抄録
It is necessary to machine holes of complicated shapes for building pipelines of hydraulic or pneumatic equipment. However, the degrees of freedom of machinable hole shapes are limited, since holes are generally fabricated by drilling. To enhance the degrees of freedom of these shapes, the authors have aimed to develop a device which can fabricate a hole on the inside wall of another hole by means of electrical discharge machining. Although it was proven that the last device developed has the ability to machine such a hole, it was found that this device has the weak point that the length of its machinable hole is short. To overcome the weak point, the improved device has been developed which is equipped with a supporting apparatus. The experimental results indicate that the improved device can make such a hole lengthened.
