GB2108085A - Sealed end carton - Google Patents

Abstract

A packaging container comprises an outer case 10 and an inner lining bag 46, the bag 46 being sealed at one end 50 and open at the other end 48. The container has a lay flat condition, and the side wall panels have end flaps 38, 42 at the said sealed end 50 of the bag which are hinged to an intermediate flap 40, and the said end flaps 38, 42 are diagonally creased 38A, 42A, the arrangement being that when the container is moved to the erected condition, the said flaps 38, 42 fold in two and inter-fold with each other so that the sealed end of the bag folds neatly without loss of volume. The container is preferably of square cross-section. <IMAGE>

Description

SPECIFICATION Sealed end carton This invention relates to packaging containers of the "lined" type which comprise an outer case and an inner lining bag, the latter being sealed so as to protect the container contents, which may be for example powdery material or the like which has to be protected from moisture ingress.

As can be appreciated, these lined containers are used for containing such as coffee granules, powdery foodstuffs and other contents, in relation to which the outer case, which is normally of cardboard, does not provide sufficient protection.

When producing packaging containers comprising simply cardboard material it is usual to produce these containers so that they can take up a flat condition for transportation, the containers in this condition conventionally being referred to as "lay-flats", and to erect the container the edges of the lay-flat are pushed together.

If a lined lay-flat is erected in this fashion, then the lining is usually in the form of a sealed sleeve, and both ends of the lining sleeve must be sealed after erection, which is difficult without specialised machinery. It is necessary of course to leave at least one end of the lining open until after erection, so that the contents can be charged into the container, but it is in some cases desirable that one end of the lining be sealed prior to the erection, so that the lining is in fact a sealed bag which has a flat condition.

However, difficulties are created in trying to erect a flat sealed bag inside a flat outer case of creased cardboard material, in that the sealed end of the bag is required to proceed from a flat condition to, for example, a square condition, and if the end sealing of the bag is achieved by means of a transverse seal, then that end of the bag must fold in moving from the flat condition to the erected condition.

The present invention is concerned with a design for the end of a lined packaging container which has a lay-flat condition, and the liner is a flat bag having one sealed end and one open end.

the outer case is adapted to be erected into a four sides tubular packing container, the lining bag extending lengthwise of the container and at one end of the container, the lower end, the lining bag is sealed, whilst at the top end it is open for charging the container contents thereinto.

In accordance with the invention, at the said bottom end, each of a pair of opposed walls has a bag folding flap having a diagonal crease line, the crease lines being inclined in the same direction when the container is in the lay-flat condition, the lining bag being adhered to said flaps, and extending below the bottom edge of the container so that when the container is moved to erected condition, the induced tensions in the bag in moving from a flat condition to a rectangular or square condition causes the said flaps to fold about the diagonal crease lines, and the diagonal crease lines take up a position extending from corner to corner, but respectively overlapping to define an X-formation, the bag also folding to follow the folds in the said flaps, whereby there is no effective volume inside the container.

Preferably, there is a third flap hingedly connected to one of the sides between the sides to which the first and second mentioned flaps are hinged, the said third flap also being hinged to the first and second flaps so that as the said first and second flaps fold about their diagonals and overlap to close the container end as the container is erected, the said third flap overlaps the said folded first and second flaps, to provide an end covering for the said end of the container.

It is preferred that there be a fourth flap on the fourth side at the lower end, which fourth flap can be folded over the third flap to complete the end closuring.

The said third flap folds automatically to the covering position with the folding of the first and second flaps about their diagonals, by virtue of the fact that the first and second flaps are hingedly connected to the third flap. The fourth flap may have a tongue or the like for engagement in a slot or aperture in the third flap, when in closing position.

The container may be square or rectangular in section, to which construction the invention has best application, but it is believed that the invention can also be applied to containers of other cross-section configuration, e.g. octagonal, triangular or the like.

