Corona Charger Shutter Cleaning Interval Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing charging devices with corona chargers face issues of upsizing due to the need for a gap between the cleaning member and the shutter, which can lead to deposition of foreign matter on the shutter during movement, causing image defects in high-humidity environments.
Innovation Solution
A charging device design that includes a mechanism to form an interval between the shutter and the cleaning member, allowing the cleaning member to move ahead of the shutter by a predetermined distance, with a stopper to prevent foreign matter deposition, and a driving mechanism that permits idling when the shutter closes, ensuring effective shielding without increasing the device size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a gap is provided between the cleaning member and the shutter leading end to suppress foreign matter deposition, then the shutter can move freely without contamination, but the corona charger must be upsized to maintain full shielding coverage
Solution Approach 1:
The cleaning member performs cleaning action before the shutter reaches its closing position. By advancing the cleaning member ahead of the shutter and cleaning the grid electrode in advance, foreign matter is removed before the shutter closes, preventing deposition on the shutter while maintaining compact dimensions
Solution Approach 2:
The movement control is segmented into distinct phases: the cleaning member moves independently ahead of the shutter to perform cleaning, then the shutter closes separately. This temporal and spatial segmentation allows the cleaning function to be completed before shutter closure without requiring additional space for simultaneous operation
2Manufacturing precision
If the cleaning member moves ahead of the shutter to clean the grid electrode, then foreign matter is removed effectively, but there is a risk that cleaned foreign matter may deposit on the shutter during movement
Solution Approach 1:
The cleaning member advances and completes the cleaning action before the shutter closes. By performing the cleaning operation in advance and maintaining the cleaning member ahead of the shutter during the cleaning phase, foreign matter is removed and deposited on the grid electrode surface rather than on the shutter
Solution Approach 2:
The grid electrode surface acts as an intermediary between the cleaning member and the shutter. Foreign matter removed by the cleaning member is deposited on the grid electrode surface, which serves as a temporary holding surface, preventing direct deposition on the shutter while maintaining cleaning effectiveness
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 design effectively suppresses the deposition of foreign matter on the shutter, preventing image defects while maintaining the compact size of the charging device, thus addressing the challenge of upsizing and image flow issues.
Implementation Method 1
An image forming apparatus of an electrophotographic type in which a photosensitive member is electrically charged by a corona charger
Implementation Method 2
a cleaning member for cleaning the grid electrode
Data Source
AI summary
A charging device includes: a casing provided with an opening opposing a member-to-be-charged; a discharging wire provided in the casing; a grid electrode provided in the opening; a shutter for opening and closing the opening; a cleaning member for cleaning the grid electrode; and a moving mechanism for reciprocating the shutter and the cleaning member along a longitudinal direction of the opening. The moving mechanism includes a driving member for being rotationally driven, a first moving member, held by the driving member, for moving the shutter with rotational drive of the driving member, and a second moving member, held by the driving member, for moving the cleaning member with the rotational drive of the driving member. The charging device further includes: a mechanism for forming an interval between the shutter and the cleaning member so that the cleaning member moves in advance of the shutter by a predetermined distance when the shutter moves in a closing direction; and a stopper for stopping movement of the cleaning member, and the second moving member includes a holding portion for permitting idling when the shutter moves in the closing direction toward the cleaning member, stopped by the stopper, with rotation of the driving member.