EP1352172B1 - Silencer with a plurality of resonance chambers - Google Patents

Silencer with a plurality of resonance chambers Download PDF

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Publication number
EP1352172B1
EP1352172B1 EP02701191A EP02701191A EP1352172B1 EP 1352172 B1 EP1352172 B1 EP 1352172B1 EP 02701191 A EP02701191 A EP 02701191A EP 02701191 A EP02701191 A EP 02701191A EP 1352172 B1 EP1352172 B1 EP 1352172B1
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EP
European Patent Office
Prior art keywords
sound absorber
hollow body
helmholtz resonators
absorber according
component
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Revoked
Application number
EP02701191A
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German (de)
French (fr)
Other versions
EP1352172A1 (en
Inventor
Thomas Zirkelbach
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Mahle Filtersysteme GmbH
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Mahle Filtersysteme GmbH
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Application filed by Mahle Filtersysteme GmbH filed Critical Mahle Filtersysteme GmbH
Publication of EP1352172A1 publication Critical patent/EP1352172A1/en
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Classifications

    • 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
    • F01N1/02—Silencing apparatus characterised by method of silencing by using resonance
    • F01N1/026—Annular resonance chambers arranged concentrically to an exhaust passage and communicating with it, e.g. via at least one opening in the exhaust passage
    • 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
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
    • F01N13/0097—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series the purifying devices are arranged in a single housing
    • 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
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/011—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more purifying devices arranged in parallel
    • F01N13/017—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more purifying devices arranged in parallel the purifying devices are arranged in a single housing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M35/00—Combustion-air cleaners, air intakes, intake silencers, or induction systems specially adapted for, or arranged on, internal-combustion engines
    • F02M35/12—Intake silencers ; Sound modulation, transmission or amplification
    • F02M35/1205—Flow throttling or guiding
    • F02M35/1216—Flow throttling or guiding by using a plurality of holes, slits, protrusions, perforations, ribs or the like; Surface structures; Turbulence generators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M35/00—Combustion-air cleaners, air intakes, intake silencers, or induction systems specially adapted for, or arranged on, internal-combustion engines
    • F02M35/12—Intake silencers ; Sound modulation, transmission or amplification
    • F02M35/1255—Intake silencers ; Sound modulation, transmission or amplification using resonance
    • F02M35/1261—Helmholtz resonators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M35/00—Combustion-air cleaners, air intakes, intake silencers, or induction systems specially adapted for, or arranged on, internal-combustion engines
    • F02M35/12—Intake silencers ; Sound modulation, transmission or amplification
    • F02M35/1255—Intake silencers ; Sound modulation, transmission or amplification using resonance
    • F02M35/1266—Intake silencers ; Sound modulation, transmission or amplification using resonance comprising multiple chambers or compartments
    • 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
    • G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M35/00—Combustion-air cleaners, air intakes, intake silencers, or induction systems specially adapted for, or arranged on, internal-combustion engines
    • F02M35/14—Combined air cleaners and silencers

