| 摘要 |
PURPOSE:To permit to avoid adhesion of atomized fuel to the inner wall of a suction port by a method wherein the taper angle of second taper part of a needle valve for a pintle type injection valve is equalized substantially to the angle of an umbrella-shaped par of a suction valve head with respect to the tip end of the injection valve. CONSTITUTION:In the needle valve 14 of the pintle type injection valve 1, the taper angle theta1 of the first taper part 19 and the conical angle theta3 of a conical end 21 affect the angle of mist not so much but relate exclusively to the atomization of fuel while the taper angle theta2 of the second taper part 20 has a close relation with the angle theta of mist and 0=theta2+ or -5 deg. is verified by an experiment. The taper angle theta2 is equalized substantially to the angle beta between the umbrella-shaped part 4 of the suction valve 3 and the tip end of the injection valve 1. According to this method, the adhesion of the mist of fuel to the inner wall of the suction port may be avoided, the response property of control may be improved and the supplying amount of fuel upon acceleration may be minimized. |
