Drive Transmission Rotating Body for Image Forming Apparatus
Solution Overview
Problem
Image forming apparatuses face issues with rotational non-uniformities in rotating bodies like the photosensitive drum and developing roller, leading to density non-uniformities in the images formed, due to eccentricities and inaccurate transmission of driving force, which conventional integrated frame and bearing solutions fail to adequately address.
Innovation Solution
An image forming apparatus with a frame that includes a positioning portion for the cartridge and a driving force transmission rotating body supported by a circumferential surface on the frame, allowing for accurate positioning and reduced rotational non-uniformities through the use of a separate drive transmission member and drive coupling member, which are designed to engage and transmit force effectively without inclination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If bearings and frame are formed integrally to improve rotational accuracy, then positioning precision of bearings is improved, but the structure becomes more complex and manufacturing difficulty increases
Solution Approach 1:
The patent merges the bearing support function directly into the frame structure by forming protrusions on the frame that directly support the rotating bodies. This integration eliminates separate bearing components and their positioning requirements, achieving high rotational accuracy while simplifying the overall structure compared to using separate precision bearings with complex mounting arrangements.
2Ease of operation
If frame and process cartridge are positioned separately and coupled by screws, then assembly flexibility is improved, but positioning errors occur between frames leading to reduced rotational accuracy
Solution Approach 1:
The patent segments the positioning function by providing dedicated positioning protrusions on the frame that directly engage with corresponding features on the process cartridge. This segmentation allows the cartridge to be easily installed and removed while ensuring precise positioning without relying on multiple coupled frames, thereby maintaining both assembly flexibility and rotational accuracy.
3Ease of manufacture
If drive transmission mechanism uses multiple separate components, then ease of manufacture is improved, but rotational non-uniformities increase due to positioning errors
Solution Approach 1:
The patent merges the drive transmission function into the frame structure itself by forming drive transmission rotating bodies that are directly supported by the frame's protrusions. This integration eliminates the need for multiple separate transmission components and their associated positioning errors, achieving reliable rotational uniformity while maintaining ease of manufacture through the simplified integrated structure.
Data Source
AI summary
Provided is a technique for suppressing the occurrence of density non-uniformities in an image formed on a sheet. An image forming apparatus, which forms an image on a recording material by transmitting driving force to a cartridge, includes: a frame having a positioning portion which positions the cartridge by contacting the attached cartridge; a driving force transmission rotating body which transmits driving force by engaging with a driving force receiving portion of the driven unit; and a circumferential surface which is provided in one portion of the frame and rotatably supports the driving force transmission rotating body.