水压伺服阀液压桥路的正交设计与分析

Orthogonal Design and Analyses of Hydraulic Bridge for Water Servo Valve

提出了一种前置级采用两级串联固定阻尼孔的双喷嘴挡板水压伺服桥路模型,并对其进行了参量敏感性分析。探讨了喷嘴挡板位移、阀芯运动速度与阀芯两端压力的关系;运用正交设计方法研究了喷嘴直径、串联固定阻尼孔直径、阀芯直径及其运动速度、喷嘴挡板与喷嘴之间初始距离等参量对水压桥路特性的影响。结果表明,喷嘴直径以及喷嘴与挡板之间中位距离越小,阀芯与阀套之间配合间隙越大,阀芯直径越大,阀芯与阀套之间叠合长度越短,压力源压力越高,桥路控制的线性度越好;对于采用二级节流的水压伺服桥路,第一级固定阻尼孔直径越小,第二级固定阻尼孔直径越大,喷嘴前端流道直径越小,阀芯与阀套之间配合间隙以及阀芯直径越大,桥路响应就越快。这些研究结果为水压伺服阀样机的研制奠定了理论基础。

A new type of double nozzle-flapper water hydraulic servo bridge model is developed, in which the two tandem fixed dampers are adopted as prepositive dampers. The parameter sensitivity analysis for the hydraulic bridge is carried out. The relationship among the flapper displacement, the spool speed and the pressure at the two ends of the spool is investigated. The orthogonal design is employed to study the influence of the physics factors on the characteristics of the hydraulic bridge, such as the diameter of the nozzle, the diameters of the two tandem fixed dampers, the spool diameter and its sliding speed, the initial clearance between nozzle and flapper. The results reveal that （1） the smaller initial clearance between nozzle and flapper, the larger diam eter of spool and the clearance between spool and valve body, the shorter overlap length of spool and valve body, and the higher system pressure, will lead to the better linearity of the control characteristics for the water hydraulic bridge; （2） for hydra ulic bridge of water servo valve including the two-stage dampers, the smaller first damper diameter, the larger second damper diameter, the smaller pipe diameter before the nozzle, the larger diameter of spool and the clearance between spool and valve body, will bring the higher dynamic response in the water hydraulic bridge. These research results will lay the theoretical foundation for the development of water hydraulic servo valve.