EP1059830A2 - Electrodynamic loudspeaker with a control device for an active vehicle noiceattenuator - Google Patents

Electrodynamic loudspeaker with a control device for an active vehicle noiceattenuator Download PDF

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Publication number
EP1059830A2
EP1059830A2 EP00110585A EP00110585A EP1059830A2 EP 1059830 A2 EP1059830 A2 EP 1059830A2 EP 00110585 A EP00110585 A EP 00110585A EP 00110585 A EP00110585 A EP 00110585A EP 1059830 A2 EP1059830 A2 EP 1059830A2
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EP
European Patent Office
Prior art keywords
voice coil
membrane
sensor
loudspeaker
marked
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.)
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EP00110585A
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German (de)
French (fr)
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EP1059830A3 (en
Inventor
Martin Unbehaun
Gerhard Zintel
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Faurecia Automobiltechnik GmbH
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Leistritz AG and Co Abgastechnik
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Publication of EP1059830A2 publication Critical patent/EP1059830A2/en
Publication of EP1059830A3 publication Critical patent/EP1059830A3/en
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • H04R3/002—Damping circuit arrangements for transducers, e.g. motional feedback circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N1/00—Silencing apparatus characterised by method of silencing
    • F01N1/06—Silencing apparatus characterised by method of silencing by using interference effect
    • F01N1/065—Silencing apparatus characterised by method of silencing by using interference effect by using an active noise source, e.g. speakers

Definitions

  • the invention relates to an electrodynamic loudspeaker, in particular for an active silencer of a motor vehicle.
  • Speakers of the in question standing type is a membrane over a voice coil from its central position periodically distracted.
  • There is a magnetic field to drive the voice coil that of an annular magnet with a pole core arranged centrally in it and an end face of the magnet facing the membrane Pole plate is generated. That with its field lines essentially magnetic field extending at right angles to the direction of movement of the voice coil is not completely homogeneous now, but is weakening in a more positive way or edge regions pointing in a negative direction of deflection.
  • the magnetic field is completely symmetrical, so that it is periodic in the axial direction oscillating voice coil in positive and negative deflection direction always is applied with the same force.
  • the membrane is additionally included mainly in these marginal areas a one-sided force component acting approximately in the positive direction of deflection acted upon and accordingly the middle position of the with the voice coil coupled membrane shifted accordingly.
  • this effect is practically negligible.
  • the more the vibration amplitudes increase the stronger the effect described causes Reduction of the efficiency of the speaker.
  • the diaphragm middle position shifts even more. This is a disadvantage especially with such speakers, the small dimensions due to the available installation space should have high performance, such as this for anti-noise speakers of active exhaust silencers is the case.
  • the object of the invention is one in terms of its efficiency above all To propose things in the higher power range to improved speakers.
  • a control device is provided with which a middle layer deviation of the membrane can be detected with the aid of a sensor and the voice coil with one counteracting the deviation DC voltage can be applied. So with such a control device can be recognized that the center position of the speaker membrane in a critical Area has moved. Depending on the shift in positive or negative The direction of deflection becomes a correspondingly polarized one which overlaps the control signal Correction voltage applied to the voice coil, causing the diaphragm is returned to its starting position. With such a design For example, speakers can achieve acoustic levels up to 3 dB higher
  • the membrane deflection is gripping Sensor, in particular an ultrasonic or a laser distance sensor, the measured over the measurement period of at least one oscillation period Integrated distance.
  • the sensor can be on the front as well also be arranged on the back of the membrane. In the latter case it is conceivable that the distance measurement through a hole in the pole core of the speaker through it.
  • a control voltage can be set with the aid of the distance signal generate that from the deviation of the membrane from its original Middle position or depending on their optimal working point.
  • the senor is at least one arranged in the effective range of the magnetic field and with the voice coil motion-coupled induction coil formed.
  • Two induction coils are preferred present together with the voice coil on one Voice coil former with an axial distance to each other and with respect to the center of the coil are arranged symmetrically.
