RU2809172C9 - Two-stroke internal combustion engine - Google Patents

Abstract

FIELD: two-stroke internal combustion engines.

SUBSTANCE: two-stroke internal combustion engine contains a piston (5), a connecting rod, a crankshaft (20) and a working cylinder (3) with inlet and outlet ports (8) and (9). The check valve (7) is located in the inlet port (8). The crank chamber (6) is connected to the working cylinder (3) through the purge channel (10). The lubrication system is made with a dry sump (13) and an oil pan (19). The working cylinder head is made with a combustion chamber (1) with spark plugs (4) and a fuel supply device (2). The oil separator (11) is connected to the volume of the working cylinder (3) through the purge channel (10) and through an additional channel (16) to the crank chamber (6). The oil separator (11) is also connected by an oil return channel (17), through a check valve (18), to the crank chamber (6).

EFFECT: reducing the toxicity of exhaust gases and reducing oil consumption.

1 cl, 1 dwg

Description

The invention can be used in two-stroke internal combustion engines.

There is a known lubrication system for a two-stroke internal combustion engine (ICE) with crank-chamber purging, protected by RF patent No. 2773168, which is designed to lubricate the piston-cylinder friction pair of the engine with engine oil, and the connecting rod and main bearings with grease, while the system contains a container with engine oil, a pipeline with a dispenser for supplying oil from the container to the hole in the engine cylinder, oil seals are installed in the connecting rod and main bearings.

The well-known lubrication system for a two-stroke internal combustion engine makes it possible to reduce oil consumption due to the separate supply of oil and fuel to the working cylinder. Reducing oil consumption leads to a decrease in the amount of harmful substances released into the atmosphere, and therefore to an increase in the environmental friendliness of the engine. However, the use of grease in connecting rod and main bearings results in frequent checking of the presence of grease in them and, if necessary, replenishing it in the bearings. If, due to an oversight, there is no lubrication in the bearings or there is insufficient lubrication, the engine may fail. Also, during engine operation, excess motor oil supplied to lubricate the piston-cylinder friction pair falls on the rotating parts of the crank mechanism, breaking against them, turning into a state of oil mist and, mixing with air in the crank chamber, forming an oil-air mixture, which It enters the working cylinder through the purge channel, and after the power stroke, incompletely burned oil is discharged through the outlet window into the atmosphere, which leads to environmental pollution.

The Rotex 850 E-Tekc two-stroke internal combustion engine is known, adopted as a prototype, electronic source (https://yandex/ru/video/preview/157787741052075815034) - (video 1) and (https://www.youtube.com/watch?v= HbKdIbOUhrk) - (video 2) access date 06/22/2023, which contains a working cylinder, a piston, a connecting rod, an inlet and outlet port, a purge channel, a crank chamber, and a container with engine oil. The container with engine oil is connected through a feed pump to the oil supply channel in the support bearing. The oil channel in the support bearing is connected by an oil channel in the crankpin bearing. Lubrication of the walls of the working cylinder is carried out due to the fact that oil is squeezed out from the connecting rod journal bearing and the internal bearing and in contact with the rotating parts of the crank mechanism, oil mist is formed, which with the air in the crank chamber forms an oil-air mixture, which enters the working cylinder. The cylinder through the purge channel lubricates the walls of the working cylinder, and after the power stroke, incompletely burned oil flies out through the outlet window into the atmosphere, which leads to environmental pollution. The author of video 1 claims that oil flows from the internal bearings into the cavity where the axis of rotation of the pump is located, then from this cavity the oil flows through the return oil line into the oil tank. However, in video 2, the author admits this is a mistake and claims that excess oil from the internal bearings enters the crank chamber.

The prototype engine uses separate supply of fuel and oil to the working cylinder, which reduces oil consumption due to the fact that gasoline does not wash off the oil film from the cylinder during engine operation and oil is separately and forcibly supplied to the bearings of the crank mechanism. Part of the oil from the bearings of the crank mechanism enters the crank chamber, forming an oil-air mixture with the air in the crank chamber, which enters the working cylinder through the purge channel, and after the power stroke, incompletely burned oil is thrown out through the outlet window into the atmosphere, which leads to to environmental pollution.

