The Academic And Experimenting Research On The Form Error In Statistic Method

In the mechanical products,especially the mechanical products with a high precision, the geometrical error of the workpiece is important to check on the machining precision, and it is also one of the essential factors which influence the performance and the quality of the mechanical products.But the academic basic of the shape tolerance and measuring the shape error is geometrical.The center of this academic basic is the shape tolerance zone which is basede on the geometry. The method which we are using now has some strongpoints,but there are some problems in this method.The problem is that the shape tolerance which is based on the shape tolerance zone are only used to control the range of the terminal shape error. But this method does not reflect the changing character and probability of the shape error. If the new method which is about Stat.is used to scale the shape error, we can use the character that the points we have got are random.Professor Li Chunfu, comes from Northeasten University, has got some achievements in the size error which is about Statistic.Professor Li Zhu, comes from Huazhong University of Science and Technology also has got some achievements in the shape error which is about Statistic. The author has done some researching work about statistic shape error and shape tolerance.The main content of the research work is as follows.Firstly, the PMAC controller, YASKWA servo motors,and Micro-M150 precise linear movement worktable are used to make a numerical control experiment device. The servo loop PID parameters of the control system are set in detail to get the good control precision and the good stability of the control system.Second, on the basic of the former mathematic formula of the shape tolerance, the mathematic formula which is about the straightness,the paneness,the circleness and cylinder has been deduced.All the new formulas are about statistic shape error.Third,measuring experiment about straightness,planeness,circleness and cylinder has been done,and the analysis on straightness,planeness,circleness and cylinder have been made in this paper.Fourth, the author tested the experiment datas,and got certain new conclusions. Fifth, the author computed the straightness,planeness,circleness and cylinder in the method which is popular and compared the datas of straightness,planeness, circleness and cylinder with the statistic shape error.At last some certain conclusions have been got.