  • diaphragms average the same voltages over time induced. If the working point shifts away from the optimal position, so the mean voltage in one of the two coils will rise in the other against it sink. The difference between the two voltages can then be used as a controlled variable for the correction voltage.
  • a loudspeaker is the one described Kind used in an active silencer.
  • the available space is often very narrow, so that the Size of a speaker is also narrowly limited. To make matters worse, that very high sound pressure levels have to be generated to reduce the exhaust sound the engine effectively.
  • a proposed Loudspeaker can be built in with a small size of the loudspeaker Generate high level anti-sound.
  • the loudspeaker shown in FIGS. 1 and 2 comprises a loudspeaker basket 1, which consists, for example, of metal, a funnel-shaped membrane 2, an annular magnet 3 arranged at the narrowed end of the loudspeaker basket 1, a pole core 4 arranged in the center of the magnet 3, one between permanent magnet 3 and loudspeaker basket 1 arranged pole plate 5 and a voice coil 6.
  • the voice coil 6 is wound on a substantially tubular tubular voice coil support 7, which is connected on the one hand to the membrane 2 and with its other end in an annular gap 8 between the permanent magnet 3 and the pole core 4 extends into it.
  • a centering element 9 is fixed, which surrounds the voice coil support 7 in a collar shape, is folded like an accordion and is fixed with its outer edge to the speaker basket 1.
  • a control device which comprises a sensor 10 which detects the membrane deflection and is arranged within the space spanned by the membrane 2.
  • the sensor 10 can, for example, be fixed to the edge region 11 of the loudspeaker basket 1 via a (not shown) carrier.
  • the sensor 10 in FIGS. 1 and 2 emits a laser beam 12 or an ultrasound signal, which is reflected on the front side 13 of the membrane and is evaluated by the sensor 10. For this purpose, the distance values of an oscillation period are integrated and an average value is determined.
  • the deviation of the membrane 2 or the voice coil 6 coupled to it via the carrier 7 from its optimal central position can thus be determined exactly.
  • the membrane swings around the central position X 0 to its end positions X 1 and -X 1 .
  • a shift in the central position in the direction of X 1 or -X 1 is detected by the sensor.
  • the control device of the voice coil 6 applies a direct current signal which is polarized positively or negatively depending on the direction of the position shift.
  • the resulting magnetic field interacts with the magnetic field 14 extending from the pole plate to the pole core 4, as a result of which the coil and thus the membrane 2 are moved into the optimal central position X 0 .
  • the magnetic field 14 weakening in its edge regions 15, 16 is represented by a smaller number of dashed lines.
  • the edge regions 15, 16 of a commercially available loudspeaker are usually asymmetrical, that is to say, at higher load levels, the voice coil 6 is increasingly immersed in the edge regions, the imbalance between the field strength of the edge regions 15, 16 therefore becoming more apparent than in the direction -X 1 or X 1 acting on the membrane 2 and shifting it from its central position X 0 force component is noticeable. Middle layer deviations can also be due to manufacturing inaccuracies.
  • FIG. 3 A further embodiment of a sensor 10a is shown in FIG. 3. It is composed here of two induction coils 17, 18, for example consisting of only one winding. These are wound on the voice coil support 7 at an axial distance from one another. The voice coil 5 is located between them. With respect to the center 19 of the voice coil 5, the induction coils 17, 18 are arranged symmetrically, that is to say they are each at the same distance from the voice coil center 19. If the induction coils move in a homogeneous magnetic field, the same voltage conditions are present at any point in time of a periodic oscillation of the carrier 7. An inhomogeneity of the magnetic field is noticeable through different voltages that can be recognized with suitable measuring devices. The size of the voltage difference between the induction coils 17, 18 is a measure of the deviation of the membrane from the optimal oscillation medium position X 0 .
  • An exhaust gas silencer 20 is shown schematically in FIG. 4. It has a housing 21, which is penetrated by an exhaust pipe 22.
  • the exhaust pipe is in Exhaust gas can flow through in the direction of arrow 23.
  • Near exit 24 is a sound coupling point 25 in the wall of the exhaust pipe 22, for example in the form of a perforation.
  • Via the sound coupling point 25 the exhaust pipe 24 is connected to the interior 26 of the exhaust silencer.
  • a loudspeaker on the side opposite the sound coupling point 25 27 arranged, which is designed according to the above statements is.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Silencers (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)

