FR2752972A1 - Acoustic signal assembly for credit card sized support for telephone system access - Google Patents

Acoustic signal assembly for credit card sized support for telephone system access Download PDF

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Publication number
FR2752972A1
FR2752972A1 FR9610859A FR9610859A FR2752972A1 FR 2752972 A1 FR2752972 A1 FR 2752972A1 FR 9610859 A FR9610859 A FR 9610859A FR 9610859 A FR9610859 A FR 9610859A FR 2752972 A1 FR2752972 A1 FR 2752972A1
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France
Prior art keywords
acoustic
assembly according
acoustic assembly
vibrating
blade
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Application number
FR9610859A
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French (fr)
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Individual
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Individual
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Priority to FR9610859A priority Critical patent/FR2752972A1/en
Publication of FR2752972A1 publication Critical patent/FR2752972A1/en
Withdrawn legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
    • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
    • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
    • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
    • G06K19/0723—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
    • G06K19/0728—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs the arrangement being an optical or sound-based communication interface
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
    • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
    • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
    • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
    • G06K19/077—Constructional details, e.g. mounting of circuits in the carrier
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/26—Devices for calling a subscriber
    • H04M1/27—Devices whereby a plurality of signals may be stored simultaneously
    • H04M1/274—Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc
    • H04M1/2745—Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc using static electronic memories, e.g. chips
    • H04M1/275—Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc using static electronic memories, e.g. chips implemented by means of portable electronic directories

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  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Piezo-Electric Transducers For Audible Bands (AREA)

Abstract

The assembly is intended for electronic devices which are less than or equal to 1.2mm in thickness and is able to generate acoustic signals in the frequency range compatible with their transport over a telephone network. It comprises a vibrating plate which is made of a piezoelectric material and is mounted directly and solidly on a substrate. The plate may be positioned parallel to the longest axis of the support in order to be subject to the minimum mechanical constraint. The acoustic device is coated with a thin layer of protective material to seal it completely and protect it against liquids and any oxidising substances. In an alternative arrangement, several plates may be used with each dedicated to a particular frequency range.

Description

7 Montage acoustique de surface linéaire pour générateur acoustique
La présente demande de brevet concerne les cartes de visite électroniques et les systèmes authentifieurs acoustiques.7 Linear surface acoustic mounting for acoustic generator
The present patent application concerns electronic business cards and acoustic authenticator systems.

En effet, il existe à ce jour divers produits et procédés permettant la fabrication de petits dispositifs de la taille d'une carte de crédit, sauf en épaisseur, qui permettent de composer soit un numéro de téléphone, soit une séquence d'authentification, soit les deux. Le principe en est le suivant: le dispositif comporte un circuit électronique capable de générer des signaux acoustiques désignés suivant l'abréviation DTMF (Dual Tone Multifrequency en anglais, fréquence vocale en français) selon la norme internationale CCITT Q23. Il comporte en outre un transducteur acoustique, avec sa cavité résonnante, une pile, de la mémoire pour permettre la composition automatique d'un numéro de téléphone lorsque l'on colle la partie acoustique du dispositif contre le micro d'un combiné téléphonique, et dans le cas de dispositifs authentifier, une unité de calcul permettant le calcul et l'envoi du résultat de ce calcul de manière acoustique, via le micro d'un combiné téléphonique.Indeed, to date there are various products and methods allowing the manufacture of small devices the size of a credit card, except in thickness, which make it possible to dial either a telephone number, or an authentication sequence, or both. The principle is as follows: the device comprises an electronic circuit capable of generating acoustic signals designated according to the abbreviation DTMF (Dual Tone Multifrequency in English, voice frequency in French) according to the international standard CCITT Q23. It further comprises an acoustic transducer, with its resonant cavity, a battery, memory to allow automatic dialing of a telephone number when the acoustic part of the device is glued against the microphone of a telephone handset, and in the case of authenticate devices, a calculation unit allowing the calculation and the sending of the result of this calculation acoustically, via the microphone of a telephone handset.

Le principe général de ces dispositifs est dans le domaine public. Bien que souvent annoncé, l'objectif dimensionnel, qu'est la carte de crédit dans son épaisseur ( soit de l'ordre de 0, 8 mm ) n'a jamais atteint avec ce genre de dispositif et ce , dû essentiellement au problème que pose l'acoustique dans cette épaisseur.The general principle of these devices is in the public domain. Although often announced, the dimensional objective, which is the credit card in its thickness (ie of the order of 0.8 mm), has never been achieved with this kind of device and this, mainly due to the problem that poses the acoustics in this thickness.

