EP2694379B1

EP2694379B1 - Method and device for unpacking a stack of flat objects packaged in an envelope of foldable packaging material

Info

Publication number: EP2694379B1
Application number: EP20120712391
Authority: EP
Inventors: Arnoldus Josephus Maria MESSING
Original assignee: DG PRESS HOLDING BV
Current assignee: DG press HoldinG BV
Priority date: 2011-04-01
Filing date: 2012-03-22
Publication date: 2015-05-13
Anticipated expiration: 2032-03-22
Also published as: NL2006521C2; WO2012134271A1; EP2694379A1

Description

The invention relates to a method for unpacking a stack of substantially flat objects packaged in an envelope of foldable packaging material, which envelope is closed at a first outer end by an edge of the packaging material which is folded back over the envelope and attached thereto at an end zone, comprising of opening the envelope at the first outer end and displacing the stack of objects in the direction of the first, opened outer end in a relative movement in relation to the envelope.
Such a method is for instance applied to unpack a stack of covers for cans, for instance beverage cans or food cans. The covers are supplied in a packaged stack to a filling station where cans are filled with for instance beverage or food, and a filled can is then closed by seam-folding a supplied cover thereon.
The packaging of the covers normally consists of a cylindrical bag of paper, foil or a laminate which is cut open in axial direction or with a helical movement. Cutting of the packaging can result in the release of dust and fragments which may find their way into the end product, which is of course undesirable in the case of food products.
Known from Netherlands patent NL 1013723 is a method for unpacking a stack of covers packaged in a sleeve wherein a portion of the sleeve located at an end surface is removed by making a cut wholly or partially around this side. According to this method a cutting line is obtained which is shorter than a cutting line in axial direction or obtained with a helical movement. As it is being made a thus obtained cutting line is nevertheless in direct contact with the underlying covers so that dust and fragments, which may find their way into the final product, may also be released during opening according to this method.
It is an object of the invention to propose a method for unpacking a stack of objects packaged in an envelope, according to which an envelope is opened, without bringing the objects during opening into contact with a cut to be made.
It has to be possible to perform such a method mechanically and in automated manner.
These objects are achieved with a method of the type specified in the preamble, wherein according to the invention opening of the envelope comprises of cutting through the folded-back edge along a cutting line extending between the end zone of the edge and the first outer end of the envelope while preserving intact the flexible material extending between the end zone and the stack.
Other than in a prior art method, only the edge of the envelope folded back over the outer end is cut through, and part of the envelope that is in direct contact with the objects packaged therein remains intact. This method provides the advantage that possibly released dust and fragments cannot come into direct contact with the packaged objects, and can for instance be suctioned away before the objects are pressed out of the envelope.
An embodiment of a method according to the invention comprises the steps of (i) receiving the packaged stack of objects between a first and second receiving member to be arranged respectively against the first end surface at the first outer end and the opposite second end surface at the second outer end, and arranging a pushing member extending at least partially along a peripheral edge of the second end surface, (ii) releasably coupling the envelope at the second outer end to the second receiving member arranged thereagainst, (iii) opening the envelope at the first outer end, and (iv) displacing the pushing member in a relative movement in the direction of the first receiving member while maintaining the distance between the first receiving member and the pushing member, in a manner and over a distance such that the stack of objects is displaced in the direction of the first, opened outer end and the stack moves wholly clear of the envelope.
Receiving the stack of packaged objects between receiving members in this way provides the advantage that the stack can be manipulated mechanically in simple and controlled manner before, during and after opening.
The invention further relates to a device for unpacking a stack of substantially flat objects packaged in an envelope of foldable packaging material, which envelope is closed at a first outer end by an edge of the packaging material which is folded back over the envelope and is attached thereto at an end zone, at least comprising opening means for opening the envelope at the first outer end, wherein the opening means comprise cutting means which are adapted to cut through the folded-back edge along a cutting line extending between the end zone of the edge and the first outer end of the envelope while preserving intact the flexible material extending between the end zone and the stack.
In an embodiment of such a device a first and second receiving member to be arranged respectively against the first end surface at the first outer end and the opposite second end surface at the second outer end are provided for the purpose of receiving the packaged stack of objects therebetween.
Another embodiment provides a pushing member to be arranged extending at least partially along a peripheral edge of the second end surface.
The pushing member preferably has in longitudinal direction of the stack of objects an opening corresponding to the outer periphery of the second receiving member.
A pushing member with such an opening provides the advantage that, prior to the envelope being opened, this pushing member can be arranged around the second receiving member in direct contact with the second end surface of the envelope and can be displaced after opening of the envelope, wherein the stack of objects is pressed out of the envelope via the opened first outer end without this resulting in the possibility of the objects tipping over or the stack being pressed in a direction obliquely of the envelope.
In an advantageous embodiment displacing means are provided for displacing the pushing member in the direction of the first receiving member in a relative movement while maintaining the distance between the first receiving member and the pushing member, in a manner and over a distance such that the stack of objects is displaced in the direction of the first, opened outer end and the stack moves wholly clear of the envelope.
In another embodiment coupling means are provided for releasably coupling the envelope at the second outer end to the second receiving member.
Using these coupling means the envelope can be coupled releasably to the second receiving member prior to the displacement of the stack by the pushing member so that the envelope is held fast by this receiving member as the stack of objects is pressed outward.
In a subsequent embodiment discharge means are provided for discharging particles released during cutting of the folded-back edge of the envelope.
The cutting means in a device according to the invention comprise for instance a knife or a laser device.
In a preferred embodiment the device is provided with sensor means for accurately determining the position of the folded-back edge of the envelope of a packaged stack received between the respective receiving members.
The invention will be elucidated hereinbelow on the basis of an exemplary embodiment, with reference to the drawings.
In the drawings

