Fixing Belt Reflecting Member Surface Roughness

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional fixing devices in electrographic image forming apparatuses experience uneven temperature distribution along the fixing belt due to the non-passing region having a higher temperature than the passing region, leading to inefficiencies in fixing toner images onto recording media.

Innovation Solution

The fixing device incorporates a reflecting member with distinct surface roughness on its reflecting parts to efficiently distribute radiant heat from a heat source across both the passing and non-passing regions of the fixing belt, preventing temperature disparities and ensuring uniform heating.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a heat source radiates heat to the fixing belt, then the passing region is heated effectively, but the non-passing region becomes overheated due to uneven temperature distribution

Engineering Contradiction:
Improvetemperature distribution uniformityVSAvoidheat distribution efficiency
Core Design Contradiction:
TemperatureVSLoss of energy

Solution Approach 1:

The reflecting member has different surface roughness for different regions: the first reflecting part (facing passing region) has smaller roughness for focused heat reflection, while the second reflecting part (facing non-passing region) has larger roughness for diffuse heat reflection. This local differentiation of surface properties enables precise control of heat distribution to different belt regions.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The invention changes the surface roughness parameter of the reflecting member to control heat reflection characteristics. By adjusting the roughness value, the reflection pattern changes from specular (smooth) to diffuse (rough), enabling control over where the reflected radiant heat reaches the fixing belt.

Inventive Principle:
Principle #35Parameter changes

2Loss of energy

If the reflecting member uses a smooth surface, then heat is reflected efficiently to the passing region, but the non-passing region receives insufficient heat control

Engineering Contradiction:
Improveradiant heat reflection efficiencyVSAvoidnon-passing region temperature control
Core Design Contradiction:
Loss of energyVSTemperature

Solution Approach 1:

The reflecting member is divided into two regions with different surface qualities: the first reflecting part maintains smoothness for efficient specular reflection to the passing region, while the second reflecting part has increased roughness to provide diffuse reflection that prevents overheating of the non-passing region.

Inventive Principle:
Principle #3Local quality

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 ensures that the non-passing regions of the fixing belt do not exceed the temperature of the passing regions, maintaining even temperature distribution and effectively fixing toner images onto recording media without overheating.

Implementation Method 1

The reflecting member is configured to reflect the radiant heat radiated from the heat source to an inner circumferential face of the fixing belt

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

The heat source is arranged at an inner circumferential side of the fixing belt and configured to radiate a radiant heat

Methodology Applied
Scientific EffectThermal radiation: Thermal Radiation

Data Source

PatentEP2950158B1Fixing device and image forming apparatus
Publication Date: 2021.04.28 KYOCERA DOCUMENT SOLUTIONS INC
  • EP2950158B1 patent drawingFigure 1
  • EP2950158B1 patent drawingFigure 2
  • EP2950158B1 patent drawingFigure 3

AI summary

A fixing device (18) includes a fixing belt (22), a pressuring member (23), a heat source (24) and a reflecting member (25). The fixing belt (22) is arranged rotatably around a rotation axis (A). The reflecting member (25) reflects the radiant heat radiated from the heat source (24). The fixing belt (22) has a passing region (51) and a non-passing region (52). Through the passing region (51), a recording medium passes. The non-passing region (52) is arranged outside the passing region (51) in a direction of the rotation axis (A). The reflecting member (25) has a first reflecting part (64) and a second reflecting part (65). The first reflecting part (64) is arranged at an inner circumferential side of the passing region (51). The second reflecting part (65) is arranged at an inner circumferential side of the non-passing region (52). Roughness of a face at the heat source (24) side of the second reflecting part (65) is larger than roughness of a face at the heat source (24) side of the first reflecting part (64) .