EP0034730B1 - Transducer disk for piezo-electric transducers - Google Patents

Transducer disk for piezo-electric transducers Download PDF

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Publication number
EP0034730B1
EP0034730B1 EP81100734A EP81100734A EP0034730B1 EP 0034730 B1 EP0034730 B1 EP 0034730B1 EP 81100734 A EP81100734 A EP 81100734A EP 81100734 A EP81100734 A EP 81100734A EP 0034730 B1 EP0034730 B1 EP 0034730B1
Authority
EP
European Patent Office
Prior art keywords
piezo
adhesive
layer
transducer
plate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP81100734A
Other languages
German (de)
French (fr)
Other versions
EP0034730A1 (en
Inventor
Erwin Dipl.-Ing. Martin
Konrad Dr. Walliser
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Priority to AT81100734T priority Critical patent/ATE10694T1/en
Publication of EP0034730A1 publication Critical patent/EP0034730A1/en
Application granted granted Critical
Publication of EP0034730B1 publication Critical patent/EP0034730B1/en
Expired legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only 
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R17/00—Piezoelectric transducers; Electrostrictive transducers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2499/00—Aspects covered by H04R or H04S not otherwise provided for in their subgroups
    • H04R2499/10—General applications
    • H04R2499/11—Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's

Definitions

  • the invention relates to a transducer plate for piezoelectric transducers in telephony with a carrier plate and a piezoceramic, which is connected on one side by adhesives and is provided with electrodes on both sides.
  • the frequency response of the telephone converter must be within a prescribed tolerance scheme.
  • the resonance frequency of the fourth partial oscillation characterized by a node circle, is also placed at the upper edge of the transmission range.
  • Special resonators then have the task of dampening the resonance peaks to a predetermined level. It is known to dampen the basic resonance by means of absorption resonators arranged in the transducer.
  • the piezoceramic layer of the transducer plate is connected to the transducer plate by an adhesive.
  • the adhesive layer is designed as an extremely thin layer (US-A-4 047 060), so that the adhesive hardens quickly and has no disruptive influence on the frequency response of the transducer. It has been found that such an adhesive layer brought with it problems with regard to strength and problems with regard to usability in machines.
  • the adhesive is applied on one side over the entire surface of the carrier plate, and the piezoceramic is applied thereon, the layer formed by the adhesive having such a thickness that it increases the resonance peaks, in particular that of the fourth Partial vibration, dampened.
  • the adhesive layer is therefore more strongly developed. It is now possible to use adhesives which can be used much more easily than adhesives which are intended to achieve a practically negligible thin layer.
  • the spectrum of available adhesives has been expanded considerably, so that, among other things, the adhesive strength between the piezoceramic and the carrier plate has been increased considerably, even under extreme environmental conditions.
  • To dampen the fourth partial vibration such an embodiment of the adhesive layer forms an extremely expedient solution, since further means which dampen this vibration can be largely dispensed with if the thickness of the adhesive layer is adjusted precisely to this.
  • the converter plate shown in FIGS. 1 and 2 consists of a carrier plate 1 made of an aluminum alloy.
  • An adhesive layer 2 which consists of a copolymer or the like, is applied to the entire surface of one side of the carrier plate.
  • This layer is followed by the piezoceramic 3, which is coated on both sides with an electrically conductive layer 4, 5 forming the piezoceramic.
  • the contact is made via wires or ribbons, the ribbon 6 being shown in FIG. 2, which is held clamped between the piezoceramic 3 and the adhesive layer 2.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Piezo-Electric Transducers For Audible Bands (AREA)
  • Transducers For Ultrasonic Waves (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Electrophonic Musical Instruments (AREA)

Abstract

A transducer plate for piezo-electrical transducers has a piezo-electrical layer or member applied thereon. Unwanted oscillations, in particular the fourth partial oscillation, are attenuated by providing a thickness of the adhesive layer chosen for attenuation properties, and which is thicker than prior art adhesive layers.

Description

Die Erfindung betrifft eine Wandlerplatte für piezoelektrische Wandler der Fernsprechtechnik mit einer Trägerplatte und einer durch Klebemittel verbundenen einseitig darauf aufgebrachten beidseitig mit Elektroden versehenen Piezokeramik.The invention relates to a transducer plate for piezoelectric transducers in telephony with a carrier plate and a piezoceramic, which is connected on one side by adhesives and is provided with electrodes on both sides.

