Liquid Ejection Head Cleaning via Segmented Wiping and Preliminary Ejection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In ink-jet recording devices, the volatilization of volatile components in recording liquids leads to increased viscosity near ejection orifices, causing reduced landing accuracy and potential ejection failures, especially in multicolor heads where color mixing during wiping results in incomplete discharge of color-mixed recording liquids, leading to reduced recording quality and increased maintenance time.
Innovation Solution
A cleaning method for liquid ejection heads that involves sequential wiping and preliminary ejection from one end of the array to the other, where preliminary ejection is started before completing the wiping of the entire ejection orifice forming-face to prevent color mixing and thickening, allowing for immediate resumption of recording operations with minimal liquid consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If wiping is performed on a multicolor-integrated head to remove recording liquid from the ejection orifice forming-face, then ejection characteristics are improved, but different colors of recording liquids mix on the ejection orifice forming-face causing color mixture
Solution Approach 1:
The ejection orifice forming-face is divided into multiple regions corresponding to different color ejection orifices. The wiping member is configured to wipe each color region separately and sequentially, preventing mixing of different colored recording liquids while maintaining effective removal of dried liquid from each region.
Solution Approach 2:
The wiping operation is performed as a preliminary action before recording, and the wiping member is designed to clear each color region in a specific sequence. This preliminary wiping removes accumulated dried liquid without causing color mixing, ensuring clean ejection orifices for subsequent recording operations.
2Object-generated harmful factors
If circulation of recording liquid is stopped during wiping to prevent color mixture, then color mixture is prevented, but thickening of recording liquid inside ejection orifices or pressure chambers proceeds making it difficult to eject recording liquid during preliminary ejection
Solution Approach 1:
Preliminary ejection is performed immediately after wiping each color region while the wiping member is still in position. This preliminary action discharges any color-mixed recording liquid from the ejection orifices before the member moves to the next color region, preventing thickening and ensuring ejection capability is maintained.
Solution Approach 2:
The system maintains continuous operation by performing preliminary ejection as an intermediate step within the wiping process itself, rather than stopping circulation entirely. This continuous action ensures recording liquid remains fresh and ejectable while still preventing color mixture through sequential region processing.
3Object-generated harmful factors
If preliminary ejection is performed after completion of wiping for the entire ejection orifice forming-face, then color-mixed recording liquid can be discharged, but the volatile component of recording liquid volatilizes and the color-mixed recording liquid is thickened by wiping making it difficult to eject
Solution Approach 1:
Preliminary ejection is performed as an intermediate preliminary action during the wiping process, specifically after wiping each individual color region. This timing ensures color-mixed liquid is discharged before volatilization and thickening can occur, maintaining ejection effectiveness.
Solution Approach 2:
The preliminary ejection process is segmented to occur after each color region wiping rather than after complete wiping of all regions. This segmentation allows timely discharge of color-mixed liquid from each region before it can thicken, ensuring continuous ejection capability.
4Productivity
If circulation of recording liquid is resumed after wiping and preliminary ejection, then recording operation can be resumed, but maintenance time increases and consumption of recording liquid for maintenance increases
Solution Approach 1:
The wiping and preliminary ejection operations are integrated as preliminary actions that occur during the maintenance cycle without requiring complete cessation of recording liquid circulation. This allows maintenance to be performed efficiently with minimal interruption to overall system operation and reduced liquid consumption.
Solution Approach 2:
Recording liquid circulation is maintained continuously throughout the wiping and preliminary ejection process rather than being stopped and restarted. This continuous circulation eliminates idle time, reduces maintenance duration, and minimizes recording liquid consumption while ensuring proper liquid refreshment in all chambers.
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 method effectively prevents color mixing and thickening, reduces maintenance time, and ensures high recording quality by discharging color-mixed liquids before viscosity increases, allowing for immediate resumption of recording operations with minimal liquid consumption.
Implementation Method 1
a wiping step of performing wiping to wipe the ejection orifice forming-face
Implementation Method 2
a preliminary ejection step of performing preliminary ejection of the recording liquid from the wiped ejection orifices
Implementation Method 3
the volatile component of a recording liquid in contact with the outside air via the ejection orifices volatilizes (evaporates) and the viscosity of the recording liquid located near the ejection orifices increases
Data Source
AI summary
A cleaning method of a liquid ejection head where recording element substrates having an ejection orifice forming-face having ejection orifice arrays which are aligned, and at least one array ejects a different recording liquid than another, includes wiping and preliminary ejection. In the wiping, a wiping member is caused to move along and wipe the arrays. In the preliminary ejection, before the wiping of the entire ejection orifice forming-face is completed, preliminary ejection from the wiped ejection orifices is started. The wiping and preliminary ejection are sequentially performed from a recording element substrate at one end to a recording element substrate at the other end.