Presentation for the work history of internal combustion engines. Presentation on the topic "internal combustion engines"

In 1799, French engineer Philippe Lebon discovered lighting gas and received a patent for the use and method of obtaining lighting 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, lighting gas was suitable not only for lighting. The inventors set about designing engines that could replace a steam engine, while the fuel would not burn in the furnace, but directly in the engine cylinder.

In 1801, Le Bon took out a patent for the design 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 when ignited, releasing a large amount of heat. The products of combustion rapidly expanded, exerting strong pressure on the environment. By creating the appropriate conditions, it is possible to use the released energy in the interests of man. The Lebon engine had two compressors and a mixing chamber. One compressor was supposed to pump compressed air into the chamber, and the other compressed light gas from the gas generator. The gas-air mixture then entered the working cylinder, where it ignited. The engine was double-acting, that is, the working chambers were alternately acting on both sides of the piston. Essentially, Lebon nurtured the idea of an engine internal combustion, however, in 1804 he died without having time to bring his invention to life. 1801 Lebon compressor gas generator cylinder Lebon 1804

Jean Etienne Lenoir In the following years, several inventors from different countries tried to create a workable engine using light gas. 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 at an electroplating plant, Lenoir came up with the idea that the air-fuel mixture in a gas engine could be ignited with an electric spark, and decided to build an engine based on this idea. With a steam engine to Jean Etienne Lenoir, an engine based on this idea Lenoir did not immediately succeed. After it was possible to make all the parts and assemble the machine, it worked for 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 launch attempt also ended in failure due to poor piston stroke. Lenoir supplemented his 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 had already been 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. 1864 August Otto In 1864, he received a patent for his gas engine model and in the same year entered into an agreement with the wealthy engineer Langen to exploit this invention. Soon the company "Otto and Company" was created. In 1864, Langen

By 1864, more than 300 of these engines of various capacities had already been 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. 1864 August Otto In 1864, he received a patent for his gas engine model and in the same year entered into an agreement with the wealthy engineer Langen to exploit this invention. Otto and Company was soon established. 1864 by Langen 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 action 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. engine Otto

Since Otto engines were almost five times more efficient than Lenoir engines, they were immediately in high demand. In subsequent years, about five thousand of them were produced. Otto worked hard to improve their design. Soon the gear rack was replaced by a crank gear. But the most significant of his inventions came in 1877, when Otto took out a patent for new engine with a four stroke cycle. This cycle still underlies the operation of most gas and gasoline engines to this day. The following year, new engines were already in production. 1877 The four-stroke cycle was the largest technical achievement Otto. But it soon turned out that a few years before his invention, exactly the same principle of operation of the engine was described by the French engineer Beau de Rocha. A group of French industrialists challenged Otto's patent in court. The court considered their arguments persuasive. Otto's rights arising from his patent were significantly reduced, including his monopoly on the four-stroke cycle was annulled. Bo de Rocha Although competitors launched the production of four-stroke engines, Otto's model worked out over many years of production was still the best, and demand for it did not stop . By 1897, about 42 thousand of these engines of various capacities were produced. However, the fact that light gas was used as fuel greatly narrowed the scope of the first internal combustion engines. The number of lighting and gas plants was insignificant even in Europe, and in Russia there were only two of them - in Moscow and 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 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 to evaporate gasoline and obtain a combustible mixture of it with air. 1872 Brighton Brighton in the same 1872 came up with 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, Kostovich O.S., who provided a working prototype of a gasoline engine in 1880, can be called its first inventor. However, his discovery still remains poorly lit. In Europe, the German engineer Gottlieb Daimler made the greatest contribution to the creation of gasoline engines. For many years he worked in the firm Otto 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 reacted coldly to Daimler's proposal. 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 working on their project.

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 at the same time powerful enough to move the crew. Daimler expected to increase 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 incandescent gasoline engine was created with ignition from a hot tube inserted into the cylinder of a gas generator. 1883 an incandescent gasoline engine of a hot tube

The first model of a gasoline engine was intended for an industrial stationary installation. The process of evaporation of liquid fuel 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 the Hungarian engineer Donat Banki. In 1893, he took out a patent for a jet carburetor, which was the prototype of all modern carburetors. Unlike his predecessors, Banki proposed not to evaporate gasoline, but to finely spray it into the air. This ensured its uniform distribution over the cylinder, and the evaporation itself took place already in the cylinder under the action of compression heat. To ensure spraying, gasoline was sucked in by an air flow through a metering jet, and the constancy of the mixture was achieved by maintaining a constant level of gasoline in the carburetor. The jet was made in the form of one or more holes in the tube, located perpendicular to the air flow. To maintain the pressure, a small tank was provided with a float that maintained the level at a given height, so that the amount of gasoline sucked in was proportional to the amount of incoming air. engine power, usually increased the volume of the cylinder. 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.XIX centuryXX

