EP0321759B1 - Electromagnetic shock waves source - Google Patents

Electromagnetic shock waves source Download PDF

Info

Publication number
EP0321759B1
EP0321759B1 EP88120217A EP88120217A EP0321759B1 EP 0321759 B1 EP0321759 B1 EP 0321759B1 EP 88120217 A EP88120217 A EP 88120217A EP 88120217 A EP88120217 A EP 88120217A EP 0321759 B1 EP0321759 B1 EP 0321759B1
Authority
EP
European Patent Office
Prior art keywords
membrane
diaphragm
wave source
shock
copper
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP88120217A
Other languages
German (de)
French (fr)
Other versions
EP0321759A2 (en
EP0321759A3 (en
Inventor
Josef Dipl.-Ing. Katona
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.)
Dornier Medizintechnik GmbH
Original Assignee
Dornier Medizintechnik GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dornier Medizintechnik GmbH filed Critical Dornier Medizintechnik GmbH
Publication of EP0321759A2 publication Critical patent/EP0321759A2/en
Publication of EP0321759A3 publication Critical patent/EP0321759A3/en
Application granted granted Critical
Publication of EP0321759B1 publication Critical patent/EP0321759B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G10MUSICAL INSTRUMENTS; ACOUSTICS
    • G10KSOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K9/00Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
    • G10K9/12Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated

Definitions

  • the invention relates to an electromagnetic shock wave source as is known from DE-A-35 05 894.
  • Electromagnetic shock wave generation is used, among other things, in extracorporeal stone crushing (DE 33 28 066 A) and is also suitable for other therapeutic methods in which shock waves are used.
  • shock tube In the magazine "Akustician Beihefte", 1962, Issue 1, pages 158 to 202, the structure of a so-called shock tube is described.
  • a copper membrane is located in front of a flat coil, separated by an insulating film.
  • a tube filled with water connects to this copper membrane.
  • a voltage in the range of 2 - 20 kV to the flat coil, a magnetic field is induced in the copper membrane, which causes repulsive forces that push the membrane away from the coil.
  • Such a shock tube is used, for example, for chemical substance testing.
  • EP 212 352 A1 discloses an ultrasound generator which contains a piezoelectric transducer which is constructed from a plurality of active layers and contains two lead plates for electrical contacting and for acoustic coupling.
  • a lithotripter with a generic electromagnetic shock wave source is known from EP 278 304 A1.
  • the shock wave source contains a base body, a wire coil, an insulation film and a copper membrane. This latter document can only be used to assess novelty, in accordance with Article 54 (3) EPC.
  • DE-A-35 05 894 describes a shock tube which comprises a coil. There is an insulating film on both sides of the coil. A membrane made of electrically conductive material connects to the insulating film.
  • the object of the invention is to improve such a shock wave source in such a way that efficiency and service life are increased.
  • the preferred metals used are stainless steel for the high-strength membrane and copper or silver for the highly conductive membranes.
  • Preferred dimensions are: Noble jet membrane: 0.1 - 0.2 mm Copper membrane: 0.05 - 0.2 mm Insulation film: 0.025 - 0.125 mm
  • any number of combinations are possible in the number and thickness of the insulating foils or metal membranes. However, a total thickness of up to 1 mm should not be exceeded.
  • the shock wave source according to the invention here consists of a basic body 1, a wire coil 2, an insulation film 3, a copper membrane 4, a further insulation film 5, a second copper membrane 6, a further insulation film 7 and a stainless steel membrane 8, which is grounded. Designs with more than two highly conductive metal foils 4, 6 are possible, but not shown.
  • the individual layers are connected to one another in a conventional manner, for example by gluing.
  • the figure shows the shock wave source on a greatly enlarged scale. A total thickness of up to 1.0 mm is realistic.
  • the potential curve U is shown during the application of a high voltage.
  • the coil 2 is at the high potential U0.
  • the stainless steel membrane 8 is at earth potential.
  • the copper membranes 4 and 6 are each at potentials that lie between the value U0 and 0. Within the insulation foils 3, 5 and 7, the potential U falls from the higher value to a lower one.
  • FIG. 2 shows the current density distribution in a 0.2 mm thick copper membrane and the current density distribution in two 0.1 mm thick copper membranes, which are separated by an insulation film. Due to the skin effect, the current density at high frequencies is not evenly distributed over the conductor cross-section. The maximum depth of penetration at the frequency used is approx. 0.2 mm.
  • the distribution of the current density is shown schematically in FIG. 2. As can be seen from this, the integral over the current density is larger when using two membranes. This increases the repulsive forces and the amplitude of the pressure pulse generated. In the case of well-conductive membranes whose thicknesses are greater than 0.4 mm, the current density is zero in the inner region. This is not the case with a layered membrane. The distribution of the current density is similar in each membrane.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Surgical Instruments (AREA)
  • Building Environments (AREA)

Description

Die Erfindung betrifft eine elektromagnetische Stosswellenquelle wie sie aus DE-A-35 05 894 bekannt ist.The invention relates to an electromagnetic shock wave source as is known from DE-A-35 05 894.

