EP2442971A2

EP2442971A2 - Apparatus and method for folding semi - rigid sheet material

Info

Publication number: EP2442971A2
Application number: EP10755205A
Authority: EP
Inventors: David Joseph Drake; Anthony John Lukasiewicz; Hendrik Fredrik Stoltz; Gert Lourens Jacobus Venter
Original assignee: Elopak Systems AG
Current assignee: Elopak Systems AG
Priority date: 2009-06-18
Filing date: 2010-06-18
Publication date: 2012-04-25
Also published as: WO2010146375A2; WO2010146375A3

Abstract

Apparatus for folding substantially rectangular bottom end closure panels of a carton sleeve (20) of semi-rigid sheet material in forming a carton comprises two pairs of arms (28) oscillatable towards and away from one another relative to the panels, two jaws (34) and (36) pivotally mounted on the respective arms (28) and whereof the axes of turning (37) are oscillatable with the arms (28) relative to the panels and which are applicable in substantially parallel manners to the respective panels to be folded relative to respective other panels of the carton sleeve (20) which are backed up by a mandrel.

Description

APPARATUS AND METHOD

The invention relates generally to apparatus for and a method of folding sheet material in forming a container from that material, more particularly to turntable jaws for use in forming end closures of containers.

In the field of packaging, thermoplastics-coated paperboard carton sleeves are placed on mandrels which move along a path and then have end zones of their coatings heated to a tacky consistency. The carton sleeves and mandrels move along the path into a folding zone where folds in the carton sleeves are formed at those end zones by pivoting jaws that engage the 'carton sleeve to fold the sleeve on score lines preformed on the sleeve. One problem encountered is that inaccurate folds on the carton sleeves sometimes occur. One of the problems with current turnable pre-sealing jaws is that the jaws when folding make angled contact with the panels of the carton sleeves. It is desirable to have the initial contact with the carton board to be as close to parallel to the carton board as possible to ensure that the carton sleeve end closure panels fold properly. In order for the jaws to contact as closely to parallel of an angle as possible, the jaws must be placed in close proximity to the panels prior to folding. This close placement creates further problems because placement of the jaws close to the panels can cause contact between the mandrels and the jaws and possibly other components as the mandrels move in and out of position. Thus it is desirable to develop presealer arrangements that allow for the close placement of jaws while preventing damage to the mandrels and other components in the folding area.

It is known during folding to hold the carton sleeves against the mandrels by means of oppositely arranged clamping members reciprocated by respective piston-and-cylinder devices.

According to a first aspect of the present invention, there is provided apparatus for folding semi-rigid sheet material in forming a container from said sheet material, comprising ' a mounting device arranged to be oscillatable relative to said sheet material, a jaw pivotally mounted on said mounting device and whereof the axis of turning is oscillatable with said mounting device relative to said sheet material and which is applicable in a substantially parallel manner to a part of said sheet material to be folded relative to another part of said sheet material.

According to a second aspect of the present invention, there is provided apparatus for folding semi-rigid sheet material in forming a container from said sheet material, comprising first and second mounting devices arranged to be oscillatable towards and away from one another relative to said sheet material, first and second jaws pivotally mounted on the respective mounting devices and whereof the axes of turning are reciprocable with said mounting devices relative to said sheet material and which are applicable in substantially parallel manners to respective parts of said sheet material to be folded relative to respective other parts of said sheet material. The apparatus may further comprise first and second fingers oscillatable towards and away from one another to fold inwards respective further parts of the sheet material which are among those respective parts of the sheet material to be folded relative to the other parts of the sheet material.

The mounting devices may be oscillatable also to hold the sheet material during the folding and to release the sheet material after the folding.

The or each mounting device may comprise a pivotable arm turnable relative to a support. The apparatus may further comprise a mandrel for supporting the sheet material and for backing-up the other part (S) thereof.

The or each mounting device may carry a diverter arranged to steer the mounting device (s) and the jaw(s) out of a path of movement of the mandrel.

The or each diverter, which may be a ramp, may be arranged to steer by being displaced by the mandrel.

The apparatus would generally be in the form of a pre- sealing apparatus.

