Types of pistons What is a piston and what does an engine piston group consist of? Purpose and types of pistons

I think any motorist most likely knows what a piston looks like. But on this, as a rule, knowledge about the main part of the engine ends. Therefore, let's fill in the gap and talk about the purpose of the piston, its design features and materials for manufacturing.

What does a piston look like? Complex detail. This confirms this fact - very few car manufacturers themselves manufacture pistons, entrusting this to specialized manufacturers.

And yet - this is the main link in the process of converting the chemical energy of the fuel into heat, and then into mechanical.

The piston, I would say, is a beautiful piece of cylindrical shape, it performs breathtaking reciprocating movements in the cylinder, takes over high temperatures and changes in gas pressure, turning it all into mechanical work.

That is, this is what the piston does:

• takes on the pressure of gases from the combustion chamber and transfers this pressure to the crankshaft of the engine;
• provides a tough process of microexplosions in the cylinder, while hermetically isolating the over-piston cavity from the under-piston space, preventing gases from entering the crater, and lubricating oil from entering the combustion chamber.

What does the piston look like? Design

The scheme was prepared based on the materials of Volkswagen AG

1. piston head;
2. finger;
3. retaining ring;
4. bosses;
5. connecting rod head;
6. skirt; steel insert;
7. trapezoidal compression ring;
8. conical undercut compression ring;
9. oil scraper ring with spring expander

The piston consists of a bottom, a sealing part with piston rings to create compression and oil removal, and a guide part (skirt).

In the middle part of the piston (skirt area) there are bosses with holes for the pin and circlips.

Working bottom

Do you know what the piston looks like and what this part is called? This part of the part serves to receive force from the gas pressure in the combustion chamber and is called working bottom . Its shape depends on the geometry of this chamber and the placement of the valves.

In the case when the bottom is concave, the shape of the combustion chamber resembles a spherical one. This increases its surface, but leads to an increase in the formation of soot, and the strength of the concave bottom is lower than that of the flat one.

The convex bottom makes the combustion chamber slit-shaped, which leads to a deterioration in the process of swirling the mixture and cooling the bottom itself, although carbon formation is reduced.

In addition, this shape of the bottom reduces the mass of the piston with sufficient strength.

The flat bottom in terms of its performance is an intermediate option between the two previous ones and is more often used in carburetor engines.

In diesel engines, the variety of bottom shapes is even greater, they vary depending on the compression ratio, the method of mixture formation, the location of the nozzles and many other factors.

Sealing sector

The piston head seals the movable connection of the piston with the cylinder due to the piston rings, which are installed in special grooves. Compression rings are inserted in the upper grooves, and an oil scraper ring is inserted in the lower grooves. There are through holes in the groove for the oil scraper ring, through which excess oil is drained into the internal cavity of the piston.

Guide skirt, bosses

The section of the piston located below the oil scraper ring is called the piston skirt, and also the trunk or guide part.

Its function is to hold the piston in the right direction and perceive lateral loads.

FROM inside there are tides on the skirt - bosses, holes for the piston pin are drilled in them. And for its fixation, grooves are machined in the holes, for locking the finger with retaining rings.

What will the metallurgists say?

Since the part works in unbearable conditions, rather stringent requirements are imposed on metals for its manufacture:

• to reduce inertial loads, the material must have a low specific gravity with sufficient strength;
• low coefficient of thermal expansion;
• preservation of physical properties (strength) at elevated temperatures;
• significant thermal conductivity and heat capacity;
• minimum coefficient of friction paired with the material of the cylinder wall;
• significant wear resistance;
• no fatigue failure of the material under load;
• low price, general availability and ease of mechanical and other types of processing in the production process.

It is clear that a metal that fully meets the listed requirements simply does not exist. Therefore, for mass automobile engines, pistons are made mainly from two materials - cast iron and aluminum alloys, and to be precise, from silumin alloys containing aluminum and silicon.

