EP0458426B1 - Elektrodynamischer Ultraschallwandler und Ultraschalleinrichtung - Google Patents

Elektrodynamischer Ultraschallwandler und Ultraschalleinrichtung Download PDF

Info

Publication number
EP0458426B1
EP0458426B1 EP91250095A EP91250095A EP0458426B1 EP 0458426 B1 EP0458426 B1 EP 0458426B1 EP 91250095 A EP91250095 A EP 91250095A EP 91250095 A EP91250095 A EP 91250095A EP 0458426 B1 EP0458426 B1 EP 0458426B1
Authority
EP
European Patent Office
Prior art keywords
ultrasonic transducer
transducer
electrodynamic
carrier
housing
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.)
Revoked
Application number
EP91250095A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0458426A2 (de
EP0458426A3 (en
Inventor
Alfred Dipl.-Phys. Graff
Jürgen Verhoeven
Michael Dr. rer. nat. Wächter
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.)
Vodafone GmbH
Original Assignee
Mannesmann 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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=6407099&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0458426(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Mannesmann AG filed Critical Mannesmann AG
Publication of EP0458426A2 publication Critical patent/EP0458426A2/de
Publication of EP0458426A3 publication Critical patent/EP0458426A3/de
Application granted granted Critical
Publication of EP0458426B1 publication Critical patent/EP0458426B1/de
Anticipated expiration legal-status Critical
Revoked 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
    • B06B1/04—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with electromagnetism

