JPS596291U

JPS596291U - gas alarm device

Info

Publication number: JPS596291U
Application number: JP9948382U
Authority: JP
Inventors: 満治吉良; 隆司山口; 砂原　将三郎
Original assignee: フイガロ技研株式会社
Priority date: 1982-06-30
Filing date: 1982-06-30
Publication date: 1984-01-14

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

第１図はこの考案の１実施例の回路図で、第２図ａ、　
　ｂは素子の抵抗値と、定電圧回路の出力、自己発熱量
および素子の温度との関係を示す特性図、第３図は素子
の特性図、第４図はガス濃度と素子の温度との関係の特
性図、第５図はガス濃度と出力との特性図である。第６
図は他の実施例の回路図、第７図はその実施例での素子
の抵抗値と自己発熱量との特性図である。３・・・自己発熱形ガス検出素子、１１・・・定電圧回
路、２１・・・負荷要素、Ｒ１，Ｒ２，Ｒ４・・・負荷
抵抗、３１・・・警報手段、３４・・・ブザー、４１．
７４・・・自己発熱制御手段、５し・・検出回路、６１
・・・比較回路、ｚｌ、ｚ２・・・ツェナーダイオード
、Ｔｒｌ・・・制御用トランジスタ、Ｃ１・・・発振防
止用コンデンサ、ＤＩ、Ｄ２・・・ダイオード。第２図 −半−ｍ−］１＃”ｅｌ　ｌ　ｌ　ＩＩ　剛■− し１羽はｌに−、、、１Figure 1 is a circuit diagram of one embodiment of this invention, and Figure 2 a,
b is a characteristic diagram showing the relationship between the resistance value of the element, the output of the constant voltage circuit, the amount of self-heating, and the temperature of the element, Figure 3 is the characteristic diagram of the element, and Figure 4 is the relationship between the gas concentration and the temperature of the element. FIG. 5 is a characteristic diagram of the relationship between gas concentration and output. 6th
The figure is a circuit diagram of another embodiment, and FIG. 7 is a characteristic diagram of the resistance value and self-heating amount of the element in that embodiment. 3... Self-heating type gas detection element, 11... Constant voltage circuit, 21... Load element, R1, R2, R4... Load resistance, 31... Alarm means, 34... Buzzer, 41.
74... Self-heating control means, 5... Detection circuit, 61
... Comparison circuit, zl, z2 ... Zener diode, Trl ... Control transistor, C1 ... Oscillation prevention capacitor, DI, D2 ... Diode. Fig. 2 - Half-m-] 1#"el l l II Tsug ■- and one bird is l-,,,1

Claims

[Scope of utility model registration request]

A gas detection element, which has a pair of electrodes connected to a gas ridge-sensitive N-type metal oxide semiconductor, is powered by a power source so that the element automatically heats up in gas at a concentration that should cause an alarm due to self-heating generated by the detection current to the element. and a load element are connected in series, and an alarm means is provided to issue an alarm when the resistance value of the element becomes less than or equal to a predetermined value, wherein the resistance value of the element is greater than or equal to another predetermined value that is greater than or equal to the predetermined value. What is claimed is: 1. A gas alarm device comprising a self-heating control means that operates to reduce a detected current to an element.