Definitions

  • the invention relates to a silencer on or in a Component in which there is a sound to be damped, in particular Airborne sound, spreads.
  • Silencers are used, for example, in internal combustion engines used to reduce noise emissions to the environment.
  • silencers are in an exhaust tract an internal combustion engine arranged around the engine generated and propagated sound to dampen.
  • Silencers also come in motor vehicles in a fresh air tract of the internal combustion engine for use, to e.g. one charged with an exhaust gas turbocharger Internal combustion engine generated by the turbocharger and dampen sound propagating in the fresh air tract.
  • Helmholtz resonators To attenuate sound that propagates in a line, are so-called “shunt resonators” or “Helmholtz resonators” known.
  • a Helmholtz resonator consists essentially of a cavity that has a Connection opening communicates with the inside of the line, in which the sound to be damped spreads, whereby the The cavity is otherwise closed. The one enclosed in the cavity The gas volume acts as a "spring” and the gas volume in the connection opening acts as a “mass”, causing an oscillatory system is formed.
  • This vibration system can be excited to vibrate by sound waves, whereby energy is extracted from the sound waves, i.e. the Sound is dampened.
  • the damping effect of such Helmholtz resonator is on a certain frequency or limited to a specific frequency band.
  • the frequency or the frequency band in which the Helmholtz resonator is Damping effect depends, e.g. from the geometry, the cross section, the length and thus the volume of the cavity and the connection opening of the Helmholtz resonator from.
  • a Helmholtz resonator can have its damping effect on best unfold when it is positioned on the line is that its connection opening is right there with the Inside the line communicates where in the line one Antinode of a standing sound wave from that Has formed frequency that attenuated by the Helmholtz resonator shall be.
  • a silencer of the type mentioned is disclosed DE-A-1 981 8873.
  • the present invention addresses the problem an embodiment for such a silencer specify which is relatively easy to assemble and / or can be integrated and has a high damping effect guaranteed.
  • a silencer is said be specified, the improved damping effect and in particular has an increased broadband effect.
  • the muffler should be particularly inexpensive to manufacture his.
  • this problem is solved by a silencer solved with the characterizing features of claim 1.
  • the invention is based on the general idea of a Silencer with several, especially with a multitude, To equip Helmholtz resonators arranged together are and parallel to each other their sound absorbing effect unfold.
  • a compact design results when neighboring Adjacent Helmholtz resonators. It is advantageous an embodiment in which the adjacent Helmholtz resonators common walls or common Own wall sections. This will manufacture the Helmholtz resonators simplified.
  • the damping effect, especially the broadband effect, of the silencer according to the invention can improve at least some of the Helmholtz resonators differ from each other distinguish that their cavities and / or their Connection openings of different lengths and / or cross sections and / or have geometries and / or orientations.
  • silencer can e.g. at Exhaust fans, cooling fans, air extraction systems, air conditioning systems, Computers are used to target specific ones Dampen frequencies.
  • the silencer 1 can be a silencer according to the invention 1 in an internal combustion engine 2 to be used there Attenuate sound that is essentially from an exhaust gas turbocharger 3 of the internal combustion engine 2 is generated.
  • the silencer For this purpose, 1 is in a fresh air tract 4 downstream of an air filter 5 and upstream of a compressor 6 of the exhaust gas turbocharger 3 arranged.
  • the silencer 1 in a component, namely in a line 7 of the fresh air tract 4 installed is thus the one in the fresh air tract 4 air flows through and forms a component of the line 7.
  • the turbocharger 3 generated sound propagates through line 7, counter the direction of flow and would - in the absence of a silencer 1 - reach the air filter 5 relatively undamped and finally exit into the environment.
  • the silencer 1 is preferably as close as possible positioned at the sound source whose sound is damped should, so here, close to the exhaust gas turbocharger 3.
  • the arrangement shown in FIG. 1 is preferably found in a motor vehicle again that the internal combustion engine 2 contains as a drive motor.
  • the invention is also applicable to stationary internal combustion engines 2. With this one
  • the embodiment shown is essentially that of the exhaust gas turbocharger 3 generated higher frequency sound at least in certain frequencies are damped. It is also e.g. possible for an internal combustion engine without an exhaust gas turbocharger, that of the internal combustion engine or components thereof, e.g. generated by the valves of the internal combustion engine 2 Dampen sound.
  • the silencer according to the invention 1 a tubular hollow body 8, which is a component the line 7 forms in which the silencer 1 is installed or is involved.
  • the hollow body 8 can how here, be cylindrical. Other embodiments e.g. with a conical hollow body are also possible.
  • Axial section 9 of the hollow body 8 which extends along here of the entire hollow body 8 extends are on an outside of the hollow body 8 a variety of Helmholtz resonators 10 one behind the other in the axial direction and in the circumferential direction arranged side by side.
  • Each of these Helmholtz resonators 10 has a cavity 11, and each of these cavities 11 communicates with via a single connection opening 12 an interior 13 of the hollow body 8 Cavities 11 of the Helmholtz resonators 10 are closed.
  • the inventive Silencer 1 especially at higher frequencies, e.g. from 900 Hz, develop a relatively strong damping effect, which is due to the large number of individual, effective in parallel Helmholtz resonators 10 is returned.
  • zones 14 can be formed, in each case side by side and Helmholtz resonators arranged one behind the other 10 are formed. These zones extend 14 only partially along the circumference of the hollow body 8 and 3 are opposite one another on the hollow body 8 arranged.
  • a single zone 14 may be formed, which extend along the entire circumference of the hollow body 8 and thus extends in the circumferential direction completely encloses. Accordingly, they are Helmholtz resonators 10 along the entire circumference side by side arranged on the hollow body 8.
  • Other embodiments can also have more than two such zones 14.
  • FIG. 3 shows an embodiment in which the Helmholtz resonators 10 or their cavities 11 and their connecting openings 12 radially to a longitudinal axis 15 of the hollow body 8 are aligned.
  • adjacent borders Helmholtz resonators 10 against each other.
  • adjacent Helmholtz resonators 10 common Walls or wall sections 16, whereby their Manufacturing simplified.
  • the cavities 11 can Helmholtz resonators 10 basically any cross sections exhibit. However, circular, rectangular ones are preferred or hexagonal cross sections.
  • At least some of the Helmholtz resonators 10 can differ from each other by their cavities 11 and / or their connecting openings 12 different lengths and / or cross sections and / or geometries and / or orientations have. As a result, the damping behavior, in particular affects the broadband effect of the silencer 1 become.
  • the hollow body 8 has a circular Cross-section. It is clear that the hollow body 8 at least basically in the area of its axial section 9 can have any cross section, in particular a rectangular or polygonal cross section.
  • an embodiment is preferred for a distance at least in the axial direction of the hollow body 8 17 between the connection openings 12 of two adjacent ones Helmholtz resonators 10 is smaller than a whole or one half the wavelength of a frequency to be attenuated or less is as a whole or half a medium wavelength of a frequency band to be attenuated. Because of this design is achieved that it is in the assembly of the invention Muffler 1 is not on an exact positioning of the Muffler 1 arrives at or in line 7. Because like that long the one equipped with the Helmholtz resonators 10 Axial section 9 positioned in the region of an antinode there is at least one of the Helmholtz resonators 10 relatively close or exactly at the maximum of the antinode. In this way, an optimal damping effect can always be achieved be guaranteed for the silencer 1.
  • the invention Silencer 1 should be constructed so that the cavities 11 of at least some of the Helmholtz resonators 10 in one common block are formed, for example has a honeycomb structure or "honeycomb structure".
  • This block then forms a separately producible component, which are attached to a wall section of the hollow body 8 can.
  • This wall section is with the connection openings 12 equipped.
  • Cavity 11 is assigned a separate connection opening 12.
  • the wall section thus delimits the block radially on the inside. Radial the block is outside, for example, by a common one Cover bounded by the cavities 11 radially outside closes.
  • the embodiment 3 provided two zones 14 each be trained this way.
  • the hollow body 8 Be designed as a housing in which the separately manufactured block containing the cavities 11 can be used is. By closing this housing with a suitable one At the same time, the cavities 11 become radially outer lids locked.
  • the block can be connected to the wall section of the Hollow body 8 and / or with the lid in a suitable manner connected, in particular welded.
  • the component in which the sound to be damped spreads is in the described embodiment through the line 7 formed.
  • the component in which the damping is located Sound propagates through another component of the Fresh air track is formed, for example by the Air filter 5 or by a fresh air collector 18, of which the fresh air supplied to the individual cylinders the internal combustion engine 2 distributed (see. Fig. 1).
  • the silencer Housing or a component, e.g. a housing wall, the Component the silencer according to the invention formed on or in the lid of the air filter 5 his.
  • the silencer can be used as an attachment or be designed as a built-in part on or in the respective Component is assembled.
  • Silencer as an integral part of the respective component embody.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Exhaust Silencers (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)

