针对在加工大导程滚珠螺母时,可能会出现砂轮磨杆与螺母端面发生干涉的问题,从滚珠螺母磨削加工的基本方法出发,依据砂轮回转面与被加工螺母内滚道面包络的接触线是一条空间曲线的原理,建立任意安装角度下砂轮回转曲面的计算模型,并将此计算模型用于解决大导程滚珠螺母加工干涉问题。提出在保证加工时不发生干涉的前提下,选取砂轮最佳安装角和中心间距参数的方法以及在此参数下砂轮廓形的拟合优化方法。该方法计算简单、可以随时根据安装角和中心间距参数值对砂轮廓形进行修整,以保证磨削精度。以某型号大导程滚珠螺母为例,完成在保证不发生干涉的情况下相关工艺参数的选择以及砂轮廓形的优化设计,对结果进行误差分析,验证了方法的有效性。
In order to solve interference between wheel shaft and internal surface of ball-nut in the process of high-lead ball-nut grinding, a method for Gothic arc grinding of high-lead ball-nut is presented. The presented method is based on the theoretical fundament of helicoids shape grinding. According to the principle that the contact points of the grinding wheel and the internal surface of the ball-nut form a space curve, a calculation model is established for surface calculation of the grinding wheel, by which collision can be avoided. The method is applicable to calculate the profile of grinding wheel in any angle, as well as to choose the best process parameters for the shape grinding. This method is simple and convenient for modification of grinding wheel shape when it needed. Lastly, taking a high-lead ball-nut as an example, the validity of the method is approved by grinding wheel optimum profile calculation and error analyze of the results.