Charging Roller Differential Rotation for Photoconductor Cleaning

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Image forming apparatuses face issues with the removal of discharge products such as NOx, which adhere to the photoconductor and cause defects in the developed image, requiring an effective method to clean these products without additional components.

Innovation Solution

The image forming apparatus employs a rotatable charging roller that rotates at a different peripheral velocity than the image carrier, using a fiber layer with a satin or twill weave to carry toner and remove discharge products by sliding against the photoconductor, thereby cleaning the surface without additional devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the charging member rotates at the same peripheral velocity as the image carrier, then the structure is simple and easy to control, but discharge products cannot be effectively removed from the photoconductor surface

Engineering Contradiction:

Improvedischarge products adhesionVSAvoidperipheral velocity difference

Core Design Contradiction:

Object-affected harmful factorsVSSpeed

Solution Approach 1:

The charging member is configured to rotate at a different peripheral velocity than the image carrier, creating a dynamic velocity difference that enables effective discharge product removal. This dynamic adjustment of rotational speed allows the charging member surface to slide relative to the photoconductor, generating the necessary mechanical action to remove adhered discharge products without requiring additional cleaning components.

Inventive Principle:

Principle #15Dynamics

2Object-affected harmful factors

If additional cleaning components are added to remove discharge products, then discharge product removal effectiveness improves, but the device complexity and component count increase

Engineering Contradiction:

Improvedischarge product removalVSAvoidnumber of components

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The charging member is designed to perform multiple functions: it not only charges the photoconductor surface but also removes discharge products through differential rotation. By making the charging member rotatable at a different peripheral velocity than the image carrier, the same component serves dual purposes, eliminating the need for separate cleaning mechanisms and reducing overall device complexity.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The charging member serves itself by using its own rotational motion to remove discharge products from the photoconductor. The differential rotation between the charging member and image carrier creates a self-cleaning effect where the charging member's movement relative to the photoconductor surface automatically removes adhered discharge products without requiring external cleaning devices.

Inventive Principle:

Principle #25Self-service

3Object-affected harmful factors

If the charging member rotates at a different peripheral velocity than the image carrier, then discharge product removal effectiveness improves, but the control complexity and synchronization requirements increase

Engineering Contradiction:

Improvedischarge product removalVSAvoidrotation speed control

Core Design Contradiction:

Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The system changes the rotational speed parameter of the charging member relative to the image carrier to achieve discharge product removal. By adjusting the peripheral velocity of the charging member to be different from that of the image carrier, the system creates the necessary conditions for effective cleaning while maintaining relatively simple control requirements through straightforward speed differential management.

Inventive Principle:

Principle #35Parameter changes

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 method effectively removes discharge products from the photoconductor, reducing image defects and minimizing the number of components required for cleaning, thus enhancing the image forming process efficiency.

Implementation Method 1

the charging member on which the toner from the image carrier is carried is caused to rotate at a peripheral velocity different from a peripheral velocity at which the image carrier rotates

Methodology Applied

Scientific EffectFriction: Friction

Data Source

PatentUS10175624B2Image forming apparatus including a charging member configured to rotate at a peripheral velocity different from a peripheral velocity at which an image carrier rotates

Publication Date: 2019.01.08 FUJIFILM BUSINESS INNOVATION CORP

AI summary

An image forming apparatus includes a rotatable image carrier that carries an image, a charging unit having a rotatable charging member that charges the image carrier, a developing unit that supplies a developer including at least toner to the charged image carrier, and a cleaning unit having a cleaning member that cleans a surface of the image carrier. At least when the image forming apparatus is not performing image formation, the charging member on which the toner from the image carrier is carried is caused to rotate at a peripheral velocity different from a peripheral velocity at which the image carrier rotates.