GB2297957A

GB2297957A - Stabilizing end folding tabs of tubular wrapper

Info

Publication number: GB2297957A
Application number: GB9603120A
Authority: GB
Inventors: Fulvio Boldrini
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 1995-02-14
Filing date: 1996-02-14
Publication date: 1996-08-21
Anticipated expiration: 2016-02-14
Also published as: IT1280361B1; ITBO950049A1; DE19605111A1; GB2297957B; DE19605111B4; ITBO950049A0; GB9603120D0

Description

1 A method of wrapping products 2297957

The present invention relates to a method of wrapping products. The invention finds application, to advantage, in the art field of industrial processes for packaging items of substantially parallelepiped shape such as packets of cigarettes, soaps and similar items. Conventionally, products of the type in question are enveloped first in a completely enclosed or a cupped wrapping, whereupon a further wrapper is folded around each product in such a manner as to assume a tubular configuration with at least one axial end terminating in a tubular extension that projects axially from a relative end face of the product. The tubular extension in question comprises four flaps arranged in two mutually opposed and parallel pairs, which ultimately will be folded down flat against the relative end face of the product in such a way as to enclose the relative end of the tubular wrapper. The operation of folding the two pairs of flaps is carried out normally in two steps, of which the first consists in flattening the two flaps of a first pair against the end face of the product, with the result also that

2 two triangular end portions of the remaining two flaps are caused to bend inwards; in the second step, these same two remaining flaps are folded down against the end face and over the two flaps flattened previously.

The step of folding the second pair of flaps tends to be impeded by the aforementioned triangular portions, which are liable to separate from the inward facing surfaces of the corresponding flaps, and accordingly, it becomes necessary both to utilize folders such as will stay continuously in contact with the flaps of the first pair until the flaps of the second pair have been completely flattened, and, more especially, to utilize moving folders for the purpose of flattening the second pair of flaps.

The object of the present invention is to provide a method unaffected by the aforementioned drawbacks.

