How does the internal combustion engine in a car work

How does an automobile work? The original principle? Now? What are the parts that make up an automobile?

How many parts are there in an automobile? How are the parts related to each other and what is the role of each?

Oo spitting bubbles of fish oO Answer:1 Popularity:3 Solution time:2007-12-24 23:29 whistleblowing First, the basic theory

Gasoline engines convert the energy of gasoline into kinetic energy to drive the car, the easiest way to get kinetic energy is by burning gasoline inside the engine. Therefore, automobile engines are internal combustion engines ---- combustion occurs inside the engine.

There are two things to note:

1. There are other types of internal combustion engines as well, such as diesel engines and gas turbines, each with their own advantages and disadvantages.

2. There are also external combustion engines. The steam engine used in early trains and ships is a typical external combustion engine. Fuel (coal, wood, oil) is burned outside the engine to produce steam, and then the steam goes inside the engine to produce power. Internal combustion engines are quite a bit more efficient and much smaller than external combustion engines for the same power. That's why modern cars don't use steam engines.

In contrast, internal combustion engines are more efficient than external combustion engines, cheaper than gas turbines, and easier to add fuel to than electric cars. These advantages have led most modern cars to use reciprocating internal combustion engines.

Two, combustion is the key

Automobile engines generally use 4-stroke. (Mazda's rotor engine will not be discussed here, Auto Illustrated has been introduced)

4 strokes are: intake, compression, combustion, exhaust. To complete these 4 processes, the engine completes one cycle (2 revolutions).

Understanding the 4 strokes

The piston, which consists of a rod connected to the crankshaft, proceeds as follows:

1. The piston starts at the top, the intake valve opens, and the piston moves downward to draw in the oil/gas mixture

2. The piston moves upward to compress the mixture of oil/gas, making the explosion more powerful.

3. When the piston reaches the top, the spark plug to release a spark to ignite the gas mixture, the explosion makes the piston downward movement again.

4. When the piston reaches the bottom, the exhaust valve opens, the piston moves upward, and exhaust gases exit the cylinder through the exhaust pipe.

Note: The final motion produced by an internal combustion engine is rotational, and the linear reciprocating motion of the piston is ultimately converted to rotation by the crankshaft so that it can drive the car tires.

Three, the number of cylinders

The core component of the engine is the cylinder, the piston reciprocating motion in the cylinder, described above is a single-cylinder motion process, while the actual application of the engine are more than one cylinder (4 cylinders, 6 cylinders, 8 cylinders is more common). We usually categorize engines by the arrangement of the cylinders: inline, V or horizontally opposed (and now, of course, the Volkswagen Group's W model, which actually consists of two Vs).

The different arrangements give the engines their own advantages and disadvantages in terms of smoothness, manufacturing costs and appearance, and are fitted to the respective cars.

Four, displacement

The compression and combustion of the mixture is carried out in the combustion chamber, the piston reciprocates, you can see the change in the volume of the combustion chamber, the difference between the maximum value and the minimum value is the displacement, measured in liters (L) or milliliters (CC). The displacement of a car is usually between 1.5L and 4.0L. With a displacement of 0.5L per cylinder, a 4-cylinder has a displacement of 2.0L, and if the V-arrangement has 6 cylinders, it is a V6 3.0 liter. In general, displacement indicates the amount of engine power.

Influencing Factors

1.1 Structure Manufacturing

The design, manufacturing and assembly of the various components of the automobile directly affect the performance of the engine. These factors mainly come from the automobile manufacturers and have little to do with the user. Each car manufacturer's special repair station should be the engine in use in some of the typical problems feedback to the manufacturing plant, in order to facilitate the improvement.

1.2 Use

Correct use is necessary to extend the service life of the engine.

1.2.1 Load selection

Engine load directly affects the strength and life of its components, increase the load, the working load of the various assemblies also increased, the amount of wear and tear increases; if the vehicle is the first drive, the wear and tear will be greater. New or overhauled vehicles, in order to limit the maximum speed of the initial period, reduce the load, prolong the life of the engine, generally in the carburetor to install speed limiters. If the speed limiting plate is removed prematurely, it will lead to premature engine rattling, oil leakage, air leakage and power loss, shortening the engine life cycle.

1.2.2 Fuel and lubricant selection

The selection of fuel must be in line with the specified grade of the car, prohibit the use of low grade fuel, otherwise the engine will produce a shock, so that the parts are subjected to a strong impact and make the parts of the additional load increase, thereby accelerating the wear of the parts. Because of the high temperature, high pressure and shock waves generated by the burst will also destroy the lubricant film on the cylinder wall, deteriorating the lubrication of the parts. Tests have shown that an engine in the burst and no burst of vibration under the work of 200 h, after determining the average wear and tear of the upper part of the cylinder when there is a burst of vibration is more than 2 times the amount of no burst of vibration. In addition, the fuel containing impurities exceeds the standard, the same will accelerate the wear and corrosion of machine parts.

