JPS55150921A - Electric discharge machining method - Google Patents

Abstract

PURPOSE:To both smoothly machine roll end parts and flatly maintain electrode ends when finished an electric discharge machining work, by giving a reciprocating feed motion to the electrode in such a manner that the electrode is allowed to move in and out a fine amount of distance at the roll end part. CONSTITUTION:Left and right auxiliary heads Hs are transversely fed in the direction detaching firstly from roll end parts then in the reverse direction when electrodes 2 come out to a position a fine amount of distance away from substantially end parts 31 again in the reverse direction when fed to a position with a fine amount of distance inside from the roll end parts. Such operations as said in the above are repeated to perform the reciprocating transverse feed movement till depths of machining in the roll end parts become slightly larger than those in the roll central parts to be machined by a main head HM and finish the machining work at positions with the electrodes 2 inside the roll end parts. Because of machining the roll end parts in such a manner as in the above, the electrodes 2 of the auxiliary heads are worked to be shaped, flatly maintained in their end parts and able to be used in the state as they are when the next roll is machined.