In particular, the object of the present invention is to provide a method such as will allow of using fixed folders for the step of flattening the flaps of the second pair. 1 The stated object is realized in a method according to the present invention, suitable for wrapping products of substantially parallelepiped shape each enveloped initially in a tubular wrapper of which at least one projecting end extends beyond one relative end face of the product and affords two first mutually opposed and parallel flaps, also two second mutually opposed flaps is 3 disposed transversely to the first flaps, comprising the steps of folding the first two flaps through 900 one toward the other and against the end face of the product, with the result that two triangular portions are made also to bend inwards from the respective ends of each second flap, then folding the second flaps one toward the other through 900 over the first tlaps and against the end face of the product, characterized in that it comprises the further step of stabilizing the triangular portions in a position of contact with the relative second flaps before the selfsame second flaps are folded. The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which: -fig 1 illustrates a first part of a wrapping device capable of implementing the method according to the present invention, viewed in perspective and with certain parts omitted in the interests of clarity; - fig 2 illustrates the part of the device as in fig 1, viewed in perspective and in a different operating position; -fig 3 illustrates a further part of the device as in fig 1, viewed in perspective; -fig 4 illustrates part of a further wrapping device capable of implementing the method according to the present invention, viewed in perspective and with 4 certain parts omitted in the interests of clarity. With reference to fig 1 of the drawings, 1 denotes a machine, in its entirety, by which packets 2 appearing substantially parallelepiped in shape are overwrapped with cellophane; one such packet 2 only is illustrated in the drawings. The machine 1 comprises a wrapping wheel 3 affording a plurality of peripheral pockets 4 each able to accommodate a relative packet 2 together with an outer wrapper 5, preferably of transparent material, which is already folded around the packet 2 in such a way as to assume a tubular configuration. The wrapper 5 exhibits at least one extended portion 6 projecting axially beyond a relative end face 7 of the packet 2, which is composed of two mutually opposed and parallel first flaps 8, also two mutually opposed second flaps 9 disposed at right angles to the first flaps 8 and parallel with a feed direction 10 along which the packet 2 is caused to advance, following a circular path P described by the wheel 3. The machine 1 further comprises a folding device 11 that coincides with a first folding station 12 located in a fixed position along the circular path P, and is equipped with a pair of folding heads 13 aligned along the feed direction 10, each exhibiting a transverse dimension which when measured parallel to the first flaps 8 will appear marginally less than the width of these same flaps 8. The folding heads 13 are capable is of movement back and forth along the feed direction 10 within the compass of the station 12, reciprocated by a suitable actuator device of conventional embodiment not illustrated in the drawings, between an at- rest position (see fig 1), in which the two heads 13 are separated one from another by a distance greater than the distance that separates the corresponding flaps 8, and an operating position (see fig 2) in which the heads 13 are disposed substantially in mutual contact. Each single head 13 exhibits a sole plate 14, of which the lower surface coincides with a plane substantially tangential to the end face 7 of a packet 2 occupying the folding station 12, a frontal plate 15 associated with and extending perpendicular to the sole plate 14 on the side opposite from the surface directed toward the wheel 3, also two side plates 16 disposed at right angles to the sole and frontal plates 14 and 15 and affording respective outward facing surfaces 17, each positioned so as to engage in contact with the inward facing surface of a respective second flap 9. In operation, when a packet 3 is brought together with the relative wrapper 5 into the folding station 12, the folding heads 13 will be drawn toward one another, hence away from the at-rest position occupied hitherto and into their operating position, with the result that the two flaps 8 of the first pair are rotated through 900 toward one another and flattened against 6 is the end face 7 of the packet 2. Moreover, not only do the heads 13 fold and flatten the first flaps 8, but each head also causes two triangular portions 18 at respective ends of the second flaps 9 to bend double along relative angled creases 19 and lie flat against the inward facing surface of the selfsame flaps 9. In order to stabilize the configuration of the second flaps 9 in such a way as will ensure that they can be folded toward one another subsequently and flattened thus in the required manner over the first flaps 8 and against the end face 7 of the packet 2, through the agency of conventional helical restraints 20 occupying respective fixed positions along the circular path P beyond the folding station 12, the relative triangular portions 1,8 are secured in their positions folded flat against the inward facing surfaces of the flaps 9, by means of a stabilizing device 21 associated with the folding station 12. observing the solution of figs 1 to 3, in which the material utilized for the wrapper 5 is heat-sealable, the stabilizing device 21 comprises a plurality of heat-seal elements 22, one for each of the triangular portions 18, capable of movement transversely to the feed direction 10 between an at-rest position (fig 1) in which the single element 22 is separated from the relative flap 9 by a given distance, and an operating position (fig 2) in which the element 22 engages the 7 relative flap 9 in direct contact at a point within the dimensional compass of the respective triangular portion 18, in such a way that this same portion 18 can be pinned against the corresponding side plate 16 of the relative head 13 and thereupon tacked to the respective flap 9, at a spot denoted 23 (fig 3). Once stabilized in this manner, the triangular portions 18 will keep the first flaps 8 firmly in contact with the end face 7 of the packet 2, thereby ensuring that the second pair of flaps 9 can be folded correctly and neatly by the fixed helical restraints 20. In the solution of fig 4, the material utilized for the wrapper 5 is not heat-sealable. In this instance, the stabilizing device 21 makes use not of heat-seal elements 22 but of pressure elements 24, which might also be heated, for example by internal electrical resistances that are not illustrated. Each pressure element 24 comprises a push rod 25, and a pressure plate 26 associated with the end of the rod offered to the packet 2. Each push rod 25 is capable of movement transversely to the feed direction 10, toward and away from the packet 2, between an at-rest position (not indicated) in which the relative plate 26 is distanced from the relative flap 9, and an operating position (see fig 4) in which the plate 26 engages the relative flap 9 in direct contact at a point coinciding with the respective triangular portion 18, in such a way 8 that this same portion 18 can be pinned against the corresponding side plate 16 of the relative head 13 and the angled crease 19 pinched, with precision, so as to hold the triangular portion 18 in place against the inward facing surface of the flap 9. Likewise in this instance, the stabilization of the triangular portions 18 has the effect of maintaining the first flaps 8 flattened correctly against the end face 7 of the packet 2 so that the second flaps 9 can be folded neatly and accurately by the fixed helical restraints 20. Naturally enough, the stabilization of the triangular portions 18 in the position folded double against the inward facing surfaces of the relative flaps 9 can be effected by any given means other than those described and illustrated (for example glueing or rolling), all of which are embraced within the scope of the present invention.

1) claims 9 A method for wrapping products of substantially parallelepiped shape each enveloped initially in a tubular wrapper of which at least one projecting end extends beyond one relative end face of the product and affords two first mutually opposed and parallel flaps, also two second mutually opposed flaps disposed transversely to the first flaps, comprising the steps of folding the first two flaps through 900 one toward the other and against the end face of the product, with the result that two triangular portions are made also to bend inwards from the respective ends of each second flap, then folding the second flaps one toward the other through 900 over the first flaps and against the end face of the product, characterized in that it comprises the further step of stabilizing the triangular portions in a position of contact with the relative second flaps before the selfsame second flaps are folded.

A method as in claim 1, wherein the stabilizing step consists in securing the triangular portions and the second flaps of the wrapper one to another by creating at least one point of permanent contact between each triangular portion and the relative flap.

3) 4) 6) "7 A method as in claim 2, wherein the wrapper is made from a heat-sealable material, and each triangular portion is secured to the relative second flap by way of a spot seal.

A method as in claim 1, wherein the stabilizing step consists in pressing each triangular portion along an angled crease line by way of which the triangular portion is associated with the relative second flap.

A method as in claim-4, wherein the pressing step consists in the application of a compressive force by which each triangular portion and relative second flap engaged in mutual contact are pinched together.

A method as in claim 5, wherein the comp:essive forc is accompanied by the application of heat.

A method as in preceding claims, wherein the second flaps are folded toward one another and against the end face of the product through the agency of fixed folding means.

11 A method as in claim 7, wherein the fixed folding means consist in folding means of helical geometry.

9) A method of wrapping products, substantially as described with reference to the accompanying drawings.