Head Chip Electrode Segmentation for Stray Capacitance Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In liquid jet recording devices, stray capacitance can vary the ejection speed of ink, leading to degraded image quality.
Innovation Solution
A head chip with an actuator plate having specific electrode configurations, including obverse and reverse surface electrodes of varying sizes, is used to minimize stray capacitance, achieved through a manufacturing method involving evaporation masks and grinding processes to form channels and electrodes on a piezoelectric substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional electrode configurations are used in the actuator plate, then manufacturing is simpler, but stray capacitance increases causing ejection speed variation and degraded image quality
Solution Approach 1:
The electrode is divided into multiple segments: a first electrode on the obverse surface, a second electrode on the reverse surface, and a third electrode connecting them. This segmentation allows each electrode portion to be optimized independently to reduce stray capacitance while maintaining manufacturability through standardized connection structures.
Solution Approach 2:
Different electrode portions are designed with different properties: the first and second electrodes have specific areas optimized for reducing stray capacitance, while the third electrode provides mechanical and electrical connection. This local optimization allows the electrode system to reduce overall stray capacitance without requiring complete redesign of all components.
2Reliability
If larger electrode areas are used to improve electrical connection, then connection reliability improves, but stray capacitance increases causing ejection speed variation
Solution Approach 1:
The electrode configuration transitions from a single-plane design to a three-dimensional structure spanning both obverse and reverse surfaces of the actuator plate. By distributing electrode areas across multiple dimensions and surfaces, the design achieves reliable electrical connection while minimizing the effective area contributing to stray capacitance.
Solution Approach 2:
The third electrode acts as an intermediary connecting the first electrode on the obverse surface to the second electrode on the reverse surface. This intermediate connection structure allows electrical continuity to be maintained while the electrode geometry is optimized to reduce stray capacitance between adjacent electrodes.
3Reliability
If electrode material coverage is increased to reduce stray capacitance, then image quality improves, but material costs and manufacturing complexity increase
Solution Approach 1:
The electrode system is segmented into three distinct portions that can be manufactured and positioned separately, then assembled. This segmentation allows each portion to be optimized for its specific function (capacitance reduction vs. connection) while using standard manufacturing processes for each component, reducing overall manufacturing complexity despite the sophisticated overall 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 solution effectively suppresses stray capacitance, improving image quality by reducing variations in ejection speed and power consumption while lowering costs associated with electrode materials.
Implementation Method 1
a piezoelectric substrate having an obverse surface and a reverse surface with a channel which extends in a predetermined direction and has a first opening on the obverse surface
Implementation Method 2
evaporating a conductive material on a sidewall of the channel from the first opening provided with the mask so as to form a first evaporation part
Implementation Method 3
grinding the reverse surface of the piezoelectric substrate so as to reach the channel, to thereby form a second opening shorter in length in the predetermined direction than the first opening
Data Source
Figure 1
Figure 2
Figure 3
AI summary
There are provided a head chip and a method of manufacturing the same, a liquid jet head, and a liquid jet recording device each capable of suppressing a stray capacitance to improve the image quality. The head chip according to an embodiment of the present disclosure is a head chip having an actuator plate adapted to apply pressure to liquid to jet the liquid. The actuator plate includes an obverse surface and a reverse surface, a channel extending in a predetermined direction and having a first opening provided to the obverse surface and a second opening which is provided to the reverse surface and is shorter in length in the predetermined direction than the first opening, and an electrode having an obverse surface side part disposed on a sidewall of the channel on the first opening side, and a reverse surface side part which is disposed on the sidewall closer to the second opening than the obverse surface side part and is one of equal to and larger than the obverse surface side part in size in the predetermined direction.