Development of Forming System for Micro Medical Tool Using Oblique Mill

本研究的目的是开发具有复杂和详细形状的医疗零件生成系统。通常，立铣刀用于制造这种形状。特别是，商用立铣刀的最小尺寸为0.1 mm，在研究水平上为0.06。因此，我提出了斜切式磨煤机。该工具具有非常简单的形状，通过对角线切割圆柱形工具材料而制成。这种刀具的一个缺点是切割能力差。因此，本研究对最佳的切割条件进行了研究。通过对切屑现象的CCD型显微镜观察，发现由于材料塑性变形，切屑去除率低，导致切屑切割能力差。从切屑阻力和切屑去除的角度来看，最佳倾角为30度左右。对加工表面的粗糙度进行了实验和理论分析。斜角越小，进给速度越小，表面粗糙度越低。考虑了防止切削面产生大量毛刺的对策。众所周知，通过优化进给速度，重复切割和刀具路径毛刺大大减少。开发了一种新型的微切削系统，证实了15-25μm斜切机对医用钳等微槽和三维形状的加工是有效的。直径0.2 mm的普通微型立铣刀可以辅助上述制造。

The aim of this study is development of system to create medical parts with complicated and detailed shapes. Generally, the end mill is used for fabricating such shapes. In particular, The minimum size of commercial end-mills is 0.1 mm, and 0.06 at the research level. I thus proposed the oblique-cut mill. This tool has a very simple shape made by diagonally cutting a cylindrical tool material. One drawback of this tool is its poor cutting ability. In this study, the optimum cutting conditions were therefore investigated.1. As the result of observation of cutting phenomena by CCD- type microscope, the poor cutting ability due to plastic deformation of material and low chip removal rate are known.2. An optimum oblique angle is about 30 degree from the point of view or cutting resistance and chip removal.3. The roughness of cut surface is experimentally and theoretically analyzed. Surface roughness becomes lower in case of small oblique angle and small feed rate applied.4. The counter plan preventing from large burr generated at cut surface is considered. It is known that by optimizing feed rate, repeated cutting and tool path burr drastically diminished.5. New micro cutting system is developed and it was confirmed that the 15-25 μm oblique-cut mill is effective for fabricating micro groove and three-dimensional shapes such as medical forceps. An ordinary miniature end mill of 0.2 mm diameter can assist above fabrication.