微細表面形状の塑性加工による情報伝達機能の創成

―円錐ピンによる2次元バーコードの逐次マイクロ塑性加工―

抄録

Microforming of controlled cavities over workpiece surfaces is a promising application of metal forming although it is not yet popular. Metallic surfaces can thus have the function of reliable and durable information transmission that can be used, for example, in quality control, recycling and the disposal of industrial parts. However, usually metal forming requires a set of tools that is suitable for producing geometrically fixed parts and has some difficulties adapting to various geometries corresponding to various information to be transmitted. In this paper, numerals and characters are converted into two-dimensional bar code symbols of the Data Matrix and QR Code by a PC software. The symbol images are exported to a PC-controlled dot impact machine and then all the white cells of the symbol are dotted onto a metal sample, for example a polished stainless steel plate, by a cone-shaped dot impact pin. The pitch of dots is fixed at 0.12 mm and the diameters of dots range from 28 to 68 μm depending on the setup of the machine. Dotted marks of even three hundred characters are rapidly decoded by a PC-controlled optical system that supports direct marking and is equipped with a CCD macrolens and a ring light guide. Further miniaturization seems possible owing to the flexibility of the measuring system in terms of cavity size, illumination and optical magnification.