Printhead Preliminary Ejection for Media Width Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Printing apparatuses face ejection defects due to ink evaporation and thickening in nozzles when switching between printing media of different widths, leading to incomplete preliminary ejections and potential defects.
Innovation Solution
A control method for a printing apparatus that conducts preliminary ejections on a wider medium than the next printed medium to maintain nozzle ejection state, especially after printing on a narrower medium, using a waste sheet preliminary ejection pattern to address unused nozzle regions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If preliminary ejection is conducted on a printing medium with the same width as the next printed medium, then nozzle ejection state is maintained, but ink is wasted on unused nozzle regions when switching from a narrower to a wider medium
Solution Approach 1:
The control unit conducts preliminary ejection on a printing medium with a width equal to or larger than the next printed medium's width before actual printing begins. This preliminary action ensures that all nozzles are properly warmed and tested in advance, preventing ejection defects while allowing ink to be deposited on a larger medium where unused portions can be discarded without affecting the final printed output quality.
2Loss of substance
If preliminary ejection is not conducted on unused nozzle regions, then ink waste is reduced, but ejection defects occur when switching between different media widths
Solution Approach 1:
The control unit performs preliminary ejection before printing on a medium with width equal to or larger than the next printed medium. This ensures that even nozzle regions that will not be used in the actual printing process are activated and warmed up in advance, preventing ejection defects when switching from narrower to wider media while minimizing ink waste by limiting preliminary ejection to only the necessary nozzle regions.
3Reliability
If preliminary ejection is conducted on a wider medium than the next printed medium, then all nozzle regions are maintained, but printing medium consumption increases
Solution Approach 1:
The control unit conducts preliminary ejection on a printing medium with a width equal to or larger than the next printed medium before actual printing. This ensures that all nozzles are properly warmed and tested in advance, preventing ejection defects while allowing ink to be deposited on a larger medium where unused portions can be discarded without affecting the final printed output quality.
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
Prevents ejection defects by ensuring appropriate nozzle maintenance through targeted preliminary ejections, even when switching between different media widths, thereby enhancing printing quality.
Implementation Method 1
a printing unit which prints images on a plurality of types of printing media having different widths in a first direction by ejecting an ink from a plurality of nozzles arrayed in the first direction
Implementation Method 2
there is a case where an ejection defect of a printing head is generated because water, a solvent, or the like which is a solvent component of an ink evaporates from nozzles of the printing head and thickens
Data Source
AI summary
In a case of conducting first printing on a first printing medium whose width in a first direction is a first width after second printing on a second printing medium whose width in the first direction is a second width smaller than the first width, a printing apparatus controls a printing unit to conduct a first preliminary ejection on a printing medium whose width in the first direction is equal to or larger than the first width after the second printing and before the first printing.