Cartons

B. A. FRANCIS

CARTONS

Feb. 6, 1968

Filed Dec. 27, 1966

3,367,553

Sheets-Sheet 1

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ATTORNEY

B. A. FRANCIS

CARTONS

Feb. 6, 1968

Filed Dec. 27, 1966

3,367,553

Sheets-Sheet 2

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<img file="US3367553A_D0003.tif" />

B. A. FRANCIS

CARTONS

Feb. 6, 1968

Filed Dec. 27, 1966

3,367,553

Sheets-Sheet 3

<img file="US3367553A_D0004.tif" />

B. A. FRANCIS

CARTONS

3,367,553

Feb. 6, 1968

Filed Dec. 27, 1966

Sheets-Sheet 4

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<img file="US3367553A_D0006.tif" />

/7G./J /76./4.

United States Patent Office „ . 3,367,553

Patented Feb. 6, 1968

2

3,367,553 CARTONS Bernard Arthur Francis, Rayleigh, England, assignor to Pembroke Carton &amp; Printing Co. Limited, Basildon, England

Filed Dec. 27,1966, Ser. No. 604,718

Claims. (Cl. 229—17)

ABSTRACT OF THE DISCLOSURE

A lined carton has end closure flaps comprising a pair of side flaps and a pair of front and back flaps of which the back flap is deeper than the front flap. The liner is heat sealable, is stuck to each side flap in a region close to its fold line, and is deeper than the front flap and less 15 deep than the back flap. The side flaps are swung apart so that the liner is drawn out to form a fin which extends in parallel spaced relation to the fold lines of the front and back flaps. The front flap is folded in, the fin is heat sealed, and the sealed fin is folded to overlie the front 20 flap. The side and back flaps are folded in and secured so that end portions of the sealed fin are folded to lie between two of the closure flaps and the back flap overlies the sealed fin and the front flap, so as to clamp the liner to the carton at said end portions of the sealed fin 25 and along the sealed fin. One of the side flaps has a displaceable portion in the region to which the liner is stuck which portion when displaced forms a pourer hole in the liner.

This invention relates to lined cartons e.g. cardboard cartons having heat sealable liners, intended for packaging liquids, granules or powders. The invention is concerned with lined cartons of the kind (hereinafter referred to as cartons of the kind described) in which the ³⁵carton has, at at least one end, opposite pairs of separate end closure flaps which are folded down in succession with at least one flap of one pair lying on top of the other pair, to close the end of the carton. In cartons of this kind, the mouth of the liner at the end in question is heat sealed in a manner (hereinafter referred to as the manner hereinbefore described) to form a socalled “fin” extending right across the mouth of the liner, thereby closing the mouth. To explain this mat- ,_rter further, the liner, which is tubular in form, is pressed ° flat at its mouth so as to present, simply, two wall portions extending between a single pair of folds in the liner, the wall portions each having a free edge, which free edges together make up the mouth of the liner, without _5Qany pleats in the liner folded to lie between these wall portions.

By avoiding pleating the liner, no point of weakness in the seal occurs such as might allow liquids or fine powders to escape. ₅₅

Broadly, according to the present invention, in a carton of the kind described, in which the liner is sealed at at least one end in the manner hereinbefore described, end portions of the fin seal are folded in with said end closure flaps so as to clamp the liner to the carton. _coMore specifically, according to the present invention, the front and/or the back flap or flaps at said end of the carton are first folded and end portions of the “fin” seal at that end are then folded to lie to the outside of said first folded flap or flaps and immediately beneath the side flaps.

According to a feature of the present invention, the front flap may have a height equal to half the width of the side flaps, and the front flap may be first folded, whereafter the “fin” is folded to overlie the front flap 70 prior to folding the end portions of the fin seal.

According to a further feature of the present inven tion, the back flap may be folded to overlie the “fin” after the fin has been folded to overlie the front flap in accordance with the preceding feature.

With a construction in accordance with either of the last two described features of the invention a central portion of the fin is folded in with the end closure flaps along with end portions of the fin seal (which end portions include end portions of the fin), whereby the liner is securely clamped to the carton end in two directions at right angles and over the full extent of the sealed end of the liner.

