Sensor for determining the thermal conductivity and/or temperature of liquid,gaseous or viscous substances and process for driving the sensor

摘要

A sensor is disclosed for determining the thermal conductivity and/or temperature of liquid, gaseous or viscous substances, for example engine oil. A process for driving the sensor is also disclosed. The sensor has a supporting body (1) and a measurement winding (7) of a type that reduces self-induction and inductivity. In order to create an appropriate sensor for determining the thermal conductivity and/or temperature of substances, the resistance wire (8) is uniformly arranged in an embedding space (9) provided for the measurement winding and having everywhere the same heat storage capacity, on a supporting body (1) of which each part has at the most the thermal capacity of a pair of adjacent resistance wire layers, so that the caloric medium temperature of the sensor may be sensed by means of the resistance wire (8). A predetermined cavity (10) for the substance to be examined is provided next to the sensor. The sensor is at first driven with a constant, low electric supply which is then changed to test the transmission behaviour of the sensor.