| 摘要 |
PURPOSE:To make it possible to maintain the primarily high machinability of a grindstone by dressing the grindstone for machining at the inner periphery by means of an electrode for dressing without interrupting the machining of a workpiece. CONSTITUTION:A grindstone 1 for machining is a doughnut shaped disk of which center is opened. With a conductive raw material exposed, a conductive belt 2 is formed in the inner periphery of a machined hole. With a specified machining liquid being supplied from a nozzle 8 to the portion of contact of the surface of the inner periphery of the grindstone 1 and a workpiece W by rotating the grindstone 1, a power source for machining is impressed to make the two approach each other until they contact. While the workpiece W is machined, and the specified machining liquid is supplied between the inner peripheral surface of the grindstone 1 rotating and a grindstone 6 for dressing at the position of approaching or contacting with the grindstone 1, a power source for dressing is connected. |
