RU2398118C1 - Piston engine with external combustion chamber - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention relates to automotive industry. Proposed engine comprises external combustion chamber with nozzle and spark plug, gas control valve, bypass valve and air intake valve, power piston and compressor piston with crank drives, coupling shaft, flywheel and p.t.o.-shaft. Note here that conversion of fuel chemical energy into mechanical power is divided into fuel combustion in external combustion chamber and expansion of combustion products in the cylinder of piston expander. In compliance with this invention, proposed engine incorporates pneumatic accumulator wherein air is forced from compressor head-end space to add air into external combustion chamber in combustion process.

EFFECT: higher specific power and possibility to run on various fuels.

1 dwg

Description

Technical field

The invention relates to the field of power engineering.

BACKGROUND

The closest analogue of the claimed invention is an external combustion engine, a Stirling engine (Large Polytechnical Dictionary POLYTECHNIC, Scientific Publishing House "Big Russian Encyclopedia, M .: 1998, p. 505, 506). External combustion engine - an engine with an external supply and regeneration of thermal energy, converted into useful mechanical work. The modern Stirling engine operates in a closed regenerative cycle, consisting of two isothermal and two isochoric processes sequentially alternating. Unlike the Stirling engine in the proposed piston engine with an external combustion chamber, the fuel combustion process is carried out in an external combustion chamber with the subsequent supply of combustion products to the cylinders of a two-stroke piston expansion machine, where the energy of expanding combustion products is converted into mechanical shaft rotation energy.

SUMMARY OF THE INVENTION

The invention is illustrated by a description of the principle of operation of a piston engine with an external combustion chamber.

The engine consists of (see drawing): 1 - combustion chamber, 2 - nozzle, 3 - spark plug, 4 - gas distribution valve, 5 - power piston, 6 - crank mechanism of the power piston, 7 - connecting shaft, 8 - crank mechanism of the compressor piston, 9 - compressor piston, 10 - bypass valve, 11 - pneumatic accumulator, 12 - flywheel, 13 - air intake valve, 14 - exhaust channel, 15 - power take-off shaft.

When the engine is started, fuel is injected into the combustion chamber 1 by the nozzle 2 and ignited by the spark plug 3. The combustion products from the combustion chamber 1 through the gas distribution valve 4 (the valve is in the rightmost position) enter the over-piston cavity of the power piston 5. Here, the expanding combustion products affect the power the piston 5, and it starts to move down. The translational movement of the piston 5 by the crank mechanism 6 is converted into the rotational motion of the connecting shaft 7, which is transmitted to the crank mechanism of the compressor 8 so that the piston of the compressor 9 moves up. Compressed air in the piston cavity of the compressor piston 9 through an open bypass valve 10 enters the combustion chamber 1 and the pneumatic accumulator 11, replenishing the flow of oxygen in the combustion chamber 1 during fuel combustion and charging the pneumatic accumulator 11. After the power piston 5 is at bottom dead center and the compressor piston 9 is at top dead center, the kinetic energy of the flywheel 12 changes the direction of movement of both pistons. The bypass valve 10 closes, and the air inlet valve 13 opens, and air from the atmosphere enters the piston cavity of the piston of the compressor 9. At the same time, the gas distribution valve 4 is moved to the left extreme position and the exhaust products of combustion through the exhaust channel 14 are released into the atmosphere. During this cycle, the combustion process in the combustion chamber 1 is supported by air coming from the pneumatic accumulator 11. At the end of the cycle, the gas distribution valve 4 is again moved to the left position, the bypass valve 10 and the air intake valve 13 come to their original positions, and the next working cycle begins. The area of the power piston 5 is larger than the area of the piston of the compressor 9, and therefore, the air pressure at the inlet to the combustion chamber 1 is greater than the pressure of the products of combustion at its output, which ensures the efficiency of the engine. The energy on the power take-off shaft 15 is determined by the difference between the average pressure of the combustion products in the supra-piston cavity of the power piston 5 and the average air pressure in the supra-piston cavity of the compressor 9.

SUMMARY OF THE INVENTION

A piston engine with an external combustion chamber, comprising an external combustion chamber with a nozzle and spark plug, a gas distribution valve, an overflow valve and an air intake valve, a power piston and a compressor piston with crank mechanisms, a connecting shaft, a flywheel and a power take-off shaft, the process the conversion of chemical energy of fuel into mechanical energy is divided into the process of fuel combustion in the external combustion chamber and the process of expansion of the combustion products in the piston cylinder th machine, characterized in that the engine is equipped with a pneumatic accumulator, the air into which comes from the supra-piston cavity of the compressor and which replenishes the external combustion chamber with air during the combustion of the fuel.

INDUSTRIAL APPLICABILITY

A piston engine with an external combustion chamber is intended for use as a general-purpose mechanical drive, including as a power unit of vehicles for all purposes. Here we examined the principle of the engine with one cylinder of the power piston and one cylinder of the compressor. A relatively stable moment of force on the power take-off shaft is provided in an engine with two power cylinders. With three power cylinders and more, it is possible to change the direction of rotation of the power take-off shaft by changing the operating order of the gas distribution valves in the cylinders. As for the uniformity of air supply to the combustion chamber, it is ensured by the optimal ratio of the number of compressor cylinders and the capacity of the pneumatic accumulator. This ratio has an inverse relationship. The larger the capacity of the pneumatic accumulator, the smaller the number of compressor cylinders and vice versa. The two-stroke engine doubles its power density compared to a four-stroke engine. Separation of the processes of fuel combustion and expansion of the combustion products provides multi-fuel - you can use any motor fuel, both liquid and gaseous, without changing the fuel equipment. Fuel combustion occurs at a stoichiometric ratio of fuel-oxidizer to the final combustion products, without leaving oxygen to form nitrogen oxides. In addition, the engine has a favorable traction characteristic when used as a power unit of a car. The greater the load on the engine, the more, to certain limits, the higher the pressure of the combustion products, and the greater the moment of force on the shaft. The requirements for materials and technology do not go beyond modern requirements.

GRAPHIC MATERIAL

Drawing. Schematic diagram of a piston engine with an external combustion chamber.

1 - combustion chamber, 2 - nozzle, 3 - spark plug, 4 - gas distribution valve, 5 - power piston, 6 - crank mechanism of the power piston, 7 - connecting shaft, 8 - crank mechanism of the compressor piston, 9 - piston compressor, 10 - bypass valve, 11 - pneumatic accumulator, 12 - flywheel, 13 - air intake valve, 14 - exhaust channel, 15 - power take-off shaft.

Claims (1)

A piston engine with an external combustion chamber, comprising an external combustion chamber with a nozzle and spark plug, a gas distribution valve, an overflow valve and an air intake valve, a power piston and a compressor piston with connecting rod and crank mechanisms, a connecting shaft, a flywheel and a power take-off shaft, the process the conversion of chemical energy of fuel into mechanical energy is divided into the process of fuel combustion in the external combustion chamber and the process of expansion of the combustion products in the piston cylinder machine, characterized in that the engine is equipped with a pneumatic accumulator, the air into which comes from the supra-piston cavity of the compressor, and which replenishes the external combustion chamber with air during combustion.

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