The top end of the lining bag may be sealed in any suitable fashion and by any suitable means, for example as disclosed in our co-pending application No. 7914410.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, wherein: Fig. 1 is a plan view of a cut and creased cardboard blank with a lining bag attached thereto, and for erection into a container according to the invention; Fig. 2 shows the blank and bag of Fig. 1 after folding same to the lay-flat condition; Fig. 3, 4, 5 and 6 respectively are perspective views showing the bottom end of the lay-flat of Fig. 2 during erection thereof, the figures showing respective stages of the erection process; and Fig. 7 shows the interior of the lower end of the container when erected.

Referring to Fig. 1, in this drawing is shown a blank 10 of cut and creased material, such as cardboard, made up of four similar rectangular panels 12, 14, 16, and 18 hingedly interconnected along lines 20, 22, and 24. To the free edge of panel 18 is hinged a glue tab 26, whilst to the top ends of the panels 12 to 1 8 are respectively hinged cover flaps 28, 30, 32 and 34. Flap 34 is of square section of a side length equal to the width of each of the panels 12 to 18, as the blank is erectable into a square sectioned container as will be explained. The flap 34 may be provided with a tuck-in tab 36, in which case flap 30 would be omitted.

At the bottom end, the panels 12 to 1 8 are provided respectively with cover panels 38, 40, 42 and 44. The panels 38 to 42 are each of square configuration of side dimension equal to the width dimension of panels 12 to 18, and they are hinged together along the hinge lines 20 and 22. Panel 44 is freely hingeable independently about the bottom edge of panel 18.

Each of panels 38 and 42 is provided with a diagonal crease 38A and 42A, the said diagonal creases 38A and 42A being angled in opposite directions when the blank is in the opened out condition as shown in Fig. 1.

The panel 44 has a locking tab 44A, whilst panel 40 has a locking slot 40A.

Finally, a lining edge 46 of a width suitable for placement between the combined width of panels 14 and 16 is glued to the blank. The bag bas an upper open end 48 and a lower sealed end 50, the seal extending transversely of the bag at the lower end, and it has a length such that the seal 50 is at least slightly below the lower edges of panels 40 and 42 as shown, and the top end of the bag extends above the flaps 30 and 32 as shown. In the position shown in Fig. 1, the bag is flat. The bag will be of a material to protect the bag contents, when the container has been erected and sealed. The bag is glued not only to panels 14 and 16, but also to panels 40 and 42.

In order to erect the containers from the flattened out condition shown in Fig. 1, panel 12 and panel 38 are folded about line 20 and panel 18 and panel 34 are folded about line 24, so that the glue tab 26 underlies the free edge of panel 12. The tab 26 is adhesively connected to the free edge of panel 12, and in addition panel 12 and also panel 38 are adhesively attached to the upper side of the bag, as is panel 1 8, but panel 44 is left free.

This condition of the container, which is the lay-flat condition, is shown in Fig. 2, and it will be noticed that the crease lines 38A and 42A in this figure are inclined in the same direction.

Figs. 3 to 6 illustrate the sequence of erection of the container, at the bottom end, from the Fig.

2 position. To erect the container, the edges defined by creases 20 and 24 are pushed together, and this causes the outer case 10 of the container to move to a square sectioned configuration. At the lower end, the bag 46 is put under tensile stresses because the bag is being asked at the bottom end to move from the flat configuration shown in Figs. 1 and 2 to a square configuration. This has the effect of inducing the panels 38 and 40 to commence folding about the diagonal fold lines 38A and 42A, which, as will be seen from Fig. 1, are inclined in the same direction in the lay-flat condition of the container.

The crease line 42A folds upwardly and inwardly whilst the crease line 38A folds downwardly and attempts to move outwardly, but is prevented from doing so by virtue of being adhered to the bag 46.

As shown in Fig. 3, which is an initial stage, the panel 42A has commenced an inward folding action, and the panel 38A has folded about its diagonal fold line 38A, but also the panel 40, because it has connection with both panels 38 and 42, has commenced folding inwardly in a direction to close the end of the erecting outer case.

