Patent ID: 8777823

Claim:
An automatic tool changer comprising: a tool-changing shaft configured to turn a tool-changing arm, the tool-changing arm being configured to turn so as to move forward and backward in a direction of the tool-changing shaft and to change tools in a tool spindle in a tool-changing position, and an arm drive device configured to turn in the direction of the tool-changing shaft and to move the tool-changing arm, wherein the arm drive device is configured to execute a parallel operation comprising: a turning operation so as to turn the tool-changing arm by 180°, and a forward and backward moving operation so as to move the tool-changing arm forward and backward in a tool inserting direction to permit the tools to be inserted in and removed from the tool spindle, wherein at least part of the turning operation and at least part of the forward and backward moving operation are configured to be simultaneously executed in parallel, and wherein when the tool-changing arm is moved forward and backward in the tool inserting direction to remove the tools, the tool-changing arm is configured to be turned by a predetermined amount of movement in a direction opposite to a positive direction in which the tool-changing arm is turned by 180°, and thereafter turned in the positive direction, and wherein the arm drive device comprises a cam mechanism including a roller-gear cam configured to be rotated by an electric motor.