DE3106029A1 - Method and arrangement for reducing the noise level in the head region of motor vehicle occupants - Google Patents

Method and arrangement for reducing the noise level in the head region of motor vehicle occupants

Info

Publication number
DE3106029A1
DE3106029A1 DE19813106029 DE3106029A DE3106029A1 DE 3106029 A1 DE3106029 A1 DE 3106029A1 DE 19813106029 DE19813106029 DE 19813106029 DE 3106029 A DE3106029 A DE 3106029A DE 3106029 A1 DE3106029 A1 DE 3106029A1
Authority
DE
Germany
Prior art keywords
noise level
arrangement
motor vehicle
combustion engine
internal combustion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
DE19813106029
Other languages
German (de)
Inventor
Peter Dipl.-Ing. 3170 Gifhorn Seifert
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.)
Volkswagen AG
Original Assignee
Volkswagen AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Volkswagen AG filed Critical Volkswagen AG
Priority to DE19813106029 priority Critical patent/DE3106029A1/en
Publication of DE3106029A1 publication Critical patent/DE3106029A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17857—Geometric disposition, e.g. placement of microphones
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17879—General system configurations using both a reference signal and an error signal
    • G10K11/17883—General system configurations using both a reference signal and an error signal the reference signal being derived from a machine operating condition, e.g. engine RPM or vehicle speed
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/128—Vehicles
    • G10K2210/1282—Automobiles
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3045—Multiple acoustic inputs, single acoustic output
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/321—Physical
    • G10K2210/3225—Radio or other sources used in ANC for transfer function estimation; Means to avoid interference between desired signals, e.g. from a car stereo, and the ANC signal
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/50—Miscellaneous
    • G10K2210/511—Narrow band, e.g. implementations for single frequency cancellation

Abstract

In the method and the arrangement for reducing the noise level in the head region of motor vehicle occupants, a sinusoidal sound signal of equal intensity about one hundred and eighty degrees out of phase is superimposed on an especially disturbing frequency component in the noise level caused in the passenger compartment by the internal combustion engine of the vehicle. <IMAGE>

Description

Verfahren und Anordnung zur Verrinqerunq des Geräusch- Procedure and arrangement for reducing the noise

pegels im Kopfbereich von Kraftfahrzeuqinsassen Die Erfindung betrifft ein Verfahren und eine Anordnung gemäß dem Gattungsbegriff des Patentanspruchs 1. level in the head area of motor vehicle occupants The invention relates a method and an arrangement according to the preamble of claim 1.

Eine Vielzahl bekannter Verfahren und Anordnungen zur Verringerung des insbesondere von der Brennkraftmaschine eines Kraftfahrzeugs ausgehenden Geräuschpegels besteht darin, die durch die Maschine gebildete Geräuschquelle von der Fahrgastzelle und der Umgebung abzukapseln. Dies führt einerseits zu Schwierigkeiten infolge des vergrößerten Fahrzeuggewichts, der schweren Zugänglichkeit der Brennkraftmaschine sowie der erschwerten Kühlung derselben und ist andererseits hinsichtlich der Verminderung des Geräuschpegels im Kopfbereich der Fahrzeuginsassen begrenzt, da Schallbrücken nicht vollständig zu vermeiden sind. A variety of known methods and arrangements for reducing the noise level emanating in particular from the internal combustion engine of a motor vehicle is the source of noise generated by the machine from the passenger compartment and encapsulate the environment. On the one hand, this leads to difficulties as a result of the increased vehicle weight, the difficult accessibility of the internal combustion engine as well as the difficult cooling of the same and is on the other hand in terms of reduction the noise level in the head area of the vehicle occupants is limited, as sound bridges cannot be completely avoided.

Für einen Sonderfall, nämlich den Betrieb eines Rundfunkgeräts in einem Kraftfahrzeug, ist es beispielsweise aus der DE-OS 23 10 562, H03g 3/20, bekannt, den Lautsprecher mit einer in Abhängigkeit vom Schallpegel in der Fahrgastzelle arbeitenden Lautstärkenregelung zu versehen, so daß bei einem hohen Geräuschpegel in der Fahrgastzelle die Lautstärke des Lautsprechers vergrößert wird. For a special case, namely the operation of a radio in a motor vehicle, it is known for example from DE-OS 23 10 562, H03g 3/20, the loudspeaker with one depending on the sound level in the passenger compartment working volume control, so that at a high noise level the loudspeaker volume is increased in the passenger compartment.

