Fully variable electro-hydraulic valve system

Abstract

The invention discloses a fully variable electro-hydraulic valve system. The full-variable electro-hydraulic valve system comprises a limiting sleeve, a sliding sleeve, a spiral shaft, a piston and areset spring, wherein the limiting sleeve is fixed relative to an engine, the sliding sleeve is rotatably mounted with the limiting sleeve, the sliding sleeve is constrained by an axial limiting structure, the sliding sleeve is in transmission connection with a gear rack mechanism, the piston abuts against a valve assembly, and the spiral shaft is axially controlled by the cam surface of a camshaft; the spiral shaft is provided with a spiral groove and a plugging part, and when the spiral groove communicates with a limiting oil hole, a sliding sleeve cavity communicates with a low-pressure oilpath of the engine to relieve pressure; and the axial protrusion portion of the spiral shaft is provided with a spiral shaft abutting plane, and the head portion of a piston axial protrusion portionis provided with a piston abutting plane. According to the invention, the problem that the oil loss in the sleeve cavity affects the normal operation of the system is solved, the crank angle corresponding to the valve opening moment is kept unchanged, and the system is particularly suitable for controlling the variable stroke of the intake valve of the engine with scavenging process.

Description

technical field [0001] The invention relates to the technical field of engine valve mechanism, in particular to a fully variable electro-hydraulic valve system. Background technique [0002] Fully Variable Valve System (FVVS for short) can realize the continuous variable of the maximum valve lift, valve opening duration angle and valve timing, which is of great significance to the energy saving and emission reduction of the engine. FVVS can control the amount of working fluid entering the cylinder by means of early intake valve closing (EIVC), thereby canceling the throttle valve. This throttleless gasoline engine will greatly reduce the pumping loss and reduce the fuel consumption under small and medium loads. 10-15%. The fully variable valve mechanism is matched with supercharging and intercooling, which can solve the problems of engine deflagration and high heat load after supercharging, realize low-temperature combustion under the premise of greatly increasing the avera...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the above-mentioned shortcomings of the prior art, the present invention provides a fully variable electro-hydraulic valve system to solve the problem that the normal operation of the system is affected by the loss of oil in the sliding sleeve cavity, and to make the crank angle corresponding to the opening moment of the valve constant

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