EP2459332A1

EP2459332A1 - Device for forming deep-drawn containers

Info

Publication number: EP2459332A1
Application number: EP10732655A
Authority: EP
Inventors: Dick Cornelis Verbeek; Harry Johan Kettelarij
Original assignee: Amcor Flexibles Kreuzlingen AG
Current assignee: Amcor Flexibles Kreuzlingen AG
Priority date: 2009-07-30
Filing date: 2010-07-06
Publication date: 2012-06-06
Anticipated expiration: 2030-07-06
Also published as: EP2459332B1; ES2421487T3; AU2010278373A1; PL2459332T3; RU2012121171A; US20120119418A1; WO2011012196A1; HRP20130783T1; DE102009035680A1; US9302315B2; RU2510827C2; CA2768380A1; JP2013500163A; DK2459332T3

Abstract

The invention relates to a device (40) for forming deep-drawn containers (1), having a mold (41) of conical shape interacting with a stamping body (10; 20; 30), which operatively connects with a material web (2) when the stamping body (10; 20; 30) is immersed in the mold (41), wherein at least at its outer periphery, wherein the stamping body (10; 20; 30) is made of an elastic material, and wherein on the side facing the material web (2), the stamping body (10; 20; 30) has a shape, the conicity of which is less than the conicity of the mold (41). According to the invention, it is provided that the stamping body (10; 20; 30) is slightly smaller than the opening region (45) of the mold, and that, when completely immersed in the mold (41), the stamping body (10; 20; 30) has a clearance (44) to the material web (2), at least in the later peripheral area (5) of the container (1).

Description

Device for forming thermoformed containers

The invention relates to a device for forming thermoformed containers according to the preamble of claim 1.

Such a device is known from US 4,562,717. In the known device to avoid irregularities in the cup wall, in particular of folds, an existing of an elastic material punch body is used. The punch body, which cooperates with a conically shaped die, which determines the outer shape of the cup, in this case has a slope between 0 degrees and 20 degrees. Furthermore, the punch body has a centric

arranged recess, the shape of which is frustoconical, wherein in the recess additionally a cylindrically shaped receiving pin is arranged. During deep drawing of the container is in the final position of the punch body, in which the punch body is completely immersed in the die, the clearance between the cylindrically shaped pin and the punch body by a deformation of the punch body

completed. Furthermore, the stamp body is located at his

Outer circumference completely on the material web in the area of the die.

It has been found that with such a device, although the mentioned irregularities or wrinkles in the wall of the container can be avoided, however, that the stackability of the container is relatively poor. This is under a good

Stackability of the container understood the property that nestled containers as completely as possible rest against the peripheral edge of the container, so that at a certain stack height as many containers stack each other and the stack has the same vertical orientation as possible. If this is not the case, both in processing the container in one

Packaging machine that fills and closes the containers, as well as in the handling of the container, especially when removing individual containers from a stack of containers in a storage magazine requires a lot of effort. Based on the illustrated prior art, the invention has the object, a device for forming deep-drawn containers according to the preamble of claim 1 such that their stackability is improved. This object is achieved in a device for forming deep-drawn containers with the features of claim 1.

The invention is based on the idea that in the end position of the plunger body, in which this is in its lowest position in the die, between the plunger body and the container wall in the region of the opening portion of the container, a free space is formed. It has been found that thereby when moving out of the punch body from the die or during removal from the container, this in the region of the opening of the container, which covers the area of

Becherrandes forms, have a very high, consistent accuracy or taper. As a result, the stackability of the container is significantly increased or improved.

Advantageous developments of the device according to the invention for molding deep-drawn containers are specified in the subclaims. All combinations of at least two features disclosed in the description, the claims and / or the figures fall within the scope of the invention. Here, it is provided in a preferred embodiment of the invention for easy formation of the free space that the punch body has a region which is reduced in its cross-sectional area with respect to the initially reaching the material web in operative connection region of the punch body and that the first with the

Material web in operative connection area has a height of at least 5 mm.

It is also preferred that the die has a taper angle of 1 degree to 20 degrees, in particular of 5 degrees to 12 degrees, and that the punch body in the container wall forming portion is cylindrical or has a taper which is smaller than the taper the container wall, wherein Konizitätswinkel the area especially between 0 degrees and 8 degrees. Through this

Training containers are formed, which can be easily demolded.

A particularly simple producibility of the stamp body is achieved when the stamp body has at least two regions, one of which is a region of the container wall forming region and the other region of the region by the stamper body has the free space to the container wall. Natural rubber, acrylonitrile-butadiene rubber or urethane rubber have been found to be preferred materials for the production of the stamper bodies.

