摘要 |
In the disclosed ionization fire alarm structure, a gap that admits ambient air to the alarm test chamber eliminates directional smoke sensitivity or any insensitivity that might be caused by high air velocities. A ring shaped wall section in the approximate plane of the center electrode and common to the test and reference chambers, and an axially extending tubular wall and housing that enclose the jacket of a flat-bottomed external electrode establish the gap that admits ambient air to the test chamber and form axially compact device with adequate electrical insulation. An insulator cover and angular bends which are formed in the latch springs that couple the alarm to the base prevent unauthorized disassembly by requiring a special manipulation to uncouple these components.
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