The structure of the fuel injector
1.Type and structure of injector:
a. According to the structure of the fuel injection port, it can be divided into needle type and hole type.
b. According to the coil resistance: high resistance (13 ~ 16Ω) and low resistance (2 ~ 3Ω)
c, by use: MPI, SPI 6
d. According to the fuel position: top fuel supply type and side fuel supply type.
2. Fuel injection process:
a. The injector is equivalent to a solenoid valve.
b. When energized, the electromagnetic coil generates electromagnetic force, the armature and the needle valve are sucked up, the injector is opened, and the gasoline is injected into the intake port or intake pipe through the injection hole.
C. When the power is off, the electromagnetic force disappears, the armature and the needle valve close the nozzle hole under the action of the return spring, and the injector stops injecting fuel.
d. The power-on and power-off of the injector is controlled by the electronic control unit with electric pulses.
e. The amount of fuel injection is determined by the width of the electric pulse. Pulse width = injection duration = injection volume
f. Generally, the lift of the needle valve is about 0.1mm, and the fuel injection duration is in the range of 2 to 10 ms.
