| 摘要 |
PURPOSE:To reduce errors in indexing of an electrode to make it possible to index the electrode with a high degree of accuracy, by providing a device for detecting the reference position of a worm wheel, in an electric discharge machining device. CONSTITUTION:A magnetic generating member 10a in a positional detector 40 is attached to a worm wheel 9, and a detecting head 40b in the positional detector 40 is attached to a head 8 so that the member 10a and the head 40b are opposed to each other with a slight gap being held therebetween. The reference position of the wheel 6 is detected by an original point confirming detector which is not shown, and which delivers a signal, and an indexing angle detector 34 delivers a reference point signal. A change of the position of meshing between worm and wheel when the original point after stopping of high speed rotation of a spindle 4 is returned to the original point before the high speed rotation, is compensated by the above-mentioned signal. |
