Internal combustion engine

Claim 1

A diesel engine, comprising: at least one cylinder; a cylinder head at the top of said cylinder, said cylinder head having air inlet means for letting air into said cylinder; an injection nozzle for injecting fuel jets into the top of said cylinder; and a piston having a combustion chamber for receiving said fuel jets when said piston is adjacent said cylinder head, said combustion chamber having a frustoconical side surface extending from a relatively narrow open throat at the top of said chamber to a transition region adjacent a relatively wide bottom surface of the chamber, said throat having a peripheral edge, said frustoconical side surface tapering in the direction of the throat at an angle of 30°-60° to the cylinder axis, the diameter of said throat being equal to 0.32-0.37 times the cylinder inside diameter, the transition region from said frustoconical side surface of said bottom surface of the combustion chamber being smooth along a radius thereof, the diameter D 1 of the combustion chamber at a distance b from said throat edge equal to half the height h of the combustion chamber between the closest plane of said throat edge and said bottom surface being less than the maximum diameter D 2 of the transition region, said injection nozzle being mounted in an inclined position in the cylinder head relative to the cylinder axis, said injection nozzle being positioned relatively close to the throat edge and relatively remote from the center of said throat, at a position permitting penetration of fuel jets from said nozzle into said combustion chamber through the throat thereof, said injection nozzle having at least four fuel jet channels for directing fuel jets onto the side surface of the combustion chamber, so that mixing is effected when the fuel jets are acted upon by radial vortex streams of an air charge appearing in the combustion chamber during the motion of the piston at the end of the compression cycle and at the beginning of the expansion cycle, the extended axes of said fuel jet channels intersecting the side surface of the combustion chamber above the portion thereof having the diameter D 1 , said extended channel axes forming different angles with each other and dividing each horizontal section of said side surface into a plurality of parts, the angle between the projections of the extended channel axes of a first pair of adjacent channels for supply of fuel onto the closest part of the combustion chamber side surface to said nozzle being 1.8 to 2.2 times the angle between the projections of the extended channel axes of any other pair of adjacent channels for supply of fuel onto the portion of the combustion chamber side surface which is most remote from said nozzle, said channel axes being inclined at an angle β from the longitudinal axis of said nozzle and intersecting at a point lying substantially in the plane of the upper edge of said throat when the piston is in the top dead center position thereof, said channel axes being generatrices of a conical surface with a vertex angle 2β, said injection nozzle being inclined from a vertical axis parallel to the cylinder axis by an angle φ, said frustoconical side surface intersecting the side surface of the combustion chamber (i) on the side of the throat closest to the nozzle at a depth of 3/4b from the throat edge, and (ii) on the side of the edge of said throat most remote from the nozzle at a depth of 1/2b, where b is equal to half the height of the combustion chamber between the plane of said upper throat edge and said bottom surface.