Development of an in-process inner diameter and roundness measuring instrument

最后，本文研制了一种基于三角法的内径和圆度在线测量仪，在基础实验中，利用一维光敏探测器（PSD）接收激光二极管发出的直射光束，研究了光束强度和照射位置对PSD输出、位置误差和重复测量标准偏差的影响。结果表明，当PSD的总输出电压v1 + v2在一定范围内时，可获得最小的标准偏差;当PSD的反向电压v R增大时，入射光束位置与输出光束位置之间的线性关系扩大。对于粗糙度较小的孔壁，也可以通过控制激光强度使PSD的总输出保持在最佳值来进行测量，并利用试制的色散型内径测量仪和表面粗糙度标准件作为被测对象，明确了被测对象的表面粗糙度与反射光束的强度和分布之间的关系。结果表明，随着表面粗糙度的增大，光强分布的宽度增大，光强分布形式随加工方向的不同而变化，因此，该方法有望应用于较大范围表面粗糙度的测量对象。

The present research finally intends to develop an in-process inner diameter and roundness measuring instrument, based on trigonometry.In the fundamental experiment, where 1-D photo sensitive detector (PSD) receives direct laser beam from a laser diode, the effects of beam intensity and radiated position on the PSD output, detected position error and standard deviation in repetitive measurement are investigated. The results indicate that minimum standard deviation can be obtained when the total output voltage v_1+v_2 of PSD takes a certain range of values and that linear relationship between incident beam position and output position spreads when the inverse voltage v_R to PSD increases. On the hole wall having considerably small roughness also, the measurement may be possible by controlling laser intensity so that the total PSD output may be maintained almost optimal.Using a dispersion-type inner diameter measuring instrument manufactured for trial and standard pieces of surface roughness as measured object, the relationship between the surface roughness of measured object and the intensity and distribution of reflective beam is made clear. The results show that the increase of surface roughness leads to the increase of width of intensity distribution and that the distribution form of intensity changes depending upon the orientation of machining.From the above mentioned, this method gives a promise to apply to the measured objects of considerably wide surface roughness.