A Precision CNC Turn-Mill Machining Center with Gear Hobbing Capability
With ever increased demand for reduced sizes and increased complexity and accuracy, traditional machine tools have become ineffective for machining miniature components. Typical examples include dental implants, the parts used in mechanical watch movement, and the parts used in medical endoscope. With complex geometry and tight tolerance, few machine tools are capable of making them. This paper introduces our PC-based CNC Turn-Mill Machining Center. It has 5 axes, an automatic bar feeder, an automatic part collection tray, and a tool changer. In particularly, it has a special synchronization control algorithm that gives not only higher accuracy but also ease of use. In addition, to improve the accuracy, the software based volumetric error compensation system is implemented. Based on the experiment testing, the machining error is ± 3 µm in turning, ± 7 µm in milling and the maximum profile error is less than ± 7.5 µm in gear hobbing.