ROUND SCREW MACHINING METHOD

摘要

When a round screw is machined with a tool (TL) having a radius smaller than the radius r of arc of a screw (RST), data necessary for determining (i) a tool, passage pattern of a round threading cycle (PLi) and (ii) a cycle start point (Pi) of each round threading cycle are added to the NC instruction data of the round threading cycle and the results are instructed, and the cycle start point (Pi) of the round threading cycle (PLi) is determined along the arc shape of the round screw by use of the data described above. Machining of the round screw is carried out by executing the repetition of the screw threading cycles while shifting sequentially a cycle start point along the arc shape.