Variable-compression-ratio internal combustion engine

Abstract

The invention provides a variable-compression-ratio internal combustion engine which changes the compression ratio of the internal combustion engine by changing the volume of a combustion chamber. Thevariable-compression-ratio internal combustion engine comprises a gas feeding door, a gas exhausting door, an assisting piston, an assistant connecting rod, an assistant cylinder, an assistant crankshaft, an assistant crankshaft running and adjusting mechanism and other parts of the internal combustion engine, wherein the assistant crankshaft running and adjusting mechanism comprises a control motor, a chain wheel, an inner gear ring, an eccentric bearing, a planetary wheel and an assistant crankshaft gear; a crankshaft and the assistant crankshaft of the internal combustion engine rotates atspeed ratio of 2: 1 or 1: 1. When the assistant crankshaft running and adjusting mechanism does not adjust, the compression ratio of the internal combustion engine is unchanged. When a piston expandsand act, the assistant piston expands and acts, so that the internal combustion is capable of changing the expansion ratio.

Description

technical field [0001] The invention relates to an internal combustion engine technology, in particular to an internal combustion engine with variable compression ratio and variable expansion ratio. Background technique [0002] There are many patents for variable compression ratio internal combustion engines. At present, there is only one type of variable compression ratio internal combustion engines that are actually commercially available: multi-link mechanism. [0003] A US Patent (Patent No. 4,516,537) discloses a device for further changing the compression ratio of an internal combustion engine by adding a movable auxiliary piston in the combustion chamber to change the volume of the combustion chamber. [0004] Other US patents 4987863, 5195469, 6427643, 6708655, 8418663, 7387103 and 7856952 etc. all have similar ideas. [0005] This mechanism has many advantages, such as low cost, compact structure, etc., but its disadvantages are: no matter whether the auxiliary pi...

AI Technical Summary

Problems solved by technology

[0005] This mechanism has many advantages, such as low cost, compact structure, etc., but its disadvantages are: no matter whether the auxiliary piston is driven mechanically or hydraulically to move in the auxiliary cylinder, the auxiliary piston is fixed in the auxiliary cylinder when the compression ratio does not need to be changed. In this way, when carbon deposits occur around the auxiliary piston and the auxiliary cylinder, the carbon deposits cannot be removed. When the carbon deposits are severe, the auxiliary piston will also be stuck. At the same time, the auxiliary piston cannot be effectively cooled and Lubrication, thus losing the function of variable compression ratio

These disadvantages prevent this structure from being commercialized

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