| 摘要 |
<p>1. A fire detector equipped with a reference element and an analysing element which is constituted by an open radioactive ionization chamber (1) the impedance of which varies in the presence of combustion gases, said elements being coupled in a bridge and connected to two inputs of two voltage comparators (A1 and A2) each connected to an alarm system (S1, S2) such that imbalance of the bridge produces a signal at the output of one or other comparator depending on the direction of the imbalance and operates the corresponding alarm system, characterized in that the voltage applied at the terminals of the analysing chamber lies within the so-called recombination zone of its curve for ionization current as a function of the voltage applied.</p> |
