FLAME SWIRL MIXING DEVICE FOR PISTON HEAD IN DIESEL ENGINE OF SUBCOMBUSTION CHAMBER TYPE

摘要

PURPOSE:To improve mixing of a combustion flame with air so as to reduce a generation amount of NOx by forming a flame swirl mixing chamber recessed in a piston head by a turn-shaped groove, and a swirl flame infiltration- preventing peripheral wall surface on the inner side from this turn-shaped groove. CONSTITUTION:A flame introducing path 4 and a flame swirl mixing chamber 5 are provided to be recessed in a piston head 3 of a piston 2 in an engine 1. A combustion flame 8, jetted from a jet 7 in a subcombustion chamber 6, is introduced from the flame introducing path 4, swirled in the flame swirl mixing chamber 5 and mixed with air. In the above device, the flame swirl mixing chamber 5 is formed by a turn-shaped groove 9. The turn-shaped groove 9 is formed by providing a concentrical disk-shaped protrusive part 25 in the center of disk-shaped recessed parts 24 respectively provided in both point end sides of the flame introducing path 4. And, the peripheral wall surface of the protrusive part 25 is formed as a swirl flame infiltration-preventing peripheral wall surface 10 protrusively provided on the inner side from the turn-shaped groove 9.