JPH0386698U

JPH0386698U -

Info

Publication number: JPH0386698U
Application number: JP14915589U
Authority: JP
Priority date: 1989-12-25
Filing date: 1989-12-25
Publication date: 1991-09-02

Description

[Brief explanation of the drawing]

第１図は本考案第１実施例のアクテイブ・ノイ
ズ・キヤンセラーの構成を示す全体図、第２図は
第１実施例アクテイブ・ノイズ・キヤンセラーに
よるキヤンセル音並びに負キヤンセル音及び外部
騒音を示す特性図、第３図は本考案第２実施例の
アクテイブ・ノイズ・キヤンセラーを示す全体図
である。１……消音スピーカ、１ｅ……ダイヤフラム表
面（正圧面）、１ｆ……ダイヤフラム裏面（負圧
面）、２……副スピーカ、２ｅ……ダイヤフラム
表面（正圧面）、２ｆ……ダイヤフラム裏面（負
圧面）、３……モニタ用マイクロホン、４……騒
音キヤンセル回路、４ａ……プリアンプ（ゲイン
変更手段）、７……ゲイン判断回路、８……フイ
ードバツク用マイクロホン、２４……騒音キヤン
セル回路、２４ｆ……処理回路（ゲイン変更手段
）、２７……ゲイン判断回路。 Fig. 1 is an overall diagram showing the configuration of the active noise canceller of the first embodiment of the present invention, and Fig. 2 is a characteristic diagram showing the cancel sound, negative cancel sound, and external noise by the active noise canceller of the first embodiment. , FIG. 3 is an overall view showing an active noise canceller according to a second embodiment of the present invention. 1... Silence speaker, 1e... Diaphragm surface (positive pressure side), 1f... Diaphragm back surface (negative pressure side), 2... Sub speaker, 2e... Diaphragm surface (positive pressure side), 2f... Diaphragm back surface (negative pressure side) ), 3...Monitor microphone, 4...Noise cancel circuit, 4a...Preamplifier (gain changing means), 7...Gain judgment circuit, 8...Feedback microphone, 24...Noise cancel circuit, 24f... Processing circuit (gain changing means), 27...Gain judgment circuit.

Claims

[Claims for Utility Model Registration] A silencing speaker that emits a predetermined cancel sound from a positive pressure side toward a silencing space, and a sub-speaker provided on the negative pressure side of the silencing speaker with one of its positive and negative surfaces facing each other. , a monitor microphone that is placed at a position where the sounds emitted from both speakers cancel each other out and inputs the sound to be silenced; and a cancel sound that is in the opposite phase to the input sound of the monitor microphone is emitted from the positive pressure side of the silencer speaker. a noise cancel circuit that outputs a cancel sound generation signal to cause the noise canceling space to emit, and a sub cancel sound generation signal to cause the sub speaker to radiate a sub cancel sound having the same phase as the cancel sound to the negative pressure surface of the silence speaker; a feedback microphone that inputs the sound; a gain determination circuit that determines whether the output gain of the cancel sound is appropriate based on the input of the feedback microphone; and a gain determination circuit that determines whether the output gain of the cancel sound is appropriate based on the input of the feedback microphone; An active noise canceller comprising: gain changing means capable of changing the zein of both cancel sound generation signals of a cancel circuit;