JPS6258994U

JPS6258994U -

Info

Publication number: JPS6258994U
Application number: JP14992685U
Authority: JP
Priority date: 1985-10-02
Filing date: 1985-10-02
Publication date: 1987-04-11

Description

[Brief explanation of the drawing]

第１図は本考案を適用した自動車の車内のダツ
シユボードを示す図、第２図は第１図のフロント
ピラーの拡大図、第３図は第２図の矢印―断
面図、第４図は本考案に係る自動車電話用マイク
ロホンの一実施例を示す一部切欠組立斜視図、第
５図は本考案に係る自動車電話用マイクロホンの
電源回路の一実施例を示すブロツク図、第６図は
第５図に示すローパスフイルタの他の実施例を示
す回路図、第７図はマイクロホンのエンジン回転
数―騒音レベル特性を示すグラフである。２…フロントウインド、２ａ…フロントピラー
、４…フロントピラートリム、５…コンデンサ型
マイクロホン、６…弾性支持部材、１０…電源回
路、１１，２０…ローパスフイルタ、１２…定電
圧ＩＣ回路、１５…バツテリ、１６…オールタネ
ータ。 Fig. 1 is a diagram showing a dash board inside an automobile to which the present invention is applied, Fig. 2 is an enlarged view of the front pillar in Fig. 1, Fig. 3 is a sectional view taken along the arrow in Fig. 2, and Fig. 4 is a bookmark. 5 is a partially cutaway assembled perspective view showing an embodiment of the microphone for a car phone according to the invention; FIG. 5 is a block diagram showing an embodiment of the power supply circuit of the microphone for a car phone according to the invention; FIG. FIG. 7 is a circuit diagram showing another embodiment of the low-pass filter shown in the figure, and FIG. 7 is a graph showing the engine speed-noise level characteristic of the microphone. 2... Front window, 2a... Front pillar, 4... Front pillar trim, 5... Capacitor type microphone, 6... Elastic support member, 10... Power supply circuit, 11, 20... Low pass filter, 12... Constant voltage IC circuit, 15... Battery, 16...Alternator.

Claims

[Scope of utility model registration request]

A low-pass filter is connected between the battery and a constant voltage circuit that uses the battery of the vehicle as a power source and outputs a constant DC voltage to supply a constant DC voltage to the capacitor microphone of the car phone. A power supply circuit for a microphone for a car phone, characterized by: