Device and method for wrapping container groups

Abstract

A machine that forms groups of containers by wrapping containers in a film blank includes an adhesive applicator that is arranged along a film-transporter for applying adhesive onto an inner side of the film blank and along longitudinal side edges of the film blank before the containers are wrapped. The placement of the adhesive avoids distortion of images or text that are printed on the film blank due to shrinkage.

Claims

1. A method comprising: producing a group of containers, said group having a front side and a rear side, wherein producing said group comprises transporting a film blank on a film conveyor of a first film-transporter from a cutter onto a transport plane, said film blank having front and rear motifs for placement on said front side and said rear side, respectively, during transport of said film blank and prior to said film blank having reached said transport plane, applying adhesive onto first and second longitudinal side edges of an inner side of said film blank, wherein applying said adhesive comprises, for each of said motifs, applying said adhesive at first and second pairs of application points on said first and second longitudinal side edges, respectively, wrapping said containers as said containers are being transported on a group conveyor, thereby forming said group, and after having wrapped said containers, bonding said longitudinal side edges of said film blank to face sides of said group such that said front and rear motifs are on said front and rear sides of said group, respectively, wherein said film blank is made from a film of shrink film, foldable paper, or card material.

2. The method of claim 1, wherein bonding said longitudinal side edges comprise pressing said longitudinal side edges, which project away from said group, towards said face sides.

3. The method of claim 1, wherein applying said adhesive comprises applying points of adhesive.

4. The method of claim 1, wherein applying said adhesive comprises applying at least one adhesive point to each longitudinal side edge of said film blank per front side and rear side of said group.

5. The method of claim 1, wherein applying said adhesive comprises applying at least two adhesive points on each longitudinal side edge of said film blank per front side and rear side of said group.

6. The method of claim 1, further comprising selecting said adhesive to be a hot-melt adhesive.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) The invention is described in greater detail hereinafter on the basis of exemplary embodiments. The Figures show:

(2) FIG. 1 shows a device for wrapping containers to form a group.

(3) FIGS. 2a and 2b show different views of a group.

(4) FIG. 3a shows a face-side view of a group.

(5) FIG. 3b shows a front view of the group shown in FIG. 3a.

(6) FIG. 3c shows an alternative embodiment of a group.

(7) FIG. 4 shows a film blank with regions drawn for adhesive agent points and motifs.

DETAILED DESCRIPTION

(8) FIG. 1 shows a packaging machine 1 for wrapping a group 2 of containers 3 with a film 4. Each group 2 is a container group that is formed by wrapping containers 3 with a film blank 15, shown in FIG. 2a, that is made from the film 4. Each group 2 has corner containers 3a, as seen in FIG. 3a.

(9) As shown in FIG. 2a and FIG. 2b, a container group 2 has a face side 26 and a front side 22. The face side 26 has a shrinkage hole 27 formed therein. The front side 22 has a motif 28 printed thereon.

(10) Referring back to FIG. 1, the packaging machine 1 includes a wrapper 5 and a group conveyor 6 that runs along a transport plane TE. The wrapper 5 is a folding and/or wrapping device. The group conveyor 6 is a packaging-group transport-device. The packaging machine 1 also includes at least one wrap bar 7 that moves on a track 8 around the group conveyor 6 and around whatever groups 2 are being transported on the group conveyor 6. The illustrated embodiment shows three such wrap bars 7.

(11) The packaging machine 1 further comprises an intake transporter 9 for receiving containers 3 onto the group conveyor 6 so that they can be formed into a group 2. The packaging machine 1 also includes a discharge transporter 11 for receiving the group 2 that has been formed by wrapping the containers 3 with a film blank 15. The discharge transporter 11 transports the group 2, with a front side 22 thereof leading, along a group-transport direction LR to a shrinking device. The shrinking device has been omitted for clarity.

(12) The packaging machine 1 also includes a first film-transporter T1 and a second film-transporter T2. As shown in FIG. 1, the first film-transporter T1, which is directly beneath the intake transporter 9, runs from a film dispenser to the transport plane TE. The second film-transport segment T2 connects to the first transport segment T1 and extends to the end of the group conveyor 6.

(13) The film 4 that comes from the dispensing unit moves into a cutter 12 that lies below the transport plane TE. The cutter 12 separates the film 4 to form the film blanks 15.

(14) The first film-transport segment T1 includes a post-cutter segment T1.1 that extends along a film-conveying direction LRF upwards from the cutter 12 towards the transport plane TE.

(15) The first transport segment T1 includes a film conveyor 13 that begins at the cutting station 12 and runs past an adhesive applicator 14, which applies adhesive 17 onto longitudinal side edges 29 of the film blank 15, as shown in FIG. 4. The film conveyor 13 then proceeds on to the transport plane TE.

(16) The adhesive applicator 14 comprises two adhesive agent heads 14a, 14b for placing adhesive at application points 19. As shown in FIG. 3a, the application points 19 are spaced apart on the inner side 18 of the film web 15 along the longitudinal side edges 29. In some embodiments, application of the adhesive at the application points 19 takes place at the film conveyor's end region 20.