Abstract

The invention relates to a sound absorber (1) mounted on or in a component (7), wherein a sound which is to be absorbed is propagated. The silencer (1) comprises a hollow body (8), which communicates with the component (7) or forms a component part of said component (7). A plurality of Helmholtz resonators (10) which operate in a parallel manner are arranged behind each other in the axial direction of the hollow body (8) in at least one axial part (9) of said hollow body (8).

Description

Die Erfindung betrifft einen Schalldämpfer an oder in einem Bauteil, in dem sich ein zu bedämpfender Schall, insbesondere Luftschall, ausbreitet.The invention relates to a silencer on or in a Component in which there is a sound to be damped, in particular Airborne sound, spreads.

Schalldämpfer werden beispielsweise bei Brennkraftmaschinen zur Reduzierung von Schallemissionen in die Umgebung benutzt. Zum Beispiel werden Schalldämpfer in einem Abgastrakt einer Brennkraftmaschine angeordnet, um den von der Brennkraftmaschine erzeugten und sich darin ausbreitenden Schall zu dämpfen. Ebenso kommen bei Kraftfahrzeugen Schalldämpfer in einem Frischlufttrakt der Brennkraftmaschine zur Anwendung, um z.B. bei einer mit einem Abgasturbulader aufgeladenen Brennkraftmaschine den vom Abgasturbolader erzeugten und sich im Frischlufttrakt ausbreitenden Schall zu dämpfen.Silencers are used, for example, in internal combustion engines used to reduce noise emissions to the environment. For example, silencers are in an exhaust tract an internal combustion engine arranged around the engine generated and propagated sound to dampen. Silencers also come in motor vehicles in a fresh air tract of the internal combustion engine for use, to e.g. one charged with an exhaust gas turbocharger Internal combustion engine generated by the turbocharger and dampen sound propagating in the fresh air tract.

