GB1574542A

GB1574542A - Method of inserting a liner inside a case made of fibreboard or the like

Info

Publication number: GB1574542A
Application number: GB50494/77A
Authority: GB
Original assignee: Bowater Packaging Ltd
Current assignee: SCA Packaging Britain Ltd
Priority date: 1978-05-15
Filing date: 1978-05-15
Publication date: 1980-09-10

Description

(54) METHOD OF INSERTING A LINER INSIDE A CASE MADE OF FIBREBOARD OR THE LIKE (71) We, BOWATER PACKAGING LIM ITED, a British Company, of Bowater House, Knightsbridge, London, SW1X 7LR, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a method of inserting a liner inside a case made, for example, of fibreboard or the like so that material such as butter, margarine, jam or the like can subsequently be packed and transported in the case.

According to the present invention, we provide a method of inserting a plastics liner inside a case comprising locating a pre-formed liner bag over a jig having dimensions in cross-section marginally smaller than those of the case into which the liner is to be fitted, placing a case which is open at both ends upsidedown over the liner on the jig so that the bottom edges of the case sidewalls are in line with the top of the jig and forming the vase of the case by folding in lower end closure flaps thereof and during this folding in operation securing portions of the base of the liner bag to the base of the case, securing the flaps in position and subsequently removing the lined case from the jig.

Preferably, the free end of the liner bag is folded outwardly onto folded down top closure flaps of the case prior to removal of the case from the jig.

Preferably, the jig is fabricated from metal, wood or plastics and is provided with apertures in its top face to assist in passage of air to the interior of the liner when the liner bag is removed from the jig.

The jig may he rotatably mounted on a base.

Preferably, the jig has two projecting stops on two opposed side- walls thereof, the upper surfaces of which locate the top edges of the open ended case to ensure that the bottom edges of the case side walls are flush with the top of the jig.

Preferably, after the liner bag has been located on the jig, " ears " formed by bottom corners of the liner bag are folded inwardly to overlie the top of the jig. Then, after the open ended case has been located on the jig, the ears are manipulated through special slits or slots formed in inner end closure flaps of the case, and running inwards from and at right angles to the free edges of these flaps.

The invention is now described by way of example with reference to the accompanying perspective drawings, in which: - Figure 1 is a perspective exploded view of the jig; Figure 2 shows a liner bag on the jig; Figure 3 shows the bottom corners of the bag folded in and held in place by a weight; Figure 4 shows an open-ended fibreboard case placed over the bag on the jig; Figures 5 and 6 show two steps in the folding over of the end closure flaps of the case; Figure 7 shows the liner being folded back onto the case; and Figure 8 shows the lined case after removal from the jig.

Referring to the drawings, a jig 1 of the requisite size, i.e. a little smaller than the size of a case into which a liner bag is to be inserted, is made from suitable stiff material, e.g. ply-wood or metal, as shown in Figure 1. Preferably, the jig is slightly tapered from top to bottom, to enable a case easily to be located thereon, and subsequently to be removed. The jig 1, if desired, can be mounted directly on a bench or base 3, or can be pivoted so as to rotate about a vertical axis. On the sides of vertical faces 5, 7 of the jig, a stop 9 is provided to locate an open-ended fibreboard case or sleeve 11 (see Figure 4). Holes 13 are cflt in the top 15 of the jig to allow the passage of air, during mounting of a plastics liner bag 16 on the jig, and during removal of a lined case from the jig.

To insert a plastics liner bag 16 into a case, a liner bag 16, e.g. of polythene, is placed over the jig and the two corners or "ears" 17 at the bottom of the bag are folded in, as shown in Figure 3, so as to overlie the top of the jig and are retained in position, e.g. by a weighting plate 19.

An open-ended case sleeve 11 is then slid into position over the jig 1 until its edges 23 rest on the stops 9 at the side of the vertical faces 5, 7 of the jig 1.

The weighting plate 19 is now removed and the "ears" 17 of the bag are sandwiched between the end closure flaps of the base of the case. Preferably, slots 25 are provided in the inner and closure flaps 27 of the case, and as these flaps 27 are folded in, so the " ears " 17 are pulled through the slots 25 in the flaps 27 (see Figure 5). The outer end closure flaps 29 are then folded down and the case is fastened using adhesive tape 31 as shown in Figure 6. The open end of the plastics liner bag is then folded back over the folded back top closure flaps and sides of the case, as shown in Figure 7. Thereafter, the lined case is removed from the jig, as shown in Figure 8.Normally the act of removing such a case with a loose fitting liner bag 16 would mean that the liner bag would not remain at the bottom of the case, but with the described method, the " ears " 17 located in the slots 25 hold the liner bag 16 in place. It will thus be appreciated that the whole of the internal volume of the case is available for filling with the product to be packed.

