放電加工による穴内面への細穴創成

抄録

Removal machining cannot generally fabricate a hole on the inside wall of another hole. That means, removal machining has the limitation for its fabricatable hole shape. The limitation affects designs of machines. In particular, the design of pipelines built in hydraulic equipment is affected. Many research groups have conducted the studies to overcome the limitation. Our research group had also developed the devices which can create such holes by means of electrical discharge machining in the previous studies. The previous studies had made it obvious that the devices can create a hole of 3.1 ~ 15.4 mm in inner diameter inside another hole of 21 mm. However, such a hole with an inner diameter less than 3.1 mm cannot be created. So, all the problems in designing pipelines built in hydraulic equipment are not solved. Therefore, this study has proposed a new device which can create a thin hole inside another hole. As a consequence, a hole of 1.7 mm / 0.6 mm in maximum / minimum inner diameter and of 26.0 mm in length could be created. This proves that the newly developed device has the ability to create thin holes on the inside walls of another holes.