Image Forming Apparatus Humidity-Based Development Voltage Control
Solution Overview
Problem
In image forming apparatuses using a two-component development system, the deterioration of the developer due to varying usage environments and the number of sheets used leads to uneven charging and potential failures such as image fog or drum ghost.
Innovation Solution
The image forming apparatus includes a development device with a development voltage power supply that applies an alternating voltage superimposed on a direct voltage to the developer carrying member, and a controller that stepwise increases the frequency of the alternating voltage based on detected absolute humidity to maintain optimal development characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a two-component development system is used, then image forming capability is provided, but developer deterioration leads to uneven charging and image quality degradation
Solution Approach 1:
The patent changes the frequency parameter of the alternating voltage applied to the development device based on detected absolute humidity levels. By adjusting this electrical parameter in response to environmental conditions, the system compensates for developer deterioration and maintains consistent image quality throughout the developer's service life.
Solution Approach 2:
The patent implements a feedback control system where a humidity detection device monitors the absolute humidity environment, and the controller adjusts the alternating voltage frequency accordingly. This closed-loop feedback mechanism enables real-time compensation for environmental effects on developer performance, maintaining reliable image formation.
2Stability of the object's composition
If alternating voltage frequency is increased to compensate for high humidity, then charging uniformity improves, but energy consumption increases
Solution Approach 1:
The patent makes the alternating voltage frequency dynamic rather than fixed. The frequency is adjusted in real-time based on detected absolute humidity levels, allowing the system to optimize between charge uniformity and energy consumption by only increasing power when environmental conditions require it.
Solution Approach 2:
The system dynamically changes the frequency parameter of the alternating voltage based on environmental humidity detection. This parameter adjustment allows the system to maintain effective developer charging across varying humidity conditions while minimizing unnecessary energy consumption during optimal humidity ranges.
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 solution effectively suppresses image fog and drum ghost by adjusting the development voltage frequency in response to humidity changes, ensuring consistent image quality regardless of the usage environment and developer deterioration.
Implementation Method 1
The development voltage power supply applies, to the developer carrying member, a development voltage with an alternating voltage superimposed on a direct voltage
Implementation Method 2
The humidity detection device detects an absolute humidity around the development device
Implementation Method 3
The controller controls the development voltage power supply. The controller stepwise increases the frequency of the alternating voltage as the absolute humidity detected by the humidity detection device is increased
Data Source
AI summary
An image forming apparatus includes an image carrying member, a charging device, an exposure device, a development device, a development voltage power supply, a humidity detection device and a controller. The exposure device exposes the surface of the image carrying member charged by the charging device to form an electrostatic latent image. The development device includes a development container which stores a developer including a toner and a developer carrying member which supplies, to the image carrying member, the toner in the developer, and develops the electrostatic latent image into a toner image. The development voltage power supply applies, to the developer carrying member, a development voltage with an alternating voltage superimposed on a direct voltage. The humidity detection device detects an absolute humidity around the development device. The controller stepwise increases the frequency of the alternating voltage as the absolute humidity detected by the humidity detection device is increased.