GB2295597A

GB2295597A - Wrapping groups of products

Info

Publication number: GB2295597A
Application number: GB9424225A
Authority: GB
Inventors: Andrea Cinotti
Original assignee: Wrapmatic SpA
Current assignee: Wrapmatic SpA
Priority date: 1994-11-30
Filing date: 1994-11-30
Publication date: 1996-06-05
Anticipated expiration: 2014-11-30
Also published as: DE4442641A1; GB2295597B; GB9424225D0

Description

1 2295597 A method for overwrapping groups of individually packaged

products in film material The present invention relates to a method whereby groups of products, in particular rolls of toilet tissue and kitchen paper already wrapped for sale as individual retail packs, can be overwrapped in a plastic film material. It is the practice currently to facilitate a large scale and convenient distribution of such products, especially in supermarkets and shopping centres, by assembling a number of retail size packs already wrapped for the shelf (typically two or four rolls wrapped in plastic film, or paper), and enveloping the assembled packs en bloc in plastic film. The ultra-large parcels thus obtained (containing maybe several tens or twenties of the retail packs) can be transported swiftly and with ease from the plece of manufacture to the point of sale, palletized if need be, whereupon the overwrapping is broken and the individual packs are removed and displayed. These giant parcels are wrapped utilizing automati machines which operate on the same principle as is 2 is adopted conventionally for wrapping smaller packs (disclosed for example in GB 988 273, US 3 303 630 and US 3 513 629), namely by assembling a plurality of individually wrapped packs at an initial statiorL and ordering them into a group, which thereupon is advanced and enveloped in a continuous plastic film material (polyethene) by a special purpose machine constituting the overwrapping station proper; this station is followed by a first heat-seal station, positioned to effect a continuous join between the overlapping longitudinal edges of the plastic film, thereby creating a tubular wrapper, and thereafter, a;econd heat-seal station by which the two open ends of the tubular wrapping are secured to effect a full closure. In practice, the second heat-seal station effects a single closure simultaneously securing the tail end of: one already finished wrapper and the leading end 2 oj' the next; the two are then separated by a cut. The solution of overwrapping packs in continuous cycle utilizing special purpose machinery imposes a notable burden of cost on manufacturers wishing to c- perate a complete wrapping line for paper rolls, g'ven that the machines in question are complex and expensive, and must be built especially to handle 3 is this type of product; moreover, such machines are unable in certain instances to guarantee a fully secure heat-seal at the two ends of the overwrap. Accordingly, the applicant now discloses a method for overwrapping groups of individually packaged products, in plastic film, such as will allow of fashioning a secure outer wrap that is obtainable without the use of special purpose equipment but preferably by means of non-continuous machines, adaptable to a variety of closure configurations according to requirements, and economical inasmuch as the end result is achieved without the need for dedicated machinery. The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which: -figs 1 and 2 illustrate two steps of the method according to the present invention for overwrapping groups of individually packaged products, viewed schematically and in perspective; - fig 3 shows the step of the method which follows that of fig 2, viewed in a frontal elevation; -figs 4 and 5 illustrate two further steps of the overwrapping method disclosed, viewed respectively in perspective and in a side elevation both with 4 certain parts omitted; -fig 6 illustrates a finished overwrapping produced by the method disclosed, viewed in perspective with certain parts omitted better to reveal others; -figs 7 and 8 illustrate a variation on certain of the steps shown in figs 1 to 5, respectively in a perspective view and in a side elevation; -fig 9 illustrates a finished overwrapping produced by the method disclosed, viewed in perspective and incorporating the variation of figs 7 and 8. As illustrated in the accompanying drawings, the method to which the present invention relates is one whereby groups of products 1, and in particular rolls of toilet tissue and kitchen paper already wrapped in small or standard size packs denoted 1p, can be overwrapped with a plastic film material. Packs Ip to be overwrapped are assembled initially at a station 2 (indicated schematically as a simple elevator 15), of which the function is to order the resulting plurality of the packs ip into a unit 3 of compact parallelepiped configuration. Use is made of a film material procured in single sheets 4, such as can be supplied from a