0445120087 Diesel Fuel Injector Common Rail Injector Assembly for Weichai

the Structure and Principle of injector

The fuel injector is a precision device with very high machining accuracy, which requires a large dynamic flow range, strong anti-clogging and anti-pollution capabilities, and good atomization performance. The working principle of the fuel injector is to receive the fuel injection pulse signal sent by the ECU to precisely control the fuel injection quantity.
The injector, which is a solenoid valve, is controlled by the engine control unit. Gasoline under the pressure of the oil distribution pipe enters the fuel injector, under the force of the return spring, the needle valve is in a closed state, and the fuel injector cannot inject fuel; when the ECU controls the solenoid coil of the fuel injector to be energized, the magnetic field generated by the solenoid coil drives the armature , The needle valve moves up, the needle valve opens, and the fuel injector injects fuel. Generally, the lift of the injector needle valve is about 0.1mm.
The principle of the fuel injector control circuit is shown in Figure 1. The electromagnetic coil of the fuel injector leads to two wires, one wire is the power supply, which supplies 12V voltage after the ignition key is turned on, and the other wire is the ground circuit controlled by the electronic control unit. When the fuel injector needs to open the fuel injection, the electronic control unit ECU controls the grounding of this line through the triode, and the electric current flows through the electromagnetic coil, and the fuel injector opens the fuel injection. Each time the ECU controls the magnetic flux of the injector electromagnetic wire is called the fuel injection pulse width, which is in the range of 2~10ms.