Abstract

Ein elektrodynamischer Lautsprecher mit einem ein Magnetfeld (14) erzeugenden Magneten (3), einer Schwingspule (6) und einer um eine Mittellage schwingenden Membran (2) weist eine Regeleinrichtung auf, mit der eine Mittellagen-Abweichung der Membran (2) mit Hilfe eines Sensors (10) detektierbar und die Schwingspule (6) mit einer der Abweichung entgegenwirkenden Gleichspannung beaufschlagbar ist. <IMAGE>An electrodynamic loudspeaker with a magnet (3) generating a magnetic field (14), a voice coil (6) and a membrane (2) vibrating around a central position has a control device with which a central position deviation of the membrane (2) can be determined with the aid of a Sensor (10) is detectable and the voice coil (6) can be acted upon with a DC voltage counteracting the deviation. <IMAGE>

Description

Die Erfindung betrifft einen elektrodynamischen Lautsprecher, insbesondere für einen aktiven Schalldämpfer eines Kraftfahrzeuges. Bei Lautsprechern der in Rede stehenden Art wird eine Membran über eine Schwingspule aus ihrer Mittellage periodisch abgelenkt. Zum Antrieb der Schwingspule ist ein Magnetfeld vorhanden, das von einem ringförmigen Magneten mit zentral darin angeordnetem Polkern sowie einer an der Membran zugewandten Stirnseite des Magneten angeordneten Polplatte erzeugt wird. Das sich mit seinen Feldlinien im Wesentlichen rechtwinklig zur Bewegungsrichtung der Schwingspule erstreckende Magnetfeld ist nun nicht vollkommen homogen sondern schwächt sich zu seinen in positiver oder negativer Auslenkungsrichtung weisenden Randbereichen hin. Im Idealfall ist das Magnetfeld völlig symmetrisch, so dass die darin in Axialrichtung periodisch oszillierende Schwingspule in positiver und negativer Auslenkungsrichtung stets mit der selben Kraft beaufschlagt wird. Bei einer Unsymmetrie des Magnetfelds hauptsächlich in diesen Randbereichen wird dagegen die Membran zusätzlich mit einer einseitig, etwa in positiver Auslenkungsrichtung wirkenden Kraftkomponente beaufschlagt und dementsprechend die Mittellage der mit der Schwingungsspule gekoppelten Membran entsprechend verschoben. Bei kleinen Schwingungsamplituden ist dieser Effekt praktisch vernachlässigbar. Je mehr jedoch die Schwingungsamplituden zunehmen, desto stärker bewirkt der beschriebene Effekt eine Verringerung des Wirkungsgrades des Lautsprechers. Wird zur Kompensation das Lautsprecher-Eingangssignal weiter erhöht, verschiebt sich die Membranmittellage um so mehr. Dies ist ein Nachteil insbesondere bei solchen Lautsprechern, die bedingt durch den zur Verfügung stehenden Einbauraum kleine Abmessungen aufweisen und dennoch hohe Leistungen bringen sollen, wie dies z.B. bei Antischalllautsprechern von aktiven Abgasschalldämpfern der Fall ist. The invention relates to an electrodynamic loudspeaker, in particular for an active silencer of a motor vehicle. Speakers of the in question standing type is a membrane over a voice coil from its central position periodically distracted. There is a magnetic field to drive the voice coil that of an annular magnet with a pole core arranged centrally in it and an end face of the magnet facing the membrane Pole plate is generated. That with its field lines essentially magnetic field extending at right angles to the direction of movement of the voice coil is not completely homogeneous now, but is weakening in a more positive way or edge regions pointing in a negative direction of deflection. Ideally it is the magnetic field is completely symmetrical, so that it is periodic in the axial direction oscillating voice coil in positive and negative deflection direction always is applied with the same force. With an asymmetry of the magnetic field In contrast, the membrane is additionally included mainly in these marginal areas a one-sided force component acting approximately in the positive direction of deflection acted upon and accordingly the middle position of the with the voice coil coupled membrane shifted accordingly. With small vibration amplitudes this effect is practically negligible. However, the more the vibration amplitudes increase, the stronger the effect described causes Reduction of the efficiency of the speaker. Becomes compensation If the loudspeaker input signal increases further, the diaphragm middle position shifts even more. This is a disadvantage especially with such speakers, the small dimensions due to the available installation space should have high performance, such as this for anti-noise speakers of active exhaust silencers is the case.

Aufgabe der Erfindung ist es, einen hinsichtlich seines Wirkungsgrades vor allen Dingen im höheren Leistungbereich verbesserten Lautsprecher vorzuschlagen.The object of the invention is one in terms of its efficiency above all To propose things in the higher power range to improved speakers.

Diese Aufgabe wird dadurch gelöst, dass eine Regeleinrichtung vorgesehen ist, mit der eine Mittellagen-Abweichung der Membran mit Hilfe eines Sensors detektierbar und die Schwingspule mit einer der Abweichung entgegenwirkenden Gleichspannung beaufschlagbar ist. Mit einer solchen Regeleinrichtung kann also erkannt werden, dass sich die Mittellage der Lautsprechermembran in einen kritischen Bereich verschoben hat. Je nach Verschiebung in positiver oder negativer Auslenkungsrichtung wird eine entsprechend gepolte, das Ansteuersignal überlagernde Korrekturspannung an die Schwingspule angelegt, wodurch die Membran in ihre Ausgangsmittellage zurückgeführt wird. Bei einem derart ausgestalteten Lautsprecher lassen sich beispielsweise bis zu 3 dB höhere akustische Pegel erzielenThis object is achieved in that a control device is provided with which a middle layer deviation of the membrane can be detected with the aid of a sensor and the voice coil with one counteracting the deviation DC voltage can be applied. So with such a control device can be recognized that the center position of the speaker membrane in a critical Area has moved. Depending on the shift in positive or negative The direction of deflection becomes a correspondingly polarized one which overlaps the control signal Correction voltage applied to the voice coil, causing the diaphragm is returned to its starting position. With such a design For example, speakers can achieve acoustic levels up to 3 dB higher

Bei einer bevorzugten Ausgestaltung ist ein die Membranauslenkung abgreifender Sensor, insbesondere ein Ultraschall- oder ein Laser- Abstandssensor vorhanden, der über den Meßzeitraum von wenigstens einer Schwingungsperiode den gemessenen Abstand integriert. Der Sensor kann sowohl auf der Vorderseite als auch auf der Rückseite der Membran angeordnet sein. Im letztgenannten Fall ist es denkbar, dass die Abstandsmessung durch eine Bohrung im Polkern des Lautsprechers hindurch erfolgt. Mit Hilfe des Abstandssignals lässt sich eine Steuerspannung generieren, die von der Abweichung der Membran von ihrer ursprünglichen Mittellage bzw. von ihrem optimalen Arbeitspunkt abhängig ist.In a preferred embodiment, the membrane deflection is gripping Sensor, in particular an ultrasonic or a laser distance sensor, the measured over the measurement period of at least one oscillation period Integrated distance. The sensor can be on the front as well also be arranged on the back of the membrane. In the latter case it is conceivable that the distance measurement through a hole in the pole core of the speaker through it. A control voltage can be set with the aid of the distance signal generate that from the deviation of the membrane from its original Middle position or depending on their optimal working point.

