| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect a PM (particular matter) quantity in exhaust gas of an internal combustion engine in high accuracy. <P>SOLUTION: A PM sensor is installed in a sensor case into which part of exhaust gas flowing in an exhaust passage is taken. A part of a wall surface of the sensor case is heated by heat of the exhaust gas flowing in the exhaust passage and a heater for the case to generate a temperature difference in the sensor case and the PM in the exhaust gas in the sensor case is guided to the PM sensor by a thermophoresis effect caused by the temperature difference. When the temperature of the exhaust gas flowing in the exhaust passage is low, an output of the heater for the case is set higher than that when the temperature of the exhaust gas is high. <P>COPYRIGHT: (C)2012,JPO&INPIT |