Zur Dämpfung von Schall, der sich in einer Leitung ausbreitet, sind sogenannte "Nebenschlußresonatoren" oder "Helmholtzresonatoren" bekannt. Ein solcher Helmholtzresonator besteht im wesentlichen aus einem Hohlraum, der über eine Verbindungsöffnung mit dem Inneren der Leitung kommuniziert, in der sich der zu bedämpfende Schall ausbreitet, wobei der Hohlraum im übrigen geschlossen ist. Das im Hohlraum eingeschlossene Gasvolumen wirkt dabei als "Feder" und das Gasvolumen in der Verbindungsöffnung wirkt als "Masse", wodurch ein schwingungsfähiges Systems gebildet wird. Dieses Schwingungssystem ist durch Schallwellen zu Schwingungen anregbar, wobei den Schallwellen Energie entzogen wird, das heißt der Schall wird bedämpft. Die Dämpfungswirkung eines solchen Helmholtzresonators ist jedoch auf eine bestimmte Frequenz bzw. auf ein bestimmtes Frequenzband begrenzt. Die Frequenz bzw. das Frequenzband, bei dem der Helmholtzresonator seine Dämpfungswirkung entfaltet, hängt z.B. von der Geometrie, dem Querschnitt, der Länge und somit vom Volumen des Hohlraums sowie der Verbindungsöffnung des Helmholtzresonators ab. Ein Helmholtzresonator kann seine Dämpfungswirkung am besten dann entfalten, wenn er so an der Leitung positioniert wird, daß seine Verbindungsöffnung genau dort mit dem Inneren der Leitung kommuniziert, wo sich in der Leitung ein Schwingungsbauch einer stehenden Schallwelle von derjenigen Frequenz ausgebildet hat, die vom Helmholtzresonator bedämpft werden soll. Durch die Geometrie der Leitung, in der sich der Schall ausbreitet, sind diejenigen Positionen vorgegeben, in denen sich eine stehende Schallwelle ausbilden kann. Die genaue Position eines Schwingungsbauchs kann bei vorgegebener Frequenz berechnet werden. Um eine optimale Bedämpfung einer bestimmten Frequenz zu erzielen, muß dann der Helmholtzresonator möglichst genau an der berechneten Stelle an die Leitung angeschlossen werden. Im Rahmen einer Großserienfertigung, wie sie beispielsweise bei der Produktion von Kraftfahrzeugen bzw. von Fahrzeugkomponenten die Regel' ist, kann die genaue Einhaltung einer gewünschten Montageposition nur mit einem relativ hohen Aufwand sichergestellt werden. Darüber hinaus ist die Bandbreite der mit einem herkömmlichen, mit einem Helmholtzresonator ausgestatteten Schalldämpfer, bedämpfbaren Frequenzen sehr eng, so daß regelmäßig nur Pegelspitzen bestimmter Frequenzen bedämpfbar sind.To attenuate sound that propagates in a line, are so-called "shunt resonators" or "Helmholtz resonators" known. Such a Helmholtz resonator consists essentially of a cavity that has a Connection opening communicates with the inside of the line, in which the sound to be damped spreads, whereby the The cavity is otherwise closed. The one enclosed in the cavity The gas volume acts as a "spring" and the gas volume in the connection opening acts as a "mass", causing an oscillatory system is formed. This vibration system can be excited to vibrate by sound waves, whereby energy is extracted from the sound waves, i.e. the Sound is dampened. The damping effect of such Helmholtz resonator, however, is on a certain frequency or limited to a specific frequency band. The frequency or the frequency band in which the Helmholtz resonator is Damping effect depends, e.g. from the geometry, the cross section, the length and thus the volume of the cavity and the connection opening of the Helmholtz resonator from. A Helmholtz resonator can have its damping effect on best unfold when it is positioned on the line is that its connection opening is right there with the Inside the line communicates where in the line one Antinode of a standing sound wave from that Has formed frequency that attenuated by the Helmholtz resonator shall be. Due to the geometry of the line in which the sound propagates, those positions are given in which a standing sound wave is formed can. The exact position of an antinode can be at predetermined frequency can be calculated. For optimal damping to achieve a certain frequency, the Helmholtz resonator as precisely as possible at the calculated point be connected to the line. As part of a large series production, such as in the production of Motor vehicles or vehicle components is the rule, can strictly adhere to a desired mounting position can only be ensured with a relatively high effort. In addition, the bandwidth of a conventional, silencers equipped with a Helmholtz resonator, dampable frequencies very closely, so regularly only level peaks of certain frequencies can be damped.

Einen Schalldämpfer der eingangs genannten Art offenbart die DE-A-1 981 8873.A silencer of the type mentioned is disclosed DE-A-1 981 8873.

Die vorliegende Erfindung beschäftigt sich mit dem Problem, für einen solchen Schalldämpfer eine Ausführungsform anzugeben, die relativ einfach montierbar und/oder integrierbar ist und dabei eine hohe Dämpfungswirkung gewährleistet. Darüber hinaus soll ein Schalldämpfer angegeben werden, der eine verbesserte Dämpfungswirkung und insbesondere eine vergrößerte Breitbandwirkung aufweist. Außerdem soll der Schalldämpfer besonders preiswert herstellbar sein.The present invention addresses the problem an embodiment for such a silencer specify which is relatively easy to assemble and / or can be integrated and has a high damping effect guaranteed. In addition, a silencer is said be specified, the improved damping effect and in particular has an increased broadband effect. Moreover the muffler should be particularly inexpensive to manufacture his.

Dieses Problem wird erfindungsgemäß durch einen Schalldämpfer mit den kennzeichnenden Merkmalen des Anspruchs 1 gelöst.According to the invention, this problem is solved by a silencer solved with the characterizing features of claim 1.

Die Erfindung beruht auf dem allgemeinen Gedanken, einen Schalldämpfer mit mehreren, insbesondere mit einer Vielzahl, Helmholtzresonatoren auszustatten, die beieinander angeordnet sind und parallel zueinander ihre schalldämpfende Wirkung entfalten. Durch die Anordnung der Helmholtzresonatoren in Schallausbreitungsrichtung hintereinander kommt es auf die genaue Positionierung des Schalldämpfers am oder im Bauteil, z.B. einer Leitung, in der sich der zu bedämpfende Schall ausbreitet, nicht an, da von den mehreren Helmholtzresonatoren wenigstens einer zwangsläufig nahe oder direkt an einem Schwingungsbauch positioniert ist. Da somit keine besonders genaue Montagetoleranzen eingehalten werden müssen, erleichtert sich die Serienherstellung bzw. die serienmäßige Ausstattung eines Bauteils mit dem erfindungsgemäßen Schalldämpfer.The invention is based on the general idea of a Silencer with several, especially with a multitude, To equip Helmholtz resonators arranged together are and parallel to each other their sound absorbing effect unfold. The arrangement of the Helmholtz resonators in the direction of sound propagation one after the other the exact positioning of the silencer on or in the component, e.g. a line in which the person to be dampened Sound propagates, not because of the several Helmholtz resonators at least one inevitably close or direct is positioned on an antinode. So there is none particularly precise assembly tolerances must be observed, Series production or serial production is easier Equipment of a component with the invention Silencer.