According to a further feature of the present invention, in order to provide a pouring device for the carton, which may be a “one-shot” pouring device or alternatively a re-closable pouring device if the contents of the carton are not to be emptied at the one time, one of said side flaps is provided with a perforated, liftable, cut-off or tear-off portion adhering to the wall of the liner, beyond the fin seal, which portion when lifted, out or torn off, tears a hole in the wall of the liner through which possibly after manipulation of-the carton, the contents of . the carton may be poured.

In the case of a “one-shot” pouring device, the liftable cut-off or tear-off portion may be bounded by the hinge fold of said one of said side flaps whereby the hole cut or torn in the liner wall has an edge extending along said fold line. By flexing the adjacent carton side wall outwardly along said fold line a pouring lip may then be formed. Said adjacent carton side wall may be precreased so that this pouring lip is more easily formed. This is, hereinafter, more fully described. The liner is preferably also stuck to said adjacent carton side wall in a region close to said fold line. This facilitates tearing off a tear-off portion forming a pouring device. It also facilitates folding the liner to lie between the front and back flaps and the side flaps when the carton end is being closed. To this end, in practice, the liner would be stuck to both side flaps and to the carton side walls adjacent each of the side flaps close to the hinge fold lines of the flaps. By sticking the liner to both side flaps, the side flaps may be swung out to spread the mouth of the liner when the sealing fin is being formed. The liftable, cut-off or tear-off portion may be semi-elliptical but is preferably of right angled triangle shape, bounded by the side flap fold line and lines extending from the ends of the fold line at 45° thereto to intersect at right angles at a point spaced inwardly from the edge of the side flap parallel with its hinge fold line. The liner is preferably stuck to this triangular portion over its whole extent, because this facilitates folding the liner when the carton end is being closed, the liner preferably being folded along corresponding 45° fold lines to form a triangular gusset lying flat on the underside of the side flap. (With these preferred features, a cut-off or tear-off portion has to be provided to form a pouring hole.) The same arrangement is preferred at the other side flap. Conveniently the carton is dimensioned so that the two side flaps may be folded down to lie edge to edge and not overlap. With a one-shot carton the side flaps can be stuck down. Where a re-closable pouring device is required this is not the case as will hereinafter appear. An opening may conveniently be provided in the side flap with the triangular, liftable cut-off or tear-off portion bounded in part by the apex of the triangular portion so that its apex may be grasped by the fingers to lift it, whereafter it may be cut or torn off if so intended by the construction.

. The front flap conveniently has a dimension between its hinged edge and its parallel edge equal to one half the corresponding dimension of the back flap, the back flap being large enough to cover over the whole of the end of the carton. The back flap is preferably stuck down on to

3,367,553 the front flap which is, of course, folded first in this arrangement. Such adhesion gives rigidity to the carton and assists it to retain its rectangular form during handling and opening.

According to a further feature of the invention, where a re-closable pouring device is required, the liftable or tear-off portion lies wholly away from the hinged edge of the side flap in which it is formed and preferably wholly within the periphery of the side flap, and the side flap is releasable so that it may be raised and reclosed. It will be appreciated that in this case the hole or slit formed in the liner when the liftable or tear-off portion is lifted or tornoff, is isolated from the liner contents by the fold of the liner gusset underlying the folded down side flap, this fold corresponding with the slit formed in the liner in the previously described, one-shot construction in which the tearoff portion is bounded by the hinge fold line of the side flap in which it is formed.

By raising the side flap however, and flexing the carton, this fold is straightened so that the contents may be poured from the carton into the gusset and then out of the gusset through the slit formed by the liftable or tearoff portion, the gusset then forming in effect a nozzle leading from the carton.

To reclose the carton, the side flap is folded down so that the contents of the carton are again isolated.

The liner is preferably stuck to the front flap over its whole extent. This ensures that a rectangular opening is presented by the liner when the end closure flaps are open for filling the carton. It also firmly positions the fin seal on the outside of the front flap when the end closure is folded.

The liner is also preferably glued to the carton side walls as convenient to ensure that the liner maintains its proper position in the carton.

Specific embodiments of the present invention will now be described by way of example with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of one end of a lined carton according to the present invention, with the end closure flaps and the liner shown open ready to receive the intended contents of the carton, the carton incorporating a “one-shot” pourer device provided in accordance with a feature of the present invention.

FIGS. 2, 3, 4, 5 and 6 are corresponding perspective views of the carton shown in FIG. 1 showing stages in forming the end closure of the carton.

