Patent ID: 6178942
Filing Date: 2001-01-30
Classification: F02B,Y02T

Abstract:
In a piston for a reciprocating piston internal combustion engine in which a combustion cycle is carried out in a variable volume combustion chamber defined by the piston reciprocating in a close ended cylinder into which a combustible mixture of fuel and air is periodically supplied, and which cycle includes intake, compression, combustion, expansion and exhaust portions, and wherein the piston crown includes a recess that contains the majority of the fuel and air mixture when the combustion chamber is at minimum volume and further wherein the fuel and air are caused to swirl in a swirl direction within the recess;said piston including at least one reaction chamber having a curvilinear cross-section extending circumferentially in the piston crown area adjacent the periphery of the recess, and an array of discrete orifices including at least one fuel control orifice and at least one air control orifice, said array of discrete orifices providing the sole communication between the recess and the reaction chamber,said at least one fuel control orifice being located so as to receive and control admission of primarily fuel of said mixture to the reaction chamber during each intake and compression portion of each combustion cycle and said at least one air control orifice being arranged to receive and control admission of primarily air of said mixture to the reaction chamber during each intake and compression portion of each combustion cycle, said respective fuel and air control orifices intersecting the reaction chamber at separate locations;said reaction chamber and orifices being shaped and dimensioned such that during the compression portion of each combustion cycle, a portion of the fuel and air mixture is admitted into the reaction chamber through the orifices in a manner such that the mixture admitted to the reaction chamber is at least partly vortically swirled in intimate contact with the sidewalls of the reaction chamber so as to effect heat transfer to the admitted mixture and its partial oxidation reaction to create radical species of the fuel and any flame front approaching the reaction chamber from the combustion chamber is quenched so that radicals of the fuel are produced and retained temporarily in the reaction chamber during the combustion, expansion and exhaust portions of the combustion cycle and are discharged into the piston recess following the conclusion of said exhaust portion in advance of the compression portion of the succeeding combustion cycle in sufficient quantity to condition the succeeding charge in the combustion chamber for preselected ignition and combustion characteristics; anda fuel directing system arranged to direct a portion of fuel of the mixture towards the fuel control orifice;the improvement comprising:said array of orifices being arranged so that, along the circumferential direction of the reaction chamber, flow of air and fuel into the chamber through the orifices creates non-symmetric chaotic circulatory flow patterns in the reaction chamber;said array of orifices comprising at least a first row of aligned orifices extending along the central cross-sectional area of the reaction chamber and at least a second row of aligned orifices extending diagonally along the reaction chamber length, said at least first and second orifice rows intersecting each other;at least the endmost orifices of said second row being located for tangential communication with the curvilinear cross-section of the reaction chamber.