| 摘要 |
A fuel injection system for self-ignition internal combustion engines. At least part of the connecting line leading from the injection pump to the injection valve includes two circuits of different lengths which are connected in parallel in order to obtain a pre-injection phase and a main injection phase. In order to accurately set the fuel quantity for pre-injection, and the time interval relative to main injection or, respectively, the timing of the two fuel injections, and to make them independent of the level and the time characteristic of the pump pressure, i.e., ultimately independent of the speed and load of the engine, a special metering valve unit is provided in the shorter circuit of the divided connecting circuit, and a check valve unit is provided in the longer circuit at the end of the latter. Furthermore, the ratio of the diameter of the fuel line leading to the injection device, including the shorter circuit, to the diameter of the longer circuit (time-delay circuit) is between 1 and 2. |