Bei einer weiteren bevorzugten Ausgestaltung ist der Sensor von wenigstens einer im Wirkungsbereich des Magnetfeldes angeordneten und mit der Schwingspule bewegungsgekoppelten Induktionsspule gebildet. Bevorzugterweise sind zwei Induktionsspulen vorhanden, die gemeinsam mit der Schwingspule auf einem Schwingspulenträger mit Axialabstand zueinander und bezüglich der Spulenmitte symmetrisch angeordnet sind. Bei um den idealen Arbeitspunkt schwingender Membran werden in beiden Spulen im zeitlichen Mittel jeweils gleich große Spannungen induziert. Verschiebt sich der Arbeitspunkt von der optimalen Lage weg, so wird die mittlere Spannung in einer der beiden Spulen ansteigen in der anderen dagegen absinken. Die Differenz der beiden Spannungen läßt sich dann als Regelgröße für die Korrekturspannung hernehmen.In a further preferred embodiment, the sensor is at least one arranged in the effective range of the magnetic field and with the voice coil motion-coupled induction coil formed. Two induction coils are preferred present together with the voice coil on one Voice coil former with an axial distance to each other and with respect to the center of the coil are arranged symmetrically. When swinging around the ideal working point In both coils, diaphragms average the same voltages over time induced. If the working point shifts away from the optimal position, so the mean voltage in one of the two coils will rise in the other against it sink. The difference between the two voltages can then be used as a controlled variable for the correction voltage.

Bei einer besonders bevorzugten Verwendung wird ein Lautsprecher der geschilderten Art in einem aktiven Schalldämpfer eingesetzt. Bei solchen Schalldämpfern ist oft der zur Verfügung stehende Bauraum sehr eng bemessen, so dass die Baugröße eines Lautsprechers ebenfalls eng begrenzt ist. Erschwerend hinzukommt, dass sehr hohe Schalldruckpegel erzeugt werden müssen, um den Abgasschall des Motors wirksam zu bekämpfen. Durch den Einbau eines vorgeschlagenen Lautsprechers läßt sich bei geringer Baugröße des Lautsprechers ein Antischall mit hohem Pegel erzeugen.In a particularly preferred use, a loudspeaker is the one described Kind used in an active silencer. With such silencers the available space is often very narrow, so that the Size of a speaker is also narrowly limited. To make matters worse, that very high sound pressure levels have to be generated to reduce the exhaust sound the engine effectively. By installing a proposed Loudspeaker can be built in with a small size of the loudspeaker Generate high level anti-sound.

Die Erfindung wird nun anhand von in den beigefügten Zeichnungen dargestellten Ausführungsbeispielen näher erläutert. Es zeigen:

Fig.1
einen elektrodynamischen Lautsprecher in Querschnittdarstellung,
Fig.2
einen vergrößerten Ausschnitt aus Fig. 1,
Fig.3
eine schematische Seitenansicht eines Schwingspulenträgers mit einer Schwingspule und zwei Induktionsspulen, wobei letztere einen Sensor für die Auslenkung der Lautsprechermembran bilden,
Fig.4
eine schematische Darstellung eines Abgasschalldämpfers mit einem Antischalllautsprecher.
The invention will now be explained in more detail with reference to exemplary embodiments illustrated in the accompanying drawings. Show it:
Fig. 1
an electrodynamic loudspeaker in cross section,
Fig. 2
2 shows an enlarged detail from FIG. 1,
Fig. 3
2 shows a schematic side view of a voice coil carrier with a voice coil and two induction coils, the latter forming a sensor for the deflection of the loudspeaker membrane,
Fig. 4
is a schematic representation of an exhaust silencer with an anti-noise speaker.

