Fuel Injection: How do Fuel Injectors Work

Development and History of Fuel Injectors

Prior to 1980's all internal combustion engines, irrespective of their application, did not have fuel injectors. Instead, a device that was known as a carburetor, was installed to evenly and proportionately mix air and fuel (diesel or gasoline). Though carburetor was the basis of the earlier combustion engine, it had some drawbacks. It was not exactly reliable as it would malfunction, in case of sudden atmospheric changes and temperature rise. One of the most unreliable part of the carburetor, is that it stops working if the engine temperature turns too high. The carburetor also requires a manual adjustment, that cannot be made by all people. Hence, as an alternative to overcome the demerits of carburetors, fuel injectors were developed by automobile manufacturers. Now-a-days very few automobiles are attached with carburetors.

How do Fuel Injectors Work

The carburetor have a very simple functioning procedure. The carburetor simply mixes the fuel and air, and inserts the mixture in the piston block. However the fuel injectors have a more complex functioning. The fuel injector system relies on a high pressure piping network in the engine. Here's how it is constructed and actually works.

After the fuel leaves the fuel tank, a filter is used to purify it from all unwanted contents and residue that runs from the fuel tank. An individual injector is actually an electromagnetic device that is shaped roughly like a syringe. There is a magnet attached at the top of the injector and a small valve is present at the bottom. Due to the pressure of the fuel, that comes through the filter, the valve is forcefully closed. The piston lies beyond this valve. The magnet is in a suspended state, which is done with the help of a spring. An electrical coil surrounds the magnet and a distance of about half an inch is maintained from the magnet. When the injector has to come into action, an electrical timing system, that is fitted on to the engine, alerts the coil with an mechanical charge. The magnet due to the electrical charge gets attracted towards the coil and moves in an upward direction. Due to this the valve at the bottom of the injector is lifted upwards, and fuel is sprayed with an immense pressure into the piston block. The pressure, heat and the electrical spark from the spark plug cause the whole fuel to ignite and explode, propelling the automobile forward. As a result of the propulsion, the electric charge is canceled and the injector comes back to its normal state, ready for a new firing.

Advantages of Fuel Injectors

The development of fuel injectors have revolutionized, the process of firing in internal combustion engines. The biggest advantage of a fuel injector is that the flow of fuel in the engine is properly regulated. A regulated flow prevents the wastage of fuel and also results into concentrated utilization. The second biggest advantage is that, emission of harmful compounds like carbon monoxide, is reduced drastically. Some highly reputed manufacturers of automobiles, have also managed to omit this emission. The injectors are also highly reliable and work efficiently in any natural conditions.

The fuel injectors have indeed revolutionized the internal combustion engine. They are also rapidly turning to be an universally used component.