Internal combustion engines
Training center "ONikS"
Internal combustion engine device
1 - cylinder head;
2 - cylinder;
3 - piston;
4 - piston rings;
5 - piston pin;
7 - crankshaft;
8 - flywheel;
9 - crank;
10 - a camshaft;
11 - a cam of a camshaft;
12 - lever;
13 - valve;
14 - spark plug
The upper extreme position of the piston in the cylinder is called top dead center (TDC)
Internal combustion engine parameters
The lower extreme position of the piston in the cylinder is called the bottom dead center.
Internal combustion engine parameters
The distance traveled by the piston from one dead center to another is called
piston stroke S .
Internal combustion engine parameters
Volume V from above the piston located in the. m., called combustion chamber volume
Internal combustion engine parameters
Volume V p above the piston located in n. m.t. is called
full cylinder volume .
Internal combustion engine parameters
Volume Vр, released by the piston when it moves from v. m. t. to n. m., called working volume of the cylinder .
Internal combustion engine parameters
Cylinder displacement
Where: D - cylinder diameter;
S - piston stroke.
Internal combustion engine parameters
Full cylinder volume
V c + V h \u003d V n
Internal combustion engine parameters
Compression ratio
Duty cycles of internal combustion engines
4-stroke
2-stroke
engine .
The first measure - inlet .
The piston moves from to. m. t. to n. m., the inlet valve is open, the outlet valve is closed. A vacuum of 0.7-0.9 kgf / cm is created in the cylinder and a combustible mixture consisting of gasoline vapors and air enters the cylinder.
Mix temperature at the end of the inlet
75-125 ° C.
The working cycle of a four-stroke carburetor engine .
Second measure- compression .
The piston moves from the borehole. to wmt, both valves are closed. The pressure and temperature of the working mixture increase, reaching by the end of the stroke, respectively
9-15 kgf / cm 2 and 35O-50O ° C.
The working cycle of a four-stroke carburetor engine .
The third measure is an extension, or working stroke .
At the end of the compression stroke, the working mixture is ignited by an electric spark, and the mixture burns quickly. The maximum pressure during combustion reaches 30-50 kgf / cm 2 , and the temperature is 2100-2500 ° C.
The working cycle of a four-stroke carburetor engine .
Fourth measure - release
The piston moves from
n.m.t. to v.m.t., the outlet valve is open. The exhaust gases are discharged from the cylinder into the atmosphere. The release process takes place at a pressure above atmospheric. By the end of the stroke, the pressure in the cylinder decreases to 1.1-1.2 kgf / cm 2, and the temperature drops to 70O-800 ° C.
The operation of a four-stroke carburetor engine .
Split swirl combustion chamber
Forms of combustion chambers in diesel engines
Divided pre-combustion chamber
Forms of combustion chambers in diesel engines
Semi-split combustion chamber
Forms of combustion chambers in diesel engines
Unshared combustion chamber
Installation on the screen flap
Tangential channel location
Screw channel
Methods for creating a vortex motion of a charge during intake
Screw channel
Diesel engine working principle .
engine .
The operation of a two-stroke carburetor engine .