Definitions

  • the invention relates to an electrodynamic ultrasound transducer or an ultrasound device according to the preamble of claims 1 and 14.
  • Ultrasonic transducers or ultrasonic devices of the generic type are shown in the as yet unpublished German patent application P 40 03 215.9-52.
  • the magnet system and transducer coil are arranged with respect to one another in such a way that eddy currents are induced in the workpiece surface via the transducer coil, which is acted upon by high-frequency alternating current.
  • the thus generated movements of the electrons near the surface couple to the metal grid and thus generate density fluctuation waves, ie ultrasound.
  • the resulting ultrasound waves are given a selectable preferred direction depending on the magnetic field geometry and the selected AC frequency in the converter coil.
  • German publication DE 26 55 804 it is known further that the transducer or winding geometry specifies the track wavelength of the ultrasonic wave generated by electrodynamic means.
  • the known ultrasonic transducers or ultrasonic devices shown above are not suitable for use at high temperatures due to their design.
  • the measures for the most resonant operation of the transmitter and receiver converters described in the German specification 26 55 804 do not take into account the influence of longer cable lengths between the converter and the signal processing unit.
  • preamplifiers are placed near the transducers at long distances between the signal processing unit and transducers, which pre-process the signal to prevent inductive and capacitive interference effects of the signal lines.
  • the high-frequency signal generated by the transducers which has an amplitude in the range of only about 1 millivolt, is processed in such a way that the signal can be transported from the preamplifiers to the signal processing unit over longer lengths.
  • preamplifiers must be placed near the transducers and that the electronic components arranged in the preamplifiers are neither radiation-resistant nor temperature-resistant disadvantageously the result that an ultrasound device constructed in this way cannot be used under these extreme conditions, ie high temperature, high radiation exposure and risk of splashing water.
  • the object of the invention is therefore to provide an ultrasound device and to further develop the above-mentioned ultrasound transducer in such a way that trouble-free operation is ensured with temperature cycles from 23 degrees Celsius to 300 degrees Celsius and the use of large transmission and reception line lengths, with no preamplifiers can and the converter should also be resistant to splash water and radiation in the entire temperature range mentioned above.
  • the magnet system consists of a soft magnetic housing open to the workpiece surface, within which a permanent magnet is aligned with its polar axis perpendicular to the workpiece surface and with the pole surface facing away from the workpiece surface Housing is held magnetically and is connected to the other pole face with a carrier receiving the transducer coil, that the electrical connection consists of a single or multi-core coaxial cable, which extends through an opening in the housing and is firmly connected to the same that at least one free
  • the wire end of the converter coil is flexible and is connected to one of the line wires of the coaxial cable and is soldered to the contact point (s) and the soldering points and the converter coil wires are resistant to high temperatures Plastic are insulated.
  • the housing is can-shaped and consists of soft iron. At Changing operating temperatures, it proves to be particularly advantageous to design the invention in such a way that the housing has a recess on the surface that abuts the pole face of the permanent magnet, the extent of which is parallel to the pole face so large that the edge of this pole face is separated from the Side surfaces of the recess at room temperature is included forming an air gap.
  • the use of Sm2Co17 as a permanent magnet material according to the invention advantageously ensures a high and temperature-stable remanence.
  • the carrier consists of a soft magnetic powder composite material with low electrical conductivity and high temperature resistance, for. B.
  • Corovac OF (company vacuum melt) and is connected to the permanent magnet held only magnetically. It is particularly advantageous to design the carrier as a truncated cone tapering towards the workpiece surface.
  • the carrier can also consist of a temperature-resistant non-magnetic material, e.g. B. made of ceramic or a temperature-resistant, radiation-resistant and waterproof plastic compound. PEEKK is particularly suitable for this.
  • the carrier is designed like a comb with grooves open towards the workpiece surface.
  • the coaxial cable is advantageously steel-coated and welded to the housing at the opening.
  • the isolated solder joints are firmly connected to the housing.
  • two electrically independent converter coils are arranged in the carrier.
  • at least the wire end of the converter coil, which is flexibly connected to one of the line wires of the coaxial cable, is designed as a wire loop.
  • an ultrasonic device consisting of a plurality of electrodynamic ultrasonic transducers according to claim 1, in which one of the ultrasonic transducers can be controlled as a transmitter and at least one further ultrasonic transducer as a receiver, the windings of the transducer coils being arranged in a meandering manner and largely parallel to a workpiece surface and with electrical connections a signal triggering and signal processing unit, the object is achieved according to the invention in that the electrical connections consist of coaxial cables with a length of more than 10 m, that the transducer coil of the transmitter and the receiver consists of several meandering elements, so that the number of turns of each transducer coil is chosen is that the impedance of the converter coil compensates for the impedance of the coaxial cable and the inputs of the signal triggering and signal processing unit, the meandering elements of the transmitter each having an h have here number of turns than the respective meander elements of the receiver.
  • a particularly advantageous embodiment of the ultrasonic device according to the invention results from the fact that when using an 80 m long coaxial cable, the transducer coil of the transmitter consists of three meandering elements with 15 turns each and the transducer coil of the receiver consists of three meandering elements, each with 7 turns, and that the Track wavelength 8 mm and the winding length is 27 mm. All resulting inductances and capacitances compensate each other in such a way that the entire electrical arrangement is ohmic.
  • the high temperature resistance of the Corovac OF material thus also guarantees trouble-free operation at high temperatures, up to 300 degrees Celsius.
  • the connection of the individual parts to one another, which is brought about by exclusively magnetic forces, ensures in a particularly advantageous manner that no mechanical stresses occur in the transducer, even when the coefficients of thermal expansion vary widely. This advantage comes into play especially when the converter is briefly exposed to high temperature differences or temperature cycles.
  • the use of the plastic PEEKK (for example Hostatec from Hoechst) not only ensures high temperature resistance in the insulation area, but also advantageously uses the properties of radiation resistance and splash water resistance in the entire temperature range between room temperature and 300 degrees Celsius.