Cast iron variant

Cast iron has many advantages, it is hard, tolerates elevated temperatures well, has optimal wear resistance, and has a low coefficient of friction (a pair of cast iron - cast iron). And its coefficient of thermal expansion is lower than that of an aluminum piston.

But there are also disadvantages: low thermal conductivity, which is why the temperature of the bottom of the cast-iron piston is higher than that of the aluminum counterpart.

But the main disadvantage of cast iron is its significant density, which means weight. To increase the power and efficiency of the engine, designers usually increase the speed, but heavy cast iron pistons do not allow this due to high inertial loads.

Therefore, for modern automobile engines, both gasoline and diesel, aluminum pistons are cast.

Aluminum variant

Aluminum has a much lower weight than cast iron, but since it is softer, the thickness of the piston walls has to be increased, as a result, the weight of the piston becomes only 30 to 40 percent lighter in relation to cast iron.

In addition, aluminum has an increased thermal expansion coefficient, so heat-stabilizing steel plates have to be fused into the body of the part, and increased gaps have to be made.

Aluminum has a rather low coefficient of friction (pair: aluminum - cast iron), which is good for the operation of aluminum pistons in engines with a cast iron cylinder block or cast iron liners.

On modern engines of German brands - Audi, Volkswagen, Mercedes, there are no cast-iron liners. The aluminum cylinders there are processed in a special way, so that the wall surface is very hard and has a wear resistance even higher than when installing cast iron sleeves.

And in order to reduce friction in a pair of aluminum - aluminum, ironing of the surface of the skirt is carried out. Thus, the rejection of cast iron liners greatly reduces the weight of the cylinder block.

In silicon-aluminum alloys, from which the pistons of the bulk of automobile engines are made, copper, nickel and other metals are added to improve performance.

The pistons of production cars are produced by casting, and on forced engines, products made by hot stamping are used. This improves the structure of the material - increases strength and resistance to wear. True, it is impossible to mount steel thermostatic plates in the stamped version.

That's probably all. You have received the necessary minimum knowledge of what a piston looks like, its design and operating conditions.

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The piston occupies a central place in the process of converting fuel energy into thermal and mechanical energy. Let's talk about engine pistons, what they are and how they work.

What it is?

A piston is a cylindrical part that reciprocates inside an engine cylinder. Needed to change gas pressure into mechanical work, or vice versa - reciprocating movement into a change in pressure. Those. it transmits to the connecting rod the force arising from the gas pressure and ensures the flow of all cycles of the working cycle. It looks like an inverted glass and consists of a bottom, a head, a guide part (skirt).

Gasoline engines use flat-bottom pistons due to ease of manufacture and less heat during operation. Although some modern cars make special recesses for the valves. This is necessary so that when the timing belt breaks, the pistons and valves do not meet and do not entail a serious repair. The bottom of the diesel piston is made with a recess, which depends on the degree of mixture formation and the location of the valves and injectors. With this shape of the bottom, the air is better mixed with the fuel entering the cylinder.

The piston is exposed to high temperatures and pressures. It moves at high speed inside the cylinder. Therefore, initially for automobile engines they were cast from cast iron. With the development of technology, aluminum began to be used, because. it gave the following advantages: an increase in speed and power, less stress on parts, better heat transfer.

Since then, the power of the motors has increased many times. The temperature and pressure in the cylinders of modern automobile engines (especially diesel engines) have become such that aluminum has reached its limit of strength. Therefore, in recent years, such motors are equipped with steel pistons that can confidently withstand increased loads. They are lighter than aluminum due to thinner walls and lower compression height, i.e. distance from the bottom to the axis of the aluminum pin. And the steel pistons are not cast, but prefabricated.

Among other things, reducing the vertical dimensions of the piston with the same cylinder block makes it possible to lengthen the connecting rods. This will reduce the lateral loads in the piston-cylinder pair, which will positively affect fuel consumption and engine life. Or, without changing the connecting rods and crankshaft, you can shorten the cylinder block. Thus, we will lighten the engine.

