EP3010838B2 - Capsule having a capsule body and method for producing said capsule body - Google Patents

Description

The invention relates to a capsule according to the preamble of claim 1. Such capsules are used today in different forms for the preparation of a beverage, in particular coffee or tea in a beverage preparation machine.

The capsules fulfill a double function, on the one hand, by protecting the substance they contain from external influences and preserving their aroma, and on the other hand, by interacting with the beverage preparation machine, they also perform a mechanical function for the passage of hot water under high pressure. The capsule is received in a brewing chamber, which is closed pressure-tight for the brewing process. In many beverage preparation machines, when the brewing chamber is closed, the soil penetrates, so that hot water can penetrate into the interior of the capsule after the pump has been operated. The lid, which closes the capsule body, is either also perforated or it tears open in several places due to the build-up of internal pressure, so that the hot beverage can flow out of the brewing chamber. Such a capsule is for example in the WO 2012/080501 described.

The WO 2013/076519 A1 describes a capsule made of plastic material for the preparation of a drink with a side wall, a bottom and a lid. In the circumferential area of the base there are recessed zones which connect the base and the side wall to one another.

The WO 2012/144885 A1 also describes a closed capsule made of a plastic material with a circumferential collar for fastening the lid, on which a sealing element for sealing the capsule is arranged in a beverage preparation machine.

The WO 2012/127233 A2 describes a capsule made of plastic material with a side wall, a bottom and a lid, an inlet opening for liquid being arranged in the bottom of the capsule. This opening is closed by an inlet filter that is glued to the inside of the capsule on the bottom.

The US 2011/0033580 A1 also shows a capsule with a circumferential wall, a bottom and a lid to form a closed chamber. The bottom has at least one inlet opening, which is covered on the inside with an inlet filter.

The DE 10 2004 056 224 A1 describes a capsule made of plastic, the capsule bottom is provided with a central opening. This is covered with a piece of foil sealed on the inside, which consists of an aluminum foil.

A problem with capsules made of plastic material is that when the base is perforated due to the elasticity of the material, the base clings closely to the perforation means, so that the amount of water penetrating per unit of time is less than, for example, with aluminum capsules. It has therefore been shown that it is particularly advantageous to make additional openings in the base during the manufacture of the capsule, which increase the flow rate in the beverage preparation machine. These openings are advantageously slots which are produced without material removal and which are closed in the unpressurized state and assume a type of valve function under the action of pressure.

A disadvantage of this configuration, however, is that each individual capsule still has to be packed separately in an aroma-tight bag. However, it would be desirable to dispense with this additional packaging because an oxygen- and aroma-tight design of the capsule can be implemented without any problems apart from the openings in the base. It is therefore an object of the invention to provide a capsule of the type mentioned at the outset which does not require an additional outer casing and in which the flow rate in the beverage preparation machine can be controlled through any openings in the base of the capsule. According to the invention, this object is achieved with a capsule which has the features in claim 1.

The capsule body itself is already provided with a barrier layer in a manner known per se. Multi-layer plastic films with such a barrier layer are already known. Lids with barrier properties are also known. To prevent moisture or atmospheric oxygen from penetrating through the openings in the capsule base made by the manufacturer or aroma substance escaping, a membrane with barrier properties for sealing the closed chamber from the opening is arranged on the inside of the base. The membrane is connected to the floor along a connecting zone following the circumference of the floor. In this way, all the openings already made in the base are hermetically sealed, so that the base and the membrane are only pierced by the penetration means in the beverage preparation machine.

The dimensioning of the connection zone is chosen so that a sufficiently firm connection to the floor is guaranteed. It can be particularly expedient if the connection zone includes a central area of the capsule base, at which the membrane is not connected to the base. This unconnected area can serve to unevenness such as To compensate for folds or impressions in the membrane.

On the other hand, however, it can also be particularly expedient if the openings are at least partially arranged in the central region of the capsule base, on which the membrane is not connected to the base. In this way, the liquid penetrating through the openings in the non-connected Spread the membrane area immediately in all directions so that sufficient flow is maintained.