FIG. 7 is a perspective view showing the operation of the pourer.

FIG. 8 is a perspective view corresponding with FIG. 1 of one end of a further lined carton according to the present invention, incorporating a re-closable pourer device in accordance with a feature of the present invention.

FIG. 9 is a view corresponding with FIG. 6 showing the carton of FIG. 8, the end closure of the carton having been formed.

FIG. 10 is a perspective view showing the operation of the pourer incorporated in the carton of FIGS. 8 and 9.

FIG. 11 is a perspective view corresponding with FIG. 4 showing a stage in the formation of an end closure of a still further lined carton according to the present invention, the carton incorporating the same “one-shot” pourer device as the carton illustrated in FIG. 1.

FIGS. 12 and 13 are perspective views showing further stages in the formation of the end closure of the carton illustrated in FIG. 11 and

FIG. 14 is a perspective view of the carton shown in FIGS. 11, 12 and 13 showing an initial stage in forming the pourer, which operates generally as shown in FIG. 7.

In FIG. 1 the opposite pairs of end closure flaps and the liner are shown open ready for example, to receive the intended contents of the carton. After filling, the liner 10 is “fin” sealed as indicated in FIGS. 2 and 3. In the embodiment being described, the liner 10 is stuck to the side flaps 12 in triangular regions indicated at 13 in FIG. 1.

Thus the flaps 12 may be swung apart as indicated in FIG. 2 so as to draw out the liner 10 to form the “fin.” The “fin” is thereafter heat sealed, for example, either by its passage between heated rollers or by clamping the fin between a 5 pair of heat sealing jaws. After heat sealing the carton end appears as shown in FIG. 3.

The front flap 15 is also stuck to the liner 10 whereby the flap is automatically folded down when the side flaps 12 are swung apart to form the “fin.” ₁₀ The front flap 15 has a height equal to half the width of the flaps 12 and its leading edge is disposed along the fold line of the “fin.” The “fin” is folded forward to overlie the front flap 15 as shown in FIG. 4. The liner is, therefore, in the region of the “fin” doubled over the edge 15 of the front flap 15.

A portion of the front flap 15 adjacent its hinge fold line with the front wall panel 20 of the carton is left uncovered by the fin and carries a dry adhesive glue strip 21 for example (see FIG. 4) for securing down the back flap 2q 23 which is next folded as illustrated in FIG. 5. The liner carries a glue strip 21α for additionally securing down the back flap 23.

This leaves two generally triangular lining portions 24 (see FIG. 5) projecting from the side edges of the back 25 flap 23 one on each side and stuck to the side flaps 12.

The flaps 12 have dry adhesive glue strips 26 for example for securing down the flaps 12 which are next folded to overlie the back flap 23, as shown in FIG. 6, at the same time doubling the portions 24 of the liner over the side 30 edges of the front and back flaps 15, 23 whereby the portions 24 are clamped or gripped between the front and back flaps and the side flaps.

The advantage of the end closure as described is that the sealed liner is physically gripped and supported by the 35 end closure flaps 12, 15 and 23 by being doubled over and folded in with the end closure flaps in two directions at right angles over the full extent of the end wall of the liner.

According to the present invention, the liner is interlocked with the carton at at least one, and preferably both 40 ends so that it cannot easily pull away from the carton. The whole package is accordingly strengthened and made more rigid.

A carton according to the present invention is particularly useful for packing liquids which are generally far 45 heavier than corresponding volumes of granular or powdered fillings.

Such liquid fillings have a tendency to bow out the carton side walls, dragging the top of the liner away from the carton end closure, particularly during transportation 50 when the cartons may be subjected to shock loading. This can damage the liner.

By clamping both ends of the liner into the carton end closures, the liner is more rigidly and effectively supported by the carton body which tends to hold the liner 55 stretched out between the carton body ends, thereby additionally supporting the liner against bulging.

In the example just described both end closures of the carton are formed as described and this is preferred. However one only of the end closures may be formed as 00 described the other being formed in any other known or convenient fashion.

The carton of FIGS. 1 to 6 is provided with a “oneshot” pouring device which will now be described. One of the side flaps 12 has a perforated cut-off or tear-off 65 portion 50 the inner face of which corresponds with the glued area 13 of the flap, i.e. the area over which the flap is glued to the liner 10. The portion 50 is bounded by the hinge fold 51 of said one flap 12 whereby the hole 52 (see FIG. 7) torn in the liner wall when the portion 70 50 is removed has an edge 53 extending along the fold line 51. By flexing the adjacent carton side wall 54 outwardly as shown in FIG. 7 along the fold line 51, a pouring lip is then formed as shown in FIG. 7.

