Accumulator fuel injector for diesel engine

Abstract

The present invention relates to an accumulator fuel injector for a diesel engine, the device including first and second accumulators which are connected through a check valve and a relief valve. Fuel pressurized and delivered by a fuel injection pump is charged into the first accumulator so as to increase its pressure abruptly. When the fuel pressure in the first accumulator reaches a selected relief pressure, the fuel is charged into the second accumulator through the check valve and is accumulated therein. When fuel injection is started by opening of an injection valve, the fuel accumulated in the first accumulator is injected through the injection valve and at the same time the fuel accumulated in the second accumulator flows out to the first accumulator through the relief valve so as to also be injected through the injection valve. When the injection pressure decreases to the relief pressure at the end of the injection, the relief valve closes so that the fuel in the second accumulator is prevented from flowing into the first accumulator, and only the fuel accumulated in the first accumulator is injected.