大直径在线高精度测量不确定度分析  

Uncertainty Analysis of On-line Measuring of Large Diameters

作　　者：赵前程[1] 陆长友[1] 罗晓莉[1] 

机构地区：[1]湖南科技大学机械设备健康维护省重点实验室,湘潭411201

出　　处：《机械科学与技术》2008年第9期1247-1251,共5页Mechanical Science and Technology for Aerospace Engineering

基　　金：湖南省教育厅青年项目(07B020);湖南省科技厅一般项目(2007FJ4143)资助

摘　　要：讨论了基于"弓高弦长法"测量原理,由3只精密激光位移传感器组成的大直径非接触在线测量装置的测量不确定度。针对被测大轴的尺寸,选择固定的弦长;基于两标准尺寸的外圆盘进行弦长参数的标定;通过3只传感器的对称布置、相对测量、多次测量求平均值等措施,简化了测量装置的结构、方便了标定和测量过程、提高了直径测量精度。对于直径500 mm^510 mm的大轴,当其圆度误差不超过30μm、3只传感器光线的不平行度误差小于0.5°、上下传感器的不对称小于1 mm、标定和测量时中间传感器光线不对中误差小于1 mm时,直径测量结果的不确定度小于3μm。An apparatus, mainly made of 3 displacement sensors, for on-line measuring of large diameter from chord length and bow altitude is designed, and the measuring uncertainty is studied in detail. The chord length, being calibrated with two standard circles, is selected and fixed for matching with the dimension of measured large diameter. Techniques such as symmetrical layout of three sensors, relative measuring method, and averaging of the measuring results, are presented. Therefore, the structure of measurement apparatus, the processes of calibration and measurement are simplified, while the measuring precision is improved. Under certain conditions, diameter measurement uncertainty is less than 3μm for a shaft with diameter of 500 mm - 510 mm.

关 键 词：大直径 在线测量 相对测量 不确定度 

分 类 号：TB92[一般工业技术—计量学]