GB1598181A - Method of packaging bags - Google Patents

Description

(54) A METHOD OF PACKAGING BAGS (71) We, ÖREBRO PAPPERSBRUKS AB, a Swedish Company, of Box 926, S-701 30 6retro, Sweden, 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 state ment: The present invention relates to a method of packaging bags, and more particularly, but not exclusively, to a method of bundling valve-bags. By a valve-bag is meant here and in the following a sealed bag having a selfclosable inlet opening through which the bag can be filled. for example, and which is automatically closed, e.g. by the contents of the bag, when the device used for filling the bag is withdrawn from the inlet opening.

Such valve-bags are often used for bagging cement.

Previously, válve-bags have been packaged in bundles of 50. Since, in a flattened state the bottom-edge and the sealed upper edge of such a bag are thicker than the two remaining long edges of the bag, a bundle in which the bags are placed one against the other will be much thicker on two edges thereof than on the others. In order to avoid this uneven thickness of the edges of a bundle, it has been proposed to arrange the bags of a bundle in five groups of 10.In forming the bundle, the bags of the first group of 10 bags are laid flat one upon the other; the bags of the second group are folded such that the ends of respective bags of the second group do not lie upon each other or upon the ends of the bags of the first group; the bags of the third group are laid flat against each other in the manner of the bags of the first group; the bags of the fourth group are folded in the same manner as the bags of the second group, whilst finally the bags of the fifth group are placed flat against each other. In this way there is obtained a readily handled bundle of uniform thickness.

Dur. lg a bag-filling operation, the bags are removed singly from the bundle and manually fitted over a filling nozzle of a bag-filling machine.

In recent times, practice has leant towards the use of fully automatic bag-fitting machines, in which each bag is automatically removed from a bag magazine and fitted to the filling nozzle of the filling machine, such that the filling nozzle extends through the valve of the bag. If this placing of respective bags on the filling nozzle is to be effected smoothly without interruption, the bags must lie completely flat and even. The automatic insertion of the filling nozzle into the valve of a sack requires a high degree of precision. If the bags have been bundled in the aforementioned manner, i.e. in five groups often bags, the bag-magazine of the bag-fitting machine must be filled manually, it being necessary in conjunction herewith to smooth out the folded bags.Despite the fact that the bags have been smoothed, it is difficult to achieve the precision required, owing to the folds and irregularities which remain in respective bags as a result of being folded.

Accordingly, this invention consists in a method of bundling bags which comprises forming an elongate stack of said bags; placing a bundle-stiffening plate at at least each end of the stack; placing a respective element over each longitudinally extending edge formed by the mutually adjacent corresponding corners of the bags in order to support and protect the corners of the bags; each element being of such a length as to extend over the respective corner of each of said plates; and attaching said elements and the plates to one another.

If it is desired to stiffen the bundle still further, bundle-stiffening plates may also be inserted between selected bags within the stack.

In one embodiment of the invention, the elements, and thus indirectly the bags, are secured to the plates, and also to the intermediate plates when fitted, by ties placed around and tightened against the peripheral edge surfaces of said plates so as to sandwich the respective element portion between the edge of the respective plate and the respective tie.

Preferably, at least one tie is passed around the stack between the end plates to secure the elements against said stack.

To ensure a firm seating of the ties around the edges of respective plates, each plate may be provided with a circumferentially extending groove or channel. Alternatively, only the end plates need be provided with such a groove or channel.

The bundle-stiffening plate may be a one pierce structure, in which case the groove or channel is formed separately therearound, or they may comprise a three-layer laminate, in which case the length and breadth dimensions of the centre layer may be made smaller than the dimensions of the other layers, so as to leave a channel.

Instead of placing a tie around the comer elements at the position of the end plates, the tie or ties may be placed solely at a position or positions located between the two end plates, in which case the ends of the corner elements will be attached to respective end plate by some other suitable fastener devices, such as staples.

So that the invention will be more readily understood and further features thereof made apparent, exemplary embodiments of the invention will now be described with reference to the accompanying schematic drawings, in which: Figure 1 is a perspective view of a bundle of valve bags produced in accordance with the method of the invention; Figure 2 is a side view of part of a first embodiment of an external support plate; Figure 3 is a side view of part of a second embodiment of an external support plate; and Figure 4 illustrates an alternative method according to the invention.

