The engine consists of two main mechanisms: a crank mechanism and a gas distribution mechanism, as well as five main systems, including cooling, lubrication, ignition, fuel supply and starting systems.
1. The function of crank mechanism is to provide a combustion site that converts expansion pressure of gas generated by combustion of fuel on top of piston into crankshaft rotation torque and continuously outputs power.
2. The valve mechanism regularly opens and closes intake and exhaust valves of each cylinder, so that fresh fuel mixture (gasoline engine) or air (diesel engine) can enter cylinder in time, and exhaust gas can be released from cylinder in time
3. The function of an automotive cooling system is to dissipate some of heat absorbed by hot parts in a timely manner to ensure that engine runs at most suitable temperature.
4. The function of lubrication system is to continuously supply a sufficient amount of clean engine oil of appropriate temperature to all parts of transmission while engine is running and formation of an oil film between them.
5.The car's ignition system is an ignition type engine. For normal operation, according to ignition sequence of each cylinder, high-voltage high-energy electricity (about 15000 -30000V) is regularly supplied to spark plug to ensure that spark plug produces a spark strong enough to ignite fuel. gas mixture.
6. According to requirements of different engine operating conditions, supply system prepares a certain amount and concentration of combustible mixed gas and supplies it to cylinder to be ignited and burned when compression is approached. end, and expand to do job. Finally, supply system must also remove combustion products - exhaust gases - into atmosphere.
7. The starting system ensures smooth formation, compression and ignition of mixture.
In a gasoline engine, ignition of combustible mixture in cylinder occurs from an electric spark, so a spark plug is installed on cylinder head of a gasoline engine, and spark plug head goes into combustion chamber. . All equipment capable of generating an electrical spark between electrodes of a spark plug in time is called an ignition system. The traditional ignition system consists of batteries, alternators, ignition coils, distributors, spark plugs, etc. The original and conventional ignition systems are similar except that distributor has been replaced with electronic components.
Electronic ignition type is a fully electronic ignition system that completely overrides mechanical device, and ignition timing is controlled by electronic system, including the battery, alternator, ignition coil, spark plug and electronic control system.