In 1799, French engineer Philippe Le Bon discovered luminaire gas and received a patent for the use and method of producing luminaire gas by dry distillation of wood or coal. This discovery was of great importance, primarily for the development of lighting technology. Very soon in France, and then in other European countries, gas lamps began to successfully compete with expensive candles. However, luminous gas was not only suitable for lighting. The inventors set about designing engines that could replace a steam engine, while the fuel would not be burned in the furnace, but directly in the engine cylinder. 1799 Philippe Lebonce French light gas Evaporation machine in the engine cylinder
In 1801, Le Bon took out a patent for the design of a gas engine. The principle of operation of this machine was based on the well-known property of the gas he discovered: its mixture with air exploded on ignition with the release of a large amount of heat. Combustion products expanded rapidly, putting strong pressure on the environment. By creating the appropriate conditions, you can use the released energy in the interests of man. The Lebon engine had two compressors and a mixing chamber. One compressor was to pump compressed air into the chamber and the other compressed luminous gas from a gas generator. The gas-air mixture then entered the working cylinder, where it ignited. The engine was double-acting, that is, alternately acting working chambers were located on both sides of the piston. Essentially, Le Bon had the idea of \u200b\u200ban internal combustion engine, but in 1804 he died before he could bring his invention to life. 1801 Le Boncompressorgas generator cylinder Lebon 1804
Jean Etienne Lenoir In the following years, several inventors from different countries tried to create a workable lamp gas engine. However, all these attempts did not lead to the appearance on the market of engines that could successfully compete with the steam engine. The honor of creating a commercially successful internal combustion engine belongs to the Belgian mechanic Jean Etienne Lenoir. While working in a galvanic plant, Lenoir came to the idea that the fuel-air mixture in a gas engine could be ignited with an electric spark, and decided to build an engine based on this idea. Jean Etienne Lenoirud's steam engine did not immediately succeed Lenoir based on this idea. After it was possible to make all the parts and assemble the car, it worked quite a bit and stopped, because due to heating, the piston expanded and jammed in the cylinder. Lenoir improved his engine by thinking over a water cooling system. However, the second start attempt also failed due to poor piston stroke. Lenoir supplemented its design with a lubrication system. Only then did the engine start running.
August Otto By 1864, more than 300 of these engines of various capacities were produced. Having become rich, Lenoir stopped working on improving his car, and this predetermined its fate, she was ousted from the market by a more perfect engine created by the German inventor August Otto. 1864 August Otto In 1864, he received a patent for his model of a gas engine and in the same year made a contract with the wealthy engineer Langen for the exploitation of this invention. Soon the company "Otto and Company" was founded. 1864 by Langen
By 1864, more than 300 of these engines of various capacities were produced. Having got rich, Lenoir stopped working on improving his car, and this predetermined her fate, she was ousted from the market by a more perfect engine created by the German inventor August Otto. 1864 August Otto In 1864, he received a patent for his model of a gas engine and in the same year made a contract with the wealthy engineer Langen for the exploitation of this invention. Otto & Company was soon formed. 1864 by Langen At first glance, the Otto engine represented a step backward from the Lenoir engine. The cylinder was vertical. The rotating shaft was placed over the cylinder from the side. A rack connected to the shaft was attached to it along the axis of the piston. The engine worked as follows. The rotating shaft lifted the piston by 1/10 of the cylinder height, as a result of which a rarefied space was formed under the piston and a mixture of air and gas was sucked in. The mixture then ignited. Neither Otto nor Langen possessed sufficient knowledge in the field of electrical engineering and abandoned electric ignition. They ignited them with an open flame through a tube. During the explosion, the pressure under the piston increased to about 4 atm. Under the action of this pressure, the piston rose, the gas volume increased and the pressure dropped. When lifting the piston, a special mechanism disconnected the rail from the shaft. The piston, first under gas pressure, and then by inertia, rose until a vacuum was created under it. Thus, the energy of the burned fuel was used in the engine with maximum efficiency. This was Otto's main original find. The downward working stroke of the piston began under the influence of atmospheric pressure, and after the pressure in the cylinder reached atmospheric, the exhaust valve was opened, and the piston displaced the exhaust gases with its mass. Due to the more complete expansion of combustion products, the efficiency of this engine was significantly higher than the efficiency of the Lenoir engine and reached 15%, that is, it exceeded the efficiency of the best steam engines of that time.