relative magazine/work station (conventional in embodiment, therefore not illustrated) by which the sheets 4 will be held in stacks and advanced singly through a horizontal direction to the point of assuming a stable position within the operating compass of the overwrapping machine; the option also exists of using a continuous film cut into single wrapping sheets 4 at the selfsame magazine/work station. The overwrapping method according to the present invention comprises the following succession of essential steps: -a) wrapping the unit 3 composed of individually wrapped packs lp by raising the elevator 15 and causing the unit 3 to impinge on a single sheet 4 of film drawn out flat and extended in a horizontal plane directly above (see fig 1), thereby creating a tubular wrapper 6 (initially with three sides) with two open ends 7 each terminating in a pair of vertical appendages 8v and one top appendage 8s; -b) drawing the bottom edges 5 of the three-sided wrapper 6 into mutual contact, for example by means of a pair of longitudinal folders 161, and sealing the selfsame edges together by means of first heat seal plates 16 associated with the two folders 161 (see figs 2 and 3) so as to complete a fourth side terminating at each end 7 in a bottom appendage 8i; -c) enclosing each end 7 of the tubular wrapper 6 6 by flattening the leaves 8 of material that project beyond the dimensional compass of the unit 3, i.e. the appendages 8v, 8s and 8i, through the agency of relative folders 17, thereby creating at least one line L along which to effect a closure with one or more pairs of second heat seal plates 18 and thus secure the wrapper 6; -d) finally, separating the parts of the leaves 8 of film extending at each end 7 beyond the line L of the heat-seal effected during the previous steD, by means of relative knives 19. The steps described above thus permit of forming a wrapper 6 around several packs lp of products using a machine designed preferably for non-continuous operation, of which the embodiment is conventional and the constructional features are therefore not illustrated in detail; the wrapper 6 in question can be fashioned either as a total enclosure (i.e. substantially hermetic,, or in such a way that the contents remain partly exposed. More exactly, the configuration of the closure is diversifiable (see figs 4, 5 and 6), according to the manner.in which the leaves 8 extending from the two ends 7 of the wrapper 6 are folded and sealed: in the case of a partial closure, step c) would 7 involve making first lateral folds at the ends 7 of the wrapper 6, whereby each vertical appendage 8v is caused by a rotation of the relative folder 17 (see arrow F, fig 4) to bend along a corresponding axis coinciding with one vertical corner edge of the unit 3, in such a way as to leave two mutually opposed flat horizontal flaps 9 (top and bottom) which appear trapezoidal in plan and are of the same length (the two flaps 9 coincide effectively with the top and bottom appendages 8s and 8i). Thereafter, each flap 9 is heat-sealed in this same position along a relative line L and Li coinciding wiL the longer base of the trapezoidal outline, marginally beyond the vertical face of the endmost pack ip (see fig 5) and immediately adjacent to the horizontal top or bottom edge of the unit 3. This results in a partial closure at each end of the wrapper 6, that is, as discernible in fig 6, with two vertical panels enclosed and a central panel exposed. Where a totally enclosed wrapper 6 is required, the aforementioned step c) would involve an additional sequence of operations (see figs 4, 7, 8 and 9). First, as in the former instance, a fold made from the sides of the wrapper 6 results in the vertical 8 appendages 8v being bent along respective vertical axes coinciding with the upright corner edges of the unit 3, in such a way as to leave two mutually opposed flat horizontal flaps 9 and 9a appearing trapezoidal when viewed in plan. Thereafter, a second fold is effected using a third folder 21, by which the top flap 9a is engaged and bent toward the bottom flap 9 (see arrow F1, fig 8) to the point of assuming a predominantly vertical. configuration, flattened against the already folded vertical appendages 8v, partially overlapping the bottom flap 9, hence the bottom appendage 8i, and exibiting an "L" shape when seen in profile. Next, the flaps 9 and 9a are secured in this same configuration by a single heat- seal effected along the horizontal line L of contact between the two, marginally beyond the vertical face of the endmost pack ip and adjacent to one horizontal corner edge of the unit 3. Thus, the ends 7 of the wrapper 6 will be totally enclosed as illustrated in fig 9. In this solution, the condition required in order to secure an overlap between the two flaps 9 and 9a is that the length A at least of the top flap 9a snould be greater than the height of the wrapper 6, as indicated in fig 8.