Innerhalb des Fernsprechübertragungsbereichs von ca. 200 bis 4000 Hz muss der Frequenzgang des Fernsprechwandlers in einem vorgeschriebenen Toleranzschema liegen. Um dieser Bedingung zu genügen, ist es bekannt, die Grundresonanz der Biegeschwingung innerhalb des Fernsprechübertragungsbereiches zu legen, wodurch die Empfindlichkeit des Wandlers auf das notwendige Mass erhöht wird. Zur Verbreiterung des Übertragungsbereiches sowie zur Anhebung der Empfindlichkeit legt man weiterhin die Resonanzfrequenz der durch einen Knotenkreis gekennzeichneten vierten Teilschwingung an den oberen Rand des Übertraungsbereiches. Spezielle Resonatoren haben dann die Aufgabe, die Resonanzüberhöhungen auf ein vorgegebenes Mass abzudämpfen. So ist es bekannt, die Grundresonanz durch im Wandler angeordnete Absorptionsresonatoren zu dämpfen. Zur Dämpfung der vierten Teilschwingung eignen sich diese Resonatoren jedoch nicht, da die dazu erforderlichen kleinen Durchbrüche z. B. im Wandlerboden nur schwer herstellbar bzw. dann leicht verschmutzen können, so dass ein Betrieb mit gleichbleibendem Frequenzgang nicht gewährleistet werden kann. Aus diesem Grund hat man die Wandlerplatte in speziellen Lagerkörpern (DE-PS 1 961 217) gelagert. Weiterhin hat man die piezokeramische Schicht so bemessen, dass der Knotenkreis der vierten Teilschwingung sich innerhalb der Piezoschicht ausbildet.Within the telephone transmission range of approx. 200 to 4000 Hz, the frequency response of the telephone converter must be within a prescribed tolerance scheme. In order to meet this condition, it is known to place the fundamental resonance of the bending vibration within the telephone transmission range, whereby the sensitivity of the transducer is increased to the necessary extent. In order to broaden the transmission range and to increase the sensitivity, the resonance frequency of the fourth partial oscillation, characterized by a node circle, is also placed at the upper edge of the transmission range. Special resonators then have the task of dampening the resonance peaks to a predetermined level. It is known to dampen the basic resonance by means of absorption resonators arranged in the transducer. However, these resonators are not suitable for damping the fourth partial oscillation, since the small openings required for this. B. in the converter floor is difficult to manufacture or can easily become dirty, so that operation with a constant frequency response cannot be guaranteed. For this reason, the converter plate has been stored in special bearing bodies (DE-PS 1 961 217). Furthermore, the piezoceramic layer has been dimensioned such that the node circle of the fourth partial oscillation is formed within the piezo layer.

Wie eingangs bereits erwähnt, ist die piezokeramische Schicht der Wandlerplatte mit der Wandlerplatte durch eine Klebung miteinander verbunden. Die Klebeschicht ist als äusserst dünne Schicht ausgebildet (US-A-4 047 060), so dass der Kleber schnell aushärtet und keinen störenden Einfluss auf den Frequenzgang des Wandlers nahm. Es hat sich herausgestellt, dass eine derartige Klebeschicht Probleme hinsichtlich der Festigkeit sowie Probleme hinsichtlich der Einsetzbarkeit in Automaten mit sich brachte.As already mentioned at the beginning, the piezoceramic layer of the transducer plate is connected to the transducer plate by an adhesive. The adhesive layer is designed as an extremely thin layer (US-A-4 047 060), so that the adhesive hardens quickly and has no disruptive influence on the frequency response of the transducer. It has been found that such an adhesive layer brought with it problems with regard to strength and problems with regard to usability in machines.

Es ist Aufgabe der Erfindung, eine weitere Möglichkeit zur Dämpfung insbesondere der vierten Teilschwingung aufzuzeigen, durch die gleichzeitig die Nachteile der bisher verwendeten Klebeschicht vermieden werden.It is an object of the invention to show a further possibility for damping, in particular the fourth partial vibration, by means of which the disadvantages of the adhesive layer previously used are avoided.