Fig. 1 is a schematic view of a packaging with a stack of round, flat objects,
Fig. 2 is a schematic view of a part of the packaging shown in Fig. 1 received in an unpacking station,
Fig. 3a-3c are schematic views of the first outer end of the packaging shown in fig. 2 in successive phases of opening and unpacking, and
Fig. 4a-4c show schematic views of the second outer end of the packaging shown in Fig. 2 in successive phases of opening and unpacking.

Corresponding components are designated in the figures with the same reference numerals.
Fig. 1 is a schematic perspective view of an envelope 1, for instance a paper bag, in which a stack of covers 13 (shown in Fig. 3b, 3c) is packaged and which is closed at the left-hand outer end 2 by an edge 3 which is folded back over envelope 1 and attached thereto at an end zone 4, for instance with adhesive or tape.
Fig. 2 is a schematic perspective view of a part of the envelope 1 shown in Fig. 1 received in an unpacking station, a mandrel 5 of which is shown arranged against the first outer end 2 of packaging 1, and of which a knife 6 is carried in a relative displacement to the correct position relative to envelope 1 by means of a control circuit (not shown). The control circuit, which is coupled to a position sensor 7 which scans the folded-back edge 3, defines a cutting line 8 which lies between the left-hand end surface 2 and end zone 4 of edge 3. Mandrel 5 forms a first receiving member which is arranged initially against the outer side of packaging 1. A second receiving member 9 is arranged on the right-hand side (shown in Fig. 4a-4c). By rotating packaging 1 in the direction as according to arrow 10 using receiving members 5, 9 and placing knife 6 on cutting line 8 using the control circuit, the folded-back edge 3 is cut through along cutting line 8, wherein the part of envelope 1 located under edge 3 remains intact.
Fig. 3a shows the left-hand part of the envelope 1 shown in fig. 2 immediately after the folded-back edge 3 has been cut through and prior to the packaged stack of covers being pushed out of envelope 1. Fig. 3a also shows a guide rail 11 for a pushing member 12 (shown in Fig. 4a).
Fig. 4a shows the right-hand part of the envelope 1 shown in Fig. 2 in the same situation as in Fig. 3a. Shown are a second receiving member 9 which is arranged against the right-hand end surface of envelope 1 and an annular pushing member 12 arranged against the peripheral edge of this right-hand end surface, wherein the opening enclosed by the annular form corresponds to the outer periphery of the right-hand receiving member 9. The right-hand receiving member 9 is provided with suction nozzles and a vacuum connection (not shown), using which the right-hand outer end of envelope 1 is coupled releasably to the right-hand receiving member 9.
Fig. 4b shows the right-hand part of envelope 1 in a situation where the right-hand receiving member 9 is displaced through a relatively short distance to the right while carrying with it the envelope 1, which is pulled through pushing member 12.
Fig. 3b shows the left-hand part in the situation corresponding to fig. 4b. As a result of the short displacement of the right-hand receiving member 9, a part of envelope 1, which has been cut free of folded-back edge 3, is pulled between the packaged covers 13 and a left-hand receiving member 5, wherein the packaged covers 13 have become partially visible.
Fig. 3c shows the left-hand part of envelope 1 in a situation where the stack of covers 13 has been pushed a determined distance out of envelope 1, and the left-hand receiving member 5 is in direct contact with the stack of covers 13.
Fig. 4c shows the right-hand part of envelope 1 in the same situation as in fig. 3c. In this situation pushing member 12 has displaced along guide rail 11 in the direction of the opened left-hand end surface and the right-hand receiving member 9 has been displaced further to the right, wherein the distance between pushing member 12 and the right-hand receiving member 9 corresponds to the determined distance in fig. 3c over which covers 13 have been pushed out of envelope 1.
Once the stack of covers has been pushed completely out of the envelope it is held in position by the pushing member and the left-hand receiving member for transport to a filling machine where the covers are arranged on the respective filled cans, and the empty envelope can be pulled away by the right-hand receiving member and then released therefrom for further discharge.

