device for measuring concentration of explosive or toxic gases or for detecting the concentration of oxygen in the combustible gaseous mixtures

摘要

The sensor resistance (1) is arranged with three further : resistances (3,4,5) in a bridge circuit (6) fed with a constant current or voltage, and the diagonal branch of the bridge circuit is led to a signal output. The diagonal branch (7,8) is connected to a differential amplifier (9) and the output from the amplifier is connected to a transistor (11), the drain connection of which is connected to the positive input of the amplifier as well as to the assigned diagonal branch point (7) of the bridge circuit (6) and its working resistor (10) is connected to the signal output (12,13). An intermediate connected shunt regulating amplifier (9,10,11) is provided between the diagonal branch (7,8) and the signal output (12,13). USE/ADVANTAGE - Detector for detecting explosive or health risk gases or concn. of oxygen in combustible gas mixtures. Known type development, so that linearity of bridge signal depending on concn. of measured gas is improved.