Temperature Sensor Correction for Heating Roller Deviation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing image forming apparatuses face challenges in achieving high-precision temperature control due to deviations in temperature data detected by noncontact thermistors, which vary with different control modes of the heat source.

Innovation Solution

An image forming apparatus that includes a heat source, a heating member, a temperature sensor, and a controller capable of applying specific functions (linear, quadratic, or higher-order polynomial functions) to correct temperature data, allowing the controller to switch functions based on the current control mode, ensuring accurate temperature control regardless of the heat source's operation mode.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a noncontact thermistor is used to detect the temperature of the heating roller, then the temperature can be measured without contact, but the detected temperature deviates from the actual temperature due to environmental conditions and control mode variations

Engineering Contradiction:

Improvetemperature detection accuracyVSAvoidtemperature data accuracy

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent applies parameter changes by switching between multiple correction functions based on the control mode. Each function is optimized for specific heat source operation conditions (e.g., warming-up, fixing, standby modes). The controller selects the appropriate function according to the current mode, thereby adapting the temperature correction parameters to match the actual thermal environment and eliminate deviations caused by different operational states.

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If the control mode for the heat source is switched among multiple modes, then the heat source can be regulated flexibly, but the temperature detection data varies depending on the control mode, causing deviation from actual temperature

Engineering Contradiction:

Improveheat source control flexibilityVSAvoidtemperature detection accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent implements dynamics by making the correction function selectable and changeable based on the control mode. Instead of using a fixed correction method, the system dynamically switches between multiple correction functions (first, second, third functions) according to the current heat source operation mode. This dynamic adaptation ensures that the temperature correction remains accurate across varying operational conditions while maintaining control flexibility.

Inventive Principle:

Principle #15Dynamics

3Device complexity

If a single correction function is used for temperature detection, then the system is simple, but it cannot accurately correct temperature deviations across different control modes

Engineering Contradiction:

Improvetemperature correction system complexityVSAvoidtemperature control accuracy

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent resolves this contradiction by changing the correction parameters (functions) based on the control mode. The system stores multiple correction functions with different characteristics and selects the appropriate function according to the current mode of heat source operation. This approach maintains reasonable system complexity while significantly improving temperature control accuracy across different operational states.

Inventive Principle:

Principle #35Parameter changes

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 enables high-precision temperature control by appropriately correcting temperature data detected by the thermistor, even when the control mode is switched, thereby maintaining accurate temperature regulation across different operation modes of the heat source.

Implementation Method 1

a temperature sensor disposed apart from the heating member to detect a temperature of the heating member

Methodology Applied

Scientific EffectThermal radiation: Thermal Radiation

Implementation Method 2

a heat source; a heating member heated by the heat source to fix a developer image on a recording sheet

Methodology Applied

Scientific EffectHeating: Heating

Data Source

PatentUS8594523B2Image forming apparatus with a temperature sensor disposed apart from a heating member

Publication Date: 2013.11.26 BROTHER KOGYO KK

AI summary

In an image forming apparatus, a temperature of a heating member heated by a heat source to fix a developer image on a recording sheet is detected by a temperature sensor disposed apart from the heating member. A controller controls the heat source based upon a temperature determined mathematically by application of a specific function to the temperature detected by the temperature sensor. In the controller, the specific function is switched among a plurality of functions according to a control mode which is switchable among a plurality of modes and in which operation of the heat source is regulated.