超精密数控机床B旋转轴的可量化对刀方法

Tool alignment on the B axis rotary table of an ultra-precision lathe machine

为了提高超精密数控机床旋转B轴的对刀精度和效率,基于3点坐标确定圆心的原理,提出了一种可量化的B旋转轴对刀方法。采用一种非接触式图像识别方式进行精确对刀,可避免对刀过程中金刚石刀具的破损,同时解决刀尖视场与机床坐标不一致的问题。利用Fresnel透镜模具加工实验验证了对刀精度,并通过激光显微镜检测沟槽里尖角的圆弧半径来确定对刀误差。实验结果表明:该可量化对刀方法的对刀误差为0.8μm,该误差在预先计算的理论误差1μm范围里。该对刀方法适用于超精密切削加工,且对刀的精度可以预测和控制。

The accuracy and efficiency of tool alignment on the B axis rotary table of an ultra-precision lathe machine are improved using a method to find the circle center from three points. The image recog- nition tool setting technique avoids the effect of wear on a single point diamond cutting tool and problems when the tool tip is outside the image processing field and different coordinate systems are solved in the image processing and the lathe machine. The turning of a Fresnel lens mold is used to verify the precision of the image recogni- tion tool alignment method on the B axis rotary table with the tool a- lignment error obtained by detecting the circle radius of the sharp corner of the V shaped grooves. The tool alignment error is 0.8 μm as measured by a laser microscope, which is in the theoretical range of 1 μm calculated in advance. The results show that the method is suitable for ultra-precision cutting with predictable and controllable tool alignment precision.