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August Otto In 1864, more than 300 of these engines of various capacities were produced. Having grown rich, Lenoir stopped working on improving his car, and this predetermined her fate - she was forced out of the market by a more advanced engine created by the German inventor August Otto. In 1864, he received a patent for his model of a gas engine and in the same year entered into an agreement with the wealthy engineer Langen to exploit this invention. Soon the firm "Otto and Company" was created. At first glance, the Otto engine represented a step backwards from the Lenoir engine. The cylinder was vertical. The rotating shaft was placed above the cylinder on the side. Along the axis of the piston, a rail connected to the shaft was attached to it. The engine worked as follows. The rotating shaft raised the piston by 1/10 of the height of the cylinder, as a result of which a rarefied space formed under the piston and a mixture of air and gas was sucked in. The mixture then ignited. Neither Otto nor Langen had sufficient knowledge of electrical engineering and abandoned electric ignition. They ignited with an open flame through a tube. During the explosion, the pressure under the piston increased to approximately 4 atm. Under the action of this pressure, the piston rose, the volume of gas increased and the pressure fell. When the piston was raised, 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 burnt fuel was used in the engine with maximum completeness. 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 pressure, the exhaust valve opened, and the piston displaced the exhaust gases with its mass. Due to the more complete expansion of the combustion products, the efficiency of this engine was significantly higher than Engine efficiency Lenoir and reached 15%, that is, it exceeded the efficiency of the best steam engines that time.
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The search for new fuel Therefore, the search for new fuel for the engine did not stop internal combustion. Some inventors have tried to use liquid fuel vapor as gas. Back in 1872, the American Brighton tried to use kerosene in this capacity. However, kerosene did not evaporate well, and Brighton switched to a lighter petroleum product - gasoline. But in order for a liquid fuel engine to successfully compete with a gas engine, it was necessary to create special device for the evaporation of gasoline and obtaining combustible mixture him with air. Brighton in the same 1872 invented one of the first so-called "evaporative" carburetors, but he did not work satisfactorily.
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1860 Étienne Lenoir invents the first engine powered by lighting gas Étienne Lenoir (1822-1900) Stages in the development of internal combustion engines: 1862 Alphonse Beau De Rochas proposed the idea of a four-stroke engine. However, he failed to implement his idea. 1876 Nikolaus August Otto creates the Roche four-stroke engine. 1883 Daimler proposed the design of an engine that could run on both gas and gasoline. By 1920, internal combustion engines become leading. crews on steam and electric traction have become a rarity. Karl Benz invented the self-propelled tricycle based on Daimler technology. August Otto (1832-1891) Daimler Karl Benz
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Duty cycle of a four-stroke carburetor engine internal combustion takes place in 4 strokes of the piston (stroke), i.e., in 2 revolutions of the crankshaft. Four-stroke engine 1 stroke - intake (the combustible mixture from the carburetor enters the cylinder) There are 4 strokes: 2 stroke - compression (the valves are closed and the mixture is compressed, at the end of compression the mixture is ignited by an electric spark and fuel is burned) 3 stroke - working stroke (conversion occurs heat received from fuel combustion into mechanical work) 4 stroke - exhaust (exhaust gases are displaced by the piston)
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In practice, the power of a two-stroke carburetor internal combustion engine often not only does not exceed the power of a four-stroke, but is even lower. This is due to the fact that a significant part of the stroke (20-35%) the piston makes with open valves Two-stroke engine There is also a two-stroke internal combustion engine. The working cycle of a two-stroke carburetor internal combustion engine is carried out in two strokes of the piston or in one revolution of the crankshaft. Compression Combustion exhaust intake 1 stroke 2 stroke
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Ways to increase engine power: The efficiency of an internal combustion engine is low and is approximately 25% - 40%. The maximum effective efficiency of the most advanced internal combustion engines is about 44%. Therefore, many scientists are trying to increase the efficiency, as well as the engine power itself. Use of multi-cylinder engines Use of special fuel (correct mixture ratio and type of mixture) Replacement of engine parts ( correct sizes constituent parts, depending on the type of engine) Elimination of part of the heat loss by transferring the place of fuel combustion and heating the working fluid inside the cylinder
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One of the most important characteristics of an engine is its compression ratio, which is defined as follows: Compression ratio e V2 V1 where V2 and V1 are the volumes at the start and end of compression. With an increase in the compression ratio, the initial temperature of the combustible mixture at the end of the compression stroke increases, which contributes to its more complete combustion.
