航空工业对数控机床的需求具有高精度、复合及多轴联动等特点。数控机床的时变误差影响航空零件批量加工时的精度稳定性。对此,基于传热机理的时变误差模型对航发企业的卧式加工中心进给轴进行时变误差补偿。对卧式加工中心进给轴时变误差进行了测试,并对模型中的热特性参数进行了辨识。基于TCP/IP协议建立时变误差补偿器与数控系统之间的通讯,通过机床坐标原点偏置方式实现时变误差实时补偿。最后,在某航发企业卧式加工中心HAAS HS-1RP上开展了补偿效果的验证试验。试验结果表明,补偿后进给轴热致时变误差可以减少85.2%,大幅提高了机床的精度稳定性。
The demand for CNC machine tools in aviation industry is characterized by high accuracy, compound and multi-axis link-age. The accuracy stability of the aeronautical parts machined by batch-process is affected by time-varying error of CNC machine tools. Therefore, the time-varying error of feed axes for horizontal machining center of aero engine enterprises is compensated in real-time based on mechanism-driven time-varying error model. The time-varying error of feed axes is measured, and the thermal characteristic parameters in the model are identified. The compensator of time-varying error communicates with CNC system based on TCP/IP protocol. The method of machine tool coordinate origin offset was used to compensate the time-varying error. Finally, the test verification is implemented on a horizontal machine tool, the HAAS HS-1RP. The results show that the time-varying error of feed axis can be reduced by 85.2% with error compensation, and the accuracy stability of machine tool is improved greatly.
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