9 In both solutions described, the final step of the method, as already intimated, will be to trim off the excess portions of the flaps 9 extending beyond the heat-seal lines. In both the end fold configurations indicated, the distance by which the leaves 8 of material project beyond the dimensional compass of the unit 3 is in practice uniform throughout, whereas the step of heat-sealing the ends 7 will be seen to differ, in that the partial closure involves securing each set of end folds with two horizontal and parallel seals effected along two lines L and L1 coinciding with two opposite corner edges of the relative end 7, whilst in the case of the total closure, a single heat-seal L is made along the bottom corner edge at each end 7. It will be evident that a plurality of products overwrapped by the method disclosed affords economy of manufacture, inasmuch as the wrapper itself is fashioned discretely and can therefore be produced by a non-continuous type of machine; in addition, there is the facility of adopting different pack configurations (in response to demand and according to the manufacturer's own requirements) without any need to alter the structure of the machine.

Claims

1) A method for overwrapping groups of products in plastic film material, in particular standard size packs of products assembled at a relative wrapping station and ordered initially into a compact unit of substantially parallelepiped configuration, characterized in that it comprises the steps of: -a) enveloping the assembled packs by directing the substantially parallelepiped unit against a single sheet of film drawn flat and extended across the relative path of movement, in such a way that the sheet of film is folded into a three-sided tubular wrapper with two open ends each terminating in a pair of vertical appendages and a top horizontal appendage of film projecting beyond the relative end face of the parallelepiped unit; -b) sealing together the free longitudinal edges of the tubular wrapper in such a way as to complete a fourth side terminating at each end in a projecting bottom horizontal appendage of film; -C) closing the two ends of the tubular wrapper by folding the relative appendages and applying a heat seal along at least one line at each end to effect the closure of the wrapper; -d) cutting away the portions of the appendages of film projecting at each end of the wrapper beyond the line of the heat-seal closure effected during the penultimate step.

2) A method for overwrapping groups of products in plastic film material, in particular standard size packs of products assembled at a relative wrapping station and ordered initially into a compact unit of substantially parallelepiped configuration, characterized in that it comprises the steps of: -a) enveloping the assembled packs by directing the substantially parallelepiped unit against a single sheet of film drawn flat and extended across the relative path of movement, in such a way that the sheet of film is folded into a three-sided tubular wrapper with two open ends each terminating in a pair of vertical appendages and a top horizontal appendage of film projecting beyond the relative end face of the parallelepiped unit; 12 -b) sealing together the free longitudinal edges of the tubular wrapper in such a way as to complete a fourth side terminating at each end in a projecting bottom horizontal appendage of film; -c) closing the two ends of the tubular wrapper by folding the relative appendages and applying a heat seal along at least one line at each end to effect the total enclosure of the wrapper; -d) cutting away the portions of the appendages of film projecting at each end of the wrapper beyond the line of the heat- seal closure effected during the penultimate step.

3) A.-i overwrapping method as in claim 1, wherein the closure step c) comprises the single operations, implemented in sequence, of: - effecting a fold at each open end of the tubular wrapper whereby the two vertical appendages are caused to bend along corresponding vertical axes coinciding with relative vertical corner edges of the parallelepiped unit in such a way as will bring about the formation of two mutually opposed flat horizontal flaps, coinciding respectively with the top appendage and with the bottom appendage, which exhibit a substantially trapezoidal outline when 13 viewed in plan and are of identical proportions; - heat-sealing each of the flat horizontal flaps along a line coinciding with the longer base of the trapezoidal outline, marginally beyond the vertical end face of the parallelepiped group and adjacent to a relative horizontal corner edge thereof.

4) An overwrapping method as in claim 2, wherein the closure step c) comprises the single operations, implemented in sequence, of: - effecting a first fold at each open end of the tubular wrapper whereby the two vertical appendages are caused to bend along corresponding vertical axes coinciding with relative vertical corner edges of the parallelepiped unit, in such a way as will bring about the formation of two mutually opposed flat horizontal flaps coinciding respectively with the top appendage and with the bottom appendage and exhibiting a substantially trapezoidal outline when viewed in plan; - effecting a second fold whereby the top flap is bent along a horizontal axis coinciding with a horizontal corner edge of the parallelepiped unit and directed toward the mutually opposed bottom flap, ultimately assuming a substantially vertical 14 position flattened against the vertical appendages, partly overlapping the bottom flap and exhibiting an I'Ll' configuration when viewed in profile; heat-sealing the two flaps one to another, along_ horizontal line coinciding with the portions in overlapping contact, marginally beyond the vertical end face of the parallelepiped unit and adjacent to a relative horizontal corner edge thereof.

5) 6) An overwrapping method as in claim 1, wherein the appendages of the tubular wrapper extend a uniform distance beyond the end faces of the parallelepiped unit, and the closure of the wrapper is effected by applying a double horizontal heat-seal to each end along two parallel lines coinciding respectively with opposite edges of the relative end face.

An overwrapping method as in claim 1, wherein the appendages of the tubular wrapper extend a uniform distance beyond the end faces of the parallelepiped unit, and the closure of the wrapper is effected by the application of a single horizontal heat-seal to each end along a line coinciding with one edge of the relative end face.

7) 8) is An overwrapping method as in claim 4, wherein at least the top horizontal flap extends beyond the end face of the parallelepiped group by a distance greater than the height of the tubular wrapper.

An overwraping method as in preceding claims, as described and illustrated with reference to the accompanying drawings and intended for the stated objects.