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liquid gas with spark ignition without spark ignition (diesel) (carburetor)
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The structure of a prominent representative of the internal combustion engine - a carburetor engine Engine skeleton (crankcase, cylinder heads, crankshaft bearing caps, oil pan) Movement mechanism (pistons, connecting rods, crankshaft, flywheel) Gas distribution mechanism (camshaft, pushers, rods, rocker arms) Lubrication system (oil, coarse filter, sump) liquid (radiator, liquid, etc.) Air cooling system (blowing with air flows) Power system ( fuel tank, fuel filter, carburetor, pumps)
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The structure of a prominent representative of the internal combustion engine - a carburetor engine Ignition system (power source - generator and battery, chopper + capacitor) Starting system (electric starter, current source - battery, elements remote control) Intake and exhaust system (pipelines, air filter, muffler) Engine carburetor
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Principle of operation The principle of operation of the internal combustion engine was based on the pistol invented by Alessandro Volta in 1777. This principle consisted in the fact that instead of gunpowder, a mixture of air and coal gas was ignited with the help of an electric spark. In 1807, the Swiss Isaac de Rivatz received a patent for the use of a mixture of air and coal gas as a means of generating mechanical energy. Its engine was built into the car, consisting of a cylinder in which, due to the explosion, the piston moved up, and when moving down, it actuated a swing arm. In 1825, Michael Faraday obtained benzene from coal, the first liquid fuel for an internal combustion engine. Until 1830, many Vehicle, which did not yet have true internal combustion engines, but had engines that used a mixture of air and coal gas instead of steam. It turned out that this solution did not bring great advantages, moreover, the production of such engines was unsafe. The foundation for a light, compact engine was laid only in 1841 by the Italian Luigi Christophoris, who built an engine that worked on the principle of "compression-ignition". Such an engine had a pump that supplied a flammable liquid - kerosene - as fuel. Until 1830, many vehicles were produced that did not yet have true internal combustion engines, but had engines that used a mixture of air and coal gas instead of steam. It turned out that this solution did not bring great advantages, moreover, the production of such engines was unsafe.
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The appearance of the first internal combustion engines The foundation for the creation of a light, compact engine was laid only in 1841 by the Italian Luigi Cristoforis, who built an engine operating on the "compression-ignition" principle. Such an engine had a pump that supplied a flammable liquid - kerosene - as fuel. Eugenio Barzanti and Fetis Mattocci developed this idea and in 1854 introduced the first true internal combustion engine. It ran in a three-stroke sequence (no compression stroke) and was water-cooled. Although other types of fuel were also considered, they nevertheless chose a mixture of air and coal gas as a fuel and at the same time reached a power of 5 hp. In 1858, another two-cylinder engine appeared - with opposite cylinders. By then the Frenchman Etienne Lenoir had completed the project begun by his compatriot Hugon in 1858. In 1860, Lenoir patented his own internal combustion engine, which was later a great commercial success. The engine ran on coal gas in a three-stroke mode. In 1863, they tried to install it on a car, but the power of 1.5 hp. at 100 rpm was not enough to move. At the World Exhibition in Paris in 1867, the Deutz gas engine factory, founded by engineer Nicholas Otto and industrialist Eugen Langen, presented an engine based on the Barzanti-Mattocci principle. It was lighter, created less vibration and soon took the place of the Lenoir engine. A real revolution in the development of the internal combustion engine occurred with the introduction of a four-stroke engine, patented by the Frenchman Alphonse Bea de Rocha in 1862 and finally replacing the Otto engine from service by 1876.
