Loop scavenged two-stroke internal combustion engine

摘要

A loop scavenged two-stroke internal combustion engine which can effectively restrain blow-by of fresh gas with a relatively simple configuration is provided. A horizontal scavenging angle ¸b in at least one spot of a scavenging passage 31L located at one side of the pair of or a plurality of pairs of left and right scavenging passages is made to differ from a horizontal scavenging angle ¸a of a scavenging passage 31R located at the other side, and a main flow of a scavenging flow which is blown out from the scavenging passage 31L located at the one side and a main flow of a scavenging flow which is blown out from the scavenging passage 31R which is located at the other side intersect each other or collide with each other in plane view in a region displaced in a lateral direction from a center line C of an opening of an exhaust port 34.