Since Otto's engines were almost five times more economical than Lenoir's engines, they immediately became in great demand. In subsequent years, about five thousand of them were produced. Otto worked hard to improve their designs. Soon the gear rack was replaced by a crank drive. But the most significant of his inventions came in 1877, when Otto took out a patent for a new four-stroke cycle engine. This cycle is at the core of most gas and petrol engines to this day. The following year, the new engines were already in production. 1877 The four-stroke cycle was Otto's greatest technical achievement. But it was soon discovered that a few years before his invention, exactly the same principle of operation of the engine had been described by the French engineer Beau de Roche. A group of French industrialists challenged Otto's patent in court. The court found their arguments convincing. Otto's rights under his patent were significantly curtailed, including the revocation of his monopoly on the four-stroke cycle.Beau de Rocha Although competitors began producing four-stroke engines, the Otto model, which had been in production for many years, was still the best, and the demand for it continued ... By 1897, about 42 thousand of these engines of various capacities were produced. However, the fact that luminous gas was used as fuel greatly narrowed the scope of the first internal combustion engines. The number of lighting and gas factories was insignificant even in Europe, while in Russia there were only two of them - in Moscow and St. Petersburg. 1897 in Europe, Russia, Moscow, St. Petersburg.
The search for a new fuel Therefore, the search for a new fuel for the internal combustion engine did not stop. Some inventors have tried to use liquid fuel vapor as a gas. Back in 1872, the American Brighton tried to use kerosene in this capacity. However, kerosene evaporated poorly, and Brighton switched to a lighter petroleum product, gasoline. But in order for a liquid fuel engine to successfully compete with a gas one, it was necessary to create a special device for evaporating gasoline and obtaining a combustible mixture of it with air. 1872 Brighton Brighton in the same 1872 invented one of the first so-called "evaporative" carburetors but he acted unsatisfactorily. Brighton 1872
Gasoline engine A workable gasoline engine did not appear until ten years later. Probably its first inventor can be called OS Kostovich, who provided a working prototype of a gasoline engine in 1880. However, his discovery is still poorly lit. In Europe, the German engineer Gottlieb Daimler made the greatest contribution to the creation of gasoline engines. For many years he worked for Otto's firm and was a member of its board. In the early 80s, he proposed to his boss a project for a compact gasoline engine that could be used in transport. Otto took Daimler's proposal coldly. Then Daimler, together with his friend Wilhelm Maybach, made a bold decision in 1882, they left the Otto company, acquired a small workshop near Stuttgart and began to work on their project. Gasoline engine Kostovich O.S. Gottlieb Daimler Daimler Wilhelm Maybach 1882
The problem facing Daimler and Maybach was not an easy one: they decided to create an engine that would not require a gas generator, would be very light and compact, but powerful enough to propel the crew. Daimler hoped to increase the power by increasing the shaft speed, but for this it was necessary to ensure the required ignition frequency of the mixture. In 1883, the first glow gasoline engine was created with ignition from a red-hot tube inserted into the cylinder of a gas generator 1883 glow-gas engine of a red-hot tube cylinder
The first model of a gasoline engine was intended for an industrial stationary installation. The evaporation process of liquid fuels in the first gasoline engines left much to be desired. Therefore, the invention of the carburetor made a real revolution in engine building. Its creator is considered to be the Hungarian engineer Donat Banki. In 1893 he took out a patent for the jet carburetor, which was the prototype of all modern carburetors. Unlike his predecessors, Banks proposed not to evaporate gasoline, but to spray it finely in the air. This ensured its uniform distribution over the cylinder, and evaporation itself took place already in the cylinder under the action of the compression heat. To ensure atomization, gasoline was sucked in by an air flow through the metering nozzle, and the consistency of the mixture composition was achieved by maintaining a constant level of gasoline in the carburetor. The jet was made in the form of one or several holes in a tube located perpendicular to the air flow. To maintain the pressure, a small reservoir with a float was provided, which maintained the level at a given height, so that the amount of gasoline drawn in was proportional to the amount of air supplied. Carburetor Donat Banks 1893 gasoline engine power, usually increased cylinder displacement. Then they began to achieve this by increasing the number of cylinders. Cylinder volume At the end of the 19th century, two-cylinder engines appeared, and from the beginning of the 20th century, four-cylinder engines began to spread.
