Tooth Flank Machining Device and Tooth Flank Machining Method

A tooth flank machining method for grinding, using a tooth flank machining device, a tooth flank that forms a tooth space of a workpiece gear,

• the tooth flank machining device including:
• a first motor configured to rotate a grinding tool including a tool tooth portion having a thickness smaller than a width of the tooth space;
• a predetermined sensor configured to output a detection signal corresponding to a load of the first motor;
• a second motor configured to rotate the workpiece gear;
• and
• a control device configured to control the second motor,
• the tooth flank machining method comprising:
• causing the control device to acquire the detection signal;
• and
• causing the control device to control the second motor based on the detection signal to adjust a lead angle of the workpiece gear relative to the grinding tool in a manner so that the load in a case where the tooth flank is ground by the tool tooth portion of the grinding tool during rotation falls within an allowable range determined in advance.