(1) After grinding the teeth of the gear shaft, the locating groove is machined as shown in the figure.
(2) The angular position error of the center line and the center line of the groove is not more than 0.005 degrees for the machining of the locating groove. The position error of the center line of the reference teeth and the center line of the groove is calculated according to the diameter of the indexing circle of 360 mm. The position error of the center line of the reference teeth and the center line of the groove is not more than 0.015 mm
(3) Five-axle CNC machining center with on-line detection device should be selected for positioning groove. Fixtures should be used to position the workpiece correctly. Then, the probe of on-line detection device should be operated to find the center position (angular position) of the reference teeth and record it. Milling cutter should be used to process the dimensions of the positioning groove according to the recorded angular position and mark it on the reference teeth.
(4) The positioning groove machined needs to measure whether the angular position is correct or not. It can be measured online on the machine tool or offline on the three coordinates.