Inkjet Print Head Circulation Control for Discharge Port Blockage Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet printing apparatuses face issues with ink circulation times varying based on job content, leading to incomplete circulation and thickened ink accumulation around discharge ports, which can block normal ink discharge, especially when short circulation periods are repeated.
Innovation Solution
The printing apparatus includes a control unit that continues ink circulation for a predetermined time after a printing operation is completed, ensuring thorough dispersion of thickened ink and preventing blockages by extending the circulation period when short jobs are finished.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If circulation is terminated immediately after printing operation completion, then productivity is improved by reducing idle circulation time, but ink circulation completeness deteriorates leading to thickened ink accumulation and discharge port blockages
Solution Approach 1:
The circulation unit continues circulating ink for a predetermined period after the printing operation is completed, performing a preliminary action to disperse thickened ink before it can accumulate and block discharge ports. This ensures reliable ink discharge in subsequent printing operations while maintaining productivity by limiting the extension to a fixed predetermined period rather than indefinite circulation.
2Reliability
If circulation period is extended for short jobs, then ink circulation completeness is improved preventing blockages, but loss of time increases due to extended circulation beyond printing operation
Solution Approach 1:
The control unit dynamically adjusts the circulation period based on the printing operation time. When printing operations are completed in short periods, the circulation unit extends the circulation time by a predetermined period to ensure complete ink dispersion. This parameter change approach maintains ink discharge reliability while quantifying the time extension to prevent excessive idle circulation time.
3Productivity
If circulation is repeated in short periods, then productivity is improved by handling multiple short jobs quickly, but ink circulation completeness deteriorates as circulation time is insufficient in each cycle
Solution Approach 1:
The system implements periodic circulation actions where the circulation unit operates during printing operations and continues for a predetermined period after completion. This periodic action pattern ensures that even when multiple short jobs are processed quickly, each circulation cycle maintains sufficient duration to disperse thickened ink, preventing accumulation while allowing rapid job turnover through the structured start-stop rhythm.
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 solution effectively prevents ink blockages and ensures reliable discharge by maintaining ink circulation beyond the initial printing operation, even for short jobs, thereby maintaining print quality and apparatus functionality.
Implementation Method 1
a circulation unit configured to perform circulation of the liquid in a circulation passage including the pressure chamber
Data Source
AI summary
A printing apparatus includes a print head provided with a discharge port that discharges liquid and a pressure chamber filled with the liquid to be discharged from the discharge port, and configured to perform a printing operation by discharging the liquid from the discharge port based on print data, includes a circulation unit that performs circulation of the liquid in a circulation passage including the pressure chamber in a state where the printing operation is performed, and includes a control unit that controls the circulation unit to continue the circulation for a predetermined time after the printing operation is completed.