Patent ID: 7481152
Filing Date: 2009-01-27
Classification: A47J

Abstract:
1. A brewing unit for a coffee machine comprising: a brewing cylinder and at least one piston wherein the brewing cylinder and the piston are movable relative to one another in an axial direction; an activatable seal assembly for sealing the piston against an inner wall of the brewing cylinder; said seal assembly being activated by being placed in compression by an axial movement of at least a part of a piston with respect to the brewing cylinder to form a seal between piston and brewing cylinder inner wall; said seal assembly when not activated being in at most minimal contact with the inner wall being moved relative to the seal assembly; wherein in a brewing position of pistons and brewing cylinder, a first piston is held in place by a backside of a first piston bottom pressing on an inwardly projecting annular section of the brewing cylinder with the sealing assembly located between the first piston bottom and the annular section; and wherein the sealing assembly moves at most only minimally in the axial direction relative to a support for sealing assembly.