Furthermore, tests have shown that in the materials mentioned it is advantageous if the punch body has a hardness of 50 ShA to 130 ShA, preferably from 70 ShA to 95 ShA.

The molding process can be facilitated if the material of the

Stamp body contains at least one additive, in particular a fluorine-based lubricant improving additive, such as Teflon®.

In addition, it may be provided that the material of

Stamp body contains a filler or a substance for reinforcement such as carbon black, silicon, clay or chalk.

For fixing and guiding the stamp body in the device, it may be provided that the stamp body is vulcanized onto a carrier element consisting of metal. To achieve a high accuracy and dimensional stability of the container, it is proposed in a further advantageous embodiment that the punch body is annular and cooperates with an insert consisting of metal, which is connected to a carrier element consisting of metal. Through the use of a good centering of the web and a longer life of the punch body can be achieved. In particular, it may be advantageously provided that a particular annular space is formed between the insert and the punch body. In order to be able to form an embossed cup bottom, it is provided that the insert is formed on the side opposite the carrier element as an embossing plate with a structure (embossing edge), which forms the

Bottom area of the container shapes. Further advantages, features and details of the invention will become apparent from the following description of preferred Ausfϋhrungsbeispiele and with reference to the drawings.

These show in:

1 shows a first punch body for molding round containers with a carrier element without using an insert in a side view, FIG. 2 shows a second punch body for forming round containers using an insert and a carrier element in longitudinal section, FIG.

3 shows the insert used in FIG. 2 in a longitudinal section,

4 shows a third punch body for forming containers which have an approximately octagonal shape without use of an insert in plan view, FIG. 5 shows the punch body according to FIG. 4 in a side view with its carrier element, FIG.

Fig. 6

to

Fig. 8 shows the manufacturing process of a container using the plunger body shown in FIG. 1 during different phases in each case in simplified longitudinal sections and Fig. 9: a plurality of stacked containers, which under

Use of a device according to FIGS. 6 to 8 were produced in longitudinal section.

FIG. 1 shows a first stamp body 10 for molding round containers 1 (see also FIG. 9). The rotationally symmetrical formed stamp body 10 may for example consist of natural rubber, an acrylonitrile-butadiene rubber or a urethane rubber, or at least contain these materials. alternative

Die body materials are synthetic polyisoprene rubber, styrene-butadiene rubber, hydrogenated nitrile rubber, acrylic rubber, epichlorohydrin rubber, epichlorohydrin-ethylene oxide rubber, chloroprene rubber,

Polybutadiene rubber, butyl rubber or ethylene-propylene-diene monomers.

The hardness of the stamp body 10 is in this case between 50 ShA and 130 ShA, preferably between 70 ShA and 95 ShA. The materials of the stamp body 10 may contain activators and / or accelerators for a later-mentioned vulcanization process, plasticizers or plasticizers, stabilizers, in particular against oxidation and ozone attack, processing aids, tackifiers and / or reinforcing agents or fillers. When

Reinforcing agents or fillers, the punch body 10th

For example, carbon black, silica, alumina, chalk or lime. The stamp body 10 can at least on the shaping surface or through the entire stamp body material through with lubricants, such as fluoride-containing polymers or

Polyhalogenolefine, such as polytetrafluoroethylene (TEFLON®), α-boron nitride or graphite, be provided. Furthermore, dyes are possible, the

Stamp body 10 appear as desired or need in a desired color. The punch body 10 has a through bore 11 in its longitudinal axis. Here, the diameter d of the bore 11 is about half of the diameter D of the punch body 10 ± 15 mm. Of the Diameter D of the punch body 10 corresponds to the inner diameter of the container 1 ± 3 mm.

The stamp body 10 has two regions 13 and 14. Here, the first region 13 has a larger diameter than the second region 14. The lateral surfaces 15, 16 of the regions 13, 14 are either cylindrical, or have a small conicity, wherein the angle location of the lateral surface 15 and the angle α2 of the lateral surface 16 can each be between 0 degrees and 8 degrees. The height h of the region 14 is between 0 mm and the total height H less 5 mm, wherein the diameter in the region of the lateral surface 16 can be up to 20 mm less than the diameter D.

