18 Jan What Are Electronic Unit Injectors and How Do They Work?
The demands for improved power, enhanced fuel economy, quieter operations, and cleaner emissions from our engines has led to the development of the electronic unit injector. An electronic unit injector is a unit injector that has electronic control. Its camshaft-driven delivery of pressurized fuel coupled with management of the internal operations’ timing by an engine control unit allows electronic unit injectors to achieve certain benefits over conventional unit injectors.
The electronic unit injector is mechanically pressurized using the electronic control of metering, timing, and governing functions. It consists of a range of basic elements, such as the spring-loaded plunger and barrel (to pressurize the fuel in the injector), the poppet valve (to regulate the pressure build-up), an electric solenoid (to actuate movement of the needle or poppet valve fuel inlet), return passageways (to get an efficient flow of fuel) and the nozzle valve (to enhance atomization).
In a unit injection system, the nozzle and injection pump are integrated into one module. Thus, fuel pressurization, atomization, fuel distribution, and injection timing are accomplished in just one component. An electronic unit injector system is installed directly into a cylinder head over every combustion chamber. An engine camshaft drives the injector typically through the rocker lever, resulting in an efficient mechanical and hydraulic fuel system that can minimize parasitic losses. Fuel droplet sizes are smaller for enhanced emissions, and this finer atomization enables EGR flow tolerance into combustion mixtures.
With electronic unit injectors, you can expect reduced emissions and fuel consumption as long as the injectors are incorporated in an engine with other compatible components that can together bring out these advantages. High quality electronic unit injectors are designed for high end, heavy duty application. They allow for accurate injector control and enhanced fuel economy, thereby bringing optimized vehicle performance.