Piezoelectric Liquid Discharge Control Using Capacitance Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid discharge systems, such as inkjet printers, face issues with a decrease in liquid discharge amount due to piezoelectric element displacement, which is not adequately addressed by existing methods that only correct drive signal voltage based on discharge times, as other factors like environmental conditions and voltage value also contribute to deterioration.
Innovation Solution
A liquid discharge system that includes a measurement circuit to measure the capacitance of piezoelectric elements, a determination circuit to assess their deterioration state, and a correction mechanism to adjust drive signal voltage based on capacitance to maintain consistent discharge, along with a life estimation and notification system to alert users when the element is nearing the end of its life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If voltage correction based on discharge times is implemented, then liquid discharge amount stability is improved, but deterioration caused by environmental factors and voltage variations cannot be adequately addressed
Solution Approach 1:
The patent implements a feedback mechanism where the capacitance value of the piezoelectric element is continuously monitored and used to adjust the drive signal voltage. The determination circuit compares the measured capacitance with reference values to detect deterioration, and the voltage correction applies compensatory adjustments to maintain consistent liquid discharge performance despite environmental changes, aging, or voltage variations.
Solution Approach 2:
The patent changes the correction parameter from discharge time count to capacitance value, which directly reflects the physical state of the piezoelectric element. By measuring capacitance and using it as the basis for voltage correction, the system adapts to actual element conditions rather than relying on operational history, thereby addressing multiple deterioration factors including environmental influences and voltage variations.
2Productivity
If piezoelectric element is repeatedly driven to form images, then productivity is improved, but displacement amount decreases causing deterioration in image quality
Solution Approach 1:
The patent performs preliminary detection of piezoelectric element capacitance before significant deterioration occurs. By continuously monitoring capacitance values and comparing them against reference values, the system identifies deterioration trends early and applies voltage corrections proactively, preventing image quality degradation before it impacts productivity.
Solution Approach 2:
The system establishes a feedback loop where capacitance measurements from the measurement circuit are fed to the determination circuit, which then adjusts the drive signal voltage accordingly. This closed-loop control ensures that even with repeated driving for high productivity, the displacement amount remains within acceptable ranges, maintaining image quality over extended operation 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 maintains discharge accuracy by accounting for various factors contributing to piezoelectric element deterioration, improving ink discharge consistency and user convenience through timely notifications and voltage adjustments.
Implementation Method 1
a piezoelectric element that is displaced based on a drive signal and discharges liquid
Implementation Method 2
a measurement circuit that measures a first capacitance of the piezoelectric element
Data Source
AI summary
A liquid discharge system including a piezoelectric element that is displaced in accordance with a drive signal and discharges liquid; a drive signal output circuit that outputs the drive signal; a measurement circuit that measures a first capacitance of the piezoelectric element; and a determination circuit that determines a deterioration state of the piezoelectric element based on the first capacitance.