| 摘要 |
The present invention has an object to prevent a short-circuit between a heat generation element, which is electrically energized to generate heat, and a case in an electrically heated type exhaust gas purification apparatus. In order to achieve this object, the present invention is constructed such that a laminated body composed of a holding member and an inner cylinder is arranged between a heat generation element, which is electrically energized to generate heat, and a case which covers the heat generation element, and the inner cylinder has an upstream side end portion extended to a more upstream side than an upstream side end face of said heat generation element and an upstream side end face of said holding member to form an extension portion, which is formed with a protruding portion protruding to an inner side in a diametrical direction. A flow of an exhaust gas, which flows backwards after colliding with the heat generation element, will be obstructed by said protruding portion. As a result, the backflow exhaust gas stops flowing into a gap between the case and the inner cylinder. Therefore, a drop in insulation, resulting from an inner peripheral surface of the case, an upstream side end face of the holding member, and an outer peripheral surface of the inner cylinder being covered with particulate matter, is suppressed. |
