| 摘要 |
<p>PURPOSE: To effect ignition and recuperation within a narrow control range so as to increase the durability of a filter trap by radiating a microwave signal of a predetermined frequency to the filter trap to determine an effective dielectric loss ratio of trapped particle-shaped material, and determining the trap quantity from the temperature of the filter trap and effecting combustion when a predetermined trap quantity is reached. CONSTITUTION: Exhaust gas from an engine is trapped by a filter trap 16. A microwave signal of a predetermined frequency is supplied to a transmission antenna 20. A microwave attenuated in response to the quantity of particle material deposited in the filter trap 16 is received by a receiving antenna 30, corrected in a temperature correcting circuit 71 according to the measured value of a thermocouple 73 (temperature sensor), and compared with a reference signal in a comparator 70. A switch 74 is turned on when the two signals reach a certain value to actuate an electric motor 72. Thus, the soot in the filter trap is ignited and combusted. In this way, it is possible to effect ignition and recuperation within a narrow control range so as to increase the durability of the filter trap.</p> |
