Developing Apparatus Capacitance Toner Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing developing apparatuses face challenges in accurately detecting the remaining developer amount due to scattering developer blocking detection light, leading to reduced accuracy in toner amount detection.

Innovation Solution

The apparatus incorporates a concave portion within the turning radius of the stirring member, with conductive members positioned to measure capacitance changes as toner passes through, ensuring accurate detection of the developer amount by applying voltage and detecting changes in output voltage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a stirring member is used to stir the developer inside the developer container, then the developer is well-mixed and conveyed, but the developer scatters and blocks the detection light, reducing detection accuracy

Engineering Contradiction:
Improvedeveloper mixing and conveyanceVSAvoidremaining toner amount detection accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The invention extracts the detection function from the main developer container by providing a separate detection container with its own detection light path. This separates the stirring function (in main container) from the detection function (in detection container), allowing the stirring member to operate without blocking the detection light, thus resolving the contradiction between effective mixing and accurate detection

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention introduces an intermediary mechanism where the stirring member periodically conveys developer from the main container to the detection container. This intermediary transfer allows the detection light to pass through a controlled amount of developer without being blocked by scattered particles, enabling accurate detection while maintaining effective mixing in the main container

Inventive Principle:
Principle #24Intermediary (Mediator)

2Device complexity

If detection light passes through the inside of the developer container to detect remaining toner amount, then the detection structure is simple, but scattering developer blocks the detection light causing reduced detecting accuracy

Engineering Contradiction:
Improvedetection structure simplicityVSAvoidremaining toner amount detection accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The invention segments the detection system into two separate containers: a main developer container for storing and mixing developer, and a detection container for optical measurement. This segmentation allows the detection light to pass through a controlled environment with minimal scattering, maintaining detection accuracy while keeping the overall structure relatively simple

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention extracts the detection function from the main developer container by providing a separate detection container with its own detection light path. This separates the stirring function (in main container) from the detection function (in detection container), allowing the stirring member to operate without blocking the detection light, thus resolving the contradiction between effective mixing and accurate detection

Inventive Principle:
Principle #2Taking out (Extraction)

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 allows for stable and accurate detection of the remaining toner amount, even when the developer scatters, preventing errors in toner replenishment timing.

Implementation Method 1

a first detecting portion and a second detecting portion for detecting an amount of the developer in use of capacitance

Methodology Applied
Scientific EffectCapacitance: Capacitance

Implementation Method 2

a conveying member that conveys the developer by rotation

Methodology Applied
Scientific EffectCentrifugal Force: Centrifugal Force

Data Source

PatentEP3062161B1Developing apparatus
Publication Date: 2024.06.12 CANON KK
  • EP3062161B1 patent drawingFigure 1
  • EP3062161B1 patent drawingFigure 2
  • EP3062161B1 patent drawingFigure 3

AI summary

A developing apparatus includes: a developing chamber that has a developer bearing member bearing developer; an accommodating chamber that has a concave portion and an opening and accommodates the developer under the developing chamber; a conveying member that conveys the developer by rotation; and a first detecting member and a second detecting member that detect an amount of the developer in use of capacitance, wherein a part of the concave portion is within a turning radius of the conveying member, the first detecting member is provided on a downstream side in a rotating direction of the conveying member relative to the concave portion, and the second detecting member is provided on an upstream side in the rotating direction of the conveying member relative to the concave portion.