Der in Fig.1 und 2 dargestellte Lautsprecher umfasst einen Lautsprecherkorb 1, der z.B. aus Metall besteht, einer trichterförmigen Membran 2, einem am verengten Ende des Lautsprecherkorbs 1 angeordneten ringförmigen Magneten 3, einem im Zentrum des Magneten 3 angeordneten Polkern 4, einer zwischen Dauermagnet 3 und Lautsprecherkorb 1 angeordneten Polplatte 5 sowie einer Schwingspule 6. Die Schwingspule 6 ist auf einem im Wesentlichen rohrabschnittförmigen Schwingspulenträger 7 aufgewickelt, der einerseits mit der Membran 2 verbunden ist und der sich mit seinem anderen Ende in einen ringförmigen Spaltraum 8 zwischen Dauermagnet 3 und Polkern 4 hinein erstreckt. Am Übergangsbereich zwischen Schwingspulenträger 7 und Membran 2 ist ein Zentrierelement 9 fixiert, dass den Schwingspulenträger 7 kragenförmig umgibt, ziehharmonikaartig gefaltet und mit seinem äußeren Rand am Lautsprecherkorb 1 fixiert ist. Weiterhin ist eine Regeleinrichtung vorhanden, die einen innerhalb des von der Membran 2 umspannten Raumes angeordneten, die Membranauslenkung detektierenden Sensor 10 umfasst. Der Sensor 10 kann z.B. über einen (nichtdargestellten Träger) am Randbereich 11 des Lautsprecherkorbs 1 fixiert sein. Der Sensor 10 in Fig. 1 und Fig. 2 sendet einen Laserstrahl 12 oder ein Ultraschallsignal aus, das an der Membranvorderseite 13 reflektiert und vom Sensor 10 ausgewertet wird. Dazu werden die Abstandswerte einer Schwingungsperiode integriert und ein Durchschnittswert ermittelt. Die Abweichung der Membran 2 bzw. der mit ihr über den Träger 7 gekoppelten Schwingspule 6 von ihrer optimalen Mittellage lässt sich damit exakt bestimmen. Im Idealfall schwingt die Membran um die Mittellage X0 bis in ihre Endlagen X1 und -X1. Eine Verschiebung der Mittellage in Richtung X1 oder -X1 wird vom Sensor detektiert. Zur Kompensierung der Mittellagenverschiebung der Membran 2 schaltet die Regeleinrichtung der Schwingspule 6 ein Gleichstromsignal auf, das je nach Richtung der Mittellagenverschiebung positiv oder negativ gepolt ist. Das dadurch entstehende Magnetfeld tritt mit dem sich von der Polplatte zum Polkern 4 erstreckenden Magnetfeld 14 in Wechselwirkung, wodurch die Spule und damit die Membran 2 in die optimale Mittellage X0 bewegt wird. In Fig.2 ist das sich in seinen Randbereichen 15, 16 abschwächende Magnetfeld 14 durch eine geringere Anzahl von strichlierten Linien dargestellt. Die Randbereiche 15, 16 eines handelsüblichen Lautsprechers sind gewöhnlicherweise unsymmetrisch, das heißt bei höheren Belastungspegeln taucht die Schwingspule 6 zunehmend mehr in die Randbereiche ein, das Ungleichgewicht zwischen der Feldstärke der Randbereiche 15, 16 macht sich daher zusehends als in Richtung -X1 bzw. X1 auf die Membran 2 wirkende und sie aus ihrer Mittellage X0 verschiebende Kraftkomponente bemerkbar. Mittellagenabweichungen können auch auf Fertigungsungenauigkeiten zurückgehen. The loudspeaker shown in FIGS. 1 and 2 comprises a loudspeaker basket 1, which consists, for example, of metal, a funnel-shaped membrane 2, an annular magnet 3 arranged at the narrowed end of the loudspeaker basket 1, a pole core 4 arranged in the center of the magnet 3, one between permanent magnet 3 and loudspeaker basket 1 arranged pole plate 5 and a voice coil 6. The voice coil 6 is wound on a substantially tubular tubular voice coil support 7, which is connected on the one hand to the membrane 2 and with its other end in an annular gap 8 between the permanent magnet 3 and the pole core 4 extends into it. At the transition area between voice coil support 7 and membrane 2, a centering element 9 is fixed, which surrounds the voice coil support 7 in a collar shape, is folded like an accordion and is fixed with its outer edge to the speaker basket 1. Furthermore, there is a control device which comprises a sensor 10 which detects the membrane deflection and is arranged within the space spanned by the membrane 2. The sensor 10 can, for example, be fixed to the edge region 11 of the loudspeaker basket 1 via a (not shown) carrier. The sensor 10 in FIGS. 1 and 2 emits a laser beam 12 or an ultrasound signal, which is reflected on the front side 13 of the membrane and is evaluated by the sensor 10. For this purpose, the distance values of an oscillation period are integrated and an average value is determined. The deviation of the membrane 2 or the voice coil 6 coupled to it via the carrier 7 from its optimal central position can thus be determined exactly. Ideally, the membrane swings around the central position X 0 to its end positions X 1 and -X 1 . A shift in the central position in the direction of X 1 or -X 1 is detected by the sensor. To compensate for the shift in the center position of the membrane 2, the control device of the voice coil 6 applies a direct current signal which is polarized positively or negatively depending on the direction of the position shift. The resulting magnetic field interacts with the magnetic field 14 extending from the pole plate to the pole core 4, as a result of which the coil and thus the membrane 2 are moved into the optimal central position X 0 . 2, the magnetic field 14 weakening in its edge regions 15, 16 is represented by a smaller number of dashed lines. The edge regions 15, 16 of a commercially available loudspeaker are usually asymmetrical, that is to say, at higher load levels, the voice coil 6 is increasingly immersed in the edge regions, the imbalance between the field strength of the edge regions 15, 16 therefore becoming more apparent than in the direction -X 1 or X 1 acting on the membrane 2 and shifting it from its central position X 0 force component is noticeable. Middle layer deviations can also be due to manufacturing inaccuracies.