Die elektromagnetische Stosswellenerzeugung (EMSE) wird unter anderem bei der extrakorporalen Steinzerkleinerung eingesetzt (DE 33 28 066 A) und ist auch für andere therapeutische Verfahren geeignet, bei denen Stosswellen verwendet werden.Electromagnetic shock wave generation (EMSE) is used, among other things, in extracorporeal stone crushing (DE 33 28 066 A) and is also suitable for other therapeutic methods in which shock waves are used.

In der Zeitschrift "Akustische Beihefte", 1962, Heft 1, Seiten 158 bis 202, ist der Aufbau eines sogenannten Stosswellenrohres beschrieben. Vor einer Flachspule, durch eine Isolierfolie getrennt, befindet sich eine Kupfermembran. An dieser Kupfermembran schliesst ein mit Wasser gefülltes Rohr an. Durch Anlegen einer Spannung im Bereich von 2 - 20 kV an die Flachspule wird in der Kupfermembran ein Magnetfeld induziert, welches Abstosskräfte bewirkt, die die Membran von der Spule wegdrücken. Hierdurch entsteht ein ebener Druckpuls, der im wassergefüllten Rohr zu einer steilen Stosswelle wird und am Rohrende für Experimente zur Verfügung steht. Eingesetzt wird ein solches Stosswellenrohr zum Beispiel zu Stoffuntersuchungen in der Chemie.In the magazine "Akustische Beihefte", 1962, Issue 1, pages 158 to 202, the structure of a so-called shock tube is described. A copper membrane is located in front of a flat coil, separated by an insulating film. A tube filled with water connects to this copper membrane. By applying a voltage in the range of 2 - 20 kV to the flat coil, a magnetic field is induced in the copper membrane, which causes repulsive forces that push the membrane away from the coil. This creates a flat pressure pulse that becomes a steep shock wave in the water-filled pipe and is available for experiments at the end of the pipe. Such a shock tube is used, for example, for chemical substance testing.

Aus der EP 212 352 A1 ist ein Ultraschallgenerator bekannt, der einen piezoelektrischen Wandler enthält, der aus mehreren aktiven Schichten aufgebaut ist und zwei Bleiplatten zur elektrischen Kontaktierung und zur akustischen Ankoppelung enthält.EP 212 352 A1 discloses an ultrasound generator which contains a piezoelectric transducer which is constructed from a plurality of active layers and contains two lead plates for electrical contacting and for acoustic coupling.

Aus der EP 278 304 A1 ist ein Lithotripter mit einer gattungsgemäßen elektromagnetischen Stosswellenquelle bekannt. Die Stosswellenquelle enthält einen Grundkörper, eine Drahtspule, eine Isolationsfolie und eine Kupfermembran. Diese letzgenannte Schrift ist nur zur Beurteilung der Neuheit heranzuziehen, gemäß Artikel 54(3) EPÜ.A lithotripter with a generic electromagnetic shock wave source is known from EP 278 304 A1. The shock wave source contains a base body, a wire coil, an insulation film and a copper membrane. This latter document can only be used to assess novelty, in accordance with Article 54 (3) EPC.

In der DE-A-35 05 894 ist ein Stosswellenrohr beschrieben, das eine Spule umfaßt. Auf beiden Selten der Spule befindet sich je eine Isolierfolie. An die Isolierfolie schließt sich jeweils eine Membran aus elektrisch leitfähigem Material an.DE-A-35 05 894 describes a shock tube which comprises a coil. There is an insulating film on both sides of the coil. A membrane made of electrically conductive material connects to the insulating film.

Aufgabe der Erfindung ist es, eine solche Stosswellenquelle dahingehend zu verbessern, dass Wirkungsgrad und Lebensdauer erhöht werden.The object of the invention is to improve such a shock wave source in such a way that efficiency and service life are increased.