The capsule can be rotationally symmetrical, the connection zone being able to run in the form of a ring. Of course, the same principle can also be implemented, for example, in the case of a capsule with a poligonal cross-section with a poligonal capsule base.

In the case of an annular connection zone, it has proven to be particularly advantageous if the connection zone has an outside diameter between 14 and 17 mm and an inside diameter between 8 and 11 mm. With these materials, on the one hand, a secure connection between the membrane and the capsule base is guaranteed and, on the other hand, a sufficiently large central area remains on which the membrane is not connected to the base.

The term "barrier properties" is generally known to those skilled in the field of food packaging. Essential criteria are the oxygen permeability and the water vapor permeability in each case at a specific temperature of, for example, 23 ° C. or 25 ° C. For example, polyethylene vinyl alcohol (EVOH) is known as a plastic material with excellent barrier properties. This material is used as a barrier layer in laminated films and has permeability values in the range of 0.01 to 1. The oxygen permeability of plastic films is measured according to DIN 53 380. The value for the oxygen permeability results from cm ³ / m ² xdx bar. Permeability rates apply to the present application, as are already used in deep-drawn plastic capsules for portion coffee.

In certain cases it may also be expedient if the entire surface of the membrane is connected to the base of the capsule. Depending on the design of the penetration means on the machine, the openings can also bring about a better flow rate in such a case. This is particularly the case when the penetration means penetrate the bottom of the capsule in the area of the slots.

As already mentioned at the beginning, the opening is a slot which is closed in the unpressurized state and which can be expanded under the action of hydraulic, pneumatic or mechanical pressure. The individual slot can be straight or curved, or it can also be crossed slots. Advantageous embodiments of slit valves that open under the action of pressure are already known to the person skilled in the art from various fields of technology.

Of course, other types of openings can also be used instead of slots, in particular round or poligonal holes.

A particularly optimal effect is achieved if several openings, preferably at least three openings, are made in the floor. This is due to the fact that the relative position of the capsule to the penetration means is not always predictable in the beverage preparation machine. With at least three openings, however, the risk of an unfavorable relative position is considerably reduced.

The bottom particularly advantageously borders on the outer circumference of a stiffening zone which is formed by a plurality of indentations. The base for the passage of the liquid through the chamber in a beverage preparation machine can thus be penetrated with a penetration agent without the capsule body bending. A sufficient resistance on the capsule base is of particular importance in capsule bodies made of plastic material, since this material offers greater resistance to penetration than, for example, aluminum.

The indentations mentioned can have inner wall sections which lie on a common circumference, the diameter of the circumference corresponding approximately to the diameter of the membrane. In this way, the membrane is also centered by the inner wall sections, which has a positive effect on the manufacturing process.

The membrane consists of an aluminum-based film. This can also be a foil made of an aluminum alloy or a laminate with at least one aluminum layer. The lid for closing the capsule body can also be made from the same film material. Aluminum is known to have excellent properties with regard to the barrier effect against diffusion. For this reason, such films are often used for aroma-tight packaging in the food sector.

The capsule body is designed as a deep-drawn part. In the deep-drawing process, multilayer plastic films can be processed, which are precisely aligned to the packaging and the use of the capsule.

The invention also relates to a method for producing a capsule body for a capsule, which has the features in claim 11. It has proven to be particularly advantageous if the openings in the base of the capsule are made in a separate operation after the capsule body has been produced. In this way, the openings can be positioned exactly, which is particularly important for the desired effect. The membrane is then used, the surface configuration of which corresponds approximately to that of the base of the capsule. As already mentioned, the connection takes place along a connection zone following the circumference of the base.

An optimization of the manufacturing process is further achieved in that the capsule body is manufactured in a deep-drawing process, the bottom preferably being designed as a flat surface. The openings are easier on a flat surface attach as if it was arched. Finally, the membrane can also be applied better on a flat floor surface.

The opening is formed without material removal by means of an incision in such a way that a slot which closes itself in the idle state is created. The bottom is preferably pierced with a sharp blade. Of course, the openings could also be punched out or burned out using laser beams, for example.

The membrane is advantageously connected to the floor by heat sealing, the membrane having a correspondingly sealable layer, e.g. can be equipped with a sealing wax. Of course, other connection methods are also conceivable, e.g. glue or weld or press a purely mechanical.

