Developing Device Discharge Screw for Carrier Performance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In image forming apparatuses using a two-component developing method, the carrier's charging performance deteriorates over time due to toner consumption and carrier circulation, leading to inefficient development processes.
Innovation Solution
A developing device with a unique configuration featuring a developing container, first and second stirring conveyance members, and a developer carrying member, which includes a discharge passage with a discharge screw and a discharge regulating member to manage surplus developer and maintain optimal toner distribution, preventing carrier deterioration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If the carrier circulates in the developing device without being consumed, then the developing process can continue, but the charging performance of the carrier deteriorates over time
Solution Approach 1:
The patent implements a discharge passage that discards surplus developer (including depleted carrier) from the developing container. This allows continuous operation by removing degraded carrier while recovering and replenishing fresh developer, thereby maintaining carrier charging performance over extended circulation periods
2Reliability
If surplus developer is discharged from the developing container, then carrier deterioration is prevented, but the device complexity increases due to additional discharge components
Solution Approach 1:
The discharge screw combines multiple functions: it conveys surplus developer through the discharge passage, regulates developer flow, and integrates with the existing developing container structure. This merging of functions reduces overall device complexity while achieving the goal of preventing carrier deterioration
3Loss of substance
If a discharge passage with discharge screw is added to the developing container, then surplus developer can be discharged, but the manufacturing complexity increases
Solution Approach 1:
The discharge passage is designed as a separate, modular component that can be independently manufactured and then integrated into the developing container. This segmentation allows for simplified manufacturing of the discharge passage using standard machining processes, reducing overall manufacturing complexity
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 configuration ensures stable and uniform developer supply, maintaining carrier charging performance and preventing surplus developer accumulation, thus enhancing the image forming process efficiency and reducing maintenance needs.
Implementation Method 1
a discharge screw that is formed to be continuous with an end portion of one of the first stirring conveyance member and the second stirring conveyance member, and that has a rotation shaft and a spiral blade provided on a peripheral surface of the rotation shaft
Implementation Method 2
The first stirring conveyance member and the second stirring conveyance member stir and carry the developer within the developing container. In the second conveyance chamber, the developer is conveyed by the second stirring conveyance member in a direction opposite to a direction in which the first stirring conveyance member conveys the developer
Implementation Method 3
a developer carrying member... which carries the developer supplied from the second stirring conveyance member
Data Source
AI summary
A developing device according to the present disclosure is provided with a developing container, a first stirring conveyance member and a second stirring conveyance member that stir and convey a developer within the developing container, and a developer carrying member that carries the developer. The developing container includes a discharge passage where a developer discharge port for discharging surplus developer within the developing container is formed. In the discharge passage, a discharge screw having a rotation shaft and a spiral blade is disposed. Within the discharge passage, at a portion on an upstream side of the developer discharge port in a developer discharge direction, there is provided a discharge regulating member that regulates discharge of the developer.