摘要 |
<P>PROBLEM TO BE SOLVED: To restrain biasing of the adhering position of PM in a honeycomb structure. <P>SOLUTION: The frequency of applied voltage to counter electrodes 50a, 50b for controlling an electric field is controlled to be higher as the rotational frequency of an engine becomes higher. The moving path of a PM is controlled by the action of the counter electrodes 50a, 50b, and adhesion of the PM in the honeycomb structure 20 can be made uniform by periodic variation of applied voltage. Since the frequency of applied voltage is changed according to the rotational frequency of the engine, even if the flow rate of exhaust emission or harmful matter concentration is high, the frequency is made higher according thereto, thereby further homogenizing adhesion. <P>COPYRIGHT: (C)2005,JPO&NCIPI |