Ink Circulation Flow Rate Control for Nozzle Clogging and Drying
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ink deterioration and drying issues in printing apparatuses are exacerbated by circulation, particularly when the flow rate is high, leading to clogged nozzles and reduced print quality.
Innovation Solution
The ink circulation method involves circulating the ink at a lower flow rate than during print mode when the printer is stopped, using a pressure regulation mechanism to maintain a negative pressure difference between the feed and return reservoirs, and selectively switching between heating and non-heating modes based on expected print intervals to prevent drying and deterioration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the ink is circulated at a high flow rate to prevent drying in the discharge head, then the drying of ink is suppressed, but the deterioration of ink is accelerated
Solution Approach 1:
The patent applies dynamics by switching between different circulation flow rates based on the printing state. During printing, a first circulation flow rate (higher) is used to prevent nozzle clogging, while during stopped printing, a second circulation flow rate (lower) is used to minimize ink deterioration. This dynamic adjustment resolves the contradiction between preventing drying and avoiding ink deterioration.
Solution Approach 2:
The patent changes the circulation flow rate parameter according to the printing state. By setting different flow rate values for printing and non-printing states, the system optimizes both nozzle protection and ink quality preservation, resolving the technical contradiction between these two requirements.
2Stability of the object's composition
If the ink is not circulated when printing is stopped to preserve ink quality, then ink deterioration is suppressed, but the ink may dry and clog the nozzle
Solution Approach 1:
The system dynamically adjusts the circulation flow rate based on whether printing is in progress or stopped. During stopped printing, a low flow rate is maintained to prevent nozzle clogging while minimizing ink deterioration, rather than completely stopping circulation or maintaining high flow rate.
Solution Approach 2:
During stopped printing, the system applies partial circulation (low flow rate) rather than full circulation (high flow rate) or no circulation. This partial action is sufficient to prevent nozzle clogging while being gentle enough to minimize ink deterioration.
3Stability of the object's composition
If heating is continuously applied to prevent ink deterioration, then ink quality is maintained, but energy consumption increases and may accelerate ink drying
Solution Approach 1:
The heating unit operates periodically rather than continuously. Heating is applied during printing to maintain ink quality and prevent deterioration, and stopped during stopped printing to save energy. This periodic operation resolves the contradiction between maintaining ink quality and reducing energy consumption.
Solution Approach 2:
The system applies heating in advance during printing operations to maintain ink quality, and stops heating when printing is stopped. This preliminary action ensures ink is protected during high-risk periods while avoiding unnecessary energy consumption during low-risk periods.
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 effectively suppresses ink deterioration and drying, reducing the need for frequent ink replacement and nozzle cleaning, while allowing for quick restarts and maintaining print quality.
Implementation Method 1
a pressure regulation mechanism that regulates a negative pressure difference between the feed-side reservoir and the return-side reservoir
Implementation Method 2
a heating unit that heats the ink, and a control unit that causes the heating unit to heat the ink when the print mode is performed
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The ink I is circulated along the circulation channel Wc at the low-speed flow rate V1 lower than that during the execution of the print mode when the print mode is stopped (Steps S107, S110). By circulatingly supplying the ink I to the discharge heads H in this way, the deterioration of the ink I can be also suppressed while the drying of the ink I is suppressed.