Variable-combustion-chamber two-stroke gasoline engine

Abstract

The invention discloses a variable-combustion-chamber two-stroke gasoline engine comprising a cylinder sleeve, a top plug and a top plug cover. A through hole used for correspondingly holding a pistonis arranged at the center of the cylinder sleeve. The two sides of the hole wall on the lower part of the through hole are provided with an exhaust hole and an intake hole. The intake hole is lower than the exhaust hole. The upper portion of the cylinder sleeve is provided with a spark plug corresponding to the through hole in position. The portions, corresponding to the two sides of the intake hole, of the hole wall of the through hole are each provided with a ventilation groove. The groove top of each ventilation groove is provided with an oil-air channel communicating with the top face ofthe cylinder sleeve. By the adoption of the variable-combustion-chamber two-stroke gasoline engine, residual waste gas on the upper portion inside the cylinder sleeve can be discharged out of the cylinder sleeve, so that more fresh oil-air can be sucked in, the combustion efficiency of the engine is improved beneficially, the oil consumption and the discharge mount of the waste gas are reduced, lubricating, cleaning and cooling conducted inside the cylinder sleeve can be assisted, and the service life of the engine is prolonged.

Description

technical field [0001] The invention relates to the technical field of two-stroke gasoline engines, in particular to a two-stroke gasoline engine with a variable combustion chamber. Background technique [0002] The two-stroke gasoline engine currently used in garden machinery such as chainsaws and light propeller aircraft was invented by the Frenchman Colmery in 1900. Compared with the four-stroke engine, it has a simple and unique structure, low cost, and oil-air lubrication. These two advantages of high speed are still unattainable by the current four-stroke engine; but it also has the disadvantages of fuel consumption and large exhaust emissions caused by gasoline not being able to burn quickly and fully due to dirty ventilation. The effect is poor, resulting in high friction loss and low life of the engine; the reason for the dirty ventilation of the two-stroke engine is its own structural performance. At the end of the stroke, during the period when the piston descend...

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Problems solved by technology

[0002] The two-stroke gasoline engine currently used in garden machinery such as chainsaws and light propeller aircraft was invented by the Frenchman Colmery in 1900. Compared with the four-stroke engine, it has a simple and unique structure, low cost, and oil-air lubrication. These two advantages of high speed are still unattainable by the current four-stroke engine; but it also has the disadvantages of fuel consumption and large exhaust emissions caused by gasoline not being able to burn quickly and fully due to dirty ventilation. The effect is poor, resulting in high friction loss and low life of the engine; the reason for the dirty ventilation of the two-stroke engine is its own structural performance. At the end of the stroke, during the period when the piston descends to the exhaust hole and the ventilation groove, the exhaust gas generated by the combustion in the cylinder will be discharged from the cylinder through the exhaust port by its own pressure because the pressure of the exhaust gas generated by combustion in the cylinder is higher than that of the outside atmospheric pressure; the piston continues to descend to expose the exhaust gas. After the air groove, the oil gas with high compression pressure in the crankcase enters the cylinder with low pressure, and at the same time, part of the exhaust gas is squeezed out of the cylinder;

[0003] Since the ventilation groove and the exhaust port are at the bottom, and the height difference is not large; so the exhaust gas in the lower part of the cylinder is easily squeezed out of the cylinder through the exhaust port, and most of the exhaust gas in the upper part of the cylinder cannot be squeezed out of the cylinder, because There is no exhaust port on the upper part of the cylinder, so the oil gas entering from the crankcase cannot reach the upper part of the cylinder, and the exhaust gas from the upper part will be released; in addition, because the crankshaft, connecting rod and other parts need to be installed in the crankcase, the internal space is large, so that the piston moves upward The air intake efficiency is reduced, and the amount of fresh oil and gas sucked into the crankcase and pressed into the cylinder is less than the amount of exhaust gas that exists in the cylinder and needs to be discharged; resulting in unclean ventilation of the two-stroke engine, resulting in low combustion efficiency of the engine, resulting in fuel consumption and large exhaust emissions, for this reason, we propose a variable combustion chamber two-stroke gasoline engine to solve the above problems

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