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Wankel engine Rotary piston engine internal combustion engine (Wankel engine), the design of which was developed in 1957 by engineer Felix Wankel (F. Wankel, Germany). A feature of the engine is the use of a rotating rotor (piston) placed inside the cylinder, the surface of which is made according to the epitrochoid. The rotor mounted on the shaft is rigidly connected to the gear wheel, which engages with the fixed gear. A rotor with a gear wheel, as it were, rolls around the gear. At the same time, its edges slide along the epitrochoidal surface of the cylinder and cut off the variable volumes of the chambers in the cylinder. This design allows a 4-stroke cycle to be carried out without the use of a special gas distribution mechanism.
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Jet engine Gradually, year after year, the speed of transport vehicles increased and more and more powerful heat engines were required. The more powerful such an engine, the larger its size. A large and heavy engine could be placed on a ship or on a diesel locomotive, but it was no longer suitable for an aircraft, the weight of which is limited. Then, instead of piston engines, aircraft began to install jet engines, which, despite their small size, could develop enormous power. Even more powerful, more powerful jet engines are supplied with rockets, with the help of which spaceships, artificial satellites of the Earth and interplanetary spacecraft take off into the sky. At a jet engine, a jet of fuel burning in it flies out of a pipe (nozzle) at great speed and pushes an airplane or rocket. The speed of a space rocket, on which such engines are installed, can exceed 10 km per second!
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So, we see that internal combustion engines are a very complex mechanism. And the function performed by thermal expansion in internal combustion engines is not as simple as it seems at first glance. And there would be no internal combustion engines without the use of thermal expansion of gases. And we are easily convinced of this by examining in detail the principle of operation of internal combustion engines, their operating cycles - all their work is based on the use of thermal expansion of gases. But ICE is only one of the specific applications of thermal expansion. And judging by the benefits that thermal expansion brings to people through an internal combustion engine, one can judge the benefits of this phenomenon in other areas of human activity. And let the era of the internal combustion engine pass, let them have many shortcomings, let new engines appear that do not pollute the internal environment and do not use the thermal expansion function, but the first ones will benefit people for a long time, and people in many hundreds of years will respond kindly about them, because they brought humanity to a new level of development, and having passed it, humanity rose even higher.
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Physics lesson in grade 8
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Question 1:
What physical quantity shows how much energy is released when burning 1 kg of fuel? What letter is it? Specific heat of combustion of fuel. g
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Question 2:
Determine the amount of heat released during the combustion of 200 g of gasoline. g=4.6*10 7J/kg Q=9.2*10 6J
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Question 3:
The specific heat of combustion of coal is about 2 times greater than the specific heat of combustion of peat. What does it mean. This means that the combustion of coal will require 2 times more heat.
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Internal combustion engine
All bodies have internal energy - earth, bricks, clouds and so on. However, most often it is difficult to extract it, and sometimes impossible. The most easily used for human needs is the internal energy of only some, figuratively speaking, "combustible" and "hot" bodies. These include: oil, coal, warm springs near volcanoes, and so on. Consider one of the examples of using the internal energy of such bodies.
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Carburetor engine.
carburetor - a device for mixing gasoline with air in the right proportions.
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Main main parts of an internal combustion engine parts of an internal combustion engine
1 - intake air filter, 2 - carburetor, 3 - gas tank, 4 - fuel line, 5 - spray gasoline, 6 - intake valve, 7 - glow plug, 8 - combustion chamber, 9 - exhaust valve, 10 - cylinder, 11 - piston.
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The main parts of the internal combustion engine:
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The operation of this engine consists of several stages repeating one after another, or, as they say, cycles. There are four in total. The stroke count starts from the moment when the piston is at its highest point, and both valves are closed.