In Fig. 3 ist eine weitere Ausgestaltung eines Sensors 10a gezeigt. Er setzt sich hier aus zwei beispielsweise nur aus einer Wicklung bestehenden Induktionsspulen 17, 18 zusammen. Diese sind mit Axialabstand zueinander auf dem Schwingungsspulenträger 7 aufgewickelt. Zwischen ihnen befindet sich die Schwingspule 5. Bezüglich der Mitte 19 der Schwingspule 5 sind die Induktionsspulen 17, 18 symmetrisch angeordnet, weisen also jeweils den gleichen Abstand zur Schwingspulenmitte 19 auf. Wenn sich die Induktionsspulen in einem homogenen Magnetfeld bewegen, sind in jedem Zeitpunkt einer periodischen Schwingung des Trägers 7 gleiche Spannungsverhältnisse vorhanden. Eine Inhomogenität des Magnetfeldes macht sich durch unterschiedliche Spannungen bemerkbar, die mit geeigneten Meßgeräten erkennbar sind. Die Größe der Spannungsdifferenz zwischen den Induktionsspulen 17, 18 ist ein Mass für die Abweichung der Membran von der optimalen Schwingungsmittellage X0.A further embodiment of a sensor 10a is shown in FIG. 3. It is composed here of two induction coils 17, 18, for example consisting of only one winding. These are wound on the voice coil support 7 at an axial distance from one another. The voice coil 5 is located between them. With respect to the center 19 of the voice coil 5, the induction coils 17, 18 are arranged symmetrically, that is to say they are each at the same distance from the voice coil center 19. If the induction coils move in a homogeneous magnetic field, the same voltage conditions are present at any point in time of a periodic oscillation of the carrier 7. An inhomogeneity of the magnetic field is noticeable through different voltages that can be recognized with suitable measuring devices. The size of the voltage difference between the induction coils 17, 18 is a measure of the deviation of the membrane from the optimal oscillation medium position X 0 .

In Fig. 4 ist ein Abgasschalldämpfer 20 schematisch dargestellt. Er weist ein Gehäuse 21 auf, das von einem Abgasrohr 22 durchsetzt ist. Das Abgasrohr ist in Richtung des Pfeiles 23 von Abgas durchströmbar. In der Nähe des Ausgangs 24 ist in der Wandung des Abgasrohres 22 eine Schallkopplungsstelle 25 beispielsweise in Form einer Perforierung vorhanden. Über die Schallkopplungsstelle 25 ist das Abgasrohr 24 mit dem Innenraum 26 des Abgasschalldämpfers verbunden. In diesem ist an der Schallkopplungsstelle 25 gegenüberliegenden Seite ein Lautsprecher 27 angeordnet, der entsprechend den obigen Ausführungen ausgestaltet ist. An exhaust gas silencer 20 is shown schematically in FIG. 4. It has a housing 21, which is penetrated by an exhaust pipe 22. The exhaust pipe is in Exhaust gas can flow through in the direction of arrow 23. Near exit 24 is a sound coupling point 25 in the wall of the exhaust pipe 22, for example in the form of a perforation. Via the sound coupling point 25 the exhaust pipe 24 is connected to the interior 26 of the exhaust silencer. In this is a loudspeaker on the side opposite the sound coupling point 25 27 arranged, which is designed according to the above statements is.

BezugszeichenlisteReference list

11
LautsprecherkorbSpeaker basket
22nd
Membranmembrane
33rd
Magnetmagnet
44th
PolkernPolkern
55
PolplattePole plate
66
SchwingspuleVoice coil
77
Trägercarrier
88th
SpaltraumGap
99
ZentrierelementCentering element
1010th
Sensorsensor
1111
RandbereichEdge area
1212th
Laserstrahllaser beam
1313
MembranvorderseiteMembrane front
1414
MagnetfeldMagnetic field
1515
RandbereichEdge area
1616
RandbereichEdge area
1717th
InduktionsspuleInduction coil
1818th
InduktionsspuleInduction coil
1919th
SpulenmitteCoil center
2020th
AbgasschalldämpferExhaust silencer
2121
Gehäusecasing
2222
AbgasrohrExhaust pipe
2323
Pfeilarrow
2424th
Ausgangoutput
2525th
SchallkopplungsstelleSound coupling point
2626
Innenrauminner space
2727
Lautsprecherspeaker

Claims (7)