Finally, the invention also relates to a system comprising a capsule filled with a substance as described above and a beverage preparation machine which has a capsule holder for receiving the capsule, and a device for passing a liquid through the capsule for extracting or dissolving the substance for producing a beverage , wherein the beverage preparation machine has at least one device for penetrating the bottom of the capsule. By using the capsules according to the invention in a beverage preparation machine known per se, their performance can be increased considerably. The additional openings in the base of the capsule reduce the load on the pump on the beverage preparation machine and thus extend its service life. Nevertheless, the capsule is absolutely aroma-tight and does not require an additional outer casing.

Further advantages in the system can be achieved in that the arrangement of the opening or the openings in the base of the capsule is adapted to the device for penetrating the base in such a way that at least one penetration means hits at least one opening. Depending on the configuration of the openings, an excellent flow rate can be achieved in this way.

Figur 1

Eine perspektivische Darstellung einer Kapsel,

Figur 2

Eine Draufsicht auf die Kapsel gemäss Figur 1,

Figur 3

Eine Draufsicht auf den leeren Kapselkörper gemäss Figur 1 in Richtung Kapselöffnung,

Figur 4

Einen Querschnitt durch den Kapselkörper gemäss Figur 3 in der Schnittebene A-A,

Figur 5

Einen Querschnitt durch den Kapselkörper gemäss Figur 3 in der Schnittebene B-B,

Figur 6

Ein vergrösserter Querschnitt durch einen Kapselboden mit eingesetzter Membran,

Figur 7

Eine schematische Darstellung der Herstellung eines Kapselkörpers,

Figur 8

Eine Draufsicht auf ein alternatives Ausführungsbeispiel einer Kapsel,

Figur 9

Eine Draufsicht auf ein weiteres Ausführungsbeispiel einer Kapsel, und

Figur 10

Ein vergrösserter Querschnitt durch einen Kapselboden mit durchgehend verbundener Membran.

Further advantages and individual features of the invention result from the following description of exemplary embodiments and from the drawings. Show it:

Figure 1

A perspective view of a capsule,

Figure 2

A top view of the capsule according to Figure 1 .

Figure 3

A top view of the empty capsule body according to Figure 1 towards the capsule opening,

Figure 4

A cross section through the capsule body according to Figure 3 in the section plane AA,

Figure 5

A cross section through the capsule body according to Figure 3 in the section plane BB,

Figure 6

An enlarged cross section through a capsule bottom with an inserted membrane,

Figure 7

A schematic representation of the manufacture of a capsule body,

Figure 8

A top view of an alternative embodiment of a capsule,

Figure 9

A top view of another embodiment of a capsule, and

Figure 10

An enlarged cross section through a capsule bottom with a continuously connected membrane.

According to Figure 1 A capsule 1 known per se consists of an essentially rotationally symmetrical capsule body 2 with a side wall 3 and a bottom 4. The capsule body 2 has the overall shape of a stepped truncated cone, the last truncated cone section 17 having the steepest truncated cone angle to the longitudinal central axis. The bottom 4 runs essentially flat, but may have a slightly concave curvature 25 in the central area for manufacturing reasons. Stiffening ribs 18 are arranged around the side wall 3 in a regular angular division. A circumferential flange 19 serves, on the one hand, for sealing in the beverage preparation machine and, on the other hand, for fastening a lid 5.

A stiffening zone 13, which is formed by individual indentations 14, adjoins the outer circumference of the base 4. These indentations interrupt the truncated cone section 17 in a regular angular division.

As especially from Figure 2 can be seen, 4 openings 8 are arranged in the form of slots in the bottom, which penetrate the bottom completely, but are closed in the idle state due to the material elasticity. In the embodiment shown, four slots are arranged at an angle of 90 ° each.

The Figures 3 to 5 show an empty capsule body 2 in the state before filling with a substance and before closing the capsule opening with the lid 5 for reasons of better clarity Figure 3 can be seen, the capsule bottom is covered on the inside with a membrane 9. The connecting zone 10, at which the membrane is firmly connected to the bottom, is indicated with an interrupted circular line. This connection zone follows the circumference of the floor and is circular in shape here.

