Piezoelectric Panel Vibration Damping for Microphone Noise Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electronic devices that utilize piezoelectric elements for vibration-based sound transmission do not effectively address the vibration of panels attached to the housing, leading to inefficiencies in sound transmission and potential damage to the piezoelectric elements.

Innovation Solution

An electronic device design that incorporates a piezoelectric element attached to a panel, with a housing structure that includes a buffer and sound insulation to dampen vibrations, allowing the panel to deform and transmit sound without directly projecting the vibrating body, and using non-heat hardening adhesives or double-sided tape for attachment to prevent stress and enhance durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the piezoelectric element is attached directly to the panel on the housing, then the panel can vibrate to generate sound, but the vibration causes noise and echo to be picked up by the microphone

Engineering Contradiction:
Improvesound transmission efficacyVSAvoidnoise and echo pickup
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The housing is divided into functionally separated regions: a first region for the piezoelectric element and panel vibration, and a second region for the microphone. This spatial segmentation prevents vibration transmission from the panel to the microphone, eliminating noise and echo pickup while maintaining sound transmission efficacy.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A buffer member is introduced as an intermediary component between the panel and the microphone. This buffer absorbs and dampens vibrations, preventing them from reaching the microphone. The buffer acts as a mediator that allows the panel to vibrate freely for sound generation while protecting the microphone from harmful vibrations.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Device complexity

If the piezoelectric element is positioned closer to the center of the housing, then space is optimized, but the panel vibration may cause the device to be accidentally dropped

Engineering Contradiction:
Improvespace utilizationVSAvoiddevice stability during vibration
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The piezoelectric element is positioned asymmetrically in the housing, specifically closer to a first side than to a second side. This asymmetric positioning creates an offset center of gravity that prevents the device from being accidentally dropped during vibration, while still optimizing space utilization through strategic component placement.

Inventive Principle:
Principle #4Asymmetry

3Strength

If traditional heat-hardening adhesives are used to attach the piezoelectric element, then strong bonding is achieved, but stress builds up causing potential damage to the piezoelectric element

Engineering Contradiction:
Improvebonding strengthVSAvoidpiezoelectric element durability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The adhesive properties are changed by selecting non-heat hardening adhesives or double-sided tapes instead of traditional heat-hardening adhesives. This parameter change in the bonding material eliminates thermal stress buildup during curing while maintaining sufficient bonding strength, thereby preventing damage to the piezoelectric element and improving its durability.

Inventive Principle:
Principle #35Parameter changes

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 design enhances sound transmission efficacy by allowing the panel to vibrate effectively while reducing noise and echo pickup, protecting the piezoelectric element and making the device more user-friendly by preventing accidental dropping during vibration.

Implementation Method 1

a piezoelectric element; a panel, the piezoelectric element being attached thereto, the panel vibrating due to the piezoelectric element to generate a vibration sound transmitted by vibrating a part of a human body

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

a buffer for damping vibration transmitted from the panel to the microphone through the front face and/or the rear face

Methodology Applied
Scientific EffectVibration damping: Damping

Data Source

PatentEP2846556B1Electronic device
Publication Date: 2019.12.11 KYOCERA CORP
  • EP2846556B1 patent drawingFigure 1
  • EP2846556B1 patent drawingFigure 2
  • EP2846556B1 patent drawingFigure 3A~3D

AI summary

Provided is an electronic device that can be appropriately used as a type of electronic device that vibrates a panel attached to a housing. The electronic device includes a piezoelectric element, a panel, to which the piezoelectric element is attached, that vibrates due to the piezoelectric element to generate a vibration sound transmitted by vibrating a part of a human body, a housing supporting the panel with a first face, a microphone contained within the housing and disposed on a second face, and a buffer that damps vibration transmitted from the panel to the microphone through the first face and/or the second face, thereby reducing noise picked up by the microphone.