Charging Roller Support Segmentation for Followability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electrophotographic image forming apparatuses, the reduced core metal shaft diameter of charging rollers leads to slip between the photosensitive drum and the charging roller, causing charge potential differences and stripe non-uniformity in images, while attempts to enhance followability by lowering sliding torque result in reduced flexural rigidity and uneven contact.
Innovation Solution
A cartridge design with a core metal shaft and a coating layer, featuring cylindrical holes at the ends of the core metal shaft for improved support, and a regulating mechanism to enhance the roller's position alignment, ensuring better rotational and translational followability to the photosensitive drum while maintaining flexural rigidity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the core metal shaft diameter is reduced to lower sliding torque and enhance followability, then rotational followability improves, but flexural rigidity decreases causing uneven contact
Solution Approach 1:
The support structure is segmented into multiple bearing members distributed along the length of the core metal shaft. This segmentation allows each bearing member to provide localized support, maintaining rigidity where needed while permitting controlled rotation where required. The shaft is divided into multiple supported sections rather than being supported as a single unit.
Solution Approach 2:
Different sections of the core metal shaft have different support characteristics. The bearing members are positioned at specific locations to provide rotational support at endpoints while maintaining flexural rigidity in intermediate sections. This creates local variations in mechanical properties along the shaft length, optimizing both followability and structural integrity.
2Ease of operation
If the core metal shaft diameter is reduced to improve followability, then sliding torque decreases, but contact uniformity deteriorates
Solution Approach 1:
Multiple bearing members are distributed along the shaft to segment the support function. This ensures uniform contact pressure is maintained across different sections of the charging roller, preventing deformation that would cause non-uniform contact with the photosensitive drum.
Solution Approach 2:
The bearing members act as intermediary elements between the core metal shaft and the external environment. They mediate the mechanical stresses, providing rotational freedom while maintaining structural integrity and uniform contact characteristics through their bearing capability.
3Speed
If the core metal shaft diameter is reduced to enhance followability, then rotational responsiveness improves, but structural stability deteriorates
Solution Approach 1:
The support system is segmented into multiple discrete bearing members rather than a continuous support structure. This segmentation allows the shaft to rotate freely at each bearing point while the overall structure remains stable due to the distributed nature of the support points along the shaft length.
Solution Approach 2:
The bearing members serve multiple functions simultaneously: they support the shaft structurally, enable rotational motion, maintain positional stability, and preserve structural integrity. This multi-functionality resolves the contradiction between responsiveness and stability.
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 improves both rotational and translational followability of the charging roller, reducing sliding speed and maintaining uniform contact, thereby stabilizing high-quality electrophotographic image production and minimizing charging non-uniformity.
Implementation Method 1
a sliding torque between the supporting member and the core metal shaft is lowered by reducing a diameter of the core metal shaft of the charging roller
Implementation Method 2
the supporting members are supported movably in a radial direction of the photosensitive drum by a frame of the process cartridge, and are urged toward the photosensitive drum by compression coil springs with a predetermined urging force (pressure)
Implementation Method 3
a voltage is applied to the charging roller, so that a surface of the photosensitive drum is electrically charged
Data Source
AI summary
A cartridge includes a photosensitive member, a roller including a core metal shaft and a coating layer, roller supporting portions, and a regulating portion for regulating a position of the roller with respect to a longitudinal direction of the roller. The roller supporting portions are provided so as to support one end portion and an other end potion of the core metal shaft, respectively, with respect to a direction of a rotational axis of the roller. The roller is further provided with cylindrical holes disposed at respective ends of the core metal shaft with respect to the direction of the rotational axis and extending in the direction of the rotational axis with the rotational axis as a center. The roller is supported by the roller supporting portions at inner peripheral surfaces of the holes.