A Variable Valve Mechanism Capable of Realizing 2/4 Stroke Interchange

Abstract

The invention provides a variable valve mechanism capable of realizing 2 / 4 stroke interchange. The variable valve mechanism comprises a cam, two rocker arms, two linear reciprocating devices and a valve, wherein the cam is provided with two types of lines, the two rocker arms respectively correspond to the two type of lines, the two linear reciprocating devices are respectively used for driving the two rocker arms, and the valve is provided with a pre-tightening spring. The magnitude and the direction of the acting force of the two linear reciprocating devices on the two rocker arms are respectively adjusted, so that the variable 2 / 4 stroke and variable valve lift can be changed. The system does not need to be operated under each working cycle, and the parameters can be adjusted only underthe working condition that the valve movement rule needs to be changed, so that the cost of the valve can be obviously reduced on the basis that the movement of the valve is flexible and variable, the service life of components can be prolonged, and engineering application of the variable valve technology is facilitated.

Description

technical field [0001] The invention belongs to the technical field of engine variable valves, in particular to a variable valve mechanism capable of realizing 2 / 4 stroke interchange. Background technique [0002] The internal combustion engine is still the prime mover with the highest thermal efficiency and the largest power per unit volume and unit weight. It is widely used. However, with the gradual shortage of energy in the world and the continuous deterioration of environmental resources, we need internal combustion engines to meet stricter emission regulations. Traditional internal combustion engines use fixed-profile camshafts to drive valves, which makes the emissions and fuel consumption of internal combustion engines not optimal at all operating points. Therefore, most new internal combustion engines use variable valve technology to control emissions and reduce fuel consumption. [0003] At present, variable valve technology is mainly divided into camshaft-based va...

AI Technical Summary

Problems solved by technology

Compared with the disadvantages of high energy consumption of electromagnetic drive, low and unstable response speed of electric drive, and complex motor-driven system, the camless gas distribution technology of electro-hydraulic drive has relatively simple structure and fast response speed

However, it also has unavoidable disadvantages: the flow rate of the hydraulic system is not enough at high speed, the valve reaches the maximum lift and the seat is fast, and the impact force is large.

Therefore, it is mainly used in low-speed engines such as diesel engines. In addition, it is necessary to use expensive electro-hydraulic servo systems and relatively complex control technologies to accurately control the valve stroke to avoid seating impact, which greatly increases the engine. cost

Images