Cylindrical Shaft Separation Region for Image Forming Roller
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In image forming apparatuses, cylindrical metal shafts with hollow structures face issues with gaps or stepped portions at the ends, which affect sliding properties and require additional components to mitigate these issues, increasing complexity and cost.
Innovation Solution
A cylindrical shaft with a separation region on its circumference, where end portions oppose each other axially, is used in conjunction with a rotatable cylindrical member that is press-contacted to the shaft's outer surface, excluding the separation region, and an urging member to prevent rotation and enhance sliding properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If a cylindrical shaft is molded by bending a metal plate, then weight and material cost are reduced, but gaps or stepped portions are formed at end portions which adversely affect sliding property
Solution Approach 1:
The cylindrical shaft is segmented into a pressing portion and a non-pressing portion along its circumference. The pressing portion maintains continuous contact with the rotatable cylindrical member for reliable sliding, while the non-pressing portion contains the gap without affecting sliding performance. This segmentation allows the hollow structured shaft to maintain both weight reduction and sliding reliability.
2Ease of manufacture
If a cylindrical shaft is molded by bending a metal plate, then manufacturing cost is reduced, but additional components are required to cover gaps which increases device complexity
Solution Approach 1:
The rotatable cylindrical member serves multiple functions: it provides the sliding surface for the cylindrical shaft and simultaneously covers the gap at the end portions. By making the rotatable cylindrical member extend axially beyond the shaft ends, it universally performs both rotational guidance and gap coverage functions, eliminating the need for separate protective components.
3Adaptability or versatility
If end portions of metal plate abut against each other to form cylindrical shaft, then hollow structure is achieved, but gap or stepped portion is formed along axial direction
Solution Approach 1:
Different regions of the cylindrical shaft are assigned different functional qualities. The pressing portion along the circumference provides continuous sliding contact with high precision, while the non-pressing portion accommodates the inherent gap from plate bending. This local differentiation allows the shaft to achieve hollow structure while maintaining manufacturing precision where it matters for sliding contact.
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 simplifies the structure, improves sliding properties, and reduces manufacturing costs by eliminating the need for additional components to cover gaps, while ensuring effective rotation prevention and durability through continuous lubricant supply.
Implementation Method 1
a constitution in which the cylindrical shaft is pressed against the rotatable cylindrical member by an urging member
Data Source
AI summary
A roller is provided includes a cylindrical shaft supported by a main assembly of an image forming apparatus or a detachable cartridge. The cylindrical shaft includes a separation region on a circumference of the cylindrical shaft, where a pair of end portions of the cylindrical shaft oppose each other or are in contact with each other with respect to a circumferential direction relative to the circumference of the cylindrical shaft, and wherein the separation region extends in an axial direction of the cylindrical shaft. In addition, a rotatable cylindrical member is mounted around an outer circumference of the cylindrical shaft and is rotatable about the cylindrical shaft while an inner peripheral surface of the rotatable cylindrical member is in contact with an outer peripheral surface of the cylindrical shaft in a region of the cylindrical shaft other than the separation region with respect to the circumferential direction.