According to a third aspect of the present invention, there is provided a method of forming a container of semirigid sheet material, including supporting said sheet material, applying a pivotably mounted jaw in a substantially parallel manner to a part of said sheet material, and turning said jaw, while said jaw remains substantially parallelly applied to said part, to fold said part relative to another part of said sheet material.

According to a fourth aspect of the present invention, there is provided a method of forming a container of semirigid sheet material, including supporting said sheet material, applying first and second pivotally mounted jaws in respective substantially parallel manners to respective parts of said sheet material, and turning said jaws, while said jaws remain substantially parallelly applied to said respective parts, to fold said respective parts relative to respective other parts of said sheet material.

The method may further include folding inwards respective further parts of the sheet material which are among those respective parts of the sheet material to be folded relative to the other parts of the sheet material.

The method may further comprise backing-up the other part(s) of the sheet material with a mandrel which, prior to the turning of the jaw(s), would be brought into a location opposite to the jaw(s) . The method may further include, between the bringing of the mandrel into that location and the inward turning of the jaw(s), displacing an axis of turning of the or each jaw inwardly to adjacent to the sheet material at end edge of the mandrel.

The method may further include, during the bringing of the mandrel into that location, displacing the jaw(s) outwardly under the action of the mandrel.

The method may further comprise, prior to the turning of the jaw(s) inwards, pressing against the sheet material to hold the sheet material in position.

The sheet material may comprise a laminate comprised of an intermediate layer of cellulosic material and innermost and outermost layers of thermoplastics. Owing to the first to fourth aspects of the invention, it is possible reliably to produce accurately appropriate folding of the sheet material.

According to a fifth aspect of the present invention there is provided apparatus for folding sheet material in forming a container from said sheet material, comprising first and second holding devices arranged to be oscillatable towards and away from each other relative to said sheet material to hold said sheet material in a desired position and to release said sheet material therefrom, and a drive device common to and mechanically connected to said first and second holding devices for operating the same.

The holding devices may comprise respective first and second oscillatable arms.

The apparatus may further comprise first and second jaws pivotally mounted upon the respective first and second holding devices and serving to fold respective parts of the sheet material relative to respective other parts thereof.

Owing to the fifth aspect of the invention, it is possible to produce in a relatively simple manner reliably symmetrical holding of the sheet material. The first to fifth aspects of the invention may be employed in top or bottom pre-breaking and/or sealing of a carton sleeve, with the sleeve being closely received, insofar as its cross-section is concerned, over a mandrel or in a pocket, or, if feasible, in top pre-breaking and/or sealing of a filled, bottom-closed and -sealed carton.

A preferred embodiment of the present invention comprises a presealer arrangement for a carton folding system that folds and seals carton sleeves. The presealer arrangement has a frame member that is positioned relative to a folding zone. A conveyor or path extends through the folding zone so that one or more mandrels having one or more carton sleeves supported thereon move into and out of the folding zone. Two or more arms are pivotally connected to the frame member and turn between a hold condition, where the two or more arms have been turned towards each other and a release condition, where the two or more arms have been turned away from each other and thus away from the folding zone. Pivotally connected to the two or more arms are two or more jaws that are movable between a retracted condition and an engaged condition in the folding zone. The two or more jaws move out of the folding zone when the two or more arms pivot to the release condition. This allows for the one or more mandrels to move in and out of the folding zone in an unobstructed manner.

The presealer arrangement described herein allows for accurate setting of the two or more jaws because the two or more jaws can be moved closer to the carton sleeve to allow the jaws to make contact with the carton sleeve at an angle that is parallel, or as close to parallel as possible, when the two or more arms are moved to the hold condition.

