Patent ID: 9676036
Date: 2017-06-13
CPC Classifications: B23B,B23Q,G05B,Y10T

Claim:
1. A polygon machining device comprising a main shaft gripping a workpiece, a tool spindle to which a polygon cutter is mounted, and a control unit configured to control the rotation of the main shaft and the tool spindle, being configured so as to carry out machining by a tool other than the polygon cutter on the workpiece after carrying out first polygon machining by the polygon cutter and to carry out second polygon machining by the polygon cutter after the machining, and carrying out machining on the workpiece by synchronously rotating the main shaft and the tool spindle to maintain a phase relationship between the main shaft and the tool spindle, wherein the control unit includes a synchronization ratio changing unit configured to make the phase relationship between the main shaft and the tool spindle constant at a predetermined fixed point by changing a synchronization ratio, at timing when a rotation position of the main shaft is located at the predetermined fixed point, between a synchronization ratio necessary for the first or second polygon machining and a second synchronization ratio in which the main shaft can rotate at a rotation speed necessary for the machining after the first polygon machining by rotating the tool spindle at a rotation speed not exceeding a maximum rotation speed, and the control unit is configured so as to carry out machining by synchronously rotating the main shaft and the tool spindle in the second ratio after the first polygon machining and to carry out the second polygon machining by changing the synchronous ratio after the machining after the first polygon machining.