Line Printer Pulse Segmentation for Nozzle Omission Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing line printers face challenges in detecting nozzle omission issues without reducing printing speed, as methods like monitoring ink discharge state through residual vibration require slowing down the printing process, thereby decreasing the amount of printing per unit time.
Innovation Solution
A system that includes a nozzle, a pressure chamber, a piezoelectric element, a pulse generation unit, and a residual vibration detection unit, allowing for the application of drive and inspection pulses at different speeds to inspect the liquid discharge state without stopping the printing process, enabling detection of dot omission symptoms before they occur.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If residual vibration detection method is applied to inspect liquid discharge state, then nozzle omission can be detected early, but printing speed must be reduced which decreases amount of printing per unit time
Solution Approach 1:
The patent divides the pulse signal into two distinct segments: a drive pulse for normal printing operation and an inspection pulse for residual vibration detection. By segmenting the pulse function, the system can perform both printing and inspection without requiring the recording sheet to move at reduced speed, thus resolving the contradiction between detection reliability and printing productivity.
Solution Approach 2:
The inspection pulse is applied after the drive pulse in a predetermined timing sequence, allowing the system to perform inspection actions preliminarily during the printing process rather than requiring separate inspection phases that would slow down printing. This enables early detection of nozzle omission while maintaining normal printing speed.
2Measurement precision
If inspection pulse is applied continuously to detect liquid discharge state, then real-time monitoring is achieved, but printing efficiency decreases due to additional pulse cycles
Solution Approach 1:
The patent implements periodic inspection by applying the inspection pulse at specific intervals after each drive pulse, rather than continuously monitoring. This periodic action allows the system to maintain printing efficiency while achieving sufficient measurement precision for detecting liquid discharge abnormalities through residual vibration analysis.
Solution Approach 2:
Instead of continuous inspection, the system applies inspection pulses only at necessary intervals (partial action), which is sufficient for detecting nozzle omission while minimizing the impact on printing efficiency. The inspection is applied excessively in terms of detection thoroughness but selectively in terms of timing frequency.
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 allows for increased printing efficiency by maintaining high printing speeds while inspecting the ink discharge state, preventing throughput reduction and enabling early detection of potential issues.
Implementation Method 1
a piezoelectric element that is provided to correspond to the pressure chamber and to discharge liquid
Implementation Method 2
a residual vibration detection unit that detects change in an electromotive force of the piezoelectric element in accordance with residual vibration in the pressure chamber
Data Source
AI summary
There is provided a line printer including: a nozzle that discharges liquid; a pressure chamber that communicates with the nozzle; a piezoelectric element that is provided to correspond to the pressure chamber and to discharge liquid; a pulse generation unit that generates a drive pulse to discharge liquid from the nozzle and an inspection pulse to inspect a liquid discharge state; and a residual vibration detection unit that detects residual vibration in the pressure chamber, which occurs after the inspection pulse is applied to the piezoelectric element. The drive pulse is caused to be applied to the piezoelectric element and the inspection pulse is caused not to be applied to the piezoelectric element at a first printing speed. The drive pulse and the inspection pulse are caused to be applied to the piezoelectric element at a second printing speed. The second printing speed is slower than the first printing speed.