Mathematical models at different valve opening degree, aimed at digital electro-hydraulic proportional controller design has excellent control performance...

Electro-hydraulic proportional control technology with high control accuracy, easy adjustment, the relative electro-hydraulic servo valve, with a better price advantage, currently in the industrial field, heavy machinery and other production areas have a more widely used. Electro-hydraulic proportional control of the core technologies in the closed-loop algorithm design, flutter superimposed signals, dead-time control and so on. On the basis of analyzing the characteristics of the proportional flow valve, the establishment of a mathematical model of the valve opening at different degrees, aimed at digital electro-hydraulic  Instrument valve manifolds  controller design has excellent control performance. Proportional flow valve core structure diagram is generally proportional flow by the throttle valve heart, springs, and some contain pressure compensator. This paper studies the proportional flow valve composed by the three-part series,  Compression fitting  principle. Spool movement to establish the mechanical model paper analyzes the influence of the force spool only steady state, ignoring the transient fluid dynamics and the oil outlet steady flow force, mainly analyzes the electromagnetic force, the inlet steady flow force, the spring force , fluid pressure.

Soft spool off easily, more difficult to deal with

As the valve core material is soft PVC, low strength, deformation, coupled with the use of the stem and the valve plug socket  Instrument valves , not only with the two facets, and the stem easy displacement. Thus, soft spool off easily deal with them more difficult. To this end, in the end face of the original spool of welding a piece of  Compression fitting  plate, completely solve the problem of the spool off. The specific method is to remove the spool system with a hard thick PVC plate stiffeners do smm, its outer diameter smaller than the outer diameter of about spool 10mm, to facilitate welding; width slightly larger than the diameter of the stem to facilitate flexible stem rotation.