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An internal combustion engine (ICE for short) is a device in which the chemical energy of a fuel is converted into useful mechanical work. Internal combustion engines are classified: By purpose - are divided into transport, stationary and special. By the type of fuel used - light liquid (gasoline, gas), heavy liquid (diesel fuel). According to the method of forming the combustible mixture - external (carburetor) and internal for a diesel internal combustion engine. By the way of ignition (spark or compression). According to the number and arrangement of cylinders, in-line, vertical, opposed, V-shaped, VR-shaped and W-shaped engines are divided.
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Internal combustion engine elements: Cylinder Piston - moves inside the cylinder Fuel injection valve Plug - ignites fuel inside the cylinder Gas release valve Crankshaft - is rotated by the piston
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Cycles of operation of reciprocating internal combustion engines Reciprocating internal combustion engines are classified according to the number of strokes in the working cycle into two-stroke and four-stroke. The working cycle in reciprocating internal combustion engines consists of five processes: intake, compression, combustion, expansion and exhaust.
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1. In the process of intake, the piston moves from top dead center (TDC) to bottom dead center (BDC), and the released over-piston space of the cylinder is filled with a mixture of air and fuel. Due to the pressure difference in the intake manifold and inside the engine cylinder, when the intake valve is opened, the mixture enters (is sucked) into the cylinder
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2. During the compression process, both valves are closed and the piston, moving from LMW. to v.m.t. and reducing the volume of the above-piston cavity, it compresses the working mixture (in the general case, the working fluid). Compression of the working fluid accelerates the combustion process and thus predetermines the possible full utilization of the heat released during fuel combustion in the cylinder.
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3. In the process of combustion, the fuel is oxidized by air oxygen, which is part of the working mixture, as a result of which the pressure in the above-piston cavity increases sharply.
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4. In the process of expansion, incandescent gases, striving to expand, move the piston away from the VMT. to n.m.t. The working stroke of the piston is made, which, through the connecting rod, transfers pressure to the connecting rod journal of the crankshaft and turns it.
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5. In the process of release, the piston moves from LMT. to v.m.t. and through the second valve that opens by this time, pushes the exhaust gases out of the cylinder. The combustion products remain only in the volume of the combustion chamber, from where they cannot be displaced by the piston. Continuity of engine operation is ensured by subsequent repetition of operating cycles.
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History of the automobile The history of the automobile began in 1768 with the creation of steam-powered machines capable of transporting a person. In 1806, the first cars appeared, driven by internal combustion engines. combustible gas, which led to the emergence in 1885 of the commonly used gasoline or gasoline internal combustion engine today.
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Pioneering inventors German engineer Karl Benz, the inventor of many automotive technologies, is considered the inventor of the modern automobile.
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Karl Benz In 1871, together with August Ritter, he organized a mechanical workshop in Mannheim, received a patent for a two-stroke gasoline engine, and soon patented the systems of the future car: accelerator, ignition system, carburetor, clutch, gearbox and cooling radiator.
Prepared by: Maxim Tarasov
Supervisor: Master of Industrial Training
MAOU DO MUK "Eureka"
Barakaeva Fatima Kurbanbievna
- The internal combustion engine (ICE) is one of the main devices in the design of a car, which serves to convert fuel energy into mechanical energy, which, in turn, performs useful work. The principle of operation of an internal combustion engine is based on the fact that fuel in combination with air form an air mixture. Combustion cyclically in the combustion chamber, the air-fuel mixture provides high pressure directed to the piston, which, in turn, rotates the crankshaft through the crank mechanism. Its rotational energy is transferred to the vehicle's transmission.
- A starter is often used to start an internal combustion engine — usually an electric motor that cranks the crankshaft. In heavier diesel engines, an auxiliary ICE ("launcher") is used as a starter and for the same purpose.
