Piezoelectric Element With Discontinuous Insulating Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing piezoelectric elements in automatic frequency control circuits for oscillating mechanical systems are complex and costly to manufacture, and they do not utilize the piezoelectric effect in a precise and optimum manner due to issues with charge polarity and electrode design.
Innovation Solution
A piezoelectric element with a balance spring made of piezoelectric crystal or ceramic, featuring at least two electrodes connected to an automatic frequency control circuit, and discontinuous insulating layers distributed in a predetermined angular periodicity to decouple electrodes and prevent charge cancellation, allowing for efficient charge collection and simple manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If piezoelectric films are deposited over the entire length of the balance spring, then frequency control coverage is improved, but manufacturing cost and complexity increase
Solution Approach 1:
The balance spring is divided into multiple discrete piezoelectric elements positioned at specific locations along its length, rather than applying a continuous film. Each element is independently controlled by separate electrodes, allowing selective activation based on the required frequency adjustment, thus reducing manufacturing complexity while maintaining effective control coverage.
Solution Approach 2:
Piezoelectric elements are strategically positioned at specific locations along the balance spring where they have maximum mechanical influence. This localized approach concentrates the piezoelectric effect where it is most needed, achieving effective frequency control with fewer elements and reduced manufacturing cost compared to full-length coverage.
2Reliability
If electrodes are placed on both sides of the piezoelectric material, then electrical connection is improved, but charge cancellation occurs reducing piezoelectric efficiency
Solution Approach 1:
One electrode is extracted from the opposing side configuration and repositioned to be coplanar with the other electrode on the same side of the piezoelectric material. This extraction from the traditional bipolar configuration eliminates the charge cancellation effect while maintaining adequate electrical connection through the modified geometry.
Solution Approach 2:
The electrode configuration transitions from a symmetric bipolar arrangement to an asymmetric coplanar arrangement. The electrodes are positioned asymmetrically on the same side of the piezoelectric material, creating an asymmetric electric field distribution that prevents charge cancellation and improves piezoelectric efficiency.
3Reliability
If complex electrode designs are used to improve charge collection, then piezoelectric performance is improved, but device complexity increases
Solution Approach 1:
Multiple electrode functions are merged into a simplified coplanar configuration. The electrodes serve both as electrical connection points and as the active piezoelectric actuation elements, eliminating the need for separate complex electrode structures and achieving efficient charge collection with reduced device complexity.
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 enables precise control of oscillation frequency with improved piezoelectric performance, overcoming the complexity and cost issues of existing designs by using a piezoelectric crystal or ceramic with strategically placed electrodes and insulating layers, allowing for efficient charge collection and easy design and manufacturing.
Implementation Method 1
The piezoelectric element may include the balance spring, on which it is known to deposit films of a (PZT type) piezoelectric material... the piezoelectric effect to be used in a precise and optimum manner
Implementation Method 2
a frequency adaptation signal is generated which, once applied to the piezoelectric element, allows a compressive or extension force to be generated on the element in order to brake or accelerate the oscillation
Data Source
AI summary
A piezoelectric element for an automatic frequency control circuit, the element including: a balance spring formed of a strip of piezoelectric material; at least a first electrode, configured to be connected to the circuit and being disposed on all or part of one side of the strip; at least a second electrode configured to be connected to the circuit and being disposed on all or part of another one side of the strip distinct from the one side on which the first electrode is disposed, the piezoelectric material being a piezoelectric crystal or a piezoelectric ceramic; and at least two discontinuous layers of an insulating material, each discontinuous layer being disposed on at least one side of the strip and separating the first electrode from the second electrode, the layers of insulating material being distributed on predetermined portions of the balance spring substantially forming arcs in a predetermined angular periodicity.