Micro gas sensor has a heated filter, in front of the heated gas sensor, with a micro pump to generate intermittent gas flows and a flow sensor to register flow speeds

摘要

The micro gas analysis system (10), with a heated filter (13), has a gas sensor (12) to detect a gas or a gas mixture. The filter is in front of the sensor, in the gas flow direction (A), with separation between them. A heater (14) heats the filter, and a further heater heats the sensor. A control is connected to both heaters, to modulate the filter and sensor temperatures independently. A micro pump (18) generates an intermittent gas flow, and a flow sensor (24) registers the gas flow speed. A lock-in amplifier is used for evaluation.