The choice of lubricating oil should also meet the needs of the engine, if the engine lubricant viscosity is low, the lubricant pressure is low, can not form a film, resulting in boundary friction or dry friction; if the lubricating oil viscosity is too large, the liquidity is poor, not conducive to the cold start, and at the same time the lubricating oil through the oil filter to the lubricated parts of the long time to make the start-up wear and tear increased.

Lubricating oil filling should be appropriate, the oil level is too high, not only will increase the resistance to movement, reduce power, and will make the lubricating oil into the cylinder combustion, resulting in too much carbon; and lubricating oil is too little, the oil pressure is low, it is difficult to form a film of oil, but also cause dry friction or boundary friction, so that the wear increases, the bearings produce noise, and even the occurrence of pulling the cylinder and burn the tile and other serious accidents.

1.2.3 Cold start and cooling water temperature

When the cold start, especially in winter start the vehicle, should try to use preheating measures or cold cranking slow turn low-speed warming approach, prohibit the throttle. Because the engine cold start, the viscosity of the lubricant is high, the time to reach the lubrication part of the milling aaS ferocious persistent present っ sole? Flattering? 5 ℃, 2 min after the start, the lubricant can flow to the connecting rod bearings and cylinder head on the moving parts, in this period of time, such as slamming on the throttle, the engine speed will rise rapidly, the lubricant does not reach the parts of the formation of dry friction, exacerbate wear and tear.

When the engine temperature is too high, the lubricant becomes thin, can not form a good lubricant film, the same will increase the wear and tear of the parts, but also very easy to produce shock. However, the water temperature should not be high and blindly remove the thermostat to make the engine work at low temperatures for a long time, which will also cause excessive wear and tear of the engine.

1.3 Road

The quality of the road surface on the speed of play, fuel consumption and wear and tear has a great impact, if the road surface is gravel or muddy road, driving resistance is constantly changing; in the resistance is large, the engine is working in a large load conditions, the pressure in the cylinder increases, wear and tear.

1.4 Climate

In winter, due to the low viscosity of the lubricant, into the lubrication part of the slow, so that the engine dry friction for a long time; in the hot summer, the car parts are in a hot state, in the ambient temperature of 40 ℃, will seriously affect the performance of the electrical components, so that the ignition system can not work properly; in addition, due to high temperatures, lubricating oil thinning, the oil film is difficult to form. Make the engine dry friction tendency to increase.

1.5 Driving

The skillfulness or otherwise of the driving technique also affects the performance and service life of the engine.

1.5.1 Selection of gear

The driving should master the "high-speed gear is not hard to support", otherwise the engine long time high-speed operation, so that the engine has no spare capacity, poor stability, torsion vibration and impact, resulting in damage to the machine parts; "low-speed gear is not hard to rush! ", otherwise the engine temperature increases, resulting in premature combustion and deflagration and other phenomena, resulting in early engine wear.

1.5.2 Selection of speed

Speed has a greater impact on the amount of wear and tear of the various moving parts, the amount of wear and tear depends on the relative speed of movement, positive pressure and friction coefficient. At high speed, the piston average linear velocity is larger, so the relative cylinder wear is large, especially when the combustion is bad, carbon particles form abrasive particles to increase the wear. When the speed is low, due to low lubricant pressure, oil film rigidity is small, poor lubrication conditions, will also increase wear.

1.6 Maintenance quality

Strengthening the maintenance of the engine is an important step to extend the life of the engine. In addition to the daily inspection and maintenance of the project, we should focus on the engine's "entrance" off, keep the "three filters" (oil filter, car filter, air filter) clean. If the "three filters" failure, the dust in the air and impurities in the lubricating oil and fuel into a large number of cylinders, thereby exacerbating the abrasive wear. Practice shows that if the air filter failure, if the northwest or north China in our country driving a day into the cylinder dust can be as high as 30 g, the cylinder wear will be 100 times larger than normal.

2 Countermeasures

2.1 Correctly drive the vehicle

Shift gears at the right time; avoid overloading; as far as possible to reduce the number of cold starts of the engine; to maintain a certain temperature of the cooling water; reasonable choice of speed.

2.2 Reasonable selection of fuel and lubricating oil

2.3 Strengthen the engine maintenance and regular maintenance

So increasing the number of cylinders or increasing the volume of the combustion chamber of each cylinder can get more power.

V. Other Parts of the Engine

Camshaft Controls the opening and closing of the intake and exhaust valves

Spark Plugs Spark plugs put out sparks to ignite the oil-gas mixture, causing an explosion to occur. The spark must be released at the right time.

VALVES The inlet and outlet valves are opened at the proper times to draw in the gas mixture and discharge the exhaust gases, respectively. During compression and

combustion, both valves are closed to ensure a tight seal in the combustion chamber.

Piston rings Provide a seal in the cylinder wall and piston:

1. Prevents leakage of the oil-gas mixture and exhaust gases into the lubrication tank during compression and combustion.

2. Prevent lubricant from entering the cylinder and burning.

Most "oil-burning" cars have old engines: the piston rings are no longer sealed (smoke from the tailpipe)

The piston rod connects the piston rings to the crankshaft, allowing the piston and crankshaft to maintain their respective motions.

The lubrication groove surrounds the crankshaft and contains a considerable amount of oil.