In the embodiment illustrated in Figure 1, a plurality of valve bags I are placed in a bundle, with each bag standing on one edge thereof and with one side of a bag lying against a similar side of an adjacent bag. In its collapsed or flat state, each bag has the form of a rectangle with cut corners. Placed at each end of the bundle is a respective external support plate 2 while a plurality of inner support plates 3 are placed at respective selected positions within the bundle, the plates having the same shape as the bags in their collapsed or flat state. In the illustrated method, an inner support plate 3 is placed between the hundredth bag and the first bag of the next hundred. The plates 2 and 3 assist in rendering the bags more stable, for handling purposes etc.Elongate edge support elements 4 are arranged to hold the bags 1 and the inner plates 3 forming the bundle together and to protect the mutually adjacent corresponding corners of the bags from damage, the support elements having the form of sheet-like elements which have been given, e.g. by folding, a cross-sectional shape corresponding to the corner profile of the bags. The support elements used in the illustrated bundle of bags comprise so-called board material or corrugated cardboard, as will be seen more clearly from Figures 2 and 3. Each of the outer support plates has extending therearound a groove which forms a seating for a tie 5 capable of being tightened by means of a mechanical device not shown, thereby to clamp and secure the end parts of the edge support elements 4 in a manner to form a stable and firm package.In this embodiment the tie has the form of a flexible band or strap. A tie 5 has also been passed around the stack between the outer plates 2. In the embodiment illustrated in Figure 2, the support plate is a one piece structure with th groove being formed therein in a separate working operation. The reference 5 identifies the band located in the groove. In the embodiment illustrated in Figure 3, the outer support plate comprises three layers 2', 2" and 2"' which are bonded together to form a laminate. In this embodiment, the length and breadth dimensions of the centre layer 2" are smaller than those of the two outer layers 2' and 2"' so as to form a groove extending around the plate. The retaining band or strap, referenced 5, can be effectively tightened to clamp the respective end parts of the longitudinally extending edge support elements.

In order to make the bundle of bags still more stable, the inner plates 3 may also be provided with grooves in which further clamping bands can be placed and tightened around the bundle.

The valve of the bags of the stack is not identified in any of the Figures but it will be understood that the bags are conveniently placed so that the valves of said bags face in one and the same direction.

Although the end support plates 2 of the illustrated embodiment have grooves extending therearound for receiving the ties 5, such an arrangement is not absolutely essential since a sufficiently rigid and stable bundle can be obtained by passing a tie or ties solely around the corner elements at a location or locations between the end plates, and tightening the tie. In this case, however, the corner elements must be attached to respective end plates by some suitable means.

Such a method of forming a rigid and stable bundle of bags is illustrated in Figure 4, in which valve bags 1 are shown placed on respective ones of their edges with the sides of the bags facing each other, to form a bundle. As with the embodiment described with reference to Figures 1--3, each bag, when collapsed, is generally of rectangular shape with the corners of the rectangle cut away. As with the embodiment of Figures 1 to 3, a stable bundle of bags is formed by using two outer support plates 2 whose shape corresponds to that of a collapsed bag. For the purpose of holding the bundle of bags together and also to protect the corners of the bags, two elongate support elements are used comprising sheets 4 of cardboard.Each sheet 4 covers two adjacent edges of the bundle of bags and the edges of the bags lying therebetween, the sheets being folded to a shape corresponding to the profile of the corners of the bag. The support elements 4, which are also folded to the contours of the end plates 2 are attached to the outer surface of the support plates 2 by some suitable means; in the illustrated embodiment, staples 6 have been used. Extending around the packet of bags is a number of ties 5, which may comprise rope or some flexible material such as nylon or steel bands, or flexible metal wire, said ties being suitable for holding the elements 4 in engagement with the corners of the bags.

If desired, one or more inner support plates having the same shape as the bags in their collapsed condition may be inserted between two adjacent bags in the bundle.

Instead of cardboard, there may be used for the elongate edge support elements other stiff materials such as corrugated cardboard, board, paperboard, thin metal plate and wood fibreboard.

WHAT WE CLAIM IS 1. A method of bundling bags which comprises forming an elongate stack of said bags; placing a bundle-stiffening plate at at least each end of the stack; placing a respective element over each longitudinally extending edge formed by the mutually adjacent corresponding corners of the bags in order to support and protect the corners of the bags; each element being of such a length as to extend over the respective corner of each of said plates; and attaching said elements and the plates to one another.