- There are the following types of engines (ICE):
- petrol
- diesel
- gas
- gas-diesel
- rotary piston
- Gasoline internal combustion engines - the most common of automobile engines. Gasoline serves as fuel for them. Passing through the fuel system, gasoline enters the carburetor or intake manifold through the spray nozzles, and then this air-fuel mixture is fed into the cylinders, compressed under the influence of the piston group, and ignited by the spark from the spark plugs.
- The carburetor system is considered obsolete, so the fuel injection system is now widely used. Fuel atomizing nozzles (injectors) inject either directly into the cylinder or into the intake manifold. Injection systems are divided into mechanical and electronic. Firstly, plunger-type mechanical lever mechanisms are used for fuel metering, with the possibility of electronic control of the fuel mixture. Secondly, the process of drawing up and injection of fuel is completely assigned to the electronic control unit (ECU). Injection systems are necessary for more thorough fuel combustion and minimization of harmful combustion products.
- Diesel internal combustion engines use special diesel fuel ... Engines of this type of car do not have an ignition system: the fuel mixture entering the cylinders through the injectors is capable of exploding under the influence of high pressure and temperature, which are provided by the piston group.
Gasoline and diesel engines. Gasoline and Diesel Duty Cycles
- use gas as a fuel - liquefied, generator, compressed natural. The proliferation of such engines was due to the growing requirements for environmental safety of transport. The original fuel is stored in cylinders under high pressure, from where it enters the gas reducer through the evaporator, losing pressure. Further, the process is similar to an injection gasoline internal combustion engine. In some cases, gas supply systems may not use vaporizers.
- A modern car is most often driven by an internal combustion engine. There are many such engines. They differ in volume, number of cylinders, power, rotational speed, fuel used (diesel, gasoline and gas internal combustion engines). But, in principle, the device of the internal combustion engine seems to be.
- How does an engine work and why is it called a four-stroke internal combustion engine? Internal combustion is clear. Fuel burns inside the engine. Why 4 engine strokes, what is it? Indeed, there are also two-stroke engines. But they are rarely used on cars.
- The four-stroke engine is called due to the fact that its work can be divided into four, equal in time, parts. The piston will move four times through the cylinder - two times up and two times down. The stroke begins when the piston is at its extreme low or high point. For motorists, mechanics call this top dead center (TDC) and bottom dead center (BDC).
- The first stroke, also known as intake, starts at TDC (top dead center). Moving down, the piston sucks the air-fuel mixture into the cylinder. The operation of this stroke occurs when the intake valve is open. By the way, there are many engines with multiple intake valves. Their number, size, time in the open state can significantly affect the engine power. There are engines in which, depending on pressing the gas pedal, there is a forced increase in the time that the intake valves are open. This is done to increase the amount of sucked in fuel, which, after ignition, increases engine power. The car, in this case, can accelerate much faster.
- The next stroke of the engine is the compression stroke. After the piston has reached its lowest point, it begins to rise upward, thereby compressing the mixture that entered the cylinder at the intake stroke. The fuel mixture is compressed to the volume of the combustion chamber. What is this camera? The free space between the top of the piston and the top of the cylinder when the piston is at top dead center is called the combustion chamber. The valves are completely closed during this stroke of the engine. The tighter they are closed, the better the compression is. In this case, the condition of the piston, cylinder, piston rings is of great importance. If there are large gaps, then good compression will not work, and accordingly, the power of such an engine will be much lower. Compression can be checked with a special device. By the amount of compression, one can conclude about the degree of engine wear.
- The third cycle is a working one, it starts from TDC. It is no coincidence that he is called a worker. After all, it is in this beat that the action takes place that makes the car move. In this cycle, the ignition system comes into operation. Why is this system called that? Yes, because it is responsible for igniting the fuel mixture compressed in the cylinder in the combustion chamber. It works very simply - the candle of the system gives a spark. In fairness, it is worth noting that the spark is emitted from the spark plug a few degrees before the piston reaches the top point. These degrees, in a modern engine, are automatically regulated by the "brains" of the car.