The stamp body 10 described so far can on a

Carrier element or a support plate 18 be vulcanized. This can be achieved by a solvent based two-component or

One-component system or by means of a water-soluble

Binding system done. Vulcanized stamper bodies 10 may be vulcanized by sulfur or peroxide treatment. The support plate 18 may be made of e.g. nitrided or case hardened or case hardened nitrided steel. In this case, the support plate 18 made of metal approximately has an outer diameter which corresponds to the outer diameter of the stamp body 10. 2, a second punch body 20 is shown. The second

Plunger body 20 differs from the first plunger body 10 substantially by the use of a in the bore 21st

The insert body 22 has a cylindrical portion 23 which widens in diameter on the side opposite the support plate 24 side. The upper side 25 of the insert body 22 may in this case be formed as an embossing plate, which by way of example has an elevated, radially surrounding embossing edge 27, which forms a corresponding recess in the bottom region of a container 1 (FIG. 3).

In the longitudinal axis of the insert body 22, a receiving bore 28 is still formed, in which a screw, not shown, can be arranged, which screwed the insert body 22 with the support plate 24 or braced, and which may have a ventilation hole. The attachment of the punch body 20 with the support plate 24 via the screwed to the support plate 24 insert body 22, so that can be dispensed with a vulcanization of the punch body 20. The outer diameter or the shape of the insert body 22 is such that between the outer periphery of the insert body 22 and the

Inner circumference of the second punch body 20, an annular space 29 is formed. In Figs. 4 and 5, a third punch body 30 is shown for forming approximately octagonal containers. Here, the length L of the inner length of the container corresponds to ± 3 mm. The length I corresponds to the length L less twice the wall thickness t ± 5 mm. The width B corresponds to the inner width of the container ± 3 mm. Furthermore, the inner width b of the width B is less than twice the wall thickness t ± 5 mm. The outer one

Radius R is between 2 mm and 40 mm, while the inner radius r is approximately between 0.5 mm and 30 mm. The height H corresponds to the height of the containers. Here, too, the region of the plunger body 30 facing away from the carrier plate 31 can be enlarged relative to the region facing the carrier plate 31 corresponding to the two punch bodies 10, 20 (not shown). Also, according to the punch body 20, the punch body 30 may be formed using an insert. Further, the outer shape of the punch body 30 may be either cylindrical, or have a taper angle α3 of 0 degrees to about 8 degrees.

In FIGS. 6 to 8, the production process of a container 1 from a material web blank cut from a material web 2 immediately before is described by means of a device 40.

The material webs 2 may contain, for example, an aluminum substrate. In particular, the aluminum substrate is at least one aluminum foil which is coated by lamination and / or extrusion, such as by coextrusion with, for example, plastics or paints. Typical webs may have one of the following two layer constructions, including the layers:

Sealing layer / aluminum foil / paint or

Sealing layer / aluminum foil / core layer / aluminum foil / lacquer

Typical sealing layers are, for example, polypropylene sealing layers in a thickness of 20 μm to 200 μm or off

Sealing layers of polyethylene in a thickness of 20 microns to 200 microns. The sealing layers can form a release-resistant compound with the seal or can form a peelable layer and the

Sealing layers can absorb pressure and impact forces from case to case. The core layer can be, for example, a polypropylene or polyethylene, for example in the form of a film having a thickness of 20 μm to 200 μm. The aluminum foil may have a thickness of 20 .mu.m to 200 .mu.m, particularly preferably between 80 .mu.m and 160 .mu.m and in particular be a soft alloy, semi-hard alloy or three-quarter hard alloy. The applied lacquers can be, for example, per se known lacquers, such as acrylic lacquers, PVC lacquers, cellulose lacquers, stoving lacquers, epoxy-containing lacquers, nitro lacquers, etc.

Further applicable material webs may, for example, have one of the following layer constructions: PP / aluminum / foam / aluminum

PP / aluminum / PP foam PP / aluminum PP / aluminum / PP foam - PP

PP / aluminum / PP foam PP / aluminum / foam The layer designated PP is in particular one against the

Inside of a container directed polypropylene sealing layer. An alternative possibility is a sealing layer, directed against the inside of a container, made of polyethylene. In a further embodiment it is possible to provide an inner PP or PE layer and a polyethylene or polypropylene adhesive layer adjacent thereto. The adhesive layer of polypropylene, resp. Polyethylene, may have a thickness of 10 microns to 60 microns. The sealing layers may for example have a total thickness of 20 microns to 200 microns.

The foam material may be a closed-cell plastic foam, for example made of a polyolefin, such as polypropylene (PP foam), or a polyethylene terephthalate foam (PET), used as C-PET or A-PET. The material pairing PP-foam-PP indicates a multi-layer composite of two outer layers or cover films,

for example, a thickness of 12 to 200 microns, polypropylene and an interposed foam layer of e.g. Polypropylene or polyethylene terephthalate out. The foam layers can have a thickness of 500 μm to 2000 μm.

