Regulation Member with Varying Diameters for Uniform Image Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electrophotographic image forming apparatuses, non-uniform regulating gaps between the developing roller and the regulation member lead to uneven image density due to the varying amounts of developing agent adhered to the roller's surface, causing contamination and image quality issues.
Innovation Solution
A rod-shaped regulation member with varying diameters at the central and end portions is used, where the sealing member applies a pressing force to compensate for the non-uniformity of the regulating gap, ensuring uniformity along the longitudinal direction by adjusting the gap size through deformation, thereby maintaining consistent developing agent thickness and preventing leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a regulation member with uniform diameter is used, then the structure is simple and easy to manufacture, but the regulating gap becomes non-uniform along the longitudinal direction due to pressing force, causing uneven image density
Solution Approach 1:
The regulation member is designed with non-uniform diameter along its longitudinal direction, where the diameter varies at different positions (central portion vs. end portions). This local variation in geometry allows different regions of the regulation member to compensate for non-uniform pressing forces, thereby achieving uniform regulating gap and uniform image density across the developing roller surface.
2Manufacturing precision
If the regulating gap is made uniform, then image density uniformity is improved, but the device complexity increases due to the need for precise diameter variation in the regulation member
Solution Approach 1:
The invention changes the geometric parameter (diameter) of the regulation member along its longitudinal direction. By designing the regulation member with varying diameter parameters at different positions, the system achieves uniform regulating gap without requiring complex control mechanisms or additional components, thus improving image density uniformity while keeping the overall device structure relatively simple.
3Manufacturing precision
If the regulation member deforms under pressing force, then the regulating gap uniformity is improved, but the stability of the regulation member shape deteriorates
Solution Approach 1:
The regulation member is pre-designed with a non-uniform diameter profile that anticipates and compensates for the deformation that will occur under pressing force. This preliminary geometric configuration ensures that when the pressing force is applied during operation, the resulting deformation leads to a uniform regulating gap, while the member maintains sufficient shape stability for reliable operation.
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 achieves uniform image density across the longitudinal direction of the developing roller, reducing contamination and enhancing the image forming process by ensuring a consistent thickness of the developing agent layer, which is essential for high-quality printing.
Implementation Method 1
the sealing member applies a pressing force to compensate for the non-uniformity of the regulating gap, ensuring uniformity along the longitudinal direction by adjusting the gap size through deformation
Implementation Method 2
The developing agent accommodated in the developing device is adhered to the outer periphery of a developing sleeve by a magnetic force
Data Source
AI summary
A developing device may include a housing to accommodate a developing agent, a developing roller to convey the developing agent adhered to an outer periphery of the developing roller to an outside of the housing, a regulation member positioned apart from the developing roller and having a circular cross-sectional shape to regulate a thickness of the developing agent adhered to the developing roller, and a sealing member between the regulation member and the housing to prevent leakage of the developing agent. A diameter of a central portion of the regulation member may be different from diameters of both end portions of the regulation member.