How the injector works

Release time:

Oct 04,2021

The injector is installed on the cylinder head near the intake manifold or air inlet through a sealing ring, and the electromagnetic coil is turned on according to the fuel injection pulse signal sent by the ECU.Under the action of the magnetic field of the electromagnetic coil, the needle valve overcomes the spring force and rises to spray fuel into the intake manifold or main pipeline.When the electronic control unit turns off the injector, the injection stops.When the structure of the injector and the injection pressure are constant, the injection volume of the injector depends on the opening time of the needle valve, that is, the power-on time of the solenoid.The fuel comes from the high-pressure oil circuit, flows through the channel to the injector, and at the same time flows to the control room through the throttle hole. The throttle hole is connected to the oil circuit through the drain hole, and the switch of the drain hole is controlled by a solenoid valve.When the discharge hole is closed, the hydraulic pressure acting on the needle valve control piston exceeds the force acting on the pressure surface of the injector needle valve.As a result, the needle valve was forced into the valve seat and the high-pressure channel was isolated and sealed from the combustion chamber.When the injector solenoid valve is triggered, the discharge hole opens, causing the pressure in the control room to drop.Therefore, the hydraulic pressure on the piston will also decrease.Once the hydraulic pressure drops below the force acting on the pressure surface of the needle valve of the fuel injector, the needle valve opens and the fuel is injected into the combustion chamber through the nozzle hole.The amount of fuel injection is determined by the width of the electrical pulse; pulse width = fuel injection duration = fuel injection amount.