| 摘要 |
PROBLEM TO BE SOLVED: To increase area in which catalyst activation temp. is attained and to enhance exhaust gas purifying performance by arranging plural sheets of foil of a brazing filler metal between corrugated foil and flat foil, winding them around a central electrode and making the density of distributed heating points in the resultant electric heating catalyst carrier higher in the outer peripheral part than in the inner peripheral part. SOLUTION: An electric heating type catalytic device is provided with a cylindrical metallic foil laminated body as a catalyst carrier. This laminated body has a structure obtd. by spirally arranging through paths in the axial direction formed in the gaps between corrugated foil 3 and flat foil 4 around a central electrode 5 and an exhaust gas purification catalyst has been carried on the surfaces of the foil 3 and the foil 4. The joined parts of the laminated body are formed by sheets 8a, 8b of foil of a brazing filler metal between the foil 3 and the foil 4 and the overlaps of the joined parts are allowed to act as heating points hp (hp1 to hp3). Since the density of the distributed heating points hp is higher in the outer peripheral part than in the inner peripheral part, heat transferred to the air through the outer tube is compensated, the catalyst activation region is expanded and the rate of purification of exhaust gas is increased. |