2. A method as claimed in Claim 1, wherein bundle-stiffening plates are placed internally of the stack between selected bags therein.

3. A method as claimed in Claim 1 or Claim 2, wherein the plates and said elements covering said plates are attached to one another by means of ties which are placed around said elements in the respective regions of the edges of said plates and which are thereafter tightened so as to sandwich the respective element portion between the edge of the respective plate and the respective tie.

4. A method as claimed in Claim 3, wherein at least each of the plates at the ends of said stack has a channel or recess extending circumferentially around the periphery thereof for receiving a respective one of said ties.

5. A method as claimed in Claim I or Claim 2, wherein said elements are secured to the respective end bundle-stiffening plates by means of fastener devices, and wherein at least one tie is passed aroun the stack and said elements at a location between said end bundle-stiffening plates to secure said elements against said stack.

6. A method as claimed in Claim 5, wherein the fastener devices are staples.

7. A method as claimed in any one of the preceding Claims, wherein each element covers two mutually adjacent edges of the stack and the bag edges which extend between said mutually adjacent edges.

8. A method as claimed in any one of the preceding Claims, wherein the bundle-stiffening plates are made of board or cardboard, and the comer elements are made of board, cardboard, thin metal plate or wood fibreboard.

9. A method as claimed in any one of the preceding Claims, wherein the bags are valve bags (as hereinbefore defined).

10. A method of bundling bags substantially as hereinbefore described with reference to Figures 1 to 3 or Figure 4 of the accompanying drawings.

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

Claims (10)

**WARNING** start of CLMS field may overlap end of DESC **. together and also to protect the corners of the bags, two elongate support elements are used comprising sheets 4 of cardboard. Each sheet 4 covers two adjacent edges of the bundle of bags and the edges of the bags lying therebetween, the sheets being folded to a shape corresponding to the profile of the corners of the bag. The support elements 4, which are also folded to the contours of the end plates 2 are attached to the outer surface of the support plates 2 by some suitable means; in the illustrated embodiment, staples 6 have been used. Extending around the packet of bags is a number of ties 5, which may comprise rope or some flexible material such as nylon or steel bands, or flexible metal wire, said ties being suitable for holding the elements 4 in engagement with the corners of the bags. If desired, one or more inner support plates having the same shape as the bags in their collapsed condition may be inserted between two adjacent bags in the bundle. Instead of cardboard, there may be used for the elongate edge support elements other stiff materials such as corrugated cardboard, board, paperboard, thin metal plate and wood fibreboard. WHAT WE CLAIM IS

1. A method of bundling bags which comprises forming an elongate stack of said bags; placing a bundle-stiffening plate at at least each end of the stack; placing a respective element over each longitudinally extending edge formed by the mutually adjacent corresponding corners of the bags in order to support and protect the corners of the bags; each element being of such a length as to extend over the respective corner of each of said plates; and attaching said elements and the plates to one another.

2. A method as claimed in Claim 1, wherein bundle-stiffening plates are placed internally of the stack between selected bags therein.

3. A method as claimed in Claim 1 or Claim 2, wherein the plates and said elements covering said plates are attached to one another by means of ties which are placed around said elements in the respective regions of the edges of said plates and which are thereafter tightened so as to sandwich the respective element portion between the edge of the respective plate and the respective tie.

4. A method as claimed in Claim 3, wherein at least each of the plates at the ends of said stack has a channel or recess extending circumferentially around the periphery thereof for receiving a respective one of said ties.

5. A method as claimed in Claim I or Claim 2, wherein said elements are secured to the respective end bundle-stiffening plates by means of fastener devices, and wherein at least one tie is passed aroun the stack and said elements at a location between said end bundle-stiffening plates to secure said elements against said stack.

6. A method as claimed in Claim 5, wherein the fastener devices are staples.

7. A method as claimed in any one of the preceding Claims, wherein each element covers two mutually adjacent edges of the stack and the bag edges which extend between said mutually adjacent edges.

8. A method as claimed in any one of the preceding Claims, wherein the bundle-stiffening plates are made of board or cardboard, and the comer elements are made of board, cardboard, thin metal plate or wood fibreboard.

9. A method as claimed in any one of the preceding Claims, wherein the bags are valve bags (as hereinbefore defined).

10. A method of bundling bags substantially as hereinbefore described with reference to Figures 1 to 3 or Figure 4 of the accompanying drawings.