Abstract: A gear grinding machine wherein a tooth alignment operation is performed prior to grinding, is equipped with a workpiece processing rotation shaft (22) which rotates a workpiece (W1) located at a workpiece processing position (P2); a workpiece swing device (30) whereby a tailstock (50) that holds the workpiece (W1) is swung between a workpiece replacement position (P1) and a workpiece processing position; a workpiece alignment rotation shaft (52) which rotates the workpiece held by the tailstock (50); and a tooth alignment sensor (43) that detects the rotation phase of the workpiece, which was rotated by the workpiece alignment rotation shaft. Before the workpiece held by the tailstock is placed at the workpiece processing position, the rotation of the workpiece alignment rotation shaft is controlled on the basis of the rotation phase detected, so that the workpiece will engage with a threaded grinding stone (16).

Abstract: Provided is a gear processing machine which has a simple configuration, and is capable of processing a gear with high accuracy. For this purpose, a gear grinding machine wherein a tooth alignment operation is performed prior to grinding, is equipped with a workpiece processing rotation shaft (22) which rotates a workpiece (W1) located at a workpiece processing position (P2); a workpiece swing device (30) whereby a tailstock (50) that holds the workpiece (W1) is swung between a workpiece replacement position (P1) and a workpiece processing position (P2); a workpiece alignment rotation shaft (52) which rotates the workpiece (W1) held by the tailstock (50); and a tooth alignment sensor (43) that detects the rotation phase of the workpiece (W1), which was rotated by the workpiece alignment rotation shaft (52).

Abstract: The index table includes a rotary table for setting a workpiece for a machine tool; a rotary table shaft fixedly provided on the rotary table; a driving motor mechanism, which is a driving source; and a planetary roller speed-reduction mechanism having a sun roller, which is a motor output shaft of the driving motor mechanism, a ring fixed to the speed-reduction mechanism, a plurality of planetary rollers arranged at equal angular intervals between the sun roller and the ring in a pressurized state, and a planetary roller harness that fixedly supports a plurality of planetary roller shafts pivotally supporting the planetary rollers in a rotatable manner and is fixedly provided coaxially with the rotary table shaft.

Abstract: There is provided a built-in type index table in which a power transmitting means scarcely has backlash and, at the same time, the space and cost can be saved. The index table includes a rotary table for setting a workpiece for a machine tool; a rotary table shaft fixedly provided on the rotary table; a driving motor mechanism, which is a driving source; and a planetary roller speed-reduction mechanism having a sun roller, which is a motor output shaft of the driving motor mechanism, a ring fixed to the speed-reduction mechanism, a plurality of planetary rollers arranged at equal angular intervals between the sun roller and the ring in a pressurized state, and a planetary roller harness that fixedly supports a plurality of planetary roller shafts pivotally supporting the planetary rollers in a rotatable manner and is fixedly provided coaxially with the rotary table shaft.