Combined gear cutting apparatus

A combined gear cutting apparatus comprising:

• a workpiece drive portion configured to hold and rotate a workpiece which serves as a processing object;
• a first processing portion holding a first tool which serves as a gear cutting tool and moving the first tool to a processing position for processing the workpiece in a state where the first tool rotates synchronously with the workpiece drive portion;
• a second processing portion holding a second tool which serves as a cutting tool different from the gear cutting tool and moving the second tool to a processing position for processing the workpiece in a state where the second tool is synchronized with the workpiece drive portion;
• and
• a control portion controlling driving operations of the workpiece drive portion, the first processing portion and the second processing portion,
• the control portion including a storage portion which stores:
• (i) workpiece information indicating a configuration of the workpiece relative to a workpiece reference point of the workpiece drive portion, which configuration is the configuration before first processing is performed by the first tool, (ii) first tool information specifying a position of a cutting blade of the first tool relative to a first reference point of the first processing portion, (iii) second tool information specifying a position of a cutting blade of the second tool relative to a second reference point of the second processing portion, and (iv) relative position information specifying a relative position between the workpiece reference point, the first reference point and the second reference point,
• the control portion including a tooth groove configuration calculation portion calculating tooth groove configuration information of the workpiece relative to the workpiece reference point based on the first tool information, based on the workpiece information, and based on the relative position information obtained when the first processing by the first tool is completed,
• the second tool being configured to move to a start position of second processing for the workpiece based on the tooth groove configuration information, based on the second tool information and based on the relative position information.