EP0178346A1 - Ultrasonic transducer - Google Patents

Ultrasonic transducer Download PDF

Info

Publication number
EP0178346A1
EP0178346A1 EP84112594A EP84112594A EP0178346A1 EP 0178346 A1 EP0178346 A1 EP 0178346A1 EP 84112594 A EP84112594 A EP 84112594A EP 84112594 A EP84112594 A EP 84112594A EP 0178346 A1 EP0178346 A1 EP 0178346A1
Authority
EP
European Patent Office
Prior art keywords
top plate
side plate
ultrasonic transducer
cylindrical side
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.)
Granted
Application number
EP84112594A
Other languages
German (de)
French (fr)
Other versions
EP0178346B1 (en
Inventor
Toshiharu Ito
Eiji Ozeki
Kozo Okada
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.)
Niterra Co Ltd
Original Assignee
NGK Spark Plug Co Ltd
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=27284612&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0178346(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority claimed from JP2434684U external-priority patent/JPS60136599U/en
Priority claimed from JP2648784U external-priority patent/JPS60139399U/en
Priority claimed from JP5034784U external-priority patent/JPS60163899U/en
Application filed by NGK Spark Plug Co Ltd filed Critical NGK Spark Plug Co Ltd
Priority to DE8484112594T priority Critical patent/DE3486035D1/en
Publication of EP0178346A1 publication Critical patent/EP0178346A1/en
Application granted granted Critical
Publication of EP0178346B1 publication Critical patent/EP0178346B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • B06B1/0644—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using a single piezoelectric element
    • B06B1/0662—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using a single piezoelectric element with an electrode on the sensitive surface
    • B06B1/067—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using a single piezoelectric element with an electrode on the sensitive surface which is used as, or combined with, an impedance matching layer
    • 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
    • G10K11/002—Devices for damping, suppressing, obstructing or conducting sound in acoustic devices
    • 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
    • G10K11/02—Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00—Gas-discharge or vapour-discharge lamps
    • H01J61/02—Details
    • H01J61/30—Vessels; Containers
    • H01J61/32—Special longitudinal shape, e.g. for advertising purposes
    • H01J61/327—"Compact"-lamps, i.e. lamps having a folded discharge path

Definitions

  • This invention relates to an ultrasonic transducer capable of transmitting and / or receiving ultrasonic waves.
  • FIG. 15 Such a transducer is shown in Fig. 15, in which reference numeral 1 designates a swing case which is formed of metal such as stainless steel and is composed of a cylindrical side plate 1b and an upper plate 1a which is so at one end of the side plate 1b it is intended to complete them.
  • 2 designates a piezoelectric ceramic disk which is connected to the inner wall of the top plate 1a for the purpose of a common vibration, thereby producing an integrated connection.
  • the ceramic disc 2 is provided on its opposite sides with a pair of electrodes 2a and 2b.
  • the open end section of the oscillating housing 1 is closed by a cover plate 3.
  • a pair of end terminal pins 4a and 4b are provided, one end of which is lead wire 5a and 5b are connected to the electrodes 2a and 2b.
  • 6 denotes an insulating layer, which is formed, for example, from an epoxy resin in order to seal the oscillating housing 1.
  • the piezoelectric ceramic disk 2 When an electric field is applied to the pins 4a and 4b to apply an AC voltage between the opposing electrodes 2a and 2b, the piezoelectric ceramic disk 2 is excited to longitudinal or bending vibrations so that an ultrasonic wave is generated from the top plate 1a in which the integrated ceramic disc 2 is integrated. On the other hand, when the top plate 1a receives an ultrasonic wave, the piezoelectric ceramic disk 2 deforms such that an output with an intensity corresponding to the incident ultrasonic wave is output from the electrodes 2a and 2b.
  • the ultrasonic transducer of the type mentioned above has proven to be poorly suited for use as a proximity switch or sensor for the removal of a substance. Since the vibrating housing is formed from metal, the wave-transmitting and receiving section, which is formed from the top plate 1a and the piezoelectric ceramic disk 2, has such a high mechanical quality factor Q that, as shown in FIG. 16a, the transducer exhibits pulse characteristics, which have a long pulse decay time. It is therefore possible that when the transducer receives an ultrasound wave that has been reflected from the nearest substance during the transmission of the ultrasound wave, it is unable to function as a sensor or detector.
  • the resulting transducer has superior wave transmission and reception properties, in particular an improved response behavior, compared to that transducer whose oscillating housing is made of a non-porous plastic.
  • an ultrasonic transducer having a vibrating housing member having a cylindrical side plate and a shaft transmitting and receiving top plate provided at one end of the side plate, a piezoelectric element which is integrally formed with the inner wall of the Top plate is connected, and electrodes, which are arranged on the piezoelectric element, so that ultrasonic waves can be generated from the top plate when an electric field is applied to the electrodes, and / or an electrical output from the electrodes is given when the top plate Receives ultrasonic waves, wherein the top plate is made of a porous plastic.
  • FIGS. 1 and 2 form an embodiment of the ultrasonic transducer according to the invention.
  • those components which correspond to those in FIG. 15 are designated with the same reference numerals, to which, however, 10 has been added.
  • the exemplary embodiment shown in FIGS. 1 and 2 differs from the conventional converter shown in FIG. 15 in that the oscillating housing 11 of FIGS. 1 and 2 is formed from a porous plastic.
  • a piezoelectric element 12 with electrodes 12a and 12b is bonded to the inner surface of an upper plate 11a of the housing part 11 to form an integrated component.
  • the housing part 11 has a cylindrical side plate 11b which is integrally connected to the top plate 11a.
  • the open end portion of the housing part 11 is provided with a cover plate 13 to which a pair of terminal pins 14a and 14b are attached.
  • Lead wires 15a and 15b extend between electrode 12a and pin 14a and between electrode 12b and pin 14b, respectively.
  • the cover plate 13 is covered with an insulating layer 16.
  • Denoted at 17 is an insulator which is provided when the cover plate is formed from an electrical conductor in order to provide the insulation between the two connection pins 14a and 14b.
  • both the top plate 11a and the side plate 11b are formed from porous plastic.
  • porous plastic as used herein is intended to include a synthetic polymeric material that has a large number of closed cells distributed within the polymeric material.
  • suitable porous plastics are synthetic polymer materials in which a large number of glass microballoons are distributed, and foamed synthetic polymer materials materials which are produced using foaming agents in a conventional manner.
  • the porous plastic preferably has an average pore diameter which is between 50 and 100 ⁇ .
  • suitable polymer materials are epoxy resins, polyolefin resins, styrene resins, acrylic resins and vinyl chloride resins.
  • the vibrating case 11 of the present invention is molded from porous plastic, so that the Q m of the wave transmitting and receiving portion of the ultrasonic transducer of this invention is low, so that the pulse rise and fall times can be shortened as shown in Fig. 16b is.
  • the reduction in the pulse decay time advantageously leads to a reduction in the reverberation time.
  • the top plate 11a contains a relatively large amount of air, the acoustic impedance of the top plate 11a approaches that of air. Therefore, the fitting conditions between the top plate 11a and the ambient air are improved, which leads to an improvement in response, that is, a more intense output can be obtained after receiving an ultrasonic wave of constant intensity.
  • the conventional ultrasonic transducer whose housing is made of stainless steel, a pulse rise time of 0.5 ms, a pulse fall time of 2.0 ms and an output voltage of 0.4 V.
  • An ultrasonic transducer, the oscillating housing of which is made of non-porous epoxy resin provides a pulse rise time of 0.2 mA, a pulse fall time of 1.2 ms and an output voltage of 2.6 V.
  • the oscillating body is formed of an epoxy resin, in which a large Distributed number of glass microballoons that have a diameter of 50 to 100 microns, there is a pulse rise and fall time of 0.2 or 1.2 ms, and the output voltage is 6.4 V.
  • the thickness of the top plate 11 a of the vibrating housing 11 is about 1/4 of the wavelength of the speed of sound of the top plate 11 a, for the reason of achieving the best response.
  • both the top plate 11a and the cylindrical side plate 11b are molded from solid plastic. A similar improvement can be obtained even if the top plate is molded from a porous plastic alone.
  • a cylindrical side plate 11b is integrally provided at one end with a top plate 11a molded from porous plastic of the type just mentioned.
  • the other designs of the transducer are substantially the same as in the embodiment of Figs. 1 and 2, and their detailed explanation is omitted here.
  • 4 and 5 depict exemplary embodiments similar to that of FIG. 3.
  • the outer periphery of the top plate 11a is in contact with the inner surface of the cylindrical side plate 11b.
  • the end portion of the top plate 11a and the side plate 11b are cut together diagonally for abutment engagement.
  • the top plate 11a can be attached to the side plate 11b by any known means, such as glue.
  • the cylindrical side plate 11b is preferably molded from a material whose acoustic impedance is greater than that of the top plate 11a, for the purpose of achieving a reduction in reverberation time.
  • a suitable material for the side plate 11b are plastics, metals and ceramic materials. If both the top plate and the side plate of the vibrating housing are molded from a porous plastic, then the vibration on the side of the vibrating housing 11 is not completely damped, and the reverberation time cannot be reduced below a certain limit.
  • the vibration of the top plate 11a at the interface between the top plate 11a and the side plate 11b reflects and distributes and is prevented from proceeding to the side plate 11b.
  • the reverberation time becomes shorter compared to the transducer in which the vibrating housing is completely molded from porous plastic.
  • the ultrasonic transducer whose oscillating housing is formed from porous plastic with an acoustic impedance of 1 x 3000 g / cm z s, shows a wave-transmitting pulse characteristic as shown by line 20 in FIG. 6.
  • the vibrating housing is formed from a cylindrical side plate, which is formed from stainless steel with an acoustic impedance of 7.8 x 5000 g / cm 2 s, and an upper plate, which is made of a porous plastic with 1 x 3000 g / cm z s is shaped on acoustic impedance, then the transducer provides the pulse characteristic as shown by the broken line 21 in FIG. 6. This means that the reverberation time can be reduced to less than 1.0 ms.
  • Such a reduction in reverberation time can also be accomplished by providing an integrated tubular part or parts on the outer and / or inner circumference of the cylindrical side plate of the transducer shown in Figs. 1 and 2, wherein the tubular part has a higher acoustic impedance than the cylindrical side plate.
  • a tubular member 18 is provided within a swing housing and bonded to the inner periphery of its cylindrical side plate 11b.
  • the tubular member 18 is adhered to the outer periphery of the side plate 11b.
  • tubular member 18 improves wire eieschwingungsdämpfende effect on the side of the oscillating body, in order to reduce the reverberation time.
  • Attachment of tubular member 18 to side plate 11b can be accomplished by any known means, such as glue.
  • the tubular part 1 is provided within the housing 11, then it is expedient to design the tubular part as an elastic tube, generally a metal tube which has a slot 18a which extends parallel to the axis of the tube.
  • the tube 18 has a larger outer diameter than the inner diameter of the side plate 11b in the free state.
  • the tubular member 18 is provided outside the housing 11, it is possible to use an elastic tube, such as a rubber tube, which has a smaller inner diameter than the outer diameter of the cylindrical side plate 11b. By fitting the rubber tube 18 around the circumference of the side plate 11b, the tube is held in pressure contact with the side plate 11b.
  • the elastic tubular member it is not necessary for the tubular member to be made of a material having a greater acoustic impedance than the side plate 11b because of the fact that the side plate 11b is always the same. Forces in the direction perpendicular to the axis of the cylindrical. The side plate 11b is exposed and is prevented from vibrating.
  • the thickness of the top plate 11a is suddenly changed at a ring portion near the outer periphery of the piezoelectric disk 12 by the transverse vibration that is circumferential be wedge-shaped).
  • the height of the raised portion 11c and the depth of the annular groove 11d are not larger than 1/3 of the thickness D of the top plate 11a to prevent a decrease in responsiveness.

