 6 4 27 41 are ilso applied ro certain of the flaps.

In ?. iator sthge of the forming process a flexible liner 30 is i?._d rlafc on the blank 10 as shown at the left sand end of 1’rnure 1 or the right hand end of Figure 3, over fhe adhesive lines 20, 21 to which it adheras. The liner is of material suitable for holding liquids, the material of the liner being chosen so as to be impermeable co the liruid that it is to hold. The liner illustrated may be a transparent polyethylene bag having a transverse seal 31 at one end and Open at its- other end 32. The bag material is of course chosen to suit the liquid or granular or other fluid material that the bag is to contain. The bag is laid over the central panels 12 and 13 and, when flat, is coterminous with the total width of these adjoining panels, pro15 truding beyond the ends of the panels over the flaps attached thereto. As will be seen, the longitudinal distance between the seal 31 and the adhesive line 20 (coincident with the top ends of the panels 12 and 13) should be at least half the length of the diagonal of the carton when erected.

The other end 32 of the bag should protrude beyond the adhesive line 21 sufficiently far to have adequate material to close the end 32 once the bag ha3 been filled. The spots of adhesive 33 on the flaps secure the bag to these flaps .

Apparatus for producing the knocked down containers is illustrated in Fig, 1. Carton blanks 10 that have been cut, creased and perforated, ready for gluing, are stacked in a feed tray 34 from which a rotary combing device 35 of conventional type delivers the blanks in succession to a conveyor 36 in a predetermined alignment. The blanks pass below a rotary gluer 37 which applies the adhesive lines 20, 21 and spots or areas 33, to each blank, as for example by means of raised elements 20*, 21*, 33’ (Fig. 2) which are supplied with glue from a pet 38 by rollers 39, 40.

The blanks travel, adhesive line 20 leading, under a rotating combiner cylinder 41 of a machine 42 which makes the bags 30 ahd positions them accurately on the blanks.

To hold the' blank 10 on the conveyor 36 the latter may be perforated and have a vacuum box (not shown) under it.

The machine 42 is basically a known machine for laying windows over openings in carton blanks (for example, a Mode] Triple A window machine made by International Paper Box Machine Company of Nashua, N.H., U.S.A.), but with importanl modifications described below* From a spool 43 extruded, seamless tubular bag stock 30’ passes in a predetermined alignment continuously between driven feed rolls 44, over an idler roll 45 and around a bob roll 46 Onto the combiner cylinder 41, the latter being perforate as at 41a, with vacuum applied to the interior of the cylinder through a line 41b so that the material 30* clings to the combiner cylinder without blousihg as the cylinder rotates. (For - 8 4274 simplicity on illustration, the perforations 41a are not shown in Fig. 2). Electrostatic properties of the tubular material 30‘ may also help in holding it against the cylinder Above the combiner cylinder is a cutting and sealing j cylinder 47 having rings 48 which retain an elongated knife and electrical heating bar 50 that register on each revolution of the cylinders with a longitudinal anvil 51 on the combiner cylinder. The tubular material 30’ is fed between the cylinders 41, 47 and the knife 49 severs the tubular srock 30’ (thus forming the open end 32 of a bag ), and, substantially coincidentally, the heating bar 50 forms the transverse seal 31 in a straight line just behind the line of severance. As an alternative to providing the heating bar 50, the tubular material can be provided with spaced apart transverse seals 31 before it is wound on the spool 43, and the knife 49 can sever the bags adjacent these seals. To ensure that successive bags are spaced apart by the same amount as the successive blanks 10 on conveyor 36, after a bag has been separated from the material ’ by the knife 49 the bob roll 46 is swung to the broken line position 46’, drawing the sealed, free end of the material 30’ away from the severed end of the just completed bag 30, this being accomplished by a roller 52 which runs on a cam 53 of cylinder 47, the roller 52 and bob roll 46 being at opposite ends of a rocker 54 that pivot3 about the axis of idler 45. Successive bag lengths are severed on successive rotations of cylinder 47. The bags travel with their sealed ends leading. The feeding of blanks 10 is synchronized with the action of the gluer and with the spacing between bags fonned -it the combiner cylinder to bring the bags precisely into the position shown in Fig. 1 as the bags pass under the combiner cylinder and are pressed thereby against the adhesive lines 20» 21 and spots 33 on the blanks 10. Xt is to be noted that the bags cover the adhesive lines 20» 21 and spots 33» these being the only adhesive areas on the blank» so that no adhesive is transferred to the mechanisms that contact the blank.

The machine 42 can assemble a bag 30 and carton blai 10 on each revolution of the cylinder 41. The machine can be wide enough to run two parallel spools of material 30* L5_ and to handle two parallel lines of carton blanks» thus doubling its per hour output so that a production of at least six thousand knocked down units per hour can be achiei These flat units are devoid of exposed adhesive areas and if desired can be stacked for further processing as needed. 2a> Alternatively» the units may continue» as shown diagrammatically in Fig. 3 to be folded for setting up .into container: 48741 In this latrar case, there is of course no need to postpone the application of any additional spots or areas of glue that may he required and which are not immediately covered by the bags, and these may if desired be applied by the gluar 37, Fig. 3 illustrates the operations of a straightline folder-gluer of conventional type. Knocked down containers consisting of carton blanks 10 with bags 30 affixed thereto enter at the right hand end of Fig. 3, and are folded about the crease 123 between panels 12 and 13, to break this crease, the panels 11 and 12 being laid over the panels 13 and 14 and then returned to their original position. Then gluing means, for example rollers 50, apply adhesive 60 and 61 to the upper side (if not already treated) and the lower side of the edge flap 14c. Further required spots or areas of glue 59 may be applied to end flaps of the panels 11 and 14 by a glue spotter (not shown), if not already applied by the gluer 37. As a first step in setting up the container, the panel 14 having the flap I4c, is folded over the flat liner 30 so that the adhesive 60 on the underside of flap 14c adheres to the liner, as do the adhesive spots 59. With flap 14c in the position shown in the second blank from the left in Fig. 3, there is exposed adhesive 61 covering the other side of flap 14c. The panel 11 is then folded over, as shown in the left hand end blank in Fig. 3, to lie upon and adhere to the adhesive 61 on edge flap 14c. At this stage, the knocked down containers may be stored for subsequent use.

