Developing Cartridge Coupling for Uniform Roller Drive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electrophotographic image forming apparatuses face challenges in preventing rotation non-uniformity of the developing roller and require complex mechanisms for moving coupling members, which affects image formation speed and efficiency.
Innovation Solution
A developing apparatus with a coupling member that can engage with a driving shaft from a direction substantially perpendicular to the axial direction, allowing for smooth rotation of the developing roller without the need for solenoid-driven mechanisms, and featuring angular positions for efficient force transmission and disengagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a gear engagement mechanism is used to rotate the developing roller, then the developing roller can be rotated, but rotation non-uniformity occurs and is difficult to prevent
Solution Approach 1:
The patent replaces the gear engagement mechanism with a direct coupling mechanism. The coupling member engages with the driving shaft through a coupling hole and coupling protrusion, eliminating the intermediate gear transmission that caused rotation non-uniformity. This direct mechanical connection ensures more uniform rotation of the developing roller.
2Ease of operation
If a main assembly-side coupling is retracted and moved using a solenoid mechanism, then the coupling can connect to the developing device-side coupling, but the image formation time is increased and the mechanism becomes complex
Solution Approach 1:
The patent removes the solenoid-driven moving mechanism from the main assembly. Instead of retracting and moving a main assembly-side coupling, the invention uses a coupling member on the developing cartridge side that can be directly engaged with the driving shaft. This extraction of the complex moving mechanism eliminates the time delay and structural complexity.
Solution Approach 2:
The patent inverts the traditional coupling approach by placing the coupling member on the developing cartridge side rather than on the main assembly side. This allows the coupling to be directly engaged with the driving shaft without requiring the main assembly to provide a moving mechanism, thereby simplifying the overall structure and reducing image formation time.
3Ease of operation
If a complex mechanism with solenoid is provided in the main assembly to move the coupling, then the coupling connection can be achieved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent extracts the complex solenoid-driven moving mechanism from the main assembly entirely. The coupling connection is achieved through a simpler coupling member with a coupling hole and coupling protrusion that engages directly with the driving shaft, significantly reducing manufacturing complexity and cost.
Data Source
AI summary
An electrophotographic image forming apparatus comprises a main assembly that includes moving force applying portion, a main assembly engaging portion having a driving shaft and a rotational force applying portion provided on the driving shaft, and an electrophotographic photosensitive drum. A cartridge is dismountable from the main assembly without dismounting the electrophotographic photosensitive drum from the main assembly. The cartridge includes a developing roller for developing a latent image formed on the electrophotographic photosensitive drum, a rotatable member for transmitting a rotational force to the developing roller, and a coupling member including a rotational force receiving portion engageable with the rotational force applying portion to receive a rotational force from the main assembly engaging portion, and a rotational force transmitting portion for transmitting the rotational force to the rotatable member. The cartridge also includes a frame including a moving force receiving portion that receives a moving force from the moving force applying portion, the frame supporting the developing roller and the rotatable member.