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EP0035222A1 - Electro-acoustic transducer - Google Patents

Electro-acoustic transducer Download PDF

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Publication number
EP0035222A1
EP0035222A1 EP81101327A EP81101327A EP0035222A1 EP 0035222 A1 EP0035222 A1 EP 0035222A1 EP 81101327 A EP81101327 A EP 81101327A EP 81101327 A EP81101327 A EP 81101327A EP 0035222 A1 EP0035222 A1 EP 0035222A1
Authority
EP
European Patent Office
Prior art keywords
partition plate
passage openings
sound passage
plate
socket
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.)
Ceased
Application number
EP81101327A
Other languages
German (de)
French (fr)
Inventor
Erwin Dipl.-Ing. Martin
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
Siemens Corp
Original Assignee
Siemens AG
Siemens Corp
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, Siemens Corp filed Critical Siemens AG
Publication of EP0035222A1 publication Critical patent/EP0035222A1/en
Ceased 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
    • 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
    • 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
    • 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 an electroacoustic transducer with a transducer plate arranged in a housing, through which the volume in the housing is divided into a vestibule and a rear space, further with a facade that closes the vestibule and is provided with sound passage openings, wherein means for damping the Resonance peaks are provided, furthermore with a partition plate arranged in the anteroom between the plate and socket, the socket and partition plate being provided with sound passage openings and the sound passage openings of the socket being arranged offset with respect to the sound passage openings of the partition plate, furthermore with means having damping properties in the region of the partition plate, which means that Cover the sound passage openings of the partition plate.
  • the means arranged in the antechamber of the transducer plate serve primarily to reduce the resonance peaks of the harmonics, in particular the resonance peaks of the fourth partial vibration, which is characterized by a node circle.
  • the specified means form an acoustic low-pass filter, the mass and damping effect of which is reinforced by the porous damping disc between the frame and the separating plate.
  • the sound passage openings of the separating plate are formed by a plurality of narrow slits with respect to the sound passage openings of the sockets.
  • An expedient embodiment is that the narrow slots are combined into groups and that an enlarged opening in the partition plate is connected to each such group.
  • the lengths of the slots can be varied independently of the thickness of the partition plate.
  • a particularly expedient version is obtained if the enlarged opening faces the volume between the socket and the partition plate, while the narrow slots face the volume between the transducer plate and the partition plate.
  • the illustration shows an electroacoustic transducer in section.
  • the carrier 2 which carries a circuit board 3 with electronic components on its side facing the bottom of the housing 1.
  • Two contact blades are arranged on this circuit board, which protrude through recesses 5 of the housing, form the electrical connection to the outside and fixes the carrier 2 with circuit board 3 in the housing.
  • the carrier 2 is provided with two absorption resonators, of which the absorption resonator 6 covered with a silk disk 7 is shown.
  • a bearing body 8 is also arranged on the carrier 2, over which a transducer plate 10 provided with a piezoceramic layer 9 is supported. Another bearing body 11 forms the counter bearing.
  • the housing 1 is closed off by a separating plate 12 which is inseparably connected to the housing.
  • This partition plate has a plurality of sound passage openings 13 arranged in a circle, each of which is followed by a group of narrow slots 19, 20. The arrangement of the slots is chosen so that they face the volume immediately in front of the transducer plate.
  • the separating plate is provided on the side facing the converter plate with radially outwardly extending ribs 14.
  • the transducer thus formed is closed by a socket 15, which in turn has sound passage openings 16 arranged in a circle. These sound passage openings are arranged in a circle with a larger diameter than the sound passage openings arranged in the partition plate.
  • a damping disc 17 which is mounted in a cylindrical extension 18 of the socket and partially fills the space in front of the partition plate. The damping disc is dimensioned so that it covers the sound passage openings of the partition plate.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Piezo-Electric Transducers For Audible Bands (AREA)

