Abstract: The present invention relates to a catalytic converter apparatus for purifying exhaust gas from an internal combustion engine for vehicles. The catalytic converter apparatus includes a first catalytic converter that holds a first catalyst and that is to be coupled to a side of the engine, and a second catalytic converter that holds a second catalyst and that is coupled to a rear of the first catalytic converter. Each of the first and second catalysts has a catalytic support on which a wash coat layer having a thickness equal to or less than 0.2 mm is formed. The wash coat layer includes a first wash coat layer and a second wash coat layer, and each of the first and second wash coat layers has voids therein. This catalytic converter apparatus achieves an improved purification property with a small number of cells and a small amount of noble metal.

Abstract: The present invention relates to an exhaust gas purification apparatus which has an enhanced property of purifying exhaust gas from an internal combustion engine for vehicles, and which is configured to decrease the exhaust gas pressure of the engine. The exhaust gas purification apparatus includes an engine head block, where exhaust pipes combine, has a side on which an exhaust outlet is formed, a first catalytic converter that holds a first catalyst and that is to be coupled to a side of the engine head block, a second catalytic converter that holds a second catalyst and that is coupled to a rear of the first catalytic converter, an exhaust pipe that couples the engine head block to the first catalytic converter. Moreover, the first and second catalysts withstand a temperature equal to/more than 800° C.

Abstract: The present invention relates to a catalytic converter apparatus for purifying exhaust gas from an internal combustion engine for vehicles. The catalytic converter apparatus includes a first catalytic converter that holds a first catalyst and that is to be coupled to a side of the engine, and a second catalytic converter that holds a second catalyst and that is coupled to a rear of the first catalytic converter. Each of the first and second catalysts has a catalytic support on which a wash coat layer having a thickness equal to or less than 0.2 mm is formed. The wash coat layer includes a first wash coat layer and a second wash coat layer, and each of the first and second wash coat layers has voids therein. This catalytic converter apparatus achieves an improved purification property with a small number of cells and a small amount of noble metal.

Abstract: An exhaust emission control system for an internal combustion engine is provided. The exhaust emission control system (4) includes a monolith catalyst (MC) that includes an oxygen storage agent and a noble metal-based three-way catalyst including Pd, Rh, and Pt disposed at an upstream location in the exhaust gas flow in the internal combustion engine (2), and a perovskite-type double oxide having a three-way catalytic function disposed at a downstream location in the exhaust gas flow. The amount C1 of Pd carried is 0.97 g/L?C1?1.68 g/L, the amount C2 of Rh carried is 0.11 g/L?C2?0.2 g/L, the amount C3 of Pt carried is 0.06 g/L?C3?0.11 g/L, the amount C4 of the oxygen storage agent carried is 25 g/L?C4?75 g/L, and the amount C5 of the perovskite-type double oxide carried is 5 g/L?C5?15 g/L.

Abstract: The invention provides a catalyst deterioration detecting system that is capable of detecting the degree of deterioration of each catalyst in a catalyst converter which includes two or more catalysts in series. The catalyst deterioration detecting system of an internal-combustion engine according to the invention is provided with a upstream catalyst located on an upstream side of an exhaust system of the internal-combustion engine and a downstream catalyst located on a downstream side of the exhaust system. The device comprises an oxygen density detector which is disposed downstream of the downstream catalyst and a deterioration detector for detecting a deterioration degree of the upstream catalyst based on the output of the oxygen density detector. According to an aspect of the invention, the deterioration detector detects deterioration degree of the downstream catalyst based on the previously detected deterioration degree of the upstream catalyst.

Abstract: An exhaust emission control system for an internal combustion engine is provided. The exhaust emission control system (4) includes a monolith catalyst (MC) that includes an oxygen storage agent and a noble metal-based three-way catalyst including Pd, Rh, and Pt disposed at an upstream location in the exhaust gas flow in the internal combustion engine (2), and a perovskite-type double oxide having a three-way catalytic function disposed at a downstream location in the exhaust gas flow. The amount C1 of Pd carried is 0.97 g/L≦C1≦1.68 g/L, the amount C2 of Rh carried is 0.11 g/L≦C2≦0.2 g/L, the amount C3 of Pt carried is 0.06 g/L≦C3≦0.11 g/L, the amount C4 of the oxygen storage agent carried is 25 g/L≦C4≦75 g/L, and the amount C5 of the perovskite-type double oxide carried is 5 g/L≦C5≦15 g/L.

Abstract: An exhaust gas purification device for a lean-burn engine that can be produced at a low cost. The exhaust gas purification device includes a three-way catalyst that, during stoichiometric operation of the engine, removes a lower proportion of CO than the proportion of HC removed. The three-way catalyst is positioned in the device on the upstream side of an exhaust pipe of the lean-burn engine, and a lean NOx catalyst is positioned in the device on the downstream side of the exhaust pipe. A perovskite type double oxide is used as the three-way catalyst instead of a precious metal.

Abstract: The invention provides a catalyst deterioration detecting system that is capable of detecting the degree of deterioration of each catalyst in a catalyst converter which includes two or more catalysts in series.

Abstract: A catalyst deterioration-determining system for an internal combustion engine has a catalyst arranged in the exhaust system, for purifying exhaust gases emitted from the engine, an oxygen concentration sensor arranged in the exhaust system at a location downstream of the catalyst, for detecting the concentration of oxygen present in the exhaust gases, and an ECU which controls the air-fuel ratio of an air-fuel mixture supplied to the engine in a feedback manner in response to the output from the oxygen concentration sensor. Determination of deterioration of the catalyst is carried out based on the output from the oxygen concentration sensor during execution of air-fuel ratio feedback control.

Abstract: An evaporative fuel-processing system for an internal combustion engine has an evaporative emission control system. An ECU carries out negative pressurization of the interior of the evaporative emission control system, by opening a purge control valve and closing a vent shut valve, and determines presence/absence of leakage from the evaporative emission control system, based on a rate of decrease in negative pressure within the system, by closing a purge control valve. Before the negative pressurization, the interior of the evaporative emission control system is opened to the atmosphere, and during the open-to-atmosphere, a pressure state within the fuel tank is estimated based on a rate of change in an output from a pressure sensor which senses pressure within the evaporative emission control system. The ECU determines whether the evaporative emission control system is normal, based on the estimated pressure state.

Abstract: An evaporative fuel-processing system for an internal combustion engine has an evaporative emission control system and a pressure sensor. An ECU carries out negative pressurization of the interior of the evaporative emission control system, by opening a purge control valve and closing a vent shut valve. The purge control valve is closed over a predetermined time period after the interior of the evaporative emission control system is brought into the predetermined negatively pressurized state, and a rate of decrease in negative pressure within the evaporative emission control system is detected. Then, it is determined whether or not there is leakage from the evaporative emission control system, based on the detected rate of decrease in the negative pressure, and at least one detected pressure value at at least one predetermined time point within the predetermined time period over which the purge control valve is closed.