In order that the invention may be clearly and completely disclosed, reference will now be made, by way of example, to the accompanying drawings, wherein: Figure 1 is a perspective view from above of a presealer arrangement;

Figure 2 is an end elevation of the presealer arrangement with arms thereof in a release condition;

Figure 3 is a view corresponding to that of Figure 2, but with the arms in a hold condition;

Figure 4 is a view corresponding to that of Figure 3, but with jaws engaged and folding bottom closure panels of the carton sleeve at score lines;

Figure 5 is a side elevation of the presealer arrangement in its condition of Figure 4;

Figure 6 is a top plan view of the presealer arrangement;

Figure 7 is a vertical sectional view of the presealer arrangement taken on the line 7, 8 - 7, 8 shown in Figure 6 and with the jaws folding the panels; and

Figure 8 is a view similar to Figure 7 but with the jaws having folded the panels.

Referring now to all of the Figures generally, a presealer arrangement 10 is shown. The presealer arrangement 10 as shown is used for a four-way carton bottom end closure score line breaker assembly. The presealer arrangement 10 has a frame member 12 positioned above a folding zone 14.

The zone 14 is a volume where the presealer arrangement 10 folds and forms bottom end closures of carton sleeves by carrying out folding operations which will be described in further detail below. One or more mandrels 16 are movable, along a path 18, into and out of the folding zone 14. The path 18 can be a linear conveyor as shown, a rotatable table, or other suitable device for moving the carton sleeves in and out of the folding zone. A carton sleeve 20 is placed over each mandrel 16. The carton sleeves 20 are of a laminate comprised of paperboard with innermost and outermost moisture barrier thermoplastics layers, possibly with the interposition of an oxygen barrier layer. Predetermined surface areas of the bottom end closure panels are typically heated in order to render them tacky for sealing. The or each mandrel 16 having a carton blank 20 positioned thereon moves into the folding zone 14 to be operably engaged by the presealer arrangement 10 for the folding operation to occur. The frame 12 of the presealer arrangement 10 carries at each end of the folding zone 14 a first lever 22 and a second lever 24 that are pivotally connected to the frame 12 at pivot points 26. Each of the levers 22 and 24 has a free- ended arm 28 located below the pivot point 26 and a control arm 30 located above the pivot point 26. The arms 28 pivot between a hold condition and a release condition. When the arms 28 move to the hold condition, they move toward the folding zone 14. When the arms 28 move to the release condition, they move away from and out of the folding zone 14.

When the arms 28 move to the hold condition, rails 32 carried by the arms engage respective opposite sides of the carton sleeve 22 and press them against the mandrel 16. The rails 32 press on the carton sleeve 20 to hold the carton sleeve 20 in place during the folding operation described below.

A first jaw 34 is pivotally mounted at pivot points 37 on the two arms 28 of the levers 22. A second jaw 36 is pivotally mounted at pivot points 37 on the two arms 28 of the levers 24. Together, the two jaws 34 and 36 facilitate the folding of the bottom end closure panels of the carton sleeve 20. Each of the jaws 34 and 36 has a tacking and/or tucking element 38 which is used to form the ends of the carton sleeves 20 during the folding operations. The jaws 34 and 36 move between engaged and disengaged conditions. When the jaws 34 and 36 are in the engaged condition, the elements

38 contact and fold inwardly the substantially rectangular, bottom end closure panels of the carton sleeve 20 and then press the bottom end closure against the mandrel 16 in the folding zone 14. When the jaws 34 and 36 are in the disengaged condition, they are generally adjacent to their respective arms 28. When the jaws 34 and 36 are moved to the disengaged condition and the arms 28 move to their release condition, the jaws 34 and 36 are moved out of the folding zone 14. This allows the unobstructed movement of the mandrel 16 and the carton sleeve 20 into and out of the folding zone. At the same time as when the arms 28 move to the engaged condition, the jaws 34 and 36 are moved into the folding zone 14 in close proximity to the carton sleeve 20. This allows for more accurate folding of the carton sleeve 20 since the jaws 34 and 36 can be placed closer to the carton sleeve 20 during a folding operation while still allowing the jaws 34 and 36 and the arms 28 to swing clear of the folding zone 14 when the one or more mandrels 16 are moving in or out of the folding zone 14. By providing a way of moving the jaws closer to the sleeve, more accurate folding is achieved, while also avoiding damage to the mandrels, carton sleeves and components of the presealer arrangement 10 by keeping components clear of the mandrels 16 during movement of the mandrels in and out of the folding zone 14. Additionally, the contact between the jaws 34 and 36, on the one hand, and the respective substantially rectangular end closure panels, on the other hand, is nearly parallel with the external surfaces of those panels. This allows for a clean, even fold along the respective score lines of the carton sleeve at the respective opposite edges of the end face of the mandrel 16.

