PURPOSE: To eliminate the quality accident by erroneous decision and to facilitate the exchange of various defective elements of the date wheel rotating mechanism by providing the rotating mechanism which rotates the date wheel via a winding stem and a sensor which detects the rotation of the date wheel.

CONSTITUTION: The movement in which the date wheel is assembled is fixed to a pallet 1 and is transported in the system within the stage of an automated assembly line system for a series of movements. The movement is fixed to the pallet 1 and is transported at this time. The movement is in a time adjustment state and the pallet 1 is fixed by the arrowmarked movement of vertical 3. The revolutions of a motor 5 are simultaneously transmitted by a cylinder 6 to rotate the winding stem 2 as the cylinder moves in an arrow (b) direction and comes into contact with the winding stem 2. The date wheel is thereby jumped and rotated and this movement is detected by a rotation detecting sensor 4. The detection of the date wheel rotating mechanism which is heretofore carried out by man and by a visual inspection is automatically executed in this way.