Patent attributes
A cylinder head includes an intake throat and an intake duct, a valve seat ring is provided in an inner ring of the intake throat; a section of the intake duct is a tumble generating duct; and an extending direction of the tumble generating duct is oblique relative to the cylinder head bottom surface, the lower side surface of the tumble generating duct is a tumble guide surface, the lower end of which forms a tumble generating sharp angle, and the projection of the tumble generating sharp angle on the upper end circular surface of the valve seat ring is a sharp angle projection, the sharp angle projection is a protruding area protruding from the edge of the upper end circular surface of the valve seat ring, and the width of the middle part of the sharp angle projection is larger than the width of both ends thereof.