Abstract

The invention relates to an ultrasonic transducer with a vibration casing (11) consisting of a cylindrical side plate (11b) and a top plate (11a) fitted on one face of the side plate (11b) and transmitting and receiving waves, a piezoelectric element (12) which is connected to the inside of the top plate (11a) to form an integral component and ensure that it vibrates with the plate, and electrodes (12a, b) arranged on the piezoelectric element (12) so that soundwaves can be generated from the top plate (11a) if an electric field is applied to the electrodes (12a,b), and/or an electric output is supplied from the electrodes if the top plate (11a) receives ultrasonic waves. The improvement covers the vibration casing, at least the top plate (11a) of which is moulded from porous plastics material. <IMAGE>

Description

Diese Erfindung betrifft einen Ultraschallwandler, der imstande ist, Ultraschallwellen zu senden und/oder zu empfangen.This invention relates to an ultrasonic transducer capable of transmitting and / or receiving ultrasonic waves.

Es sind in der Technik vielfältige Arten von Ulcraschallwandlern bekannt. Ein solcher Wandler ist in Fig. 15 gezeigt, in welcher das Bezugszeichen 1 ein Schwinggehäuse bezeichnet, welches aus Metall, etwa rostfreiem Stahl, geformt ist und aus einer zylindrischen Seitenplatte 1b und einer Oberplatte 1a zusammengesetzt ist, welche am einen Ende der Seitenplatte 1b so vorgesehen ist, daß sie diese abschließt. Mit 2 ist eine piezoelektrische Keramikscheibe bezeichnet, die unter Herstellung einer integrierten Verbindung mit der Innenwand der Oberplatte 1a zur gemeinsamen Schwingung hiermit verbunden ist. Die keramische Scheibe 2 ist an ihren gegenüberliegenden Seiten mit einem Paar Elektroden 2a und 2b versehen. Der offene Endabschnitt des Schwinggehäuses 1 ist durch eine Abdeckplatte 3 verschlossen. In der Abdeckplatte 3 ist ein Paar Endanschlußstifte 4a und 4b vorgesehen, deren eine Enden durch Leitungsdrähte 5a und 5b mit den Elektroden 2a bzw. 2b verbunden sind. Mit 6 ist eine Isolierschicht bezeichnet, die beispielsweise aus einem Epoxidharz gebildet ist, um das Schwinggehäuse 1 abzudichten.Various types of ultrasonic transducers are known in the art. Such a transducer is shown in Fig. 15, in which reference numeral 1 designates a swing case which is formed of metal such as stainless steel and is composed of a cylindrical side plate 1b and an upper plate 1a which is so at one end of the side plate 1b it is intended to complete them. 2 designates a piezoelectric ceramic disk which is connected to the inner wall of the top plate 1a for the purpose of a common vibration, thereby producing an integrated connection. The ceramic disc 2 is provided on its opposite sides with a pair of electrodes 2a and 2b. The open end section of the oscillating housing 1 is closed by a cover plate 3. In the cover plate 3, a pair of end terminal pins 4a and 4b are provided, one end of which is lead wire 5a and 5b are connected to the electrodes 2a and 2b. 6 denotes an insulating layer, which is formed, for example, from an epoxy resin in order to seal the oscillating housing 1.

Wenn ein elektrisches Feld an die Anschlußstifte 4a und 4b angelegt wird, um eine Wechselspannung zwischen den gegenüberliegenden Elektroden 2a und 2b aufzubringen, dann wird die piezoelektrische Keramikscheibe 2 zu Längs-oder Biegeschwingungen angeregt, so daß eine Ultraschallwelle von der Oberplatte 1a erzeugt wird, in welche die angeklebte Keramikscheibe 2 integriert ist. Wenn andererseits die Oberplatte 1a eine Ultraschallwelle empfängt, dann verformt sich die piezoelektrische Keramikscheibe 2 derart, daß ein Ausgang mit einer Intensität, welche der einfallenden Ultraschallwelle entspricht, von den Elektroden 2a und 2b abgegeben wird.When an electric field is applied to the pins 4a and 4b to apply an AC voltage between the opposing electrodes 2a and 2b, the piezoelectric ceramic disk 2 is excited to longitudinal or bending vibrations so that an ultrasonic wave is generated from the top plate 1a in which the integrated ceramic disc 2 is integrated. On the other hand, when the top plate 1a receives an ultrasonic wave, the piezoelectric ceramic disk 2 deforms such that an output with an intensity corresponding to the incident ultrasonic wave is output from the electrodes 2a and 2b.

