METHOD FOR PRODUCING A PACKAGING HAVING A CIRCUMFERENTIAL EDGE FLANGE AND A BARRIER FILM

Abstract

A method for producing packaging comprises providing the shell part that defines an opening, a cavity at least partially formed by a bottom wall and side walls, and a continuously circumferential lower contact surface at a constant height around the opening of the cavity and providing a collar including the circumferential edge flange. At least one bottom tool is structured to comprise aa lower contact surface and a cavity configured to receive the shell part. At least one top tool is structured to comprise an upper contact surface. The shell part is inserted into the cavity of the at least one bottom tool and the collar is placed on the lower contact surface. A barrier film is placed over the edge flange and pressed to form a tray that is filled with goods. A sealing film is then pressed against the barrier film to seal the goods within the tray.

Claims

1. A method for producing packaging having a circumferential edge flange and a shell part, the method comprising: providing the shell part comprised of a cellulose-containing material, wherein the shell part defines an opening at an upper end, a cavity at least partially formed by a bottom wall and side walls, and a continuously circumferential lower contact surface at a constant height around the opening of the cavity; providing a collar including the circumferential edge flange comprised of one of cardboard, paperboard, corrugated board, and paper; structuring at least one bottom tool to comprise a cavity configured to receive and support the shell part; structuring at least one top tool to comprise a flat, continuously circumferential upper contact surface at a constant height and positioned corresponding to the lower contact surface of the shell part when the at least one top tool is positioned on top of the at least one bottom tool; inserting the shell part into the cavity of the at least one bottom tool; placing the collar comprising the edge flange on the lower contact surface of the at least one bottom tool; covering the edge flange with a barrier film; pressing the barrier film against a top side of the collar and of the shell part to form a tray; filling the tray with goods; positioning a sealing film above the tray so that it covers the edge flange; pressing the sealing film using the at least one top tool in a continuously circumferential manner against a top side of the barrier film on the edge flange to seal the sealing film against the barrier film while preserving the edge flange of a uniform thickness, and wherein the at least one bottom tool and the at least one top tool are configured to produce packaging from at least one of: (1) shell parts which differ in thicknesses; and (2) collars which differ thickness.

2. The method according to claim 1, wherein the tray comprises a shape that is one of: (a) round; and (2) polygonal.

3. The method according to claim 1, further comprising applying a vacuum to an underside of the shell part to press the barrier film against the top side of the collar and against the shell part.

4. The method according to claim 1, wherein the barrier film is pressed against the top side of the edge flange by the at least one top tool and is connected to the top side of the edge flange.

5. The method according to claim 1, wherein the at least one top tool further comprises a punch configured to press the barrier film against the top side of the shell part and the collar.

6. The method according to claim 5, wherein at least one of the shell part and the collar comprises an adhesive surface, and wherein the collar and the shell part are compressed by the punch of the top tool and are bonded to one another by activating the adhesive surface.

7. The method according to claim 1, wherein the at least one top tool further comprises a frame configured to press the barrier film against the top side of the edge flange.

8. The method according to claim 1, wherein the at least one bottom tool further comprises: an upper bottom tool part comprising the circumferential lower contact surface; multiple lower bottom tool parts defining multiple cavities for the shell part; and multiple trays comprising shell parts that are produced with the same upper bottom tool part and the lower bottom tool part which matches the shell part.

9. The method according to claim 1, wherein the barrier film is heated by at least one of: (1) heat conduction; (2) radiation; and (3) convection.

10. The method according to claim 9, wherein the sealing film is heated by at least one of: (1) heat conduction; (2) radiation; and (3) by convection.

11. The method according to claim 1, wherein at least one of: (1) the shell part is formed by pressing a cellulose-containing flat material; and (2) the collar is formed from a blank made of one of cardboard, paperboard, corrugated board, paper, and any other foldable flat material.

12. The method according to claim 1, wherein the barrier film comprises at least one ply made of one of PET, PLA, EVOH, PA, PBT, PP, and PE.

13. The method according to claim 1, wherein at least one of: (1) the barrier film is produced from at least one biopolymer; (2) the barrier film is produced from at least one renewable raw material; and (3) the barrier film is produced from at least one compostable raw material.

14. The method according to claim 1, wherein the shell part and the collar are connected to one another before the barrier film is pressed against the collar and shell part and is connected thereto to form the tray.

15. The method according to claim 1, wherein at least one of the shell part and the collar is printed with a coating configured to influence adhesion of the barrier film onto the top side of the collar and to the shell part to form the tray.

16. The method according to claim 1, wherein the same at least one bottom tool and the same at least one top tool are configured to connect the shell part, the collar, and barrier film to form the tray.

17. The method according to claim 1, further comprising another bottom tool and another top tool configured to connect the filled tray to the sealing film.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The invention is explained in greater detail below with reference to the appended drawings of an exemplary embodiment, wherein:

[0031] FIG. 1 illustrates a top perspective view of an embodiment of a shell part and a collar;

[0032] FIG. 2 illustrates a perspective top view of an embodiment of a bottom tool having multiple cavities for the simultaneous production of trays;

[0033] FIG. 3 illustrates a perspective top view of the embodiment of the bottom tool of FIG. 3 with inserted shell parts and collars as well as a barrier film arranged thereabove; and

[0034] FIG. 4 illustrates a sectional view of the sealing of the filled trays with a sealing foil by means of a bottom tool and a top tool.