- After the fuel ignites, an explosion occurs - it sharply increases in volume, forcing the piston to move downward. The valves in this stroke of the engine, as in the previous one, are in a closed state.
Fourth measure - release measure
- The fourth stroke of the engine, the last one is exhaust. Having reached the bottom point, after the working stroke, the exhaust valve in the engine begins to open. There may be several such valves, as well as intake valves. Moving up, the piston removes the exhaust gases from the cylinder through this valve - ventilates it. The precise operation of the valves determines the degree of compression in the cylinders, the complete removal of exhaust gases and the required amount of sucked-in fuel-air mixture.
- After the fourth measure, it is the turn of the first. The process is repeated cyclically. And due to what does the rotation take place - the operation of the internal combustion engine all 4 strokes, which makes the piston rise and fall in the compression, exhaust and intake strokes? The fact is that not all of the energy received in the working stroke is directed to the movement of the car. Part of the energy is spent on unwinding the flywheel. And he, under the influence of inertia, turns the crankshaft of the engine, moving the piston during the "non-working" strokes.
The presentation was prepared based on materials from the site http://autoustroistvo.ru
Description of the presentation by individual slides:
1 slide
Slide Description:
Car engine Prepared by: Tarasov Maxim Yurievich 11th grade Supervisor: Master of industrial training MAOU DO MUK "Eureka" Barakaeva Fatima Kurbanbievna
2 slide
Slide Description:
3 slide
Slide Description:
Car engine The internal combustion engine (ICE) is one of the main devices in the construction of a car, which serves to convert fuel energy into mechanical energy, which, in turn, performs useful work. The principle of operation of an internal combustion engine is based on the fact that fuel in combination with air form an air mixture. Combustion cyclically in the combustion chamber, the air-fuel mixture provides high pressure directed to the piston, which, in turn, rotates the crankshaft through the crank mechanism. Its rotational energy is transferred to the vehicle's transmission. A starter is often used to start an internal combustion engine - usually an electric motor that cranks the crankshaft. In heavier diesel engines, an auxiliary ICE ("launcher") is used as a starter and for the same purpose.
4 slide
Slide Description:
Types of engines There are the following types of engines (ICE): gasoline diesel gas gas diesel rotary piston
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Slide Description:
Internal combustion engines are also classified: by the type of fuel, by the number and arrangement of cylinders, by the method of forming the fuel mixture, by the number of strokes of the internal combustion engine, etc.
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Slide Description:
Gasoline and diesel engines. Gasoline and Diesel Engine Duty Cycles Gasoline internal combustion engines are the most common automotive engines. Gasoline serves as fuel for them. Passing through the fuel system, gasoline enters the carburetor or intake manifold through the spray nozzles, and then this air-fuel mixture is fed into the cylinders, compressed under the influence of the piston group, and ignited by the spark from the spark plugs. The carburetor system is considered obsolete, so the fuel injection system is now widely used. Fuel atomizing nozzles (injectors) inject either directly into the cylinder or into the intake manifold. Injection systems are divided into mechanical and electronic. Firstly, plunger-type mechanical lever mechanisms are used for fuel metering, with the possibility of electronic control of the fuel mixture. Secondly, the process of drawing up and injection of fuel is completely assigned to the electronic control unit (ECU). Injection systems are necessary for more thorough fuel combustion and minimization of harmful combustion products. Diesel internal combustion engines use special diesel fuel. Engines of this type of car do not have an ignition system: the fuel mixture entering the cylinders through the injectors is capable of exploding under the influence of high pressure and temperature, which are provided by the piston group.
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Slide Description:
Gas engines Gas engines use gas as fuel - liquefied, generator, compressed natural gas. The proliferation of such engines was due to the growing requirements for environmental safety of transport. The original fuel is stored in cylinders under high pressure, from where it enters the gas reducer through the evaporator, losing pressure. Further, the process is similar to an injection gasoline internal combustion engine. In some cases, gas supply systems may not use vaporizers.
