It is an object of the present invention to achieve the improvement of the combustion efficiency in the combustion chamber and the improvement of the fuel consumption rate by forming, in the inner circumferential surface of a sleeve into which a projection...

The internal combustion engine has an injector (40) to inject fuel directly into the combustion chamber (16) of the working cylinders (14). At least one inlet valve (20) is provided per cylinder and has valve stem sealing constructed in such a way that it ...

In an exhaust port structure in an internal combustion engine, a cylinder head has a cylinder head body and a cylindrical exhaust port liner. The exhaust port liner is partially supported at a plurality of points on the cylinder head body , and a heat-insu...