NOISE REDUCTION DEVICE

PROBLEM TO BE SOLVED: To provide a noise reduction device permitting to obtain a sufficient silencing effect at any time even to changes in noise frequencies caused by environmental changes and lapse of time without resulting in an increase in the cost and the device development time. SOLUTION: By making a drive control signal for controlling operation of a mechanism part 20 correspond to a noise data that is generated by the operation of the mechanism part from the drive control circuit, detected by a noise detecting means 40 such as a microphone, etc., and converted into a digital noise, storing the noise in a storage means 70 such as a memory, etc., reading the noise data made to correspond to the drive control signal from the storage means, always detecting an amplitude level of noises being generated at that time of generating a muffling signal of the same amplitude and anti- phase noise as is generated from the mechanism part on the basis of the noise data and the amplitude level of the muffling noise, adjusting and outputting the amplitude of the muffling sound so that it has a best muffling effect by comparing both amplitude levels with each other, and thus, this noise muffling device is enabled to output muffling sound of a same amplitude as that of the noise being generated at the point in time as far as possible.