Der Ultraschallwandler der oben erwähnten Art hat sich jedoch als schlecht geeignet zur Verwendung als Näherungsschalter oder Meßfühler für die Entfernung einer Substanz erwiesen. Da das Schwinggehäuse aus Metall geformt ist, hat der Wellen sendende und empfangende Abschnitt, der aus der Oberplatte 1a und der piezoelektrischen Keramikscheibe 2 gebildet ist, einen so hohen mechanischen Gütefaktor Q , daß, wie in Fig. 16a gezeigt, der Wandler Impulscharakteristiken zeigt, die eine lange Impuls-Abfallzeit aufweisen. Es ist deshalb möglich, daß dann, wenn der Wandler eine Ultraschallwelle empfängt, die von der nächstgelegenen Substanz reflektiert wurde, und zwar während des Sendevorgangs der Ultraschallwelle,er nicht fähig ist, als Meßfühler bzw. Spürgerät zu arbeiten.However, the ultrasonic transducer of the type mentioned above has proven to be poorly suited for use as a proximity switch or sensor for the removal of a substance. Since the vibrating housing is formed from metal, the wave-transmitting and receiving section, which is formed from the top plate 1a and the piezoelectric ceramic disk 2, has such a high mechanical quality factor Q that, as shown in FIG. 16a, the transducer exhibits pulse characteristics, which have a long pulse decay time. It is therefore possible that when the transducer receives an ultrasound wave that has been reflected from the nearest substance during the transmission of the ultrasound wave, it is unable to function as a sensor or detector.

Es hat sich herausgestellt, daß dann, wenn das Schwinggehäuse aus einem Kunststoff gebildet ist, etwa aus Epoxidharz, das Q m des Wellen sendenden und empfangenden Abschnitts niedrig wird, und sowohl die Impulsanstiegzeit als auch die Impulsabfallzeit kurz werden, wie in Fig. 16b gezeigt. Außerdem ergibt sich auch eine Verbesserung in der Intensität der Ausgangsspannung, die in Abhängigkeit vom Empfang einer Ultraschallwelle abgegeben wird.It has been found that when the vibrating case is made of a plastic such as epoxy resin, the Q m of the wave transmitting and receiving section becomes low, and both the pulse rise time and the pulse fall time become short, as in Fig. 16b shown. In addition, there is also an improvement in the intensity of the output voltage, which is emitted as a function of the reception of an ultrasonic wave.

Infolge weiterer Untersuchungen hat sich herausgestellt daß dann, wenn die Oberplatte des Schwinggehäuses aus einem porösen Kunststoff, etwa aufgeschäumtem Epoxidharz, gebildet ist, der resultierende Wandler überlegene Wellen-Sende- und -E.mpfangs-Eigenschaften aufweist, und zwar besonders ein verbessertes Ansprechverhalten, verglichen mit jenem Wandler, dessen Schwinggehäuse aus einem nicht porösen Kunststoff gebildet ist.As a result of further investigations, it was found that if the upper plate of the vibrating housing is formed from a porous plastic, such as foamed epoxy resin, the resulting transducer has superior wave transmission and reception properties, in particular an improved response behavior, compared to that transducer whose oscillating housing is made of a non-porous plastic.

In Übereinstimmung mit der vorliegenden Erfindung ist ein Ultraschallwandler vorgesehen, der ein Schwinggehäuseteil mit einer zylindrischen Seitenplatte und einer Wellen sendenden und empfangenden Oberplatte aufweist, die am einen Ende der Seitenplatte vorgesehen ist, einem piezoelektrischen Element, das unter Bildung eines einheitlichen Teiles mit der Innenwand der Oberplatte verbunden ist, sowie Elektroden, die am piezoelektrischen Element angeordnet sind, so daß Ultraschallwellen von der Oberplatte dann erzeugt werden können, wenn ein elektrisches Feld an die Elektroden angelegt wird, und/ oder ein elektrischer Ausgang von den Elktroden abgegeben wird, wenn die Oberplatte Ultraschallwellen empfängt, wobei die Oberplatte aus einem porösen Kunststoff gebildet ist.In accordance with the present invention, there is provided an ultrasonic transducer having a vibrating housing member having a cylindrical side plate and a shaft transmitting and receiving top plate provided at one end of the side plate, a piezoelectric element which is integrally formed with the inner wall of the Top plate is connected, and electrodes, which are arranged on the piezoelectric element, so that ultrasonic waves can be generated from the top plate when an electric field is applied to the electrodes, and / or an electrical output from the electrodes is given when the top plate Receives ultrasonic waves, wherein the top plate is made of a porous plastic.

Die bevorzugten Ausfuhrunsbeispiele des erfindungsgemäßen Ultraschallwandlers werden nun unter Bezugnahme auf die beigefügten Zeichnungen beschrieben; in diesen ist:

  • Fig. 1 eine teilweise geschnittene Draufsicht welche schematisch ein Ausführungsbeispiel des Ultraschallwandlers der vorliegenden Erfindung zeigt,
  • Fig. 2 die Ansicht eines Aufrisses, der längs der Linie II-II in Fig. 1 vorgenommen wurde,
  • Fig. 3 die Ansicht eines Aufrisses ähnlich Fig. 2, welche schematisch jedoch ein anderes Ausführungsbeispiel der vorliegenden Erfindung zeigt,
  • Fig. 4 die Ansicht eines Teilaufrisses ähnlich Fig. 3, der ein anderes Ausführungsbeispiel der Fig. 3 zeigt,
  • Fig. 5 eine Ansicht ähnlich jener der Fig. 4, wobei eine noch weitere Alternativausführung der Fig. 3 gezeigt ist,
  • Fig. 6 ein Diagramm, welches die Impulscharakteristiken zeigt,
  • Fig. 7 ein Aufriß ähnlich Fig. 2, der schematisch ein weiteres Ausführungsbeispiel der vorliegenden Erfindung zeigt,
  • Fig. 8 eine Ansicht ähnlich Fig. 7, wobei ein weiteres Ausführungsbeispiel der vorliegenden Erfindung gezeigt ist,
  • Fig. 9 eine Perspektivansicht, die schematisch ein elastisches Metallrohr zeigt, welches in das Schwinggehäuse zum Verringern der Reflexions- bzw. Nachhallzeit eingeführt werden soll,
  • Fig. 10 ein Aufriß ähnlich Fig. 2, der schematisch ein weiteres Ausführungsbeispiel der vorliegenden Erfindung zeigt,
  • Fig. 11 bis 13 jeweils ein Teilaufriß, die schematisch Alternativausführungen der Fig. 10 zeigen,
  • Fig. 14 ein Richtwirkungsdiagramm des erfindungsgemäßen Ultraschallwandlers,
  • Fig. 15 ein Aufriß, der einen herkömmlichen Ultraschallwandler zeigt, und
  • Fig. 16a und 16b jeweils ein Diagramm, welches die Impulscharakteristiken des herkömmlichen Wandlers bzw. der vorliegenden Erfindung zeigt.
The preferred exemplary embodiments of the ultrasonic transducer according to the invention will now be described with reference to the accompanying drawings; in these is:
  • 1 is a partially sectional plan view schematically showing an embodiment of the ultrasonic transducer of the present invention,
  • 2 is a view of an elevation taken along the line II-II in Fig. 1,
  • 3 is a view of an elevation similar to FIG. 2, but schematically showing another embodiment of the present invention;
  • 4 is a view of a partial elevation similar to FIG. 3, showing another embodiment of FIG. 3,
  • 5 is a view similar to that of FIG. 4, showing yet another alternative embodiment of FIG. 3,
  • 6 is a diagram showing the pulse characteristics.
  • 7 is an elevation similar to FIG. 2 schematically showing another embodiment of the present invention;
  • 8 is a view similar to FIG. 7, showing another embodiment of the present invention,
  • 9 is a perspective view schematically showing an elastic metal pipe to be inserted into the swing case to reduce the reflection time.
  • 10 is an elevation similar to FIG. 2 schematically showing another embodiment of the present invention;
  • 11 to 13 each a partial elevation, which schematically show alternative designs of FIG. 10,
  • 14 is a directional diagram of the ultrasonic transducer according to the invention,
  • 15 is an elevation showing a conventional ultrasonic transducer, and
  • 16a and 16b are each a diagram showing the pulse characteristics of the conventional transducer and the present invention, respectively.

Die Fig. 1 und 2 bilden ein Ausführungsbeispiel des erfindungsgemäßen Ultraschallwandlers . In den Fig. 1 und 2 sowie auch in den nachfolgenden Figuren werden jene Bestandteile, die denen der Fig. 15 entsprechen, mit denselben Bezugszeichen bezeichnet, zu welchen jedoch noch 10 hinzugezählt wurde. Das in Fig. 1 und 2 gezeigte Ausführungsbeispiel unterscheidet sich von dem in Fig. 15 gezeigten herkömmlichen Wandler dahingehend, daß das Schwinggehäuse 11 der Fig. 1 und 2 aus einem porösen Kunststoff gebildet ist.1 and 2 form an embodiment of the ultrasonic transducer according to the invention. In FIGS. 1 and 2 and also in the subsequent figures, those components which correspond to those in FIG. 15 are designated with the same reference numerals, to which, however, 10 has been added. The exemplary embodiment shown in FIGS. 1 and 2 differs from the conventional converter shown in FIG. 15 in that the oscillating housing 11 of FIGS. 1 and 2 is formed from a porous plastic.

