Releasable Drum Unit Alignment Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In image forming apparatuses, removably installable units such as development and drum units can fail to be completely installed, leading to improper alignment and potential damage of bearings, resulting in image defects due to forced contact and friction during the installation process.
Innovation Solution
An image forming apparatus with a rotatable openable member and a pressing mechanism that ensures the units are properly aligned and separated during installation, using a contact surface with a specific angle to prevent the door from completely closing if the units are not fully installed, thereby avoiding bearing contact and potential damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the door is closed to push the unit into the main assembly, then the unit installation is completed, but the bearings are forced to rub against each other causing damage
Solution Approach 1:
The pressing mechanism is activated before the door closing operation to pre-align the units and separate the bearings. This preliminary action ensures that when the door subsequently closes to push the unit into the main assembly, the bearings are already in correct positions and will not be forced to rub against each other, thus completing the installation without damaging the bearings
Solution Approach 2:
The pressing mechanism acts as an intermediary device between the door closing operation and the unit installation. It mediates the force application by first pressing the image bearing member unit and developer carrying member together to align them, then releasing to allow bearing separation, so that the door can close without directly causing bearing contact and damage
2Manufacturing precision
If the units are pressed together to ensure bearing contact, then the SD gap is maintained, but the bearings may be damaged during installation
Solution Approach 1:
The pressing mechanism provides dynamic control over the pressing force and timing. It presses the units together only when needed to establish correct alignment and SD gap, then releases the pressure to allow bearing separation during door closing. This dynamic approach maintains manufacturing precision for the SD gap while avoiding the harmful static pressure that would damage bearings during installation
Solution Approach 2:
The pressing mechanism operates in periodic cycles: press to align units and establish SD gap, then release to allow bearing separation. This periodic action repeats during the installation process, ensuring that the SD gap precision is maintained through intermittent pressing while the release phases prevent continuous bearing contact and potential damage
3Device complexity
If the door is designed to push units into the main assembly, then installation is simplified, but improper alignment and bearing damage occur
Solution Approach 1:
The pressing mechanism performs preliminary alignment of the image bearing member unit and developer carrying member before the door pushing operation. By pre-establishing the correct relative positions and SD gap through controlled pressing, the subsequent door closing action simply completes the installation without causing misalignment or bearing damage, thus maintaining simplicity while improving reliability
Data Source
AI summary
An image forming apparatus includes an image bearing member unit; a developing unit; an accommodating portion configured to accommodate the image bearing member unit and the developing unit and provided with an inserting opening; a door for the opening; a pressing mechanism for pressing and releasing the image bearing member unit and the developing unit relative to each other in interrelation with the openable member; and a contact surface provided on the openable member, the contact surface is contactable with an upstream end portion of one of the units, when the openable member is closed in a state that the upstream end portion is projected out of the opening, wherein an angle formed between a normal line of the contact surface and the inserting direction in a downstream side is not less than 90 degrees.