What are the two major mechanisms and five major systems of an automobile engine?
2 Answers
The two major mechanisms of an automobile engine are the valve train mechanism and the crankshaft-connecting rod mechanism. The five major systems are the starting system, cooling system, lubrication system, ignition system (for gasoline vehicles), and fuel supply system. The crankshaft-connecting rod mechanism provides a combustion chamber, converting the expansion pressure of the gas generated after fuel combustion acting on the piston top into the rotational torque of the crankshaft. The following are precautions for gasoline engines: 1. Note one: To transition the engine from a stationary state to an operational state, it is necessary to first rotate the engine's crankshaft with an external force, causing the piston to perform reciprocating motion. The combustible mixture in the cylinder burns and expands to do work, pushing the piston downward to rotate the crankshaft, enabling the engine to run on its own and the working cycle to proceed automatically. 2. Note two: The entire process from when the crankshaft begins to rotate under external force until the engine starts to idle automatically is called engine starting; the device required to complete the starting process is called the engine starting system.
From my driving experience, the two major mechanisms of an engine include the crank-connecting rod mechanism and the valve train. The crank-connecting rod is responsible for converting the up-and-down motion of the pistons into the rotational power output of the crankshaft, like the push-back feeling when you step on the accelerator; the valve train controls the opening and closing timing of the intake and exhaust valves, ensuring fresh air comes in and exhaust gases are expelled. The five major systems are the fuel supply system, which delivers fuel or gas into the cylinders; the ignition system, which ignites the mixture after compression to start combustion; the cooling system, which uses fans and water circulation to prevent engine overheating; the lubrication system, which adds oil to protect parts and reduce friction; and the starting system, which uses an electric motor to turn over and start the entire machine. Among these components, cooling and lubrication issues are the most common—for example, traffic jams in summer can easily trigger the high-temperature warning light. Timely maintenance can prevent major repairs. I once broke down on the highway due to a cooling system failure, which made me pay more attention to regularly checking the radiator and oil levels.