Desweiteren hat sich gezeigt, daß der mit mehreren, parallel wirkender Helmholtzresonatoren ausgestattete Schalldämpfer eine relativ breitbandige Dämpfungswirkung entfaltet, so daß der erfindungsgemäße Schalldämpfer insgesamt über eine verbesserte Dämpfungswirkung verfügt. Diese Breitbandwirkung ergibt sich insbesondere aus einer gewollten oder tolerierten Ungleichförmigkeit der einzelnen Helmholtzresonatoren, die sich bei deren Herstellung ergibt.Furthermore, it has been shown that the one with several, parallel Acting silencers equipped with Helmholtz resonators develops a relatively broadband damping effect, so that the muffler according to the invention improved overall Damping effect. This broadband effect results in particular from a wanted or tolerated Non-uniformity of the individual Helmholtz resonators, that results from their manufacture.

Von besonderem Vorteil ist die erfindungsgemäße Ausführungsform, bei der in einem Axialabschnitt eines Hohlkörpers des Schalldämpfers in einer, sich in Achsrichtung und in Umfangsrichtung des Hohlkörpers erstreckenden Zone mehrere, parallel wirkende Helmholtzresonatoren in Achsrichtung hintereinander und in Umfangsrichtung nebeneinander angeordnet sind. Hierdurch ergibt sich eine flächige Anordnung einer Vielzahl von Helmholtzresonatoren am Hohlkörper, wodurch die Dämpfungswirkung bzw. die Breitbandigkeit zusätzlich erhöht ist.The embodiment according to the invention, in which in an axial section of a hollow body of the muffler in one, in the axial direction and in the circumferential direction of the hollow body extending zone several, parallel acting Helmholtz resonators in the axial direction one behind the other and in the circumferential direction are arranged side by side. This gives a flat arrangement of a large number of Helmholtz resonators on the hollow body, which reduces the damping effect or broadband is additionally increased.

Eine kompakte Bauform ergibt sich dann, wenn benachbarte Helmholtzresonatoren aneinander angrenzen. Vorteilhaft ist dabei eine Ausführungsform, bei der die aneinander angrenzenden Helmholtzresonatoren gemeinsame Wände bzw. gemeinsamen Wandabschnitte besitzen. Hierdurch wird die Herstellung der Helmholtzresonatoren vereinfacht.A compact design results when neighboring Adjacent Helmholtz resonators. It is advantageous an embodiment in which the adjacent Helmholtz resonators common walls or common Own wall sections. This will manufacture the Helmholtz resonators simplified.

Von besonderem Vorteil ist eine Ausführungsform, bei der die Querschnitte der Helmholtzresonatoren klein sind im Vergleich zum Querschnitt des Hohlkörpers. Hierdurch wird eine Ausführungsform gebildet, die sich durch ihre Kompaktheit auszeichnet und somit auch bei einem relativ geringen Einbauraum verwendbar ist. Dabei hat sich gezeigt, daß die Helmholtzresonatoren aufgrund ihrer großen Anzahl trotz ihrer geringen Abmessungen eine relativ große Dämpfungswirkung entfalten, so daß der erfindungsgemäße Schalldämpfer im Vergleich zu einem herkömmlichen Schalldämpfer kleiner baut, dabei eine ausreichende Dämpfungswirkung bei größerer Bandbreite entfaltet. Insbesondere für hohe oder höhere Frequenzen, z.B. ab etwa 900 Hz können mit einem klein bauenden Schalldämpfer große Dämpfungswerte erzielt werden.An embodiment in which the Cross sections of the Helmholtz resonators are small in comparison to the cross section of the hollow body. This will create a Embodiment formed by their compactness distinguished and thus also with a relatively small installation space is usable. It has been shown that the Helmholtz resonators due to their large number despite their small dimensions a relatively large damping effect unfold so that the silencer according to the invention in comparison builds smaller to a conventional silencer, a sufficient damping effect with a wider bandwidth unfolded. Especially for high or higher frequencies, e.g. from around 900 Hz can be built with a small Large damping values can be achieved.

Um die Dämpfungswirkung, insbesondere die Breitbandwirkung, des erfindungsgemäßen Schalldämpfers zu verbessern, können sich zumindest einige der Helmholtzresonatoren dadurch voneinander unterscheiden, daß ihre Hohlräume und/oder ihre Verbindungsöffnungen unterschiedliche Längen und/oder Querschnitte und/oder Geometrien und/oder Orientierungen aufweisen.The damping effect, especially the broadband effect, of the silencer according to the invention can improve at least some of the Helmholtz resonators differ from each other distinguish that their cavities and / or their Connection openings of different lengths and / or cross sections and / or have geometries and / or orientations.

Besondere Anwendungen und Verwendungen des erfindungsgemäßen Schalldämpfers ergeben sich aus den Ansprüchen 19 bis 21. Special applications and uses of the invention Silencer result from claims 19 to 21.

Weitere Vorteile der Erfindung ergeben sich aus den Unteransprüchen, aus den Zeichnungen und aus der zugehörigen Figurenbeschreibung anhand der Zeichnungen.Further advantages of the invention result itself from the dependent claims, from the drawings and from the associated description of the figures using the drawings.

