【摘要】 为了找出伺服阀的温漂电流波动的原因,考虑到温度对主阀芯的影响,从仿真中阐述了阀芯楔形膨胀的变化规律,将阀芯轴向局部温度分布简化为一维稳态导热问题,推导了阀芯与阀套间隙的楔形变化规律表达式.在此基础上,利用滑阀间隙的流动规律,推导出了滑阀楔形变形下的库伦摩擦力表达式,得出了在库伦摩擦力下伺服阀的电流变化量.最后,通过理论分析和试验进行了对比,证明了伺服阀温漂电流的波动与温升引起的伺服阀内部非线性摩擦有关.更多还原

【Abstract】 In order to find out why temperature drift can cause current fluctuation in servo valve,the changing rules of how temperature produces a wedge effect on the spool is elaborated by simulation,in which the effect of thermal expansion on main spool is taken into consideration.The local temperature distribution in spool axial dimension is simplified to a one-dimensional steadystate heat conduction.Thus an expression which show the changing rules of the wedge-shaped clearance between the spool and spool sleeve is derived.Accordingly,a coulomb friction expression under slide valve wedge deformation is deduced based on clearance flow rules of slide valve,by which the current variable quantity of servo valve under coulomb friction is obtained.Finally,by comparing theoretical analysis and tests,it is proved that the current fluctuation in servo valve caused by temperature drift is relevant to the non-linear friction caused by temperature rise inside servo valve.更多还原