Abstract

Elektroakustischer Wandler mit einer mit einer piezoelektrischen Schicht (9) versehenen Wandlerplatte (10), die das Gehäuse (1) des Wandlers in einen Vor- und Rückraum aufteilt. Im Vorraum sind Mittel zur Dämpfung von Resonanzüberhöhungen vorgesehen, die aus Helmholtzresonatoren und einem darüber angeordneten Dämpfungsscheibchen bestehen. Aufgabe ist es, die Helmholtzresonatoren so auszugestalten, daß deren wirksame Fläche durch das Dämpfungsscheibchen nicht verkleinert wird. Dies wird gemäß der Erfindung dadurch erreicht, daß die wirksame Fläche u.a. durch Schlitze (14) in einer Trennplatte (12) gebildet wird.Electroacoustic transducer with a transducer plate (10) provided with a piezoelectric layer (9), which divides the housing (1) of the transducer into a front and rear space. Means for damping resonance peaks are provided in the anteroom, which consist of Helmholtz resonators and a damping disc arranged above them. The task is to design the Helmholtz resonators so that their effective area is not reduced by the damping disk. This is achieved according to the invention in that the effective area i.a. is formed by slots (14) in a partition plate (12).

Description

Die Erfindung betrifft einen elektroakustischen Wandler mit einer in einem Gehäuse angeordneten Wandlerplatte, durch die das Volumen in dem Gehäuse in einen Vorraum und einen Rückraum aufgeteilt ist, weiterhin mit einer, den Vorraum verschließenden, mit Schalldurchlaßöffnungen versehenen Fassing, wobei im Vorraum Mittel zur Dämpfung der Resonanzüberhöhungen vorgesehen sind, weiterhin mit einer im Vorraum zwischen Platte und Fassung angeordneten Trennplatte, wobei Fassung und Trennplatte mit SchalldurchlaBöffnungen versehen und die SchalldurchlaBöffnungen der Fassung gegenüber den SchalldurchlaBöffnungen der Trennplatte versetzt angeordnet sind, weiterhin mit im Bereich der Trennplatte dämpfende Eigenschaften aufweisenden Mitteln, die die Schalldurchlaßöffnungen der Trennplatte überdecken.The invention relates to an electroacoustic transducer with a transducer plate arranged in a housing, through which the volume in the housing is divided into a vestibule and a rear space, further with a facade that closes the vestibule and is provided with sound passage openings, wherein means for damping the Resonance peaks are provided, furthermore with a partition plate arranged in the anteroom between the plate and socket, the socket and partition plate being provided with sound passage openings and the sound passage openings of the socket being arranged offset with respect to the sound passage openings of the partition plate, furthermore with means having damping properties in the region of the partition plate, which means that Cover the sound passage openings of the partition plate.

Ein derartig aufgebauter Wandler ist bekannt. Die im Vorraum der Wandlerplatte angeordneten Mittel dienen vor allem dazu, die Resonanzüberhöhungen der Oberschwingungen, insbesondere die Resonanzüberhöhung der durch einen Knotenkreis gekennzeichneten vierten Teilschwingung, abzubauen. Insofern bilden die angegebenen Mittel einen akustischen Tiefpaß, dessen Massen-und Dämpfungswirkung durch die poröse Dämpfungsscheibe zwischen Fassung und Trennplatte verstärkt wird.Such a converter is known. The means arranged in the antechamber of the transducer plate serve primarily to reduce the resonance peaks of the harmonics, in particular the resonance peaks of the fourth partial vibration, which is characterized by a node circle. In this respect, the specified means form an acoustic low-pass filter, the mass and damping effect of which is reinforced by the porous damping disc between the frame and the separating plate.

Es ist Aufgabe der Erfindung, den akustischen Tiefpaß derart zu verbessern, daß er von eventuell vorhandenen Streuungen der Dämpfungsscheibe unabhängig wird, um nachteilige Auswirkungen auf die Frequenzgangs- und Bezugsdämpfungst.oleranz zu vermeiden.It is an object of the invention to improve the acoustic low-pass filter in such a way that it becomes independent of any scattering of the damping disk, in order to avoid adverse effects on the frequency response and reference damping tolerance.

Die Aufgabe wird gemäß der Erfindung dadurch gelöst, daß die Schalldurchlaßöffnungen der Trennplatte durch eine Vielzahl von in Bezug auf die Schalldurchlaßöffnungen der Fassungen schmalen Schlitzen gebildet sind.The object is achieved according to the invention in that the sound passage openings of the separating plate are formed by a plurality of narrow slits with respect to the sound passage openings of the sockets.

