Catalytic Converter Apparatus

Abstract

A catalytic converter apparatus includes a catalyst substrate that supports a catalyst for cleaning exhaust gas exhausted from an internal combustion engine, the catalyst substrate being heated by electrification; a case formed in a tubular shape, the catalyst substrate being accommodated inside the case and the case being attached to an exhaust pipe; an outer pipe provided at the case, the outer pipe being disposed at least at an upstream side of an exhaust gas flow direction relative to the catalyst substrate; an inner pipe provided at the case inside the outer pipe, an axial direction end portion of the inner pipe being formed in a tapered shape and a distal end face of the axial direction end portion being formed in a curved surface shape; and an insulating layer provided at least at an inner side face and the axial direction end portion of the inner pipe.

What is claimed is: 
     
         1 . A catalytic converter apparatus comprising:
 a catalyst substrate that supports a catalyst for cleaning exhaust gas exhausted from an internal combustion engine, the catalyst substrate being heated by electrification;   a case formed in a tubular shape, the catalyst substrate being accommodated inside the case and the case being attached to an exhaust pipe;   an outer pipe provided at the case, the outer pipe being disposed at least at an upstream side of an exhaust gas flow direction relative to the catalyst substrate;   an inner pipe provided at the case inside the outer pipe, an axial direction end portion of the inner pipe being formed in a tapered shape and a distal end face of the axial direction end portion being formed in a curved surface shape; and   an insulating layer provided at least at an inner side face and the axial direction end portion of the inner pipe.   
     
     
         2 . The catalytic converter apparatus according to  claim 1 , wherein, if a radius of curvature of the distal end face of the axial direction end portion is represented by R, chamfer machining is applied such that R≧0.5 mm. 
     
     
         3 . The catalytic converter apparatus according to  claim 1 , wherein a thickness of the insulating layer is set to at least 100 μm and at most 200 μm. 
     
     
         4 . The catalytic converter apparatus according to  claim 1 , wherein the axial direction end portion is an upstream end portion that is arranged toward the upstream side of the exhaust gas flow direction.