EP0308899A2 - Transducteur à ultrasons avec une caractéristique d'émission et réception astigmatique - Google Patents

Transducteur à ultrasons avec une caractéristique d'émission et réception astigmatique Download PDF

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Publication number
EP0308899A2
EP0308899A2 EP88115485A EP88115485A EP0308899A2 EP 0308899 A2 EP0308899 A2 EP 0308899A2 EP 88115485 A EP88115485 A EP 88115485A EP 88115485 A EP88115485 A EP 88115485A EP 0308899 A2 EP0308899 A2 EP 0308899A2
Authority
EP
European Patent Office
Prior art keywords
membrane
grooves
transducer according
bending 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.)
Withdrawn
Application number
EP88115485A
Other languages
German (de)
English (en)
Other versions
EP0308899A3 (fr
Inventor
Valentin Dipl.-Phys. Magori
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
Publication of EP0308899A2 publication Critical patent/EP0308899A2/fr
Publication of EP0308899A3 publication Critical patent/EP0308899A3/fr
Withdrawn legal-status Critical Current

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    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K9/00—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
    • G10K9/12—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated
    • G10K9/122—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated using piezoelectric driving means
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/26—Sound-focusing or directing, e.g. scanning
    • G10K11/32—Sound-focusing or directing, e.g. scanning characterised by the shape of the source
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K13/00—Cones, diaphragms, or the like, for emitting or receiving sound in general

