Fluid-Ejection Device Media Tension and Spacing Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Moisture-related expansion effects in media during fluid ejection in roller-based fluid-ejection devices lead to unintended fluid ejection and potential damage to mechanisms due to media wrinkling or cockling, affecting image quality and device operation.

Innovation Solution

Adjusting the tension of the media and maintaining a minimal distance between fluid-ejection mechanisms and rollers by adjusting the spacing to prevent contact, while optimizing fluid ejection quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If fluid is ejected onto media in a roller-based fluid-ejection device, then image formation is achieved, but moisture-related expansion effects cause media to expand and wrinkle, leading to unintended fluid ejection locations and potential mechanism contact

Engineering Contradiction:

Improvefluid ejection accuracyVSAvoidmoisture-related expansion effects

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The patent applies preliminary anti-action by pre-adjusting the spacing between fluid-ejection mechanisms and rollers, and pre-adjusting media tension, to counteract the expansion effects of moisture before they cause harmful deviations. The controller infers expansion effects and adjusts spacing in advance to maintain minimal distance despite media expansion, preventing unintended fluid ejection locations and mechanism contact.

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The patent changes physical parameters (spacing between mechanisms and rollers, tension of media) in response to inferred moisture-related expansion effects. The controller adjusts these parameters dynamically based on the type of media and fluid, the area and density of fluid coverage, and geometry of the print job to compensate for expansion and maintain precise fluid ejection accuracy.

Inventive Principle:

Principle #35Parameter changes

2Manufacturing precision

If spacing between fluid-ejection mechanisms and rollers is reduced to maintain minimal distance, then fluid ejection quality is optimized, but media expansion due to moisture causes contact between mechanisms and media

Engineering Contradiction:

Improvefluid ejection qualityVSAvoidmechanism protection from damage

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent implements dynamics by making the spacing between fluid-ejection mechanisms and rollers adjustable rather than fixed. The controller dynamically adjusts spacing based on inferred moisture-related expansion effects, allowing the system to maintain optimal minimal distance for fluid ejection quality while preventing mechanism contact when media expands due to moisture absorption.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent applies feedback by having the controller continuously infer moisture-related expansion effects based on media and fluid properties, and adjusting spacing accordingly. This closed-loop approach ensures that spacing is optimized for fluid ejection quality while simultaneously preventing media contact with mechanisms, thus protecting reliability.

Inventive Principle:

Principle #23Feedback

3Manufacturing precision

If media tension is increased to minimize expansion effects, then fluid ejection accuracy is maintained, but media may become more susceptible to damage or deformation

Engineering Contradiction:

Improvefluid ejection accuracyVSAvoidmedia integrity

Core Design Contradiction:

Manufacturing precisionVSStrength

Solution Approach 1:

The patent changes the tension parameter of media in a controlled manner, adjusting it based on the type of media and fluid, and the specifics of the print job. This allows the system to maintain fluid ejection accuracy by counteracting expansion effects while avoiding excessive tension that could damage or deform the media, as the controller optimizes tension levels for each specific scenario.

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

Minimizes media expansion and contact with fluid-ejection mechanisms, ensuring accurate fluid placement and maintaining image quality, thereby mitigating issues caused by moisture-related expansion effects.

Implementation Method 1

a fluid-ejection mechanism (102) positioned to eject fluid onto a surface of the media (110)

Methodology Applied

Scientific EffectFluid ejection:

Implementation Method 2

the media (110) is to expand as a result of the fluid being ejected onto the media (110)

Methodology Applied

Scientific EffectMoisture-related expansion:

Data Source

PatentEP2419276B1Counteracting expansion effects of moisture on media within fluid-ejection device

Publication Date: 2017.01.18 HEWLETT PACKARD DEVELOPMENT COMPANY LP

AI summary

Expansion effects of moisture on media resulting from ejection of fluid by the fluid-ejection device onto the media within a print zone in accordance with a portion of a print job are inferred. In response to inferring the expansion effects of moisture on the media, an action is performed to counteract the expansion effects of moisture on the media.