Piezoelectric Actuator with Multi-Directional Polarization for Inkjet Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional piezoelectric actuators for ink-jet heads have low driving efficiency, requiring high driving voltage to achieve desired jetting pressure, which increases electric power consumption.
Innovation Solution
A piezoelectric actuator design with a vibration plate, a piezoelectric layer, and multiple electrodes arranged to generate electric fields parallel to both the thickness and plane directions, allowing for different types of deformation with reduced electric potential differences, enhancing driving efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a conventional unimorph structure with a piezoelectric layer stacked on a vibration plate is used, then the actuator can generate deformation to apply jetting pressure, but high driving voltage is required which increases electric power consumption
Solution Approach 1:
The piezoelectric layer is divided into multiple independent piezoelectric elements (first, second, third, and fourth elements) arranged in a matrix pattern on the vibration plate. Each element can be independently controlled by corresponding electrodes, allowing segmented activation and more efficient energy utilization compared to the conventional unified unimorph structure.
Solution Approach 2:
Different regions of the vibration plate are equipped with piezoelectric elements having different polarization directions (thickness direction and plane direction) and controlled by different electrode patterns. This local differentiation allows optimized deformation control in different areas, improving overall energy efficiency while maintaining the required jetting pressure.
2Productivity
If a piezoelectric layer with electrodes on both surfaces is used to generate electric fields in thickness and plane directions, then driving efficiency is improved, but device complexity increases
Solution Approach 1:
Multiple electrode patterns (first, second, third, and fourth electrode patterns) are integrated on the vibration plate to simultaneously control multiple piezoelectric elements with different polarization directions. This merging of electrode functions allows complex multi-directional deformation control while simplifying the overall control architecture compared to separate independent systems.
Solution Approach 2:
The piezoelectric elements utilize both thickness-direction polarization and plane-direction polarization, adding a dimensional aspect to the deformation control. This multi-dimensional approach enables more efficient driving by exploiting deformation in multiple directions simultaneously, improving productivity while managing complexity through systematic electrode design.
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 actuator achieves significant deformation and improved driving efficiency at lower voltage differences, reducing electric power consumption and increasing jetting pressure effectiveness.
Implementation Method 1
a piezoelectric layer arranged on one surface of the vibration plate over the deformation acceptable section... the first portion of the piezoelectric layer is polarized in parallel to the thickness direction, and the second portion of the piezoelectric layer is polarized in parallel to the plane direction
Data Source
AI summary
A piezoelectric actuator includes a vibration plate which is joined to a flow passage unit to cover a pressure chamber formed in the flow passage unit, a piezoelectric layer arranged on the vibration plate, a first electrode arranged on the piezoelectric layer to face the pressure chamber, a second electrode arranged on the piezoelectric layer while being opposed to the first electrode, and a third area arranged in the remaining area of the piezoelectric layer opposed to the pressure chamber. A first portion of the piezoelectric layer interposed by the first and second electrodes is polarized in parallel to the thickness direction. A second portion of the piezoelectric layer disposed between the first and third electrodes in the plane direction, is polarized in parallel to the plane direction. Accordingly, there are provided the piezoelectric actuator having a high driving efficiency.