The Figure 4 shows still further details of the stiffening zone 13 and the individual indentations 14. Each indentation is provided with an inner wall section 15 which in cross section runs approximately parallel to the longitudinal central axis of the capsule. The inner wall sections 15 lie on a common circumferential circle which corresponds approximately to the outer diameter of the membrane 9. Each indentation 14 also has over two side wall sections 16, the spacing of which widens slightly here towards the floor 4. In this way, particularly good stability is achieved against external force on the capsule base.

In Figure 5 the cross section through the truncated cone section 17 is shown in the left half of the figure. These are the sections between two individual indentations 14.

Figure 6 shows in a simplified representation the situation after the penetration of the capsule base 4 by a penetration means 12 in a beverage preparation machine. The membrane 9 is firmly connected to the capsule base 4 at an annular connection zone 10. This membrane consists of an aroma-tight film with barrier properties, for example made of aluminum. The capsule body 2 made of plastic material also has such an aroma-tight barrier layer, which is not shown in the drawings. The connecting zone 10 has an outer diameter d1, which at the same time corresponds approximately to the outer diameter of the membrane 9. However, the membrane 9 can also partially overlap the side wall 3 of the capsule. The inner diameter d2 of the connection zone 10 includes a central area 11, at which the membrane 9 is not firmly connected to the capsule bottom 4. The penetration means 12 penetrates the capsule base 4 and the membrane 9 inside or possibly also outside the central area 11. Hot brewing water flows through the opening 8, which can be a closed slot in the idle state, into the area between the capsule base 4 and the membrane 9 and from there through the opening in the membrane 9, which was created by the penetration means 12. At the same time, however, brewing water also penetrates through the opening in the bottom 4, which was also created by the penetration means 12. Before use in the beverage preparation machine, the chamber 6 formed by the capsule obviously remains hermetically sealed from the outside atmosphere.

The Figure 7 shows in individual sequences the production of a capsule body for a capsule according to the invention. First, according to a, a capsule body 2 is produced in a deep-drawing tool 20. The manufacturing technology and the materials are known to the person skilled in the art. For example, a film with multiple layers based on polypropylene and polyethylene can be used.

The finished capsule body 2 is provided according to b with the aid of a piercing tool 21 with the openings on the bottom.

A membrane 9 is then provided according to c and placed on the inside of the capsule body at the bottom.

According to d, the membrane 9 is then firmly connected to the bottom of the capsule body 2 in the manner described above using a heat sealing tool 22. The initially completely flat base of the capsule body can be given a slightly concave curvature against the inside by the sealing process. According to e, the capsule body 2 is filled with a substance 7 at a filling station 23, for example with coffee powder.

Finally, according to f, the capsule body 2 is closed with a lid 5 with the aid of a closing tool 24. In particular, work steps e and f can take place at a great distance from work step d. The prepared capsule bodies 2 can, for example, be stacked after the working step d and stored until they are fed to the filling station.

In the alternative embodiment according to Figure 8 the openings 8 consist of a total of eight circular holes which penetrate the bottom 4.

The capsule according to Figure 9 differs from that according to Figure 2 in that the four slots 8 serving as openings are arranged relatively far out almost in the region of the indentations 14. In such an arrangement, the openings are in the region of the connection zone, that is to say in the region in which the membrane 9 is firmly connected to the base 4 of the capsule. This is irrespective of whether the membrane is connected to the floor only at an annular connection zone or over the entire area.

Figure 10 shows an embodiment in which the membrane 9 is connected to the bottom 4 over the entire surface. The slot-shaped openings 8 here also extend far outside, as in FIG Figure 9 shown. The penetration means 12 and 12 'also penetrate the bottom 4 in the outer peripheral region of the bottom 4. The penetration means 12 shown penetrates the bottom in an area in which no opening is arranged. At this point there is no increase in the flow rate. In contrast, the penetration means 12 'penetrates the bottom 4 in an area in which an opening 8 is also arranged. Here, the slot 8 causes an increased flow rate, which is caused on the one hand by the enlarged opening cross section and on the other hand by a reduction in the resilience of the bottom wall.

