EXHAUST GAS PURIFICATION DEVICE FOR AN INTERNAL COMBUSTION ENGINE

摘要

To homogeneously diffuse, in the exhaust gas, an additive that is fed into a device for purifying exhaust gas of an internal combustion engine. An upstream device for purifying exhaust gas and a downstream device for purifying exhaust gas are connected together through an exhaust pipe having a sectional area smaller than that of the upstream device for purifying exhaust gas and that of the downstream device for purifying exhaust gas, a connection passage portion is provided to connect the exhaust outlet of a catalyst in the upstream device for purifying exhaust gas to the exhaust pipe, the connection passage portion being so formed that the center axis of the upstream device for purifying exhaust gas in the direction in which the exhaust gas flows is not aligned with the center axis of the exhaust pipe in the direction in which the exhaust gas flows, injection means is arranged in the connection passage portion to inject the additive into the exhaust passage so that the additive arrives at the opposing wall surface of the connection passage portion.