Introduction
“Improvement in technology today will leads you a greater efficiency tomorrow” very rightly said as with the increase in dependency of human being on machines not only makes the life easy but also increases fuel demands, specifically if we talk about automobiles, the number of vehicles on road increasing tremendously since the start of the 20th century which directly reflects the fuel demands as well as prices , so it became the necessity for the researchers to innovate a system which can make the drive affordable as well as reliable. To solve this problem, in 1920 Bosch came up with a device name ‘Fuel Injector’ for diesel engine that was a boom in the field of combustion engines so let’s just dig in for more details.
What is Fuel Injector?
A fuel injector is an electronically controlled mechanical device which is used to inject/spray (just like a syringe) the fuel into the engine for the preparation of correct air-fuel mixture which in turn provides efficient combustion to the engine?
The position of the fuel injectors differs for different engine designs but usually they are mounted on the engine head with a tip inside the combustion chamber of the engine.
Why do we Need Them?
Fuel injectors are the necessity of all the automobile vehicles these days because-
- The working principle of internal combustion engines directly indicates that better the quality of fuel-air mixture better will be the combustion which in turn provides higher engine efficiency, so we need fuel injectors which provides far better air-fuel mixture quality than carburetors.
- The improper air-fuel mixing provided by carburetors leaves various un-burned particles inside the combustion chamber of an internal combustion engine which leads to improper propagation of combustion flame due to which engine malfunctioning known as knocking or detonation takes place, so to avoid this almost all the vehicles on road today adopted fuel injection technology.
- The wastage of fuel in the form of carbon or un-burned particles inside the combustion chamber directly reflects the mileage of the vehicle, which is not desirable, so to avoid this, adopting fuel injection technology becomes essential.
- In case of carburetors, controlling the air-fuel mixture quality and timing(fuel metering) is not precised as in carburetors, the adjustments can be done mechanically, but when it comes to fuel injectors due to its smart electronically controlled unit or e.c.u high precision of fuel metering can be achieved.
- It has been seen that not only the mileage but also the performance of the fuel injected vehicles is better than that of carbureted vehicles.
Types of Fuel Injectors
The advancement in fuel injection technologies gave rise to various fuel injection arrangements like throttle body fuel injection, multi-point fuel injection, sequential fuel injection and direct injection that can be used according to the application but when it comes to types of fuel injectors then it is really a tough call to categories them. According to us fuel injectors can be categorised as –
On the Basis of Fuel
On the basis of fuel injected injectors are of 2 types-
1. Diesel Fuel Injectors
These fuel injectors are used to inject or spray the diesel (which is heavier fuel than gasoline) directly into the combustion chamber of the diesel engine for further combustion by compression.
The capillary and nozzle of diesel fuel injectors are made in such a fashion that they can form the diesel packets while spraying the fuel inside the combustion chamber.
Diesel fuel injectors required higher injection pumping than gasoline injectors as diesel is heavier than gasoline.
2. Gasoline Fuel Injectors
They are the fuel injectors used to inject or spray gasoline directly or through intake manifold into the combustion chamber for further combustion by spark.
The capillary and nozzle of gasoline fuel injectors is made smaller or same as the diesel fuel injectors depending upon the requirement.
As the gasoline is lighter than diesel, gasoline injectors required less injection pumping than diesel injectors.
On the Basis of Fuel Metering
On the basis of fuel metering (controlling speed, quantity and pressure of the fuel) fuel injectors are of 2 types-
1. Mechanically Controlled Fuel Injectors
They are the fuel injectors in which the control of the fuel speed , quantity, timing and pressure is done mechanically with the help of spring and plunger which takes the input from the cam and fuel pump arrangement or by fuel distributor (advanced one).
2. Electronically Controlled Fuel Injectors
They are the fuel injectors in which the control of fuel speed, quantity, pressure and timing is done electronically with the help of electronic solenoid which takes the input either from fuel distributor or from electronic control unit (advanced one) of the vehicle.