Definitions

  • the present invention relates to an ultrasonic bending transducer, as specified in the preamble of claim 1.
  • a sensor for carrying out a distance measurement according to the ultrasound echo principle is known.
  • This sensor is intended to determine and display proximity distances between a vehicle and nearby obstacles.
  • It is a pot converter with a piezoceramic oscillator arranged in it.
  • damping material is provided on the inside of the diaphragm of this pot converter on two horizontal, opposite circular sections to prevent high-energy ultrasound or signal output.
  • the damping material is e.g. Soft rubber.
  • it is provided to arrange the pot converter in a horn.
  • the membrane of the pot converter is the bottom of the pot. Because the damping material is distributed asymmetrically to the normal to the membrane or the pot bottom, this converter has a correspondingly asymmetrical transmission and reception characteristic or transmission and reception lobe.
  • this pot converter one can imagine a connecting line between the portions of the damping material asymmetrically attached inside the pot converter. This connecting line runs perpendicular to the surface normal of the membrane (pot bottom). This connecting line and the surface normal mentioned form a plane. The sound propagation or the sound reception characteristic in this plane is essentially a single radiation lobe with the normal mentioned as the center line.
  • the radiation characteristic has a plurality of radiation lobes, of which the central radiation lobe, like the radiation lobe specified above, has the surface normal of the membrane as the center line.
  • the central radiation lobe like the radiation lobe specified above, has the surface normal of the membrane as the center line.
  • this vertical plane in addition to this center lobe, there is another radiation lobe on each side in the manner of secondary maxima.
  • the size of such a secondary maximum is essentially the same size as the central radiation lobe.
  • such a pot converter has a broad radiation field for transmission and / or reception in one plane (namely the vertical plane mentioned above). In the plane perpendicular to this, this transducer has a relatively narrow characteristic, so that an astigmatic sound characteristic results overall.
  • the object of the present invention is to provide a structure for a transducer with the most improved astigmatic radiation characteristic, which is easier and more reproducible to manufacture and which is free from aging.
  • damping material as is known, has the disadvantage that there is considerable scatter in the large series of the characteristic values of such transducers and / or adequate aging resistance cannot be achieved.
  • the invention is therefore based on the idea of giving the actual pot converter those characteristic properties which always ensure reproducible and / or reliably maintained predetermined characteristic values.
  • the membrane is designed to achieve the anisotropy of the sound radiation in such a way that it has anisotropic elastic properties in mutually perpendicular (main) directions lying in the plane of the membrane. Corresponding transition behavior is present in this membrane for the directions between these two main planes.
  • these anisotropic elastic properties are achieved in that the values of the speed of sound in the material of this membrane are substantially different from one another in these two main directions.
  • the pot converter can still have the round shape that is technically easy to manufacture.
  • these different sound velocities are brought about by mechanical changes in the surface of the membrane thereof. For example, the membrane is changed into the surface of the membrane by scoring, embossing, sawing or milling grooves and the like, the direction of these operations being in each case parallel to one another and parallel to the one main direction.
  • Damping materials can also be used for damping, without this being a contradiction to the above statements regarding the prior art.
  • material changes in the damping material have a far less serious and in particular practically no effect on the astigmatic radiation or reception property.
  • FIG. 1 shows a top view of the membrane of a pot transducer according to the invention, which has an astigmatic sound lobe for transmission and reception.
  • the membrane of the converter 1 is designated 2.
  • This membrane consists of e.g. a pan bottom, plate 11, made of piezoelectrically inactive material, preferably made of metal, and a plate 10 made of piezo material, such as e.g. Piezoceramic.
  • 3 denotes grooves or cracks (as one of the relevant configurations) which are located in the outer surface of the membrane 2 of the pot converter 1.
  • N denotes the normal direction of the membrane 2, which is also the central axis of the sound lobe.
  • Figure 2 shows a side view of the transducer 1, namely this view in section. With 7 the edge of this pot converter is designated.
  • the grooves or cracks 3, for example embossed, sawn or milled into the surface of the membrane 2, can be clearly seen.
  • the disc 10 for example glued on, on the inside of the pot converter 1 on the surface of the membrane 2 and made of polarized piezoceramic, for example a lead zirconate titanate is the piezoelectric vibrator.
