Inkjet Printhead Firing Pattern Control for Pigment Settling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet printers face inconsistent print performance due to changes in ink concentration over time, caused by pigment settling in the ink reservoir, leading to variations in ink droplet concentration.
Innovation Solution
An inkjet printing system that includes a fire count detection system, ink height calculation system, time period detection system, and ink concentration calculation system, which work together with a control module to adjust the firing pattern of the printhead based on the detected ink concentration, ensuring consistent dot coverage by adjusting the number of ink droplets ejected.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If ink is stored in a reservoir for long-term use, then the inkjet printhead can operate extended periods, but pigment settling occurs resulting in varying ink concentration
Solution Approach 1:
The system performs preliminary detection of ink concentration and calculates the required compensation droplets before executing the corrected firing pattern. This allows the system to proactively adjust for pigment settling rather than reacting to quality degradation after it occurs.
Solution Approach 2:
The system implements a feedback mechanism where ink concentration is detected, processed to determine compensation requirements, and used to adjust subsequent ink ejection patterns. This closed-loop control maintains consistent print quality despite long-term storage effects.
2Reliability
If the firing pattern is adjusted to compensate for ink concentration changes, then print performance consistency is improved, but the system complexity increases
Solution Approach 1:
The system changes operational parameters (firing pattern, number of droplets) based on detected ink concentration levels. By dynamically adjusting these parameters, the system maintains print quality without requiring complex hardware modifications.
Solution Approach 2:
The system replaces complex mechanical adjustment mechanisms with computational methods. Instead of physically adjusting the printhead or ink delivery system, software algorithms calculate and apply compensation patterns based on sensor data.
3Stability of the object's composition
If the number of droplets is adjusted to maintain dot coverage, then ink concentration consistency is improved, but the time required for printing increases
Solution Approach 1:
The system performs concentration detection and compensation calculations periodically rather than continuously, adjusting the firing pattern at appropriate intervals. This approach maintains ink consistency while minimizing interruptions to the printing process.
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 maintains consistent print performance by dynamically adjusting the firing pattern in response to changes in ink concentration, ensuring reliable and uniform ink droplet distribution on the print medium.
Implementation Method 1
The liquid ink is heated such that a rapid volumetric change occurs in the ink resulting from a liquid to vapor transition and, consequently, the ink is forcibly ejected from the printhead as an ink droplet onto a recording medium.
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
A method for controlling an inkjet printing system (500) including calculating a pigment concentration of ink ejected by the inkjet printhead (510) relative to an initial pigment concentration of the ink based on a determined height of ink in an ink reservoir (520) and a determined period of time since a last printhead activation. A firing pattern for the inkjet printhead (510) is determined based on the determined height, the determined period of time and the calculated relative pigment concentration to account for settling of ink stored in the ink reservoir (520).