| 摘要 |
PROBLEM TO BE SOLVED: To provide a space-saving vending machine eliminating driving noise in the machine. SOLUTION: An opening/closing door 3 is provided with a microphone 24 and a loudspeaker 23, and an internal space 26 is formed in the opening/closing door 3. A sound signal is generated so that sound input to the microphone 24 from the loudspeaker 23 has a reverse phase with respect to the driving noise in a casing. Sound from the loudspeaker 23 thereby interferes with the driving noise to eliminate the driving noise. Since the internal space 26 is formed in the opening/closing door 3, the opening/closing door 3 forms an enclosure for the loudspeaker 23. The space in the opening/closing door 3 can thereby be effectively used without preparing such a space in a casing 2. COPYRIGHT: (C)2008,JPO&INPIT
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