| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a soot detection device hardly influenced by a temperature change during evaluation, and having no risk of catalyst deterioration, and high measurement accuracy. <P>SOLUTION: A soot detection sensor 3 is used, wherein the first detection electrode 9 and a soot collection layer 21 in the first oxygen concentration measuring part 23 are constituted to be enterable by soot, and a soot restriction layer 27 for preventing entrance of soot is provided on the surface of the second detection electrode 11 of the second oxygen concentration measuring part 25. The temperature of the first oxygen concentration measuring part 23 is controlled at a temperature at which soot remains and soot can be burned (by pumped oxygen), and a voltage is applied in this state to the interval between both electrodes 9, 10 of the first oxygen concentration measuring part 23, and oxygen is pumped, and soot is burned at the temperature by using the pumped oxygen. An accumulation amount of the soot can be calculated from a difference between a current value I<SB>1</SB>between the electrodes 9, 10 of the first oxygen concentration measuring part 23 and a current value I<SB>2</SB>between electrodes 11, 12 of the first oxygen concentration measuring part 25. <P>COPYRIGHT: (C)2010,JPO&INPIT |