  • Corovac OF it proves to be particularly advantageous to design the support as a truncated cone tapering towards the workpiece surface.
  • Corovac OF As the material for the carrier, it is possible to use ceramic or PEEKK.
  • the connection between the carrier and the permanent magnet is brought about by a correspondingly temperature-resistant adhesive.
  • the comb-like configuration of the carrier with grooves open toward the workpiece surface has the advantage of receiving the converter coil wires in a very simple manner and of facilitating the energy transfer between the workpiece surface and the converter coil.
  • the use of the steel-sheathed coaxial cable, which is welded to the housing at the opening, guarantees interference-free operation in a fixed installation, for example, even under operating conditions according to the task.
  • the arrangement of two electrically independent transducer coils on a common carrier has the advantage that the transmitting and receiving location are concentrated on a common ultrasonic transducer.
  • the electrodynamic ultrasonic transducer at high temperature cycles, the fixed arrangement of the individual parts is ensured, while at the same time providing a mechanically stress-free connection, in that the housing has a recess on the surface that bears on the pole face of the permanent magnet, the recess of which is parallel to the pole face Extent is so large that the permanent magnet is enclosed on the side surfaces around this pole surface at room temperature to form an air gap.
  • This air gap can be chosen so that it closes when a specified high temperature is used. Under these conditions of thermal expansion effects, it proves to be particularly advantageous that at least the wire end of the transducer coil, which is flexibly connected to one of the line wires of the coaxial cable, is designed as a wire loop.
  • the advantage of the ultrasound device proposed according to the invention is that the signal triggering or signal processing unit can be arranged at a considerable distance from the transmitter or receiver, especially for use in or at systems up to 300 degrees Celsius. It is essential here that the signal can not be processed, for example by preamplifiers.
  • the high-frequency signal, with an amplitude of approximately 1 mV, can be transmitted over the entire distance between the converter and signal processing without electronic effort.
  • the electrical adaptation proposed according to the invention means that trouble-free operation is guaranteed even under these extreme conditions.
  • the use of the converter coil which is matched according to the invention with respect to the coaxial cable results in a particularly advantageous suitability for, for example, a fixed installation of a plurality of transmitters and receivers in a system.
  • the proposed ultrasonic device is therefore particularly suitable for checking fill levels and flows in hot containers.
  • the other properties also make it particularly suitable for use in power plants.
  • the individual ultrasonic transducers which are used, for example, in a pipeline system of a power plant for a checking device, can be used by Responsibility can be summarized in a monitoring control center using the 80 m long cables.
  • Figure 1 shows the electrodynamic ultrasonic transducer in a sectional view.
  • the housing 2 made of soft iron has a recess 11 or lateral holding projections where the permanent magnet 3 abuts.
  • the dimensions of this recess 11 or these projections are designed such that an air gap is present between the side surfaces of the magnet 3 and the projections 11 at room temperature. This ensures that even with the present materials, despite different expansion coefficients, there is no mechanical stress at higher temperatures.
  • the dimensions of the depth of the recess 11 or the projections are, however, such that a desired position of the permanent magnet 3 within the housing 2 is nevertheless given.
  • the coaxial cable 7 is passed laterally through a bore 8 in the housing 2 and glued to the outside of the housing in a watertight manner.
  • the signal line 12 of the coaxial cable 7 extends into the interior of the housing 2 and forms the electrical contact via a brazed connection and a wire loop 9 the converter wires.
  • the brazing point is generously insulated and cast with a block 13 made of PEEKK.
  • the block 13 is firmly glued to the housing inner wall near the entry point of the coaxial cable into the housing 2.
  • one of the loose converter wire ends 9 is led, for example as a loop, to the brazing point.
  • This wire 9, like the wires of the converter coil 5, is insulated with PEEKK.
  • the carrier 6 for the transducer coil 5 is designed and arranged such that it bears against the permanent magnet 3 over a smooth, flat surface in the position shown and has the comb-like toothing on the side facing the workpiece surface 1, in which the transducer wires 5 are arranged.
  • the carrier 6 consists of Corovac OF.
  • the magnetic field lines are introduced into the workpiece surface 1 by the permanent magnet 3 via the carrier 6, the soft iron housing 2 then bringing about the necessary magnetic inference of the field lines. All individual magnetic parts, ie housing 2, permanent magnet 3 and Corovac carrier 6 are held together exclusively by magnetic forces.
  • the entire ultrasonic transducer is free of mechanical stresses and thus also free of possible operational disturbances, even with different thermal expansion coefficients in a temperature range up to 300 degrees Celsius .
  • the Sm2CO17 permanent magnet material used has the specific property of maintaining high remanence even in the temperature range mentioned.
  • the use of the PEEKK insulation material ensures the splash water and radiation resistance even at higher temperatures, ie up to 320 degrees Celsius.
  • Figure 2 shows a detailed drawing of the carrier.
  • the side view poses the carrier 6 similar to that shown in Figure 1.
  • the carrier 6 is designed so that a comb-like toothing is also formed in the plan view along the line AA in the edge region of the longitudinal sides 14.
  • An embodiment of this type is only relevant when using non-magnetic materials, such as. B. ceramic or PEEKK.
  • Corovac a configuration of the carrier, as shown in the top view, would not be suitable, because strongly inhomogeneous magnetic field line profiles would occur on the additional comb-like teeth.
  • FIG. 3 shows an electrodynamic ultrasound transducer for the special application of vertical insonification.
  • the transmitting and receiving coils are wound on a common carrier 6 made of Corovac.
  • the coaxial cable 7 is in this case multi-core, i. H. here provided with two signal lines 12, 12 '.
  • the resulting soldered connections are embedded in a common insulation block 13 made of PEEKK and, as shown in FIG. 1, connected to the inner wall of the housing.
  • the carrier 6, which in this case consists of Corovac OF, is designed in the shape of a truncated cone and is oriented such that the truncated cone tapers towards the workpiece surface 1.
  • the concentrator effect thus achieved improves the efficiency of the ultrasound generation.
  • the common arrangement of the transmitting and receiving transducer coil in a common ultrasonic transducer is not mandatory, i. H. Transmitter and receiver transducer coils can also be accommodated in various ultrasonic transducers.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Length Measuring Devices Characterised By Use Of Acoustic Means (AREA)
EP91250095A 1990-05-21 1991-04-09 Elektrodynamischer Ultraschallwandler und Ultraschalleinrichtung Revoked EP0458426B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4016741A DE4016741C1 (enExample) 1990-05-21 1990-05-21
DE4016741 1990-05-21