Elektrodynamischer Lautsprecher, mit einem ein Magnetfeld (14) erzeugenden Magneten (13), einer Schwingspule (6) und einer um eine Mittellage schwingenden Membran (2),
   gekennzeichnet durch,
eine Regeteinrichtung, mit der eine Mittellagen-Abweichung der Membran (2) mit Hilfe eines Sensors (10) detektierbar und die Schwingspute (6) mit einer der Abweichung entgegenwirkenden Gleichspannung beaufschlagbar ist.Electrodynamic loudspeaker, with a magnet (13) generating a magnetic field (14), a voice coil (6) and a membrane (2) vibrating around a central position,
marked by,
a regulating device with which a deviation of the middle position of the membrane (2) can be detected with the aid of a sensor (10) and the oscillating turkey (6) can be acted upon by a direct voltage which counteracts the deviation. Lautsprecher nach Anspruch 1
   gekennzeichnet durch
einen die Membranauslenkung detektierenden Sensor (10).A loudspeaker according to claim 1
marked by
a sensor (10) detecting the membrane deflection. Lautsprecher nach Anspruch 2,
   gekennzeichnet durch
einen Ultraschallsensor.Loudspeaker according to claim 2,
marked by
an ultrasonic sensor. Lautsprecher nach Anspruch 2,
   gekennzeichnet durch
einen Lasersensor.Loudspeaker according to claim 2,
marked by
a laser sensor. Lautsprecher nach Anspruch 1,
   dadurch gekennzeichnet,
dass der Sensor (10a) aus wenigstens einer im Wirkungsbereich des Magneten (13) angeordneten und mit der Schwingspule (6) bewegungsgekoppelten Induktionsspule (17) gebildet ist.A loudspeaker according to claim 1,
characterized,
that the sensor (10a) is formed from at least one induction coil (17) which is arranged in the effective range of the magnet (13) and is motion-coupled to the voice coil (6). Lautsprecher nach Anspruch 5
   gekennzeichnet durch
zwei Induktionsspulen (17, 18), die gemeinsam mit der Schwingspule (6) auf einem Schwingungsspulenträger (7) und bezüglich der Spulenmitte (19) symmetrisch angeordnet sind.A loudspeaker according to claim 5
marked by
two induction coils (17, 18), which are arranged symmetrically together with the voice coil (6) on a voice coil support (7) and with respect to the coil center (19). Verwendung eines Lautsprechers nach einem der Ansprüche 1 bis 6 für den aktiven Schalldämpfer eines Kraftfahrzeuges.Use of a loudspeaker according to one of claims 1 to 6 for the active silencer of a motor vehicle.
EP00110585A 1999-05-19 2000-05-18 Electrodynamic loudspeaker with a control device for an active vehicle noice attenuator Withdrawn EP1059830A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19922897 1999-05-19
DE19922897 1999-05-19

Publications (2)

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EP1059830A3 EP1059830A3 (en) 2003-12-17

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EP00110585A Withdrawn EP1059830A3 (en) 1999-05-19 2000-05-18 Electrodynamic loudspeaker with a control device for an active vehicle noice attenuator
EP00110736A Expired - Lifetime EP1055804B1 (en) 1999-05-19 2000-05-19 Active exhaust silencer

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP00110736A Expired - Lifetime EP1055804B1 (en) 1999-05-19 2000-05-19 Active exhaust silencer

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EP (2) EP1059830A3 (en)
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102012005893A1 (en) * 2012-03-23 2013-09-26 Audi Ag Method for operating a loudspeaker device, loudspeaker device and device for noise compensation
US10701477B2 (en) 2018-03-27 2020-06-30 Sony Corporation Loudspeaker, acoustic waveguide, and method
US11012788B2 (en) 2018-03-27 2021-05-18 Sony Corporation Loudspeaker system
CN113153493A (en) * 2021-04-26 2021-07-23 吉林大学 Exhaust silencer for internal combustion engine