L'objet premier de la présente demande de brevet concerne la partie acoustique de ces dispositifs, à savoir permettre l'intégration ( avec un objectif de coût faible ) d'un système acoustique complet dans une épaisseur inférieur ou égale à 0,8 mm.The primary object of the present patent application relates to the acoustic part of these devices, namely to allow the integration (with a low cost objective) of a complete acoustic system in a thickness less than or equal to 0.8 mm.

Ce système acoustique devant générer de manière fiable l'ensemble des fréquences compatibles avec la norme CCITT Q23.This acoustic system must reliably generate all frequencies compatible with the CCITT Q23 standard.

Néanmoins, l'objectif de fiabilité acoustique n'est pas dans ce cadre, suffisant. En effet, les contraintes mécaniques liées à l'usage des cartes de crédit sont assez particulières : celles ci résident en général dans un portefeuille, lui même dans certains cas mis dans la poche arrière d'un pantalon. Ce qui implique que l?on s'assied sur ces cartes de crédit assez souvent. Une carte de crédit ne comporte pas de dispositif acoustique ou électronique, sauf en ce qui concerne les cartes à puces.However, the objective of acoustic reliability is not sufficient in this context. Indeed, the mechanical constraints linked to the use of credit cards are quite specific: these generally reside in a wallet, itself in some cases put in the back pocket of pants. Which implies that one sits on these credit cards quite often. A credit card does not have an acoustic or electronic device, except for smart cards.

les contraintes subies sont de type: gradient température, torsion, pliage compression, chute) et ont conduit à établir un ensemble de normes auxquelles doivent satisfaire les cartes à puces ( norme ISO). Dans le but de fabriquer des dispositifs générant des signaux acoustiques tels que décrits plus haut, au format carte de crédit, et plus particulièrement dans une épaisseur inférieure ou égale à 1,2 mm, ces dispositifs subiront le même type de contraintes, tout étant par principe, plus fragiles que des cartes à puces, dont la partie électronique ne dépasse pas 100 mu2 . the constraints undergone are of the type: temperature gradient, torsion, folding compression, fall) and have led to the establishment of a set of standards which chip cards must meet (ISO standard). In order to manufacture devices generating acoustic signals as described above, in credit card format, and more particularly in a thickness less than or equal to 1.2 mm, these devices will be subject to the same type of constraints, all being by in principle, more fragile than smart cards, the electronic part of which does not exceed 100 mu2.

L'objectif second de la présente invention concerne la tenue mécanique de la partie acoustique. a sensibilité des dispositifs électroniques aux liquides et à l'oxydation est très forte.The second objective of the present invention relates to the mechanical strength of the acoustic part. The sensitivity of electronic devices to liquids and to oxidation is very high.

L'objectif troisième de la présente invention concerne tant la protection du dispositif acoustique que l'électronique qui le commande des atteintes des liquides et substances oxydantes.The third objective of the present invention concerns both the protection of the acoustic device and the electronics which control it from damage to liquids and oxidizing substances.

L'objet de la présente invention consiste en la réalisation d'un dispositif permettant la génération de signaux acoustiques sur une surface plane. de très faible épaisseur et de faible sensibilité au contraintes mécaniques énoncées plus haut, dénommé ici:
Montage acoustique linéaire de surface. Pour cela, nous allons utiliser une lame vibrante suivant la figure 1. Cette lame vibrante est directement montée solidaire de la surface plane, sans aucun interstice. Cette lame peut être une lame piezzo électrique classique, un revêtement de type Pvdf, ou encore une lame métallique ou d'un matériau autre, accouplée à un dispositif la faisant vibrer, elle est de largeur faible (quelques mm).The object of the present invention consists in the production of a device allowing the generation of acoustic signals on a flat surface. very thin and of low sensitivity to the mechanical stresses stated above, called here:
Linear acoustic surface mounting. For this, we will use a vibrating blade according to Figure 1. This vibrating blade is directly mounted integral with the flat surface, without any gap. This blade can be a conventional piezoelectric blade, a Pvdf type coating, or even a metal blade or of another material, coupled to a device causing it to vibrate, it is of small width (a few mm).

l'effet désiré, à savoir la génération signal acoustique est produit par le mouvement appliqué par la lame vibrante à l'ensemble de la surface plane. puisque celle-ci l'entrame, via le montage qui la rend solidaire de l'ensemble (Figure 2 ).the desired effect, namely the acoustic signal generation, is produced by the movement applied by the vibrating blade to the entire flat surface. since the latter begins, via the assembly which makes it integral with the assembly (Figure 2).

