Title:
SOUND-PROOF DEVICE
Document Type and Number:
Japanese Patent JP3275486
Kind Code:
B2
Abstract:
PURPOSE: To output the sounds of an opposite phase from the phase of the noises outside a sound-proof chamber from sound waves generating means and drastically decrease the noises in this sound-proof chamber by phase interference of the sound waves.
CONSTITUTION: The sound-proof chamber 11 having apertures of an inlet part 12 and an outlet part 13 is provided with first pressure detectors 14, 15 for detecting the pressure outside the sound-proof chamber and second pressure detectors 17, 18 for detecting the pressure in the sound-proof chamber. The inside of the sound-proof chamber is provided with an arithmetic unit 19 for calculating the sound wave signals with which the pressure near the second pressure detectors 17, 18 is suppressed by the opposite phase interference by the sound waves in accordance with the signals of the first pressure detectors 14, 15 and the signals of the second pressure detectors 17, 18 and the sound wave generating means 20, 21 for generating the sound waves. As a result, the noises are drastically decreased by the phase interference of the sound waves.
Inventors:
Yasuhiro Umekage
Masamitsu Kondo
Masamitsu Kondo
Application Number:
JP26873093A
Publication Date:
April 15, 2002
Filing Date:
October 27, 1993
Export Citation:
Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
E04H1/12; E04H5/02; G10K11/178; (IPC1-7): G10K11/178; E04H1/12; E04H5/02
Domestic Patent References:
| JP342999A | ||||
| JP5279903A | ||||
| JP561489A | ||||
| JP6240776A | ||||
| JP764571A | ||||
| JP75199U | ||||
| JP334261U |
Attorney, Agent or Firm:
Fumio Iwahashi (2 others)
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