Method for implementing increment of expansion ratio of reciprocating intermal-combustion engine and control of compression ratio

Abstract

The present invention discloses a method for increasing expansion ratio of reciprocating internal combustion engine and controlling its compression ratio. Said method utilizes the regulation of maximum volume V2 and minimum volume V1 of the cylinder to make the expansion ratio V2 / V1 be increased, and utilizes change of cam form and port timing of air inlet and outlet valves to make the effectively-compressed actuating meduim volume be V3, V1 less than V3 less than V2, the compression ratio is V3 / V1, so that it can target the goal of increasing engine thermal powder conversion.

Description

technical field [0001] The invention relates to an internal combustion engine, in particular to a method for increasing the expansion ratio of a reciprocating internal combustion engine and controlling the compression ratio. Background technique [0002] The internal combustion engine is regarded as the heart of the car, and the performance of the internal combustion engine determines the quality of the car. The thermal efficiency of reciprocating internal combustion engines widely used at present is relatively low, so it is particularly important to improve the economic performance of internal combustion engines. The work expansion ratio of the current four-stroke internal combustion engine is equal to the compression ratio. After the work is done, the working medium still has a certain pressure. At this time, the working medium still has the ability to work externally. By increasing the expansion ratio, more heat conversion can be realized, but Excessive compression ratio...

AI Technical Summary

Problems solved by technology

At present, the thermal efficiency of reciprocating internal combustion engines used in large quantities is relatively low, so it is particularly important to improve the economic performance of internal combustion engines

The work expansion ratio of the current four-stroke internal combustion engine is equal to the compression ratio. After the work is done, the working medium still has a certain pressure. At this time, the working medium still has the ability to work externally. By increasing the expansion ratio, more heat conversion can be realized, but Excessive compression ratio makes the internal combustion engine unable to work normally, and the expansion ratio is limited by the compression ratio. This part of heat conversion is not realized, but is discharged from the cylinder

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