Research On Impact Of Electro-hydraulic Directional Valve

For a long time,electro-hydraulic reversing valve has always been one of the most important components of construction machinery.Its function is to change the flow direction of hydraulic oil,and can realize on-off,pressure unloading and sequential operation of hydraulic oil.Due to the late start of hydraulic technology in our country,the technology level of commutative valve is not high.Compared with mature products in foreign countries,the domestic electro-hydraulic commutative Valve has poor basic performance,such as pressure shock.Therefore,this paper studies the influence factors of the reversing impact of the electro-hydraulic reversing valve,in order to reduce the pressure impact of the hydraulic system and improve the stability of the hydraulic system.In this paper,a series of electro-hydraulic reversing valves made in China are taken as research objects,and the problem of pressure shock of electro-hydraulic reversing valve is studied.The theoretical calculation and simulation study are used to analyze the influencing factors of electro-hydraulic reversing valve reversing impact.By analyzing the working principle of the electro-hydraulic reversing valve,the mathematical model of the pilot spool force,the mathematical model of the main spool force,and the flow equation of the main spool are established.For the different valve port forms,the U-type and V-type valve ports are over-flowed.The area calculation formula is used to calculate the flow area of the valve port.The experimental equipment is used to measure the spring stiffness at both ends of the main valve control cavity,which lays a theoretical foundation for the construction of the system simulation platform.Based on the working principle and actual internal structure of the electro-hydraulic reversing valve,the AMESim simulation platform is established.Using the perfect simulation platform to simulate the spring stiffness on both sides of the main valve control cavity that affects the pressure of the reversing valve,the damping of the control cavity,the over-flow area of the main valve port and the damping hole of the control cavity,and determine the solution for developing low-impact electro-hydraulic valves.In order to verify the effectiveness of the proposed scheme for suppressing the impact of electro-hydraulic reversing valve,the Lab VIEW measurement and control system was built based on the experimental platform of electro-hydraulic reversing valve of Beijing Huade Multi-functional Experimental Platform.The optimization effect of the V-type valve port structure on the reversing impact of the reversing valve and the control of the electro-hydraulic reversing valve were studied experimentally.