CIJ Stimulation Range Detection via Electrostatic Charge Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the optimal operating point in continuous ink jet printers are not fully satisfactory as they do not effectively characterize break-off quality, leading to potential operating points outside the functional stimulation range, and require complex and costly systems for testing.
Innovation Solution
A method involving generating specific sequences of charged and uncharged drops to measure charge variation using an electrostatic sensor, allowing for the determination of the actual stimulation range and optimal operating point under worst-case conditions, without altering existing printheads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If existing methods are used to determine the optimal operating point, then the printing operation can be maintained, but the break-off quality cannot be accurately characterized, leading to potential operating points outside the functional stimulation range
Solution Approach 1:
The patent replaces complex mechanical testing systems with an electrostatic sensing system. By measuring charge variations on drops passing through the stimulation field, the system accurately characterizes break-off quality without requiring mechanical measurement apparatus. This substitution enables precise determination of the functional stimulation range while simplifying the overall system.
Solution Approach 2:
The patent changes the measurement parameter from mechanical properties to electrical charge properties. By monitoring charge variations on ink drops as they pass through the stimulation field, the system can accurately determine break-off quality and identify the optimal stimulation range. This parameter change enables more precise measurement and control.
2Measurement precision
If complex testing systems are implemented to determine the stimulation range, then measurement accuracy improves, but system complexity and cost increase
Solution Approach 1:
The patent replaces complex mechanical testing systems with an electrostatic sensing system. By measuring charge variations on drops passing through the stimulation field, the system accurately characterizes break-off quality without requiring mechanical measurement apparatus. This substitution enables precise determination of the functional stimulation range while simplifying the overall system.
Solution Approach 2:
The ink drops themselves serve as the measurement probes. As drops pass through the stimulation field, their charge variations naturally indicate break-off quality. This self-service approach eliminates the need for separate, complex testing apparatus, as the printing medium itself provides the measurement information.
3Device complexity
If the stimulation range is not accurately determined, then system simplicity is maintained, but printing quality becomes unstable across temperature variations
Solution Approach 1:
The patent implements a feedback mechanism where charge variations on ink drops are continuously monitored. This feedback information is used to accurately determine the functional stimulation range and identify the optimal operating point. The system can then maintain stable printing quality across temperature variations by operating within the identified reliable stimulation range.
Solution Approach 2:
The patent performs preliminary characterization of the stimulation range before actual printing operations. By using electrostatic sensing to identify the optimal operating point and functional range in advance, the system ensures that subsequent printing operations will maintain stable quality across temperature variations without requiring complex real-time adjustments.
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 ensures robust and nominal printing quality across a large temperature range by accurately determining the break-off quality and optimal stimulation level, reducing system complexity and cost.
Implementation Method 1
measuring charge variation of a jet of non-deflected drops by passing in front of an electrostatic sensor
Implementation Method 2
made up of a piezoelectric ceramic placed in the ink, the ink jet breaks off at regular temporal intervals, corresponding to the period of the stimulation signal
Data Source
Figure 1~2c
Figure 3~4
Figure 5A~5C
AI summary
A method is described for determining the quality of a break-off of an ink jet of a CIJ printing machine, this method including: a) generating a first line of N1 drops, all charged by the charge means, at a same voltage V1, b) then generating at least one drop G1, charged by the charge means, at a second voltage (VG1), followed by at least one drop G2, charged by the charge means, at a third voltage (VG2) lower than V1, c) then generating a second line of N2 drops, all charged by the charge means, at a same voltage V2, d) measuring, using an electrostatic sensor, the charge variation of a non-deflected jet of drops including at least the first line of drops and the second line of drops, separated by the drops G1 and G2, during the passage of said jet in front of the sensor.