Ein piezoelektrisches Element 12 mit Elektroden 12a und 12b ist zur Bildung eines integrierten Bauteils an die Innenfläche einer Oberplatte 11a des Gehäuseteils 11 geklebt. Das Gehäuseteil 11 weist eine zylindrische Seitenplatte 11b auf, welche einstückig mit der Oberplatte 11a verbunden ist. Der offene Endabschnitt des Gehäuseteils 11 ist mit einer Abdeckplatte 13 versehen, an welcher ein Paar Anschlußstifte 14a und 14b angebracht sind. Leitungsdrähte 15a und 15b erstrecken sich zwischen der Elektrode 12a und dem Anschlußstift 14a bzw. zwischen der Elektrode 12b und dem Anschlußstift 14b. Die Abdeckplatte 13 ist mit einer Isolierschicht 16 überdeckt. Mit 17 ist ein Isolator bezeichnet, der dann vorgesehen ist, wenn die Abdeckplatte aus einem elektrischen Leiter gebildet ist, um für die Isolierung zwischen den beiden Anschlußstiften 14a und 14b zu sorgen.A piezoelectric element 12 with electrodes 12a and 12b is bonded to the inner surface of an upper plate 11a of the housing part 11 to form an integrated component. The housing part 11 has a cylindrical side plate 11b which is integrally connected to the top plate 11a. The open end portion of the housing part 11 is provided with a cover plate 13 to which a pair of terminal pins 14a and 14b are attached. Lead wires 15a and 15b extend between electrode 12a and pin 14a and between electrode 12b and pin 14b, respectively. The cover plate 13 is covered with an insulating layer 16. Denoted at 17 is an insulator which is provided when the cover plate is formed from an electrical conductor in order to provide the insulation between the two connection pins 14a and 14b.

Bei dem in Fig. 1 und 2 gezeigten Ausführungsbeispiel sind sowohl die Oberplatte 11a als auch die Seitenplatte 11b aus porösem Kunststoff gebildet. Der Begriff "poröser Kunststoff", der hier verwendet wird,-soll ein synthetisches Polymermaterial umfassen, das eine große Anzahl geschlossener Zellen aufweist, die innerhalb des Polymermaterials verteilt sind. Beispielhaft für geeignete poröse Kunststoffe sind synthetische Polymermaterialien, in welchen eine große Anzahl von Glas-Mikroballons verteilt ist, sowie aufgeschäumte, synthetische Polymermaterialien, die unter Verwendung von Aufschäummitteln in herkömmlicher Weise hergestellt sind. Bevorzugt hat der poröse Kunststoff einen mittleren Porendurchmesser, der zwischen 50 und 100 µ liegt. Beispielhaft für geeignete Polymermaterialien sind Epoxidharze, Polyolefinharze, Styrolharze, Acrylharze und Vinylchloridharze.In the embodiment shown in FIGS. 1 and 2, both the top plate 11a and the side plate 11b are formed from porous plastic. The term "porous plastic" as used herein is intended to include a synthetic polymeric material that has a large number of closed cells distributed within the polymeric material. Examples of suitable porous plastics are synthetic polymer materials in which a large number of glass microballoons are distributed, and foamed synthetic polymer materials materials which are produced using foaming agents in a conventional manner. The porous plastic preferably has an average pore diameter which is between 50 and 100 μ. Examples of suitable polymer materials are epoxy resins, polyolefin resins, styrene resins, acrylic resins and vinyl chloride resins.

Weil das Schwinggehäuseteil 11 der vorliegenden Erfindung aus porösem Kunststoff geformt ist, ist das Qm des eine Welle sendenden und empfangenden Abschnitts des Ultraschallwandlers dieser Erfindung niedrig, so daß die Impuls-Anstiegs-und -Abfallzeit verkürzt werden kann, wie in Fig. 16b dargestellt ist. Die Verringerung der ImpulsAbfallzeit führt vorteilhafterweise zur Verringerung der Nachhallzeit. Da außerdem die Oberplatte 11a eine verhältnismäßig große Luftmenge enthält, nähert sich die akkustische Impedanz der Oberplatte 11a jener von Luft. Deshalb sind die Anpaßbedingungen zwischen der Oberplatte 11a und der Umgebungsluft verbessert, was zu einer Verbesserung beim Ansprechverhalten führt,das heißt, es ist ein intensiverer Ausgang nach dem Empfang einer Ultraschallwelle gleichbleibender Intensität erzielbar.Because the vibrating case 11 of the present invention is molded from porous plastic, the Q m of the wave transmitting and receiving portion of the ultrasonic transducer of this invention is low, so that the pulse rise and fall times can be shortened as shown in Fig. 16b is. The reduction in the pulse decay time advantageously leads to a reduction in the reverberation time. In addition, since the top plate 11a contains a relatively large amount of air, the acoustic impedance of the top plate 11a approaches that of air. Therefore, the fitting conditions between the top plate 11a and the ambient air are improved, which leads to an improvement in response, that is, a more intense output can be obtained after receiving an ultrasonic wave of constant intensity.

Es liefert beispielsweise der herkömmliche Ultraschallwandler, dessen Gehäuse aus rostfreiem Stahl gebildet ist, eine Impulsanstiegszeit von 0,5 ms, eine Impulsabfallzeit von 2,0 ms und eine Ausgangsspannung von 0,4 V. Ein Ultraschallwandler, dessen Schwinggehäuse aus nicht porösem Epoxidharz gebildet ist, liefert eine Impulsanstiegszeit von 0,2 ma, eine Impulsabfallzeit von 1,2 ms und eine Ausgangsspannung von 2,6 V. Im Fall eines er- findungsgemäßen Ultraschallwandlers, bei welchem das Schwinggehäuse aus einem Epoxidharz gebildet ist, in welchem eine große Anzahl von Glas-Mikroballons verteilt ist, die einen Durchmesser von 50 bis 100 µ aufweisen, ergibt sich eine Impulsanstiega- und -abfallzeit von 0,2 bzw. 1,2 ms, und die Ausgangsspannung beträgt 6,4 V.It provides, for example, the conventional ultrasonic transducer, whose housing is made of stainless steel, a pulse rise time of 0.5 ms, a pulse fall time of 2.0 ms and an output voltage of 0.4 V. An ultrasonic transducer, the oscillating housing of which is made of non-porous epoxy resin provides a pulse rise time of 0.2 mA, a pulse fall time of 1.2 ms and an output voltage of 2.6 V. in the case of an experienced findungsgemä ß en ultrasonic transducer, wherein the oscillating body is formed of an epoxy resin, in which a large Distributed number of glass microballoons that have a diameter of 50 to 100 microns, there is a pulse rise and fall time of 0.2 or 1.2 ms, and the output voltage is 6.4 V.

Vorzugsweise beträgt die Dicke der Oberplatte 11 a des Schwinggehäuses 11 etwa 1/4 der Wellenlänge der Schallgeschwindigkeit der Oberplatte 11a, und zwar aus dem Grunde, ein bestes Ansprechverhalten zu erreichen.Preferably, the thickness of the top plate 11 a of the vibrating housing 11 is about 1/4 of the wavelength of the speed of sound of the top plate 11 a, for the reason of achieving the best response.

