Combustion chamber for diesel engine with direct injection has piston face cavity with notches in cavity rim aligned with injector orifices

摘要

The combustion chamber, formed in an engine cylinder (4) between a piston face (3) and cylinder head (5), has a cavity (2) in the piston face and a fuel injector (12) projecting from the cylinder head surface in line with the centre of the cavity. The cavity opening (6) is restricted by a rim (7) which has notches in it aligned with the injector orifices and the fuel jets issuing from them. Each of the notches is generally cylindrical in shape with an elliptical base, meeting the cavity side wall (8) at a tangent.