A tool changing device for tool systems in which a tool head and a tool holder are connected with one another by means of an automatic clamping mechanism which includes an integrated clamping screw. The tool changing device includes a lifting carriage which is movable on several axes and a rotatably mounted, motor driven pivot arm which is mounted on the lifting carriage. The pivot arm has a free end which is equipped with a gripper holder having at least four tool locations and an integrated clamping shaft. Both ends of the clamping shaft are provided with profiles which permit transfer of torques. The clamping shaft can be moved axially in such a manner that it can be coupled with the clamping screw of a tool holder either from the left or from the right.