图1所示的零件,按图纸要求,检查齿圈的径向跳动误差,本应以A—B公共轴线为基准进行。但目前对类似图1所示零件的检查还存在着两个难以解决的问题。一是基准体现困难,按图纸要求检测十分不便;二是形状误差难以测量。笔者认为,如把齿圈近似地看作理想圆柱,用打径跳的方法测出同轴度,就能较好地解决上述问题。下面首先将这一问题抽象成数学模型,然后分析其解决办法。 Parts shown in Figure 1, according to the requirements of the drawings, check the radial runout error of the ring gear, the A-B should be based on the common axis. However, there are still two unresolved problems with the inspection of parts like the one in Figure 1. First, the benchmark reflects the difficulties, according to the drawings required testing is very inconvenient; the second is difficult to measure the shape error. The author believes that if the ring gear is approximately regarded as an ideal cylinder, measured by the method of hitting the coaxiality, we can better solve the above problems. The following first abstract the problem into a mathematical model, and then analyze the solution.