| 摘要 |
An object of the invention is to enhance the exhaust gas purification rate and to reduce the possibility of breakage of a heater element in an electric heating catalyst (EHC) by generating heat by the heater element in a improved manner. A pair of electrodes including surface electrodes 7a extending in the axial and circumferential directions of the heater element along the outer circumferential surface of said heater element are provided in such a way as to be opposed to each other on the heater element located therebetween. The surface electrodes 7a are adapted in such a way that current flowing between the surface electrodes 7a flows mainly on the outer circumferential surface of the heater element in a part of the heater element with respect to the axial direction and flows mainly in an inner portion of the heater element in another part of the heater element with respect to the axial direction. |