Publications (3)

Publication Number Publication Date
EP0458426A2 EP0458426A2 (de) 1991-11-27
EP0458426A3 EP0458426A3 (en) 1993-02-24
EP0458426B1 true EP0458426B1 (de) 1995-02-01

Family

ID=6407099

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91250095A Revoked EP0458426B1 (de) 1990-05-21 1991-04-09 Elektrodynamischer Ultraschallwandler und Ultraschalleinrichtung

Country Status (2)

Country Link
EP (1) EP0458426B1 (enExample)
DE (2) DE4016741C1 (enExample)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021081307A1 (en) * 2019-10-25 2021-04-29 Molex, Llc Ultrasonic patch transducer for monitoring the condition of a structural asset

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3963980A (en) * 1973-08-29 1976-06-15 Jury Mikhailovich Shkarlet Ultrasonic instrument for non-destructive testing of articles with current-conducting surface
CA1063710A (en) * 1976-08-31 1979-10-02 Erazm A. Willy Electromagnetic transducer
DE2655804C3 (de) * 1976-12-09 1980-01-24 Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V., 8000 Muenchen Elektrodynamischer Ultraschallwellenwandler
US4058002A (en) * 1976-12-23 1977-11-15 The United States Of America As Represented By The Secretary Of The Air Force Dispersive electromagnetic surface acoustic wave transducer

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021081307A1 (en) * 2019-10-25 2021-04-29 Molex, Llc Ultrasonic patch transducer for monitoring the condition of a structural asset
US12449404B2 (en) 2019-10-25 2025-10-21 Molex, Llc Ultrasonic patch transducer for monitoring the condition of a structural asset

Also Published As

Publication number Publication date
EP0458426A2 (de) 1991-11-27
DE59104457D1 (de) 1995-03-16
EP0458426A3 (en) 1993-02-24
DE4016741C1 (enExample) 1991-06-20

Similar Documents

Publication Publication Date Title
DE68915241T2 (de) Nach dem Coriolis-Prinzip arbeitender Hochtemperatur-Massendurchflussmesser.
DE4016740C1 (enExample)
DE19649682A1 (de) Vorrichtung zur berührungslosen Signalübertragung zwischen beweglichen Einheiten
DE102004023815A1 (de) Antennenanordnung und Verwendung der Antennenanordnung
DE2162196B2 (de) Wellentypwandler
DE69634988T2 (de) Akustische wandlerkomponenten
DE202013103566U1 (de) Optischer Resonanzscanner
DE4124103C1 (enExample)
EP1658668A1 (de) Anordnung zur berührungslosen induktiven bertragung elektrischer leistung
EP0458426B1 (de) Elektrodynamischer Ultraschallwandler und Ultraschalleinrichtung
DE102005062874A1 (de) Vorrichtung zum Senden und/oder Empfangen elektromagnetischer HF-Signale
DE3637366C2 (enExample)
DE3904440A1 (de) Elektrodynamischer wandlerkopf
EP0069865B1 (de) Elektrodynamischer Wandlerkopf
DE10133171C1 (de) Verfahren und Einrichtung zur Positionserfassung
DE60002324T2 (de) Schutzvorrichtung gegen elektromagnetische strahlung mit dichtungen
DE112005000106T5 (de) Elektromagnetisch-Akustischer Messwandler
DE102009003924A1 (de) Sensor nach dem Laufzeitprinzip mit einer Detektoreinheit für mechanisch-elastische Dichte-Wellen
DE102004045458B4 (de) Übertragungsstrecke
DE102011111849A1 (de) Linearbewegungsvorrichtung mit an einem Bimetallabschnitt befestigter Abtastvorrichtung einer Wegmesseinrichtung
DE3042645C2 (de) Elektrodynamischer zumindest je eine Erreger- u. eine Empfangsspule umfassender Ultraschallwandler
DE3207305C2 (de) Magnetostriktiver Ultraschallwandler, insbesondere zur Füllstandsmessung in heißen Flüssigkeiten
DE19954579C1 (de) Vorrichtung zur Erfassung des Energieverbrauchs einer Heizungsanlage
DE102012005528A1 (de) Energieübertragungssystem mit einem an ein Primärleitersystem induktiv koppelbaren Modul
DE69126427T2 (de) Leitungskupplungstransformator

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: A2

Designated state(s): DE FR IT

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR IT

17P Request for examination filed

Effective date: 19930323

17Q First examination report despatched

Effective date: 19940322

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR IT

ITF It: translation for a ep patent filed
ET Fr: translation filed
REF Corresponds to:

Ref document number: 59104457

Country of ref document: DE

Date of ref document: 19950316

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19950320

Year of fee payment: 5

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: SIEMENS AG

Effective date: 19951031

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19960521

Year of fee payment: 6

PLBF Reply of patent proprietor to notice(s) of opposition

Free format text: ORIGINAL CODE: EPIDOS OBSO

RDAG Patent revoked

Free format text: ORIGINAL CODE: 0009271

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

Free format text: STATUS: PATENT REVOKED

27W Patent revoked

Effective date: 19960627