| 摘要 |
The present invention relates to a brewing unit for a coffee machine. The brewing unit comprises a brewing chamber in which a dose of coffee powder can be lodged, an inlet for supplying water to the chamber for preparing a coffee beverage, a first piston providing a moveable wall for adjusting the chamber internal volume, which wall has an outlet for delivering the coffee beverage out from the chamber, and a valve assembly for opening/closing said delivery outlet. Advantageously a second piston is provided which moves the first piston and supports the valve assembly. The second piston is also moveable with respect to the first piston, for actuating the valve assembly. |
