求翻译：，当没有输入控制讯号时，阀门一直处于关闭状态；而常开阀则是当没有输入控制讯号时，阀门一直处于开启状态，由一个阀针上下运动来控制阀的开闭。当ECU下达喷油指令时，其电压讯号会使电流流经喷油嘴内的线圈，产生磁场来把阀针吸起，让阀门开启好使油料能自喷油孔喷出。喷射供油的最大优点就是令燃油供给的控制十分精确，让引擎在任何状态下都能有正确的空燃比，不仅让引擎保持运转顺畅，其废气也能合乎环保法规的规范。是什么意思？

When no input control signal, the valve has been turned off; normally open valve when the input control signals, the valve has been turned on by the needle up and down movement of a valve to control the valve opening and closing. Ecu injector instructions issued, the voltage signal causes the curren