| 摘要 |
PURPOSE:To control the magnitude of a vibration, to reduce an energy consumption, and to lengthen the lifetime of a battery by using a loudspeaker as a microphone and interruptively operating a vibrator corresponding to the degree of a surrounding noise. CONSTITUTION:A surrounding noise component collected by a loudspeaker 32 used also as a microphone is amplified by a preamplifying circuit, it is converted to a direct current signal by an A-D converting circuit 31, a voltage to be temporarily held by a holding circuit 27 is inputted to a comparator circuit 26, and it is converted to a digital signal. A control circuit 22 sends the successive direct current signal or an interruptive signal to a vibrator driving circuit 14 based on the signal outputted from the comparator circuit 26, and the circuit 22 controls the motor rotation frequency of a vibrator 15. Namely, when the noise detected by the loudspeaker 32 is small, the motor rotation frequency is lowered and the vibration is weakened in order to cause an abnormal sound generation to be as small as possible. Thus, the energy consumption can be reduced. |
