Sheet Conveyance Skew Detection and Mixed Stacking Mode Control

The patent applies local quality by making the skew detection function conditional rather than universal. The control unit activates skew detection only when the different-width mixed stacking mode is not selected, thereby adapting the detection behavior to the specific operating mode. This resolves the contradiction by ensuring high reliability for bound document detection in normal mode while avoiding false detections in different-width mode through conditional deactivation of the detection function.

The patent applies preliminary action by proactively displaying the mode setting screen immediately when skew is detected, rather than requiring the user to manually navigate through multiple menus later. The control unit detects skew, automatically determines that different-width documents may be the cause, and preemptively presents the solution (mode setting screen) to the user. This resolves the contradiction by enabling different-width handling while minimizing operational burden through timely, context-aware interface presentation.

The patent applies the extraction principle by isolating the mode setting function into a dedicated, easily accessible screen that is directly displayed in response to skew detection. Instead of burying the mode setting option within multiple nested menu structures, the control unit extracts the essential function (mode selection) and presents it through a simplified interface. This resolves the contradiction by maintaining full configuration capability while dramatically improving operational efficiency through direct access.