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The first stroke is called the inlet (Fig. "a"). The intake valve opens and the descending piston draws the gasoline-air mixture into the combustion chamber. The intake valve then closes.
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The second step is compression (Fig. "b"). The piston, rising up, compresses the gasoline-air mixture.
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The third stroke is the working stroke of the piston (Fig. "c"). An electric spark flashes at the end of the candle. The gasoline-air mixture burns almost instantly and there is a heat. This leads to a strong increase in pressure and the hot gas does useful work - it pushes the piston down.
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The fourth measure is the release (rice "d"). The exhaust valve opens and the piston, moving up, pushes the gases out of the combustion chamber into exhaust pipe. Then the valve closes.
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physical education minute
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Diesel engine.
In 1892, the German engineer R. Diesel received a patent (a document confirming the invention) for an engine, later named after him.
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Principle of operation:
Only air enters the cylinders of a Diesel engine. The piston, compressing this air, does work on it and the internal energy of the air increases so much that the fuel injected there immediately ignites spontaneously. The resulting gases push the piston back, carrying out the working stroke.
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Work cycles:
air intake; air compression; fuel injection and combustion - piston stroke; release of exhaust gases. A significant difference: the glow plug becomes unnecessary, and its place is taken by a nozzle - a device for injecting fuel; usually these are low-quality grades of gasoline.
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Some information about engines Engine type Engine type
Some information about engines Carburetor Diesel
History of creation First patented in 1860 by the Frenchman Lenoir; in 1878 built by German. inventor Otto and engineer Langen Invented in 1893 by German engineer Diesel
Working fluid Air, sat. gasoline vapor Air
Fuel Gasoline Fuel oil, oil
Max. chamber pressure 6 × 105 Pa 1.5 × 106 - 3.5 × 106 Pa
T at compression of the working fluid 360-400 ºС 500-700 ºС
T of fuel combustion products 1800 ºС 1900 ºС
Efficiency: for serial machines for the best samples 20-25% 35% 30-38% 45%
Application In cars of relatively small power In heavier machines of high power (tractors, freight tractors, diesel locomotives).
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Name the main parts of the engine:
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1. What are the main cycles of the internal combustion engine. 2. In what cycles are the valves closed? 3. In what cycles is valve 1 open? 4. In what cycles is valve 2 open? 5. What is the difference between an internal combustion engine and a diesel engine?
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Dead spots - extreme positions of the piston in the cylinder
Piston stroke - the distance traveled by the piston from one dead center to another
Four-stroke engine - one working cycle occurs in four piston strokes (4 cycles).
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Fill in the table
Bar name Piston movement 1 valve 2 valve What happens
Inlet
Compression
working stroke
release
down
up
down
up
open
open
closed
closed
closed
closed
closed
closed
Combustible mixture suction
Compression of the combustible mixture and ignition
The gases push the piston
Exhaust gas emission
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1. Type heat engine, in which steam rotates the engine shaft without the help of a piston, connecting rod and crankshaft. 2. Designation of specific heat of fusion. 3. One of the parts of the internal combustion engine. 4. Cycle cycle of an internal combustion engine. 5. The transition of a substance from a liquid to a solid state. 6. Vaporization occurring from the surface of the liquid.
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Car engine Prepared by: Tarasov Maxim Yuryevich Grade 11 Supervisor: master of industrial training MAOU DO MUK "Evrika" Barakaeva Fatima Kurbanbievna
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Car engine An 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. Cyclically burning 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 Electrical engine turning the crankshaft. In heavier diesel engines, an auxiliary internal combustion engine (“starter”) is used as a starter and for the same purpose.
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Types of engines There are the following types of engines (ICE): gasoline diesel gas gas-diesel rotary piston
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Also, internal combustion engines are classified: by type of fuel, by the number and arrangement of cylinders, by the method of forming the fuel mixture, by the number of cycles of the internal combustion engine, etc.