Diese Aufgabe wird erfindungsgemäß gelöst von einer Stosswellenquelle mit den Merkmalen des Anspruchs 1. Ausführungen der Erfindung sind Gegenstände von Unteransprüchen.This object is achieved according to the invention by a shock wave source with the features of claim 1. Embodiments of the invention are the subject of subclaims.

Die Erfindung hat folgende Vorteile:

  • Wirkungsgradverluste durch eine geerdete Kupfermembran werden vermieden. Die Erwärmung des Gesamtsystems wird wegen des verbesserten Wirkungsgrades verringert.
  • Der Skineffekt wirkt sich nicht mehr begrenzend auf die gesamte Dicke der gut leitfähigen Membran aus, wie anhand von Figur 2 gezeigt ist. Dennoch können nun mehrere Membranen hintereinander gesetzt werden, deren Gesamtdicke größer ist als die einer einzelnen Membran.
  • Die Potentialaufteilung zwischen Spule und der geerdeten abschliessenden Metallmembran wird günstiger, da die zwischenliegenden Membranen gegen die abschliessende Metallmembran isoliert sind und deshalb beim Anlegen einer hohen Spannung ein bestimmtes, niedrigeres Potential annehmen. Dies erhöht die Lebensdauer, denn die Lebensdauer des Systems ist bestimmt durch die Durchschlagfestigkeit der Isolationsschicht zwischen Drahtspule und Membran. Aufgrund der günstigeren Potentialaufteilung wird die Isolationsschicht elektrisch weniger stark beansprucht, das heisst die Lebensdauer erhöht sich.
  • Die gut leitfähigen Membrane können direkt auf die Spule aufgelegt werden, sofern die Isolationsschicht zwischen ihren und der abschliessenden Membran entsprechend ausgelegt ist. Hieraus folgt eine weitere Verbesserung der Ankopplung der Membran an die Drahtspule, da das Streufeld minimiert wird.
  • Verringerung der Wirbelstromverluste.
The invention has the following advantages:
  • Efficiency losses due to an earthed copper membrane are avoided. The heating of the overall system is reduced due to the improved efficiency.
  • The skin effect no longer has a limiting effect on the entire thickness of the highly conductive membrane, as shown in FIG. 2. Nevertheless, several membranes can now be placed one behind the other, the total thickness of which is greater than that of a single membrane.
  • The potential distribution between the coil and the grounded, final metal membrane becomes more favorable because the membranes in between are isolated from the final metal membrane and therefore assume a certain, lower potential when a high voltage is applied. This increases the lifespan, because the lifespan of the system is determined by the dielectric strength of the insulation layer between the wire coil and the membrane. Due to the more favorable potential distribution, the insulation layer is subjected to less electrical stress, which means that the service life increases.
  • The highly conductive membrane can be placed directly on the coil, provided the insulation layer between its and the final membrane is designed accordingly is. This results in a further improvement in the coupling of the membrane to the wire coil, since the stray field is minimized.
  • Reduction of eddy current losses.

Als bevorzugte Metalle werden für die hochfeste Membran Edelstahl und für die gut leitfähigen Membranen Kupfer oder Silber verwendet.The preferred metals used are stainless steel for the high-strength membrane and copper or silver for the highly conductive membranes.

Bevorzugte Dimensionen sind: Edelstrahlmembran: 0,1 - 0,2 mm Kupfermembran: 0,05 - 0,2 mm Isolationsfolie: 0,025 - 0,125 mm Preferred dimensions are: Noble jet membrane: 0.1 - 0.2 mm Copper membrane: 0.05 - 0.2 mm Insulation film: 0.025 - 0.125 mm

In der Anzahl und Dicke der Isolationsfolien oder der Metallmembranen sind beliebige Kombinationen möglich. Allerdings sollte eine Gesamtdicke von bis zu 1 mm nicht überschritten werden.Any number of combinations are possible in the number and thickness of the insulating foils or metal membranes. However, a total thickness of up to 1 mm should not be exceeded.

Die Erfindung wird anhand zweier Figuren näher erläutert.

Figur 1
zeigt eine erfindungsgemässe Stosswellenquelle,
Figur 2
zeigt den Stromdichteverlauf in verschiedenen Membranen.
The invention is explained in more detail with reference to two figures.
Figure 1
shows a shock wave source according to the invention,
Figure 2
shows the current density curve in different membranes.

