Piezoelectric Printing Device Inner Electrode Configuration

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Piezoelectric printing devices face challenges in achieving high printing resolution and fast throughput due to the large size of drop ejectors required for close nozzle spacing and the complexity of electrical interconnections, with electrodes on the outer surface leading to inefficient displacement and increased variability in drop volume and velocity.

Innovation Solution

A piezoelectric printing device configuration with electrodes on the inner surface of the piezoelectric plate, featuring a substrate with drop ejectors aligned in rows, where the piezoelectric plate is bonded to the substrate with an electrode layer including signal lines and ground traces for compact and efficient electrical interconnection, allowing for high-resolution and high-throughput printing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If electrodes are placed on the outer surface of the piezoelectric plate, then electrical interconnection is simplified, but displacement efficiency decreases and variability in drop volume and velocity increases

Engineering Contradiction:

Improveelectrical interconnectionVSAvoiddrop volume and velocity consistency

Core Design Contradiction:

Ease of operationVSManufacturing precision

Solution Approach 1:

The patent inverts the conventional electrode placement by moving electrodes from the outer surface to the inner surface of the piezoelectric plate. This inversion allows the electrodes to be positioned closer to the pressure chamber, improving displacement efficiency and drop consistency while electrical interconnection is maintained through extended conductive traces on the outer surface.

Inventive Principle:

Principle #13The other way round (Inversion)

2Productivity

If piezoelectric chamber wall area is increased to achieve useful drop volumes, then drop ejection efficiency improves, but nozzle spacing becomes limited and device size increases

Engineering Contradiction:

Improvedrop ejection efficiencyVSAvoiddevice size

Core Design Contradiction:

ProductivityVSArea of stationary object

Solution Approach 1:

The patent transitions from a conventional planar electrode configuration to a three-dimensional arrangement where electrodes are positioned on the inner surface of the piezoelectric plate. This dimensional change allows the electrodes to be closer to the pressure chamber center, achieving useful drop volumes with smaller chamber wall area and enabling closer nozzle spacing.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Reliability

If piezoelectric plate thickness is increased to reduce electrode variability effects, then manufacturing robustness improves, but displacement efficiency decreases

Engineering Contradiction:

Improvemanufacturing robustnessVSAvoiddisplacement efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent extracts the electrodes from the outer surface and relocates them to the inner surface of the piezoelectric plate. This extraction allows the use of thinner piezoelectric plates while maintaining displacement efficiency, as the electrodes are now positioned closer to the active deformation region, reducing the negative impact of plate thickness on efficiency.

Inventive Principle:

Principle #2Taking out (Extraction)

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 configuration enables efficient drop ejection with reduced variability in drop volume and velocity, facilitating compact and reliable electrical connections, and allowing for high-resolution and fast printing throughput.

Implementation Method 1

a piezoelectric element that causes the wall to deflect into the ink-filled pressure chamber when a voltage pulse is applied, so that ink is forced through the nozzle

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Data Source

PatentUS11285721B2Piezoelectric printing device with single layer inner electrode

Publication Date: 2022.03.29 SUZHOU RUIFA PRINTING TECH CO LTD

AI summary

A piezoelectric printing device includes a substrate and a piezoelectric plate. At least one row of drop ejectors is disposed along a row direction. Each drop ejector includes a nozzle in fluid communication with a pressure chamber that is bounded by side walls. The piezoelectric plate has a first surface that is disposed proximate to the first side of the substrate. A bonding layer is disposed between the piezoelectric plate and the substrate. An electrode layer is disposed between the first surface of the piezoelectric plate and the bonding layer. The electrode layer includes a signal line corresponding to each pressure chamber. Each signal line leads to a signal input pad. The electrode layer also includes ground traces disposed on both sides of each pressure chamber. The ground traces are electrically connected to at least one common ground bus that is electrically connected to at least one ground return pad.