JPS6257893U

JPS6257893U -

Info

Publication number: JPS6257893U
Application number: JP14814585U
Authority: JP
Priority date: 1985-09-30
Filing date: 1985-09-30
Publication date: 1987-04-10
Also published as: JPH0342551Y2

Description

[Brief explanation of the drawing]

第１図はこの考案のイオン化式煙感知器の一実
施例の縦断面図、第２図および第３図は第１図の
感知器が火災により天井面から落下した場合の外
部電極とシールドケースの状態を示す概略図であ
る。３……感知器基台、６……プリント基板、１０
……内部電極、１１……放射線源、１３……中間
電極、１５……外部電極、１６……小径部分、１
７……煙流入口、１８……大径部分、１９……係
止片、２０……脚片、２１……内部イオン室、２
２……外部イオン室、２３……シールドケース、
２４……蓋部、２５……椀部、２６……接続ピン
、２７……嵌挿口。 Figure 1 is a vertical cross-sectional view of one embodiment of the ionization smoke detector of this invention, and Figures 2 and 3 show the external electrode and shield case when the sensor in Figure 1 falls from the ceiling due to a fire. FIG. 3...Sensor base, 6...Printed circuit board, 10
...Internal electrode, 11...Radiation source, 13...Intermediate electrode, 15...Outer electrode, 16...Small diameter portion, 1
7... Smoke inlet, 18... Large diameter portion, 19... Locking piece, 20... Leg piece, 21... Internal ion chamber, 2
2... External ion chamber, 23... Shield case,
24... Lid part, 25... Bowl part, 26... Connection pin, 27... Fitting socket.

Claims

[Scope of Claim for Utility Model Registration] An inner and outer ion chamber having an inner electrode, an intermediate electrode, and an outer electrode, and a common radiation source for ionizing these ion chambers is provided in the inner ion chamber, and these are equipped with ICs or chip parts, etc. In the ionization type smoke detector, which is attached to a printed circuit board and is further provided with a metal shield case to cover these, the external electrode is composed of a cylinder having a large and small diameter. The shield has a bottom wall and a smoke inlet, and the upper edge of the large diameter part is provided with a locking piece that locks with the printed circuit board and a leg piece that holds the printed circuit board and the shield case at a constant interval. The case consists of a lid and a bowl that are fixed by fitting or caulking, and the lid has connection pins for attaching the printed circuit board to the sensor base, and the bottom of the bowl has the external electrodes. An ionization type smoke detector characterized in that a fitting opening is provided into which a small diameter portion of the ionization type smoke detector is fitted, and the height of the shield case made of these structures is lower than that of the external electrode.