【摘要】 采用电流变液微阀门控制盲文凸点显示矩阵具有低成本,能耗少,易于控制等优势.每个盲文凸点都有独立控制的应用需求,决定了电流变液微阀门需要采用并联结构,因此,并联阀门性能一致性成为盲文凸点能否正确显示的重要因素.就电流变液微阀门的结构而言,这种性能一致性取决于阀门加工的公差带选择.盲文凸点的高度取决于同一给定压力下各阀门输出的流量,不同的公差带对应着不同的阀门阻力,影响着阀门的输出流量,阀门间的流量差异过大会导致盲文凸点的误显示.该文系统分析了阀门结构参数波动对阀门阻力和流量的影响规律,给出了电流变液微阀门加工公差带选择依据的数学模型,并通过注塑加工方式制作了并联式电流变液阀门.测试结果表明,根据模型选定的公差带内的并联阀门,能够显示符合盲文标准的盲文凸点,满足应用需求.更多还原

【Abstract】 The merits of using electrorheological(ER)fluids micro valves to manipulate Braille dots matrix are easy to control with lower costs and power consumptions.The architecture of ER micro valves in Parallel ducts is due to the application demand that each of dots needs to be manipulated independently.Then,the performance consistency of parallel ducts becomes the vital factor of displaying a Braille dot in a right way.As far as the dimensions of ER micro valves were concerned,the performance consistency of ER micro valves is decided by the selections of their machining tolerances.The heights of Braille dots lie on each flux of parallel ducts under a same given pressure.And different machining tolerances make different drops of pressures of ER micro valves and bring the different fluxes of parallel ducts.A mis-displaying of braille dots will occur when different fluxes among the parallel ducts beyond a limited value.The effects of fluctuations of dimensions of ER micro valves on the drops of pressures and fluxes of parallel ducts were investigated systematically,a mathematic model for selecting the machining tolerates of dimensions of parallel ducts of ER micro valves was given in the paper.ER micro valves matrixes with parallel ducts were manufactured by injection molding in selected tolerances using the mathematic model.The testing results showed that the heights of Braille dots meet the demands of Braille standard and applications.更多还原