Machine for infusion preparation, in particular espresso coffee, supplying group and manufacturing method thereof

A supplying group for an espresso coffee machine, comprising:

• a first chamber arranged to contain a certain amount of liquid and connected to a boiler;
• and
• a second chamber arranged inside the first chamber and hydraulically connected to the first chamber by an outlet duct of the first chamber and an inlet duct of the second chamber,
• wherein the first chamber comprises a first chamber heating element distributed inside the entire first chamber or inside a portion of the first chamber and arranged to directly heat the liquid contained in the first chamber to an infusion temperature for espresso coffee preparation,
• wherein the second chamber is provided for being filled with liquid hydraulically received from the first chamber by the outlet duct and the inlet duct and heated by the first chamber heating element, the second chamber being connected by a second outlet duct to an external filter holder for infusion preparation, and
• wherein a valve is provided between the outlet duct and the inlet duct, the valve being arranged to deliver the liquid, heated by the first chamber heating element, from the first chamber to the second chamber and to the second outlet duct for infusion preparation at the infusion temperature for espresso coffee preparation.

An espresso coffee machine for preparing espresso coffee, comprising in a body:

• a first heating unit that heats a liquid;
• at least one supplying group connected through a first duct to the first heating unit, the at least one supplying group comprising:
• an accumulation chamber with an inlet for receiving through the first duct the liquid heated by the first heating unit;
• a second heating unit contained within the accumulation chamber;
• an internal chamber hydraulically connected to the accumulation chamber and arranged to be fed by the accumulation chamber with supply water by an outlet duct exiting from the accumulation chamber and an inlet duct entering the internal chamber during the process of preparing an espresso coffee beverage;
• wherein the internal chamber is contained within the accumulation chamber;
• wherein the second heating unit is distributed inside the entire accumulation chamber or inside a portion of the accumulation chamber and is arranged to heat the supply water to an infusion temperature optimized for espresso coffee preparation,
• wherein a valve is provided between the outlet duct and the inlet duct, the valve being arranged for delivering the liquid, heated by the second heating unit, from the accumulation chamber to the internal chamber for infusion preparation at the infusion temperature optimized for espresso coffee preparation;
• and
• wherein the at least one supplying group is associated with a respective filter holder containing, in use, coffee powder and equipped with respective spouts, whereby the internal chamber is configured to supply the hot liquid to the filter holder through a second outlet duct for preparing espresso coffee at the infusion temperature optimized for espresso coffee preparation.