What are the requirements?

• The piston, moving in the cylinder, allows the compressed gases, the product of fuel combustion, to expand and perform mechanical work. Therefore, it must be resistant to high temperature, gas pressure and reliably seal the cylinder bore.
• It must best meet the requirements of the friction pair in order to minimize mechanical losses and, as a result, wear.
• Experiencing loads from the combustion chamber and reaction from the connecting rod, it must withstand mechanical stress.
• When reciprocating at high speed, it should load the crank mechanism with inertial forces as little as possible.

Main purpose

Fuel, burning in the space above the piston, releases a huge amount of heat in each cycle of the engine. The temperature of the burnt gases reaches 2000 degrees. They will transfer only part of the energy to the moving parts of the motor, everything else in the form of heat will heat the engine. What remains, together with the exhaust gases, will fly into the pipe. Therefore, if we do not cool the piston, it will melt after a while. This is an important point for understanding the operating conditions of the piston group.

Once again, we repeat the well-known fact that the heat flow is directed from more heated bodies to less heated ones.

The most heated is the working fluid, or, in other words, the gases in the combustion chamber. It is quite clear that the heat will be transferred to the surrounding air - the coldest. Air, washing the radiator and engine housing, will cool the coolant, cylinder block and head housing. It remains to find a bridge through which the piston gives off its heat to the block and antifreeze. There are four ways for this.

So, the first path providing the most flow, are piston rings. Moreover, the first ring plays a major role, as it is located closer to the bottom. This is the shortest path to the coolant through the cylinder wall. The rings are simultaneously pressed against both the piston grooves and against the cylinder wall. They provide more than 50% of the heat flow.

The second way is less obvious. The second coolant in the engine is oil. Having access to the most heated places of the engine, oil mist carries away and gives to the oil pan a significant part of the heat from the hottest points. In the case of using oil nozzles that direct the jet to the inner surface of the piston bottom, the share of oil in heat exchange can reach 30 - 40%. It is clear that when loading the oil with the function of a coolant, we must take care to cool it down. Otherwise, overheated oil may lose its properties. Also, the higher the temperature of the oil, the less heat it can carry.

Third way. Part of the heat is taken away for heating by the fresh air-fuel mixture that enters the cylinder. The amount of fresh mixture and the amount of heat that it takes away depends on the mode of operation and the degree of opening of the throttle. It should be noted that the heat obtained during combustion is also proportional to the charge. Therefore, this cooling path is impulsive; it is fast and highly efficient due to the fact that the heat is taken from the side from which the piston is heated.

Due to its greater importance, close attention should be paid to the transfer of heat through the piston rings. It is clear that if we block this path, then it is unlikely that the engine will withstand any long forced regimes. The temperature will rise, the piston material will "float", and the engine will collapse.

Recall such a characteristic as compression. Let us imagine that the ring does not adhere along its entire length to the wall of the cylinder. Then the burnt gases, breaking through into the gap, will create a barrier that prevents the transfer of heat from the piston through the ring to the cylinder wall. This is the same as if you closed part of the radiator and deprived it of the ability to be cooled by air.

The picture is more terrible if the ring does not have close contact with the groove. In those places where gases have the opportunity to flow past the ring through the groove, the piston section is deprived of the opportunity to cool. As a result, burnout and chipping of the part adjacent to the leak.

How many rings do you need for a piston? From a mechanical point of view, the fewer rings, the better. The narrower they are, the lower the losses in the piston group. With a decrease in their number and height, the conditions for cooling the piston worsen, increasing the thermal resistance of the bottom - ring - cylinder wall. Therefore, the choice of design is always a compromise.

The piston occupies a central place in the process of converting the chemical energy of the fuel into thermal and mechanical energy. Let's talk about pistons of an internal combustion engine, what it is and the main purpose in the work.