DETAILED DESCRIPTION OF THE INVENTION

[0035] According to FIG. 1, a shell part 1 has a bottom wall 2 and side walls 3 which are each inclined slightly outwards. At the edges, neighboring side walls 3 abut one another. The side walls 3 are trapezoidal, with their width increasing from bottom to top in order to bring about the outward inclination. In the example, the shell part 1 is octagonal.

[0036] A collar 4 has a flat, continuously circumferential edge flange 5 of uniform thickness, which likewise has eight sides. Each straight-lined portion of the edge flange has a trapezoidal tab 6 at the inner edge, the width of which decreases from top to bottom.

[0037] In FIG. 1, the shell part 1 and the collar 4 are shown in the erect state, in which they are glued together. For this purpose, the collar 4 is placed from above onto the shell part 1 and bonded at the tabs 6 to the adhesive surfaces 7 on the insides of the side walls 3 of the shell part 1.

[0038] According to FIG. 2, a bottom tool 8 of a laminating station 9 has three applications 10 for simultaneously producing three trays. Each application comprises a cavity 11, the outer shape of which corresponds to the shape of a shell part 1. Furthermore, each application 10 comprises a circumferential contact surface 13 around an upper opening 12 of the cavity 11 for supporting an edge flange 5 of a collar 4.

[0039] In a lower delimiting surface 14 of each cavity 11, which corresponds to the bottom wall 2 of a shell part 1, one or more suction openings 15 open out from vacuum channels 11, to which a vacuum pump can be joined.

[0040] According to FIG. 3, a pre-glued shell 16 made of a shell part 1 with a collar 4 is inserted in each application 10. Furthermore, a barrier film 17 is stretched across all of the applications 10. In this state, the barrier film 17 is heated and pressed against the top sides of the shell part 1 and of the collar 4 by applying a negative pressure to the suction openings 15 and is connected thereto to form a tray 18. The barrier film 17 can be heated by means of a heating apparatus which is not shown. The heating apparatus can be, for example, a hotplate, a radiator or a fan heater. The barrier film 17 can be additionally squeezed against the top side of the edge flange 5 by means of the top tool. For this purpose, the top tool can have a frame which is adapted to the contact surface 13 or the edge flange 5.

[0041] According to FIG. 4, trays 18 prepared in such a way are already filled with goods 19, e.g., with a food or convenience food. The filling can be carried out in a filling station which is arranged upstream of the sealing station 20 shown in FIG. 4.

[0042] The sealing station 20 comprises a bottom tool 21 and a top tool 22. The bottom tool 21 likewise has three cavities 23, in which the shell parts 1 of the trays 18 sit, and circumferential lower contact surfaces 25 around the openings 24 of the cavities 23, on which lower contact surfaces the underside of the circumferential edge flanges 5 sit. The top tool 22 has, on the underside, upper contact surfaces 26 on strip-shaped heating apparatuses 27, which extend circumferentially over each edge flange 5. The heating apparatuses 27 cover both adjacent edge flanges 5 on the abutting edge flanges 5 of neighboring trays 18. A sealing film 28 is arranged between the bottom tool 21 and the top tool 22.

[0043] The sealing film 28 can be pressed against the edge flanges 5 by means of the top tool 22 and can be heated at the same time such that it is connected to the sealing film 28 on the edge flanges 5. The top tool 22 can be configured in such a way that, after the connection of the sealing foil 28 to the edge flanges 5 has been produced, it detaches the sealing film 28 circumferentially around the edge flanges 5.

[0044] Trays 18, which differ from one another in terms of the thickness of the shell part 1, the thickness of the collar 4 and/or the thickness of the shell part 1 and of the collar 4, can be processed by means of the same tools 8, 21, 22. This is due to the fact that the barrier film 17 is pressed onto the insides of the shell part 1 and collar 4 by applying a vacuum, and is connected thereto. Furthermore, this is due to the fact that the collars 4 circulate continuously with a uniform thickness and in a plane, as do the lower contact surfaces 25 and the upper contact surfaces 26 of the bottom and top tools 21, 22. As a consequence, the tools do not require any compensation during the processing of trays 18 having different thicknesses.

LIST OF REFERENCE NUMERALS

[0045] 1 Shell part [0046] 2 Bottom wall [0047] 3 Side walls [0048] 4 Collar [0049] 5 End flange [0050] 6 Tab [0051] 7 Adhesive surface [0052] 8 Bottom tool [0053] 9 Laminating station [0054] 10 Application [0055] 11 Cavity [0056] 12 Opening [0057] 13 Contact surface [0058] 14 Lower delimiting surface [0059] 15 Suction openings [0060] 16 Shell [0061] 17 Barrier film [0062] 18 Tray [0063] 19 Goods [0064] 20 Sealing station [0065] 21 Bottom tool [0066] 22 Top tool [0067] 23 Cavity [0068] 24 Opening [0069] 25 Lower contact surface [0070] 26 Upper contact surface [0071] 27 Heating apparatus [0072] 28 Sealing film