DEVELOPMENT OF CURVED HOLE MACHINING METHOD – SIZE REDUCTION OF HOLE DIAMETER –

ABSTRACT This study deals with a diameter reduction of curved holes that can be machined by the method developed by the authors. In order to improve the productivity of molding, it is necessary to increase the efficiency of the cooling stage in a molding cycle. It depends on the shape and the arrangement of water channels, i.e., pipelines built in molds. However, water channels consist of a series of straight holes due to the fabrication by drilling. Accordingly, it is strongly required to develop a machining method of curved holes since curved water channels are desirable. To meet the requirement, the device has been developed, which can make an electrode move along a curved trajectory with electrical discharge machining. The device can fabricate curved holes. However, the fabricated curved holes have a problem that their diameter is too large to employ them as a water channel. In the study, thus, the size reduction of the curved holes is tried by improving the electrode and its peripheral parts.