Le substrat dont elle est solidaire présentant quant à lui les caractéristiques suivantes: pas de fréquence de résonance dans le spectre de fréquence acoustique que la lame produit et une rigidité mécanique compatible avec sa mise en vibration à ces mêmes fréquences (c'est le cas de nombreuses substances plastiques ).The substrate with which it is integral has, for its part, the following characteristics: no resonance frequency in the acoustic frequency spectrum that the blade produces and a mechanical rigidity compatible with its setting in vibration at these same frequencies (this is the case of many plastic substances).

La surface plane vibrant dans son ensemble constitue un amplificateur acoustique de la lame vibrante et donc un haut parleur plat.The entire vibrating planar surface constitutes an acoustic amplifier of the vibrating blade and therefore a flat speaker.

Le montage linéaire de surface suivant figure 1, présente l'avantage d'être insensible à une large plage de contraintes mécaniques qui pourraient être appliquées à cette surface plane (torsions, pliage
En effet, un pliage, ou bombage selon figure 3, ne fera l'objet d'aucune atteinte à la lame vibrante, par ailleurs solidaire du substrat.The linear surface mounting according to FIG. 1 has the advantage of being insensitive to a wide range of mechanical stresses which could be applied to this flat surface (twists, folding
Indeed, a folding, or bending according to Figure 3, will not be subject to any damage to the vibrating blade, which is also integral with the substrate.

Une torsion selon la figure 4, appliquera à la lame une très légère torsion extrêmement limitée par le fait que la lame est montée longitudinalement au centre de la surface, et donc selon l'axe de moindre contrainte.A twist according to Figure 4, will apply to the blade a very slight twist extremely limited by the fact that the blade is mounted longitudinally in the center of the surface, and therefore along the axis of least stress.

La compression n' a aucun effet sur la lame, puisque le dispositif dans son ensemble ne comporte pas de cavité résonnante et donc pas de possibilité de détruire le système en compressant la lame vibrante dans la cavité résonnante.Compression has no effect on the blade, since the device as a whole does not have a resonant cavity and therefore no possibility of destroying the system by compressing the vibrating blade in the resonant cavity.

Les contraintes de température (dans la gamme normale d'usage de ce genre de dispositif, soit environ -lO0C à +450C) sont essentiellement électroniques, et ne concernent donc pas directement l'unité de génération acoustique. The temperature constraints (in the normal range of use of this kind of device, ie approximately −10 ° C. to + 450 ° C.) are essentially electronic, and therefore do not directly concern the acoustic generation unit.

le montage de surface linéaire présente l'avantage de ne pas nécessiter la présence de trous sur l'une des faces de la surface plane pour générer des signaux acoustiques et donc d'être étanche aux liquides, substances oxydantes et poussières, et par la même de présenter une grande sécurité d'utilisation ( à cet effet, la lame vibrante est noyée dans le substrat, ou affleurante avec une couche de protection ).the linear surface mounting has the advantage of not requiring the presence of holes on one of the faces of the flat surface to generate acoustic signals and therefore of being impermeable to liquids, oxidizing substances and dust, and by the same to present a great safety of use (for this purpose, the vibrating blade is embedded in the substrate, or flush with a protective layer).

Enfin, le principe de montage acoustique de surface linéaire peut lui même peut être agrémenté de plusieurs lames, afin de mieux générer l'ensemble du spectre acoustique qui est visé : deux ou trois lames de longueur adaptée aux fréquences à reproduire, voir montage selon la figure 5.Finally, the principle of acoustic mounting of linear surface can itself be embellished with several blades, in order to better generate the whole of the acoustic spectrum which is targeted: two or three blades of length adapted to the frequencies to be reproduced, see assembly according to the figure 5.

Détail des figures
Figure 1 (vues de face et de profil )
(1) lame vibrante (vue de face)
(2) Objet plan de faible épaisseur
(3) Lame vibrante montée solidairement à l'objet plan de faible épaisseur.Detail of the figures
Figure 1 (front and side views)
(1) vibrating blade (front view)
(2) Thin planar object
(3) Vibrating blade mounted integrally with the planar object of small thickness.

(4) épaisseur comprise entre 0,5 mm et 1,2 mm. (4) thickness between 0.5 mm and 1.2 mm.

(5) objet plan de faible épaisseur
Figure 2:
Vue exagérée d'une courbure transversale appliquée par la lame à l'ensemble
de la surface lors de l'application d'un signal électrique à la lame. La surface
ainsi pilotée par la lame sert d'amplificateur acoustique au système.(5) thin planar object
Figure 2:
Exaggerated view of a transverse curvature applied by the blade to the assembly
from the surface when applying an electrical signal to the blade. The surface
thus controlled by the blade serves as an acoustic amplifier to the system.

Figure3
(1) lame vibrante.Figure3
(1) vibrating blade.

(2) surface plane de faible épaisseur, bombée. (2) flat, curved, thin surface.

