The Location and Function of the Fuel Injector

The fuel injector, also known as the electric fuel nozzle, is located on the cylinder head at the top of the engine piston. Its core function is to finely atomize the fuel into tiny droplets according to the characteristics of the mixture formation in diesel engines and accurately inject them into the designated areas of the combustion chamber.

As a key component of the fuel injection system, the fuel injector is responsible for transforming a certain amount of fuel from a liquid state into a mist state and then mixing it with air. For gasoline engines with external cylinder injection, the fuel injector sprays gasoline into the intake pipe of the engine. After forming a mist and mixing with air, this mixture is then drawn into the cylinder to burn during the intake stroke of the engine. For gasoline engines with in-cylinder injection, the fuel injector directly sprays gasoline into the cylinder. After forming a mist and mixing with air, it is ignited by the spark plug, which then drives the piston to do work.

In terms of structure, fuel injectors can be divided into several types according to different designs, such as pintle type, ball valve type and disc valve type. In terms of electrical characteristics, fuel injectors can be classified into low-resistance type and high-resistance type according to different resistance values. The resistance value of the low-resistance type is approximately 2 - 3Ω, while that of the high-resistance type is between 13 - 17Ω. In addition, according to different driving methods, fuel injectors can be further divided into two types: voltage-driven and current-driven. Voltage-driven is suitable for high-resistance fuel injectors and low-resistance fuel injectors with additional resistors, while current-driven is more suitable for low-resistance fuel injectors.