Diese elektroakustische Berücksichtigung des jeweiligen Geräuschpegels in dem Fahrgastraum nimmt aber den störenden Geräuschpegel als solchen in Kauf und regelt lediglich bei Betrieb des Lautsprechers dessen Lautstärke im Hinblick auf den störenden Geräuschpegel.This electroacoustic consideration of the respective noise level in the passenger compartment, however, accepts the disturbing noise level as such and only regulates the volume of the loudspeaker when it is in operation the annoying noise level.

Der Erfindung liegt demgegenüber die Aufgabe zugrunde, ein Verfahren gemäß dem Gattungsbegriff des Patentanspruchs 1 sowie eine Anordnung zur Durchführung dieses Verfahrens zu schaffen, d.h. ein Verfahren und eine Anordnung, die den störenden Geräuschpegel selber verringern.In contrast, the invention is based on the object of a method according to the generic term of claim 1 and an arrangement for implementation to create this method, i.e. a method and an arrangement that eliminates the interfering Reduce the noise level yourself.

Die erfindungsgemäße Lösung dieser Aufgabe besteht in den kennzeichnenden Merkmalen des Patentanspruchs 1; vorteilhafte Ausgestaltungen einer Anordnung zur Durchführung des Verfahrens sind Gegenstand der Unteransprüche.The inventive solution to this problem consists in the characterizing Features of claim 1; advantageous configurations of an arrangement for Implementation of the method are the subject of the subclaims.

Bei der Erfindung erfolgt also eine Überlagerung des Geräuschpegels mit sinusförmigen gegenphasigen Schallsignalen, deren Frequenz einer besonders störenden Frequenz im Geräuschpegel entspricht.In the invention, the noise level is superimposed with sinusoidal anti-phase sound signals, the frequency of which is a particularly disturbing one Frequency corresponds in the noise level.

Da gemäß Patentanspruch 5 der Lautsprecher zugleich einen Bestandteil eines ohnehin vorhandenen Rundfunkempfängers im Fahrzeug bilden kann, besitzt die Erfindung den weiteren Vorteil eines verhältnismäßig geringen Aufwands.Since, according to claim 5, the loudspeaker is also a component can form an already existing radio receiver in the vehicle, has the Invention has the further advantage of relatively little effort.

Im folgenden wird ein Ausführungsbeispiel der Erfindung anhand der Zeichnung erläutert, deren Fig. 1- das Blockschaltbild und deren Fig. 2 in einem Diagramm die Wirksamkeit einer erfindungsgemäßen Anordnung zeigen.In the following an embodiment of the invention is based on the Drawing explained, FIG. 1- the block diagram and FIG. 2 in one Diagram showing the effectiveness of an arrangement according to the invention.

An der Brennkraftmaschine 1 des Kraftfahrzeugs 2 werden Zündimpulse oder der Drehzahl der Kurbelwelle entsprechende Signale als Synchronisiersignale abgegriffen und dem Sinusgenerator 3 zugeführt, der Sinussignale mit dieser Frequenz an den Amplituden- und Phasenregler 4 liefert. An den Regeleingang des Reglers 4 ist das vorzugsweise im Kopfbereich des Fahrers, z.B. im Dachhimmel oder einer Nackenstütze, angeordnete Mikrofon 5 angeschlossen, das Signale für Amplitude und Phasenlage für diesen Frequenzanteil des Geräuschpegels im Fahrzeug 2 liefert. Das Ausgangssignal 6 des Reglers 4, das über den Leistungsverstärker 7 dem Lautsprecher 8 im Fahrzeug 2 zugeführt wird, ist demgemäß hinsichtlich Amplitude und Phase so eingestellt, daß dieser Frequenzanteil des Geräuschpegels im Kopfbereich der Fahrzeuginsassen und damit am Ort des Mikrofons 5 durch Überlagerung mit den vom Lautsprecher 8 gelieferten sinusförmigen Schallsignalen ein Minimum besitzt.Ignition pulses are applied to the internal combustion engine 1 of the motor vehicle 2 or signals corresponding to the speed of the crankshaft as synchronization signals tapped and fed to the sine generator 3, the sine signals with this frequency to the amplitude and phase regulator 4 supplies. To the control input of the controller 4 this is preferably in the head area of the driver, e.g. in the headliner or a neck rest, arranged microphone 5 connected, the signals for amplitude and phase position for this frequency component of the noise level in vehicle 2 supplies. The output signal 6 of the controller 4, which via the power amplifier 7 to the loudspeaker 8 in the vehicle 2 is supplied, is accordingly in terms of amplitude and phase set, that this frequency component of the noise level in the head area of the vehicle occupants and thus at the location of the microphone 5 by superimposing the information supplied by the loudspeaker 8 sinusoidal sound signals has a minimum.