Claims (16)

CLAIMS :

1. A method of making knocked down containers comprising paperboard cartons with flexible liquid-proof liners, comprising applying adhesive to successive paperboard 5 carton blanks having a plurality of adjacent side panels and a plurality of flaps at each end, successively feeding the blanks tangentially and endways on past a rotating delivery cylinder, feeding continuous laid-flat tubular liner flexible / material lengthwise around the periphery 10 of the cylinder, forming said material while on the cylinder into successive separate tubular bags each having one open and one closed end by transverse cutting and heat sealing operations carried out on longitudinally adjacent portions of the material, holding the bags against the 15 surface of the cylinder while it rotates to apply the bags flat against the adhesive on selected panels and flaps of successive blanks as the blanks pass the cylinder to secure the bags to the blanks, and coordinating and aligning the delivery of the bags and the delivery of the blanks to 20 ensure that the bags are accurately laid over said selected panels and flaps.

2. A method as claimed in claim 1, wherein the delivery liner cylinder is perforated and the / material is held against it by vacuum applied to the interior of the cylinder. 26

3. A method as claimed in claim 1 or 2, wherein the tubular material is formed into bags of a length less than the length of the blanks, and the bags are laid on the blanl so as not to project beyond the longitudinal extremities of the blanks.

4. A method as claimed in any of the preceding claims wherein the paperboard blanks each have four adjacent rectangular panels for forming the sides of a rectangular carton and an edge flap on one of the panels for connecting 5. Sides of the carton, comprising applying the adhesive to the successive blanks across a pair of adjoining panels, and feeding the blanks successively past the delivery cylinder with a timing such that each bag covers said pair of adjoining panels of a blank and covers and adheres to 10 said adhesive and protrudes beyond the ends of said adjoining panels over associated end flaps,

5. A method according to claim 4, wherein the bags are sealed at one end, and the delivery of the bags to the blanks is timed so that the sealed ends of the bags overlap 15 the ends of said adjoining panels by a distance that is at least one half the length of a diagonal of one end of the carton when erected.

6. A method as claimed in claim 5, wherein the bag material is sealed and severed along adjacent non coincident 20 transverse lines on the delivery cylinder by coaction of an anvil on the cylinder with an adjacent, oppositely rotating cylinder carrying a knife element and a sealing element.

7. A method as claimed in any of claims 4-6, where said pair of adjacent panels are the central panels of paperboard blank, adhesive is applied to both sides of edge flap, and after application of the bag to the blar 5 the panel having the edge flap is folded to lay one of adhesive treated sides of the edge flap against the bac to adhere thereto, and the remaining panel is folded tc lie over the other adhesive side of the edge flap to ac thereto. I 10

8. A method as claimed in claim 7, wherein the adl applied across said pair of central panels comprises a pair of transverse adhesive patterns adjacent the ends said central panels.

9. O A method as claimed in any of claims 4-8, when 15 spots or areas of adhesive are applied both to the pan* and the end flaps of the blanks.

10. A method according to any of claims 1-6, where the adhesive is applied only to parts of the blanks wh will underlie the bags.

11. Apparatus for making knocked down containers comprising paperboard cartons having flexible liquid-pi liners, comprising feed means for providing successive paperboard blanks having adjacent side panels and end flaps extending from the ends of the side panels, convi 25 means to advance the blanks endways on along a path, an adhesive applicator adjacent said path to apply a predetermined portion of adhesive to selected panels and associated end flaps of each blank , a rotary delivery cylinder tangential and transverse to said path, feed means liner to apply a web of continuous laid-flat tubular / material to the periphery of the delivery cylinder, adjacent transverse cutting and sealing means associated with the cylinder to cut and seal successive lengths of the liner material into separate tubular bags each having one open and one closed end, means to adhere the bags to the delivery cylinder for rotation therewith into tangency with said blanks, the operation of the conveyor, the web feed means, and the cutting and sealing means being synchronzied and aligned so that the bags are laid on the blanks so as to overlie the adhesive pattern applied to said selected panels and flaps with the remaining panels and flaps projecting to either side of the bags.

12. Apparatus according to claim 11, wherein the delivery cylinder is a hollow perforated cylinder, and the means to adhere the bags to the cylinder is a vacuum source.

13. Apparatus according to claim 11 or 12, wherein transverse cutting and sealing means are mounted adjacent but not coincident with one another on a counterrotating cylinder coacting with said delivery cylinder.

14. Apparatus according to any of claims 11 to 13, including a straight line folder-gluer adjacent said conveying means downstream of the delivery cylinder, the folder-gluer being arranged to engage the panels projecting to either side of the bag to fold them over the bag, and to glue them to each other and to the bag along· an overlapping edge flap.

15. Apparatus for making knocked down containers substantially as hereinbefore described with reference 5 to the accompanying drawings.

16. A knocked down container, whenever made by the method or apparatus of any of