Bei dem obigen Ausführungsbeispiel sind sowohl die Oberplatte 11a als auch die zylindrische Seitenplatte 11b aus pörosem Kunststoff geformt. Eine ähnliche Verbesserung kann selbst dann erhalten werden, wenn die Oberplatte alleine aus einem porösen Kunststoff geformt ist. Es wird nun auf Fig. 3 Bezug genommen; eine zylindrische Seitenplatte 11b ist an ihrem einen Ende einstückig mit einer Oberplatte 11a versehen, die aus porösem Kunststoff der gerade voranstehend erwähnten Art geformt ist., Die anderen Bauweisen des Wandlers sind im wesentlichen dieselben wie beim Ausführungsbeispiel der Fig. 1 und 2, und deren detaillierte Erläuterung wird hier weggelassen. Die Fig. 4 und 5 bilden Ausführungsbeispiele ähnlich jenem der Fig. 3 ab. In Fig. 4 steht der Außenumfang der Oberplatte 11a in Berührung mit der Innenfläche der zylindrischen Seitenplatte 11b. In Fig. 5 sind der Endabschnitt der Oberplatte 11a und die Seitenplatte 11b diagonal zum Anschlageingriff miteinander geschnitten. Die Befestigung der Oberplatte 11a an der Seitenplatte 11b kann durch irgendwelche bekannten Mittel vorgenommen werden, etwa durch Kleber.In the above embodiment, both the top plate 11a and the cylindrical side plate 11b are molded from solid plastic. A similar improvement can be obtained even if the top plate is molded from a porous plastic alone. Referring now to Fig. 3; a cylindrical side plate 11b is integrally provided at one end with a top plate 11a molded from porous plastic of the type just mentioned. The other designs of the transducer are substantially the same as in the embodiment of Figs. 1 and 2, and their detailed explanation is omitted here. 4 and 5 depict exemplary embodiments similar to that of FIG. 3. In Fig. 4, the outer periphery of the top plate 11a is in contact with the inner surface of the cylindrical side plate 11b. In Fig. 5, the end portion of the top plate 11a and the side plate 11b are cut together diagonally for abutment engagement. The top plate 11a can be attached to the side plate 11b by any known means, such as glue.

Bei den in den Fig. 3 bis 5 gezeigten Ausführungsbeispielen ist vorzugsweise die zylindrische Seitenplatte 11b aus einem Material geformt, dessen akkustische Impedanz größer ist.als jene der Oberplatte 11a, und zwar aus dem Grunde, eine Verringerung der Nachhallzeit zu erreichen. Beispielhaft für ein geeignetes Material für die Seitenplatte 11b sind Kunststoffe, Metalle und keramische Stoffe. Wenn sowohl die Oberplatte als auch die Seitenplatte des Schwinggehäuses aus einem porösen Kunststoff geformt sind, dann ist die Schwingung an der Seite des Schwinggehäuses 11 nicht vollständig gedämpft, und die Nachhallzeit kann nicht unter eine bestimmte Grenze abgesenkt werden. Wenn im Gegensatz hierzu die Seitenplatte 11b aus einem Material geformt ist, dessen akkustische Impedanz größer ist als jene der Oberplatte 11a, welche aus einem porösen Kunststoff gebildet ist, dann wird die Schwingung der Oberplatte 11a an der Trennfläche zwischen der Oberplatte 11a und der Seitenplatte 11b reflektiert und verteilt und ist daran gehindert, zur Seitenplatte 11b fortzuschreiten. Demzufolge wird die Nachhallzeit kürzer,verglichen mit dem Wandler, bei welchem das Schwinggehäuse vollständig aus porösem Kunststoff geformt ist.In the embodiments shown in Figs. 3-5, the cylindrical side plate 11b is preferably molded from a material whose acoustic impedance is greater than that of the top plate 11a, for the purpose of achieving a reduction in reverberation time. Examples of a suitable material for the side plate 11b are plastics, metals and ceramic materials. If both the top plate and the side plate of the vibrating housing are molded from a porous plastic, then the vibration on the side of the vibrating housing 11 is not completely damped, and the reverberation time cannot be reduced below a certain limit. In contrast, when the side plate 11b is molded from a material whose acoustic impedance is larger than that of the top plate 11a made of a porous plastic, the vibration of the top plate 11a at the interface between the top plate 11a and the side plate 11b reflects and distributes and is prevented from proceeding to the side plate 11b. As a result, the reverberation time becomes shorter compared to the transducer in which the vibrating housing is completely molded from porous plastic.

Es zeigt beispielsweise der Ultraschallwandler, dessen Schwinggehäuse aus porösem Kunststoff mit einer akkustischen Impedanz von 1 x 3000 g/cmzs geformt ist, eine Wellen sendende Impulscharakteristik, wie sie durch die Linie 20 in Fig. 6 gezeigt ist. Wenn andererseits das Schwinggehäuse aus einer zylindrischen Seitenplatte gebildet ist, welche aus rostfreiem Stahl mit einer akkustischen Impedanz von 7,8 x 5000 g/cm2s geformt ist, sowie einer Oberplatte, die aus einem porösen Kunststoff mit 1 x 3000 g/cmzs an akustischer Impedanz geformt ist, dann liefert der Wandler die Impulscharakteristik, wie sie durch die gestrichelte Linie 21 in Fig. 6 gezeigt ist. Das heißt, die Nachhallzeit kann bis auf unter 1,0 ms abgesenkt werden.For example, the ultrasonic transducer, whose oscillating housing is formed from porous plastic with an acoustic impedance of 1 x 3000 g / cm z s, shows a wave-transmitting pulse characteristic as shown by line 20 in FIG. 6. On the other hand, if the vibrating housing is formed from a cylindrical side plate, which is formed from stainless steel with an acoustic impedance of 7.8 x 5000 g / cm 2 s, and an upper plate, which is made of a porous plastic with 1 x 3000 g / cm z s is shaped on acoustic impedance, then the transducer provides the pulse characteristic as shown by the broken line 21 in FIG. 6. This means that the reverberation time can be reduced to less than 1.0 ms.

Eine'solche Verringerung der Nachhallzeit (oder ImpulsAbfallzeit) kann auch dadurch bewirkt werden, daß man ein integriertes rohrförmiges Teil oder Teile an dem Außen-und/oder Innenumfang der zylindrischen Seitenplatte des Wandlers vorsieht, der in Fig. 1 und 2 gezeigt ist, wobei das rohrförmige Teil eine höhere akkustische Impedanz aufweist als die zylindrische Seitenplatte. Es wird nun auf Fig. 7 Bezug genommen: ein rohrförmiges Teil 18 ist innerhalb eines Schwinggehäuses vorgesehen und mit dem Innenumfang seiner zylindrischen Seitenplatte 11b verklebt. In einer Alternativausführung, die in Fig. 8 gezeigt ist, ist das rohrförmige Teil 18 am Außenumfang der Seitenplatte 11b angeklebt. Durch die Anordnung des rohrför- migen Teils 18 wire eieschwingungsdämpfende Wirkung an der Seite des Schwinggehäuses verbessert, um die Nachhallzeit zu verringern. Die Befestigung des rohrförmigen Teils 18 an der Seitenplatte 11b kann durch irgendwelche bekannten Mittel, etwa durch Kleber, bewirkt werden. Wenn das rohrförmige Teil 1 innerhalb des Gehäuses 11 vorgesehen ist, dann ist es zweckmäßig, das rohrförmige Teil als elastisches Rohr auszubilden, und zwar allgemein ein Metallrohr, welches einen Schlitz 18a aufweist, der sich parallel zur Achse des Rohres erstreckt. Das Rohr 18 weist einen größeren Außendurchmesser als den Innendurchmesser der Seitenplatte 11b in freiem Zustand auf. Durch Einsetzen des Rohrs 18 in das Innere des Gehäuses steht das Rohr 18 in Druckberührung mit der Innenfläche der zylindrischen Seitenplatte 11b. Wenn in ähnlicher Weise das rohrförmige Teil 18 außerhalb des Gehäuses 11 vorgesehen ist, ist es möglich, ein elastisches Rohr, wie etwa ein Gummirohr, zu benutzen, das einen kleineren Innendurchmesser als der Außendurchmesser der zylindrischen Seitenplatte 11b aufweist. Durch passendes Aufsetzen des Gummirohrs 18 rund um den Umfang der Seitenplatte 11b wird das Rohr in Druckberührung mit der Seitenplatte 11b gehalten. Wenn das elastische rohrförmige Teil verwendet wird, ist es für das rohrförmige Teil nicht erforderlich, aus einem Material mit einer größeren akkustischen Impedanz als der Seitenplatte 11b gebildet zu werden, und zwar wegen des Umstandes, daß die Seitenplatte 11b stets den. Kräften in der Richtung senkrecht zur Achse der zylindri-. schen Seitenplatte 11b ausgesetzt ist und an der Schwingung gehindert ist.Such a reduction in reverberation time (or pulse decay time) can also be accomplished by providing an integrated tubular part or parts on the outer and / or inner circumference of the cylindrical side plate of the transducer shown in Figs. 1 and 2, wherein the tubular part has a higher acoustic impedance than the cylindrical side plate. Referring now to Figure 7, a tubular member 18 is provided within a swing housing and bonded to the inner periphery of its cylindrical side plate 11b. In an alternative embodiment, shown in Fig. 8 the tubular member 18 is adhered to the outer periphery of the side plate 11b. The arrangement of the rohrför- m e n ig portion 18 improves wire eieschwingungsdämpfende effect on the side of the oscillating body, in order to reduce the reverberation time. Attachment of tubular member 18 to side plate 11b can be accomplished by any known means, such as glue. If the tubular part 1 is provided within the housing 11, then it is expedient to design the tubular part as an elastic tube, generally a metal tube which has a slot 18a which extends parallel to the axis of the tube. The tube 18 has a larger outer diameter than the inner diameter of the side plate 11b in the free state. By inserting the tube 18 into the inside of the housing, the tube 18 is in pressure contact with the inner surface of the cylindrical side plate 11b. Similarly, if the tubular member 18 is provided outside the housing 11, it is possible to use an elastic tube, such as a rubber tube, which has a smaller inner diameter than the outer diameter of the cylindrical side plate 11b. By fitting the rubber tube 18 around the circumference of the side plate 11b, the tube is held in pressure contact with the side plate 11b. When the elastic tubular member is used, it is not necessary for the tubular member to be made of a material having a greater acoustic impedance than the side plate 11b because of the fact that the side plate 11b is always the same. Forces in the direction perpendicular to the axis of the cylindrical. The side plate 11b is exposed and is prevented from vibrating.

