Reciprocating engine with cylindrical combustion chamber

摘要

A reciprocating internal combustion engine has a cylindrical combustion chamber lying substantially entirely within the cylinder head and including a fuel injection nozzle and possibly a glow plug. The top of the cylindrical combustion chamber is defined by the disc of the intake poppet valve and the bottom of the combustion chamber is defined at top dead center by a projection of the piston which is formed in a piston cap that consists of thermally resistant material and within which there is an air-filled void that prevents the heat transfer from the combustion chamber to the main body of the piston. This construction permits high surface temperatures within the combustion chamber without attendant heavy thermal stresses in the body of the piston.