Inkjet Printhead Nozzle Discharge Detection via Temperature Differential
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing inkjet printing technologies face challenges in accurately determining ink discharge failures in nozzles due to clogging or viscosity issues, leading to poor detection accuracy and increased apparatus size and cost.
Innovation Solution
A printing apparatus with temperature sensors integrated directly on the heater board, using a second voltage application to differentiate between normal and failed ink discharge states by analyzing temperature changes, and employing first and second-order differential processing to determine the ink discharge state effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a temperature detector is arranged below the heater to detect temperature drop, then the detection of discharge failure is simplified, but the detection accuracy degrades because the temperature drop phenomenon occurs upon contact of a very tiny ink droplet resulting in hard-to-detect small differences
Solution Approach 1:
The patent applies preliminary action by pre-heating the ink in the nozzle to a temperature higher than the boiling point before discharge. This creates a significant temperature difference between normal discharge (where hot ink contacts the detector) and discharge failure (where no ink contacts the detector), making the temperature change easily detectable and solving the accuracy problem while maintaining simple device structure
Solution Approach 2:
The patent changes the temperature parameter of the ink by pre-heating it above the boiling point. This parameter change creates a large temperature differential that is easily detectable, transforming the subtle temperature drop detection problem into a clear binary detection task between significant temperature changes (normal discharge) and no temperature change (discharge failure)
2Measurement precision
If a sensor for detecting ink flow temperature is arranged in the channel or nozzle, then ink flow detection is enabled, but the apparatus size increases and manufacturing cost rises
Solution Approach 1:
The patent makes the heater board serve multiple functions: it acts as both the heating element for ink discharge and the temperature detection sensor. By integrating the temperature detector into the heater board structure itself, the patent eliminates the need for separate sensors in the channel or nozzle, thereby maintaining detection capability while reducing apparatus size and cost
Solution Approach 2:
The patent merges the heater and temperature detector into a single integrated component (the heater board). This combination allows the same structure to perform both heating and sensing functions, eliminating the need for separate sensing components and reducing overall device complexity and cost
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 accurate and efficient determination of ink discharge failures in each nozzle, reducing apparatus size and cost while enabling quick recovery and complementary printing operations.
Implementation Method 1
a printhead including a heater which generates heat energy to discharge ink
Implementation Method 2
a temperature detection element which detects a temperature along with driving
Data Source
Figure 1
Figure 2A~2B
Figure 3
AI summary
An embodiment of this invention is directed to determination of the ink discharge state of a printhead capable of accurately determining the discharge state of each nozzle while suppressing increases in the size and cost of an apparatus. In the embodiment, the ink discharge state of a printing apparatus including a printhead including a heater for discharging ink and a temperature sensor, and a driving unit configured to drive the heater is determined as follows. It is controlled to drive the heater by applying the first voltage for discharging ink, and drive the heater by applying the second voltage enough not to discharge the ink. Whether ink is normally discharged or discharge failure has occurred is determined based on information obtained from detected plural temperatures in regard to the application timing of the second voltage.