STRADDLE RIDING-TYPE VEHICLE

• Main Authors: ITOU, YUTAKA, MOROZUMI, NAOHIRO
• Format: Patent
• Language: English; French; Japanese
• Published: 02.04.2009
• Subjects: BLASTING; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; STEAM ENGINES; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; THEIR RELEVANT APPARATUS; TRANSPORTING; WEAPONS

A straddle riding-type vehicle having an internal combustion engine where combustion is taken place at an air-fuel ratio less than a theoretical air-fuel ratio, wherein the purification ratio of NOx is improved. A straddle riding-type vehicle has an internal combustion engine performing combustion at an air-fuel ratio less than a theoretical air-fuel ratio, a first catalyst provided in an exhaust route for discharging combustion gas from the engine, a second catalyst provided at that portion of the exhaust route which is downstream of the first catalyst, and a secondary-air introduction device for introducing secondary air into that portion of the exhaust route which is between the first and second catalysts. The first and second catalysts each contain a precious metal component including at least one of Pt, Rh, Pd, and Au. The first catalyst further contains an ammonia decomposing catalyst. L'invention vise à proposer un véhicule de type à conduite à califourchon ayant un moteur à combustion interne dans lequel la combustion a lieu à un rapport air-carburant inférieur à un rapport air-carburant théorique, le rapport de purification de NOx étant amélioré. A cet effet, l'invention concerne un véhicule de type à conduite à califourchon qui a un moteur à combustion interne effectuant une combustion à un rapport air-carburant inférieur à un rapport air-carburant théorique, un premier catalyseur disposé dans un trajet d'échappement pour évacuer du gaz de combustion à partir du moteur, un second catalyseur disposé au niveau de la partie du trajet d'échappement qui se situe en aval du premier catalyseur, et un dispositif d'introduction d'air secondaire pour introduire de l'air secondaire dans la partie du trajet d'échappement qui se situe entre les premier et second catalyseurs. Les premier et second catalyseurs contiennent chacun un composant en métal précieux comprenant au moins l'un de Pt, Rh, Pd et Au. Le premier catalyseur contient en outre un catalyseur de décomposition d'ammoniac.