Method for controlling motion of cylinder piston of piston engine and device for implementing method

Abstract

The invention belongs to the technical field of engine control, and relates to a method for controlling the motion of a cylinder piston of a piston engine and a device for implementing the method. The motion of the piston is controlled through the following steps that: A, a piston moves from a bottom dead center X1 to a position X2 upwards under the driving of a crankshaft, an exhaust valve is opened, an inlet valve is closed, and waste gas is discharged from a gas outlet; B, when the piston arrives at the position X2, the inlet valve is opened, the exhaust valve is closed, high-temperature and high-pressure combustion-supporting air is fed from the inlet valve, and the piston continues to move upwards to a position X3; C, when the piston arrives at the position X3, the inlet valve and the exhaust valve are both closed, and the piston continues to move to a top dead center X4; and D, the inlet valve and the exhaust valve are both closed, mixed gas is combusted so as to act on the piston, and the piston moves from the top dead center X4 to the bottom dead center X1. By using the method and device disclosed by the invention, under same conditions, compared with two-stroke engines and four-stroke engines, larger power, higher stability, lower noise and more significant energy saving and emission reduction can be obtained.

Description

technical field [0001] The invention belongs to the technical field of engine control, and relates to a method for controlling the motion of a cylinder piston of a piston engine and equipment for realizing the method. Background technique [0002] At present, piston engines are divided into two-stroke and four-stroke. There are three holes on the cylinder block of the two-stroke engine, namely the air intake hole, the exhaust hole and the ventilation hole. These three holes are closed by the piston at a certain moment. , two-stroke engine cylinder piston movement as figure 1 As shown, it is specifically: (1) The first stroke: the piston moves upward from the bottom dead center X1, and after the three air holes are closed at the same time, the mixed gas entering the cylinder is compressed, and when the air intake hole is exposed, the combustible mixed gas flows into the crankcase; (2) The second stroke: when the piston is compressed to the vicinity of the top dead center X4,...

AI Technical Summary

Problems solved by technology

Disadvantages of two-stroke engines: the intake and exhaust process takes a short time, so the fuel loss is large and the environmental pollution is large; there is an air port on one side of the cylinder wall, and the piston ring is easy to wear when it comes into contact with it; since the exhaust port is on the cylinder, it is easy to overheat

Disadvantages of the four-stroke engine: the engine burns once every two weeks of crankshaft rotation, so the rotation balance is unstable and the mechanical noise is large; the three-stroke intake, compression, and exhaust are all driven by the work done by the engine; the pursuit of high compression ratio and There is a great contradiction between the spontaneous combustion of fuels, which requires many means to resolve; the exhaust gas is also more serious to the environmental pollution

Among them, the turbocharger has too high requirements on the manufacturing materials and coolant due to the working environment factors, and it is often accompanied by hysteresis during the working process. It also transmits the force to the engine piston through the exhaust gas, which causes another part of useless work while saving energy; the supercharger uses the engine as the power source and consumes the work done by the engine.

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