整体叶轮在分度装置装夹下的CMM测量方法研究
Research on Measuring Method of Monolithic Impeller with Dividing Apparatus Via CMM

利用三坐标测量机测量整体叶轮，需要分度装置来满足各个叶片的测量。由于各种误差特别是安装误差的影响，会引起整体叶轮中心轴与分度装置的中心轴不重合从而产生运动偏心，使得测头无法顺利接触叶片并影响整体叶轮叶片型面的检测精度。提出两种测量策略：分次独立坐标系测量法和统一坐标系测量法。前者在每次分度后都重新建立坐标系，减少分度过程中造成的误差；后者只建立一次坐标系，通过计算叶轮中心与分度装置中心间的偏心来进行误差补偿。
To measure the monolithic impeller on coordinate measuring machine(CMM), the dividing apparatus is needed for sampling individual blades. The installation eccentricity between the monolithic impeller and the dividing apparatus will cause eccentric motion, which affects the contact between the measuring head and the blades. Even worse, it reduces the detection accuracy of blade surface. Two measurement strategies are proposed, namely independent coordinate measurement and unified coordinate measurement. The former re-establishes the coordinate system after each dividing operation to lower the eccentricity-induced error. The latter establishes coordinate system only once, while achieves error compensation with calculating the eccentricity between the monolithic impeller and the dividing apparatus