Combined air valve of high-speed diesel engine and driving mechanism thereof

Abstract

The invention provides a combined air valve of a high-speed diesel engine. The combined air valve of the high-speed diesel engine comprises a cam, a first air valve and a second air valve, wherein a first guide slot and a second guide slot are separately formed in the upper circumference of an outer contour wall; the upper end of the first air valve is connected to a first roller slidably matchedwith the first guide slot and the lower end of the first air valve corresponds to a pit of a piston; and the upper end of the second air valve is connected to a second roller slidably matched with thesecond guide slot and the lower end of the second air valve corresponds to the top of the piston. By cancelling a conventional air valve spring, the contact stress between the cam and the air valvescan be reduced effectively, the acceleration of the cam is improved, and the fullness coefficient of the cam is increased; a relatively high charging efficiency can be acquired in a high speed workingcondition while the air pit is cancelled, so that the high speed performance of the engine is improved effectively. The combined air valve is simple and compact in structure, and engineering application is facilitated.

Description

technical field [0001] The invention belongs to the technical field of engines, and in particular relates to a high-speed diesel engine combined valve and its driving mechanism. Background technique [0002] The internal combustion engine is still the prime mover with the highest thermal efficiency, the largest power per unit volume and unit weight, and 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 fuel consumption standards and emission regulations. [0003] The valves of traditional engines are equipped with valve preload springs, which makes the design of the valve mechanism of the engine take kinematics design and stress design into consideration, so as to avoid the valve flying off due to high speed and the cam wear damage caused by excessive contact stress. [0004] For diesel engines, in order to obtain a better oil-air mixing p...

AI Technical Summary

Problems solved by technology

[0004] For diesel engines, in order to obtain a better oil-air mixing process and better performance indicators, a deep pit-shaped combustion chamber with swirl (such as an ω combustion chamber) is often used; in high-speed conditions, a larger valve overlap angle is generally used (Intake valve opens early, exhaust valve closes late) to increase the charge coefficient as much as possible, and in order to prevent the diesel valve from colliding with the piston, the piston is provided with a certain depth of valve pit, but at the same time the clearance volume of the combustion chamber Increase leads to lower air utilization and combustion begins to deteriorate

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