Cooling Device Counterflow Heat Exchange for Image Formers

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing cooling devices in image forming apparatuses have poor cooling efficiency due to the warming of cooling water by sheets, which limits the effective cooling of sheets.

Innovation Solution

A cooling device with a feeding portion using endless belts and a pressing roller to sandwich and press sheets, combined with a flow passage-forming portion for cooling medium flow, enhancing contact with a cooling plate and improving cooling efficiency by maintaining a temperature difference between sheets and cooling water.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If cooling water flows through the flow channel from upstream to downstream in the sheet feeding direction, then the cooling device structure is simple, but the cooling efficiency is poor due to warming of cooling water by high-temperature sheets

Engineering Contradiction:

Improvecooling device structure simplicityVSAvoidcooling efficiency

Core Design Contradiction:

Ease of manufactureVSLoss of energy

Solution Approach 1:

The patent inverts the conventional cooling water flow direction by making it flow from downstream to upstream (opposite to sheet feeding direction). This allows cooler water to first contact the coolest part of the sheet and progressively cool hotter sections, preventing the cooling water from being warmed by high-temperature sheets before reaching the cooling section, thereby maintaining high cooling efficiency throughout the flow path.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes the flow direction parameter of the cooling water from the conventional upstream-to-downstream direction to a downstream-to-upstream direction. This parameter change ensures that cooling water with lower temperature contacts the sheet first at the downstream side (where sheet temperature is lower after initial cooling), maintaining a larger temperature difference and higher heat transfer efficiency throughout the cooling process.

Inventive Principle:

Principle #35Parameter changes

2Loss of energy

If cooling water flows through the flow channel, then heat exchange with sheets occurs, but the temperature difference between sheets and cooling water decreases reducing cooling effectiveness

Engineering Contradiction:

Improveheat exchange capabilityVSAvoidtemperature difference between sheet and cooling water

Core Design Contradiction:

Loss of energyVSTemperature

Solution Approach 1:

The patent inverts the cooling water flow direction to flow opposite to the sheet feeding direction. This inversion ensures that cooling water enters the cooling section from the downstream side where it can maintain a larger temperature difference with the sheet throughout the heat exchange process, preventing premature warming of the cooling water and sustaining effective cooling across the entire sheet surface.

Inventive Principle:

Principle #13The other way round (Inversion)

3Area of stationary object

If the cooling section is expanded to improve cooling coverage, then more sheet area is cooled, but manufacturing cost increases

Engineering Contradiction:

Improvecooling section areaVSAvoidmanufacturing cost

Core Design Contradiction:

Area of stationary objectVSEase of manufacture

Solution Approach 1:

The patent utilizes hydraulic flow of cooling water through a carefully designed flow channel system that extends the effective cooling length without proportionally increasing the cooling section area. By optimizing the flow path configuration and utilizing the fluid dynamics of cooling water, the system achieves enhanced cooling coverage and efficiency without requiring a linear increase in manufacturing cost.

Inventive Principle:

Principle #29Pneumatics and hydraulics

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 significantly improves cooling efficiency by ensuring consistent temperature differences and expanded cooling sections, allowing for efficient sheet cooling while preventing manufacturing cost increases.

Implementation Method 1

The cooling portion has a flow passage-forming portion forming a flow passage through which a cooling medium flows and cools the sheet via the first belt

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

The pressing roller is provided inside the second belt, faces the flow passage-forming portion via the second belt and the first belt, and presses the second belt onto the cooling portion

Methodology Applied

Scientific EffectThermal contact enhancement: Conduction (thermal)

Data Source

PatentUS9122210B2Cooling device and image forming apparatus

Publication Date: 2015.09.01 KONICA MINOLTA INC

AI summary

A cooling section has a flow passage-forming section for forming a flow passage through which a cooling medium flows and cools a sheet via a first belt. A pressing roller is provided inside a second belt, faces the flow passage-forming section via the second belt and the first belt, and presses the second belt onto the cooling section.