The side wall 54 is pre-creased as illustrated so that 75 this pouring lip is more easily formed. Thus a vertical

3,367 ..,.5 crease line 56 parallel with and midway between the side edges of the side wall 54 joining the fold line 51 with the apex of a triangle of creases of which the base line crease 57 is parallel with the fold line 51 and extends from side to side right across the side wall 54 the other two creases 5 58 extending upwardly at 45° from the two ends respectively of the base line crease to intersect the vertical crease 56.

The liner 10 is stuck to the side wall 54 in a region adjacent the fold line 51. This facilitates tearing off the portion 50 to form the pourer. It also facilitates folding the liner to lie between the front and back flaps 15, 23 and the side flaps 12 when the carton end is being closed in the manner previously described. To this end the liner is stuck to both side flaps 12 and the carton side walls ad- 75 jacent each of the side flaps 12 close to the hinge fold lines of the flaps.

The tear-off portion 50 may be semielliptical but it is preferably of right angled triangle shape, bounded by the fold line 51 and lines 60 extending from the two ends re- 20 spectively of the fold line 51 at 45° thereto to intersect at right angles at a point spaced inwardly from the edge of the side flap 12 parallel with its hinge fold line 51. The liner is suitably stuck to this triangular portion over its whole extent because this facilitates folding the liner 25 when the carton end is being closed, the liner preferably being folded along corresponding 45° fold lines to form the triangular gusset portions 24 previously described.

Conveniently the carton is dimensioned so that the two side flaps may be folded down edge to edge and not over- 30 lap. With the “one-shot” pourer being described the side flaps 12 are stuck down. Where a re-closable pouring device is required this is not the case as will hereinafter appear.

An opening 62 is conveniently provided in the pourer 35 flap 12 which is bounded in part by the apex of the triangular portion 50 so that its apex may be grasped by the fingers to lift it whereafter it may be cut or torn off.

The front flap 15 has a dimension between its hinged edge 64 and its parallel edge equal to one half the corre- 40 sponding dimension of the back flap 23, the latter being large enough to cover over the whole of the end of the end of the carton. The back flap 23 is stuck down onto the front flap 15 to give rigidity to the carton to assist it to retain its rectangular form during handling and opening. ⁴⁵

With the “one-shot” pourer construction described, by tearing off the portion 50 which as shown in FIG. 6 is exposed on the top end closure of the carton, a slit is formed in the carton lining 10 lying along the fold line _so51 and accordingly along the edge of the pouring lip. The slit may be opened by flexing the carton as shown in FIG. 7 and such flexing forms a pouring lip by bending the carton side wall along the fold line 51 and the lip forming crease lines 56, 57, 58. ₅₅

Referring now to FIGS. 8, 9 and 10 these show a reclosable pouring device in which a liftable tear-off or cutoff portion lies wholly away from the hinged edge 51 of the side flap 12 and, in this construction wholly within the periphery of the flap 12. Also the side flap instead of ₆₀being stuck down as previously described is releasable so that it may be raised and reclosed.

It will be appreciated that in this case the hole or slit 70 (see FIG. 10) formed in the liner 10 when the portion 50α is cut-off or torn-off, is isolated from the liner 65 contents by the fold of the liner gusset portion 24 underlying the folded down side flap 12 having the portion 50α, this fold corresponding with the slit formed in the liner in the previously described, “one-shot” pourer construction in which the tear-off portion is bounded by the hinge 70 fold line 51 of the side flap 12.

By raising the side flap 12 however, and flexing the carton this fold is straightened so that the contents of the carton may be poured from the carton into the gusset 24 and then out of the gusset through the slit or hole formed 75 ,553 by the liftable, cut-off or tear-off portion, the gusset then forming in effect a nozzle leading from the carton generally as shown in FIG. 10.

To reclose the carton the flap 12 is folded down so that the contents of the carton are again isolated.

To hold the flap down it is provided with a tongue 71 which can be pushed through a slot 72 in the other side flap 12. The tongue has a free edge tear-off portion 75 (see FIG. 9) which is initially stuck to the other side flap 12 to hold the tongued side flap 12 closed when the carton is initially packed.

