Abstract: A uniflow scavenging two-cycle engine includes a scavenge port and a plurality of injection units which inject a fuel gas into the active gas sucked into the scavenge port and have different positions of the piston in the stroke direction. The plurality of injection units are divided into at least two sets of injection unit groups include first and second injection unit groups, the first injection unit group being a set of one or a plurality of injection units located on the other end side in the stroke direction, and the second injection unit group being a set of one or a plurality of injection units located on one end side in the stroke direction, and the injection stop of the fuel gas is later in the injection unit of the first injection unit group than in the injection unit of the second injection unit group.

Abstract: A uniflow scavenging 2-cycle engine includes a cylinder inside in which a combustion chamber is formed; a piston which slides within the cylinder; a scavenge port which is provided on one end side in a stroke direction of the piston in the cylinder to suck an active gas into the combustion chamber in accordance with the sliding movement of the piston; and an injection unit which injects a fuel gas into the active gas suctioned to the scavenge port and is provided on an inner circumferential surface of the scavenge port or on the outside of the cylinder rather than the inner circumferential surface. Further, the amount of the fuel gas injected by the injection unit on the other end side in the stroke direction is larger than the amount of fuel gas injected by the injection unit on one end side in the stroke direction.