Process Cartridge Roller Velocity Ratio Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The extension of electrophotographic apparatus service life leads to unstable abutment states between the toner-supplying roller, developing roller, and photosensitive member, causing streak-like unevenness in images due to increased dynamic friction coefficients, which existing configurations fail to adequately address.
Innovation Solution
A process cartridge configuration where the developing roller and toner-supplying roller have opposite surface movement directions at their contact point, with a peripheral velocity ratio between 1.2 and 1.5, and the toner-supplying roller includes a shaft body and resin layer, while the photosensitive member features a polyarylate resin surface layer with specific structural units to stabilize toner supply and reduce friction fluctuations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the counter configuration is adopted to stabilize toner supply from the toner-supplying roller to the developing roller, then the toner supply amount is stabilized, but the dynamic friction coefficient in the abutment portion between the developing roller and the photosensitive member increases, causing banding images
Solution Approach 1:
The patent changes the peripheral velocity ratio parameter between the toner-supplying roller and developing roller to a specific range (1.05 ≤ R < 1.20) to optimize the counter configuration. This parameter adjustment stabilizes toner supply while controlling the dynamic friction coefficient to prevent banding images, resolving the contradiction between toner supply stability and image quality.
2Duration of action of stationary object
If the electrophotographic apparatus service life is extended, then the apparatus can be used longer, but the surface states of the toner-supplying roller, developing roller, and photosensitive member change, causing unstable abutment state and banding images
Solution Approach 1:
The patent introduces dynamic control of the peripheral velocity ratio between rollers, adjusting it within a specific range (1.05 ≤ R < 1.20) during operation. This dynamic adjustment compensates for surface state changes that occur during extended use, maintaining stable abutment conditions and preventing banding images even as the apparatus service life extends.
3Quantity of substance
If the abutment pressure between the developing roller and toner-supplying roller is increased to improve toner supply, then the toner supply amount increases, but the developing roller becomes harder to deform, causing banding images
Solution Approach 1:
The patent optimizes the peripheral velocity ratio parameter (1.05 ≤ R < 1.20) to achieve effective toner supply without requiring excessive abutment pressure. This parameter change allows sufficient toner transfer while maintaining roller deformability, preventing banding images that would otherwise occur with high pressure.
Data Source
AI summary
Provided is a process cartridge being detachably attachable onto a main body of an electrophotographic apparatus. The process cartridge includes an electrophotographic photosensitive member, a developing roller, and a toner-supplying roller. The developing roller and the toner-supplying roller are rotated so as to satisfy a particular velocity ratio so that the surface of the developing roller and the surface of the toner-supplying roller are opposite to each other at a contact position therebetween. The surface of the developing roller is a surface of an elastic layer, and the toner-supplying roller includes a shaft body and a resin layer formed on an outer peripheral surface of the shaft body. The electrophotographic photosensitive member includes a surface layer containing a polyarylate resin including a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2).