The aluminum has a thickness of advantageously 20 μm to 200 μm, preferably 80 μm to 160 μm, and is e.g. a soft, semi-hard or three-quarter hard alloy.

Other applicable webs include: PP / aluminum / PP or oPA (oriented polyamide) or

PP / substrate / paint

PP refers to a polypropylene sealing layer, PE to a polyethylene sealing layer, whereby the sealing layer can be designed to be fully adhesive or peelable. There are layer thicknesses for the PP

(Polypropylene) from 20 microns to 80 microns advantageous. The oriented polyamide may in particular be bi- or monoaxially oriented and have a thickness of 10 μm to 50 μm. The aluminum has a thickness of advantageously 20 .mu.m to 100 .mu.m and is, for example, a soft, semi-hard or three-quarter hard alloy. It can in turn be used the commercial paints. Another material web 2 which can be used can be produced by extrusion coating of chromium-plated steel (ECCS) of the exemplary construction: sealing lacquer / steel / decorative lacquer. The sealing wax may contain polypropylene, PVC, PET or epoxy or combinations thereof and may be used in amounts of from 2 g / m ² to 12 g / m ² . The steel may have a thickness of 130 microns to 170 microns and is advantageously soft and deeply tempered. The paints, including decorative paints, are commercially available paints, for example in different shades.

From the material webs 2 can by means of the inventive device 40 containers, for example in plan view

rotationally symmetrical containers, with outside diameters D of 12 to 150 mm and inside diameters D ₁ of 55 to 145 mm are produced. The side wall angle can be between 1 and 20 °. The height of a container (H), related to the deep draw ratio (ß), can be represented as follows:

H _max . ~ 0.5 x D ₁

It is also possible to produce containers with non-rotationally symmetrical top view by means of the device according to the invention. For example, in plan view, oval or polygonal, such as rectangular or square, but also 5-, 6-, 8-square, etc. containers can be made. Typical radii for corner areas are between 2 and 40 mm at the outer edge and 0.5 to 30 mm at the inner edge (inner radius r) of the side wall. The length of the side edges is not critical. The height of a non-rotationally symmetrical container, based on the

Thermoforming ratio (ß), is approximately:

H max ~ 2.5 x inner radius r

In all the above-mentioned containers, a rolling edge 5 can be provided with a diameter of about 1 to 2.5 mm. The containers may have a sealing flange. The sealing flange, the hereinafter also referred to as a rolled edge 5 is suitably an endless sealing flange, and may for example be 2.5 to 5.0 mm wide. The side wall angle can be between 1 and 20 °. The method with the present device leaves a

Production speed of for example 50 to 150 and

in particular from 70 to 130 cycles / min. It has proved to be advantageous if the material web 2 is provided during processing in the device 40 with a layer of suitable lubricant, or oil or grease. In this case, layer quantities of 300 to 800 mg / m ² , in particular from 400 to 600 mg / m ^{2 have} proved to be advantageous.

The device 40 has an outer shape of the container 1

determining die 41 which cooperates by way of example with the punch body 10. Here, the inner wall 42 of the die 41 has a Konizitätswinkel α4 of 1 degree to 20 degrees, in particular from 5 degrees to 12 degrees, which demolding from the die 41 and a

Nesting of containers 1 allows or improves. Furthermore, the stamp body 10 has a slightly smaller size on the side facing the die 41 than the die 41 in the region of its

Opening cross-section 45.

As an example, for deep drawing of the container 1, the die 41 of

Device 40 in the direction of arrow 43 down against the rigidly arranged, and with the die 41 in its longitudinal axis

aligned punch body 10 moves, wherein the material web 2 is clamped by means not shown clamping means in a known manner. Here, when the plunger body 10 is dipped into the die 41, the plunger body 10 is compressed both axially and radially, whereby the material web 2 is drawn between the area 13 of the plunger body 10 and the inner wall 42, without leaving any clearance between the area 13 of the plunger body 10 and the inner wall 42 and between the inner wall 42 and the die 41 are. As a result, the side wall 4 of the container 1 is formed.

As can be seen in particular with reference to FIG. 8, in which the

Plunger body 10 has its end position with respect to the die 41 is between the side wall 4 and the region 14 of the punch body 10th a distance or clearance 44 is formed. This clearance 44 in this case consists in particular in the area of the later cup rim 5.

At the end of the deep-drawing process, the material web blank of the container 1 is formed in the region of its container rim, so that the rolled edge 5 is formed (FIG. 9).