Die Wirkung dieser Anordnung zeigt das Diagramm nach Fig. 2, in dem der Schallpegel L über der Drehzahl n der Brennkraftmaschine aufgetragen ist.The effect of this arrangement is shown in the diagram of FIG the sound level L is plotted against the speed n of the internal combustion engine.

Ohne die erfindungsgemäße Anordnung befolgt der Schallpegel über der Drehzahl einen Verlauf gemäß Kurve a mit ausgeprägten Maxima etwa im Bereich von 3000 und 4000 bis 5000 U/min. Bei Verwendung der erfindungsgemäßen Anordnung ergibt sich demgegenüber die Kurve b, die gerade bei diesen Drehzahlen eine erhebliche Verringerung des Schallpegels sicherstellt.Without the arrangement according to the invention, the sound level obeys above Speed has a course according to curve a with pronounced maxima approximately in the range of 3000 and 4000 to 5000 rpm. When using the arrangement according to the invention results In contrast, the curve b, which is a considerable especially at these speeds Ensures reduction of the sound level.

Claims (5)

Patentansprüche 1. Verfahren zur Verringerung des von einer periodisch arbeitenden Geräuschquelle, insbesondere einer Brennkraftmaschine, verursachten Geräuschpegels im Kopfbereich von Insassen eines Kraftfahrzeugs, dadurch gekennzeichnet, daß im Kopfbereich sinusförmige Schallsignale mit einer Frequenz, die einer störenden Frequenz im Geräuschpegel entspricht, mit gleicher Intensität, aber in Gegenphase zu den Geräuschen mit der störenden Frequenz erzeugt werden. Claims 1. A method for reducing the periodic working noise source, in particular an internal combustion engine Noise level in the head area of occupants of a motor vehicle, characterized in that that in the head area sinusoidal sound signals with a frequency that of a disruptive Frequency corresponds to the noise level, with the same intensity, but in opposite phase to the noises with the disturbing frequency are generated. 2. Anordnung zur Durchführung des Verfahrens nach Anspruch 1, dadurch gekennzeichnet, daß ein von der Geräuschquelle (1) synchronisierter Sinusgenerator (3) auf zumindest einen Lautsprecher (8) im Kraftfahrzeug (2) über einen Amplitude und Phasenregler (4) arbeitet, der mittels eines Mikrofons (5) geregelt wird.2. Arrangement for performing the method according to claim 1, characterized characterized in that a sine wave generator synchronized by the noise source (1) (3) on at least one loudspeaker (8) in the motor vehicle (2) via an amplitude and phase regulator (4) operates, which is regulated by means of a microphone (5). 3. Anordnung nach Anspruch 2, dadurch gekennzeichnet, daß der Sinusgenera tor (3) durch Zündimpulse der Brennkraftmaschine (1) synchronisiert ist.3. Arrangement according to claim 2, characterized in that the Sinusgenera tor (3) is synchronized by ignition pulses from the internal combustion engine (1). 4. Anordnung nach Anspruch 2, dadurch gekennzeichnet, daß der Sinusgenerator (3) mit der Drehzahl einer Kurbelwelle der Brennkraftmaschine (1) oder einem Vielfachen davon synchronisiert ist.4. Arrangement according to claim 2, characterized in that the sine generator (3) with the speed of a crankshaft of the internal combustion engine (1) or a multiple of which is synchronized. 5. Anordnung nach einem der Ansprüche 2 bis 4, dadurch gekennzeichnet, daß der Lautsprecher (8) ein Bestandteil eines Rundfunkempfängers ist.5. Arrangement according to one of claims 2 to 4, characterized in that that the loudspeaker (8) is part of a radio receiver.
DE19813106029 1981-02-19 1981-02-19 Method and arrangement for reducing the noise level in the head region of motor vehicle occupants Withdrawn DE3106029A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19813106029 DE3106029A1 (en) 1981-02-19 1981-02-19 Method and arrangement for reducing the noise level in the head region of motor vehicle occupants

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19813106029 DE3106029A1 (en) 1981-02-19 1981-02-19 Method and arrangement for reducing the noise level in the head region of motor vehicle occupants

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Publication Number Publication Date
DE3106029A1 true DE3106029A1 (en) 1982-09-09