Fig. 4 shows a more advanced position in the closing operation, and it will be seen that the panel 40 has moved considerably towards closing the end of the outer case, and panel 38 and panel 42 have moved almost to a folded in two condition. The panels 38 and 42 move automatically into the overlapping relationship as shown, with the folded panel 42 innermost, and the folded panel 38 between the outermost panel 40 and folded panel 42.

Fig. 5 shows the bottom end of the container immediately prior to closing, and it will be seen that the fold lines 38A and 42A have in fact moved into a crossed position, and respectively extending diagonally of the corners of the container. The panel 40 has moved to a position covering the end of the container, and it simply remains for the cover panel 44 to be folded over panel 40, and the extension tab 44A inserted in the locking slot 40A as shown in Fig. 6.

As the end of the container closes as above described, the inner bag 46 folds in sympathy with the folding of the outer case, so that in fact, as shown in Fig. 7 which is a view looking at the inner base of the container, the bag material has folded about fold lines to define a generally Xshaped configuration, but there is no loss in volume of the container, and there has been no breaking of the seal of the bottom end of the bag. A hermetically sealed inner bag is therefore achieved.

The top end of the container after filling the container with the contents can be sealed in any suitable fashion.

A composite container of the kind illustrated in Fig. 2 can be erected, filled and sealed on commercially available machinery.

Although the embodiment described illustrates a square cross sectioned container, this is for illustrative purposes only as the invention is most adaptable to square cross-sectioned containers. It can be applied however to rectangular sectioned containers, although some overlap of the bag material must be tolerated in that the bag must extend below the bottom end of the container by an amount equal to the width of the larger side. It is also believed that the invention by suitable adaptation can be applied to containers of other than four sided cross sectional configuration e.g.

polygonal and triangular.

Any conventional materials may be used for the lining bag and outer case, but typically the outer case will be of cut and creased cardboard, whilst the inner bag will be of coated paper.

Sealing of the bag may be by heat sealing, or adhesive, or other suitable means.

Claims (6)

Claims

1. A lined packaging container which has an outer case and a liner and which has a lay-flat condition, the liner being a flat bag having one sealed end and one open end, the outer case being adapted to be erected into a multi-sided tubular packaging container, the lining bag extending lengthwise of the container and at one end of the container, the lower end, the lining bag is sealed, whilst at the top end it is open for charging the container contents thereinto, and wherein, at the said bottom end, each of a pair of opposed walls of the outer case has a bag folding flap having a diagonal crease line, the crease lines being inclined in the same direction when the container is in the lay-flat condition, the lining bag being adhered to said flaps, and extending below the bottom edge of the outer case so that when the container is moved to erected condition, the induced tensions in the bag in moving from a flat condition to a rectangular or square condition causes the said flaps to fold about the diagonal crease lines, and the diagonal crease lines take up a position respectively overlapping to define an Xformation, the bag also folding to follow the folds in the said flaps, whereby there is no loss in effective volume inside the container.

2. A packaging container according to claim 1, wherein there is a third flap hingedly connected to one of the sides between the sides to which the first and second mentioned flaps are hinged, the said third flap also being hinged to the first and second flaps so that as the said first and second flaps fold about their diagonals and overlap to close the container end as the container is erected, the said third flap overlaps the said folded first and second flaps, to provide an end covering for the said end of the container.

3. A packaging container according to claim 2, wherein there is a fourth flap on a fourth side at the lower end, which fourth flap can be folded over the third flap to complete the end closuring.

4. A packaging container according to claim 3, wherein the fourth flap has a tongue or the like for engagement in a slot or aperture in the third flap, when in closing position.

5. A packaging container according to claim 1, 2, 3 or 4, wherein the container is square or rectangular in section.

6. A packaging container substantially as hereinbefore described with reference to the accompanying drawings.