(17) In some embodiments, the adhesive applicator 14 has only one adhesive head. In such cases, the head moves from one place to another to apply adhesive one point at a time. Among these embodiments are those in which the head moves transverse to the film-conveying direction LRF. In other embodiments, the head moves in a direction along the film-conveying direction LRF. In still other embodiments, the adhesive applicator 14 has more than two heads to be provided, which are likewise arranged such as to be movable or not movable as required.

(18) In operation, the cutter 12 forms a film blank 15. The film conveyor 13, which is implemented as a vacuum table, brings the film blank 15 to the group conveyor 6. During the transport, the film blank 15 is conveyed past the adhesive applicator 14 at the end region 20. The adhesive applicator's heads apply adhesive agent onto the longitudinal side edges 29 of the film blank 15. A suitable adhesive is one that can be sprayed or one that can flow. A particularly useful adhesive agent is a hot melt adhesive agent.

(19) Containers 3 that are to become part of a group 2 and that are delivered by the intake transporter 9 are arranged on a front edge 16 of the film blank 15. The wrap bar 7 rises from beneath the transport plane TE through a gap between the group conveyor 6 and the intake transporter 9. As it does so, it engages an outer side 21 of the film blank 15. As the wrap bar 7 climbs, it brings the outer side 21 with it.

(20) The wrap bar 7 moves faster than the group conveyor 6. As a result, the wrap bar 7 is able to overtake the containers 3. As the wrap bar 7 descends back towards the transport plane TE, it wraps the outer side 21 of the film blank 15 around the containers 3, thus forming the group 2. Upon reaching the conveyor's end, the wrap bar 7 descends below the transport plane TE through a gap between the group conveyor 6 and the discharge transporter 11.

(21) The group 2, which continues to move, moves onto the rear edge 30 of the film blank 15. Accordingly, the front side 22, the rear side 23, and the upper and under sides 24, 25 of the group are covered by the film blank 15. The group 2 is therefore wrapped on four sides. A lateral film projection remains over the face sides 26 with the application points 19 thereon.

(22) A presser or stroker acts on the film projection so that it moves towards the group's face sides 26. This causes the adhesive at the application points 19 to bond to the corner containers 3a. The film blank 15 is then shrunken into place in a shrinking device.

(23) FIGS. 2a and 2b show a group 2 with individual containers 3, which are wrapped or enveloped with a film blank 15. The film blank 15 is already shrunk, such that a shrinkage hole 27 is formed on the face side 26. It is apparent that the motif 28 applied on the front side 22 is distorted due to the shrinkage process of the film material.

(24) FIG. 3a shows a first embodiment of a group 2 produced in accordance with the method and on the device with a film blank 15 of shrink film bonded to it as seen from the face side 26. The illustrated application points 19 bond the longitudinal side edges 29 with the group's corner containers 3a to the face sides 26 of the group 2. The application points 19 have been applied at a distance from one another such that two application points 19 are arranged at the respective longitudinal side edge 29 aligned with the front side and the rear side to fix the film blank 15 on the face side 26.

(25) FIG. 3b shows a front view of the group 2 shown in FIG. 3a. For better understanding of the effect of the application points 19, the application points 19 are likewise represented. These, however, are located on the face side 26 of the group 2. Because the film blank 15 has been bonded on the face sides 26, the motif 28 is undistorted.

(26) FIG. 3c likewise shows a front view of an alternative group 2 in which the film blank 15 is bonded at the front side 22 as well as at the rear side 23 at each longitudinal side edge 29 by only one application points 19 on the face side 26. Only to promote understanding, the application points 19 are drawn in the front view. However, they are actually present on the face side 26.

(27) FIG. 4 shows schematically, in one view, an angled film blank 15 of a shrink film for wrapping a group 2, with regions drawn in for the application points 19, motifs 28, and the later position of the containers 3 in the film blank 15.

(28) The film blank 15 has two motifs 28, which in the wrapped state are positioned on the front side 22 and rear side 2 of the group 2. Application points 19 are located on both of the longitudinal side edges 29. For each motif 28, in each case two application points 19 are provided per longitudinal side edge 29.

(29) The four application points 19 around a motif are arranged at equal distances from the motif 28. This suppresses even slight distortions of the motif 28.

(30) For the bonding of the front edge 16 of the film blank 15 to the base of the group 2 or to the base of the containers 3, two application points 19 are provided in the region of the front edge 16. As an alternative, it is also possible, for example, for application points 19 to be provided at the rear edge 30, opposite the front edge 16, in order to bond the rear edge 30 to the front edge 16.

(31) In the figures and in the foregoing explanations, the packaging machine 1 and the method have been illustrated and described primarily for the adhesive bonding of web blanks made of film (plastic, shrink film). However, the same techniques are applicable to foldable paper and/or card materials, can also be provided for, wherein in this case, for the adhesive agent application, a device can be provided which is very largely identical in location and structure to the adhesive agent application device 14. The wrapper 5 and the elements located downstream are provided for in an analogous manner, although they are to be adapted in a manner known to the person skilled in the art for the wrapping of containers 4 with the foldable paper and/or card blanks.

(32) As already mentioned, the adhesive applicator 14 is ideally suited for the application of hot-melt adhesive that comes out through one or more heads of the adhesive applicator 14. With one embodiment, not represented in any greater detail, at least two adhesive heads are provided and arranged on opposing sides of the film conveyor 13. Associated devices for the application of a hot or melt adhesive, such as storage containers, heating devices, pumps etc. are not shown.