The Dynamic Character Analysis Of Valve Port Dynamic Pressure Feed-back Direct-acting Overflow Valve

This item is a new type structure direct-acting overflow valve, which adopts dynamic pressure feedback principle. That is it adds a feedback cavity on common direct-acting overflow valve's core. When there is overfall on valve port, the hydraulic force of valve port will balance with feedback cavity's hydraulic force and spring force, so it can decrease spring's stiffness, just like adding a hydraulic spring, which works together with mechanical spring, so as to minish valve port pressure range. Through the new structure of adding feedback cavity on valve core, adjustment windage is less than 10 percent. During design, firstly, valve's structure form should be chosen according to working pressure and flow ,and valve's each part dimension should be determined according to maximum flow and experience. After spring's parameter has been ascertained by static character, by calculating open and shut characteristic, the relation curve of pressure-flow curve(P-Q curve) can be acquired. The valve's mathematical model is established by pressure distribution law of valve-port which has valve capsule surface. Dynamic character is analyzed by simulation, and sensitive parameters which effect dynamic character are found out. The prototype of machine was designed and machining according to one group of the gained optimal parameters, and the experiment is made and the result is analyzed.