WHAT IS AN ENGINE PISTON?

Engine piston- this is a cylindrical part that reciprocates inside the cylinder and serves to convert a change in the pressure of a gas, vapor or liquid into mechanical work, or vice versa - a reciprocating movement into a change in pressure. Initially, pistons for automotive internal combustion engines were cast from cast iron. With the development of technology, aluminum began to be used, because. it gave the following advantages: an increase in speed and power, less stress on parts, better heat transfer.

Since then, engine power has increased many times over, the temperature and pressure in the cylinders of modern automobile engines (especially diesel engines) have become such that aluminum has reached its limit of strength. Therefore, in recent years, such motors are equipped with steel pistons that can confidently withstand increased loads. They are lighter than aluminum due to thinner walls and lower compression height, i.e. distance from the bottom to the axis of the aluminum pin. And the steel pistons are not cast, but prefabricated.
Among other things, reducing the vertical dimensions of the piston with the same cylinder block makes it possible to lengthen the connecting rods. This will reduce lateral loads in the piston-cylinder pair, which will positively affect fuel consumption and engine life. Or, without changing the connecting rods and crankshaft, you can shorten the cylinder block and thus lighten the engine

The piston performs a number of important functions:

• ensures the transfer of mechanical forces to the connecting rod;
• is responsible for sealing the fuel combustion chamber;
• ensures timely removal of excess heat from the combustion chamber

The work of the piston takes place in difficult and in many ways dangerous conditions - at elevated temperatures and increased loads, therefore it is especially important that pistons for engines are distinguished by efficiency, reliability and wear resistance. That is why light but heavy-duty materials are used for their production - heat-resistant aluminum or steel alloys. Pistons are made by two methods - casting or stamping.

Extreme conditions dictate piston material

The piston is operated under extreme conditions, the characteristic features of which are high: pressure, inertial loads and temperatures. That is why the main requirements for materials for its manufacture include:

• high mechanical strength;
• good thermal conductivity;
• low density;
• insignificant coefficient of linear expansion, antifriction properties;
• good corrosion resistance.

The required parameters correspond to special aluminum alloys, which are distinguished by strength, heat resistance and lightness. Less commonly, gray cast irons and steel alloys are used in the manufacture of pistons.
Pistons can be:

• cast;
• forged.

In the first version, they are made by injection molding. Forged ones are made by stamping from an aluminum alloy with a small addition of silicon (on average, about 15%), which significantly increases their strength and reduces the degree of expansion of the piston in the operating temperature range.

Piston design

The engine piston has a fairly simple design, which consists of the following parts:

1. ICE piston head
2. piston pin
3. Retaining ring
4. Boss
5. connecting rod
6. Steel insert
7. Compression ring one
8. Second compression ring
9. Oil scraper ring

The design features of the piston in most cases depend on the type of engine, the shape of its combustion chamber and the type of fuel that is used.

Bottom

The bottom can have a different shape depending on the functions it performs - flat, concave and convex. The concave shape of the bottom provides more efficient operation of the combustion chamber, however, this contributes to more deposits during the combustion of fuel. The convex shape of the bottom improves the performance of the piston, but at the same time reduces the efficiency of the combustion process of the fuel mixture in the chamber.

Piston rings

Below the bottom are special grooves (grooves) for installing piston rings. The distance from the bottom to the first compression ring is called the firing zone.

Piston rings are responsible for a reliable connection between the cylinder and the piston. They provide reliable tightness due to a snug fit to the cylinder walls, which is accompanied by an intense friction process. Engine oil is used to reduce friction. Piston rings are made from cast iron.

The number of piston rings that can be installed in a piston depends on the type of engine used and its purpose. Often systems with one oil scraper ring and two compression rings (first and second) are installed.

PISTON TYPES

In internal combustion engines, two types of pistons are used, which differ in their design - one-piece and composite.