Es versteht sich, daß die vorstehend genannten und die nachstehend noch zu erläuternden Merkmale nicht nur in der jeweils angegebenen Kombination, sondern auch in anderen Kombinationen oder in Alleinstellung verwendbar sind, ohne den Rahmen der vorliegenden Erfindung zu verlassen.It is understood that the above and those below Features to be explained not only in each case specified combination, but also in other combinations or can be used alone without the To leave the scope of the present invention.

Bevorzugte Ausführungsbeispiele der Erfindung sind in den Zeichnungen dargestellt und werden in der nachfolgenden Beschreibung näher erläutert. Obwohl die nachfolgenden Ausführungsbeispiele eine besondere Verwendung des erfindungsgemäßen Schalldämpfer bei einer Brennkraftmaschine erläutern, ist klar, daß dies ohne Beschränkung der Allgemeinheit der vorliegenden Erfindung erfolgt. Insbesondere kann der erfindungsgemäße Schalldämpfer stets dann zur Anwendung kommen, wenn in einem Gerät Luftschall erzeugt oder übertragen wird. Dabei eignet sich der erfindungsgemäße Schalldämpfer aufgrund seines kompakten Aufbaus in besondere Weise für eine Verwendung in oder an kleineren Geräten zur Dämpfung hoher oder höherer Frequenzen, beispielsweise ab 900 Hz. Beispielsweise kann der erfindungsgemäße Schalldämpfer bei Haushaltsgeräten zur Anwendung kommen, z.B. Waschmaschine, Spülmaschine, Wäschetrockner, Haartrockner, Staubsauger, Dunstabzugshaube. Ebenso ist eine Anwendung bei elektromotorisch betriebenen oder druckluftbetriebenen Werkzeugen möglich, die insbesondere mit hohen Drehzahlen arbeiten. Desweiteren kann der Schalldämpfer nach der Erfindung z.B. bei Abluftgebläsen, Kühlgebläsen, Luftabsauganlagen, Klimaanlagen, Computern zum Einsatz kommen, um dort gezielt bestimmte Frequenzen zu bedämpfen.Preferred embodiments of the invention are in the Drawings are shown in the description below explained in more detail. Although the following embodiments a special use of the invention Explain silencers in an internal combustion engine, it is clear that this is without restricting the generality of the present invention. In particular, the invention Silencers are always used, when airborne sound is generated or transmitted in a device. The silencer according to the invention is suitable here its compact design in a special way for one Use in or on smaller devices for high damping or higher frequencies, for example from 900 Hz. For example can the silencer according to the invention Household appliances, e.g. Washing machine, Dishwasher, tumble dryer, hair dryer, vacuum cleaner, Hood. There is also an application for electric motors operated or compressed air operated tools possible, that work especially at high speeds. Furthermore the silencer according to the invention can e.g. at Exhaust fans, cooling fans, air extraction systems, air conditioning systems, Computers are used to target specific ones Dampen frequencies.

Es zeigen, jeweils schematisch,

Fig. 1
eine schaltplanartige Prinzipdarstellung einer Brennkraftmaschine, die mit einem erfindungsgemäßen Schalldämpfer ausgestattet ist,
Fig. 2
einen Längsschnitt durch einen erfindungsgemäßen Schalldämpfer,
Fig. 3
einen Querschnitt durch einen erfindungsgemäßen Schalldämpfer und
Fig. 4
ein Querschnitt wie in Fig. 3, jedoch bei einer anderen Ausführungsform.
Each shows schematically
Fig. 1
2 shows a schematic diagram of an internal combustion engine which is equipped with a silencer according to the invention,
Fig. 2
a longitudinal section through a silencer according to the invention,
Fig. 3
a cross section through a silencer according to the invention and
Fig. 4
a cross section as in Fig. 3, but in another embodiment.

Entsprechend Fig. 1 kann ein erfindungsgemäßer Schalldämpfer 1 bei einer Brennkraftmaschine 2 zum Einsatz kommen, um dort Schall zu dämpfen, der im wesentlichen von einem Abgasturbolader 3 der Brennkraftmaschine 2 erzeugt wird. Der Schalldämpfer 1 ist zu diesem Zweck in einem Frischlufttrakt 4 stromab eines Luftfilters 5 und stromauf eines Verdichters 6 des Abgasturboladers 3 angeordnet. Dabei ist der Schalldämpfer 1 in ein Bauteil, nämlich in eine Leitung 7 des Frischlufttraktes 4 eingebaut, wird somit von der im Frischlufttrakt 4 transportierten Luft durchströmt und bildet insoweit einen Bestandteil der Leitung 7. Der vom Abgasturbolader 3 erzeugte Schall breitet sich durch die Leitung 7, entgegen der Strömungsrichtung aus und würde - bei fehlendem Schalldämpfer 1 - relativ unbedämpft bis zum Luftfilter 5 gelangen und schließlich in die Umgebung austreten. Durch die Einbindung des Schalldämpfers 1 in die Leitung 7 kann der sich in der Leitung 7 ausbreitende Schall hinsichtlich bestimmter Frequenzen bzw. Frequenzbändern bedämpft werden, wodurch sich die Schallemission der gesamten Anordnung reduzieren läßt. Vorzugsweise wird der Schalldämpfer 1 möglichst nahe an der Schallquelle positioniert, deren Schall bedämpft werden soll, also hier, nahe am Abgasturbolader 3. Im Ausführungsbeispiel ist der Schalldämpfer 1 reinluftseitig, also stromab des Luftfilters 5 angeordnet; ebenso ist eine rohluftseitige Anordnung möglich.1 can be a silencer according to the invention 1 in an internal combustion engine 2 to be used there Attenuate sound that is essentially from an exhaust gas turbocharger 3 of the internal combustion engine 2 is generated. The silencer For this purpose, 1 is in a fresh air tract 4 downstream of an air filter 5 and upstream of a compressor 6 of the exhaust gas turbocharger 3 arranged. Here is the silencer 1 in a component, namely in a line 7 of the fresh air tract 4 installed, is thus the one in the fresh air tract 4 air flows through and forms a component of the line 7. The turbocharger 3 generated sound propagates through line 7, counter the direction of flow and would - in the absence of a silencer 1 - reach the air filter 5 relatively undamped and finally exit into the environment. Through the integration of the silencer 1 in the line 7 can be in the line 7 propagating sound with respect to certain Frequencies or frequency bands are damped, whereby the noise emission of the entire arrangement is reduced leaves. The silencer 1 is preferably as close as possible positioned at the sound source whose sound is damped should, so here, close to the exhaust gas turbocharger 3. In the embodiment is the silencer 1 on the clean air side, so arranged downstream of the air filter 5; is also one arrangement on the raw air side possible.

