Sheet Processing Apparatus Switchback Transport Guide
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sheet processing apparatuses face issues with proper switchback-transport of sheets during inward three-fold processing, leading to potential damage from turn-up preventing members and curled sheet end portions not being properly guided back to the stacker.
Innovation Solution
A sheet processing apparatus with a transport path, rotating body pair for folding, a folding blade, and a press member supported by a support portion to guide and press the sheet end portions correctly during switchback-transport, ensuring they are aligned and directed properly for folding and stacking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a turn-up preventing member is provided swingably in a sheet path to prevent turn-up during switchback-transport, then turn-up of sheet end portion is prevented, but the member may collide with the sheet end at an angle near perpendicular causing damage
Solution Approach 1:
Instead of preventing turn-up by blocking the sheet end from above (which causes perpendicular collision), the invention allows the sheet end to turn up naturally and then guides it back down using a guide face. This inverts the approach from active prevention to passive guidance, eliminating the collision hazard while achieving the same turn-up prevention effect.
Solution Approach 2:
The guide face acts as an intermediary between the turn-up preventing member and the sheet end. Rather than direct contact between the member and sheet end, the guide face mediates the interaction, providing a controlled surface that guides the sheet end back to the proper position without causing damage.
2Reliability
If the sheet end portion is curled and deformed to the folding roller side, then the turn-up preventing member pushes the curled end portion to the folding roller side, but it is not possible to properly switchback-transport the sheet
Solution Approach 1:
The guide face is positioned and oriented to preliminarily guide the sheet end portion before it reaches the turn-up preventing member. This preliminary guidance action prevents the sheet end from curling to the folding roller side in the first place, ensuring proper switchback-transport without needing to push the curled portion.
Solution Approach 2:
The invention replaces the mechanical pushing action (which fails when sheet is curled) with a geometric guidance system using the guide face. The guide face's orientation and position create a mechanical constraint that naturally directs the sheet end to the correct path without active pushing, even when curled.
Data Source
AI summary
A sheet processing apparatus includes a transport path to guide a sheet transported in a predetermined transport direction, a rotating body pair capable of transporting the sheet in a first direction for nipping the sheet transported to the transport path thereby drawing the sheet to perform folding processing, and in a second direction for switching back the sheet to return to one direction side in the transport direction, a press member for pressing the sheet folded by the rotating body pair in the second direction, and a support portion for supporting the press member, where the support portion is disposed on the side opposite to the rotating body pair with the transport path therebetween and on the other direction side opposite to the one direction side in the transport direction with a nip line for connecting between the nip portion and a front end portion of the folding blade therebetween.