Piezoelectric Vibration Device for IC Cards
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing IC cards with capacitors for storing induction electromotive force have a large number of components and fail to produce sufficient vibration when using a piezoelectric element.
Innovation Solution
A vibration device with a coil, a drive circuit generating a drive signal based on induction electromotive force, a piezoelectric element, and a metal plate with recesses to accommodate the piezoelectric element and circuits, reducing component count and enhancing vibration production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a capacitor is used to store induction electromotive force, then energy storage is achieved, but the number of components increases
Solution Approach 1:
The patent combines the energy storage function and vibration actuation function into a single integrated piezoelectric element. The piezoelectric element stores electrical energy and converts it to mechanical vibration, eliminating the need for separate capacitors and vibration motors, thus reducing component count while maintaining energy storage capability
Solution Approach 2:
The piezoelectric element serves multiple functions simultaneously: it acts as an energy storage device, a vibration actuator, and a mechanical driver. This multi-functionality resolves the contradiction by consolidating what would traditionally require separate components (capacitor + vibration motor) into a single element
2Device complexity
If a piezoelectric element is used instead of a vibration motor, then component count is reduced, but sufficient vibration cannot be produced
Solution Approach 1:
The patent utilizes the thickness dimension of the piezoelectric element by forming a recess in the card body that matches the thickness of the piezoelectric element. This allows the piezoelectric element to be properly positioned and apply its full vibrational force to the card body, overcoming the limitation of insufficient vibration while maintaining component reduction
Solution Approach 2:
The patent changes the physical parameters of the piezoelectric element selection and its mounting configuration to optimize vibration output. By selecting appropriate piezoelectric element specifications and positioning it within a precisely designed recess, the system achieves sufficient vibration strength despite using fewer components
3Force
If the piezoelectric element thickness is considered, then adequate vibration space is provided, but card body structure becomes complex
Solution Approach 1:
The patent segments the card body structure by forming a specific recess only in the region where the piezoelectric element is mounted. This localized structural modification provides the necessary space for the piezoelectric element thickness without requiring complex changes to the entire card body structure, thus resolving the contradiction between adequate vibration space and structural simplicity
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 allows for a compact, aesthetically maintained IC card that produces sufficient vibration by using a piezoelectric element effectively, reducing component count and ensuring moderate weightiness while enabling communication recognition through vibration.
Implementation Method 1
a coil; a drive circuit generating, based on induction electromotive force of the coil
Implementation Method 2
a piezoelectric element supplied with the drive signal
Data Source
AI summary
Disclosed herein is a vibration device that includes: a coil; a drive circuit generating, based on induction electromotive force of the coil, a drive signal having a predetermined frequency; a piezoelectric element supplied with the drive signal; and a metal plate having a recess. The piezoelectric element is accommodated in the recess of the metal plate and stuck to a bottom surface of the recess through an adhesive.