| 摘要 |
PURPOSE:To suppress a Diesel knock in an engine and reduce its noise to be silenced, by arranging a subnozzle to appear in a swirl direction in the internal wall of a combustion chamber further providing a main nozzle to appear in a central side of the combustion chamber from the subnozzle so as to prevent a delay of ignition and a rapid rise of combustion pressure. CONSTITUTION:When an engine is driven in idle operation, a combustion chamber 2, in which a needle valve 4 is urged in accordance with the supply fuel pressure and fuel is atomized by opening a subnozzle 14 colliding against an internal wall 13 and evaporated by high temperature compressed air, distributes the fuel as a preliminary mixture of excellent ignitionability in a film state to the periphery of a wall part. Accordingly, slow combustion is attained by successively propagating a flame. Further if the pressure of fuel is increased, the engine is driven in high load operation by opening a main nozzle 9, and the combustion chamber 2, in which fuel having a large particle size and strong penetrating force is injected in the direction of a swirl S more toward the center of the combustion chamber 2 than the fuel injected from the subnozzle 14 and smooth combustion is attained by propagating a flame of the preliminary mixture slowly toward the center and suppressing a rapid rise of combustion pressure, enables, a silence of the engine to be improved by preventing a Diesel knock or the like. |
