Portable measurement instrument for the determination of gas content of air currents in under-land mines. (Machine-translation by Google Translate, not legally binding)

摘要

Portable measuring instrument for the determination of the gas content of the air currents in the underground mines with a calibrating chamber and a pump driven by a motor to aspirate an air sample, an electrical measurement circuit with indicator instrument and a circuit Consecutive electric time for the pump maneuver and the connection of the rated voltage for the measuring circuit, characterized in that said consecutive time circuit contains an additional time stage, by which the connection of the rated voltage for the measuring circuit it is deferred, in relation to the end of the suction process and to the disconnection of the pump, in an adjustable time frame. (Machine-translation by Google Translate, not legally binding)