Patent ID: 8677950

Claim:
An internal combustion engine, comprising: a cylinder wall; an intake piston disposed within the cylinder wall; an exhaust piston disposed within the cylinder wall; and a first fuel injector disposed in an opening that pierces the cylinder wall; a second fuel injector disposed in a second opening that pierces the cylinder wall, wherein: the pistons are adapted to reciprocate within the cylinder walls; the second fuel injector is in an opposed arrangement with respect to the first injector; when tops of the pistons are at their closest approach, a volume between the pistons forms a combustion chamber with first, second, third, and fourth regions: the first region being substantially a first cone proximate the first injector with a tip of the first cone closer to the first injector and a base of the first cone away from the first injector; the second region being substantially a hemisphere with a flat surface of the hemisphere of the second region substantially coincident with a base of the first cone; the third region being substantially a second cone proximate the second injector with a tip of the second cone closer to the second injector and a base of the second cone away from the second injector; and the fourth region being substantially a hemisphere with a flat surface of the hemisphere of the fourth region coincident with a base of the second cone of the third region; and a cross section of the pistons coincident with the base of the cone of the first region shows the tops of the two pistons on each side of the hemisphere of the second region sloped so that thin ribbons that exist between the two piston tops when the pistons are at their closest approach are substantially tangent to a periphery of the hemisphere of the second region and a cross section of the pistons coincident with the base of the cone of the third region shows the top of the two pistons on each side of the hemisphere of the fourth region sloped so that thin ribbons that exist between the two pistons tops when the pistons are at their closest approach are substantially tangent to periphery of the hemisphere of the fourth region.