Match On Pilot Valve Parameters And Master Valve Structure In High Flow Electrohydraulic Proportional Valve

The high pressure and large flow rate electrohydraulic proportional valve, the key part of the equipment, is the core element necessary to develop in our country.It represents the direction of the fluid control technology and the advanced international level of the proportional valve. The dissertation discusses the design methods of match on pilot valve parameter and master valve structure of the high flow rate proportional valve. The research is as follows:By analyzing the structure and principle of the high flow rate electrohydraulic proportional valve, the mathematical model of the pilot valve and the master valve is built, the expression and the relation of valve coefficient between pilot valve and master valve is shown and the effect of equivalent flow area of valve port controlled by the pilot valve on the valve coefficient is presented.The structure size of the pilot valve is theoretically calculated, and flow characteristics of different valve ports is studied. The structural parameters of valve ports in the pilot valve with U shaped notches is designed, the influence of key characteristic parameters of the valve on equivalent flow area of the pilot valve is studied, the relation between the pilot valve’s key parameters and the master valve’s coefficient is derived, and the influence regularity of the key characteristic parameters of the valve ports on the master valve coefficient is presented.The hydromechatronics simulation platform of the whole valve is built more accurately. By using this platform, the influence of the pilot valve throttling groove machining feature radius Rn on the flow output characteristics of pilot valve and the position control characteristics of master valve is studied, and the key parameter values of matching the pilot level and master level are determined.Finally, the dissertation uses the key manufacturing process of the high pressure and large flow rate electrohydraulic proportional valve to guarantee the valve manufacturing level. A comprehensive experimental platform of proportional valve is built to do experimental research on matching structure parameters of the pilot-master valves. The result shows that the experimental results and simulation results are basically the same, the influence of the key parameters of the control ports on the characteristic curve of the valve is proved, and the simulation platform is reasonable and accurate.