Abstract In a two-cycle internal combustion engine, a charging port is provided in the wall of a cylinder at the diametrically opposite position to an exhaust port; at least one main scavenging port at least one auxiliary scavenging port are provided on each side of a vertical plane which includes the straight line interconnecting the centers of said exhaust and charging ports and extends along the axis of the cylinder, in such a way that said auxiliary scavenging port is closer to said charging port than said main scavenging port; the directions of said main and auxiliary scavenging ports are so established that the mixture may be injected from said respective ports upwardly at an angle of about 15* to the transverse sectional plane of the cylinder and the jets of mixture may intersect each other in a predetermined region which is located on the diameter of the cylinder contained in said vertical plane and at a position more than the half of the distance between the center of the cylinder and said charging port distant from the center of the cylinder toward said charging port; the direction of said charging port is so established that the jet of mixture injected from said port may be directed toward a space slightly above said region of intersection of said scavenging flows and flow along the upper side of said scavenging flows without directly crossing them; and that reed valve means through which the mixture is sucked is disposed in that side of the crank case where the tangential component of rotational force of the crank shaft is directed toward the cylinder skirt and at a position adjacent said cylinder skirt, and the openings of said charging and auxiliary scavenging passage and, if necessary, the opening of said main scavenging passage are located circumferentially of said cylinder skirt and adjacent said reed valve means, whereby a kinetic energy is imparted to the mixture, sucked into the crank case, by making use of the tangential component of rotational force of the crank shaft and thereby the mixture is urged toward and directed into the openings of said respective passages and, therefore, the charging of the mixture into the cylinder is promoted, the scavenging and charging efficiency are enhanced and the engine output is increased.
A two-cycle internal combustion engine with crank case containing a crank shaft in a cylinder, comprising a reed valve means for introducing the combustible mixture therethrough disposed in that side of the crank case where the tangeNtial component of rotational force of the crank shaft is directed toward a skirt of the cylinder; a charging port provided in the wall of the cylinder in a diametrically opposite position to an exhaust port; at least one main scavenging port and at least one auxiliary scavenging port provided on each side of a vertical plane containing the straight line connecting the centers of said exhaust port and said charging port and extending along the axis of the cylinder, the relative position of said main scavenging port and said auxiliary scavenging port being such that said auxiliary scavenging port is closer to said charging port than said main scavenging port; the directions of said main and auxiliary scavenging ports so established that the mixture may be injected from said ports upwardly at an angle of approximately 15* to the transverse sectional plane of the cylinder and jets of mixture injected from all of said ports may intersect each other in a region located between the center of the cylinder and a generating line of the cylinder inclusive of said charging port on a diameter of the cylinder contained in said vertical plane; the direction of said charging port so established that the mixture injected from said port is directed upwardly at an angle of approximately 60* to the transverse sectional plane of the cylinder toward a space slightly above said region of intersection and provides a uni-flow not directly crossing the main and auxiliary scavenging flows; other open ends of passages communicating with said auxiliary scavenging port and said charging port being located in the cylinder mounting face of the crank case and at positions adjacent said reed valve means to utilize the tangential component of rotational force of the crank shaft to urge the mixture within the crank case toward and direct it into said auxiliary scavenging ports and said charging port to be injected into the cylinder.
Claim 2
Dependent Claim
356 words
A two-cycle internal combustion engine with crank case containing a crank shaft in a cylinder, comprising a reed valve means for introducing the combustible mixture therethrough disposed in that side of the crank case where the tangeNtial component of rotational force of the crank shaft is directed toward a skirt of the cylinder; a charging port provided in the wall of the cylinder in a diametrically opposite position to an exhaust port; at least one main scavenging port and at least one auxiliary scavenging port provided on each side of a vertical plane containing the straight line connecting the centers of said exhaust port and said charging port and extending along the axis of the cylinder, the relative position of said main scavenging port and said auxiliary scavenging port being such that said auxiliary scavenging port is closer to said charging port than said main scavenging port; the directions of said main and auxiliary scavenging ports so established that the mixture may be injected from said ports upwardly at an angle of approximately 15* to the transverse sectional plane of the cylinder and jets of mixture injected from all of said ports may intersect each other in a region located between the center of the cylinder and a generating line of the cylinder inclusive of said charging port on a diameter of the cylinder contained in said vertical plane; the direction of said charging port so established that the mixture injected from said port is directed upwardly at an angle of approximately 60* to the transverse sectional plane of the cylinder toward a space slightly above said region of intersection and provides a uni-flow not directly crossing the main and auxiliary scavenging flows; other open ends of passages communicating with said auxiliary scavenging port and said charging port being located in the cylinder mounting face of the crank case and at positions adjacent said reed valve means to utilize the tangential component of rotational force of the crank shaft to urge the mixture within the crank case toward and direct it into said auxiliary scavenging ports and said charging port to be injected into the cylinder.