KNOCKING ACTIVATED DEVICE AND METHOD FOR OPERATING AN ELECTROMECHANICAL DEVICE RESPONSIVE TO A DEVICE CONTROL SIGNAL

摘要

A knocking activated device (10) and method for operating an electromechanical device that is responsive to a device control signal. The knocking activated device (10) amplifies a signal generated by a vibration transducer (18) according to an initial gain level that is momentarily decreased in response to a gain control signal received by a gain adjustable amplifier (15). Data that is representative of predetermined groups of knocks is stored in me mory (30), with each group not exceeding a predetermined maximum number of knocks. A microprocessor (28) discriminates the amplified signal into groups of knocks and carries out a comparison with the data stored in a memory (30) to produce the device control signal if the groups of knocks match the predetemined groups of knocks, whereas it generates the gain control signal if one group of knocks contains a number of knocks exceeding the predetermined maximum number of knocks.