| 摘要 |
PURPOSE:To enable satisfactory swirl motion in air flow to be produced and achieve an increase in the volumetric efficiency of the combustion chamber in a Diesel engine by an arrangement wherein the combustion chamber is formed with a helical air inlet port and a tangential air inlet port and the timings of an air inlet valve opening and closing the air inlet valves are predetermined properly. CONSTITUTION:A combustion chamber 1 of each cylinder of a Diesel engine is formed with a helical air inlet port 2 and a tangential air inlet port 3, the upstream sides of both of which being connected to a surge tank 4 that is connected to an air intake pipe. Air inlet valves 6 and 7 are mounted in the downstream ends of the air inlet ports 2 and 3, respectively. The air inlet valve 6 is set to open later than the air inlet valve 7, i.e., in the range of crank angle from top dead center to 50 deg. after it, and close earlier than the valve 7, i.e., in the range of crank angle from bottom dead center to 40 deg. after it. Further, located at a proper position in the air inlet port 3 is a throttle valve 8 whose degree of opening is controlled by a device 10 for controlling the degree of opening of the valve so that swirl flow with an optimum velocity may be produced. |
