Brewing apparatus for a coffee machine

Abstract

A brewing apparatus has a brewing cylinder (1) with a cylindrical bore (2) and two pistons (3, 4). The brewing cylinder (1) and the pistons (3, 4) are disposed displaceably relative to one another. In a brewing position the brewing cylinder (1) and the two pistons (3, 4) within the latter form a brewing chamber (5) in order to scald ground coffee therein through the feed of pressurized water. This water is fed to the brewing chamber (5) via a connection fitting (18) and via a through bore which extends through the wall of the brewing cylinder (1), into an annular gap (14) which is formed between a gasket (11) and the end face (13) of the second piston (4) facing the brewing chamber (5). Via a strainer (32), a conduit (34), and a further connection fitting (35), the coffee is discharged. Through the arrangement of the gap (14), the face (13) of the second piston ( 4) can be made without a strainer. The feeding of pressurized water to the gap (14) causes a self-cleaning effect in the latter. Through the strainer-less design of the end face (13) of the second piston (4), not only can a wearing part be eliminated, but a more cost-effective manufacture of the brewing apparatus can also be carried out.

Dependencies are inferred from the claim text.