Patent ID: 8733233

Claim:
Machine for preparing coffee comprising an infusion chamber to house at least a coffee dose, and means for feeding pressurized water to said infusion chamber ( 8 ), said means comprising a cylinder ( 2 ) and plunger ( 3 ) assembly, said plunger ( 3 ) defining inside the cylinder ( 2 ) a chamber ( 6 ) to house a preset quantity of water, and said plunger ( 3 ) being able to accumulate, in an active position, potential energy capable of being transmitted as a pressure to the water of said chamber ( 6 ), when said plunger ( 3 ) contacts, in said active position, with the water of said chamber ( 6 ), wherein said plunger ( 3 ) accumulates its potential energy from the compression force applied to one of a fluid and a spring, said compression force being applied when said plunger ( 3 ) is retracted in the chamber ( 6 ) of the cylinder ( 2 ), and wherein said infusion chamber ( 8 ) is placed adjacent below the water chamber ( 6 ) of said cylinder ( 2 ), both chambers including at least one hole ( 10 ) with a passage valve through which, once opened, passes the pressurized water to said infusion chamber ( 8 ), said plunger ( 3 ) moving back to the rest position inside said chamber ( 6 ) as pressurized water is fed through said hole ( 10 ).