Developing Roller Voltage Control for Pressing Force Deviation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing image forming apparatuses face difficulties in making adjustments during printing operations due to deviations in the pressing force applied by the pressing member, which affects the contact between the developing roller and the photosensitive drum, leading to inconsistent printing quality.

Innovation Solution

An image forming apparatus is designed with a toner cartridge and a drum cartridge that includes a developing roller and a photosensitive drum, respectively, where a pressing member applies a variable pressing force. The apparatus features a controller that reads the pressing force value from a memory and adjusts the voltage applied to the developing roller based on this value, ensuring optimal contact and printing quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the toner cartridge and drum cartridge are separately manufactured and shipped, then manufacturing efficiency and logistics are improved, but adjustment difficulty during printing operations increases due to deviations in pressing force

Engineering Contradiction:

Improvemanufacturing efficiencyVSAvoidadjustment difficulty

Core Design Contradiction:

Ease of manufactureVSEase of operation

Solution Approach 1:

The patent changes the electrical parameter (voltage) applied to the developing roller based on the pressing force value read from the drum memory. By adjusting the voltage parameter in response to pressing force deviations, the system compensates for manufacturing variations and maintains consistent developing performance without requiring mechanical adjustment.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the pressing member applies pressing force to the developing roller, then contact between developing roller and photosensitive drum is achieved, but printing quality becomes inconsistent due to pressing force deviation

Engineering Contradiction:

Improvecontact reliabilityVSAvoidprinting quality consistency

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent implements a feedback mechanism where the pressing force value stored in the drum memory is read by the controller, and the voltage applied to the developing roller is adjusted based on this feedback. This closed-loop control compensates for pressing force deviations and maintains consistent printing quality.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

Inventive Principle:

Principle #35Parameter changes

3Manufacturing precision

If voltage is applied to the developing roller to control developing bias, then printing quality can be optimized, but the system becomes more complex due to additional control mechanisms

Engineering Contradiction:

Improveprinting qualityVSAvoidcontrol mechanism complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent enables the system to self-adjust by having the controller automatically read the pressing force value from the drum memory and independently determine the appropriate voltage to apply to the developing roller. This self-service capability eliminates the need for manual adjustment while maintaining printing quality.

Inventive Principle:

Principle #25Self-service

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 allows for precise adjustments of the developing bias, enabling consistent printing quality even with variations in the pressing force, thereby improving the overall performance and reliability of the image forming apparatus.

Implementation Method 1

a developing roller (22) and a developing electrode (221). The developing roller has an outer circumferential surface. The developing electrode is electrically connected to the developing roller

Methodology Applied

Scientific EffectElectrostatic force: Electrostatics

Implementation Method 2

a pressing member (1B) configured to press the toner cartridge (2) toward the photosensitive drum (12) with a pressing force

Methodology Applied

Scientific EffectMechanical force: Mechanical Force

Data Source

PatentUS10585373B2Image forming apparatus capable of applying appropriate voltage to developing roller irrespective of deviation in pressing force of pressing member

Publication Date: 2020.03.10 BROTHER KOGYO KK

AI summary

An image forming apparatus includes: a casing; a toner cartridge; a drum cartridge; a main electrode; a first reading portion; and a controller. The toner cartridge is attachable to the drum cartridge and includes: a developing roller; and a developing electrode electrically connected to the developing roller. The drum cartridge is attachable to the casing and includes: a photosensitive drum; a pressing member; and a drum memory. The pressing member presses the toner cartridge toward the photosensitive drum so that an outer circumferential surface of the developing roller contacts an outer circumferential surface of the photosensitive drum. The drum memory stores a pressing force value indicating a pressing force to be applied by the pressing member. The controller is configured to perform: reading, through the first reading portion, the pressing force value from the drum memory; and applying a voltage to the main electrode based on the pressing force value.