Ejection Tray Stopper Member for Sheet Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In image forming apparatuses, the reduction in size of the ejection tray can lead to nonstandard size sheets falling due to curling issues caused by sheet type and environment, resulting in stock failures and sheet ejection problems.
Innovation Solution
An ejection tray with a stopper member that can be turned from a storage posture to a restriction posture using a deep second recess and guide projections, allowing for easy and stable engagement and support to prevent sheet falling, facilitated by a latch mechanism for automatic transition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the ejection tray size is reduced to minimum to promote reduction in size of the image forming apparatus, then the device size is reduced, but nonstandard size sheets may fall from the ejection tray causing stock failure
Solution Approach 1:
The stopper member is designed to be movable between a first position (preventing sheets from falling off) and a second position (clearing the ejection path). This dynamic adjustment allows the minimal-sized ejection tray to reliably handle both standard and nonstandard sheets while maintaining compact dimensions.
Solution Approach 2:
The stopper member is configured to be automatically pushed by the sheet itself during ejection. When a sheet is ejected, it naturally pushes the stopper member to the second position, eliminating the need for additional actuators or complex control mechanisms while ensuring reliable sheet guidance.
2Reliability
If a stopper member is added to prevent sheets from falling, then sheet ejection reliability is improved, but the device complexity increases
Solution Approach 1:
The stopper member utilizes the kinetic energy of the ejected sheet itself to transition from the first position to the second position. This self-actuating mechanism eliminates the need for motors, solenoids, or complex control systems, thereby improving reliability while minimizing structural complexity.
Solution Approach 2:
The stopper member is designed as a separate, independent component that can be easily integrated into the ejection tray structure. This modular approach allows the reliability function to be added without fundamentally redesigning the entire ejection system, thus limiting the increase in device complexity.
3Ease of operation
If the stopper member is designed to be turned manually, then ease of operation is improved, but the turning action may be difficult when the pressed part is small
Solution Approach 1:
The storage part is designed with a stepped structure having different depth levels. The pressed part is positioned in a deeper region that provides greater vertical clearance, allowing users to easily press and turn the stopper member without interference from the ejection tray surface, thereby improving operability without adding mechanical complexity.
Solution Approach 2:
The storage part is segmented into multiple recesses at different depths. This segmentation creates dedicated spaces for different components: the deeper recess accommodates the pressed part with sufficient clearance for manual operation, while shallower recesses store other components. This spatial organization improves ease of operation without increasing overall device complexity.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An image forming apparatus (1) includes a stopper member (32) supported either in a storage posture stored in a storage part (35) by turning in an upstream side or a restriction posture to prevent falling down of a sheet from a sheet stacking face (30) by turning in a downstream side. The storage part (35) has a first recess (36) and a second recess (37) deeper than the first recess (36). The stopper member (32) has a base end part (52) supported in the second recess (37) movably upward and downward and a main part (51) supported in the first recess (36) in the storage posture. When the base end part (52) is pressed downward in the storage posture, the base end part (52) is moved downward and the main part (51) comes into contact with a downstream side edge of the first recess (36), the stopper member (32) is turned around the downstream side edge into the restriction posture through a protrusion posture protruding above the sheet stacking face (30).