Durch diese Maßnahmen werden die Schalldurchlaßöffnungen in der Trennplatte durch schmale Schlitze ersetzt. Damit überwiegt die Dämpfung in den Schlitzen der Trennplatte, wenn die Dämpfungsscheibe aus relativ durchlässigem Schaumstoff besteht. Damit gehen auch Materialstreuungen der Dämpfungsscheibe nur unwesentlich in das Frequenzverhalten des akustischen Tiefpasses ein.These measures replace the sound passage openings in the partition plate with narrow slots. The damping in the slots of the separating plate therefore predominates if the damping disc consists of relatively permeable foam. This means that material scatter from the damping disc is only negligible in the frequency response of the acoustic low-pass filter.

Eine zweckmäßige Ausführung besteht darin, daß die schmalen Schlitze zu Gruppen zusammengefaßt sind und daß sich jeweils an eine derartige Gruppe eine erweiterte Öffnung in der Trennplatte anschließt.An expedient embodiment is that the narrow slots are combined into groups and that an enlarged opening in the partition plate is connected to each such group.

Durch eine derartige Maßnahme sind die Längen der Schlitze unabhängig von der Stärke der Trennplatte variierbar.With such a measure, the lengths of the slots can be varied independently of the thickness of the partition plate.

Eine besonders zweckmäßige Ausführung erhält man, wenn die erweiterte Öffnung dem zwischen Fassung und Trennplatte befindlichen Volumen zugewandt ist, während die schmalen Schlitze dem zwischen Wandlerplatte und Trennplatte befindlichen Volumen zugewandt sind.A particularly expedient version is obtained if the enlarged opening faces the volume between the socket and the partition plate, while the narrow slots face the volume between the transducer plate and the partition plate.

Damit wird ein freier Zugang der Luft völlig unabhängig von der Dämpfungsscheibe zu den Schlitzen gewährleistet.This ensures free air access to the slots, regardless of the damping disc.

Im folgenden sei die Erfindung anhand einer Abbildung näher erläutert.The invention is explained in more detail below with the aid of an illustration.

Die Abbildung zeigt einen elektroakustischen Wandler im Schnitt.The illustration shows an electroacoustic transducer in section.

In einem Gehäuse 1 sind nacheinander folgende Teile untergebracht. Zunächst ist der Träger 2 zu nennen, der auf seiner dem Boden des Gehäuses 1 zugewandten Seite eine Schaltungsplatte 3 mit elektronischen Bauelementen trägt. An dieser Schaltungsplatte sind zwei Kontaktmesser angeordnet (Kontaktmesser 4 dargestellt), die durch Ausnehmungen 5 des Gehäuses hindurchragen, den elektrischen Anschluß nach außen-bilden und den Träger 2 mit Schaltungsplatte 3 im Gehäuse festlegt. Der Träger 2 ist mit zwei Absorptionsresonatoren versehen, von denen der mit einer Seidenscheibe 7 abgedeckte Absorptionsresonator 6 dargestellt ist.The following parts are housed one after the other in a housing 1. First, the carrier 2 is to be mentioned, which carries a circuit board 3 with electronic components on its side facing the bottom of the housing 1. Two contact blades (contact blades 4 shown) are arranged on this circuit board, which protrude through recesses 5 of the housing, form the electrical connection to the outside and fixes the carrier 2 with circuit board 3 in the housing. The carrier 2 is provided with two absorption resonators, of which the absorption resonator 6 covered with a silk disk 7 is shown.

Auf dem Träger 2 ist weiterhin ein Lagerkörper 8 angeordnet, über dem eine mit einer piezokeramischen Schicht 9 versehene Wandlerplatte 10 lagert. Ein weiterer Lagerkörper 11 bildet das Gegenlager. Abgeschlossen ist das Gehäuse 1 durch eine Trennplatte 12, die untrennbar mit dem Gehäuse verbunden ist. Diese Trennplatte weist mehrere in einem Kreis angeordnete Schalldurchlaßöffnungen 13 auf, an die sich jeweils eine Gruppe von schmalen Schlitzen 19, 20 anschließen. Dabei ist die Anordnung der Schlitze so gewählt, daß sie dem unmittelbar vor der Wandlerplatte befindlichen Volumen zugewandt sind. Die Trennplatte ist auf der der Wandlerplatte zugekehrten Seite mit radial nach außen verlaufenden Rippen 14 versehen.A bearing body 8 is also arranged on the carrier 2, over which a transducer plate 10 provided with a piezoceramic layer 9 is supported. Another bearing body 11 forms the counter bearing. The housing 1 is closed off by a separating plate 12 which is inseparably connected to the housing. This partition plate has a plurality of sound passage openings 13 arranged in a circle, each of which is followed by a group of narrow slots 19, 20. The arrangement of the slots is chosen so that they face the volume immediately in front of the transducer plate. The separating plate is provided on the side facing the converter plate with radially outwardly extending ribs 14.

