In-process roundness measurement system for cylindrical machine parts of small diameter w|th run-out error compensation

本课题的研究目的是开发一种能够同时评价车削圆柱形零件圆度和车床主轴回转误差的在线测量系统。被测圆柱形零件直径小于2 mm，系统的目标测量精度为亚微米级。该系统由测量仪器、信号处理设备和数据分析系统组成。所开发的系统的测量仪器包括三个光学传感单元。每个单元有一个平行的光束和双光电二极管来检测不对称的光束功率分布，在三个光束的交叉点内设置一个圆柱形旋转的工件，其中两个光束是正交的。垂直于每个光束轴的工作位移可以从相关的双光电二极管的差信号检测。然后，可以使用两个正交的感测单元将工件的跳动轨迹绘制为Lisajous图。 ...更多信息 对于工件本身的圆度测量，采用了所谓的V形块法。两个传感单元可以看作是一个光学虚拟V形块，另一个传感单元可以看作是一个切向式位移传感器。结果表明，所开发的系统所测得的圆度轮廓与市售圆度仪所测得的圆度轮廓在每转波动率（UPR）上基本一致。对跳动轨迹中包含的形状误差进行了有效补偿。补偿前的跳动轨迹为方形轨迹，与仿真结果相似，当使用主要包含第三阶UPR振幅的小圆柱部分时。径向圆跳动值为1.24μn。利用测量的圆度曲线进行补偿后，方形圆角变圆，圆跳动值减小到0.71μm。因此，可以确认所开发的系统是跳动误差测量系统，其中圆柱形部分的圆度轮廓不影响跳动轨迹。少

An objective of our study is to develop an in-process measurement system which can evaluate both the roundness of turned cylindrical part and the rotational error of lathe spindle, Cylindrical parts to be measured are smaller than 2 mm in diameter and the target measurement accuracy of the system is the range of sub-micrometer. The Developed system is composed of measurement instrument, signal processing equipment and data analysis system. The measuring instrument of the developed system consists of three optical sensing units. Each unit has a parallel light beam and twin photo diodes to detect the asymmetrical beam power distribution, A cylindrically turned work is set within the crossing of the three light beams, where two of them are orthogonal. The work displacement perpendicular to each beam axis can be detected from the difference signal of the related twin photo diodes. Then the run-out locus of the work can be drawn as a Lisajous figure using the two orthogonal sensing units.As … More to the roundness measurement of the work itself, so-called V-block method was adopted. The two sensing units may be regarded as an optical virtual V-block and the remaining sensing unit as a tangential type displacement sensor.The measurement experiment was carried out with turned cylindrical part of 1mm in diameter at 300 rpm. As a result, the roundness profile by developed system is in rough agreement with the roundness profile by commercial instrument in undulation per revolution (UPR). The form error which was included in the run-out locus was effectively compensated. The run-out locus before the compensation was the square locus which was similar to simulation result, when small cylindrical part which mainly contains amplitude of 3rd UPR were used. Then, the value of radial circular run-out was 1.24μn. As a result of compensation using the measured roundness profile, the square corner became round, and the value of circular run-out decreased to 0.71μm. Consequently, it was able to be confirmed that the developed system was the run-out error measuring system in which the roundness profile of the cylindrical part did not influence in the run-out locus. Less