A gear manufacturing machine for which a machining tool detachably attached to a tool spindle is exchanged by means of an automatic tool changer, wherein the automatic tool changer is provided with: tool holding means for detachably holding a machining tool to be exchanged; moving means for moving the tool holding means in a direction parallel to the axial direction of the tool spindle; and rotating means for rotating the tool holding means.

A tool magazine device includes a rail that is annularly formed and that has a separation section at a part in a circumferential direction of the rail and a holding ring that is arranged coaxially with the rail and that is rotated by a driving motor. The holding ring is provided with a plurality of holding sections that are open in an axial direction of the holding ring. The holding sections are arranged in the circumferential direction of the holding ring. A tool pot is held to be insertable into and extractable from each holding section. A conveyance unit sends out the tool pot placed in the holding section to an exchange position and sends the tool pot into the holding section from the exchange position. A roller supported by each tool pot rolls on the rail in response to the rotation of the holding ring.

A tool change rotary position determining device includes: a turret rotation controller configured to control a turning motor so as to turn a turret clockwise and counterclockwise in a state where a tool holder of a tool gripped by a specific grip on the turret is inserted in an attachment hole of a spindle; and a tool change rotary position determining unit configured to determine a tool change rotary position of the turret when the tool is transferred between the specific grip and the spindle to be attached to and removed from the spindle, based on the load torques and the rotary positions of the turning motor when the turret is turned clockwise and counterclockwise.

A tool magazine (40) is able to move among a machining position where a tool (2) attached to a spindle (30) machines a workpiece, a tool exchange position where the tool (2) attached to the spindle (30) is exchanged, and a retreat position where an automated workpiece carrying device is not disturbed in placing or removing of the workpiece with respect to a workpiece placing part (20). The workpiece is placed on the workpiece placing part (20) from above or removed upward from the workpiece placing part (20) by the automated workpiece carrying device.

The invention relates to a machine tool cocoon (10) for receiving a workpiece, having a base element (18) on which the workpiece can be disposed, wherein the base element (18) comprises at least one receptacle (47) for receiving and fixing a workpiece (40), and a support device (11) separably connected to the base element (18). The machine tool cocoon (10) can be positioned on a tool position of a tool changing system by means of the support device (11). The invention further relates to a method and a computer program.