Der so gebildete Wandler ist durch eine Fassung 15 verschlossen, die wiederum in einem Kreis angeordnete Schalldurchlaßöffnungen 16 aufweist. Diese Schalldurchlaßöffnungen sind in einem Kreis mit größerem Durchmesser als die in der Trennplatte angeordneten Schalldurchlaßöffnungen angeordnet. Zwischen Trennplatte und Fassung ist eine Dämpfungsscheibe 17 angeordnet, die in einem zylindrischen Ansatz 18 der Fassung lagert und den Raum vor der Trennplatte teilweise ausfüllt. Dabei ist die Dämpfungsscheibe so bemessen, daß sie die Schalldurchlaßöffnungen der Trennplatte überdeckt.The transducer thus formed is closed by a socket 15, which in turn has sound passage openings 16 arranged in a circle. These sound passage openings are arranged in a circle with a larger diameter than the sound passage openings arranged in the partition plate. Between partition plate and Socket is a damping disc 17 which is mounted in a cylindrical extension 18 of the socket and partially fills the space in front of the partition plate. The damping disc is dimensioned so that it covers the sound passage openings of the partition plate.

Claims (3)

1. Elektroakustischer Wandler mit einer in einem Gehäuse angeordneten Wandlerplatte, durch die das Volumen in dem Gehäuse in einen Vorraum und einen Rückraum aufgeteilt ist, weiterhin mit einer, den Vorraum verschließenden, mit Schalldurchlaßöffnungen versehenen Fassung, wobei im Vorraum Mittel zur Dämpfung der Resonanzüberhöhungen vorgesehen sind, weiterhin mit einer im Vorraum zwischen Platte und Fassung angeordneten Trennplatte, wobei Fassung und Trennplatte mit Schalldurchlaßöffnungen versehen und die Schalldurchlaßöffnungen der Fassung gegenüber den Schalldurchlaßöffnungen der Trennplatte versetzt angeordnet sind, weiterhin mit im Bereich der Trennplatte dämpfende Eigens haften aufweisenden Mitteln, die die Schalldurchlaßöffnungen der Trennplatte überdecken, dadurch gekennzeichnet , daß die Schalldurchlaßöffnungen der Trennplatte (12) durch eine Vielzahl von in Bezug auf die Schalldurchlaßöffnungen der Fassungen schmalen Schlitzen (19, 20) gebildet sind..1. Electroacoustic transducer with a transducer plate arranged in a housing, through which the volume in the housing is divided into an anteroom and a rear space, also with a socket that closes the anteroom and is provided with sound passage openings, wherein means for damping the resonance peaks are provided in the anteroom are, furthermore with a partition plate arranged in the antechamber between the plate and the socket, the socket and partition plate being provided with sound passage openings and the sound passage openings of the socket being staggered with respect to the sound passage openings of the partition plate, and furthermore having agents which dampen the sound passage openings in the region of the partition plate and are liable of the partition plate, characterized in that the sound passage openings of the partition plate (12) are formed by a plurality of narrow slots (19, 20) with respect to the sound passage openings of the sockets. 2..Elektroakustischer Wandler nach Anspruch 1, dadurch gekennzeichnet , daß die schmalen Schlitze (19, 20) zu Gruppen zusammengefaßt sind und daß sich jeweils an eine derartige Gruppe eine erweiterte Öffnung in der Trennplatte (12) anschließt.2..Electroacoustic transducer according to claim 1, characterized in that the narrow slots (19, 20) are combined into groups and that each such group is followed by an enlarged opening in the partition plate (12). 3. Elektroakustischer Wandler nach Anspruch 1, dadurch gekennzeichnet , daß die erweiterte Öffnung dem zwischen Fassung (15) und Trennplatte (13) befindlichen Volumen zugewandt ist, während die schmalen Schlitze (19, 20) dem zwischen Wandlerplatte (10) und Trennplatte (13) befindlichen Volumen zugewandt sind.3. Electroacoustic transducer according to claim 1, characterized in that the enlarged opening facing the volume between the socket (15) and partition plate (13), while the narrow slots (19, 20) between the transducer plate (10) and partition plate (13th ) facing volume.
EP81101327A 1980-02-29 1981-02-24 Electro-acoustic transducer Ceased EP0035222A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19803007808 DE3007808A1 (en) 1980-02-29 1980-02-29 ELECTROACOUSTIC CONVERTER
DE3007808 1980-02-29

