| 摘要 |
PURPOSE:To enable injection amount and injection time to be controlled individually at will by controlling opening and closing time of a metering valve in a fuel injection valve. CONSTITUTION:Fuel is supplied through an introducing port 57 and a check valve 58 to a pressure chamber 36 while being sent through an oil guide path 62 to a fuel path 47 after it is sent from an oil reservoir 54a through an orifice path 60 of a metering valve 59 to a metering needle 61 to be subjected to flow control. The start of injection is determined by the valve closing time of the metering needle 61 and the injection is ended when an escape groove 51 and the upper end 55 of a free piston 42 coincide with escape holes 53, 56 for high pressure fuel. The more ascent amount of the free piston 42 is, i.e. the larger effective injection stroke of the piston 42 is, the more this coincidence time is delayed. Also the ascent amount of the free piston 42 varies in response to the valve opening time of the metering needle 61 so that injection time and injection amount can be varied by controlling the needle valve 61. |
