Balanced Flexural Resonator Structure for Low Energy Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flexural-vibration resonators suffer from vibrational energy losses and symmetry defects due to asymmetries caused by crystalline etching, leading to degraded quality factors and measurement biases in force sensors and gyrometers.
Innovation Solution
A resonator design with a vibrating portion having symmetrical extensions and a foot connection, featuring longitudinal slots and balanced momentum components, allowing for reduced vibrational energy loss and improved symmetry, utilizing monocrystalline piezoelectric materials like quartz.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If wet chemical etching is used to fabricate the resonator, then manufacturing simplicity and etching speed are improved, but symmetry defects and vibrational energy losses occur due to crystalline orientation asymmetries
Solution Approach 1:
The patent applies asymmetry by intentionally designing the resonator structure to compensate for the inherent asymmetry caused by wet chemical etching. The foot connection and extension geometries are specifically configured to counterbalance the etching-induced asymmetries, allowing the use of simple wet etching processes while achieving the required symmetry for high-quality factor operation.
2Device complexity
If the resonator structure is simplified for ease of manufacture, then production complexity is reduced, but vibrational energy losses increase due to asymmetries
Solution Approach 1:
The patent converts the harmful effect of etching asymmetries into a beneficial design feature. By analyzing the specific asymmetries introduced by wet etching, the design incorporates a foot connection and extension structure that transforms these asymmetries into balanced momentum components, thereby reducing vibrational energy losses while maintaining manufacturing simplicity.
3Manufacturing precision
If symmetrical extensions are added to compensate for etching asymmetries, then manufacturing precision is improved, but device complexity increases
Solution Approach 1:
The patent merges the compensation function into the existing resonator structure by integrating the foot connection and extension design with the primary resonating elements. This unified structure achieves symmetry compensation without adding separate compensation components, thereby improving manufacturing precision while limiting the increase in device complexity.
4Reliability
If the foot connection is optimized for dynamic balance, then quality factor is improved, but manufacturing precision requirements increase
Solution Approach 1:
The foot connection design incorporates geometric features that enable self-alignment and self-balancing during fabrication. The symmetrical extension geometry and foot configuration allow the structure to automatically compensate for minor manufacturing variations, achieving high quality factor performance without requiring extremely tight manufacturing tolerances.
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 resonator achieves high quality factors with minimal energy loss and improved symmetry, enhancing the precision and accuracy of force sensors and gyrometers by compensating momentum components and maintaining dynamic balance.
Implementation Method 1
the piezoelectric tensor of trigonal class crystals offers optimal coupling for deformation Syy, i.e. along the axis of the beam, with an electrical field Exx. For this, the flexural vibration of the beam is excited by a direct piezoelectric effect using electrodes which are located along the beam in order to generate the electrical field Exx, and to detect deformations Syy via electrical charges generated by an indirect piezoelectric effect on these same electrodes.
Data Source
AI summary
A resonator is suitable for reducing or suppressing a force transmitted by a vibrating portion of the resonator to a support part. To this end, the vibrating portion includes two extensions which are each meander shaped such that two segments of each extension have respective speed components that are oriented in opposite directions. Such a resonator, which is balanced, can advantageously be used within a rate gyro or a force sensor.