  • 14 is an electrode and 12 is an adhesive.
  • FIG. 3 shows an image corresponding to FIG. 2 with grooves or cracks 13 provided on the inside of the pot converter 101 in the surface of the membrane 2. These grooves or cracks 13 can be used instead of the grooves or cracks 3 or together with such grooves or Cracks 3 may be provided. In any case, grooves 3 and 13 are at least substantially parallel.
  • the disk of piezoceramic belonging to the membrane 2 is designated by 110. The associated electrode is not shown.
  • the grooves, crevices 3, 13 can be distributed uniformly equidistantly over the surface. They can preferably be arranged symmetrically to the center line (parallel to direction 4), distributed over direction 5, as shown in FIG. 1. Analogously, this distribution can also be non-uniformly dense, as can be seen from FIG. 1.
  • These grooves or cracks 3, 13 preferably extend from edge to edge of the plate 11 and / or the plate 10. However, they can also begin or end at a distance from such an edge. They can also have interruptions in their longitudinal direction.
  • a transducer according to the invention the coupling of the vibration modes of the two directions 4 and 5 is so large that a mode spectrum can essentially be observed for the round pot transducer that has a fundamental frequency and harmonics that occur in pairs. These harmonics can be clearly distinguished from one another in a converter according to the invention.
  • a transducer according to the invention can be operated reliably on one of the paired harmonics without the risk that the transducer could jump into the vibration of the other harmonic.
  • FIG. 4 shows the basic distribution of the sound lobe in the middle plane, which is perpendicular to the representation plane of FIG. 1 and parallel to direction 4.
  • FIG. 5 shows the sound lobe in the central plane perpendicular to the drawing plane and the direction 4. It can be clearly seen that the radiation lobe of FIG. 4 is considerably wider than that of FIG. 5, i.e. the transducer according to FIGS. 1, 2 and 3 covers a wide field in a plane containing the direction 4, whereas in the direction perpendicular thereto the transducer has such a narrow lobe that locations further away from its axis direction are no longer detected by the astigmatic radiation lobe .
  • a transducer of the type according to the invention is particularly suitable as a detection transducer for land and watercraft, in which broad “illumination” is desired parallel to the driving level, but on the other hand, as little sound as possible is to be emitted (and received back as an echo)
  • Such a transducer can be used equally as a transmitter and receiver.
  • Another advantage of a transducer according to the invention is that the choice, the distribution and the dimensioning of the grooves or cracks 3 in the surface of the membrane 2 make a relative This means that for a transducer according to the invention, blind directions within the overall beam lobe can be minimized, in the direction of which the transducer has a very narrow obstacle, for example a lamppost , could not detect.
  • a preferred application of a converter according to the invention is that as a reversing aid, in particular for heavy vehicles with a rearward view or for vehicles (excavators and the like) that frequently move back and forth.
  • the membrane or possibly also the pot will preferably have a circular shape.
  • a rectangular or preferably oval shape can also be provided, namely depending on which vibration behavior of the membrane is preferred.
  • the oval shape can be an elliptical shape. But it can also take the form of an ancient Egyptian cartridge, i.e. a circle that is elongated in one direction.
  • the membrane can be dimensioned so large in relation to the desired oscillation frequency that (as already mentioned above) the resonance frequency of its (a) first harmonic is used.
  • the ceramic plate so large that it, when attached to the plate of the membrane, only reaches from the center up to the vibration node line (e.g. vibration node circle) of this first harmonic. It is therefore unnecessary to design the plate or the arrangement and shape of the electrodes on the plate in such a way that corresponding portions of the same (as a transmitter) are excited piezoelectrically in the required manner in antiphase.
  • this converter has e.g. a pot with a diameter of 25 mm and a thickness of 0.4 mm of the plate 11 of the membrane 2.
  • the ceramic plate 10 has a thickness of 0.25 or 0.4 mm and a diameter of approximately 9 mm (diameter of the oscillation node circle). Without grooves, this converter has a natural frequency at 40 kHz. With grooves 3 according to the invention with a depth of 0.2 mm and a width of about 0.2 mm at a distance of 1 mm, a natural frequency of 36 to 33 kHz results.
  • angles of the radiation in directions 4 and 5, that is the extent of the astigmatism, are 120 to 140 ° to 60 to 65 ° in such a transducer.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Transducers For Ultrasonic Waves (AREA)
EP88115485A 1987-09-25 1988-09-21 Transducteur à ultrasons avec une caractéristique d'émission et réception astigmatique Withdrawn EP0308899A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19873732410 DE3732410A1 (de) 1987-09-25 1987-09-25 Ultraschallwandler mit astigmatischer sende-/empfangscharakteristik
DE3732410 1987-09-25