Diese Aufgabe wird gemäss der Erfindung dadurch gelöst, dass das Klebemittel einseitig über der gesamten Oberfläche der Trägerplatte aufgebracht ist, dass darauf die Piezokeramik aufgebracht ist, wobei die durch das Klebemittel gebildete Schicht eine derartige Stärke aufweist, dass sie die Resonanzüberhöhungen, insbesondere die der vierten Teilschwingung, dämpfend beeinflusst.This object is achieved according to the invention in that the adhesive is applied on one side over the entire surface of the carrier plate, and the piezoceramic is applied thereon, the layer formed by the adhesive having such a thickness that it increases the resonance peaks, in particular that of the fourth Partial vibration, dampened.

Die Klebeschicht wird demnach im Gegensatz zu der bisherigen Ausbildung stärker ausgebildet. Damit können nunmehr Klebemittel Verwendung finden, die wesentlich unproblematischer einsetzbar sind als Klebemittel, durch die eine praktisch vernachlässigbar dünne Schicht erzielt werden soll. Das Spektrum der verfügbaren Klebemittel ist damit um ein Erhebliches erweitert worden, so dass unter anderem die Haftfestigkeit zwischen Piezokeramik und Trägerplatte selbst unter extremen Umweltbedingungen erheblich vergrössert werden konnte. Zur Dämpfung der vierten Teilschwingung bildet eine derartige Ausbildung der Klebeschicht eine äusserst zweckmässige Lösung, da auf weitere diese Schwingung dämpfende Mittel weitgehend verzichtet werden kann, wenn man die Stärke der Klebeschicht exakt daraufhin abstimmt.In contrast to the previous training, the adhesive layer is therefore more strongly developed. It is now possible to use adhesives which can be used much more easily than adhesives which are intended to achieve a practically negligible thin layer. The spectrum of available adhesives has been expanded considerably, so that, among other things, the adhesive strength between the piezoceramic and the carrier plate has been increased considerably, even under extreme environmental conditions. To dampen the fourth partial vibration, such an embodiment of the adhesive layer forms an extremely expedient solution, since further means which dampen this vibration can be largely dispensed with if the thickness of the adhesive layer is adjusted precisely to this.

Durch die EP-A 0 007 036 ist es zwar bekannt, durch Überziehen der Wandlerplatte mit einer Kunststoffschicht das Frequenzverhalten der Wandlerplatte zu beeinflussen. Ähnliches ist durch die US-A 3 846 650 bekannt. Die hier erwähnte Schicht dient jedoch keinesfalls als Klebemittel für die Piezokeramik, so dass ein zusätzlicher Aufwand bei der Herstellung derartiger Wandlerplatten erforderlich ist.From EP-A 0 007 036 it is known to influence the frequency response of the converter plate by covering the converter plate with a plastic layer. The like is known from US-A 3 846 650. However, the layer mentioned here in no way serves as an adhesive for the piezoceramic, so that additional effort is required in the production of such converter plates.

Weiterhin ist es durch die US-A 4 047 060 bekannt, eine Zwischenschicht zwischen Piezokeramik und Träger anzuordnen. Hier geht es jedoch um gewisse Festigkeitsprobleme, wobei gezeigt wird, wie sich die Scherung mit der Frequenz ändert. Das Frequenzverhalten mit dieser Schicht zu beeinflussen, ist nicht Aufgabe dieser Anordnung.Furthermore, it is known from US Pat. No. 4,047,060 to arrange an intermediate layer between the piezoceramic and the carrier. However, this involves certain strength problems, showing how shear changes with frequency. It is not the task of this arrangement to influence the frequency behavior with this layer.

Im folgenden sei die Erfindung anhand von zwei Figuren erläutert.The invention is explained below with reference to two figures.

Es zeigen:

  • Fig. 1 eine Wandlerplatte im Schnitt und
  • Fig. 2 die Wandlerplatte nach Fig. 1 in Draufsicht.
Show it:
  • Fig. 1 is a converter plate in section and
  • Fig. 2, the converter plate of FIG. 1 in plan view.

