Piezoelectric Liquid Ejection Head for Synchronized Droplet Formation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing piezoelectric actuators in ink jet heads face challenges in efficiently controlling liquid ejection due to the limitations in timing and intensity of electric field application, leading to inconsistent droplet formation and ejection performance.
Innovation Solution
A liquid ejection head design featuring a piezoelectric actuator with distinct active regions polarized in the thickness direction, where the driver controls the intensity and timing of electric fields applied to these regions to synchronize their expansion and contraction periods, ensuring coordinated deformation for precise liquid ejection control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a voltage is applied to the piezoelectric layers and diaphragm to eject liquid, then liquid ejection is achieved, but the timing and intensity of electric field application cannot be precisely controlled leading to inconsistent droplet formation
Solution Approach 1:
The piezoelectric actuator is divided into multiple independent piezoelectric elements (first, second, third, and fourth elements) that can be controlled separately. This segmentation allows independent control of different regions of the diaphragm, enabling precise timing and intensity control of electric fields applied to each element, thereby achieving consistent droplet formation while maintaining ease of operation.
2Productivity
If the piezoelectric actuator expands and contracts to eject liquid, then liquid ejection is achieved, but the expansion and contraction timing of different regions does not overlap leading to inefficient ejection
Solution Approach 1:
The piezoelectric elements are driven with periodic electric fields that are synchronized in timing. The first and second piezoelectric elements expand and contract simultaneously, as do the third and fourth elements. This periodic coordinated action ensures that expansion and contraction timing of different regions overlaps, maximizing liquid ejection efficiency and eliminating time loss from timing mismatches.
3Ease of operation
If the piezoelectric actuator is designed with a single active region, then the structure is simple, but the control over liquid ejection timing and intensity is insufficient
Solution Approach 1:
Different piezoelectric elements are positioned to act on different local regions of the diaphragm (central region, peripheral region, outer region). Each element can be independently controlled with specific voltage intensity and timing, providing precise local control over liquid ejection. This local quality approach enables sophisticated ejection control while maintaining a relatively simple actuator structure composed of discrete piezoelectric elements.
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 enhances the precision and consistency of liquid droplet ejection, improving the quality and reliability of printing processes by aligning the expansion and contraction phases of the active regions, thereby optimizing droplet formation and ejection.
Implementation Method 1
The first active region is made of a piezoelectric member polarized in the thickness direction... When performing liquid ejection control, the driver controls intensity of a first electric field applied to the first active region in the thickness direction
Data Source
AI summary
A first active region is made of a piezoelectric overlaps a midsection of a pressure chamber when viewed in plan through a pressure applying surface. A second active region is made of a piezoelectric member closer than the first active region to the pressure applying surface. The second active region extends over both a peripheral section of the pressure chamber and an outer region located outside the pressure chamber when viewed in plan through the pressure applying surface. A driver controls intensity of a first electric field applied to the first active region and intensity of a second electric field applied to the second active region such that the time period over which the first active region contracts and the time period over which the second active region contracts overlap or coincide with each other. The first electric field is more intense than the second electric field.