Developing Unit Transmission Mechanism for Image Forming Apparatus

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing image forming apparatus configurations fail to transmit driving force effectively to the developing unit when the developing roller is separated from the photosensitive drum, disrupting the image forming process.

Innovation Solution

A mechanism is introduced to transmit the driving force from the apparatus main body to the developing unit, including a developing roller, even when it is separated from the photosensitive drum, using a transmission path that stabilizes the rotation of the photosensitive drum by applying rotation loads to the drum driving member.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the developing roller is separated from the photosensitive drum, then the developing unit can be moved for toner replenishment, but the driving force cannot be transmitted to the developing unit

Engineering Contradiction:
Improvetoner replenishmentVSAvoiddriving force transmission
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

A transmission member is introduced as an intermediary element to bridge the gap between the photosensitive drum and the developing roller. This transmission member engages with both components and transmits the driving force from the photosensitive drum to the developing roller even when they are separated, enabling both ease of operation for toner replenishment and reliable driving force transmission

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system is divided into separable components: the developing unit can be detached from the photosensitive drum for toner replenishment, while the transmission mechanism remains engaged to maintain driving force transmission. This segmentation allows independent access to the developing unit without affecting the overall system operation

Inventive Principle:
Principle #1Segmentation

2Ease of repair

If the developing roller is separated from the photosensitive drum, then maintenance becomes easier, but rotation stability of the photosensitive drum deteriorates

Engineering Contradiction:
ImprovemaintenanceVSAvoidrotation stability
Core Design Contradiction:
Ease of repairVSStability of the object's composition

Solution Approach 1:

The transmission member serves as a mediator that maintains the mechanical connection between the photosensitive drum and the developing unit during separation. This ensures that the photosensitive drum maintains its rotation stability through the engaged transmission mechanism while still allowing the developing unit to be removed for maintenance purposes

Inventive Principle:
Principle #24Intermediary (Mediator)

3Adaptability or versatility

If the developing unit is made movable for toner replenishment, then operational flexibility improves, but driving force transmission to the developing unit becomes problematic

Engineering Contradiction:
Improveoperational flexibilityVSAvoiddriving force transmission
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The system transitions from a static connected state to a dynamic separable state. The developing unit can be moved between an engaged position for normal operation and a separated position for toner replenishment, while the transmission member dynamically maintains the driving force connection throughout these transitions

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The transmission member acts as a flexible intermediary that accommodates the movable nature of the developing unit while ensuring continuous driving force transmission, enabling operational flexibility without compromising reliability

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP4191342B1Image forming apparatus and process unit
Publication Date: 2024.10.16 CANON KK
  • EP4191342B1 patent drawingFigure 1A
  • EP4191342B1 patent drawingFigure 1B
  • EP4191342B1 patent drawingFigure 2A

AI summary

A photosensitive member unit (25) including a photosensitive member (21) and a drive receiving portion (29) receiving a driving force for rotating the photosensitive member; a developing unit (30) joined to the photosensitive member unit so as to be movable relative to the photosensitive member unit between a first position in which a developing roller (31) is in contact with the photosensitive member and a second position in which the developing roller is spaced from the photosensitive member; and a transmission member (41, 241) transmitting the driving force to the developing unit, wherein the developing unit has a driven member driven by the transmission member, and the transmission member is configured to engage with the driven member to drive the driven member with the developing unit located in the first position, and to engage with the driven member to drive the driven member with the developing unit located in the second position.