Abstract: A uniflow scavenging two-cycle engine includes an scavenging port having a swirling guide portion that guides scavenging gas into a cylinder in a direction inclined with respect to a radial direction of the cylinder, and a center guide portion that is provided to be closer to a crank side of the cylinder than the swirling guide portion and guides the scavenging gas further toward the center side of the cylinder than the swirling guide portion. At least a part of the center guide portion faces a piston when the piston is positioned at bottom dead center during the high compression ratio mode, and the center guide portion and the piston do not face each other or an area of facing the piston is smaller than that during the high compression ratio mode when the piston is positioned at bottom dead center during the low compression ratio mode.

Abstract: A uniflow-scavenging-type two-cycle engine includes: a cylinder; a piston that slides in the cylinder; an exhaust port that is provided at a first end of the cylinder; an exhaust valve that opens and closes the exhaust port; a scavenging port that is provided in an inner circumferential surface of a second end of the cylinder in the stroke direction of the piston and inhales an active gas into a combustion chamber in accordance with a sliding movement of the piston; a plurality of fuel injection valves that inject a fuel gas to the active gas, which has been drawn in from the scavenging port to the combustion chamber, to thereby generate a premixed gas; and a fuel injection control unit that varies injection directions of fuel gas injected from a part or all of the fuel injection valves.

Abstract: A uniflow scavenging 2-cycle engine includes a cylinder inside 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 a fuel injection unit which has an injection port located on the outside of the cylinder, and injects the fuel gas into the active gas sucked into the scavenge port.

Abstract: A uniflow scavenging two-cycle engine includes an scavenging port having a swirling guide portion that guides scavenging gas into a cylinder in a direction inclined with respect to a radial direction of the cylinder, and a center guide portion that is provided to be closer to a crank side of the cylinder than the swirling guide portion and guides the scavenging gas further toward the center side of the cylinder than the swirling guide portion. At least a part of the center guide portion faces a piston when the piston is positioned at bottom dead center during the high compression ratio mode, and the center guide portion and the piston do not face each other or an area of facing the piston is smaller than that during the high compression ratio mode when the piston is positioned at bottom dead center during the low compression ratio mode.

Abstract: A two-stroke uniflow engine is provided with: a cylinder; a piston; an exhaust valve that is opened and closed in order to discharge exhaust gas that is generated inside the cylinder; a scavenging port that takes active gas into the interior of the cylinder in accordance with a sliding movement of the piston; a fuel injection port that is provided in the internal circumferential surface of the cylinder; a fuel injection valve that injects fuel gas into the fuel injection port; and a fuel injection control unit that executes control of the injection of the fuel gas in the fuel injection valve, wherein the fuel injection control unit decides at least one of an injection pressure and an injection time of the fuel injection valve based on a change in pressure inside the cylinder that is caused by a reciprocating movement of the piston.

Abstract: A uniflow scavenging 2-cycle engine includes a cylinder inside 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 a fuel injection unit which has an injection port located on the outside of the cylinder, and injects the fuel gas into the active gas sucked into the scavenge port.

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.

Abstract: A uniflow scavenging 2-cycle engine includes a cylinder; a piston sliding in the cylinder; scavenging ports formed in an inner circumferential surface of one end of the cylinder in a piston stroke direction and suctioning an active gas into the combustion chamber according to the piston sliding motion; fuel injection valves inject a fuel gas into the active gas suctioned into the combustion chamber; and an exhaust port formed in the other end of the cylinder. An exhaust valve driving mechanism opens and closes exhaust valves such that a time required to displace an exhaust valve from a fully opened position to a fully closed position is longer than that required to displace the exhaust valve from the fully closed position to the fully opened position. With this constitution, an injection start timing of the fuel gas can be advanced while blow-by of the fuel gas is suppressed.

Abstract: A uniflow-scavenging-type two-cycle engine includes: a cylinder; a piston that slides in the cylinder; an exhaust port that is provided at a first end of the cylinder; an exhaust valve that opens and closes the exhaust port; a scavenging port that is provided in an inner circumferential surface of a second end of the cylinder in the stroke direction of the piston and inhales an active gas into a combustion chamber in accordance with a sliding movement of the piston; a plurality of fuel injection valves that inject a fuel gas to the active gas, which has been drawn in from the scavenging port to the combustion chamber, to thereby generate a premixed gas; and a fuel injection control unit that varies injection directions of fuel gas injected from a part or all of the fuel injection valves.

Abstract: A uniflow-scavenging-type two-cycle engine according to the present invention includes: a cylinder in which a combustion chamber is formed; a piston that slides in the cylinder; a scavenging port that is provided at one end of the cylinder in a stroke direction of the piston and draws in an active gas into the combustion chamber in accordance with a sliding movement of the piston; a fuel injection section that is provided in the scavenging port on an outer side of the cylinder than a center of a width of the scavenging port in a penetration direction and injects a fuel gas to the active gas drawn in into the scavenging port.

Abstract: A uniflow-scavenging-type two-cycle engine of the present invention includes: a cylinder; a piston that slides in the cylinder; an exhaust port that is provided at a first end of the cylinder; an exhaust valve that opens and closes the exhaust port; a scavenging port that is provided in an inner circumferential surface of a second end of the cylinder in the stroke direction of the piston and draws in an active gas into the combustion chamber in accordance with a sliding movement of the piston; and a plurality of fuel injection valves that inject a fuel gas to the active gas, which has been drawn in from the scavenging port to the combustion chamber, to thereby generate a premixed gas.

Abstract: A two-stroke uniflow engine is provided with: a cylinder; a piston; an exhaust valve that is opened and closed in order to discharge exhaust gas that is generated inside the cylinder; a scavenging port that takes active gas into the interior of the cylinder in accordance with a sliding movement of the piston; a fuel injection port that is provided in the internal circumferential surface of the cylinder; a fuel injection valve that injects fuel gas into the fuel injection port; and a fuel injection control unit that executes control of the injection of the fuel gas in the fuel injection valve, wherein the fuel injection control unit decides at least one of an injection pressure and an injection time of the fuel injection valve based on a change in pressure inside the cylinder that is caused by a reciprocating movement of the piston.

Abstract: Disclosed herein is a two-cycle engine that includes an exhaust port which is opened and closed at one end portion in a longitudinal direction of a cylinder; a scavenging port which is opened and closed at the other end portion in the longitudinal direction of the cylinder; and a fuel injection port which injects a fuel into the cylinder provided between the exhaust port and the scavenging port, wherein the fuel begins to be injected in a state in which at least any one of the exhaust port and the scavenging port is opened.

Abstract: Disclosed herein is a two-cycle engine that includes an exhaust port which is opened and closed at one end portion in a longitudinal direction of a cylinder; a scavenging port which is opened and closed at the other end portion in the longitudinal direction of the cylinder; and a fuel injection port which injects a fuel into the cylinder provided between the exhaust port and the scavenging port, wherein the fuel begins to be injected in a state in which at least any one of the exhaust port and the scavenging port is opened.