Die in Figur 1 und 2 gezeigte Wandlerplatte besteht aus einer Trägerplatte 1 aus einer Aluminium-Legierung. Auf einer Seite der Trägerplatte ist ganzflächig eine Klebeschicht 2 aufgebracht, die aus einem Copolymer oder dergleichen besteht. An diese Schicht schliesst sich die Piezokeramik 3 an, die beidseitig mit je einer die Piezokeramik überdeckende elektrisch leitfähigen, Elektroden 4, 5 bildenden Schicht überzogen ist. Die Kontaktierung erfolgt über Drähtchen oder Bändchen, wobei in Fig. 2 das Bändchen 6 dargestellt ist, das zwischen Piezokeramik 3 und Klebeschicht 2 geklemmt gehalten ist.The converter plate shown in FIGS. 1 and 2 consists of a carrier plate 1 made of an aluminum alloy. An adhesive layer 2, which consists of a copolymer or the like, is applied to the entire surface of one side of the carrier plate. This layer is followed by the piezoceramic 3, which is coated on both sides with an electrically conductive layer 4, 5 forming the piezoceramic. The contact is made via wires or ribbons, the ribbon 6 being shown in FIG. 2, which is held clamped between the piezoceramic 3 and the adhesive layer 2.

Claims (1)

  1. A transducer plate for piezo-electric transducers in telephone technology, having a carrier plate (1) and a piezo-ceramic (3) located at one side thereof and connected thereto by adhesive, and is provided on both sides with electrodes (4, 5), characterised in that the adhesive (2) is applied to one side over the entire surface of the carrier plate (1), that the piezo-ceramic (3) is applied thereon, the layer formed by the adhesive (2) having a thickness such that it influences the resonance peaks, in particular those of the fourth harmonic, in a damping manner.
EP81100734A 1980-02-15 1981-02-02 Transducer disk for piezo-electric transducers Expired EP0034730B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81100734T ATE10694T1 (en) 1980-02-15 1981-02-02 TRANSDUCER PLATE FOR PIEZOELECTRICAL TRANSDUCERS.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3005708A DE3005708C2 (en) 1980-02-15 1980-02-15 Transducer plate for piezoelectric transducers
DE3005708 1980-02-15

Publications (2)

Publication Number Publication Date
EP0034730A1 EP0034730A1 (en) 1981-09-02
EP0034730B1 true EP0034730B1 (en) 1984-12-05

Family

ID=6094723

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81100734A Expired EP0034730B1 (en) 1980-02-15 1981-02-02 Transducer disk for piezo-electric transducers

Country Status (9)

Country Link
US (1) US4368401A (en)
EP (1) EP0034730B1 (en)
JP (1) JPS60839B2 (en)
AT (1) ATE10694T1 (en)
AU (1) AU548536B2 (en)
BR (1) BR8100889A (en)
DE (1) DE3005708C2 (en)
FI (1) FI810453L (en)
ZA (1) ZA81972B (en)

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JPS57113697A (en) * 1981-01-05 1982-07-15 Murata Mfg Co Ltd Piezoelectric type speaker
DE3232177A1 (en) * 1982-08-30 1984-03-01 Siemens AG, 1000 Berlin und 8000 München PIEZOELECTRIC CONVERTER
US4805157A (en) * 1983-12-02 1989-02-14 Raytheon Company Multi-layered polymer hydrophone array
DE3518819A1 (en) * 1985-05-24 1986-11-27 Siemens AG, 1000 Berlin und 8000 München Electro-acoustic transducer
EP0209053A3 (en) * 1985-07-18 1987-09-02 Wolfgang Prof. Dr. Eisenmenger Method and apparatus for the non-contacting disintegration of concretions in a living body
DE3702378A1 (en) * 1987-01-27 1988-08-04 Siemens Ag PIEZOELECTRIC CONVERTER FOR HEALTHY HEARTS
DE3736896A1 (en) * 1987-10-30 1989-05-11 Siemens Ag Electroacoustic transducer
DE8805953U1 (en) * 1988-05-05 1988-07-07 Höntzsch GmbH, 71334 Waiblingen Electroacoustic transducer
JPH05111097A (en) * 1991-10-15 1993-04-30 Murata Mfg Co Ltd Piezoelectric sound generating body
GB2272056A (en) * 1992-11-03 1994-05-04 Marconi Gec Ltd Solid-state resonator device
US5828768A (en) * 1994-05-11 1998-10-27 Noise Cancellation Technologies, Inc. Multimedia personal computer with active noise reduction and piezo speakers
US5638456A (en) * 1994-07-06 1997-06-10 Noise Cancellation Technologies, Inc. Piezo speaker and installation method for laptop personal computer and other multimedia applications
KR19990044067A (en) 1995-09-02 1999-06-25 에이지마. 헨리 Bending machine
US5901231A (en) 1995-09-25 1999-05-04 Noise Cancellation Technologies, Inc. Piezo speaker for improved passenger cabin audio systems
US5873154A (en) * 1996-10-17 1999-02-23 Nokia Mobile Phones Limited Method for fabricating a resonator having an acoustic mirror
US6181797B1 (en) 1999-01-09 2001-01-30 Noise Cancellation Technologies, Inc. Piezo speaker for improved passenger cabin audio systems
US6603241B1 (en) * 2000-05-23 2003-08-05 Agere Systems, Inc. Acoustic mirror materials for acoustic devices
JP2004015767A (en) * 2002-06-12 2004-01-15 Murata Mfg Co Ltd Piezoelectric sounding body and piezoelectric electroacoustic transducer using piezoelectric sounding body
US20060013417A1 (en) * 2004-07-16 2006-01-19 Intier Automotive Inc. Acoustical panel assembly

