Adjustable Gate Member for Sheet Skew Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sheet conveying devices struggle to perform accurate skew correction across varying paper thicknesses, leading to instability and inaccuracies in image positioning, especially with thin and thick papers.
Innovation Solution
A sheet conveying device with a gate member and a roller pair, where the gate member's contact surface is adjustable based on paper thickness, allowing precise skew correction by abutting the leading end of the sheet and utilizing the sheet's stiffness for alignment, ensuring accurate conveyance to the nip position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the gate member is positioned close to the nip, then thin paper is conveyed smoothly, but thick paper cannot be properly skew corrected
Solution Approach 1:
The gate member is made movable along the sheet conveying direction, allowing its position to be dynamically adjusted. This enables the system to adapt to different paper thicknesses by positioning the gate member at optimal locations - closer to the nip for thin paper and farther away for thick paper - thereby resolving the contradiction between skew correction accuracy and thick paper compatibility
2Adaptability or versatility
If the gate member is positioned far from the nip, then thick paper can be skew corrected, but thin paper conveyance becomes unstable
Solution Approach 1:
The movable gate member allows dynamic repositioning to maintain optimal distance from the nip based on paper thickness. For thick paper, the gate member is positioned farther away to allow proper skew correction, while for thin paper it is positioned closer to ensure stable conveyance, thus resolving the contradiction
3Device complexity
If a fixed gate member position is used, then the structure is simple, but skew correction accuracy varies with paper thickness
Solution Approach 1:
The gate member is configured to be movable along the sheet conveying direction while maintaining rotational synchronization with the registration roller pair. This dynamic positioning capability allows the system to optimize skew correction accuracy for different paper thicknesses without significantly increasing structural complexity, as the movement mechanism integrates with the existing roller pair rotation
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
A sheet conveying device (26), which is incorporated in an image forming apparatus, includes a sheet holding and conveying roller pair (48) to convey a sheet (20) while holding the sheet (20) at a nip (N), and a gate member (64) disposed movable with rotation of the sheet holding and conveying roller pair (48) to correct skew of the sheet (20) in a sheet conveying direction while a leading end of the sheet (20) in the sheet conveying direction abuts against the gate member (64). The gate member (64) has a contact surface (64a) against which the sheet (20) abuts. The contact surface (64a) is disposed upstream from the nip (N) of the sheet holding and conveying roller pair (48) in the sheet conveying direction. A setting position of the contact surface (64a) is adjusted according to thickness of the sheet (20).