BPOU Russian-Polyansk Agricultural College

Presentation for the lesson
on the topic: 1.2 "Internal combustion engines"
On the subject Operation and maintenance of tractors
1st year student, specialty – Tractor driver of agricultural production
Developed by - teacher of special disciplines
Goryacheva Ludmila Borisovna
Russian Polyana - 2015

INTERNAL COMBUSTION ENGINES

Internal combustion engines are heat engines, in which the chemical energy of the fuel burning inside the working cavity of the engine is converted into mechanical work.
Internal combustion engines are divided into two groups: diesel engines with compression ignition, running on diesel fuel, and carburettor engines with positive ignition, running on gasoline, and to start them - carburettor engines.
The diesel internal combustion engine consists of the main components: a crankcase, a connecting rod-crank mechanism, a gas distribution mechanism, a power supply system, fuel equipment and a regulator, a lubrication system, a cooling system, starting device.

ICE classification

Internal combustion engines are divided into two main groups: diesel engines and carburetor engines.
Diesel engines (diesels) are used as the main power plants to create traction base machine, moving it, hydraulic drive mounted and trailed implements, as well as auxiliary purposes (brake control, steering, electric lighting).
Carburetor engines on tractors are used to start the main engine.
Distinctive features of diesel engines include simplicity of design and reliability in operation, efficiency, ease of start-up and control, reliability of start-up in summer and in cold climates, stability of operation. Compared to carburetor engines, diesel engines provide greater efficiency from 25 to 32%, lower fuel consumption from 25 to 30%, low cost operation due to the lower price of heavy fuel, simpler in design due to the absence of an ignition system
Internal combustion engines mounted on tractors are called autotractor.

ICE classification

By appointment
The main engines are constantly running during the execution of work cycles, the movement of tractors from one object to another, and the performance of auxiliary operations.
Starting motors are switched on only at the moment of starting the main motor.
By type and method of ignition of combustible mixtures
Diesel engines operate on the ignition of fuel in air. The combustible mixture is ignited by increasing the temperature of the air during compression in the cylinders and spraying the fuel with nozzles.
Carburetor engines run on a combustible mixture, which is prepared in a carburetor and ignited in the cylinders with an electric spark.
By type of fuel burned
Distinguish between internal combustion engines that run on heavy liquid fuels (for example, diesel, kerosene) and those that run on light fuels (gasoline with various octane numbers) and gaseous (butane propane).

According to the method of formation of a combustible mixture
With internal mixture formation carried out in diesel engines, the air is sucked in separately and saturated with atomized diesel fuel inside the cylinders before ignition.
With external mixture formation, they are used for gasoline and gas fuels. The air sucked in by the engine is mixed with gasoline or gas in a carburetor or mixer until the combustible mixture enters the cylinders.

Operating cycle of a four-stroke four-cylinder diesel engine Intake stroke.

With the help of an external source of energy, for example electric motor(electric starter), rotate the crankshaft of the diesel engine and its piston begins to move from the T.M.T. to n.m.t. (Fig. 1, a). The volume above the piston increases, as a result of which the pressure drops to 75 ... 90 kPa. Simultaneously with the beginning of the piston movement, the valve opens the inlet channel, through which the air, having passed through the air cleaner, enters the cylinder with a temperature at the end of the inlet of 30 ... 50 ° C. When the piston reaches n. m.t., the inlet valve closes the channel and the air supply stops.

Stroke compression

On further rotation crankshaft the piston starts moving up (see Fig. 1, b) and compresses the air. Both channels are closed by valves. The air pressure at the end of the stroke reaches 3.5 ... 4.0 MPa, and the temperature - 600 ... 700 °C.

Stroke expansion, or working stroke

At the end of the compression stroke, with the piston position close to c. m.t., finely atomized fuel is injected into the cylinder through the nozzle (Fig. 1, c), which, mixing with highly heated air and gases partially remaining in the cylinder after the previous process, ignites and burns out. In this case, the pressure of gases in the cylinder rises to 6.0...8.0 MPa, and the temperature - up to 1800...2000 °C. Since at the same time both channels remain closed, the expanding gases put pressure on the piston, and it, moving down, turns the crankshaft through the connecting rod.

Release stroke

When the piston approaches n. m.t., the second valve opens the exhaust channel and the gases from the cylinder exit into the atmosphere (see Fig. 1, d). In this case, the piston, under the action of the energy accumulated during the working stroke by the flywheel, moves up, and the internal cavity of the cylinder is cleared of exhaust gases. The gas pressure at the end of the exhaust stroke is 105 ... 120 kPa, and the temperature is 600 ... 700 ° C.

