Package, Packaging Apparatus, and Method of Making Packages
The present invention relates to a package, a packaging apparatus and to a method of making packages.
It is known to employ vertical form, fill, and seal (FFS) packaging apparatus to produce packages, in the form of bags, pillow packs or pouches of products, such as snack foods. A tubular film, having been formed from a roll of packaging film of heat sealable plastic material which has been longitudinally sealed, is fed intermittently through a jaw device. The film forms a flattened tube at the jaw device. The jaw device forms a pair of vertically spaced hermetic heat seals extending transversely across the tube, the seals being located between vertically adjacent packages. The jaw device also cuts through a middle portion, located between the hermetic seals, extending across the tube which separates a lower sealed package containing the packaged product from an upper unsealed package.
In this way, a lower hermetic seal forms the upper seal of the lower package, and an upper hermetic seal forms the lower seal of the upper package. The upper package is then filled with product, the tube is advanced downwardly through the jaw device, and then the cycle is repeated when the upper edge of the upper package, and the lower edge of the following package, is disposed between the jaws of the jaw device.
Correspondingly, a horizontally oriented form, fill, and seal packaging apparatus is also known, in which the packaging material and the products are fed horizontally rather than vertically.
It is known in particular to employ such form, fill, and seal packaging apparatus to produce primary packages, which contain the packaged product, as well as secondary packages, which contain a plurality of primary packages. In the snack food industry, it is well known to packages snack foods in primary package bags, which hermetically seal the product therein, and for a plurality of the primary package bags to be packaged in a "multipack" secondary package, both primary and secondary packages being formed sequentially by respective form, fill, and seal packaging apparatus.
In the packaging industry there is a general need to reduce packaging costs and also to reduce the environmental impact of the packaging. The primary and secondary packaging needs to be sealed in order securely to contain the packaged products. The secondary packaging for snack food products typically comprises polymeric film material, for example of a heat sealable polymer, or paper which is adhered by an adhesive layer or a heat sealable polymer coating, in order for such seals to be formed. The requirement for such polymers and adhesive to form the packaging not only increases production cost and complexity, but also produces a multi-material package which is difficult to recycle efficiently. Also, when heat sealing is used this increases the energy requirement of the production process, which increases the carbon footprint, i.e. carbon dioxide emissions, of the packaging.
Accordingly, there is a need in the ait for a package, a packaging apparatus, and a method of making packages, which can permit the cost and complexity of the packaging material to be reduced, together with the associated carbon footprint, while still achieving effective seals in the package.
There is a further need in the art for a secondary package, particularly for snack foods, which has lower manufacturing cost and improved recyclability as compared to known secondary packages.
The present invention aims at least partially to meet these needs.
The present invention accordingly provides a package comprising a secondary packaging defining a central cavity containing a plurality of primary packaged products, the package comprising a folded layer of paper and having at least one mechanical seal at which plural plies of the layer of paper are mechanically crimped together, the mechanical crimping being the sole joining mechanism between the adjacent sealed plies.
The present invention further provides a packaging apparatus for packaging at least one product within a package, the packaging apparatus comprising a form, fill and seal machine including at least one crimping device adapted to mechanically crimp together
plural plies of a layer of paper to form at least one mechanical seal in a package, the mechanical crimping being the sole joining mechanism between the adjacent sealed plies.
The present invention further provides a method of making packages, the method comprising the steps of:
a. providing a folded layer of paper;
b. conveying the folded layer of paper through a form, fill and seal machine; and
c. mechanically crimping together plural plies of the paper in the form, fill and seal machine to form at least one mechanical seal in a package, at which seal plural plies of the layer of paper are mechanically crimped together, the mechanical crimping being the sole joining mechanism between the adjacent sealed plies.
The invention is predicated on the finding by the present inventors that mechanical crimp seals can be used in packaging to provide sealed paper packages that are entirely free of adhesive or heat sealed materials. This increases the recyclability of the packaging and reduces the carbon footprint of the packaging. The packages of the invention have particular application in the manufacture of secondary packaging, in the form of multi- packs, for snack food products. Such secondary packaging must be sufficiently robust to provide a secure packaging for the primary packs from the time of manufacture, through distribution, retail sale and final use by the consumer, but the seals of the secondary packaging do not require to be hermetic, since such hermetic seals for protecting the product against environmental degradation are already present in the primary packaging. The package of the invention may also be used for packaging a wide range of other products, as primary or secondary packaging.
In this specification, the term "primary packaging" means the packaging containing the actual product to be used or consumed by the user, such as a snack food, and the term "secondary packaging" means the packaging which contains, directly or indirectly, one or more primary packaged products, with the term "secondary packaging" encompassing
"tertiary packaging", which may provide a further outer package for the secondary packaging.
Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:
Figure 1 is a schematic perspective view of a package in accordance with an embodiment of the present invention;
Figure 2 is a schematic side view of a packaging apparatus in accordance with an embodiment of the present invention; and
Figure 3 is a schematic enlarged side perspective view of a crimping device in the packaging apparatus of Figure 2.
Figure 1 illustrates a package in accordance with an embodiment of the present invention. The package 2 comprises a folded layer 4 of paper defining a central cavity 6 containing at least one packaged product 8 (shown in phantom). The thickness of the paper is exaggerated for clarity of illustration. The package 2 has at least one mechanical seal 10 at which plural plies 12, 13, 14 of the layer 4 of paper are mechanically crimped together. The mechanical crimping is the sole joining mechanism between the adjacent sealed plies 12, 13, 14. Preferably, the mechanical crimping comprises at least one mechanical seal which in turn comprises an embossed mechanical interlock between adjacent paper plies. Optionally each mechanical seal consists of an embossed mechanical interlock extending in a single plane without any folding back of any of the paper plies. The embossed mechanical interlock provides the sole joining mechanism preventing separation of the paper plies.
The package 2 is pillow-shaped and has opposed ends 16, 18. Each end 16, 18 has a respective transverse mechanical seal 20, 22. A longitudinal mechanical seal 24 extends longitudinally between the transverse mechanical seals 20, 22.
In a preferred embodiment, the package 2 comprises a secondary packaging containing a plurality of snack food packs 8. The paper is of a type typically used in packaging and
2 2 optionally has an areal weight of from 25 to 125 g/m ' optionally from 50 to 100 g/m , optionally from 60 to 80 g/m .
In the most preferred embodiment, the package 2 consists solely of a single folded layer 4 of paper defining the central cavity 6. The paper may however optionally include at least one of a hydrophobic material, such as a coating of clay material, such as china clay, to provide a water repellent surface of the package and printing. The hydrophobic material may be an exterior coating. However, no heat seal polymer or adhesive layer is present. The paper may also include at least one machine glazed surface, produced by calendaring the paper surface under pressure.
Each mechanical seal 20, 22, 24 comprises an embossed mechanical interlock between adjacent paper plies 12, 13, 14. The embossed mechanical interlock typically comprises a succession of alternating concave and convex portions 26, 28 inclined to the longitudinal direction of the mechanical seal. The pattern, spacing and dimensions of the concave and convex portions 26, 28 may be different for the transverse mechanical seals 20, 22 and the longitudinal mechanical seal 24. The embossed mechanical interlock complementarily shapes the adjacent paper plies 12, 13, 14 in the thickness direction without puncturing the paper. However, such puncturing may optionally be present to provide an enhanced mechanical interlock.
The mechanical seal 20, 22, 24 may comprise a selected one of a variety of seal configurations. The seal may include a single series of alternating concave and convex portions 26, 28. These alternating concave and convex portions 26, 28 may have any selected inclination to the longitudinal direction of the mechanical seal 20, 22, 24. The concave and convex portions 26, 28 may have a desired length and spacing.
As shown in the illustrated embodiment of Figure 1 , at least one of the mechanical seals, such as the transverse seals 20, 22, may optionally comprise a pair of parallel spaced seal portions 32, 34 each extending in the longitudinal direction of the mechanical seal. This
provision of two spaced seal portions 32, 34 can enhance the shear strength of the seal. The longitudinal seal 24 may optionally have a similar structure.
Figure 2 is a schematic side view of a packaging apparatus in accordance with an embodiment of the present invention which can be used to make the package 2 of Figure 1. The packaging apparatus 40 is adapted to package at least one product 8 within the package 2, and typically comprises a form, fill and seal machine 40. The packaging apparatus 40 includes at least one crimping device 42, 44 adapted to mechanically crimp together, under applied pressure, plural plies of the layer 4 of paper to form the mechanical seal 20, 22, 24, the mechanical crimping being the sole joining mechanism between the adjacent sealed plies 12, 13, 14.
A conveying device 46 conveys the layer 4 of paper through the machine 40. The layer 4 of paper is folded and comprises a flattened tube 48. A transverse crimping device 42 comprises opposed first and second crimping portions 50, 52. The first and second crimping portions 50, 52 may comprise a pair of opposed first and second rotary elements 58, 60. Each rotary element 58, 60 has an outer crimping surface 62, 64 complementarily interlocking with the opposite rotary element 58, 60. The rotary elements 58, 60 may be composed of metal.
As shown in Figure 3, each of the first and second crimping portions 50, 52 includes upstream and downstream crimping regions 51a, 51b; 53a, 53b which are parallel and separated by a respective gap 54a, 54b. A transversely oriented knife element 56 is located in the gap 54a of the upstream and downstream crimping regions 51a, 51b of the first crimping portion 50. A transversely oriented anvil 57 is located in the gap 54b of the upstream and downstream crimping regions 53a, 53b of the second crimping portion 52.
