Developer Cartridge Replacement Timing via Agitator Rotation

Solution Overview

Problem

Conventional image-forming devices inaccurately determine when to replace developer cartridges due to the agitating member scattering developer unevenly, leading to incorrect assessments of remaining toner quantity, especially during low-volume printing operations.

Innovation Solution

An image forming device with a replaceable cartridge, a light-emitting element, a light-receiving element, and a determining unit that calculates a determination value based on the light signal after the agitator has rotated a prescribed number of times, ensuring accurate replacement timing by stabilizing toner distribution within the cartridge.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If the agitating member rotates frequently to agitate developer, then developer distribution is improved, but developer charging performance deteriorates due to excessive rubbing and agitation

Engineering Contradiction:

Improvedeveloper distribution uniformityVSAvoiddeveloper charging performance

Core Design Contradiction:

Stability of the object's compositionVSReliability

Solution Approach 1:

The system performs preliminary agitation by rotating the agitating member a first prescribed number of times before conducting the light reception measurement. This preliminary action ensures developer is sufficiently scattered throughout the cartridge, eliminating accumulation at the bottom, so that subsequent measurements accurately reflect actual developer quantity rather than distribution artifacts.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements continuous rotation of the agitating member during the measurement process, ensuring that developer remains uniformly distributed throughout the measurement period. This continuous action prevents new accumulation patterns from forming during measurement, maintaining measurement accuracy.

Inventive Principle:

Principle #20Continuity of useful action

2Reliability

If the agitating member rotates insufficiently, then developer charging performance is maintained, but developer distribution becomes uneven leading to inaccurate replacement timing determination

Engineering Contradiction:

Improvedeveloper charging performanceVSAvoiddeveloper quantity measurement accuracy

Core Design Contradiction:

ReliabilityVSMeasurement precision

Solution Approach 1:

The system performs preliminary agitation by rotating the agitating member a first prescribed number of times before conducting the light reception measurement. This preliminary action ensures developer is sufficiently scattered throughout the cartridge, eliminating accumulation at the bottom, so that subsequent measurements accurately reflect actual developer quantity rather than distribution artifacts.

Inventive Principle:

Principle #10Preliminary action

3Measurement precision

If the agitating member rotates continuously many times, then developer distribution uniformity is improved, but unnecessary rotations increase reducing productivity

Engineering Contradiction:

Improvedeveloper quantity measurement accuracyVSAvoidprinting efficiency

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The system performs preliminary agitation by rotating the agitating member a first prescribed number of times before conducting the light reception measurement. This preliminary action ensures developer is sufficiently scattered throughout the cartridge, eliminating accumulation at the bottom, so that subsequent measurements accurately reflect actual developer quantity rather than distribution artifacts.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent applies partial action by rotating the agitating member only a first prescribed number of times (sufficient for adequate scattering) rather than continuous excessive rotation. This partial agitation achieves the necessary developer distribution uniformity for accurate measurement while minimizing unnecessary rotations that would waste time and reduce printing productivity.

Inventive Principle:

Principle #16Partial or excessive action

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 solution accurately determines when to replace the developer cartridge, reducing unnecessary rotations of the agitator and developing roller, thereby maintaining toner charging performance and extending cartridge life while ensuring compact design.

Implementation Method 1

The light-emitting element is configured to emit a light toward the replaceable cartridge. The light-receiving element is configured to receive the light emitted by the light-emitting element through the replaceable cartridge to output a signal.

Methodology Applied

Scientific EffectLight absorption: Absorption (EM radiation)

Data Source

PatentUS8861992B2Image forming device with cartridge replacement alert system

Publication Date: 2014.10.14 BROTHER KOGYO KK

AI summary

An image forming device includes a replaceable cartridge, a light-emitting element, a light-receiving element, and a determining unit. The replaceable cartridge accommodates developer therein and includes an agitator and a developing roller rotatable together with the agitator. The light-emitting element is configured to emit a light toward the replaceable cartridge. The light-receiving element is configured to receive the light emitted by the light-emitting element through the replaceable cartridge to output a signal. The determination value is produced based on the signal. The determining unit is configured to determine whether or not the determination value is greater than a predetermined determination threshold upon the agitator having rotated continuously more than a first prescribed number of times. The determining unit determines that the replaceable cartridge should be replaced with a new one when the determination value is greater than the predetermined determination threshold.