Combustion chamber arrangements in internal-combustion engines.

摘要

An internal combustion engine of the spark-ignited piston type has a piston crown of "pent-roof" shape and a cylinder head combustion chamber of corresponding shape. Formed on one inclined face [22] of the combustion chamber [20] is a recess [30] of generally ovate profile, having a plane roof [32] parallel to the face [22] and having a side wall [31] perpendicular thereto. The exhaust valve port [29] opens through one end of the roof of the recess [30] and the spark plug [37] protrudes through the other end. During the compression stroke as the piston [12] approaches top-dead-centre, gas is displaced by the "squish" effect from between the approaching inclined faces [16] and (21] of the piston crown and combustion chamber roof on one side of the apex [18,] [23] and travels across the combustion chamber and into the recess [30] in the other side of the roof thus producing gas movement and turbulence in the recess [30] where ignition takes place.