Accident sound detector and accident sound detection device

摘要

PROBLEM TO BE SOLVED: To efficiently detect accident sound through the use of a threshold fluctuating in accordance with inputted acoustic signal level change as a reference signal by comparing the output of a reference signal generating means with the output of a delay adjusting means and generating an accident sound detecting signal in accordance with the comparison result. ;SOLUTION: A waveform reshaping circuit 50 reshapes the waveform of the acoustic signal 100 from a peripheral sound detecting device. A reference signal generating means consisting of an A/D converter 52b, a mobile average circuit 54, an adder 55 and a bias signal generator 56 executes a mobile average processing and bias level adjustment as against one of branched signals from the waveform reshaping circuit 50. A delay adjusting circuit 53 delays the other one of the branched signals from the waveform adjusting circuit 50 so as to execute delay and correction between outputs from the reference signal generating means. A comparing means consisting of D/A converters 57a and 57b and a comparator 58 compares the output of the reference signal generating means with the output of the delay adjusting circuit 53 and generates the accident sound detecting signal 140 in accordance with the comparison result.;COPYRIGHT: (C)1997,JPO