Die Fig. 10 bis 13 bilden Verbesserungen der Ultraschallwandler der vorangehenden Ausführungsbeispiele ab, wobei die Dicke der Oberplatte 11a plötzlich an einem Ringabschnitt nahe dem Außenumfang der piezoelektrischen Scheibe 12 geändert ist, um die Querschwingung, die vom Umfang keilförmig) ausgebildet sein. Vorzugsweise sind die Höhe des erhabenen Abschnitts 11c und die Tiefe der Ringnut 11d nicht größer als 1/3 der Dicke D der Oberplatte 11a, um eine Verringerung im Ansprechverhalten zu verhindern.10 to 13 illustrate improvements in the ultrasonic transducers of the foregoing embodiments, wherein the thickness of the top plate 11a is suddenly changed at a ring portion near the outer periphery of the piezoelectric disk 12 by the transverse vibration that is circumferential be wedge-shaped). Preferably, the height of the raised portion 11c and the depth of the annular groove 11d are not larger than 1/3 of the thickness D of the top plate 11a to prevent a decrease in responsiveness.

Claims (9)

1. Ultraschallwandler mit den folgenden Merkmalen: - ein Schwinggehäuseteil (11) mit einer zylindrischen Seitenplatte (11b) und einer Wellen sendenden und empfangenden Oberplatte (11a), welche am einen Ende der Seitenplatte vorgesehen ist, - ein piezoelektrisches Element (12), welches einstückig mit der Innenwand der Oberplatte (11a) verbunden ist, und - Elektroden (12a, 12b), die am piezoelektrischen Element (12) derart angeordnet sind, daß Ultraschallwellen von der Oberplatte (11a) erzeugt werden können, wenn ein elektrisches Feld an die Elektroden angelegt wird und/oder ein elektrischer Ausgang von den Elektroden abgegeben wird, wenn die Oberplatte Ultraschallwellen empfängt,
dadurch gekennzeichnet, daß die Oberplatte (11a) aus porösem Kunststoff geformt ist. 1. Ultrasonic transducer with the following features: a vibrating housing part (11) with a cylindrical side plate (11b) and a shaft-transmitting and receiving top plate (11a), which is provided at one end of the side plate, - A piezoelectric element (12) which is integrally connected to the inner wall of the top plate (11a), and - Electrodes (12a, 12b) which are arranged on the piezoelectric element (12) in such a way that ultrasonic waves can be generated by the top plate (11a) when an electric field is applied to the electrodes and / or an electrical output is emitted from the electrodes when the top plate receives ultrasonic waves,
characterized in that the top plate (11a) is molded from porous plastic. 2. Ultraschallwandler nach Anspruch 1, dadurch gekennzeichnet, daß die zylindrische Seitenplatte (11b) aus einem Material geformt ist, dessen akkustische Impedanz größer ist als jene der Oberplatte (11a).2. Ultrasonic transducer according to claim 1, characterized in that the cylindrical side plate (11b) is formed from a material whose acoustic impedance is greater than that of the top plate (11a). 3. Ultraschallwandler nach Anspruch 1, dadurch gekennzeichnet, daß die zylindrische Seitenplatte (11b) ebenfalls aus einem porösen Kunststoff geformt ist.3. Ultrasonic transducer according to claim 1, characterized in that the cylindrical side plate (11b) is also formed from a porous plastic. 4. Ultraschallwandler nach Anspruch 3, ferner gekennzeichnet durch ein rohrförmiges Teil (18), das aus einem Material geformt ist, dessen akkustische Inpedanz größer ist als jene der zylindrischen Seitenplatte (11b), und an mindestens einer von Innen- und Außenumfangsfläche der zylindrischen Seitenwand zum Verringern der Nachhallzeit vorgesehen ist.4. The ultrasonic transducer of claim 3, further characterized by a tubular member (18) molded from a material whose acoustic impedance is greater than that of the cylindrical side plate (11b) and on at least one of the inner and outer peripheral surfaces of the cylindrical side wall is provided to reduce the reverberation time. 5. Ultraschallwandler nach Anspruch 4, dadurch gekennzeichnet, daß das rohrförmige Teil (18) ein elastisches Rohr ist, dessen Innendurchmesser kleiner ist als der Außendurchmesser der zylindrischen Seitenplatte (11b) und welches außerhalb der zylindrischen Seitenplatte zur Druckberührung hiermit vorgesehen ist.5. Ultrasonic transducer according to claim 4, characterized in that the tubular part (18) is an elastic tube, the inner diameter of which is smaller than the outer diameter of the cylindrical side plate (11b) and which is provided outside the cylindrical side plate for pressure contact therewith. 6. Ultraschallwandler nach Anspruch 4, dadurch gekennzeichnet, daß das rohrförmige Teil (18) ein Metallrohr ist, welches mit einem Schlitz (18a) in einer Richtung parallel zur Achse hiervon versehen ist, welches einen Außendurchmesser aufweist, der größer ist als ein Innendurchmesser der zylindrischen Seitenplatte (11b) und welches innerhalb der Seitenplatte zur Druckberührung hiermit vorgesehen ist.6. Ultrasonic transducer according to claim 4, characterized in that the tubular part (18) is a metal tube which is provided with a slot (18a) in a direction parallel to the axis thereof, which has an outer diameter which is larger than an inner diameter of the cylindrical side plate (11b) and which is provided within the side plate for pressure contact therewith. 7. Ultraschallwandler nach irgendeinem der vorangehenden Ansprüche, dadurch gekennzeichnet, daß das piezoelektrische Element die Form einer scheibenförmigen Platte (12) und konzentrisch an der Oberplatte (11a) angeordnet ist, und daß die Oberplatte (11a) einen ringförmigen Abschnitt aufweist, der neben und längs dem Außenumfang des piezoelektrischen Elements angeordnet ist und an welchem die Dicke der Oberplatte plötzlich derart geändert ist , daß die Querschwingung, die vom Umfang des piezoelektrischen Elements ausgeht, am ringförmigen Abschnitt absorbiert oder abgemildert werden kann.7. Ultrasonic transducer according to any one of the preceding claims, characterized in that the piezoelectric element is arranged in the form of a disk-shaped plate (12) and concentrically on the top plate (11a), and in that the top plate (11a) has an annular section which is arranged next to and along the outer circumference of the piezoelectric element and on which the thickness of the top plate is suddenly changed such that the transverse vibration originating from the circumference of the piezoelectric element can be absorbed or reduced at the annular section. 8. Ultraschallwandler nach Anspruch 7, dadurch gekennzeichnet, daß der ringförmige Abschnitt ein Grenzbereich eines erhabenen Abschnitts (11c) ist, der von Außen-und Innenfläche der Oberplatte (11a) an mindestens einer vorgesehen ist.8. Ultrasonic transducer according to claim 7, characterized in that the annular section is a boundary region of a raised section (11c), which is provided on the outer and inner surface of the top plate (11a) on at least one. 9. Ultraschallwandler nach Anspruch 7, dadurch gekennzeichnet, daß der ringförmige Abschnitt eine Ringnut ist, die von Außen- und Innenoberfläche der Oberplatte (11a) an mindestens einer vorgesehen ist.9. Ultrasonic transducer according to claim 7, characterized in that the annular section is an annular groove which is provided on at least one of the outer and inner surface of the top plate (11 a).
EP84112594A 1984-02-21 1984-10-18 Ultrasonic transducer Expired - Lifetime EP0178346B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE8484112594T DE3486035D1 (en) 1984-10-18 1984-10-18 ULTRASONIC transducer.