Publications (1)

Publication Number Publication Date
EP0035222A1 true EP0035222A1 (en) 1981-09-09

Family

ID=6095959

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81101327A Ceased EP0035222A1 (en) 1980-02-29 1981-02-24 Electro-acoustic transducer

Country Status (8)

Country Link
US (1) US4376232A (en)
EP (1) EP0035222A1 (en)
JP (1) JPS56134898A (en)
AU (1) AU6790581A (en)
BR (1) BR8101221A (en)
DE (1) DE3007808A1 (en)
FI (1) FI810624A7 (en)
ZA (1) ZA811320B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0074424A1 (en) * 1981-09-14 1983-03-23 Heinrich Andreas Peiker Electroacoustic, in particular electrodynamic, transducer protected from moisture and dirt and in particular from iron particles

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3232177A1 (en) * 1982-08-30 1984-03-01 Siemens AG, 1000 Berlin und 8000 München PIEZOELECTRIC CONVERTER
FR2542552B1 (en) * 1983-03-07 1986-04-11 Thomson Csf ELECTROACOUSTIC TRANSDUCER WITH PIEZOELECTRIC DIAPHRAGM
DE3425176A1 (en) * 1984-07-09 1986-02-20 Fernsprech Und Signalbau Kg Sc Piezoelectric telephone capsule
DE3425173A1 (en) * 1984-07-09 1986-01-16 Fernsprech- und Signalbaugesellschaft mbH Schüler & Vershoven, 4300 Essen Piezoelectric telephone capsule
US4646873A (en) * 1986-03-04 1987-03-03 Electro-Voice, Inc. Microphone and acoustic equalizer therefor
DE3630951A1 (en) * 1986-09-11 1988-03-17 Siemens Ag ARRANGEMENT FOR IMPROVING THE FREQUENCY RANGE FOR ELECTROACOUSTIC CONVERTERS
JPH01156696U (en) * 1988-04-18 1989-10-27
US5406161A (en) * 1994-05-24 1995-04-11 Industrial Technology Research Institute Piezoelectric composite receiver
AT400910B (en) * 1994-06-16 1996-04-25 Akg Akustische Kino Geraete ACOUSTIC RESISTANCE, ESPECIALLY FOR ELECTROACOUSTIC TRANSDUCERS

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1160009B (en) * 1960-02-12 1963-12-27 Int Standard Electric Corp Electro-acoustic converter

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2831411C2 (en) * 1978-07-17 1983-10-06 Siemens Ag, 1000 Berlin Und 8000 Muenchen Electroacoustic transducer with a diaphragm provided with a piezoelectric layer

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1160009B (en) * 1960-02-12 1963-12-27 Int Standard Electric Corp Electro-acoustic converter

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0074424A1 (en) * 1981-09-14 1983-03-23 Heinrich Andreas Peiker Electroacoustic, in particular electrodynamic, transducer protected from moisture and dirt and in particular from iron particles

Also Published As

Publication number Publication date
AU6790581A (en) 1981-09-03
DE3007808A1 (en) 1981-09-10
BR8101221A (en) 1981-09-01
US4376232A (en) 1983-03-08
FI810624L (en) 1981-08-30
JPS56134898A (en) 1981-10-21
ZA811320B (en) 1982-03-31
FI810624A7 (en) 1981-08-30

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