| 摘要 |
PURPOSE:To prevent the blowing-off of combustion gas or intrusion into basic material, developing heat insulating effect, by joining the back surface of a heat insulating member made of formed ceramics onto the wall surface of a combustion chamber and forming a ceramics-coated layer onto the back surface of the heat insulating member made of foamed ceramics. CONSTITUTION:The heat insulating structure of a combustion chamber of the piston 2 of a Diesel engine is constituted so that a recess 4 is formed at the center of the upper surface 3 of the piston 2, and the fuel jetted inside said recess 4 is ignited. In this case, a heat insulating member 12 made of foamed ceramics is connected onto the upper surface 3 and the surface of the recess 4 which are exposed to combustion gas, and heat transmission to the piston 2 is suppressed. Said heat insulating member 12 is formed from the ceramics having continuous gas holes 17, and a ceramics-coated layer 15 is formed onto the surface 13 which is formed flat and closes the gas holes 17. The back surface of the heat insulating member 12 thus formed is jointed onto the upper surface 3 and the recess 4 of the piston 2 by adhesive 16. |