Claims

Method for unpacking a stack of substantially flat objects (13) packaged in an envelope (1) of foldable packaging material, which envelope (1) is closed at a first outer end (2) by an edge (3) of the packaging material which is folded back over the envelope (1) and attached thereto at an end zone (4), comprising of opening the envelope (1) at the first outer end (2) and displacing the stack of objects (13) in the direction of the first, opened outer end (2) in a relative movement in relation to the envelope (1), wherein opening of the envelope (1) comprises of cutting through the folded-back edge (3) along a cutting line (8) extending between the end zone (4) of the edge (3) and the first outer end (2) of the envelope (1) while preserving intact the flexible material extending between the end zone (4) and the stack (13).
Method as claimed in claim 1, characterized by the steps of
(i) receiving the packaged stack of objects (13) between a first (5) and second receiving member (9) to be arranged respectively against the first end surface (2) at the first outer end and the opposite second end surface at the second outer end, and arranging a pushing member (12) extending at least partially along a peripheral edge of the second end surface,

(ii) releasably coupling the envelope (1) at the second outer end to the second receiving member (9) arranged thereagainst,

(iii) opening the envelope (1) at the first outer end (2), and

(iv) displacing the pushing member (12) in a relative movement in the direction of the first receiving member (5) while maintaining the distance between the first receiving member (5) and the pushing member (12), in a manner and over a distance such that the stack of objects (13) is displaced in the direction of the first, opened outer end (2) and the stack (13) moves wholly clear of the envelope (1).
Device for unpacking a stack of substantially flat objects (13) packaged in an envelope (1) of foldable packaging material, which envelope (1) is closed at a first outer end (2) by an edge (3) of the packaging material which is folded back over the envelope (1) and is attached thereto at an end zone (4), at least comprising opening means (6, 7) for opening the envelope (1) at the first outer end (2), characterized in that the opening means comprise cutting means (6) which are adapted to cut through the folded-back edge (3) along a cutting line (8) extending between the end zone (4) of the edge (3) and the first outer end (2) of the envelope (1) while preserving intact the flexible material extending between the end zone (4) and the stack (13).
Device as claimed in claim 3, characterized in that a first (5) and second receiving member (9) to be arranged respectively against the first end surface (2) at the first outer end and the opposite second end surface at the second outer end are provided for the purpose of receiving the packaged stack of objects (13) therebetween.
Device as claimed in any of the claims 3-4, characterized in that a pushing member (12) to be arranged extending at least partially along a peripheral edge of the second end surface is provided.
Device as claimed in claim 5, characterized in that the pushing member (12) has in longitudinal direction of the stack of objects (13) an opening corresponding to the outer periphery of the second receiving member (9).
Device as claimed in any of the claims 5-6, characterized in that displacing means (11) are provided for displacing the pushing member (12) in the direction of the first receiving member (5) in a relative movement while maintaining the distance between the first receiving member (5) and the pushing member (12), in a manner and over a distance such that the stack of objects (13) is displaced in the direction of the first, opened outer end (2) and the stack (13) moves wholly clear of the envelope (1).
Device as claimed in any of the claims 3-7, characterized in that coupling means are provided for releasably coupling the envelope (1) at the second outer end to the second receiving member (9).
Device as claimed in any of the claims 3-8, characterized in that discharge means are provided for discharging particles released during cutting of the folded-back edge (3) of the envelope (1).
Device as claimed in any of the claims 3-9, characterized in that the cutting means comprise a knife (6).
Device as claimed in any of the claims 3-9, characterized in that the cutting means comprise a laser device.
Device as claimed in any of the claims 4-11, characterized in that it is provided with sensor means (7) for determining the position of the folded-back edge (3) of the envelope (1) of a packaged stack (13) received between the respective receiving members (5, 9).