Citations (6)

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Publication number Priority date Publication date Assignee Title
DE1948932A1 (en) * 1968-09-30 1970-04-09 Philips Nv Converter for converting acoustic vibrations into electrical vibrations and vice versa in the form of a vibrating plate with at least one layer of piezoelectric material
US3728562A (en) * 1971-10-18 1973-04-17 Bell Telephone Labor Inc Electroacoustic transducer having transducing element supporting means
FR2179883A1 (en) * 1972-04-10 1973-11-23 Motorola Inc
US3846650A (en) * 1970-10-08 1974-11-05 Dynamics Corp Massa Div Electroacoustic transducer of the vibratile diaphragm type with controlled uniformity of performance characteristics and method for controlling uniformity
US4047060A (en) * 1971-09-07 1977-09-06 Motorola, Inc. Acoustic transducer with elastomeric coupling
EP0007036A1 (en) * 1978-07-17 1980-01-23 Siemens Aktiengesellschaft Electroacoustic transducer

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BE759888A (en) * 1969-12-05 1971-06-04 Siemens Ag ELECTRO-ACOUSTIC TRANSDUCER, ESPECIALLY MICROPHONE FOR TELEPHONE SYSTEMS
US3708702A (en) * 1970-12-02 1973-01-02 Siemens Ag Electroacoustic transducer
US3733590A (en) * 1971-04-15 1973-05-15 A Kaufman Optimum electrode configuration ceramic memories with ceramic motor element and mechanical damping
US3863250A (en) * 1973-01-30 1975-01-28 Jr Arthur Mccluskey Glass breakage detector
US4310730A (en) * 1979-07-25 1982-01-12 Aaroe Kenneth T Shielded piezoelectric acoustic pickup for mounting on musical instrument sounding boards

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1948932A1 (en) * 1968-09-30 1970-04-09 Philips Nv Converter for converting acoustic vibrations into electrical vibrations and vice versa in the form of a vibrating plate with at least one layer of piezoelectric material
US3846650A (en) * 1970-10-08 1974-11-05 Dynamics Corp Massa Div Electroacoustic transducer of the vibratile diaphragm type with controlled uniformity of performance characteristics and method for controlling uniformity
US4047060A (en) * 1971-09-07 1977-09-06 Motorola, Inc. Acoustic transducer with elastomeric coupling
US3728562A (en) * 1971-10-18 1973-04-17 Bell Telephone Labor Inc Electroacoustic transducer having transducing element supporting means
FR2179883A1 (en) * 1972-04-10 1973-11-23 Motorola Inc
EP0007036A1 (en) * 1978-07-17 1980-01-23 Siemens Aktiengesellschaft Electroacoustic transducer

Also Published As

Publication number Publication date
FI810453L (en) 1981-08-16
ZA81972B (en) 1982-03-31
JPS56131300A (en) 1981-10-14
AU6727181A (en) 1981-08-20
US4368401A (en) 1983-01-11
EP0034730A1 (en) 1981-09-02
BR8100889A (en) 1981-08-25
DE3005708C2 (en) 1984-08-30
DE3005708A1 (en) 1981-08-20
JPS60839B2 (en) 1985-01-10
ATE10694T1 (en) 1984-12-15
AU548536B2 (en) 1985-12-19

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