Publications (2)

Publication Number Publication Date
EP0308899A2 true EP0308899A2 (fr) 1989-03-29
EP0308899A3 EP0308899A3 (fr) 1990-03-14

Family

ID=6336916

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88115485A Withdrawn EP0308899A3 (fr) 1987-09-25 1988-09-21 Transducteur à ultrasons avec une caractéristique d'émission et réception astigmatique

Country Status (3)

Country Link
EP (1) EP0308899A3 (fr)
JP (1) JPH01119200A (fr)
DE (1) DE3732410A1 (fr)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0393225A1 (fr) * 1989-04-20 1990-10-24 Siemens Aktiengesellschaft Détection ultrasonique pour véhicule à faisceau ultrasonique dirigé transversalement à la direction de conduite
DE3939387A1 (de) * 1989-11-29 1991-06-06 Swf Auto Electric Gmbh Abstandswarnanlage, insbesondere fuer kraftfahrzeuge
US5229748A (en) * 1989-04-12 1993-07-20 Siemens Aktiengesellschaft Monitoring system for monitoring the window panes of an interior, for example a motor vehicle interior
EP0678853A2 (fr) 1994-04-21 1995-10-25 ITT Automotive Europe GmbH Transducteur à ultrason ayant une charactéristique de radiation asymmétrique
DE10138892A1 (de) * 2001-08-08 2003-02-20 Valeo Schalter & Sensoren Gmbh Ultraschallwandler
EP1906383A1 (fr) * 2006-09-29 2008-04-02 Tung Thih Electronic Co., Ltd. Appareil de transducteur à ultrasons
DE102010002282A1 (de) 2010-02-24 2011-08-25 Lisa Dräxlmaier GmbH, 84137 Innenausstattungsteil sowie Außenverkleidungsteil eines Fahrezeugs mit einem Ultraschallsensor
DE102015205950A1 (de) * 2015-04-01 2016-10-06 Volkswagen Aktiengesellschaft Vorrichtung, Verfahren und Computerprogramm zur Erfassung akustischer Steueranweisungen
WO2016184952A1 (fr) * 2015-05-20 2016-11-24 Valeo Schalter Und Sensoren Gmbh Capteur à ultrasons pour un véhicule automobile, véhicule automobile ainsi que procédé de fabrication d'un capteur à ultrasons
WO2017089609A3 (fr) * 2015-11-26 2017-09-28 Elmos Semiconductor Aktiengesellschaft Élément oscillant pour un transducteur ultrasonore à résonance multiple
CN114728311A (zh) * 2019-09-12 2022-07-08 艾科索成像公司 经边缘凹槽、虚拟枢轴和自由边界提高mut耦合效率和带宽

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10009129A1 (de) * 2000-02-26 2001-08-30 Volkswagen Ag Ultraschallsensor
JP4724561B2 (ja) * 2005-01-18 2011-07-13 株式会社川上鉄工所 塗布装置
JP4618165B2 (ja) * 2006-03-06 2011-01-26 株式会社デンソー 超音波センサ
EP2011113A4 (fr) * 2006-04-19 2012-06-20 Commw Scient Ind Res Org Systèmes de transducteurs ultrasonores
JP5910507B2 (ja) * 2010-12-28 2016-04-27 日本電気株式会社 電気音響変換器
JP5023244B1 (ja) * 2012-01-13 2012-09-12 浩平 速水 振動力発電装置
JP5458421B2 (ja) * 2012-05-07 2014-04-02 浩平 速水 振動力発電装置
JP5228136B1 (ja) * 2012-11-21 2013-07-03 浩平 速水 振動力発電装置
DE102015106240A1 (de) 2015-04-23 2016-10-27 Valeo Schalter Und Sensoren Gmbh Ultraschallsensor für ein Kraftfahrzeug mit einer Durchgangsöffnungen aufweisenden Membran, Verkleidungsanordnung sowie Kraftfahrzeug

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2716708A (en) * 1950-11-17 1955-08-30 Nat Res Dev Apparatus for launching ultrasonic waves
FR2293844A1 (fr) * 1974-12-02 1976-07-02 Barcus Lester Transducteur acoustique
EP0037620A1 (fr) * 1980-04-07 1981-10-14 North American Philips Corporation Dispositif d'adaptation d'impédance acoustique
EP0075302A1 (fr) * 1981-09-23 1983-03-30 Egon Gelhard Dispositif pour mesurer des distances au moyen d'échos ultrasonores
JPS59230224A (ja) * 1983-06-13 1984-12-24 三菱電機株式会社 ガス絶縁開閉装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2855143C2 (de) * 1978-12-20 1980-11-06 Siemens Ag, 1000 Berlin Und 8000 Muenchen Verfahren zur Herstellung eines Ultraschallwandlers und entsprechend hergestellter Wandler
JPS5642493A (en) * 1979-09-13 1981-04-20 Toray Ind Inc Acoustic-wave converging type transducer using high-molecular piezoelectric body
DE3407980A1 (de) * 1983-04-20 1984-10-25 Tadashi Tokio/Tokyo Sawafuji Kristallschallerzeuger