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004040421A1 (en) 2004-08-19 2006-03-09 J. Eberspächer GmbH & Co. KG Active exhaust silencer
DE102006042224B3 (en) * 2006-09-06 2008-01-17 J. Eberspächer GmbH & Co. KG Active sound absorber for exhaust-gas system of internal-combustion engine particularly in motor vehicle, has anti sound generator comprises membrane drive, with which anti sound generator is coupled with external wall of sound absorber
DE102008018085A1 (en) 2008-04-09 2009-10-15 J. Eberspächer GmbH & Co. KG Active muffler
DE102009049280B4 (en) 2009-10-13 2016-10-06 Eberspächer Exhaust Technology GmbH & Co. KG Active muffler
EP2530263B1 (en) 2011-06-01 2013-08-21 Eberspächer Exhaust Technology GmbH & Co. KG Active noise control system for exhaust systems and method for controlling the same
DE102011106647A1 (en) 2011-07-05 2013-01-10 J. Eberspächer GmbH & Co. KG ANTISCHALL SYSTEM FOR EXHAUST SYSTEMS AND METHOD FOR CONTROLLING THE SAME
DE102011117495B4 (en) 2011-11-02 2014-08-21 Eberspächer Exhaust Technology GmbH & Co. KG Overload protection for loudspeakers in exhaust systems
DE102011117807A1 (en) * 2011-11-07 2013-05-08 Friedrich Boysen Gmbh & Co. Kg Sound damping device for gas-guiding pipe, particularly for exhaust pipe of exhaust gas system of motor vehicle, has vibratory membrane, which stays in acoustic connection with gas-guiding pipe at coupling-out point
JP5681691B2 (en) 2011-12-02 2015-03-11 エーバーシュペッヒャー・エグゾースト・テクノロジー・ゲーエムベーハー・ウント・コンパニー・カーゲー Active design of exhaust noise
DE102011089774B4 (en) * 2011-12-23 2014-03-27 Eberspächer Exhaust Technology GmbH & Co. KG exhaust system
DE102012109872B4 (en) 2012-10-16 2015-08-27 Eberspächer Exhaust Technology GmbH & Co. KG Speakers with improved thermal capacity
DE102013104307A1 (en) 2013-04-26 2014-10-30 Eberspächer Exhaust Technology GmbH & Co. KG System for influencing exhaust noise and / or intake noise and / or engine noise
EP2797075B1 (en) 2013-04-26 2018-09-12 Eberspächer Exhaust Technology GmbH & Co. KG System for influencing exhaust noise, engine noise and/or intake noise
DE102013208186B4 (en) * 2013-05-03 2016-09-22 Eberspächer Exhaust Technology GmbH & Co. KG Sound generator for an exhaust system
DE102013104810A1 (en) 2013-05-08 2014-11-13 Eberspächer Exhaust Technology GmbH & Co. KG VEHICLE GENERATOR FOR AN ANTI-VALL SYSTEM FOR INFLUENCING EXHAUST VACUUM AND / OR INTAKE NOISE OF A MOTOR VEHICLE
DE102013010609B4 (en) 2013-06-25 2023-07-27 Purem GmbH System for influencing exhaust noise in a multi-flow exhaust system and motor vehicle
DE102013011937B3 (en) 2013-07-17 2014-10-09 Eberspächer Exhaust Technology GmbH & Co. KG Sound generator for an anti-noise system for influencing exhaust noise and / or Ansauggeräuschen a motor vehicle
DE102013217849A1 (en) * 2013-09-06 2015-03-12 Friedrich Boysen Gmbh & Co. Kg Active sound generating device
JP2015172370A (en) 2014-03-04 2015-10-01 エーバーシュペッヒャー・エグゾースト・テクノロジー・ゲーエムベーハー・ウント・コンパニー・カーゲー active design of exhaust sound
DE102015119191A1 (en) 2015-11-06 2017-05-11 Eberspächer Exhaust Technology GmbH & Co. KG Sound generator for attachment to a vehicle for influencing noises of the vehicle
DE102018109529B4 (en) * 2018-04-20 2019-11-28 Tenneco Gmbh Retaining flange for metering valve

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3014096A (en) * 1956-05-29 1961-12-19 Warner W Clements Sound reproducing means
US4243839A (en) * 1977-12-14 1981-01-06 Matsushita Electric Industrial Co., Ltd. Transducer with flux sensing coils
GB2083974A (en) * 1980-09-04 1982-03-31 Rank Organisation The Ltd Moving coil loudspeaker
GB2196815A (en) * 1986-09-25 1988-05-05 David Robin Birt Motional feedback system for loudspeakers
US5541373A (en) * 1994-09-06 1996-07-30 Digisonix, Inc. Active exhaust silencer

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5044464A (en) * 1990-01-23 1991-09-03 Nelson Industries, Inc. Active acoustic attenuation mixing chamber
US5319165A (en) * 1990-04-25 1994-06-07 Ford Motor Company Dual bandpass secondary source
US5229556A (en) * 1990-04-25 1993-07-20 Ford Motor Company Internal ported band pass enclosure for sound cancellation
US5748749A (en) * 1993-03-24 1998-05-05 Noise Cancellation Technologies, Inc. Active noise cancelling muffler

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3014096A (en) * 1956-05-29 1961-12-19 Warner W Clements Sound reproducing means
US4243839A (en) * 1977-12-14 1981-01-06 Matsushita Electric Industrial Co., Ltd. Transducer with flux sensing coils
GB2083974A (en) * 1980-09-04 1982-03-31 Rank Organisation The Ltd Moving coil loudspeaker
GB2196815A (en) * 1986-09-25 1988-05-05 David Robin Birt Motional feedback system for loudspeakers
US5541373A (en) * 1994-09-06 1996-07-30 Digisonix, Inc. Active exhaust silencer

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102012005893A1 (en) * 2012-03-23 2013-09-26 Audi Ag Method for operating a loudspeaker device, loudspeaker device and device for noise compensation
US10701477B2 (en) 2018-03-27 2020-06-30 Sony Corporation Loudspeaker, acoustic waveguide, and method
US11012788B2 (en) 2018-03-27 2021-05-18 Sony Corporation Loudspeaker system
CN113153493A (en) * 2021-04-26 2021-07-23 吉林大学 Exhaust silencer for internal combustion engine

Also Published As

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EP1055804A1 (en) 2000-11-29
EP1055804B1 (en) 2003-03-12
EP1059830A3 (en) 2003-12-17
DE50001427D1 (en) 2003-04-17

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