Patent ID: 6189508
Filing Date: 2001-02-20
Classification: F02M

Abstract:
A method of injecting fuel in multicylinder engines, comprising:generating a fuel pre-pressure to be converted within acceleration pipes by opening controlled shutoff valves and recirculating fuel to a fuel pump inlet;conveying the fuel under pre-pressure via a fuel pump into a pre-pressure common rail common to several engine cylinders, wherein the pre-pressure is only a fraction of the required injection pressure;feeding the fuel, when the pre-pressure is exceeded, from the pre-pressure common rail via pressure-limiting valves into a return common rail common to several engine cylinders when the shutoff valve is open; andshutting off the shutoff valves, provoking a steep rise of fuel pressure due to a water hammer effect, so that a high-pressure wave produced when a shutoff valve closes supplies high pressure for fuel injection through an injection nozzle associated with the shutoff valve,wherein for every shutoff valve one acceleration pipe is used between the pre-pressure common rail and the return common rail, and wherein at least one injection nozzle is actuated in the respective acceleration pipe per shutoff valve.