Method for counting the number of turns of the grinding wheel of a coffee grinder and device comprising such a grinder

摘要

The method involves measuring electric parameter e.g. electric current requirement, of an electric motor at regular time interval, where the parameter varies proportional to a speed of the motor. The motor is supplied with alternating current or direct current. The speed on each regular time interval is calculated from an experimentally obtained relation. The number of turns carried out by a grinding wheel on each time interval is calculated from the calculated speed. An independent claim is also included for a coffee preparing apparatus comprising a coffee grinder provided with a grinding wheel.