The liftable cut-off or tear-off portion 50a is conveniently of similar triangular shape to the portion 50 previously described but having its base line parallel with and spaced from the hinge fold line of the side flap 12 in which it is formed. An aperture 62 is formed in the side flap as previously described to enable the portion 50α to be lifted or torn-off. Whether the portion is intended simply to be lifted or torn or cut off the base line of the triangle is conveniently extended as a crease at 80 to the two side edges of the flap 12 so that the side flap may be folded back as illustrated in FIG. 10 along the base line of the triangle when the pouring device is operative, to leave the apex of a liftable triangular portion 50α for example projecting from the fold in the side flap to form a pouring lip. The liner 10 is stuck to the front flap 15 over its whole extent. This ensures that a rectangular opening is presented by the liner when the end closure flaps 12, 15, 23 are open for filling the carton. It also firmly positions the “fin” seal on the outside of the front flap 15 when the carton end closure is folded.

The liner 10 is preferably glued to all four of the carton side walls to ensure that the liner maintains its proper position in the carton.

An alternative folding sequence for a carton end closure of a carton according to the present invention is shown in FIGS. 1, 2, 3, 11, 12, 13. Thus the carton is constructed and folded as has previously been described with reference to FIGS. 1, 2 and 3. After the “fin” has been doubled over the leading edge of the front flap 15 as shown in FIG. 11 the side flaps 12 are next folded, as shown in FIG. 12. The glue strip 21α previously described is omitted from the liner in the present construction but glue strips 26α are provided on the flaps 12 to adhere to the glue strip 21α on the flap 15.

The back flap 23 is finally folded down to close the end of the carton, as shown in FIG. 13, the back flap being provided with a glue strip 28α (see FIG. 12) to seal it down. The flap 23 may have an extension 29 in this construction (see FIGS. 12 and 13) which carries a glue strip 30 to seal the extension flap 29 against the front wall 20 of the carton as shown chain dotted in FIG. 12.

With the carton construction described with reference to FIGS. 1, 2, 3, 11, 12, and 13 the liner 10 is doubled over all three free edges of the front flap 15 which is supported by being glued to the side flaps 12 at 21α the side flaps 12 in turn being supported by being glued to the back flaps 23 at 28α the back flap bridging the carton end and possibly with an extension flap 29 being supported by the front and back walls of the carton. Thus again the sealed liner is physically gripped and supported at at least one and preferably at both ends by the end closing flaps to lend strength to the carton.

In the carton described with reference to FIGS. 1, 2, 3, 11, 12 and 13, the carton is provided with a “one-shot” pouring device as described with reference to FIGS. 1 to 7.

To give access to the tear-off portion 50 which in this construction is covered over by the flap 23 the latter has a tear-off portion 90 of triangular shape dimensioned so that when it is torn off it fully exposes the portion 50 and the aperture 62 in the underlying flap 12 as shown in FIG. 14. The pourer may then be formed generally as hereinbefore described with reference to FIG. 7.

The portion 50α of the re-closable pourer described with reference to FIGS. 8, 9 and 10 is adhered to a co3,367,553 extensive, underlying apex portion of triangular gusset 24. When the portion 50α is lifted therefore the triangular apex portion or corner of the gusset is likewise lifted through the hole thus formed in the flap 12 and the corner of the gusset must be cut or torn off with the por- 5 tion 50α to form a slit which opens to make the hole 70 shown in FIG. 10.

The gusset portion 24 may be stuck to the underside of the flap 12 in FIGS. 8, 9 and 10 over an area which is larger than and wholly includes within its periphery ₁₀the portion 50α. In this case the portion 50α may simply be lifted to tear a hole in the gusset to form the pourer. The portion 50α then forms a pouring lip and the crease 56 is conveniently extended to its apex. Similar considerations apply to the construction shown in FIG. 1. If the 15 triangular portion 50 is stuck to the underlying gusset wholly within the periphery of the gusset for example by making its angles at the ends of the fold line 51 30° angles instead of 45° angles and the gusset is stuck to the underside of the flap 12 over the whole of its tri- 20 angular area 13, the portion 50 when lifted will tear a hole in the gusset to form the pourer and the portion 50 projects to form the pouring lip. In the same way the crease 56 is extended to the apex of the portion 50.