Foamed Roller Protective Agent Supply for Image Bearing Member
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrophotographic image forming apparatuses face issues with abrasion and contamination due to the deterioration of lubricative films on image bearing members under physical and electrical stresses, leading to defective images and contamination of charging members.
Innovation Solution
A protective agent supply device using a foamed roller with open cells and a pressing unit to constantly supply a metal salt of a fatty acid-based protective agent, preventing abrasion and contamination by forming a uniform protective layer on the image bearing member.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a solid lubricant is pressed against the brush roller with a spring to form a lubricative film, then the image bearing member is protected from abrasion, but the pressing force of the spring gradually weakens and the amount of protective agent supplied gradually reduces
Solution Approach 1:
The patent replaces the static spring pressing mechanism with a dynamic roller pressing mechanism that maintains constant pressing force through rotational motion and elastic deformation of the roller, ensuring consistent protective agent supply over extended periods without force degradation
Solution Approach 2:
The roller mechanism automatically compensates for protective agent consumption through continuous rotation and pressing, maintaining constant supply pressure without requiring external adjustment or replacement, enabling long-term autonomous operation
2Reliability
If zinc stearate is used as a lubricant to protect the image bearing member from electrical stress, then electrical protection is improved, but toner particles slip through the cleaning blade due to lubricity, causing contamination
Solution Approach 1:
The patent modifies the chemical composition parameters of the protective agent by replacing zinc stearate with metal soaps of higher molecular weight fatty acids (arachidic, behenic, lignoceric acids), which provide electrical stress protection while having sufficient molecular structure complexity to prevent toner particle slippage
Solution Approach 2:
The patent creates a composite protective agent system combining metal soaps with specific molecular weight ranges and controlled purity levels, achieving a balance between electrical protection properties and toner adhesion characteristics that prevents contamination
3Reliability
If the solid lubricant is consumed, then the protective function is maintained initially, but the pressing force weakens and supply amount reduces over time
Solution Approach 1:
The patent implements a dynamic pressing system where the roller's rotational motion and elastic properties maintain constant contact pressure with the protective agent reservoir, ensuring that the supply amount remains consistent even as the reservoir is consumed, unlike static spring mechanisms that lose force
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
The solution ensures a constant and reliable protection of the image bearing member from abrasion and contamination, maintaining image quality and extending the lifespan of the charging member by preventing toner slipping and distortion.
Implementation Method 1
a rotatable foamed roller... that scrapes the protective agent block and supplies the scraped protective agent to the outer peripheral surface of an image bearing member
Implementation Method 2
a pressing unit that presses the protective agent block against the foamed roller
Data Source
AI summary
A novel protective agent supply device is provided including a protective agent block including a metal salt of a fatty acid; a rotatable foamed roller having a foamed layer having open cells, that is in continuous contact with both the protective agent block and an outer peripheral surface of an image bearing member that bears a toner image, and that scrapes the protective agent block and supplies the scraped protective agent to the outer peripheral surface of the image bearing member during rotation of the foamed roller; and a pressing unit that presses the protective agent block against the foamed roller.