As can best be seen from FIG. 9, it is essential that the side walls 4 of the containers 1 can be produced with a very high geometric accuracy or reproducibility by the special design of the stamp body 10. This makes it possible to achieve a good stackability of the containers 1, that is, in the case of several containers 1 stacked one inside the other, they are symmetrical to one another

Longitudinal axis 46 are arranged, wherein the rolling edges 5 of the container 1 seen over its entire circumference rest.

Claims

A device (40) for forming thermoformed containers (1), having a female mold (41) with a conical shape, which cooperates with a plunger body (10; 20; 30) which engages when the plunger body (10; 20; 30 ) into the die (41) with a material web (2) comes into operative connection, wherein the

Stem body (10; 20; 30) at least at its outer periphery of an elastic material and wherein the

Plunger body (10; 20; 30) on the material web (2)

facing side has a shape whose taper is less than the taper of the die (41), characterized in that the punch body (10; 20; 30) has a slightly smaller size than the opening portion (45) of the die (41) and, in the case of punch bodies (10, 20, 30) which are located completely in the die (41), the latter is at least in the later edge area (5) of the

Container (1) has a free space (44) to the material web (2).

2. Device according to claim 1, characterized in that the punch body (10; 20; 30) has a region (14) which in its cross-sectional area with respect to the first with the

Material web (2) in operative connection area (13) of the punch body (10; 20; 30) is reduced and that the first with the material web (2) in operative connection reaching area (13) has a height of at least 5 mm.

3. Apparatus according to claim 1 or 2, characterized in that the die (41) has a Konizitätswinkel (α4) of 1 degree to 20

And that the punch body (10; 20; Container wall (4), wherein Konizitätswinkel (α1) of the region (13) is in particular between 0 degrees and 8 degrees.

4. Apparatus according to claim 3, characterized in that the plunger body (10; 20; 30) has at least two areas (13, 14), of which one area (13) is the area forming the container wall (4) and the other area (14) the area in which the punch body (10; 20; 30) the clearance (44) for

Container wall (4).

5. The device according to claim 4, characterized in that the other region (14) has a Konizitätswinkel (α2) between 0 degrees and 8 degrees.

6. Device according to one of claims 1 to 5, characterized

in that the punch body (10; 20; 30) is made of

Natural rubber, an acrylonitrile-butadiene rubber or a urethane rubber.

7. The device according to claim 6, characterized in that the punch body (10; 20; 30) has a hardness of 50 ShA to 130 ShA, preferably from 70 ShA to 95 ShA.

8. Apparatus according to claim 6 or 7, characterized in that the material of the punch body (10; 20; 30) contains at least one additive, in particular a fluorine-based lubricant improving additive such as Teflon®.

9. Apparatus according to claim 8, characterized in that the material of the plunger body (10; 20; 30) additionally contains a filler or a substance for reinforcement, such as carbon black, silicon, clay or chalk.

10. Device according to one of claims 1 to 9, characterized

in that the stamp body (10; 20; 30) is vulcanised onto a support element (18; 24; 31) made of metal.

11. Device according to one of claims 1 to 9, characterized

in that the punch body (20; 30) is annular and has an insert (22) made of metal. interacts with a metal one

Carrier element (24, 31) is connected.

12. The device according to claim 11, characterized in that

between the insert (22) and the punch body (20; 30) a particular annular free space (29) is formed.

13. The apparatus of claim 11 or 12, characterized in that the insert (22) on the support element (24; 31) opposite side as a stamping plate having a structure

(Embossing edge 27) formed, which forms the bottom portion of the container (1).

14. Use of a device (40) according to any one of claims 1 to 13, characterized in that the device (40) for

Forms of a at least substantially a round outer shape having container (1) is used.

15. Use according to claim 14, characterized in that the outer diameter of the container (1) is between 12mm and 150mm.

16. Use of a device (40) according to any one of claims 1 to 13, characterized in that the device (40) for forming an at least one substantially polygonal

Outer shape container having rounded corners is used.

17. Use according to claim 16, characterized in that the corners of the container have an outer radius of 2mm to 40mm.

18. Use according to one of claims 14 to 17, characterized

in that the material web (2) consists at least partially of aluminum or steel, or in that the material web (2) comprises a laminated material web (2) using aluminum or

Steel is, for example, where plastic layers (for example PP or PE) are used as laminate layers, and wherein the Thickness of the aluminum or steel layer between 20 .mu.m and 200 .mu.m, in particular between 80 .mu.m and 160 .mu.m.