| 摘要 |
PURPOSE:To reduce a rapid volumetric change so as to prevent the development of erosion of the piston top by forming cutouts in the piston top at locations that nearly correspond to the perimeter of intake and exhaust ports which is intersected by the atomized fuel jet of the injected fuel. CONSTITUTION:When an engine is being operated, a high combustion impact pressure as well as an intense thermal load are applied to the piston top 15 at locations which are hit by the atomized fuel stream of the injected fuel 6. Further, as the piston 5 moves upward, there is a rapid volumetric change between the piston top 15 and the underside of the cylinder head. In this embodiment, cutouts 20 are formed in the piston top 15 at locations that nearly correspond to those parts of the perimeter of intake and exhaust ports 8, 9 which are intersected by the atomized jet of the injected fuel 6 from a fuel injection nozzle 7 to cross over the projected lines 16, 17 of the perimeter of the intake and exhaust ports 8, 9. Therefore, a rapid volumetric change is reduced by the cutouts 20, thereby preventing high-frequency pressure changes. |