One-piece parts are made by casting followed by machining. In the process of casting, a blank is created from metal, which is given the general shape of the part. Further, on metalworking machines, working surfaces are processed in the resulting workpiece, grooves are cut for rings, technological holes and recesses are made.

In the composite elements, the head and the skirt are separated, and they are assembled into a single structure during installation on the engine. Moreover, the assembly in one piece is carried out by connecting the piston to the connecting rod. For this, in addition to the holes for the piston pin in the skirt, there are special lugs on the head.

The advantage of composite pistons is the possibility of combining materials of manufacture, which increases the performance of the part.

Removal of excess heat from the piston

In addition to significant mechanical stresses, the piston is also subjected to the negative effects of extremely high temperatures. Heat is removed from the piston group:

• cooling system from the cylinder walls;
• the internal cavity of the piston, then - the piston pin and connecting rod, as well as the oil circulating in the lubrication system;
• partially cold air-fuel mixture supplied to the cylinders.

From the inner surface of the piston, its cooling is carried out using:

Oil scraper ring and compression rings

The oil scraper ring ensures the timely removal of excess oil from the inner walls of the cylinder, and the compression rings prevent gases from entering the crankcase.

The compression ring, located first, receives most of the inertial loads during piston operation.

To reduce loads in many engines, a steel insert is installed in the annular groove, which increases the strength and degree of compression of the ring. Compression type rings can be made in the form of a trapezoid, barrel, cone, with a cutout.

The oil scraper ring in most cases is equipped with many holes for oil drainage, sometimes with a spring expander.

piston pin

This is a tubular part that is responsible for the reliable connection of the piston to the connecting rod. Made from steel alloy. When installing the piston pin in the bosses, it is tightly fixed with special retaining rings.

The piston, piston pin and rings together form the so-called engine piston group.

Skirt

The guide part of the piston device, which can be made in the form of a cone or barrel. The piston skirt is equipped with two bosses for connection with the piston pin.

To reduce friction losses, a thin layer of an antifriction agent is applied to the surface of the skirt (often graphite or molybdenum disulfide is used). The lower part of the skirt is equipped with an oil scraper ring.

A mandatory process for the operation of a piston device is its cooling, which can be carried out by the following methods:

• spraying oil through the holes in the connecting rod or nozzle;
• the movement of oil along the coil in the piston head;
• supplying oil to the area of ​​the rings through the annular channel;
• oil mist

Sealing part

The sealing part and the bottom are connected in the form of a piston head. In this part of the device there are piston rings - oil scraper and compression. The channels for the rings have small holes through which the used oil enters the piston and then flows into the crankcase.

In general, the piston of an internal combustion engine is one of the most heavily loaded parts, which is subjected to strong dynamic and at the same time thermal effects. This imposes increased requirements both on the materials used in the production of pistons and on the quality of their manufacture.

The engine of any modern machine is characterized by a high complexity of design and a large number of components. Despite such high complexity, the principle of operation of the internal combustion engine is based on basic concepts that are relevant for a car of any class and year of manufacture. In this article, we will look at one of the key elements - the piston of an internal combustion engine - and talk about what it is for and what it consists of.

Structure

The piston of a 4-stroke engine has a rather complex structure and, thus, the entire device includes several components. This allows you to give the machine optimal technical characteristics, as well as make the 4-stroke engine more resistant to stress, and therefore durable.

The main part that makes up the piston of a four-stroke internal combustion engine is its bottom. The bottom is slightly smaller in diameter than the diameter of the cylinder, which is explained by the presence of compression and oil scraper rings. The bottom of the piston of any diameter can have a different shape and description. Thus, it may have a concave shape, and the recess itself may have a different configuration.

The main purpose of the bottom in the piston device in the design of a four-stroke engine is interaction with fuel vapors, which, when burned, push the piston and make it move throughout the entire period of operation. The shape of the bottom in the piston of a 4-stroke engine is dictated by a large number of factors. Usually it depends on the number of candles, power, piston diameter and many other nuances.