The first and second crimping portions 50, 52, knife element 56 and anvil 57 extend transverse to a longitudinal direction L of the form, fill and seal machine 40.
In a manner similar to that used in known form, fill and seal machines, the flattened tube 48 is intermittently fed longitudinally through the machine 40 by the conveying device
46. The feeding is in an indexed manner, so that the required portion of the flattened tube 48 to be sealed is located at the transverse crimping device 42. The first and second crimping portions 50, 52 simultaneously form first and second crimping regions 66, 68 which are correspondingly parallel. In addition, simultaneously with their formation, the first and second crimping regions 66, 68 are separated by a cut made by the knife element 56 which separates adjacent packages 2. The knife element 56 is urged under pressure against the anvil 57 to cut through the folded paper of the flattened tube 48, trapped between the knife element 56 and the anvil 47, by a pressured crush-cutting action. The upper package 2a, having the first crimping region 66 as a lower seal thereof, is retained within the machine 40 and the lower package 2b, having the second crimping region 68 as an upper seal thereof, is released from the machine 40.
The illustrated embodiment employs a rotary motion, which may be a continuous rotary motion or an oscillatory rotary motion, for synchronously moving the first and second crimping portions 50, 52 of the transverse crimping device 42 into and out of engagement with the flattened tube 48. Typically, the first and second crimping portions 50, 52 both rotate in phase and in opposite rotational directions as shown by the arrows in Figure 2 so that the first and second crimping portions 50, 52 crimp, and the knife element 56 acting against the anvil 57 cuts, the flattened tube 48 of paper centrally located therebetween.
During the crimping operation, the first and second crimping portions 50, 52 are rotated into engagement with the flattened tube 48 to perform the crimping operation. The knife element 56 separates adjacent packages 2. Thereafter, the first and second crimping portions 50, 52 are rotated out of engagement with the flattened tube 48, which is then advanced longitudinally for the next cycle. The first and second crimping portions 50, 52 are laterally separated by a distance sufficient to permit the next filled package 2 to be conveyed therebetween.
The first and second crimping portions 50, 52 are each rotated about a respective axis X, Y which is orthogonal to the longitudinal direction L of the flattened tube 48.
In alternative embodiments, the first and second crimping portions 50, 52 may not be rotated but are be reciprocated translationally as shown by the arrows T in Figure 2.
In a subsequent cycle, the flattened tube 48 is again intermittently fed longitudinally through the machine 40 by the conveying device 46 in an indexed manner, so that the required upstream portion of the flattened tube 48 to be sealed is located at the transverse crimping device 42. The crimping and cutting operation is repeated to form the next package 2a. Accordingly, the opposed ends 16, 18 of each pillow-shaped package 2 are successively crimped.
Subsequent to each crimping and cutting operation, the endmost package 2 still attached to the flattened tube 48 is filled with the product 8, and optionally weighed.
The longitudinal crimping device 44 is adapted to form the longitudinal mechanical seal 24 extending between the transverse mechanical seals 20, 22 in the pillow-shaped package 2. The longitudinal crimping device 44 comprises third and fourth crimping portions 70, 72 which are adapted continuously to form the longitudinal mechanical seal 24 which extends in a longitudinal direction of the form, fill and seal machine 40. The third and fourth crimping portions 70, 72 comprise a pair of opposed third and fourth rotary elements 74, 76, each rotary element 74, 76 having an outer crimping surface 78, 80 complementarily interlocking with the opposite rotary element 78, 80. The third and fourth crimping portions 70, 72 are located upstream, in a conveying direction of the layer 4 of paper through the form, fill and seal machine 40, of the first and second crimping portions 50, 52. The rotary elements 74, 76 may be composed of metal.
Each crimping device 42, 44 is adapted to form, under applied pressure, an embossed mechanical interlock between the adjacent paper plies 12, 13, 14, and the mechanical interlock comprises a succession of alternating concave and convex portions inclined to the longitudinal direction of the mechanical seal. Typically, the embossed mechanical interlock complementarily shapes the adjacent paper plies 12, 13, 14 without puncturing the paper.
As explained above with respect to the package 2 of Figure 1, at least one of the crimping devices 42, 44 is adapted to form at least one of the mechanical seals which comprises a pair of parallel spaced seal portions, each extending in a longitudinal direction of the mechanical seal.
Although the embodiment illustrated in the Figures is a vertical form, fill and seal machine, the invention may also be used in a horizontal form, fill and seal machine.
Furthermore, although the package of the embodiment illustrated in the Figures is a pillow-pack, the package of the invention may have other shapes and configurations incorporating at least mechanically crimped seal, for example a pouch or bag. Also, some or all of the crimping may be effected by other than a form, fill and seal machine, for example in a crimping device off-line from the filling device.
Yet further, other crimping configurations may be employed to provide the desired mechanical interlock.
Other modifications to the embodiments of the invention disclosed herein will be apparent to those skilled in the art.