Developing Device Contact Member Pressure Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional image forming devices face challenges in efficiently cleaning residual toner from developing rollers due to variations in toner charging characteristics and heat exposure, leading to increased load torque requirements and larger device sizes.

Innovation Solution

The image forming device incorporates a developing device with a contact member that adjusts contact pressure based on toner charging characteristics, featuring a bent part with a varying bend ratio to effectively clean residual toner, and configures deformation amounts between rollers to optimize toner supply and cleaning efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the deformation amount between the developing roller and toner supply roller is increased to suppress failures of scraping residual developing toner, then the scraping ability is improved, but the load torque required to rotate the rollers increases

Engineering Contradiction:

Improvescraping ability of residual developing tonerVSAvoidload torque

Core Design Contradiction:

ReliabilityVSForce

Solution Approach 1:

The patent applies local quality by configuring different deformation amounts for different developing devices based on their specific conditions. Developing devices closer to the fusing device (exposed to more heat) are given larger deformation amounts to enhance scraping ability, while those farther away use smaller deformation amounts. This localized adjustment optimizes scraping performance without uniformly increasing load torque across all devices.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the deformation amount parameter individually for each developing device based on the charging characteristics of the toner and the thermal environment. By adjusting this physical parameter locally, the system achieves effective residual toner scraping without requiring a uniform increase in deformation amount that would raise overall load torque requirements.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the deformation amount between the developing roller and toner supply roller is increased to prevent print contaminants, then the cleaning efficiency is improved, but the device size increases

Engineering Contradiction:

Improveprevention of print contaminantsVSAvoiddevice size

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The patent implements local quality by applying different deformation amounts to different developing devices according to their specific operational conditions. Only the developing devices that require enhanced scraping capability (those closer to the fusing device or using highly charged toner) receive larger deformation amounts, while others maintain smaller deformation amounts. This selective approach prevents print contaminants effectively without requiring a uniform increase in device size.

Inventive Principle:

Principle #3Local quality

3Productivity

If the contact pressure is increased to improve toner supply ability, then the toner supply efficiency is improved, but the load torque increases

Engineering Contradiction:

Improvetoner supply efficiencyVSAvoidload torque

Core Design Contradiction:

ProductivityVSForce

Solution Approach 1:

The patent applies local quality by configuring contact pressure (deformation amount) differently for each developing device based on its specific needs. Developing devices require adjusted contact pressure according to the charging characteristics of their toner and their position relative to the fusing device, rather than using a uniform high contact pressure that would increase overall load torque.

Inventive Principle:

Principle #3Local quality

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 reduces the load torque required for rotating rollers, allows for a more compact device design, and prevents print contaminants by efficiently cleaning residual toner across different toner types.

Implementation Method 1

a contact member that contacts the developer carrier and exerts a contact pressure per unit area thereon, the contact pressure per unit area being based on charging characteristics of the developer being used

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Implementation Method 2

The contact member includes a bent part at a tip part thereof, the bent part contacting the developer carrier

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Data Source

PatentUS8670699B2Image forming device and developing device

Publication Date: 2014.03.11 OKI ELECTRIC INDUSTRY CO LTD

AI summary

A developing device that is provided in an image forming device that forms an image includes an image carrier on which an electrostatic latent image is formed; a developer carrier that is configured to form a developer image on a surface of the image carrier by attaching developer on the electrostatic latent image; and a contact member that is configured to contact the developer carrier. The contact member contacts the developer carrier and exerts a contact pressure per unit area thereon, the contact pressure per unit area being based on charging characteristics of the developer being used.