A shaving processing method and apparatus for a gear are provided which reduce a load at the time of processing a tooth surface, thereby reducing a transmission error of the gear. Embodiments include a method for finishing the tooth surface of the gear in a state where the gear and a shaving cutter are engaged with each other and the shaving cutter is rotated. The gear has a pair of end surfaces facing each other in the tooth width direction. A first shaving step of processing the tooth surface is performed so that a processing region gradually expands from one end surface of the pair of end surfaces toward the other end surface, and a second shaving step of processing the tooth surface is performed so that a processing region gradually expands from the other end surface of the pair of end surfaces toward the one end surface.

A shaving processing method and apparatus for a gear are provided which reduce a load at the time of processing a tooth surface, thereby reducing a transmission error of the gear. Embodiments include a method for finishing the tooth surface of the gear in a state where the gear and a shaving cutter are engaged with each other and the shaving cutter is rotated. The gear has a pair of end surfaces facing each other in the tooth width direction. A first shaving step of processing the tooth surface is performed so that a processing region gradually expands from one end surface of the pair of end surfaces toward the other end surface, and a second shaving step of processing the tooth surface is performed so that a processing region gradually expands from the other end surface of the pair of end surfaces toward the one end surface.

To provide a gear machining device and a gear machining method which achieve machining of tooth flanks having different torsion angles with high degree of accuracy. In a gear machining device, a side surface of a tooth of a gear includes a first tooth flank and a second tooth flank having a different torsion angle from the first tooth flank, a cutting blade of a machining tool has a blade traces having a torsion angle determined based on a torsion angle of the second tooth flank and an intersection angle between a rotation axis of a workpiece and a rotation axis of the machining tool so as to allow the second tooth flank to be machined on the pre-machined first tooth flank.

This gear cutting machine, which is equipped with a cutter (15), a cutter spindle motor (11) that causes, via a crank mechanism (13) and a cutter spindle (16), the cutter (15) perform a stroke operation, and a motor control unit (10) that controls the rotation angle of the cutter spindle motor (11), is provided with a relieving spindle motor (12) that causes the cutter (15) to move in the direction of a relieving spindle via a link mechanism (four-joint link mechanism (14)). The motor control unit (10) controls the rotation angle of the relieving spindle motor (12) on the basis of the rotation angle of the cutter spindle motor (11). Consequently, a gear cutting machine that accurately controls the relieving operation in accordance with a desired shape, such as crowning and tapering of a gear to be cut can be provided.

The inventive device includes a work supporting portion for supporting a work rotatably about a first axis, a cutter supporting portion for supporting a cutter rotatably about a second axis different from the first axis and a moving portion for moving the cutter along a reference line extending through the first axis. The second axis is slanted relative to a reference plane oriented perpendicular to the first axis and a blade edge of the cutter is caused to come into contact with the work at an offset position offset from the reference line. The work and the cutter are driven in synchronism and the cutter is moved along the reference line.