Gear machining device and gear machining method

A gear machining device comprising:

• a machining tool to be used for machining a gear, the machining tool having a rotation axis inclined with respect to a rotation axis of a workpiece, the machining tool being fed relatively in the direction of the rotation axis of the workpiece while being rotated synchronously with the workpiece, wherein
• a gear tooth includes a side surface including a plurality of subordinate tooth flanks having different torsion angles from a main tooth flank respectively thereon on one side and the other side of the workpiece in the direction of the rotation axis,
• the machining tool includes:
• a first cutting blade having a rake face facing one side in the direction of the rotation axis of the machining tool;
• and furthermore a second cutting blade having a rake face facing the other side in the direction of the rotation axis of the machining tool,
• the first cutting blade is used for machining the subordinate tooth flanks provided on the other side of the workpiece in the direction of the rotation axis by moving the machining tool relatively with respect to the workpiece to the other side of the workpiece in the direction of the rotation axis, and
• the second cutting blade is used for machining the subordinate tooth flanks provided on the one side of the workpiece in the direction of the rotation axis by moving the machining tool relatively with respect to the workpiece to the one side of the workpiece in the direction of the rotation axis.

A gear machining method for machining a gear by means of a machining tool,

• a gear tooth includes a side surface having a first tooth flank and a second tooth flank having a torsion angle different from the first tooth flank,
• the machining tool includes a cutting blade, and the cutting blade has a blade trace having a torsion angle determined based on the torsion angle of the second tooth flank and an intersection angle between the rotation axis of the workpiece and the rotation axis of the machining tool so as to allow the second tooth flank to be machined on the pre-machined first tooth flank,
• the gear machining method comprising:
• inclining the rotation axis of the machining tool with respect to the rotation axis of the workpiece, and
• machining the second tooth flank by feeding the machining tool relatively with respect to the workpiece in the direction of the rotation axis while rotating synchronously with the workpiece.

A gear machining method for cutting a gear by means of the machining tool having a rotation axis inclined with respect to a rotation axis of a workpiece,

• a gear tooth includes a side surface including a plurality of subordinate tooth flanks having different torsion angles from a main tooth flank respectively on one side and the other side of the workpiece in the direction of the rotation axis,
• the machining tool includes:
• a first cutting blade having a rake face facing one side in the direction of the rotation axis of the machining tool;
• and furthermore a second cutting blade having a rake face facing the other side in the direction of the rotation axis of the machining tool,
• the gear machining method comprising:
• a first step of machining the subordinate tooth flanks provided on the other side of the workpiece in the direction of the rotation axis with the first cutting blade by moving the machining tool in the direction of the rotation axis of the workpiece on the other side of the workpiece in the direction of the rotation axis relatively with respect to the workpiece while rotating the machining tool synchronously with the workpiece;
• and
• a second step of machining the subordinate tooth flanks provided on the one side of the workpiece in the direction of the rotation axis with the second cutting blade by moving the machining tool in the direction of the rotation axis of the workpiece on the one side of the workpiece in the direction of the rotation axis relatively with respect to the workpiece while rotating the machining tool synchronously with the workpiece.