During the folding operation, the presealer arrangement

10 uses movable fingers 42 that pivot into the folding zone

14 and pinch inwards two sides of the bottom end closure, namely those having triangular panels. Thus, the movable fingers 42 causes the two sides of the end closure to fold inward while the jaws 34 and 36 pivot to the fold condition.

Each arm 28 can optionally have one or more ramps 40 connected thereto, to take account of the possibility that the setting-up of components, such as the levers 22 and 24 and/or the mandrel (s) 16, has been inaccurately performed. The ramps 40 can be Teflon® ramps that will gently contact the mandrels 16 in the event that the arms 28 are not clear from the path of movement of the mandrels 16. If engagement between the mandrels 16 and the ramps 40 occurs, the ramps 40 will cause the arms 28 to pivot out of the path and prevent damage to the presealer arrangement, the carton sleeve 20 and the mandrel 16. This is particularly desirable because of the expense and time involved in repairing or replacing a damaged mandrel.

The movement of the arms 28 between the hold condition and the release condition is controlled by a pair of arm actuator arrangements generally indicated at 43. Each arm actuator arrangement 43 includes an actuator or motor 44 connected to a linkage plate 46. The linkage plate 46 has a first linkage 48 and a second linkage 50 connected thereto and extending toward the respective control arms 30 of the levers 22 and 24. The first linkage 48 is connected to an arm post 52 on the arm 30 of the lever 22. The second linkage 50 is connected to an arm post 52 located on the control arm 30 of the lever 24. Movement of the linkage plate 46 up and down causes the first linkage 48 and the second linkage 50 to pivot about the linkage plate 46 and the arm posts 52 to pull and push the arms 28 between the hold and release conditions upon the actuation of the motor 44.

Actuation of the jaws 34 and 36 between the engage condition and the disengaged condition is controlled by a jaw actuator arrangement 54. The actuation of the jaws 34 and 36 is now described with reference to Figures 6 to 8. The actuator arrangement 54 is located in a generally central area of the presealer arrangement 10. Referring to Figure 7, the jaws 34 and 36 are shown engaged with the respective, substantially rectangular, bottom end closure panels in the process of folding them inwardly. Figure 8 shows the jaws 34 and 36 in the completed fold condition where the bottom end closure of the carton 20 has been completely folded. The jaws 34 and 36 move between the disengaged condition, shown in phantom in Figure 7, and the engaged condition, shown in solid lines in Figures 7 and 8. The jaw actuator arrangement 54 has a jaw actuator or motor 56 that moves a linkage plate 58 up and down with reference to the carton sleeve 20. Connected to the linkage plate 58 are linkages 59 and 59' that are each connected at one end to the linkage plate 58 and at a second end to a pivot point 60 or 60' on the corresponding jaw 34 or 36. It is possible to use a greater or lesser number of linkage assemblies depending upon the size of the jaw.

In Figure 7 the actuator 56 is being actuated to cause the linkage plate 58 to move upward, which translates through the linkages 59 and 59' and the pivot points 60 and 60' to cause the jaws 34 and 36 to pivot inward with respect to the folding zone 14 and cause the carton sleeve 20 to be folded. In Figure 8 the actuator 56 has caused the linkage plate 58 to move upward to the point where the jaws 34 and 36 are in the completed fold condition.

The presealer arrangement 10 shown in the Figures is set up to fold two carton sleeves (on respective mandrels 16) at one time. The jaws 34 and 36 span across two cartons, allowing the folding of two carton sleeves in the folding zone 14 at one time. It is possible to enlarge the folding zone 14 to fold more than two carton sleeves at one time, or the folding zone 14 can be smaller and the presealer arrangement can fold a single carton sleeve at a time. The number of carton sleeves processed depends on the particular needs of the application as well as other factors such as the amount of manufacturing space that is available.

