一种高精密液胀定位夹具的优化设计

考虑到薄壁套筒的薄壁长度、厚度,薄壁套筒环状凹槽的深度以及薄壁所受液压力的大小对工件的变形量、定位精度和夹紧力会造成影响,应用ANSYS平台对液胀定位夹具进行有限元建模,分析得出了薄壁套筒薄壁长度、厚度等参数对工件夹紧变形的影响规律,并且通过对目标进行结构优化设计,获得了优化的结构参数,优化后的结构使得液压油密封性能更好,工件和薄壁套筒变形更小,同时能够得到良好的夹紧力矩。结果表明:工件的变形量从1.5μm减小到0.9μm,薄壁套筒最大应力由292.88 MPa减小到282.34 MPa,薄壁套筒两端结合面径向变形由11.8μm减小到8.6μm,夹紧力矩由124.36 N·m减小到67.33 N·m。

Optimum Design for a High Precision Hydraulic Expansion Positioning Fixture

Considering that the length and thickness of thin-walled sleeve,the depth of ring groove of thin-walled sleeve and the magnitude of hydraulic pressure on thin-walled sleeve all affect the deformation,positioning accuracy of workpiece and clamping force on workpiece,ANSYS platform is used to model the hydraulic expansion positioning fixture with finite element,and the law of influences of these parameters on the workpiece are also analyzed.By optimizing these parameters in structural design,optimized parameters were obtained to get a better sealing performance for the hydraulic oil,smaller deformation and stress of workpieces and thin-walled sleeve,and good clamping force.The results show that the deformation of the workpiece decreases from 1.5μm to 0.9μm,the maximum stress of the thin-walled sleeve decreases from 292.88 MPa tO282.34 MPa,the radial deformation of the joint surface of the two ends of the thin-walled sleeve decreases from 11.8μm to 8.6μm,and the clamping moment decreases from 124.36 N·m to 67.33 N·m.