Vehicle and single-cylinder four-stroke engine unit

• Main Authors: NISHIGAKI MASATO, WAKIMURA MAKOTO, ARAKI YUUJI, ISHIZAWA KAZUHIRO
• Format: Patent
• Language: Chinese; English
• Published: 01.03.2017
• Subjects: BLASTING; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; STEAM ENGINES; WEAPONS

The objective of the present invention is to provide a vehicle that is equipped with a single-cylinder four-stroke engine unit with which oxygen concentration in an exhaust gas can be more stably detected. According to the present invention, at least a portion of a main catalyst (39) for a single combustion chamber is positioned further to the front than a crank axis (Cr1), and in an exhaust channel from one combustion chamber (29) to an emission port (35e), the main catalyst (39) for a single combustion chamber purifies, to the greatest extent, the exhaust gas discharged from the one combustion chamber (29). An upstream oxygen detection member (37) for a single combustion chamber is disposed further upstream in the flow direction of the exhaust gas than the main catalyst (39) for a single combustion chamber. The channel length from the one combustion chamber (29) to the upstream oxygen detection member (37) for a single combustion chamber is longer than the channel length from the upstream oxygen detection m