| 摘要 |
PROBLEM TO BE SOLVED: To provide a muffling unit which can be applied to an existing object device to effectively muffle drive sound caused by an object device. SOLUTION: This thin muffling unit 100 is composed by arranging a microphone 102A and a speaker 103A on the front face of a main body 101 which can be installed in a space S formed between a vending machine 1 and an installation face 200, which is relatively low in height. A sound signal is generated so that a sound from the speaker 103A to be input to the microcomputer 102A can have an anti-phase to the phase of a drive sound generated by the vending machine 1 to be input to the microcomputer 102A. Thus, it is possible to make the sound from the speaker 103A interfere with the drive sound, and to muffle the drive sound. COPYRIGHT: (C)2009,JPO&INPIT
|