The above-described method has been developed for the in-house or on-line assembly of lined boxes immediately prior to filling with product. The product can be any solid or semi-solid material that would normally permeate through a fibreboard case were the liner not present, e.g. semiliquid butter, warm preserves, fondants and the like. These may be put in at an elevated temperature and cooled in the case. The upper part of the liner is folded over after filling and the top flaps of the fibreboard case are then closed.

The blank for the case may have either a narrow slot (material actually removed) or a slit cut in the blank (no material re- moved). The "ears,' may be simply pulled through the sIots or slits, and may be fixed by adhesive tape if desired. The case is preferably formed of -fibreboard, which may be solid board, or single- or doubleply corrugated board.

WHAT WE CLAIM IS: 1. A method of inserting a plastics liner inside a case comprising locating a preformed liner bag over a jig having dimensions in cross-section marginally smaller than those of the case into which the liner is to be fitted, placing a case which is open at both ends upsidedown over the liner on the jig so that the bottom edges of the case side walls are in -line with the top of the jig and forming the base of the case by folding in lower and closure flaps thereof and during this folding-in operation securing the flaps in position and subse -quently removing the lined case from the jig.

2. A -method as claimed in claim 1 wherein the -free end of the liner bag is folded outwardly onto folded down top closure flaps of the case prior to removal of the case from the jig.

3. A method as claimed in claim 1 wherein the jig is provided with apertures in its top face to assist in passage of air to the interior of the liner when the liner bag is removed from the jig.

4. A method as claimed in claim 1, 2 or 3 wherein the jig is rotatably mounted on a base.

5. A method as claimed in any of claims 14 wherein the jig has two projecting stops an two opposed side walls thereof, the upper surfaces of which locate the top edges of the open ended case to ensure that the bottom edges of the case side walls are flush with the top of the jig.

6. A method as claimed in any one of the preceding clams wherein, after the liner bag has been located on the jig, "ears" formed by bottom corners of the liner bag are folded inwardly to overlie the top of the jig, whereupon, after the openended case has been located on the jig, the "ears"' art manipulated through special slits or slots formed in inner end closure flaps of the case, and running inwards from and at right angles to the free edges of these flaps.

7. A method of inserting a plastics liner inside a case, substantially as hereinbefore described with reference to the ac companying drawings

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. case or sleeve 11 (see Figure 4). Holes 13 are cflt in the top 15 of the jig to allow the passage of air, during mounting of a plastics liner bag 16 on the jig, and during removal of a lined case from the jig. To insert a plastics liner bag 16 into a case, a liner bag 16, e.g. of polythene, is placed over the jig and the two corners or "ears" 17 at the bottom of the bag are folded in, as shown in Figure 3, so as to overlie the top of the jig and are retained in position, e.g. by a weighting plate 19. An open-ended case sleeve 11 is then slid into position over the jig 1 until its edges 23 rest on the stops 9 at the side of the vertical faces 5, 7 of the jig 1. The weighting plate 19 is now removed and the "ears" 17 of the bag are sandwiched between the end closure flaps of the base of the case. Preferably, slots 25 are provided in the inner and closure flaps 27 of the case, and as these flaps 27 are folded in, so the " ears " 17 are pulled through the slots 25 in the flaps 27 (see Figure 5). The outer end closure flaps 29 are then folded down and the case is fastened using adhesive tape 31 as shown in Figure 6. The open end of the plastics liner bag is then folded back over the folded back top closure flaps and sides of the case, as shown in Figure 7. Thereafter, the lined case is removed from the jig, as shown in Figure 8.Normally the act of removing such a case with a loose fitting liner bag 16 would mean that the liner bag would not remain at the bottom of the case, but with the described method, the " ears " 17 located in the slots 25 hold the liner bag 16 in place. It will thus be appreciated that the whole of the internal volume of the case is available for filling with the product to be packed. The above-described method has been developed for the in-house or on-line assembly of lined boxes immediately prior to filling with product. The product can be any solid or semi-solid material that would normally permeate through a fibreboard case were the liner not present, e.g. semiliquid butter, warm preserves, fondants and the like. These may be put in at an elevated temperature and cooled in the case. The upper part of the liner is folded over after filling and the top flaps of the fibreboard case are then closed. The blank for the case may have either a narrow slot (material actually removed) or a slit cut in the blank (no material re- moved). The "ears,' may be simply pulled through the sIots or slits, and may be fixed by adhesive tape if desired. The case is preferably formed of -fibreboard, which may be solid board, or single- or doubleply corrugated board. WHAT WE CLAIM IS:

1. A method of inserting a plastics liner inside a case comprising locating a preformed liner bag over a jig having dimensions in cross-section marginally smaller than those of the case into which the liner is to be fitted, placing a case which is open at both ends upsidedown over the liner on the jig so that the bottom edges of the case side walls are in -line with the top of the jig and forming the base of the case by folding in lower and closure flaps thereof and during this folding-in operation securing the flaps in position and subse -quently removing the lined case from the jig.