摘要 |
An in-cylinder injection type spark-ignition internal combustion engine includes a spark plug (6), a fuel injection valve (7), and a piston (5) having a top face and a cavity (8) formed in a first part of the top face. The cavity is located closer to the fuel injection valve with respect to a center of the piston so as to bring the injected fuel toward the spark plug. A space formed in the cylinder at a top dead center of a compression stroke of the piston includes a first space in which a center of the cavity is located, and a second space. The first space is located on one side of a plane that passes through a center axis of the spark plug in parallel with a center axis of the cylinder and is perpendicular to a radial direction in which the center of the cavity deviates from the center of the piston. The second space is located on the other side of the plane. The top face of the piston is designed so as to reduce a volumetric difference between the first space and the second space, thereby preventing generation of a strong air stream flowing between the first space and the second space at around the top dead center. <IMAGE> |