Liquid Ejection Head Humidification via Preliminary Cleaning

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Solution Overview

Problem

The existing liquid ejection apparatuses face challenges in swiftly humidifying the ejection space due to the decrease in water content of the liquid contacting the cap and ejection face, which leads to inefficient humidification and potential clogging of ejection openings.

Innovation Solution

A method where the liquid contacting the ejection head and sealing mechanism is cleaned and removed before humid air is supplied, allowing for speedy humidification of the ejection space, and the air is circulated to reuse high humidity, reducing the consumption of the humidification source and preventing liquid from flowing into the air outlet opening.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If liquid is supplied to the ejection space without cleaning, then the ejection space is humidified, but the liquid with decreased water content absorbs water from the humid air, preventing speedy humidification

Engineering Contradiction:
Improvespeedy humidificationVSAvoidhumidification efficiency
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The cleaner removes liquid from the ejection space before the humid air supplier supplies humid air. This preliminary cleaning action prevents the degraded liquid from absorbing water from the humid air, thereby enabling speedy and efficient humidification of the ejection space.

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If liquid remains in the ejection space, then humid air can be supplied, but the liquid flows into the air outlet opening, compromising humidification functionality

Engineering Contradiction:
Improvehumidification operationVSAvoidhumidification functionality
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The cleaner removes liquid from the ejection space before humid air supply operation commences. This preliminary removal prevents liquid from flowing into the air outlet opening during humidification operation, thereby maintaining the reliability and proper functionality of the humidification system.

Inventive Principle:
Principle #10Preliminary action

3Stability of the object's composition

If liquid contacts the cap and ejection face, then the ejection space is formed, but water content decreases over time causing clogging

Engineering Contradiction:
Improveliquid water contentVSAvoidejection opening functionality
Core Design Contradiction:
Stability of the object's compositionVSReliability

Solution Approach 1:

The system periodically supplies humid air to the ejection space at predetermined intervals. This periodic humidification replenishes water content in the liquid that contacts the cap and ejection face, preventing viscosity increase and clogging of ejection openings while maintaining stable liquid composition.

Inventive Principle:
Principle #19Periodic 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 approach enables effective and rapid humidification of the ejection space, reducing the risk of clogging and maintaining the functionality of the humidification process by removing the reduced water content liquid and preventing its flow into the air outlet opening.

Implementation Method 1

An air-conditioning equipment (a humid air supplier) having an air channel including an air introduction opening and an air outlet opening formed in the cap humidifies the ejection space by supplying a humid air from the air introduction opening into the ejection space

Methodology Applied
Scientific EffectHumid air supply:

Implementation Method 2

If the liquid is not ejected from the ejection openings for a long time, a viscosity of the liquid near the ejection openings increases due to its vaporization, which may cause clogging of the ejection openings

Methodology Applied
Scientific EffectVaporization: Evaporation

Implementation Method 3

the liquid having contacted the liquid ejection head and the sealing mechanism at the area facing the ejection space is cleaned and removed before the humid air is supplied into the ejection space

Methodology Applied
Scientific EffectLiquid removal:

Implementation Method 4

the air is circulated to reuse high humidity, reducing the consumption of the humidification source

Methodology Applied
Scientific EffectAir circulation: Convection

Data Source

PatentEP2543512B1Liquid ejection apparatus and humid-air supply method
Publication Date: 2018.02.14 BROTHER KOGYO KK
  • EP2543512B1 patent drawingFigure 1
  • EP2543512B1 patent drawingFigure 2
  • EP2543512B1 patent drawingFigure 3

AI summary

A liquid ejection apparatus, including: a liquid ejection head (10) having an ejection face (10a) that has at least one ejection opening (14a) through which the liquid ejection head ejects liquid for forming an image on a recording medium, an ejection space being defined so as to face the ejection face; a sealing mechanism (50; 500) configured to selectively establish one of (i) a sealing state in which the sealing mechanism seals the ejection space from an outside space and (ii) an open state in which the sealing mechanism does not seal the ejection space from the outside space; an air introduction opening (31) configured to open in an area that faces the ejection space when the sealing mechanism is in the sealing state; a humid air supplier (60) configured to supply a humid air from the air introduction opening to the ejection space in the sealing state; a cleaner (70; 70, 9; 40) configured to clean the liquid contacting at least a part of an area of the liquid ejection head and the sealing mechanism, the area facing the ejection space; and a controller (100) configured to control the cleaner to clean the liquid before the supply of the humid air supplier.