Percolating machine for producing a beverage using a sealed capsule of anhydrous powdered material

A percolating machine for producing a beverage using a sealed capsule containing anhydrous powdered material and defined by a cup-shaped body closed at one end by a bottom wall and at another end by a sealing wall fitted integrally to the cup-shaped body;

• the machine comprising:
• a pressurized-hot-water dispenser having an end wall;
• a removable percolating cup for housing a said capsule, and positioned, in use, with its inlet facing said end wall;
• supporting and retaining means for retaining said percolating cup, in use, in a work position connected to said end wall;
• a first piercing device carried by said sprinkler to permit pressurized-hot-water flow through said sealing wall;
• and
• a second piercing device carried by said percolating cup to permit outflow of said beverage through said bottom wall;
• wherein the dispensing means, the supporting and retaining means and the percolating cup are aligned, in use, along an axis;
• wherein said first piercing device comprises a number of projections extending toward said supporting and retaining means from a peripheral portion of said end wall and equally spaced about said axis in a single circle coaxial with said axis and of a diameter approximately equal to but no larger than an inside diameter of said inlet;
• and
• wherein each projection of the first piercing device has a substantially rectangular base having a first side facing said axis and a second side facing away from said axis, and a substantially saw-tooth profile having an inclined first surface extending along the first side, and a part-cylindrical second surface coaxial with said axis extending along the second side and intersecting the first surface to define a cutting edge.