Capsule for an extraction product, method for the production thereof, and device for brewing coffee
A capsule to form a closed interior filled with an extraction product or extract can be perforated in a known manner by perforation elements of an injection device or a discharge device in order to introduce an extraction liquid and to discharge an extraction product produced in the interior of the capsule following an extraction process. The capsule has the shape of a cuboid or a die.
1. A portion capsule for a coffee machine, comprising:
a capsule wall, the capsule wall enclosing a closed interior space that is filled with an extraction material, said capsule wall being adapted to be perforated by perforating elements of an injector device or discharge device upon closing of a brewing chamber of the coffee machine so as to introduce an extraction liquid under pressure into the capsule and to discharge an extraction product produced inside the capsule after a brewing operation, the capsule being designed to be under positive pressure during the brewing operation and to be capable of withstanding the extraction liquid being under positive pressure
wherein the capsule, except for a peripheral edge that laterally protrudes by a maximum of 1.5 mm, has a form of a cube or cuboid;
wherein the capsule wall is formed by a five-sided basic body that is open on a sixth side and by a cover closing off the basic body, and wherein cover is outwardly curved and the basic body and the cover are joined at the peripheral edge, whereby the peripheral edge between the cover and the basic body is offset from an upper end face of the capsule.
2. The capsule according to claim 1 , wherein the capsule is cube-shaped.
3. The capsule according to claim 2 , wherein the capsule can be pierced from every pair of opposite sides of the cube.
4. The capsule according to claim 1 , wherein the capsule comprises essentially a same material composition and is of essentially a same thickness on all six sides.
5. The capsule according to claim 1 , wherein the capsule is capable of being compressed in a volume-reducing manner by pressure on a central point on each of two opposite side walls counter to an elastic opposing force.
6. The capsule according to claim 1 , wherein a wall thickness of the capsule wall is between 0.1 mm and 0.5 mm.
7. The capsule according to claim 1 , wherein the capsule consists of plastic, preferably of polypropylene.
8. The capsule according to claim 7 , wherein at least five of its six sides are produced by deforming a sheet of plastic.
9. The capsule according to claim 1 , said capsule being closed off in a hermetic and oxygen-tight manner by the capsule wall comprising all sides, edges and corners.
10. The capsule according to claim 1 , said capsule being entirely free from filtering means and other elements arranged between the wall and the extraction material so that the extraction material can lie directly against each side.
11. The capsule according to claim 9 , said capsule being entirely free from filtering means and other elements arranged between the wall and the extraction material so that the extraction material can lie directly against each side.
12. A method for producing a capsule having a capsule wall, the capsule wall enclosing a closed interior space that is filled with an extraction material, said capsule wall being adapted to be perforated by perforating elements of an injector device or discharge device upon closing of a brewing chamber of the coffee machine so as to introduce an extraction liquid under pressure into the capsule and to discharge an extraction product produced inside the capsule after a brewing operation, the capsule being designed to be under positive pressure during the brewing operation and to be capable of withstanding the extraction liquid being under positive pressure,
wherein the capsule, except for a peripheral edge that laterally protrudes by a maximum of 1.5 mm, has a form of a cube or cuboid,
wherein the capsule wall is formed by a five-sided basic body that is open on a sixth side and by a cover closing off the basic body, wherein the cover is outwardly curved and the basic body and the cover are joined at the peripheral edge, whereby the peripheral edge between the cover and the basic body is offset from an upper end face of the capsule, and wherein at least five of its six sides are provided by deforming a sheet of plastic, the method comprising the steps of:
producing a five-sided basic body that is open on a sixth side by thermoforming,
filling the basic body with an extraction material or extract;
fastening a cover along a peripheral edge of the open sixth side such that the interior space produced is completely enclosed.
13. The method according to claim 12 , wherein the basic body is produced such that it is provided with a collar arranged along the peripheral edge and in that, during the fastening of the cover, the cover is welded or adhesively bonded to the basic body at the collar.
14. The method according to claim 13 , wherein, during the welding or adhesive bonding, the collar is supported on a contact surface.
15. The method according to claim 13 , wherein the cover is fastened to the basic body by means of ultrasonic welding.
16. The method according to claim 15 , wherein during the ultrasonic welding, the collar is at the same time detached by the effect of the ultrasound.