Broaching cutter

A broaching cutter for sequentially cutting a processing hole in a workpiece with a plurality of cutting blade stages provided side by side and for forming a plurality of internal teeth in the processing hole with a plurality of cutting blades arranged side by side in a circumferential direction of each of the cutting blade stages in such a manner that the internal teeth are arranged side by side in the circumferential direction, the broaching cutter comprising:

• cutting blade stages configured to cut the processing hole in such a manner that cutting locations of the cutting blades become deeper stepwise in a radial direction of the processing hole in the workpiece, and are also configured to include a plurality of initial cutting blade stages configured with initial cutting blades to cut formation portions to be tooth body portions of the internal teeth, a plurality of intermediate cutting blade stages configured to cut with intermediate cutting blades, the formation portions to be the tooth body portions more deeply than the initial cutting blade stages, and a plurality of final cutting blade stages configured to cut with final cutting blades, formation portions to be clearance portions extending from the tooth body portions toward an outer periphery in the radial direction, the initial cutting blade stages, the intermediate cutting blade stages, and the final cutting blade stages being sequentially arranged side by side such that cutting is performed in an order of the initial cutting blade stages, the intermediate cutting blade stages and the final cutting blade stages,
• a pair of distal end corners of each of the intermediate cutting blades in the intermediate cutting blade stages and a pair of distal end corners of each of the final cutting blades in the final cutting blade stages each have a curved shape or a chamfered shape larger than a curved shape or a chamfered shape of a pair of distal end corners of each of the initial cutting blades in the initial cutting blade stages, and
• a structure of the initial cutting blade stages is configured such that a cutting depth is smaller than a cutting depth of the intermediate cutting blade stages and the final cutting blade stages.