Inkjet Recording Device With Bubble-Amount Feedback Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The generation of bubbles in inkjet recording devices due to dissolved air in the ink, which can lead to ejection failure, is influenced by temperature changes, necessitating effective countermeasures to maintain ejection performance.

Innovation Solution

An inkjet recording apparatus with a bubble countermeasure system that includes a bubble generation amount calculation means, a control device, and means for executing appropriate bubble countermeasures based on calculated bubble generation, utilizing a circulation degassing system to manage ink circulation and pressure to minimize bubble formation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If bubble countermeasure treatment is continuously applied, then ejection performance is maintained, but device complexity and operational cost increase

Engineering Contradiction:
Improveejection performanceVSAvoidbubble countermeasure system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system changes operational parameters (circulation pump operation, heater operation, pressure reduction valve operation) based on calculated bubble generation amounts. When bubble generation is low, these parameters are adjusted or stopped, reducing system complexity and operational cost while maintaining ejection performance when needed.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The bubble countermeasure treatment is made dynamic rather than static. The system continuously monitors temperature changes, calculates bubble generation amounts, and adjusts the countermeasure intensity accordingly. This dynamic approach allows the system to maintain reliability only when necessary, reducing overall complexity.

Inventive Principle:
Principle #15Dynamics

2Reliability

If temperature control is increased to prevent bubble generation, then ejection performance is maintained, but energy consumption increases

Engineering Contradiction:
Improveejection performanceVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

Instead of continuous temperature control, the system uses periodic action based on calculated bubble generation amounts. The heater and circulation pump are operated only when temperature changes indicate potential bubble generation, significantly reducing energy consumption while maintaining ejection performance when actually needed.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The system implements feedback control by continuously monitoring temperature changes, calculating bubble generation amounts, and adjusting heater operation accordingly. This feedback mechanism ensures energy is consumed only when necessary to prevent bubbles, resolving the contradiction between reliability and energy consumption.

Inventive Principle:
Principle #23Feedback

3Reliability

If degassing operation is performed frequently, then bubble generation is reduced, but productivity decreases

Engineering Contradiction:
Improveejection performanceVSAvoidprinting productivity
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The system applies partial action by performing degassing operations only to the extent necessary based on calculated bubble generation amounts. Instead of frequent full degassing operations that reduce productivity, the system applies just enough countermeasure treatment to maintain ejection performance, resolving the contradiction between reliability and productivity.

Inventive Principle:
Principle #16Partial or excessive action

4Reliability

If circulation pump operation is increased to reduce bubbles, then ejection performance is maintained, but energy consumption and device complexity increase

Engineering Contradiction:
Improveejection performanceVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The circulation pump operation is made dynamic based on real-time bubble generation calculations. The pump operates at variable speeds or is stopped entirely when bubble generation is low, reducing energy consumption while maintaining ejection performance when bubble generation is high. This dynamic control resolves the contradiction between reliability and energy consumption.

Inventive Principle:
Principle #15Dynamics

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 system effectively manages bubble generation by adjusting operations based on calculated bubble amounts, ensuring reliable ink ejection performance and reducing the need for costly components and operations.

Implementation Method 1

a circulation flow path 47 that circulates the liquid in the liquid tank; a circulation pump 67 that circulates the liquid in the liquid tank through the circulation flow path

Methodology Applied
Scientific EffectCirculation flow: Convection

Implementation Method 2

when the liquid tank is in a reduced pressure state, bubbles are generated from the liquid due to the dissolved air coming out of the liquid

Methodology Applied
Scientific EffectPressure reduction: Depressurisation

Data Source

PatentEP4628307A1Inkjet recording device
Publication Date: 2025.10.08 KYOCERA DOCUMENT SOLUTIONS INC
  • EP4628307A1 patent drawingFigure 1
  • EP4628307A1 patent drawingFigure 2
  • EP4628307A1 patent drawingFigure 3

AI summary

An inkjet recording apparatus (1) includes a recording head (21) which ejects a liquid; a bubble countermeasure means for executing a bubble countermeasure treatment determined as a countermeasure against bubbles generated in the liquid; a bubble generation amount calculation means for calculating an amount of bubbles generated from the liquid; and a control device (38) which relaxes the bubble countermeasure treatment when the amount of bubble generation calculated by the bubble generation amount calculation means is equal to or less than a predetermined amount.