In addition to the bottom, in the piston, no matter how many millimeters it has in diameter, there is always a sealing part, which includes devices such as compression and oil scraper rings. Compression rings are inserted into special machined grooves, which are slightly different in diameter from the diameter of the piston head. Their task is not to allow the used and fresh mixture to mix, and also to maintain pressure during fuel combustion.

What is the purpose of compression rings? Compression rings in the piston of a 4-stroke engine are necessary so that the efficiency of the engine is maximum, and all the energy of the burned fuel is directed to moving the piston. For this reason, serious and strict requirements are imposed on the materials from which such rings are made in a four-stroke engine.

In addition to compression, the piston of a 4-stroke engine is necessarily equipped with such structures as oil scraper rings, which have a slightly larger diameter than the piston itself. They are necessary so that the lubricant, which constantly circulates in the motor to prevent friction and overheating, remains on the rubbing surfaces in the right amount and does not accumulate in the combustion chamber. Thanks to this, oil carbon deposits are avoided, and lubricant consumption is drastically reduced.

How it works?

The stroke of a four-stroke engine is the cycle during which the crankshaft of the engine makes one complete revolution. During this time, the fuel mixture, which is supplied by a carburetor or injector, burns out completely and is discharged into the exhaust manifold, where it passes through the muffler and dissipates into the environment.

The stroke of the piston is characterized exclusively by the movement up and down. This state of affairs applies to four-stroke, and all other types of motors. As already mentioned, the translational movement is caused solely by combustion processes that occur at high temperatures.

When the piston stroke is in the vertical direction, the crankshaft to which it is connected rotates. For this reason, designers and engineers introduced a crank that allows you to set the shaft in motion and make it rotate the wheels all the time while the four-stroke engine is running.

Usually, the crank is hinged to the piston head: the piston stroke is free enough so that the crank moves at an acute angle relative to the axis of symmetry and is in constant motion. The connecting rod is a small metal rod, which is equipped with hinge inserts at both ends. On the one hand, the connecting rod moves relative to the piston, which moves up and down.

From the opposite end, the connecting rod is movably fixed to the crankshaft. Between the connecting rod and the shaft are the so-called liners, the device of which allows you to endure high temperatures and not wear out even at peak loads. When the time comes for repair, the liners are replaced with new ones, and there may be several such maintenance cycles before replacing the crankshaft.

Production material

The piston of a 4-stroke engine, or rather, the material from which it is made, must meet a large number of requirements. For example, the material must be resistant to severe temperature overloads, because fuel combustion causes severe overheating, for which most existing materials are not ready.

In addition, such materials should have a low density. This is necessary to make the piston as light as possible in order to reduce the load on the parts and the total fuel consumption.

What materials meet such requirements and are widely used on four-stroke internal combustion engines? The most common such material is cast iron. Being relatively inexpensive, it does an excellent job with all its tasks and withstands high temperatures. As practice shows, the resource of such a part is quite high, and the reliability meets all the requirements, so a cast iron piston can be found on most cars.

Nevertheless, progress does not stand still, and aluminum has replaced cast iron, or rather, its special variety. The advantage of this material is that it is noticeably lighter, but in terms of strength it is in no way inferior to the usual cast iron. For this reason, it is aluminum pistons that are put on sports cars in four-stroke engines. This decision allowed to increase power, increase resource and reduce fuel consumption. It is worth noting that aluminum pistons are also often installed on ordinary civilian vehicles, which indicates their obvious advantages.

Summary

The engine piston is an important part, without which the normal operation of the motor would be impossible. In this regard, global automakers are trying to bring existing solutions closer to perfection. This allows you to achieve better performance with a higher resource, which indicates that progress does not stand still.

Most cars are forced to move by a piston internal combustion engine (abbreviated internal combustion engine) with a crank mechanism. This design has become widespread due to the low cost and manufacturability of production, relatively small dimensions and weight.

