Apparatus for preparing a beverage and a decoction device

1. An apparatus for preparing a beverage, comprising a decoction device for performing a beverage preparation cycle, said decoction device comprising a decoction body having a decoction chamber that is surrounded by a chamber wall and that extends axially between a first bottom and a second bottom of said decoction device that lie opposite each other,

wherein said first bottom and said second bottom are received for axial movement inside said chamber wall,

wherein said chamber wall is provided locally with a filling opening for admitting into the decoction chamber at least one ingredient for the beverage to be prepared,

wherein the decoction chamber is provided with an inlet for admitting a liquid under increased pressure and temperature,

wherein the decoction chamber is provided with a dispenser for dispensing a beverage prepared from the liquid and the at least one ingredient,

wherein the decoction device further comprises a drive mechanism coupled to the decoction body and wherein the apparatus further comprises a motor configured to power the drive mechanism,

wherein the decoction body is driven during operation by the driving mechanism to impart said preparation cycle to the decoction device, said preparation cycle comprising:

a first state in which the filling opening opens into the decoction chamber and is situated between said first bottom and said second bottom;

a second state in which said first bottom and said second bottom have moved closer to each other inside the chamber wall and the liquid is guided through the decoction chamber;

a third state in which a space between said first bottom and said second bottom lies next to the chamber wall exposing a possible residue of said at least one ingredient thus allowing the decoction chamber to get rid of said residue,

wherein said first bottom and said second bottom are both located at a first side of said filling opening in said second state,

wherein said first bottom and said second bottom are both located at said first side of said filling opening in said third state, and

wherein moving said decoction device from said second state into said third state comprises driving said chamber wall of said decoction body in a first direction, away from said first bottom and said second bottom, and over at least one of said first bottom and said second bottom, until said space between said first bottom and said second bottom lies at said first side of said filling opening outside said chamber wall.

2. The apparatus as claimed in claim 1 ,

wherein, during operation, said first bottom and said chamber wall both carry out a first stroke in said first direction while the decoction device is driven from said first state into said second state,

wherein between the second state and the third state the chamber wall carries out a second stroke in said first direction which moves the chamber wall away from the first bottom, and

wherein said chamber wall carries out a third stroke in a second direction, opposite said first direction, towards the first bottom to return the decoction device to the first state.

3. The apparatus as claimed in claim 2 , wherein the first bottom is subjected to a displacement in the second direction while the decoction device moves from the second state to the third state, driving the first bottom and the second bottom apart.

4. The apparatus as claimed in claim 1 , wherein in the second state the first bottom has moved closer to the second bottom axially in the first direction.

5. The apparatus as claimed in claim 2 , wherein said first bottom is part of a bottom body, wherein the drive mechanism engages on said bottom body, and wherein a transmission is provided between the bottom body and the chamber wall.

6. The apparatus as claimed in claim 5 , wherein the drive mechanism comprises at least one screw spindle which engages in a threaded aperture in the bottom body.

7. The apparatus as claimed in claim 5 , wherein the transmission comprises a gear ring which extends for rotation about a rotation shaft and engages on a toothing that is axially straighter than the gear ring.

8. The apparatus as claimed in claim 7 , wherein in the second stroke, during which the chamber wall and the first bottom are driven apart, the gear ring is set into a first rotation about the rotation shaft, and that in the third stroke, during which the decoction device returns to the first state, the gear ring performs a second rotation in an opposite direction about the rotation shaft whereby the chamber wall and the first bottom are brought together.

9. The apparatus as claimed in claim 2 , wherein the first bottom is rotatable about a central axis inside the decoction chamber and the drive mechanism is coupled to the first bottom in order to set this bottom into a rotation about the central axis during the first stroke.

10. The apparatus as claimed in claim 1 , wherein the first bottom at least partially comprises the inlet and the second bottom at least partially comprises the dispenser.

11. The apparatus as claimed in claim 1 , wherein an ejector is provided which is able and configured, when actuated in the third state, to displace a residue of the ingredient possibly remaining between the two bottoms.

12. The apparatus as claimed in claim 11 , wherein the ejector comprises an arm which is arranged close to an outer end of the decoction body for rotation about a shaft and which outside the third state is carried into a starting position and acquires a bias, and in the third state is released in order to swing between the two bottoms.

13. The apparatus as claimed in claim 6 , wherein said at least one screw spindle comprises a first screw spindle that engages a first threaded aperture at a first side of said pair of bottoms and a second screw spindle that engages a second threaded aperture at a second side of said pair of bottoms, said second side being opposite said first side, and wherein said first and second screw spindle are received to the respective side of the second bottom in a second bottom body that comprises the second bottom.

14. The apparatus as claimed in claim 7 , wherein said toothing is a linear toothing.