Paper Feed Tray Height Retry Control for Guide-Member Misfeeds
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing paper feeding apparatuses are prone to misfeeds due to the leading edge of the sheet of paper biting into the guide member, which is formed of a rubber material with a high friction coefficient, causing resistance and leading to picking errors.
Innovation Solution
A paper feeding apparatus with a tray, delivery roller, paper feeding roller, and guide member that is inclined upward, combined with a lifting/lowering mechanism and controller to adjust the tray height, allowing retry processing and tray lifting/lowering to prevent sheet biting into the guide member.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the guide member is formed of a rubber material with a high friction coefficient to suppress sheet separation error, then sheet separation error is reduced, but the leading edge of the sheet is likely to bite into the guide member causing picking error
Solution Approach 1:
The tray is made movable in the sheet thickness direction through a lifting/lowering mechanism. During retry processing, the tray height is dynamically adjusted by lifting and lowering it within a predetermined range, which changes the engagement position between the sheet leading edge and the guide member, thereby eliminating the biting phenomenon while preserving the high-friction surface's sheet separation suppression capability
Solution Approach 2:
The height parameter of the tray is changed during retry processing by lifting and lowering it within a predetermined range. This parameter change adjusts the relative position between the sheet and guide member, allowing the sheet leading edge to properly engage with the paper feeding roller instead of biting into the guide member, while maintaining the guide member's high friction coefficient for preventing sheet separation
2Reliability
If retry control is performed by stopping and restarting the paper feeding roller when misfeed occurs, then misfeed detection is possible, but the flapper must move up and down to prevent slipping which adds complexity
Solution Approach 1:
The invention extracts and removes the flapper component from the retry processing mechanism. Instead of using flapper movement to prevent sheet slipping during retry, the solution uses tray height adjustment, thereby simplifying the device structure by eliminating the need for flapper actuation during error recovery
Solution Approach 2:
The tray is given multiple functions: it serves as both the sheet support structure and the active element for preventing sheet slipping during retry processing. By lifting and lowering the tray, the same structure that holds the sheets also performs the corrective action, eliminating the need for a separate flapper mechanism
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces misfeeds by ensuring the sheet leading edge properly engages with the paper feeding roller, enhancing feeding reliability and reducing double feeds.
Implementation Method 1
the guide member is formed of a rubber material having a high friction coefficient, and therefore the guide member serves as a resistance against the sheet of paper to be fed
Data Source
AI summary
An image forming apparatus includes: a tray; a delivery roller; a paper feeding roller; a guide member; a lifting/lowering mechanism; a first detector; and a controller. The controller executes paper feeding processing of feeding a sheet of paper delivered from the tray by rotating the paper feeding roller, executes, during the paper feeding processing, retry processing of resuming the paper feeding processing after stopping the paper feeding processing when the fed sheet of paper is not detected by the first detector, and executes, during the retry processing, lifting and lowering processing of lifting and lowering the tray within a predetermined range after stopping the paper feeding processing and before resuming the paper feeding processing. The predetermined range is a range in which an uppermost sheet of paper placed on the tray can abut on the guide member when the uppermost sheet of paper is delivered by the delivery roller.