Patent ID: 8881512

Claim:
A catalyst converter device for purifying exhaust gas with a catalyst retainer having a catalyst carried by a ceramics honeycomb carrier of a cylindrical shape and retained by a metal tubular member covering the outer part of the catalyst retainer through a retaining mat, comprising: a thickness of the retaining mat is set wherein the apparent density of the retaining mat during assembling becomes 0.25 g/cm 3 or more and less than 0.51 g/cm 3 and the outside diameter (D 1 ) of the catalyst retainer is set according to an interference of the retaining mat when the retaining mat wound around the catalyst retainer passes through a press-in tool that presses-in the catalyst retainer to the metal tubular member and an interference of the retaining mat after being pressed into the metal tubular member within a range that does not exceed a predetermined single body allowable strength of the catalyst retainer; said retaining mat being formed of a non-expandable inorganic fiber sheet; a catalyst retainer pressing force for moving the catalyst retainer in an axial direction with respect to the metal tubular member that is obtained from a pressure difference of exhaust gas applied to the upstream side and downstream side of the catalyst retainer when the catalyst converter device for purifying exhaust gas is used inside an exhaust pipe or inside a muffler with an external force generated by vibration applied to the catalyst retainer; and the length (L 2 ) along the longitudinal direction of the catalyst retainer in the retaining mat wound around the catalyst retainer is set longer than the winding diameter of the retaining mat around the catalyst retainer wherein a retaining force (R) larger relative to the catalyst retainer pressing force (F) can be secured: F=G·M+P·S wherein: G: acceleration of vibration of the catalyst retainer during use M: mass of the catalyst retainer P: difference of the pressure of the exhaust gas applied to the upstream side and downstream side of the catalyst retainer during use S: pressure receiving area of the catalyst retainer.