Movable Discharge Tray for Curl-Resistant Sheet Alignment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing sheet post-processing apparatuses face issues with proper sheet discharge due to curl interference, where curled sheets can cause problems such as rolling, buckling, and erroneous detection by curl sensors, leading to improper alignment and discharge.

Innovation Solution

A sheet post-processing apparatus with a movable discharge tray and a control unit that synchronizes the tray's upward and downward movements with sheet discharge, adjusting positions based on curl type to prevent interference and ensure proper alignment of sheets.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the discharge tray angle is changed to conform to different sheet discharge openings, then the apparatus can handle both post-processed and non-post-processed sheets, but the sheet discharge is still adversely affected when sheets are curled upward or downward

Engineering Contradiction:

Improveadaptability to different sheet discharge conditionsVSAvoidreliability of sheet discharge

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The discharge tray is made movable in the sheet discharge direction rather than having a fixed angle. The tray position is dynamically adjusted based on sheet curl detection, allowing the system to adapt to different sheet conditions while maintaining reliable discharge by positioning the tray appropriately for each sheet type

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

A curl sensor detects the curl state of discharged sheets and provides feedback to the control unit. Based on this feedback, the control unit automatically adjusts the discharge tray position to compensate for sheet curl, ensuring reliable discharge regardless of whether sheets are curled upward or downward

Inventive Principle:

Principle #23Feedback

2Ease of operation

If the discharge tray is moved upward or downward after detecting abnormal discharge, then already occurred abnormalities can be addressed, but the sheet discharge abnormality cannot be prevented

Engineering Contradiction:

Improveability to correct discharge abnormalitiesVSAvoidprevention of sheet discharge abnormality

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The curl sensor detects sheet curl immediately upon discharge, and the control unit proactively adjusts the discharge tray position before abnormal discharge can occur. This preliminary adjustment prevents curl-induced discharge problems rather than correcting them after they happen

Inventive Principle:

Principle #10Preliminary action

3Extent of automation

If a curl sensor is used to detect sheet curl, then sheet discharge issues can be addressed, but slight curls cannot be detected leading to erroneous detection

Engineering Contradiction:

Improveautomation of curl detectionVSAvoidprecision of curl detection

Core Design Contradiction:

Extent of automationVSMeasurement precision

Solution Approach 1:

The system adjusts the discharge tray position based on the detected curl state, effectively changing the positional parameter to compensate for sheet curl. This parameter adjustment allows the system to handle both slightly curled and heavily curled sheets accurately

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS7549621B2Sheet post-processing apparatus

Publication Date: 2009.06.23 KYOCERA DOCUMENT SOLUTIONS INC

AI summary

A sheet post-processing apparatus is constructed to apply post-processing to sheets successively supplied from an image forming apparatus and received into an apparatus main body, and includes a main discharge tray onto which the sheets that have passed through the apparatus main body are discharged. The sheet post-processing apparatus further has an elevating mechanism for moving the main discharge tray up and down and a control unit for controlling an elevation control of the elevating mechanism. The control unit controls the elevating mechanism to move the main discharge tray up and down in synchronism with the discharge of the sheet onto the main discharge tray. The control unit carries out the elevation control of the main discharge tray so as not to adversely affect the discharge of a succeeding sheet even if the sheet discharged from the apparatus main body is curled up or down.