Die Figur 1 zeigt in ihrer oberen Hälfte den Aufbau einer bevorzugten Ausführungsform einer erfindungsgemässen Stosswellenquelle und in ihrer unteren Hälfte den Potentialverlauf beim Anlegen einer hohen Spannung an die Spule.
Die erfindungsgemässe Stosswellenquelle besteht hier aus einem Grundköprer 1, einer Drahtspule 2, einer Isolationsfolie 3, einer Kupfermembran 4, einer weiteren Isolationsfolie 5, einer zweiten Kupfermembran 6, einer weiteren Isolationsfolie 7 und eine Edelstahlmembran 8, die geerdet ist. Möglich, aber nicht gezeigt, sind Ausführungen mit mehr als zwei gut leitenden Metallfolien 4, 6. Die einzelnen Schichten sind auf konventionelle Weise, zum Beispiel durch Kleben, miteinander verbunden.
Die Figur zeigt die Stosswellenquelle in stark vergrössertem Maßstab. Realistisch ist eine Gesamtdicke bis zu 1,0 mm.
Im unteren Teil der Figur ist der Potentialverlauf U während des Anlegens einer hohen Spannung gezeigt. Die Spule 2 liegt auf dem hohen Potential U₀. Die Edelstahlmembran 8 liegt auf Erdpotential.
Die Kupfermembranen 4 und 6 liegen jeweils auf Potentialen, die zwischen dem Wert U₀ und 0 liegen. Innerhalb der Isolationsfolien 3, 5 und 7 fällt das Potential U jeweils vom höheren Wert auf einen niedrigeren.
1 shows in its upper half the structure of a preferred embodiment of a shock wave source according to the invention and in its lower half the potential curve when a high voltage is applied to the coil.
The shock wave source according to the invention here consists of a basic body 1, a wire coil 2, an insulation film 3, a copper membrane 4, a further insulation film 5, a second copper membrane 6, a further insulation film 7 and a stainless steel membrane 8, which is grounded. Designs with more than two highly conductive metal foils 4, 6 are possible, but not shown. The individual layers are connected to one another in a conventional manner, for example by gluing.
The figure shows the shock wave source on a greatly enlarged scale. A total thickness of up to 1.0 mm is realistic.
In the lower part of the figure, the potential curve U is shown during the application of a high voltage. The coil 2 is at the high potential U₀. The stainless steel membrane 8 is at earth potential.
The copper membranes 4 and 6 are each at potentials that lie between the value U₀ and 0. Within the insulation foils 3, 5 and 7, the potential U falls from the higher value to a lower one.

Figur 2 zeigt oben die Stromdichteverteilung in einer 0,2 mm dicken Kupfermembran und unten die Stromdichteverteilung in zwei 0,1 mm dicken Kupfermembranen, die von einer Isolationsfolie getrennt sind. Aufgrund des Skineffektes verteilt sich die Stromdichte bei hohen Frequenzen nicht gleichmässig über den Leiterquerschnitt. Die maximale Eindringtiefe bei der verwendeten Frequenz beträgt ca. 0,2 mm. Die Verteilung der Stromdichte ist schematisch in der Figur 2 gezeigt.
Wie daraus ersichtlich wird, ist das Integral über die Stromdichte bei Verwendung zweier Membranen grösser. Damit erhöhen sich die Abstossungskräfte und die Amplitude des erzeugten Druckimpules.
Bei gut leitfähigen Membranen, deren Dicken grösser als 0,4 mm sind, ist im inneren Bereich die Stromdichte Null. Bei einer geschichteten Membran ist dies nicht der Fall. Die Verteilung der Stromdichte ist in jeder Membran ähnlich.
FIG. 2 shows the current density distribution in a 0.2 mm thick copper membrane and the current density distribution in two 0.1 mm thick copper membranes, which are separated by an insulation film. Due to the skin effect, the current density at high frequencies is not evenly distributed over the conductor cross-section. The maximum depth of penetration at the frequency used is approx. 0.2 mm. The distribution of the current density is shown schematically in FIG. 2.
As can be seen from this, the integral over the current density is larger when using two membranes. This increases the repulsive forces and the amplitude of the pressure pulse generated.
In the case of well-conductive membranes whose thicknesses are greater than 0.4 mm, the current density is zero in the inner region. This is not the case with a layered membrane. The distribution of the current density is similar in each membrane.

