Cleaning Blade Hardness Segmentation for Permanent Deformation

Solution Overview

Problem

Conventional cleaning blades for electrophotographic image forming apparatuses face challenges in maintaining high cleaning performance over time due to permanent deformation of the blade member, which affects contact pressure and cleaning efficiency.

Innovation Solution

A cleaning blade with a blade member having a stack structure formed with layers of elastic materials of different hardness levels, where the edge line portion is impregnated with a resin to increase hardness and the permanent elongation rate of the entire blade member is kept below 3.0%, preventing permanent deformation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the blade member is made with high hardness material to improve cleaning performance, then contact pressure is maintained, but permanent deformation occurs over time

Engineering Contradiction:

ImprovehardnessVSAvoidpermanent deformation

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The blade member is divided into two distinct layers: a hard edge layer for cleaning contact and a soft backup layer for structural support. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The blade member uses a composite structure combining a hard edge layer (high hardness for cleaning) and a soft backup layer (low hardness for flexibility). This composite material approach resolves the contradiction by integrating materials with complementary properties.

Inventive Principle:

Principle #40Composite materials

2Strength

If the edge line portion is impregnated with resin and coated with surface layer to increase hardness, then cleaning performance improves, but permanent deformation still occurs

Engineering Contradiction:

Improveedge line hardnessVSAvoidpermanent elongation rate

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The blade member is divided into two distinct layers: a hard edge layer for cleaning contact and a soft backup layer for structural support. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The blade member uses a composite structure combining a hard edge layer (high hardness for cleaning) and a soft backup layer (low hardness for flexibility). This composite material approach resolves the contradiction by integrating materials with complementary properties.

Inventive Principle:

Principle #40Composite materials

3Device complexity

If a single-layer blade member is used for simplicity, then structure is simple and cost is low, but permanent deformation occurs

Engineering Contradiction:

Improveblade structureVSAvoidpermanent deformation

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The blade member is divided into two distinct layers: a hard edge layer for cleaning contact and a soft backup layer for structural support. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The blade member uses a composite structure combining a hard edge layer (high hardness for cleaning) and a soft backup layer (low hardness for flexibility). This composite material approach resolves the contradiction by integrating materials with complementary properties.

Inventive Principle:

Principle #40Composite materials

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

The solution effectively improves cleaning performance by maintaining high contact pressure and preventing permanent deformation of the blade member, ensuring stable cleaning performance over a long period.

Implementation Method 1

the edge line portion is impregnated with a resin

Methodology Applied

Scientific EffectPolymerization: Photopolymerisation

Data Source

PatentEP3175301B1Cleaning blade, image forming apparatus, and process cartridge

Publication Date: 2025.06.18 RICOH CO LTD

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AI summary

A cleaning blade includes: a blade having plural layers formed with elastic materials having different degrees of hardness from each other, an edge line portion of the blade being brought into contact with a surface of a cleaning target performing surface movement to remove adhering matter from the surface of the cleaning target. A cleaning layer of the plural layers including the edge line portion is impregnated with a resin or is made of an elastic material having a high degree of hardness. A permanent elongation rate of the entire blade is set at 3.0% or lower.