Title:
NOISE CONTROLLER
Document Type and Number:
Japanese Patent JP3363254
Kind Code:
B2
Abstract:
PURPOSE: To stably muffle noise coming from the outside by constituting no electric loop in a noise control circuit and eliminating acoustic feedback from a control speaker.
CONSTITUTION: Plural noise detectors 21a-21n are provided on positions close to a noise source 1. The outputs of respective detectors pass through filters 22a-22n, and an addition signal is generated. First of all, a random sound of an oscillator 26 is radiated from the control speaker 4, and a total transfer characteristic of the filters 22a-22n is set so that an output becomes minimum. Then, switches 23, 25 are shifted to an input end (b), and a control sound becoming a phase opposite to the incoming noise in an error detector 3 is outputted from the control speaker 4.
More Like This:
| JP3522018 | NOISE CONTROLLER |
| JP3439789 | ACTIVE MUFFLER DEVICE |
Inventors:
Kenichi Terai
intermediate
Tadashi Tamura
Hiroyuki Hashimoto
intermediate
Tadashi Tamura
Hiroyuki Hashimoto
Application Number:
JP10211394A
Publication Date:
January 08, 2003
Filing Date:
April 15, 1994
Export Citation:
Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
F01N1/00; G10K11/178; H03H17/00; H03H21/00; (IPC1-7): G10K11/178; H03H17/00; H03H21/00
Domestic Patent References:
| JP5216485A | ||||
| JP5232968A | ||||
| JP635482A | ||||
| JP270195A |
Other References:
【文献】国際公開91/13429(WO,A1)
Attorney, Agent or Firm:
Yoshiki Okamoto