Vorzugsweise findet sich die in Fig. 1 dargestellte Anordnung in einem Kraftfahrzeug wieder, das die Brennkraftmaschine 2 als Antriebsmotor enthält. Ebenso ist die Erfindung auf stationäre Brennkraftmaschinen 2 anwendbar. Bei der hier gezeigten Ausführungsform soll im wesentlich der vom Abgasturbolader 3 erzeugte höherfrequente Schall zumindest in bestimmten Frequenzen bedämpft werden. Ebenso ist es z.B. bei einer Brennkraftmaschine ohne Abgasturbolader möglich, den von der Brennkraftmaschine oder Bestandteilen davon, z.B. von den Ventilen der Brennkraftmaschine 2, erzeugten Schall zu bedämpfen. The arrangement shown in FIG. 1 is preferably found in a motor vehicle again that the internal combustion engine 2 contains as a drive motor. The invention is also applicable to stationary internal combustion engines 2. With this one The embodiment shown is essentially that of the exhaust gas turbocharger 3 generated higher frequency sound at least in certain frequencies are damped. It is also e.g. possible for an internal combustion engine without an exhaust gas turbocharger, that of the internal combustion engine or components thereof, e.g. generated by the valves of the internal combustion engine 2 Dampen sound.

Entsprechend Fig. 2 weist der erfindungsgemäße Schalldämpfer 1 einen rohrförmigen Hohlkörper 8 auf, der einen Bestandteil der Leitung 7 bildet, in welche der Schalldämpfer 1 eingebaut bzw. eingebunden ist. Der Hohlkörper 8 kann dabei, wie hier, zylindrisch ausgebildet sein. Andere Ausführungsformen, z.B. mit kegelförmigem Hohlkörper, sind ebenfalls möglich.2, the silencer according to the invention 1 a tubular hollow body 8, which is a component the line 7 forms in which the silencer 1 is installed or is involved. The hollow body 8 can how here, be cylindrical. Other embodiments e.g. with a conical hollow body are also possible.

In einem durch eine geschweifte Klammer gekennzeichneten Axialabschnitt 9 des Hohlkörpers 8, der sich hier entlang des gesamten Hohlkörpers 8 erstreckt, sind an einer Außenseite des Hohlkörpers 8 eine Vielzahl von Helmholtzresonatoren 10 in Achsrichtung hintereinander und in Umfangsrichtung nebeneinander angeordnet. Jeder dieser Helmholtzresonatoren 10 weist einen Hohlraum 11 auf, und jeder dieser Hohlräume 11 kommuniziert über eine einzige Verbindungsöffnung 12 mit einem Inneren 13 des Hohlkörpers 8. Im übrigen sind die Hohlräume 11 der Helmholtzresonatoren 10 verschlossen. Durch die gewählte Anordnung der Helmholtzresonatoren 10 wirken diese gleichzeitig und somit parallel mit dem Inneren 13 des Hohlkörpers 8 bzw. der Leitung 7 zusammen. Bemerkenswert ist dabei, daß die einzelnen Helmholtzresonatoren 10 im Vergleich zur Leitung 7 relativ klein dimensioniert sind, da die Querschnitte der Helmholtzresonatoren 10 bzw. der Hohlräume 11 klein sind im Vergleich zum Querschnitt der Leitung 7 bzw. des Hohlkörpers 8. Dennoch kann der erfindungsgemäße Schalldämpfer 1, insbesondere bei höheren Frequenzen, z.B. ab 900 Hz, eine relativ starke Dämpfungswirkung entfalten, was auf die große Anzahl der einzelnen, parallel wirksamen Helmholtzresonatoren 10 zurückgeführt wird.In one marked with a curly bracket Axial section 9 of the hollow body 8, which extends along here of the entire hollow body 8 extends are on an outside of the hollow body 8 a variety of Helmholtz resonators 10 one behind the other in the axial direction and in the circumferential direction arranged side by side. Each of these Helmholtz resonators 10 has a cavity 11, and each of these cavities 11 communicates with via a single connection opening 12 an interior 13 of the hollow body 8 Cavities 11 of the Helmholtz resonators 10 are closed. By the selected arrangement of the Helmholtz resonators 10 act these simultaneously and therefore parallel to the interior 13 of the Hollow body 8 or line 7 together. Remarkably while comparing the individual Helmholtz resonators 10 are dimensioned relatively small for line 7 because the cross sections of the Helmholtz resonators 10 or the cavities 11 are small compared to the cross section of the line 7 or the hollow body 8. Nevertheless, the inventive Silencer 1, especially at higher frequencies, e.g. from 900 Hz, develop a relatively strong damping effect, which is due to the large number of individual, effective in parallel Helmholtz resonators 10 is returned.