Claims (4)

  1. Shock-wave source comprising a base body (1), at least one wire coil (2), an insulation foil (3) and a first metal diaphragm (8), as well as at least one additional metal diaphragm (4, 6) of good conductivity, which is separated from the first metal diaphragm (8) by at least one insulation foil (7) and highly rigid, and that the at least one additional metal diaphragm (4, 6) of good conductivity is provided between the coil (2) and the first metal diaphragm (8), and that furthermore an insulation foil (5) is provided between each additional metal diaphragm (4, 6).
  2. Shock waves according to claim 1, characterised in that the metal diaphragms (4, 6) of good conductivity are made of copper or silver.
  3. Shock-wave source according to at least one of the above claims, characterised in that the highly rigid diaphragm (8) is made of stainless steel.
  4. Shock-wave source according to at least one of the above claims, characterised by the following materials and thicknesses: - stainless steel diaphragm: 0.1 - 0.2 mm - insulation foil: 0.025 - 0.125 mm - copper diaphragm: 0.05 - 0.2 mm
EP88120217A 1987-12-23 1988-12-03 Electromagnetic shock waves source Expired - Lifetime EP0321759B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3743822 1987-12-23
DE19873743822 DE3743822A1 (en) 1987-12-23 1987-12-23 ELECTROMAGNETIC SHAFT SOURCE

Publications (3)

Publication Number Publication Date
EP0321759A2 EP0321759A2 (en) 1989-06-28
EP0321759A3 EP0321759A3 (en) 1989-10-04
EP0321759B1 true EP0321759B1 (en) 1994-06-01

Family

ID=6343441

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88120217A Expired - Lifetime EP0321759B1 (en) 1987-12-23 1988-12-03 Electromagnetic shock waves source

Country Status (5)

Country Link
US (1) US4924858A (en)
EP (1) EP0321759B1 (en)
JP (1) JPH0741043B2 (en)
DE (1) DE3743822A1 (en)
ES (1) ES2056880T3 (en)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3907605C2 (en) * 1989-03-09 1996-04-04 Dornier Medizintechnik Shock wave source
DE4130796A1 (en) * 1990-09-27 1992-04-02 Siemens Ag ELECTRICALLY DRIVABLE SHOCK WAVE SOURCE
US5233972A (en) * 1990-09-27 1993-08-10 Siemens Aktiengesellschaft Shockwave source for acoustic shockwaves
DE4041063A1 (en) * 1990-12-20 1992-06-25 Siemens Ag Removal of artificial joints - with focussed ultrasonic head to loosen cement around joint support
DE4125088C1 (en) * 1991-07-29 1992-06-11 Siemens Ag, 8000 Muenchen, De
DE4201139A1 (en) * 1992-01-17 1993-07-22 Siemens Ag ELECTROMAGNETIC ACOUSTIC PRESSURE PULSE SOURCE WITH ELECTRICALLY CONDUCTIVE MEMBRANES
DE4228963C2 (en) * 1992-08-31 1998-10-22 Siemens Ag Pressure pulse source with a cavitation-resistant coated membrane
US7189209B1 (en) 1996-03-29 2007-03-13 Sanuwave, Inc. Method for using acoustic shock waves in the treatment of a diabetic foot ulcer or a pressure sore
US6390995B1 (en) 1997-02-12 2002-05-21 Healthtronics Surgical Services, Inc. Method for using acoustic shock waves in the treatment of medical conditions
DE10160595A1 (en) * 2001-12-10 2003-06-26 Dornier Medtech Holding Int Gmbh Electromagnetic shock or pressure wave source
DE102004013573B3 (en) * 2004-03-19 2005-09-01 Dornier Medtech Systems Gmbh Production of a traction impulse between electrically conducting structures comprises preparing the structures insulated from each other and lying next to each other, producing a magnetic field and switching off the magnetic field
DE102004036526B4 (en) * 2004-07-28 2008-06-05 Dornier Medtech Systems Gmbh Shock wave source and shock wave treatment device
CN1878427A (en) * 2005-06-07 2006-12-13 日本电产鸽株式会社 Speaker
CN1882195A (en) * 2005-06-07 2006-12-20 日本电产鸽株式会社 Speaker
US9997189B2 (en) * 2016-11-07 2018-06-12 Seagate Technology Llc Three dimensional electric field data storage device utilizing shockwaves and a light source
US10056146B2 (en) 2016-11-07 2018-08-21 Seagate Technology Llc Electric field storage device
US20220072326A1 (en) * 2020-09-10 2022-03-10 Moshe Ein-Gal Combined pulsed electromagnetic field and low intensity shockwave system and method

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3505894A1 (en) * 1985-02-20 1986-08-21 Siemens AG, 1000 Berlin und 8000 München Shock wave tube with coil and diaphragm

