链式刀库运动精度检测方法研究

Research on detection method of dynamic accuracy of chain tool magazine

刀库及自动换刀装置（ATC）的主要功能是存储刀具和交换刀具,其性能特别是刀库的运动精度影响着大型数控机床或加工中心是否能迅速、准确地完成换刀,是影响机床可靠性的关键因素。为研究链式刀库的性能尤其是刀柄的运动精度,主要包括每个刀位及整体的定位精度和重复定位精度,提出一种基于激光位移传感器和标准刀柄补偿的链式刀库运动精度检测方法。针对链式刀库顺时针和逆时针两种方向的运动,设计合适的工装并利用两个激光位移传感器间接测量得到刀柄装夹圆的圆心。通过将基准坐标下所测的标准刀柄装夹圆圆心坐标对所测的模拟刀柄装夹圆圆心坐标进行补偿,得到参考坐标系下模拟刀柄装夹圆圆心坐标,从而确定链式刀库每个刀位和整体的运动精度,估计所测链式刀库的故障阈值范围,为链式刀库故障预测提供了重要依据。

The main function of the tool magazine and automatic tool changer（ATC） is to store tools and switching tools. Its performance, especially the dynamic accuracy of the tool magazine, influences whether large CNC machine tools or machining centers can complete the tool change quickly and accurately, which is the key factor of machine reliability. The positioning accuracy and repetitive positioning accuracy of each tool position and the whole are two main performance of the chain tool magazine, especially the dynamic accuracy of the tool holder. To improve the performance, a new method based on the laser displacement sensor and the standard tool holder compensations proposed. For the clockwise or counterclockwise direction of the chain tool magazine, suitable tooling is designed and the center of the tool holder clamping circle is indirectly measured with two laser displacement sensors. With the center of the clamping circle of the standard tool holder in the reference coordinates, the center of the clamping circle of the simulated tool holder is compensated, and the center of the clamping circle of the simulated tool holder is obtained in reference coordinate system. Then, the dynamic accuracy of each tool position and the whole of the tool magazine is determined, and the whole fault threshold range of the tested chain tool magazine is estimated, which provides an important basis for chain magazine failure prediction.