SYSTEM AND METHOD FOR DETERMINING THE RESONANT FREQUENCY OF AN OSCILLATING APPLIANCE, IN PARTICULAR A POWER TOOTHBRUSH

摘要

A system and corresponding method for determining the frequency and/or amplitude of an oscillating apparatus, which includes a driving assembly having a stator portion and an armature portion, and a driving signal circuit which supplies a driving signal to the stator portion. A control circuit interrupts the drive signal momentarily, for at least a quarter of a cycle, at periodic intervals, resulting in a signal being induced into the stator coil from continuing movement of the armature. A measurement/read circuit is connected to the stator coil for determining one or both of the frequency of the induced signal and the amplitude of the induced signal. The frequency or amplitude information is then compared against pre-established values and any differences are used to change the driving signal so as to provide maximum performance of the appliance.