ELECTRIC HEATING CATALYST

摘要

The present invention is intended to suppress a short circuit between a heat generation element and a case in an electric heating catalyst (EHC). The EHC 1 according to the present invention is provided with: a heat generation element (catalyst carrier) (3) adapted to be electrically energized to generate heat; a case (4) receiving the heat generation element (3) therein; an insulating support member (5) arranged between the heat generation element (3) and the case (4); an inner pipe (6) that is a tubular member which is inserted into the insulating support member (5) so as to be located between the heat generation element (3) and the case (4), wherein the inner pipe (6) has an end thereof protruding into an exhaust gas from an end face of the insulating support member (5), and the inner pipe (6) has an electrically insulating layer formed on an entire surface thereof, or the inner pipe (6) is formed of an electrically insulating material; and an inner pipe heater (10) that is supplied with electricity through a path which is different from a path through which electricity is supplied to the heat generation element (3), thereby to heat a protrusion portion (6a) of the inner pipe (6).