Figure 4:
(1) lame vibrante
(2) substrat
(A) sens de déformation du substrat
(B) axe de moindre déformation Figure 5:
(1A) Lame fréquences médianes.Figure 4:
(1) vibrating blade
(2) substrate
(A) direction of deformation of the substrate
(B) axis of least deformation Figure 5:
(1A) Mid-frequency blade.

(1B) Lame fréquences basses. (1B) Low frequency blade.

(1C) Lame fréquences hautes. (1C) High frequency blade.

(2) Surface plane de faible épaisseur (0,5 à 1,2 mm).  (2) Thin flat surface (0.5 to 1.2 mm).

Claims (6)

Revendications Claims 1 Montage acoustique destiné aux dispositifs électroniques d'épaisseur inférieure ou égale à 1,2 mm ayant pour but de générer des signaux acoustiques dans la gamme des fréquences compatibles avec leur transport par le réseau téléphonique, caractérisé par le fait qu'il comporte au moins une lame vibrante de type piezzo électrique, ou Pvdf ou de tout autre matériau capable de vibrer sous l'action d'un dispositif électronique. 1 Acoustic assembly intended for electronic devices with a thickness less than or equal to 1.2 mm intended to generate acoustic signals in the range of frequencies compatible with their transport by the telephone network, characterized in that it comprises at least a vibrating blade of the piezoelectric type, or Pvdf or of any other material capable of vibrating under the action of an electronic device. 2.Montage acoustique selon la revendication 1 caractérisé par le fait que la lame vibrante est montée solidairement au substrat.2.Acoustic assembly according to claim 1 characterized in that the vibrating blade is mounted integrally with the substrate. 3.Montage acoustique selon les revendications 1 et 2 caractérisé par la suppression de toute cavité, ou caisse de résonance acoustique dans le dispositif.3. Acoustic assembly according to claims 1 and 2 characterized by the elimination of any cavity, or acoustic resonance box in the device. 4.Montage acoustique selon l'une des revendications 1 à 3 caractérisé par le fait que la lame vibrante est montée suivant l'axe de plus grande longueur du dispositif, de façon a subir un minimum de contraintes mécaniques.4.Acoustic assembly according to one of claims 1 to 3 characterized in that the vibrating blade is mounted along the axis of greatest length of the device, so as to undergo a minimum of mechanical stresses. 5.Montage acoustique suivant l'une des revendications 1 à 4 caractérisé par le fait que la lame vibrante est recouverte par une fine couche de matériau rendant le dispositif totalement étanche aux liquides et substances oxydantes.5.Acoustic assembly according to one of claims 1 to 4 characterized in that the vibrating blade is covered by a thin layer of material making the device completely sealed against liquids and oxidizing substances. 6.Montage acoustique suivant la revendication 1 caractérisé qu'il peut, en tant que variante, comporter plusieurs lames vibrantes dédiées à des gammes de fréquence différentes et dans ce cas, disposées de part et d'autre de l'axe de plus grande longueur, au plus près de cet axe. 6.Acoustic assembly according to claim 1 characterized in that it can, as a variant, include several vibrating blades dedicated to different frequency ranges and in this case, arranged on either side of the axis of greatest length , as close as possible to this axis.
FR9610859A 1996-09-02 1996-09-02 Acoustic signal assembly for credit card sized support for telephone system access Withdrawn FR2752972A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR9610859A FR2752972A1 (en) 1996-09-02 1996-09-02 Acoustic signal assembly for credit card sized support for telephone system access

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Application Number Priority Date Filing Date Title
FR9610859A FR2752972A1 (en) 1996-09-02 1996-09-02 Acoustic signal assembly for credit card sized support for telephone system access

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001039113A1 (en) * 1999-11-22 2001-05-31 Tel+ Systeme Inc. An authentication card incorporating a piezoelectric element

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2615984A1 (en) * 1987-05-30 1988-12-02 Toshiba Kk SMARTCARD
FR2705853A1 (en) * 1993-05-28 1994-12-02 Numerical Systems Communicatio Device for automatically dialling telephone numbers
EP0664633A1 (en) * 1994-01-25 1995-07-26 Gemplus Card International Device for generating acoustic signals and transmitting the same on a telephone line

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2615984A1 (en) * 1987-05-30 1988-12-02 Toshiba Kk SMARTCARD
FR2705853A1 (en) * 1993-05-28 1994-12-02 Numerical Systems Communicatio Device for automatically dialling telephone numbers
EP0664633A1 (en) * 1994-01-25 1995-07-26 Gemplus Card International Device for generating acoustic signals and transmitting the same on a telephone line

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001039113A1 (en) * 1999-11-22 2001-05-31 Tel+ Systeme Inc. An authentication card incorporating a piezoelectric element

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