The On-line Measurement Of Gap Roundness Error And Straightness Error And The Research On Monitoring Technology

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. Roundness and straightness are the important elements to express figure of the accessory, each of them plays an important role and has very important effect. There are some progresses in the measuring technologies of the two geometrical errors, but the research still is not enough in the fields and can not meet the requirements. The research of roundness error mainly focuses on the complete profile. In practice there are some incomplete profiles and the research of roundness error on them is little.The research work in this paper is to resolve the on-line measurement of straightness error and the roundness error calculation of the incomplete profile. Based on the research of the roundness error theory of complete profile and the technology of the two-probe straightness error separation, the least square mathematical model of the incomplete profile is established and a long distance straightness error separation monitoring virtual instrument based on the LabWindows/CVI is designed. The on-line measurement of the straightness error and roundness error is realized and it will increase the precision of machining. The main content of the research work is as follow.Firstly, in the research on the complete profile roundness error, the least square mathematical model of the incomplete profile is established and the model is proved correct by the simulation and the experiment.The roundness error separation theory by two contraposition probes is applied to the measurement of the incomplete profile roundness error and it is proved correct by the simulation and the experiment. Although the theory can not eliminate the influence of the rotating error completely, the results by the two probes are much better than that of the one probe in the measurement of the gap roundness error.The mathematical model of two-probe straightness error separation is deduced and it is proved that the original error accumulation can not influence the separated straightness error by the simulation and experiment. This error separation method can be used to assess the straightness error.At last, a long distance straightness error separation monitoring virtual instrument based on the LabWindows/CVI is designed. The instrument has the function of transferring the data, controlling the measurement progress, assessing the straightness error and so on. Some amendatory steps are given to the testing experiment.