数控车削中心工件误差实时预报

数控车削中心工件误差实时预报(中文4600字,英文3900字Word+pdf)
第1部分：测量和鉴定
李小俚 制造工程系，香港城市大学，香港
本文分析了工件在加工旋转时的误差来源，其中主要来自机加工工具的几何误差，即热误差，该误差产生于机加工工件的切削力引起的刀具系统的偏转。一个简单和低成本的紧凑型测量系统相结合的灵敏的触摸传感器的工具（FTS-Q）产生了，并应用于测量工件表面.并且还介绍了一种识别工件误差的方法。工件的误差是由几何误差，热误差组成的，而切屑力误差根据每一步的测量结果是可以确定的。几何误差由建立在快速的基础上的两轴CNC车削中心模型测量，测量结果由坐标测量机（CMM）用FTS-Q的方法显示出来。实验结果表明，在工具旋转时，通过修改数控指令，这种几何误差可以得到补偿。
关键词：尺寸测量;错误辨识;几何误差;旋转

Real-Time Prediction of Workpiece Errors for a CNC Turning Centre, Part 1. Measurement and Identification

X. Li
Department of Manufacturing Engineering, City University of Hong Kong, Hong Kong
 This paper analyses the error sources of the workpiece in bar turning,  which  mainly  derive  from  the geometric  error  of machine  tools,  i.e. the  thermally  induced  error,  the error arising from machine–workpiece–tool system deflection induced by the cutting forces. A simple and low-cost compact measuring system combining a fine touch sensor and Q-setter of machine tools (FTSFQ) is developed, and applied to measure the work- piece dimensions. An identification method for workpiece errors is also presented. The workpiece errors which are composed of the geometric error, thermal error, and cutting force error can be identified according to the measurement results of each step. The model of the geometric error of a two-axis CNC turning centre is established rapidly based on the measurement results by using an FTSFQ setter and coordinate measuring machine (CMM). Experimental results show that the geometric error can be compensated by modified NC commands in bar turning.

Keywords: Dimension  measure;  Error  identification;  Geo- metric error; Turning