| 摘要 |
<p>An automatic group for the preparation of one or more doses of expresso coffee comprises a rotating board (13) provided with through cylindrical holes (15-18) which in a first position of rotation of the board are fed with the dosed amount of fresh coffee powder, which is also pressed, and by the rotation of the board are brought to an infusion position and lastly to a position of discharge of the coffee grounds. In the infusion position, the pressed coffee powder, contained in the through hole of the rotating board, is vertically aligned in a tight manner with an above positioned shower (37) for the distributed feeding of hot water under pressure and with an under positioned filter (51) for the collection of the prepared expresso coffee; the space above and under said shower is into communication with said feed of hot water under pressure through a non return valve (44) having a calibrated opening pressure, which opens upon said tight seal between said board and said filter as well as with said collecting filter has been established under the action of the pressure of said hot feeding water, and through a relief valve (47) which opens in the absence of said pressure of the feeding water and under the action of the residual pressure under said feeding filter.</p> |