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2716708A (en) * 1950-11-17 1955-08-30 Nat Res Dev Apparatus for launching ultrasonic waves
FR2293844A1 (fr) * 1974-12-02 1976-07-02 Barcus Lester Transducteur acoustique
EP0037620A1 (fr) * 1980-04-07 1981-10-14 North American Philips Corporation Dispositif d'adaptation d'impédance acoustique
EP0075302A1 (fr) * 1981-09-23 1983-03-30 Egon Gelhard Dispositif pour mesurer des distances au moyen d'échos ultrasonores
JPS59230224A (ja) * 1983-06-13 1984-12-24 三菱電機株式会社 ガス絶縁開閉装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Band 102, Nr. 90 (P-503), 2. Oktober 1982; & JP-A-59 230 224 (HITACHI LTD) 28-05-1986 *

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5229748A (en) * 1989-04-12 1993-07-20 Siemens Aktiengesellschaft Monitoring system for monitoring the window panes of an interior, for example a motor vehicle interior
EP0393225A1 (fr) * 1989-04-20 1990-10-24 Siemens Aktiengesellschaft Détection ultrasonique pour véhicule à faisceau ultrasonique dirigé transversalement à la direction de conduite
DE3939387A1 (de) * 1989-11-29 1991-06-06 Swf Auto Electric Gmbh Abstandswarnanlage, insbesondere fuer kraftfahrzeuge
EP0678853A2 (fr) 1994-04-21 1995-10-25 ITT Automotive Europe GmbH Transducteur à ultrason ayant une charactéristique de radiation asymmétrique
EP0678853A3 (fr) * 1994-04-21 1997-05-21 Teves Gmbh Alfred Transducteur à ultrason ayant une charactéristique de radiation asymmétrique.
DE4413894C2 (de) * 1994-04-21 2002-12-12 Teves Gmbh Alfred Biegewandler in Topfform
DE10138892A1 (de) * 2001-08-08 2003-02-20 Valeo Schalter & Sensoren Gmbh Ultraschallwandler
EP1906383A1 (fr) * 2006-09-29 2008-04-02 Tung Thih Electronic Co., Ltd. Appareil de transducteur à ultrasons
DE102010002282A1 (de) 2010-02-24 2011-08-25 Lisa Dräxlmaier GmbH, 84137 Innenausstattungsteil sowie Außenverkleidungsteil eines Fahrezeugs mit einem Ultraschallsensor
WO2011104185A1 (fr) 2010-02-24 2011-09-01 Lisa Dräxlmaier GmbH Partie d'équipement intérieur et partie d'habillage extérieur d'un véhicule avec un capteur à ultrasons
US9340167B2 (en) 2010-02-24 2016-05-17 Lisa Draexlmaier Gmbh Interior trim part and exterior facing part of a vehicle having an ultrasonic sensor
DE102015205950A1 (de) * 2015-04-01 2016-10-06 Volkswagen Aktiengesellschaft Vorrichtung, Verfahren und Computerprogramm zur Erfassung akustischer Steueranweisungen
DE102015205950B4 (de) 2015-04-01 2017-02-02 Volkswagen Aktiengesellschaft Vorrichtung, Verfahren und Computerprogramm zur Erfassung akustischer Steueranweisungen
WO2016184952A1 (fr) * 2015-05-20 2016-11-24 Valeo Schalter Und Sensoren Gmbh Capteur à ultrasons pour un véhicule automobile, véhicule automobile ainsi que procédé de fabrication d'un capteur à ultrasons
WO2017089609A3 (fr) * 2015-11-26 2017-09-28 Elmos Semiconductor Aktiengesellschaft Élément oscillant pour un transducteur ultrasonore à résonance multiple
CN114728311A (zh) * 2019-09-12 2022-07-08 艾科索成像公司 经边缘凹槽、虚拟枢轴和自由边界提高mut耦合效率和带宽

Also Published As

Publication number Publication date
JPH01119200A (ja) 1989-05-11
DE3732410A1 (de) 1989-04-13
EP0308899A3 (fr) 1990-03-14

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