Piston with turbulence inducing face configuration

Claim 1

In an internal combustion engine including at least one cylinder, for an expandable combustion chamber, a piston operably positioned for reciprocating motion in said cylinder and a fuel injector being actuatable to introduce a stream of fuel to said expandable combustion chamber, and valve means opening into said combustion chamber for introducing a stream of air therethrough in a manner to cause said air to swirl rapidly about said combustion chamber, means forming a cylindrical walled primary cavity in the face of said piston and defining an open chamber therein, to receive fuel and swirling air, recess means formed into said piston face and positioned to receive a gaseous flow from said primary cavity during the piston power stroke, and defining at least one circular groove about said primary cavity, said at least one circular groove including an outwardly sloping wall connected with said piston face, and a substantially vertically sloping wall forming the periphery of said groove, whereby to facilitate intermixing of air with injected fuel to provide an improved combustion process.