Machine tool driving type retractable cutter and method for machining differential mechanism shell by using same

The invention discloses a machine tool driving type retractable cutter. The machine tool driving type retractable cutter comprises a power cutter tower and a power cutter seat, and is characterized inthat the inner part of the power cutter tower is connected with the outer part of the power cutter seat. The machine tool driving type retractable cutter is suitable for machining a mechanical part with an inner cavity being in a lantern shape, such as an automobile differential mechanism shell, wherein the size of the middle part of an inner cavity of the differential mechanism shell is about 70-110 mm, the size of hole parts at the two ends is about 24-32 mm, the cutter enters the inner cavity in a retracted state, and machines the inner cavity of the middle part after being automatically stretched, the key characteristic size items are completed in one process, the deviation caused by repeated clamping is reduced, and the size accuracy and the form and position tolerance accuracy are effectively guaranteed. 本发