Drum Unit Pressing Member Prevents Cartridge Detachment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing configuration of drum cartridges in image forming apparatuses, which uses a lock lever to prevent the development cartridge from being improperly detached, results in a complex and larger number of parts, making it difficult to securely attach and detach the process cartridge without risk of impact-induced detachment.

Innovation Solution

A drum unit with a frame that includes a pressing member and a restriction section, allowing the development cartridge to move between a pressed and released state, where the pressing member contacts and restricts the pressed portion, preventing improper detachment by ensuring the development cartridge remains securely attached.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a lock lever is added to prevent development cartridge detachment, then reliability improves, but device complexity increases

Engineering Contradiction:

Improveprevention of improper detachmentVSAvoidnumber of parts

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The pressing member integrates two functions: the pressing section applies pressing force to the development cartridge, while the restriction section prevents detachment in the releasing direction. By combining these two previously separate functions (pressing and locking) into a single pressing member, the patent eliminates the need for a separate lock lever, thereby reducing part count while maintaining reliability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The pressing member is designed as a multi-functional component that simultaneously performs pressing action (through the pressing section) and restriction action (through the restriction section). This universal component replaces what would traditionally require multiple separate parts, simplifying the overall device structure while ensuring secure attachment

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Productivity

If the process cartridge is attached swiftly with great force, then productivity improves, but reliability deteriorates due to impact-induced detachment

Engineering Contradiction:

Improveattachment speedVSAvoidsecure attachment

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The restriction section is positioned to preemptively counteract the detachment force generated during swift attachment. When the development cartridge is rapidly inserted, the restriction section engages with the development cartridge's corresponding feature before impact can cause detachment, preventing the harmful effect in advance

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The restriction section acts as a preventive measure that is already in place before attachment occurs. It provides a mechanical constraint that absorbs and redirects the impact force during rapid attachment, preventing detachment before it can happen

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

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 configuration simplifies the process unit while effectively preventing the development cartridge from being improperly detached, ensuring secure attachment and reducing the risk of impact-induced detachment, thereby maintaining the integrity of the process cartridge during attachment and detachment.

Implementation Method 1

The drum cartridge includes a pressing member by which the development cartridge is pressed against the photoconductive drum. Specifically, the pressing member is urged by a compression spring.

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

a restriction section that is disposed in a different position from a position of the pressing section and configured to restrict movement of the pressed portion in a released direction

Methodology Applied

Scientific EffectMechanical Force: Mechanical Force

Data Source

PatentUS8995876B2Drum unit, development cartridge detachably attachable to the drum unit, and image forming apparatus having the drum unit and the development cartridge

Publication Date: 2015.03.31 BROTHER KOGYO KK

AI summary

A drum unit is provided, which includes a frame configured such that a development cartridge including a pressed portion is detachably attached thereto, and a pressing member. The development cartridge is movable between a pressed state where the pressed portion is pressed by the pressing member when attached to the frame and a released state where the pressed portion is released from pressing of the pressing member when the development cartridge is attached to the frame. The pressing member includes a pressing section that contacts and presses the pressed portion when the development cartridge is in the pressed state, and a restriction section configured to, when the development cartridge is in the pressing state, restrict movement of the pressed portion in a released direction, in which the pressed portion moves when the development cartridge moves from the pressing state to the released state.