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2434684U JPS60136599U (en) 1984-02-21 1984-02-21 Ultrasonic ceramic sensor
JP2648784U JPS60139399U (en) 1984-02-24 1984-02-24 Ultrasonic ceramic sensor
JP5034784U JPS60163899U (en) 1984-04-06 1984-04-06 Ultrasonic ceramic sensor

Publications (2)

Publication Number Publication Date
EP0178346A1 true EP0178346A1 (en) 1986-04-23
EP0178346B1 EP0178346B1 (en) 1993-01-13

Family

ID=27284612

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84112594A Expired - Lifetime EP0178346B1 (en) 1984-02-21 1984-10-18 Ultrasonic transducer

Country Status (5)

Country Link
US (1) US4556814A (en)
EP (1) EP0178346B1 (en)
DE (1) DE3505872C2 (en)
DK (1) DK168317B1 (en)
FR (1) FR2559985B1 (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0361757A2 (en) * 1988-09-29 1990-04-04 British Gas plc A matching member
US4914959A (en) * 1987-04-24 1990-04-10 Den Norske Stats Oljeselskap A.S. Ultrasonic flow meter using obliquely directed transducers
US4945276A (en) * 1987-04-24 1990-07-31 Den Norske Stats Oljeselskap A.S. Transducer for arranging in a fluid, particularly for the measurement of the flow-velocity of a fluid in a pipe, by transmitting/receiving sonic pulses
WO1995007529A1 (en) * 1993-09-10 1995-03-16 Siemens Aktiengesellschaft Ultrasonic transducer with adapter
DE19512417A1 (en) * 1995-04-03 1996-10-10 Marco Systemanalyse Entw Piezoelectric ultrasonic transducer
WO1997026646A1 (en) * 1996-01-18 1997-07-24 Itt Automotive Europe Gmbh Damped ultrasonic transducer
WO1998004361A1 (en) * 1996-07-26 1998-02-05 Siemens Aktiengesellschaft Ultrasonic transducer with a disk-shaped quarter wave length transformer
WO2017005686A1 (en) * 2015-07-07 2017-01-12 Valeo Schalter Und Sensoren Gmbh Ultrasonic sensor for a motor vehicle, motor vehicle, and method for producing an ultrasonic sensor

Families Citing this family (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3545381C2 (en) * 1985-12-20 1994-02-24 Siemens Ag Ultrasonic transducer for measuring the sound power of a focused ultrasonic field
JPH0749914Y2 (en) * 1986-01-29 1995-11-13 株式会社村田製作所 Ultrasonic transducer
US4770038A (en) * 1986-02-13 1988-09-13 The United States Of America As Represented By The Administrator Of National Aeronautics And Space Administration Ultrasonic depth gauge for liquids under high pressure
JPH057835Y2 (en) * 1986-06-10 1993-02-26
US4783997A (en) * 1987-02-26 1988-11-15 Panametrics, Inc. Ultrasonic transducers for high temperature applications
DE8805953U1 (en) * 1988-05-05 1988-07-07 Hoentzsch Gmbh, 7050 Waiblingen, De
DE4120681A1 (en) * 1990-08-04 1992-02-06 Bosch Gmbh Robert ULTRASONIC CONVERTER
DE4028315A1 (en) * 1990-09-06 1992-03-12 Siemens Ag ULTRASONIC CONVERTER FOR THE RUN TIME MEASUREMENT OF ULTRASONIC IMPULSES IN A GAS
US5121628A (en) * 1990-10-09 1992-06-16 Merkl Arthur W Ultrasonic detection system
US5285789A (en) * 1992-04-21 1994-02-15 Hewlett-Packard Company Ultrasonic transducer apodization using acoustic blocking layer
DE29611678U1 (en) * 1996-07-04 1997-08-07 Siemens Ag Sound transducers, in particular ultrasound transducers
JPH10294995A (en) * 1997-04-21 1998-11-04 Matsushita Electric Ind Co Ltd Dripproof ultrasonic wave transmitter
JP3596364B2 (en) * 1999-08-05 2004-12-02 松下電器産業株式会社 Ultrasonic transducer and ultrasonic flow measurement device
JP3501100B2 (en) * 2000-05-15 2004-02-23 株式会社村田製作所 Ultrasonic transducer
JP3768789B2 (en) * 2000-09-07 2006-04-19 アルプス電気株式会社 Ultrasonic vibrator, wet processing nozzle and wet processing apparatus
DE10156259A1 (en) 2001-11-09 2003-05-22 Valeo Schalter & Sensoren Gmbh Ultrasonic sensor and method for manufacturing an ultrasonic sensor
JP3944052B2 (en) * 2001-12-27 2007-07-11 株式会社デンソー Ultrasonic transducer and ultrasonic clearance sonar using the same
JP3633926B2 (en) * 2002-01-28 2005-03-30 松下電器産業株式会社 Ultrasonic transceiver and ultrasonic flowmeter
JP4007128B2 (en) * 2002-03-22 2007-11-14 株式会社豊田中央研究所 Pressure sensor and sensor unit
US6788620B2 (en) * 2002-05-15 2004-09-07 Matsushita Electric Ind Co Ltd Acoustic matching member, ultrasound transducer, ultrasonic flowmeter and method for manufacturing the same
JP4048886B2 (en) * 2002-09-10 2008-02-20 株式会社村田製作所 Ultrasonic sensor
CN100566152C (en) * 2002-09-12 2009-12-02 Nxp股份有限公司 Has the bulk acoustic wave resonator that suppresses the device of passband ripple in the bulk accoustic wave filter
US7513147B2 (en) 2003-07-03 2009-04-07 Pathfinder Energy Services, Inc. Piezocomposite transducer for a downhole measurement tool
US7075215B2 (en) * 2003-07-03 2006-07-11 Pathfinder Energy Services, Inc. Matching layer assembly for a downhole acoustic sensor
JP4503347B2 (en) * 2004-04-28 2010-07-14 日本電波工業株式会社 Manufacturing method of ultrasonic probe
DE102005001899B4 (en) * 2005-01-14 2007-03-08 Landis+Gyr Gmbh ultrasound probe
JP2006203563A (en) * 2005-01-20 2006-08-03 Nippon Soken Inc Ultrasonic sensor
US20060291677A1 (en) * 2005-06-09 2006-12-28 Airdigit Incorporation High-fidelity piezoelectric contact-type microphone structure
US7307373B2 (en) * 2005-08-12 2007-12-11 Daniel Measurement And Control, Inc. Transducer assembly for an ultrasonic fluid meter
RU2450247C2 (en) * 2005-08-12 2012-05-10 Дэниел Мэжэмэнт энд Кэнтроул, Инк. Ultrasonic flow metre, transducer unit for said flow metre and method of replacing transducers
JP4407767B2 (en) * 2006-02-14 2010-02-03 株式会社村田製作所 Ultrasonic sensor and manufacturing method thereof
DE102006028211A1 (en) * 2006-06-14 2007-12-20 Valeo Schalter Und Sensoren Gmbh Ultrasonic sensor with membrane
CN101529927B (en) * 2006-10-20 2012-09-26 株式会社村田制作所 Ultrasonic sensor
DE102008003283A1 (en) * 2008-01-05 2009-07-09 Marquardt Gmbh Sensor i.e. level sensor, for detecting maximum level in domestic appliance i.e. wet and/or dry vacuum cleaner, has adjustment element formed as part of housing to adjust impedance of vibration producing element to impedance of medium
DK2263808T3 (en) * 2009-06-19 2014-06-10 Sonovia Holdings Llc Dual-Frequency ultrasonic transducer
EP2530953B1 (en) 2010-01-25 2018-03-14 Murata Manufacturing Co., Ltd. Ultrasonic vibration device
US20130099791A1 (en) * 2011-10-24 2013-04-25 Baker Hughes Incorporated Methodologies to Improve Reliability of Transducer Electrical Interconnections
DE102012104109A1 (en) 2012-05-10 2013-11-14 Manroland Web Systems Gmbh Printing machine cylinder e.g. transfer cylinder, for printing element, has coating comprising plastic layer attached on mantle surface of metallic cylinder base body and metallic or ceramic material layer attached on plastic layer
DE102012211011A1 (en) * 2012-06-27 2014-01-02 Robert Bosch Gmbh Acoustic sensor with a membrane made of a fiber composite material
DE102012222239A1 (en) * 2012-12-04 2014-06-05 iNDTact GmbH Measuring device and component with integrated measuring device
US20150090030A1 (en) * 2013-09-27 2015-04-02 Infineon Technologies Ag Transducer arrangement comprising a transducer die and method of covering a transducer die
US10935646B2 (en) 2014-02-27 2021-03-02 Simtrans Tech Inc Ultrasonic transducer with composite case
KR20170033865A (en) * 2014-07-22 2017-03-27 브레우어 사이언스 인코포레이션 Thin-film resistive-based sensor
DE102016107471B3 (en) * 2016-04-22 2017-09-14 Krohne Ag Ultrasonic transducer with radiating element
US11590535B2 (en) 2017-10-25 2023-02-28 Honeywell International Inc. Ultrasonic transducer
DE102017221618A1 (en) * 2017-10-27 2019-05-02 Continental Automotive Gmbh Ultrasonic transducer with at least one piezoelectric oscillator
DE102018106333A1 (en) * 2018-03-19 2019-09-19 HELLA GmbH & Co. KGaA Sensor device for detecting sound, in particular for detecting structure-borne noise on a vehicle
GB2573305A (en) * 2018-05-01 2019-11-06 Tribosonics Ltd An ultrasonic transducer
CN110882882A (en) * 2018-09-07 2020-03-17 新传思科技股份有限公司 Ultrasonic transducer with composite material shell