Claims (16)

1. A capsule (1) having a capsule body (2) made of a plastics material, having a side wall (3) and having a base (4) formed in one piece therewith, and also having a cover (5) covering the capsule body in order to form a closed chamber (6) containing a substance (7) for the preparation of a beverage, wherein the capsule body (2) in the base (4) has at least one opening (8) for allowing a liquid to pass through the capsule, and in that a membrane (9) for sealing off the closed chamber with respect to the opening (8) is arranged on the inner side of the base (4), the membrane (9) is fixedly connected to the base (4) and consists of an aluminum-based film, characterized in that the capsule body (2) is a thermoformed part and in that the capsule body (2) and the cover (5) have barrier properties with respect to permeability of oxygen and flavorings and in that the membrane (9) likewise has barrier properties, and in that the membrane is connected to the base along a connection zone (10) following the circumference of the base, wherein the opening (8) is a slit that is closed in the pressureless state and that can be widened when exposed to hydraulic, pneumatic or mechanical pressure.
2. The capsule as claimed in claim 1, characterized in that the connection zone (10) encloses a central region (11) of the capsule base (4), in which the membrane (9) is not connected to the base.
3. The capsule as claimed in claim 2, characterized in that the opening (8) is arranged at least in part in the central region (11) of the capsule base (4), in which the membrane (9) is not connected to the base.
4. The capsule as claimed in one of claims 1 to 3, characterized in that the capsule (1) is rotationally symmetrical, and in that the connection zone (10) extends annularly.
5. The capsule as claimed in claim 4, characterized in that connection zone has an outer diameter between 14 and 17 mm and an inner diameter between 8 and 11 mm.
6. The capsule as claimed in claim 1, characterized in that the membrane is connected over its entire surface to the base (4).
7. The capsule as claimed in one of claims 1 to 6, characterized in that the membrane (9) is connected to the base by means of heat sealing.
8. The capsule as claimed in one of claims 1 to 7, characterized in that a number of openings (8), preferably at least three openings, are arranged in the base (4).
9. The capsule as claimed in one of claims 1 to 8, characterized in that the base (4) can be penetrated by penetration means for the passage of the liquid through the chamber in a beverage preparation machine, and in that the base at the outer circumference borders a reinforcement zone (13), which is formed by a number of indentations (14).
10. The capsule as claimed in claim 9, characterized in that the indentations (14) have inner wall portions (15) which lie on a common circular circumference, wherein the diameter of the circular circumference corresponds approximately to the diameter of the membrane (9).
11. A method for producing a capsule body (2) for a capsule (1), in particular as claimed in one of claims 1 to 10, characterized by the following steps:

    - providing a capsule body (2) produced in a thermoforming method using plastics material having at least one barrier layer, having a side wall (3) and having a base (4) formed in one piece therewith;

    - making at least one opening (8) in the base;

    - providing a membrane (9) having barrier properties, of which the surface configuration corresponds approximately to that of the base (4) ;

    - introducing the membrane (9) into the capsule body (2) and connecting said membrane to the inner side of the base (4) either along a connection zone (10) following the circumference of the base,

    wherein the opening (8) is formed without material removal by an incision in such a way that a slit that is self-closing in the rest state is produced.
12. The method as claimed in claim 11, characterized in that the base is formed as a flat surface.
13. The method as claimed in claim 11 or 12, characterized in that the opening (8) is punched out or burned out by means of laser beams.
14. The method as claimed in one of claims 11 to 13, characterized in that the membrane (9) is connected to the base (4) by heat sealing.
15. A system comprising a capsule (1) filled with a substance as claimed in one of claims 1 to 10 and comprising a beverage preparation machine, which has a capsule holder for receiving the capsule, and comprising an arrangement for allowing a liquid to pass through the capsule in order to extract or dissolve the substance in order to produce a beverage, wherein the beverage preparation machine has at least one device for penetrating the base (4) of the capsule.
16. The system as claimed in claim 15, characterized in that the arrangement of the opening or of the openings (8) in the base (4) of the capsule is adapted to the device for penetrating the base in such a way that at least one penetration means contacts at least one opening.

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