Coffee grinder with grinding adjustment system

An assembly comprising:

• a coffee machine comprising:
• a boiler for heating water;
• a dispensing unit suitable for accommodating a filter holder with a dose of ground coffee and dispensing hot water to extract the coffee;
• a heater connected to the boiler and to the dispensing unit to feed hot water to the dispensing unit suitable for extracting the coffee;
• a support arranged under the dispensing unit and suitable for supporting a cup intended to be filled with liquid coffee;
• a user interface comprising a display;
• a control unit connected to the user interface, and configured to detect a real extraction time (TE) equal to the time in which the cup is filled with a dose of liquid coffee;
• and
• a coffee grinder comprising:
• a hopper wherein coffee beans are contained;
• a grinder unit suitable for grinding the coffee beans to obtain coffee powder;
• an electric motor suitable for driving the grinder unit;
• an adjusting device suitable for adjusting a distance between the blades of the grinder unit;
• a slide for dispensing the ground coffee powder from the grinder unit;
• a support arranged under the slide and suitable for supporting a filter holder intended to be filled with a dose of coffee powder;
• a user interface comprising a display and buttons operable by the user, and an adjusting knob connected to the adjusting device and operable by the user to adjust the distance between the blades, and
• a control unit connected to the electric motor, to the adjusting device and to the user interface;
• wherein said user interface comprises:
• an initial configuration in which the user can enter an initial dose value (V0) to obtain a dose of coffee powder and an initial grind value (M0) indicative of the particle size of the coffee powder to be obtained;
• and
• a smart configuration in which the user can enter a target extraction time (TT) that is known to the user based on the recipe of the coffee to be obtained;
• wherein the control unit of the coffee machine is operatively connected to the control unit of the coffee grinder and configured to transmit said real extraction time (TE) to the control unit of the coffee grinder;
• and the control unit of the coffee grinder is configured to calculate a correction value (M) based on a difference (D) between the target extraction time (TT) and the real extraction time (TE), and operate said adjusting device based on said correction value (M).