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR896806A (en) * 1940-02-22 1945-03-05 Atlas Werke Ag Piezoelectric oscillator device
US3433461A (en) * 1967-05-22 1969-03-18 Edison Instr Inc High-frequency ultrasonic generators
US3555311A (en) * 1969-01-23 1971-01-12 Marquardt Corp High pressure piezoelectric transducer
FR2325266A1 (en) * 1975-09-17 1977-04-15 Siemens Ag ULTRASONIC TRANSDUCER
EP0116823A1 (en) * 1983-01-20 1984-08-29 Siemens Aktiengesellschaft Ultrasonic transducer

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB778168A (en) * 1954-07-02 1957-07-03 Babcock & Wilcox Ltd Improvements relating to probe supporting means for ultrasonic testing of butt weldsformed between sections of hollow cylindrical bodies such as pipes and to an improved method of testing butt welds formed between such sections
US3209582A (en) * 1961-05-31 1965-10-05 Elmer H Greenberg Apparatus for scanning large objects with a test-unit probe
FR2172808B1 (en) * 1972-02-22 1978-09-29 Inst Francais Du Petrole
US3928777A (en) * 1974-08-26 1975-12-23 Dellorfano Jr Fred M Directional ultrasonic transducer with reduced secondary lobes
US3946599A (en) * 1974-11-08 1976-03-30 Jacob Patt Liquid applicator for ultra-sonic transducer
US4373401A (en) * 1980-05-05 1983-02-15 Joseph Baumoel Transducer structure and mounting arrangement for transducer structure for clamp-on ultrasonic flowmeters

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR896806A (en) * 1940-02-22 1945-03-05 Atlas Werke Ag Piezoelectric oscillator device
US3433461A (en) * 1967-05-22 1969-03-18 Edison Instr Inc High-frequency ultrasonic generators
US3555311A (en) * 1969-01-23 1971-01-12 Marquardt Corp High pressure piezoelectric transducer
FR2325266A1 (en) * 1975-09-17 1977-04-15 Siemens Ag ULTRASONIC TRANSDUCER
EP0116823A1 (en) * 1983-01-20 1984-08-29 Siemens Aktiengesellschaft Ultrasonic transducer

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4914959A (en) * 1987-04-24 1990-04-10 Den Norske Stats Oljeselskap A.S. Ultrasonic flow meter using obliquely directed transducers
US4945276A (en) * 1987-04-24 1990-07-31 Den Norske Stats Oljeselskap A.S. Transducer for arranging in a fluid, particularly for the measurement of the flow-velocity of a fluid in a pipe, by transmitting/receiving sonic pulses
EP0361757A2 (en) * 1988-09-29 1990-04-04 British Gas plc A matching member
EP0361757A3 (en) * 1988-09-29 1991-09-25 British Gas plc A matching member
GB2225426B (en) * 1988-09-29 1993-05-26 Michael John Gill A transducer
WO1995007529A1 (en) * 1993-09-10 1995-03-16 Siemens Aktiengesellschaft Ultrasonic transducer with adapter
DE19512417A1 (en) * 1995-04-03 1996-10-10 Marco Systemanalyse Entw Piezoelectric ultrasonic transducer
WO1997026646A1 (en) * 1996-01-18 1997-07-24 Itt Automotive Europe Gmbh Damped ultrasonic transducer
WO1998004361A1 (en) * 1996-07-26 1998-02-05 Siemens Aktiengesellschaft Ultrasonic transducer with a disk-shaped quarter wave length transformer
US6104121A (en) * 1996-07-26 2000-08-15 Siemens Ag Ultrasonic transducer with a disk-shaped quarter wave length transformer
WO2017005686A1 (en) * 2015-07-07 2017-01-12 Valeo Schalter Und Sensoren Gmbh Ultrasonic sensor for a motor vehicle, motor vehicle, and method for producing an ultrasonic sensor

Also Published As

Publication number Publication date
FR2559985B1 (en) 1989-06-30
DK76485D0 (en) 1985-02-19
US4556814A (en) 1985-12-03
DK76485A (en) 1985-08-22
DK168317B1 (en) 1994-03-07
DE3505872C2 (en) 1994-07-07
FR2559985A1 (en) 1985-08-23
EP0178346B1 (en) 1993-01-13
DE3505872A1 (en) 1985-11-21

Similar Documents

Publication Publication Date Title
EP0178346A1 (en) Ultrasonic transducer
DE60005382T2 (en) BROADBAND UNDERWATER SOUND CONVERTER
EP1997100B1 (en) Ultrasonic sensor
DE4117638C2 (en)
DE3211072C3 (en) Directional electret microphone
DE3526488A1 (en) ULTRASONIC CONVERTER WITH PIEZOELECTRIC COMPOSITE MATERIAL
DE7313564U (en) ACOUSTIC CONVERTER WITH A PIEZOELECTRIC DRIVER
DE19832072B4 (en) Piezoelectric electroacoustic converter
EP0166976B1 (en) Ultrasonic transducer system
DE2229239A1 (en) Electromagnetic arrangement for electroacoustic transducers and the like
EP0116823A1 (en) Ultrasonic transducer
DE2812222A1 (en) ELECTROACOUSTIC VIBRATION PLATE WITH A MOVABLE COIL
EP0154706A2 (en) Piezoelectric air-ultrasound transducer with broadband characteristics
DE2537788B2 (en) Ultrasonic transducer
EP0308899A2 (en) Ultrasonic transducer with astigmatic transmission-reception characteristics
DE3005708A1 (en) CONVERTER PLATE FOR PIEZOELECTRIC CONVERTER
DE3939387A1 (en) Ultrasonic distance warning system esp. for motor vehicles - has aperture covering membrane carrying piezo-plate to eliminate group echos
EP0590176B1 (en) Ultrasonic transducer arrangement with acoustic matching layer
EP0222276A2 (en) Ultrasonic measuring head
EP0436809A2 (en) Ultrasonic transducer using piezoelectric elements
EP1038290B1 (en) Ultrasonic transducer with a cup-shaped support
DE10123612A1 (en) Ultrasonic wave transmitter/receiver e.g. for use as distance sensor in vehicle, has piezoelectric vibration element attached to inner underside surface, and ultrasonic transmission/reception surface defined by external underside surface
DE2820236A1 (en) TUNING FORK RESONATOR WITH AN ELECTRICALLY DRIVEN TUNING FORK, WITH A SUPPORT AND WITH AT LEAST ONE CONNECTING PIN FOR THE ELECTRIC DRIVE
DE3401979C2 (en)
DE19833213C2 (en) Ultrasonic transmission arrangement

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR

17P Request for examination filed

Effective date: 19861023

17Q First examination report despatched

Effective date: 19880811

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19930113

REF Corresponds to:

Ref document number: 3486035

Country of ref document: DE

Date of ref document: 19930225

EN Fr: translation not filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19940701

APAH Appeal reference modified

Free format text: ORIGINAL CODE: EPIDOSCREFNO