Drum Unit Shutter Mechanism for Toner Leak Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrophotographic image forming apparatuses face challenges with the size of the image forming unit due to the inclusion of a waste toner container and issues with precise positioning of process cartridges caused by unintentional shutter opening during attachment or detachment, leading to potential toner leaks.
Innovation Solution
The design includes a drum unit with a movable waste toner container and a shutter system where the shutter is positioned upstream of the photoconductive drum, allowing controlled opening and closing to prevent toner leaks and facilitate precise positioning by using a protruding section that interacts with the main body casing's contact section to rotate the shutter from a closed to an open position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the waste toner container is disposed inside the image forming apparatus, then the image forming unit can be made more compact, but the shutter may unintentionally open when the image forming unit is attached or detached, causing toner to leak from the transportation tube
Solution Approach 1:
The protruding section is positioned upstream of the photoconductive drum in the moving direction, so that when the image forming unit is inserted, the protruding section contacts the contact section first and preliminarily opens the shutter before the drum reaches the cleaning position. This ensures the shutter is opened in advance to prevent toner leakage during attachment, while maintaining compact design by keeping the waste toner container inside the apparatus.
2Ease of operation
If the shutter is opened by a motor after process cartridges are positioned, then the opening can be controlled, but the force applied to open the shutter causes the process cartridges to be urged in the detachment direction, making precise positioning difficult
Solution Approach 1:
The shutter opening mechanism utilizes the insertion force of the image forming unit itself. As the image forming unit is inserted into the apparatus, the protruding section automatically contacts the contact section and opens the shutter through the mechanical interaction between these components. This self-opening mechanism eliminates the need for separate motor-driven opening that would apply unwanted forces to the process cartridges, thereby maintaining precise positioning while ensuring reliable shutter opening at the appropriate timing.
Data Source
AI summary
An image forming apparatus includes a drum unit movable between an inside position inside a main body casing and an outside position outside the main body casing. The drum unit includes a photoconductive drum extending in an axial direction intersecting a moving direction of the drum unit from the outside position toward the inside position, and a transporter transporting toner removed by a cleaner toward a waste toner container. The transporter includes a transportation member transporting the toner along the moving direction, a transportation tube accommodating the transportation member and having an outlet, and a shutter movable between a closed position to close the outlet and an open position to open the outlet. The shutter includes a protruding section protruding along the axial direction from a shutter main body when the shutter is in the closed position, the protruding section being upstream of the photoconductive drum in the moving direction.