| 摘要 |
The present invention relates to a method for forming a through-hole and an apparatus for forming a through-hole. The method for forming the through-hole comprises: a step of arranging a frame on a main body and fixing the frame with pressure in order to prevent the frame from movement or separation; a first drilling step of removing a part of the frame at a position corresponding to a position where the through-hole is formed in order to form a position indicating hole; a second drilling step of completely removing the inner face of the position indicating hole to form the through-hole penetrating the frame; and a third drilling step of forming a spiral thread along the inner face of the through-hole, wherein in the second drilling step, an end portion of a second drill for the second drilling step which touches the frame comes into face contact alongside of the surface of the frame, such that the opposite side of the frame which has the through-hole can be formed evenly. |