However, oil consumption remains high compared to oil consumption in a four-stroke internal combustion engine.

Therefore, the technical result of the proposed two-stroke internal combustion engine is to reduce the toxicity of exhaust gases and oil consumption.

The result is achieved by the fact that a two-stroke internal combustion engine, which contains a piston, connecting rod, crankshaft, a working cylinder with inlet and exhaust ports, a check valve located in the intake port, a crank chamber connected to the working cylinder through an oil separator and a purge channel, a system dry sump lubrication and a “sump” for oil, a working cylinder head with a combustion chamber with spark plugs and a fuel supply device. Unlike the prototype, the oil separator is connected to the working cylinder volume through a purge channel and through an additional channel to the crank chamber, and is also connected to the crank chamber by an oil return channel through a check valve. The check valve located in the oil return channel opens when the air in the crank chamber is discharged when the piston moves to top dead center (TDC) and at the same time the oil separator clears the collected oil into the crank chamber and prevents the flow of air between the crank chamber and the working cylinder.

The proposed engine ensures cleaning of the oil-air mixture coming from the crank chamber into the working cylinder through an oil separator, an additional channel with the crank chamber and a purge channel from the oil. Through the oil return channel connecting the oil separator to the crank chamber, filtered oil flows back into the oil pan and then through the dry sump lubrication system the oil is returned to the oil tank, thereby reducing oil consumption and eliminating its release into the atmosphere, which increases environmental friendliness of the engine.

The proposed internal combustion engine is illustrated by the sketch of Fig. 1, which shows the general diagram of the engine.

The proposed engine works as follows.

Fuel is supplied to the combustion chamber 1 through the fuel supply device 2, forming a fuel-air mixture in the working cylinder 3, which is ignited using a spark plug 4. As a result of ignition of the fuel-air mixture, the working piston 5 moves from top dead center (TDC) to bottom dead current (BDC), rotating the crankshaft 20. When the working piston 5 moves down, a pressure is created in the crank chamber 6, which closes the check valve 7 in the inlet window 8. With further movement of the working piston 5, the outlet window 9 and the purge channel 10 with an oil separator open 11. Oil from the oil tank 12 is supplied under pressure through the dry sump lubrication system 13 to the support bearing 14 and to the crankpin bearing 15. When the engine is running, oil is squeezed out of both bearings 14, 15 and enters the crank chamber 6. In contact with rotating parts break the oil, forming an oil mist that lubricates the walls of the working cylinder 3. When the purge channel 10 is opened, the oil-air mist, passing through an additional channel 16 with the crank chamber 6, enters the oil separator 11, the oil is filtered and flows into the oil return channel 17 to the check valve 18, which opens towards the crank chamber 6. Filtered air enters from the oil separator 11 through the purge channel 10 into the working cylinder 3. When the working piston 5 moves to (TDC), the pressure in the crank chamber 6 decreases below atmospheric pressure, the check valve 18 opens and 7. Through the open check valve 18, the filtered oil enters the “sump” for oil 19, from which the oil through the dry sump lubrication system 13 enters the oil tank 12, and through the open check valve 7 atmospheric air enters the crank chamber 6 for next cycle.

Claims (1)

A two-stroke internal combustion engine comprising a piston, a connecting rod, a crankshaft, a working cylinder with intake and exhaust ports, a check valve that is located in the intake port, a crank chamber connected to the working cylinder through a purge port, a dry sump lubrication system, and a sump for oil, a working cylinder head with a combustion chamber with spark plugs and a fuel supply device, characterized in that the oil separator is connected to the volume of the working cylinder through a purge channel and through an additional channel with the crank chamber, and is also connected to an oil return channel, through a check valve, with crank chamber.