| 摘要 |
PURPOSE:To bore a through hole easily and precisely on a ribbed aluminum plate by providing a long cylindrical cutter and combining a refuse release means with the cutter. CONSTITUTION:A boring unit is mainly composed of a shaft 21, a cutter 22, and a refuse release means 23. A cutter fitting section 25 is provided below the shaft 21, and a fixed hole 29 for inserting and fitting a pilot drill 28 is provided on the cutter fitting section 25. The cutter 22 is composed of a head section 32, a trunk section 33, and a edge section 34. Furthermore, the refuse release means is composed of a pin holder 43 fitted to the shaft 21, a refuse releaser 37 with one end held and fixed by the pin holder 43 and with other end inserted into a pin hole 38 and kept free of moving back and forth against a hollow section 40, and a spring 35. Therefore, a through hole can be bored easily and precisely on a ribbed aluminum plate. |