On tractors, carburetor engines are used as a diesel starting device - internal combustion engines that are small in size and power, running on gasoline.
The device of these engines is somewhat different from the device of four-stroke ones. At two-stroke engine there are no valves that close the channels through which a fresh charge enters the cylinder and exhaust gases are released. The role of the valves is performed by the piston 7, which at the right moments opens and closes the windows connected to the channels, the purge window 1, the outlet window 3 and the inlet window 5. In addition, the engine crankcase is sealed and forms a crank chamber 6 where the crankshaft is located .

duty cycle of a two-stroke carburetor engine

All processes in such engines occur in one revolution of the crankshaft, that is, in two cycles, which is why they are called two-stroke.
Compression- first beat. When the piston moves up, it closes the purge 1 and outlet 3 windows and compresses the air-fuel mixture that previously entered the cylinder. At the same time, a vacuum is created in the crank chamber 6, and a fresh charge of the air-fuel mixture prepared in the carburetor 4 enters it through the opened intake port 5.
Working stroke, exhaust and intake- second beat. When the piston going up does not reach the c. m.t. at 25 ... 27 ° (according to the angle of rotation of the crankshaft), a spark jumps in candle 2, which ignites the fuel. The combustion of the fuel continues until the piston arrives at the TDC. After that, the heated gases, expanding, push the piston down and thereby make a working stroke (see Fig. 2, b). The air-fuel mixture, which is at this time in the crank chamber 6, is compressed.
At the end of the stroke, the piston first opens the exhaust port 3, through which the exhaust gases exit, then the purge port 1 (Fig. 2, c), through which a fresh charge of the air-fuel mixture enters the cylinder from the crank chamber. In the future, all these processes are repeated in the same sequence.

The advantages of a two-stroke engine are as follows.

Since the power stroke in a two-stroke process occurs for each revolution of the crankshaft, the power of a two-stroke engine is 60 ... 70% higher than the power of a four-stroke engine with the same dimensions and crankshaft speed.
The device of the engine and its operation is simpler.

Disadvantages of a two-stroke engine

Increased fuel and oil consumption due to the loss of the air-fuel mixture when the cylinder is purged.
Noise at work

test questions

1. What are internal combustion engines intended for?
Internal combustion engines are designed to convert the chemical energy of the fuel that burns inside the working cavity of the engine into thermal energy, and then into mechanical work.
2. What are the main components of the internal combustion engine?
Crankcase block, crank mechanism, gas distribution mechanism, power supply system, fuel equipment and regulator, lubrication system, cooling system, starting device.
3. List the advantages of a two-stroke carburetor engine.
Since the power stroke in a two-stroke process occurs for each revolution of the crankshaft, the power of a two-stroke engine is 60 ... 70% higher than the power of a four-stroke engine with the same dimensions and crankshaft speed. The device of the engine and its operation is simpler.
4. List the disadvantages of a two-stroke carburetor engine.
Increased fuel and oil consumption due to the loss of the air-fuel mixture when the cylinder is purged. Noise at work.
5. How are internal combustion engines classified according to the number of strokes of the working cycle?
Four-stroke and two-stroke.
6. How are internal combustion engines classified according to the number of cylinders?
Single cylinder and multi-cylinder.

Bibliography

1. Puchin, E.A. Maintenance and repair of tractors: a textbook for early. prof. education / E.A. Deep. - 3rd ed., revised. and additional - M.: Publishing Center "Academy", 2010. – 208 p.
2. Rodichev, V.A. Tractors: a textbook for the beginning. prof. education / V.A. Rodichev. – 5th ed., revised. and additional - M .: Publishing Center "Academy", 2009. – 228 p.

slide 1

Description of the slide:

slide 2

Description of the slide:

slide 3

Description of the slide:

slide 4

Description of the slide:

slide 5

Description of the slide:

slide 6

Description of the slide:

August Otto In 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 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 action 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 the efficiency of the Lenoir engine and reached 15%, that is, it exceeded the efficiency of the best steam engines of that time.

Slide 7

Description of the slide:

Slide 8

Description of the slide:

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 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 compete successfully with a gas engine, it was necessary to create a special device for evaporating gasoline and obtaining a combustible mixture of it with air. Brighton in the same 1872 invented one of the first so-called "evaporative" carburetors, but he did not work satisfactorily.

Slide 9

Description of the slide:

Slide 10

Description of the slide:

slide 11

Description of the slide:

slide 12

Description of the slide:

slide 13

Description of the slide:

Slide 14

Description of the slide:

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 - camshaft;

11 - camshaft cam;

12 - lever;

13 - valve;

14 - spark plug