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0098594A2 (en) * 1982-07-07 1984-01-18 Nissan Motor Co., Ltd. A method and apparatus for controlling the sound field in a vehicle cabin or the like
DE3816921A1 (en) * 1988-05-18 1989-11-30 Bayerische Motoren Werke Ag ARRANGEMENT FOR REDUCING NOISE LEVEL IN THE INTERIOR OF A MOTOR VEHICLE
FR2674346A1 (en) * 1991-03-19 1992-09-25 Thomson Csf NOISE SUBTRACTION PROCESS FOR UNDERWATER VEHICLE.
WO1995014988A1 (en) * 1993-11-29 1995-06-01 Caterpillar Inc. Indirectly sensed signal processing in active periodic acoustic noise cancellation
DE19543495A1 (en) * 1995-11-22 1997-05-28 Mann & Hummel Filter Device for insulating noise absorbing elements
US5748748A (en) * 1995-08-26 1998-05-05 Fichtel & Sachs Ag Apparatus and method for influencing oscillations in the passenger compartment of a motor vehicle and apparatus and method for detecting defects in a motor vehicle
US5979962A (en) * 1994-06-10 1999-11-09 Stankiewicz Gmbh Load floor lining having integrated sound insulation
DE4026070C2 (en) * 1989-08-22 2000-05-11 Volkswagen Ag Device for actively reducing a noise level at the location of people
EP2101316A1 (en) * 2008-03-12 2009-09-16 CLAAS Selbstfahrende Erntemaschinen GmbH Agricultural work machine with sound dampened cabin

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2721754A1 (en) * 1976-05-13 1977-11-24 Sound Attenuators Ltd METHOD AND DEVICE FOR REDUCING THE LEVEL OF INTERFERENCE NOISE

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2721754A1 (en) * 1976-05-13 1977-11-24 Sound Attenuators Ltd METHOD AND DEVICE FOR REDUCING THE LEVEL OF INTERFERENCE NOISE

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
US-Z.: The Journal of the Acustical Society of American, Vol. 25, No. 6, Nov. 1953, S. 1130-1136 *

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0098594A2 (en) * 1982-07-07 1984-01-18 Nissan Motor Co., Ltd. A method and apparatus for controlling the sound field in a vehicle cabin or the like
EP0098594A3 (en) * 1982-07-07 1985-06-19 Nissan Motor Co., Ltd. A method and apparatus for controlling the sound field in a vehicle cabin or the like
DE3816921A1 (en) * 1988-05-18 1989-11-30 Bayerische Motoren Werke Ag ARRANGEMENT FOR REDUCING NOISE LEVEL IN THE INTERIOR OF A MOTOR VEHICLE
DE4026070C2 (en) * 1989-08-22 2000-05-11 Volkswagen Ag Device for actively reducing a noise level at the location of people
FR2674346A1 (en) * 1991-03-19 1992-09-25 Thomson Csf NOISE SUBTRACTION PROCESS FOR UNDERWATER VEHICLE.
WO1992016853A1 (en) * 1991-03-19 1992-10-01 Thomson-Csf Noise subtraction method for submarine vehicule
US5502770A (en) * 1993-11-29 1996-03-26 Caterpillar Inc. Indirectly sensed signal processing in active periodic acoustic noise cancellation
WO1995014988A1 (en) * 1993-11-29 1995-06-01 Caterpillar Inc. Indirectly sensed signal processing in active periodic acoustic noise cancellation
US5979962A (en) * 1994-06-10 1999-11-09 Stankiewicz Gmbh Load floor lining having integrated sound insulation
US5748748A (en) * 1995-08-26 1998-05-05 Fichtel & Sachs Ag Apparatus and method for influencing oscillations in the passenger compartment of a motor vehicle and apparatus and method for detecting defects in a motor vehicle
DE19543495A1 (en) * 1995-11-22 1997-05-28 Mann & Hummel Filter Device for insulating noise absorbing elements
EP2101316A1 (en) * 2008-03-12 2009-09-16 CLAAS Selbstfahrende Erntemaschinen GmbH Agricultural work machine with sound dampened cabin
DE102008013846A1 (en) * 2008-03-12 2009-09-17 Claas Selbstfahrende Erntemaschinen Gmbh Agricultural work machine with noise-damped cabin

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8125 Change of the main classification

Ipc: B60R 13/08

8126 Change of the secondary classification

Ipc: G10K 11/16

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8127 New person/name/address of the applicant

Owner name: VOLKSWAGEN AG, 3180 WOLFSBURG, DE

8110 Request for examination paragraph 44
8125 Change of the main classification

Ipc: G10K 11/16

8130 Withdrawal