A gear machining apparatus includes a machining tool having a plurality of protruding tool edges on an outer periphery of the machining tool, and driving apparatuses that form a tooth on a work piece by rotating the machining tool around a central axis thereof, rotating the work piece W around a central axis thereof, and moving the machining tool relative to the work piece. Radial outer faces of the protruding tool edges form multiple steps that are parallel to the central axis of the machining tool such that the diameter of the machining tool increases in a stepwise manner from a tool leading end toward a tool base end of the machining tool.

The disclosure relates to column module, more particularly it is relating to a multi-axis column module. The multi axis column module comprising a support structure of predetermined shape; at least one Automatic Tool Changer [ATC] consisting a tool magazine ensconcing a plurality of tools mounted onto the support structure, a drive unit with a spindle connected to said tool magazine, a gripper arm connected to the spindle of the drive unit; and at least one ram housing having at least one spindle at center and is mounted over the support structure. The disclosure also provides for a method of swapping tools in the multi axis column nodule and method of assembling the multi axis column module.

A gear machining apparatus includes a machining tool having a plurality of protruding tool edges on an outer periphery of the machining tool, and driving apparatuses that form a tooth on a work piece by rotating the machining tool around a central axis thereof, rotating the work piece W around a central axis thereof, and moving the machining tool relative to the work piece. Radial outer faces of the protruding tool edges form multiple steps that are parallel to the central axis of the machining tool such that the diameter of the machining tool increases in a stepwise manner from a tool leading end toward a tool base end of the machining tool.