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3447440A1 (en) * 1984-12-27 1986-07-03 Siemens AG, 1000 Berlin und 8000 München SHOCK SHAFT PIPE FOR THE CRUSHING OF CONCRETE
US4718421A (en) * 1985-08-09 1988-01-12 Siemens Aktiengesellschaft Ultrasound generator
EP0256203A1 (en) * 1986-06-05 1988-02-24 Siemens Aktiengesellschaft Shock wave generator for the disintegration of concretions in a living body by non-contacting means
US4796608A (en) * 1986-06-16 1989-01-10 Siemens Aktiengesellschaft Shock wave generator for an apparatus for non-contacting disintegration of calculi in the body of a life form
DE8627238U1 (en) * 1986-10-06 1988-02-04 Siemens AG, 1000 Berlin und 8000 München Shock wave source
EP0278304A1 (en) * 1987-02-04 1988-08-17 Siemens Aktiengesellschaft Lithotripter with an integrated positioning device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3505894A1 (en) * 1985-02-20 1986-08-21 Siemens AG, 1000 Berlin und 8000 München Shock wave tube with coil and diaphragm

Also Published As

Publication number Publication date
ES2056880T3 (en) 1994-10-16
DE3743822C2 (en) 1989-10-12
DE3743822A1 (en) 1989-07-13
US4924858A (en) 1990-05-15
EP0321759A2 (en) 1989-06-28
JPH0741043B2 (en) 1995-05-10
EP0321759A3 (en) 1989-10-04
JPH01280451A (en) 1989-11-10

Similar Documents

Publication Publication Date Title
EP0321759B1 (en) Electromagnetic shock waves source
DE69635308T2 (en) PIEZOELECTRIC TRANSFORMER
EP0025092B1 (en) Ultrasonic transducer assembly and process for its production
DE69837416T2 (en) Conductive back element for a composite transducer
DE69231190T2 (en) ACTIVE PANEL WITH HIGH TRANSMISSION DAMPING
DE69710314T2 (en) SOUND TRANSDUCER WITH SEVERAL ELEMENTS AND COMMON EARTH ELECTRODE
DE3214789A1 (en) DYNAMICALLY FOCUSING ULTRASONIC transducer
EP0212352A1 (en) Ultrasonic generator
DE2915761A1 (en) DEVICE FOR ULTRASONIC EXAMINATION OF AN OBJECT
EP0006623A2 (en) Ultrasonic transducer
DE2824995A1 (en) MULTICELLED X-RAY DETECTOR
DE3443869A1 (en) CONVERTER ARRANGEMENT FOR HYDROPHONES
DE3215242A1 (en) ULTRASONIC HEAD
DE4130798A1 (en) SHOCK WAVE SOURCE FOR ACOUSTIC SHOCK WAVES
DE2139200A1 (en) Surface wave converter
DE3505894A1 (en) Shock wave tube with coil and diaphragm
DE3709533C2 (en)
DE4125088C1 (en)
DE3784078T2 (en) ECHOGRAPHY CONVERTER WITH CONNECTOR.
DE3019410A1 (en) Ultrasound transducer for medical diagnostics or material testing - has numerous transducing elements and contacting simplified by using metal coated plastics foil for contacting
EP1911401B1 (en) Plate segment for a multi part patient support plate and an operating table
DE68918871T2 (en) METHOD AND DEVICE FOR THE BIDIMENSIONAL LOCALIZATION OF UNCHARGED PARTICLES, ESPECIALLY AT A LOW COUNTING RATE.
DE2444023A1 (en) ELECTROSTATIC CONVERTER
DE3502770A1 (en) METHOD FOR PRODUCING A FLAT COIL AND FLAT COIL FOR A SHOCK SHAFT PIPE
EP0160821B1 (en) Apparatus for reading a two-dimensional charge image using an array

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): CH ES IT LI NL

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): CH ES IT LI NL

17P Request for examination filed

Effective date: 19890908

17Q First examination report despatched

Effective date: 19920810

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH ES IT LI NL

ITF It: translation for a ep patent filed
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2056880

Country of ref document: ES

Kind code of ref document: T3

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

Ref country code: NL

Payment date: 20071220

Year of fee payment: 20

Ref country code: ES

Payment date: 20071227

Year of fee payment: 20

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

Ref country code: IT

Payment date: 20071220

Year of fee payment: 20

Ref country code: CH

Payment date: 20071224

Year of fee payment: 20

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

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

Ref country code: NL

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20081203

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20081204

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

Ref country code: ES

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20081204