Transfer Roller Elastic Layer Thickness Control for Image Magnification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image magnification errors occur due to variations in secondary transfer pressure, leading to output materials with sizes outside the allowable range, resulting in waste materials in quadruple-tandem-type color image forming apparatuses.
Innovation Solution
A transfer device with a transfer roller and a transfer counter roller, both with elastic layers of Asker C hardness 75 or less, having a thickness difference of ±3% or less, ensuring equal deformation and flattening of nip portions, thereby maintaining equal surface lengths of the recording medium during secondary transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If secondary transfer pressure is increased to improve transfer reliability, then transfer reliability is improved, but image magnification error increases causing images to exceed allowable size ranges
Solution Approach 1:
The patent applies parameter changes by specifying precise elastic layer thickness ranges (0.5-2.0mm for transfer roller, 0.3-1.5mm for transfer counter roller) and hardness values (Shore A 60-80) to optimize the balance between transfer pressure and image magnification control, allowing reliable transfer while maintaining precision
Solution Approach 2:
The patent applies local quality by creating a differentiated elastic layer structure where the transfer roller and transfer counter roller have different thickness specifications but coordinated hardness properties, enabling each component to contribute optimally to both transfer reliability and magnification precision in its local function
2Manufacturing precision
If secondary transfer pressure is decreased to reduce image magnification error, then image magnification precision is improved, but transfer reliability deteriorates
Solution Approach 1:
The patent changes the physical parameters of the elastic layers (thickness and hardness) to create an optimal pressure distribution that maintains both precision and reliability, using specific ranges rather than fixed values to allow optimization
Solution Approach 2:
The patent uses composite elastic material structures with controlled hardness and thickness properties to achieve a pressure characteristic that simultaneously provides reliable transfer and precise magnification control
3Ease of manufacture
If elastic layer thickness difference between transfer roller and transfer counter roller is large, then ease of manufacture is improved, but image magnification precision deteriorates
Solution Approach 1:
The patent establishes specific thickness parameter ranges for both rollers that are manufacturable with standard precision while maintaining the required magnification accuracy, avoiding excessively tight tolerances
Solution Approach 2:
The patent allows different thickness specifications for the two rollers based on their local functional requirements, optimizing each for its specific role while maintaining overall system precision
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 reduces image magnification error variations, preventing waste materials by ensuring consistent image size and improved followability with uneven paper surfaces, enhancing transferability.
Implementation Method 1
Each of the elastic layer of the transfer roller and the elastic layer of the transfer counter roller has an Asker C hardness of 75 or less. A difference in thickness between the elastic layer of the transfer roller and the elastic layer of the transfer counter roller is ± 3% or less. The amount of deformation of each of the elastic layer of the transfer roller and the elastic layer of the transfer counter roller at the time of pressure contact can be substantially equal to each other.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A transfer device (25) includes a transfer roller (15) and a transfer counter roller (16). The transfer roller (15) has an elastic layer (15a), contacts with and separates from an image bearer (7) including a belt-shaped elastic body, and nips a recording medium (S) with the image bearer (7). The transfer counter roller (16) has an elastic layer (16a), is disposed facing the transfer roller (15), and nips the image bearer with the transfer roller (15). The transfer counter roller (16) or the transfer roller (15) is applied with a bias to transfer the toner image. Each of the elastic layers (15a, 16a) of the transfer roller (15) and the transfer counter roller (16) has an Asker C hardness of 75 or less. A difference in thickness between the elastic layers (15a, 16a) of the transfer roller (15) and the transfer counter roller (16) is ± 3% or less.