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Slide Description:
How the Internal Combustion Engine Works A modern car is most often driven by an internal combustion engine. There are many such engines. They differ in volume, number of cylinders, power, rotational speed, fuel used (diesel, gasoline and gas internal combustion engines). But, in principle, the device of the internal combustion engine seems to be. How does an engine work and why is it called a four-stroke internal combustion engine? Internal combustion is clear. Fuel burns inside the engine. Why 4 engine strokes, what is it? Indeed, there are also two-stroke engines. But they are rarely used on cars. The four-stroke engine is called due to the fact that its work can be divided into four, equal in time, parts. The piston will move four times through the cylinder - two times up and two times down. The stroke begins when the piston is at its extreme low or high point. For motorists-mechanics this is called top dead center (TDC) and bottom dead center (BDC).
9 slide
Slide Description:
First stroke - intake stroke The first stroke, also known as intake stroke, starts from TDC (top dead center). Moving down, the piston sucks the air-fuel mixture into the cylinder. The operation of this stroke occurs when the intake valve is open. By the way, there are many engines with multiple intake valves. Their number, size, time in the open state can significantly affect the engine power. There are engines in which, depending on pressing the gas pedal, there is a forced increase in the time that the intake valves are open. This is done to increase the amount of sucked in fuel, which, after ignition, increases engine power. The car, in this case, can accelerate much faster.
10 slide
Slide Description:
Second stroke - compression stroke The next engine stroke - compression stroke. After the piston reaches the bottom point, it begins to rise upward, thereby compressing the mixture that entered the cylinder in the intake stroke. The fuel mixture is compressed to the volume of the combustion chamber. What is this camera? The free space between the top of the piston and the top of the cylinder when the piston is at top dead center is called the combustion chamber. The valves are completely closed at this stroke of the engine. The tighter they are closed, the better the compression is. Of great importance, in this case, is the condition of the piston, cylinder, piston rings. If there are large gaps, then good compression will not work, and accordingly, the power of such an engine will be much lower. Compression can be checked with a special device. By the amount of compression, one can conclude about the degree of engine wear.
11 slide
Slide Description:
The third cycle - working stroke The third cycle - working, starts from TDC. It is no coincidence that he is called a worker. After all, it is in this beat that the action takes place that makes the car move. In this cycle, the ignition system comes into operation. Why is this system called that? Yes, because it is responsible for igniting the fuel mixture compressed in the cylinder in the combustion chamber. It works very simply - the candle of the system gives a spark. In fairness, it is worth noting that the spark is emitted from the spark plug a few degrees before the piston reaches the top point. These degrees, in a modern engine, are automatically regulated by the "brains" of the car. After the fuel ignites, an explosion occurs - it sharply increases in volume, forcing the piston to move downward. The valves in this stroke of the engine, as in the previous one, are in a closed state.
12 slide
Slide Description:
The fourth stroke is the exhaust stroke The fourth stroke of the engine, the last one is the exhaust stroke. Having reached the bottom point, after the working stroke, the exhaust valve in the engine begins to open. There may be several such valves, as well as intake valves. Moving upward, the piston removes the exhaust gases from the cylinder through this valve - ventilates it. The precise operation of the valves determines the degree of compression in the cylinders, the complete removal of exhaust gases and the required amount of sucked-in fuel-air mixture. After the fourth measure, it is the turn of the first. The process is repeated cyclically. And due to what does the rotation take place - the operation of the internal combustion engine all 4 strokes, which makes the piston rise and fall in the compression, exhaust and intake strokes? The fact is that not all of the energy received in the working stroke is directed to the movement of the car. Part of the energy is spent on unwinding the flywheel. And he, under the influence of inertia, turns the crankshaft of the engine, moving the piston during the "non-working" strokes. The presentation was prepared based on materials from the site http://autoustroistvo.ru