Claims

1. Apparatus for folding semi-rigid sheet material in forming a container from said sheet material, comprising a mounting device arranged to be oscillatable relative to said sheet material, a jaw pivotally mounted on said mounting device and whereof the axis of turning is oscillatable with said mounting device relative to said sheet material and which is applicable in a substantially parallel manner to a part of said sheet material to be folded relative to another part of said sheet material.

2. Apparatus for folding semi-rigid sheet material in forming a container from said sheet material, comprising first and second mounting devices arranged to be oscillatable towards and away from one another relative to said sheet material, first and second jaws pivotally mounted on the respective mounting devices and whereof the axes of turning are oscillatable with said mounting devices relative to said sheet material and which are applicable in substantially parallel manners to respective parts of said sheet material to be folded relative to respective other parts of said sheet material.

3. Apparatus according to claim 2, and further comprising first and second fingers oscillatable towards and away from one another to fold inwards respective further parts of said sheet material which are among those respective parts of said sheet material to be folded relative to said other parts of said sheet material.

4. Apparatus according to claim 2 or 3, wherein the mounting devices are oscillatable as aforesaid also to hold said sheet material during the folding and to release said sheet material after the folding.

5. Apparatus according to any preceding claim, wherein the or each mounting device comprises a pivotable arm turnable relative to a support.

6. Apparatus according to any preceding claim and further comprising a mandrel for supporting said sheet material and for backing-up said other ρart(s) thereof.

7. Apparatus according to any preceding claim, wherein the or each mounting device carries a diverter arranged to steer the mounting device (s) and the jaw(s) out of a path of movement of said mandrel.

8. Apparatus according to claim 7, wherein the or each diverter is arranged to steer as aforesaid by being displaced by said mandrel.

9. Apparatus according to claim 7 or 8, wherein the or each diverter is a ramp.

10. Apparatus according to any preceding claim and in the form of a pre-sealing apparatus.

11. A method of forming a container of semi-rigid sheet material, including supporting said sheet material, applying a pivotably mounted jaw in a substantially parallel manner to a part of said sheet material, and turning said jaw, while said jaw remains substantially parallelly applied to said part, to fold said part relative to another part of said sheet material.

12. A method of forming a container of semi-rigid sheet material, including supporting said sheet material, applying first and second pivotally mounted jaws in respective substantially parallel manners to respective parts of said sheet material, and turning said jaws, while said jaws remain substantially parallelly applied to said respective parts, to fold said respective parts relative to respective other parts of said sheet material.

13. A method according to claim 12 and further including folding inwards respective further parts of said sheet material which are among those respective parts of said sheet material to be folded relative to said other parts of said sheet material.

14. A method according to any one of claims 11 to 13, and further comprising backing-up said other part(s) of said sheet material with a mandrel.

15. A method according to claim 14 and further including, prior to said turning, bringing said mandrel into a location opposite to the jaw(s) .

16. A method according to claim 15 and further including, between said bringing and said turning, displacing an axis of turning of the or each jaw inwardly to adjacent to said sheet material at end edge of said mandrel.

17. A method according to claim 15 or 16 and further including, during said bringing, displacing the jaw(s) outwardly under the action of said mandrel.

18. A method according to any one of claims 11 to 17 and further comprising, prior to said folding, pressing against said sheet material to hold said sheet material in position.

19. A method according to any one of claims 11 to 18, wherein said sheet material comprises a laminate comprised of an intermediate layer of cellulosic material and innermost and outermost layers of thermoplastics.

20. Apparatus for folding sheet material in forming a container from said sheet material, comprising first and second holding devices arranged to be oscillatable towards and away from each other relative to said sheet material to hold said sheet material in a desired position and to release said sheet material, and a drive device common to and mechanically connected to said first and second holding devices for operating the same.

21. Apparatus according to claim 20, wherein said holding devices comprise respective first and second oscillatable arms.

22. Apparatus according to claim 20 or 21, and further comprising first and second jaws pivotally mounted upon the respective first and second holding devices and serving to fold respective parts of said sheet material relative to respective other parts thereof.