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Petrol and diesel engines. Gasoline and diesel engine operating cycles Gasoline engines internal combustion are the most common automotive engines. Their fuel is gasoline. passing through fuel system, gasoline enters the carburetor or intake manifold through spray nozzles, and then this air-fuel mixture is supplied to the cylinders, compressed under the influence of the piston group, and ignited by a spark from 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 divided into mechanical and electronic. Firstly, mechanical lever mechanisms of the plunger type are used for fuel dosing, with the possibility of electronic control of the fuel mixture. Secondly, the process of compiling and injecting fuel is completely entrusted to the electronic unit control (ECU). Injection systems are necessary for more thorough combustion of fuel and minimization of harmful combustion products. Diesel internal combustion engines use special diesel fuel. Car engines of this type do not have an ignition system: the fuel mixture entering the cylinders through the nozzles can explode under the high pressure and temperature provided by the piston group.
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gas engines Gas engines use gas as fuel - liquefied, generator, compressed natural. The spread of such engines was due to the growing requirements for the environmental safety of transport. The initial 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 injection gasoline ICE. In some cases, gas supply systems may not include evaporators.
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The principle of operation of the internal combustion engine modern car, most often driven by an internal combustion engine. There are many such engines. They differ in volume, number of cylinders, power, rotation speed, fuel used (diesel, gasoline and gas internal combustion engines). But, in principle, the device of the internal combustion engine, it seems. How does an engine work and why is it called a four-stroke internal combustion engine? I understand about internal combustion. Fuel burns inside the engine. And why 4 cycles of the engine, what is it? Indeed, there are two-stroke engines. But on cars they are used extremely rarely. A four-stroke engine is called because its work can be divided into four parts equal in time. The piston will pass through the cylinder four times - twice up and twice down. The stroke begins when the piston is at its lowest or highest point. For motorists-mechanics, this is called top dead center (TDC) and bottom dead center (BDC).
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The first stroke - the intake stroke The first stroke, also known as the intake stroke, starts at TDC (top dead center). As the piston moves down, it draws the air-fuel mixture into the cylinder. The operation of this stroke occurs with the intake valve open. By the way, there are many engines with multiple intake valves. Their number, size, time spent in the open state can significantly affect engine power. There are engines in which, depending on the pressure on the gas pedal, there is a forced increase in the time the intake valves are open. This is done to increase the amount of fuel taken in, which, once ignited, increases engine power. The car, in this case, can accelerate much faster.
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The second stroke is the compression stroke The next stroke of the engine is the compression stroke. After the piston reaches its lowest point, it begins to rise, thereby compressing the mixture that entered the cylinder on the intake stroke. The fuel mixture is compressed to the volume of the combustion chamber. What kind of camera is this? 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. Of great importance, in this case, 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 magnitude of the compression, one can draw a conclusion about the degree of engine wear.
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The third stroke - the working stroke The third stroke is the working one, it starts from TDC. It is called a worker for a reason. After all, it is in this cycle that an action occurs that makes the car move. At this point, the ignition system comes into play. Why is this system so called? 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 given out on the spark plug a few degrees before the piston reaches the top point. These degrees are 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 down. The valves in this stroke of the engine, as in the previous one, are in the closed state.
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The fourth stroke - 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 begins to open in the engine. There may be several such valves, as well as intake valves. Moving up, the piston removes exhaust gases from the cylinder through this valve - it ventilates it. The degree of compression in the cylinders, the complete removal of exhaust gases and the required amount of intake air depend on the precise operation of the valves. 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 occur - the operation of the internal combustion engine all 4 strokes, which causes the piston to rise and fall in the compression, exhaust and intake strokes? The fact is that not all the energy received in the working cycle is directed to the movement of the car. Part of the energy is used to spin the flywheel. And he, under the influence of inertia, turns the crankshaft of the engine, moving the piston during the period of "non-working" cycles. The presentation was prepared based on the materials of the site http://autoustroistvo.ru