Combustion chamber arrangements for I.C. engines

Claim 1

An internal combustion engine of the spark-ignited gasoline fuel injection type having a cylinder block formed with one or more cylinders, a piston reciprocable in each cylinder, a cylinder head, a primary ignition chamber associated with each cylinder and formed in the cylinder head, a throat through which a substantial part of the air charge drawn into the cylinder on each suction stroke of the piston is forced during each subsequent compression stroke into the chamber, and of which one end opens into the cylinder opposite a shallow recess in the upper surface of the piston crown while the other end opens obliquely into the chamber so that the charge entering the chamber rotates about an axis through the central portion of the chamber, the bottom of the chamber being formed in a plug member inserted in the cylinder head, the total top dead centre clearance being such as to provide a compression ratio not exceeding 12.1:1, a spark ignition plug projecting into the upper part of the primary ignition chamber, a fuel injection nozzle opening into the primary ignition chamber at a point of its surface upstream of the ignition plug and downstream of the throat with respect to the direction of rotation of the charge in the chamber, means for injecting the whole of the gasoline fuel through the injection nozzle into the primary ignition chamber during the compression stroke, and means for producing a spark at the sparking plug to ignite the swirling mixture of the said gasoline and the air with the air driven into the primary chamber through the throat.