According to the type of fuel used, internal combustion engines can be divided into gasoline and diesel. I must say that gasoline engines work great on. This division directly affects the design of the engine.

How does a piston internal combustion engine work?

The basis of its design is the cylinder block. This is a body cast from cast iron, aluminum or sometimes magnesium alloy. Most of the mechanisms and parts of other engine systems are attached specifically to the cylinder block, or located inside it.

Another major part of the engine is its head. It is located at the top of the cylinder block. The head also houses parts of the engine systems.

A pallet is attached to the cylinder block from below. If this part takes the load when the engine is running, it is often called the oil pan, or crankcase.

All engine systems

1. crank mechanism;
2. gas distribution mechanism;
3. supply system;
4. cooling system;
5. Lubrication system;
6. ignition system;
7. engine management system.

crank mechanism consists of piston, cylinder liner, connecting rod and crankshaft.

Crank mechanism:
1. Oil scraper ring expander. 2. Piston oil scraper ring. 3. Compression ring, third. 4. Compression ring, second. 5. Compression ring, top. 6. Piston. 7. Retaining ring. 8. Piston pin. 9. Connecting rod bushing. 10. Connecting rod. 11. Connecting rod cap. 12. Insert of the lower head of the connecting rod. 13. Connecting rod cap bolt, short. 14. Connecting rod cap bolt, long. 15. Drive gear. 16. Plug of the oil channel of the crankpin. 17. Crankshaft bearing shell, upper. 18. Gear ring. 19. Bolts. 20. Flywheel. 21. Pins. 22. Bolts. 23. Oil deflector, rear. 24. Crankshaft rear bearing cap. 25. Pins. 26. Thrust bearing half ring. 27. Crankshaft bearing shell, lower. 28. Counterweight of the crankshaft. 29. Screw. 30. Crankshaft bearing cap. 31. Coupling bolt. 32. A bolt of fastening of a cover of the bearing. 33. Crankshaft. 34. Counterweight, front. 35. Oil slinger, front. 36. Lock nut. 37. Pulley. 38. Bolts.

The piston is located inside the cylinder liner. With the help of a piston pin, it is connected to a connecting rod, the lower head of which is attached to the connecting rod journal of the crankshaft. The cylinder liner is a hole in the block, or a cast iron sleeve inserted into the block.

Cylinder liner with block

The cylinder liner is closed with a head on top. The crankshaft is also attached to the block at the bottom. The mechanism converts the rectilinear movement of the piston into the rotational movement of the crankshaft. The same rotation that ultimately makes the wheels of the car spin.

Gas distribution mechanism is responsible for supplying a mixture of fuel and air vapors to the space above the piston and removing combustion products through valves that open strictly at a certain point in time.

The power system is primarily responsible for the preparation of a combustible mixture of the desired composition. The devices of the system store the fuel, purify it, mix it with air in such a way as to ensure the preparation of a mixture of the desired composition and quantity. The system is also responsible for removing fuel combustion products from the engine.

When the engine is running, thermal energy in an amount greater than the engine is able to convert into mechanical energy. Unfortunately, the so-called thermal efficiency of even the best examples of modern engines does not exceed 40%. Therefore, a large amount of "extra" heat has to be dissipated in the surrounding space. This is exactly what it does, removes heat and maintains a stable operating temperature of the engine.

Lubrication system . This is just the case: “If you don’t grease, you won’t go.” Internal combustion engines have a large number of friction units and so-called plain bearings: there is a hole, the shaft rotates in it. There will be no lubrication, the assembly will fail from friction and overheating.

Ignition system designed to set fire, strictly at a certain point in time, a mixture of fuel and air in the space above the piston. there is no such system. There, the fuel spontaneously ignites under certain conditions.

Video:

Engine management system with electronic block control (ECU) controls the engine systems and coordinates their work. First of all, this is the preparation of a mixture of the desired composition and timely ignition of it in the engine cylinders.