Transfer Sheet Guide Angle and Gap for Image Quality
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image forming apparatuses using the intermediate transfer method face issues with toner spattering and pinholes due to gaps between the transfer sheet and intermediate transfer belt, leading to poor image quality, despite existing solutions like adjusting the angle between the guide surface and the intermediate transfer belt.
Innovation Solution
An image forming apparatus with a specific configuration including a guide member that guides the transfer sheet at an angle of 13° to 17° and a distance of 1.0 mm to 3.0 mm from the image holding belt, ensuring stable contact and preventing toner spattering and pinholes, along with mechanisms to maintain positional accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the angle between the guide surface and the intermediate transfer belt is adjusted to 0° to 40°, then the transfer sheet is more likely to contact the intermediate transfer belt, but stable contact and prevention of toner spattering are not achieved
Solution Approach 1:
The patent applies parameter changes by precisely defining the guide surface angle within 0° to 10° and the distance between 1mm to 5mm from the intermediate transfer belt. This narrow parameter range resolves the contradiction by transforming the vague 0°-40° range into specific, optimized values that ensure stable contact while preventing toner spattering and pinholes.
2Productivity
If a small gap exists between the transfer sheet and the intermediate transfer belt before the transfer nip, then the transfer sheet can enter the nip, but toner spattering and pinholes occur due to electric field discharge
Solution Approach 1:
The patent introduces a guide surface as an intermediary element that mediates between the transfer sheet and the intermediate transfer belt. The guide surface, positioned at a specific angle and distance, ensures the transfer sheet makes proper contact with the belt before entering the transfer nip, thereby preventing harmful electric field discharge while maintaining transfer productivity.
3Reliability
If the guide surface is positioned closer to the intermediate transfer belt, then contact is improved, but the transfer sheet may not pass through smoothly
Solution Approach 1:
The patent resolves this contradiction by optimizing the distance parameter between the guide surface and the intermediate transfer belt to be 1mm to 5mm. This specific parameter range ensures sufficient contact stability while maintaining smooth transfer sheet passage, avoiding the need for excessively precise positioning that would increase device complexity.
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
This configuration stabilizes contact between the transfer sheet and the image holding belt, resulting in a favorable transfer image without toner spattering and pinholes, even at varying processing speeds and transfer sheet thicknesses.
Implementation Method 1
a transfer electric field being generated between the transfer roller and the first roller, and the toner image being transferred from the surface of the image holding belt to a transfer sheet that passes through the transfer nip
Data Source
AI summary
In an image forming apparatus, a toner image formed on an intermediate transfer belt is transferred to a transfer sheet by a transfer electric field generated between a secondary transfer roller and a driving roller. A guide surface of a pre-transfer guide and a flat portion of the intermediate transfer belt form an angle of no less than 13° and no greater than 17°, and a distance from a tip of the guide surface and the flat portion is no less than 1.0 mm and no greater than 3.0 mm.