FUEL INJECTION DEVICE IN INTERNAL-COMBUSTION ENGINE

PURPOSE:To obtain an optimum injection rate in accordance with the operating condition of an engine, by disposing a one-way valve, an accumulating device and a variable orifice device, in the mentioned order from the upstream side, in fuel pressure-feed passage between the fuel injection part of a fuel injection device and an injection nozzle. CONSTITUTION:When high pressure fuel fed from a distributing type fuel injection pump 5 through a fuel pressure-feed passage 6 increases its pressure above a pressure P1 corresponding to a set load of a spring 2 in an injection nozzle 1, a needle valve 4 is lifted to allow fuel to be injected from a jet port 3. Further, a variable orifice device 9 which is disposed in a fuel nozzle body 1a, is controlled by a control device 8 to restrict the passage area of a fuel pressure-feed passsage section 6c to a small degree in a high load operating range, but to a large degree in a low speed operating range. Further, the fuel pressure-feed passage 6 is disposed therein with a delivery valve 15, an accumulating device 16 and a one-way valve 17 in the mentioned order from the downsteam side. With this arrangement, the amount of fuel injection may be appropriately changed in accordance with the operating condition of the engine.