Entsprechend Fig. 3 können im Axialabschnitt 9 des Hohlkörpers 8 zwei Zonen 14 ausgebildet sein, in denen jeweils nebeneinander und hintereinander angeordnete Helmholtzresonatoren 10 ausgebildet sind. Dabei erstrecken sich diese Zonen 14 nur teilweise entlang des Umfangs des Hohlkörpers 8 und sind gemäß Fig. 3 einander gegenüberliegend am Hohlkörper 8 angeordnet. Im Unterschied dazu kann entsprechend den Ausführungsformen gemäß der Fig. 2 und 4 auch eine einzige Zone 14 ausgebildet sein, die sich entlang des gesamten Umfangs des Hohlkörpers 8 erstreckt und diesen somit in Umfangsrichtung vollständig umschließt. Dementsprechend sind auch die Helmholtzresonatoren 10 entlang des gesamten Umfangs nebeneinander am Hohlkörper 8 angeordnet. Andere Ausführungsformen können auch mehr als zwei solcher Zonen 14 aufweisen.3 can in the axial section 9 of the hollow body 8 two zones 14 can be formed, in each case side by side and Helmholtz resonators arranged one behind the other 10 are formed. These zones extend 14 only partially along the circumference of the hollow body 8 and 3 are opposite one another on the hollow body 8 arranged. In contrast, according to the embodiments 2 and 4 also a single zone 14 may be formed, which extend along the entire circumference of the hollow body 8 and thus extends in the circumferential direction completely encloses. Accordingly, they are Helmholtz resonators 10 along the entire circumference side by side arranged on the hollow body 8. Other embodiments can also have more than two such zones 14.

Während bei der Ausführungsform gemäß Fig. 3 die Helmholtzresonatoren 10 bzw. deren Hohlräume 11 und deren Verbindungsöffnungen 12 parallel zueinander ausgerichtet sind, zeigt Fig. 4 eine Ausführungsform, bei der die Helmholtzresonatoren 10 bzw. deren Hohlräume 11 und deren Verbindungsöffnungen 12 radial zu einer Längsachse 15 des Hohlkörpers 8 ausgerichtet sind.While in the embodiment according to FIG. 3, the Helmholtz resonators 10 or their cavities 11 and their connecting openings 12 are aligned parallel to one another, 4 shows an embodiment in which the Helmholtz resonators 10 or their cavities 11 and their connecting openings 12 radially to a longitudinal axis 15 of the hollow body 8 are aligned.

Bei den gezeigten Ausführungsformen grenzen benachbarte Helmholtzresonatoren 10 aneinander an. Darüber hinaus besitzen die aneinander angrenzenden Helmholtzresonatoren 10 gemeinsame Wände bzw. Wandabschnitte 16, wodurch sich deren Herstellung vereinfacht. Dabei können die Hohlräume 11 der Helmholtzresonatoren 10 grundsätzlich beliebige Querschnitte aufweisen. Bevorzugt werden jedoch kreisförmige, rechteckige oder sechseckige Querschnitte.In the embodiments shown, adjacent borders Helmholtz resonators 10 against each other. In addition own the adjacent Helmholtz resonators 10 common Walls or wall sections 16, whereby their Manufacturing simplified. The cavities 11 can Helmholtz resonators 10 basically any cross sections exhibit. However, circular, rectangular ones are preferred or hexagonal cross sections.

Zumindest einige der Helmholtzresonatoren 10 können sich voneinander unterscheiden, indem ihre Hohlräume 11 und/oder ihre Verbindungsöffnungen 12 unterschiedliche Längen und/oder Querschnitte und/oder Geometrien und/oder Orientierungen besitzen. Hierdurch kann das Dämpfungsverhalten, insbesondere die Breitbandwirkung, des Schalldämpfers 1 beeinflusst werden.At least some of the Helmholtz resonators 10 can differ from each other by their cavities 11 and / or their connecting openings 12 different lengths and / or cross sections and / or geometries and / or orientations have. As a result, the damping behavior, in particular affects the broadband effect of the silencer 1 become.

Gemäß den Fig. 3 und 4 besitzt der Hohlkörper 8 einen kreisförmigen Querschnitt. Es ist klar, dass der Hohlkörper 8 zumindest im Bereich seines Axialabschnitts 9 grundsätzlich einen beliebigen Querschnitt aufweisen kann, insbesondere einen rechteckigen oder polygonalen Querschnitt.3 and 4, the hollow body 8 has a circular Cross-section. It is clear that the hollow body 8 at least basically in the area of its axial section 9 can have any cross section, in particular a rectangular or polygonal cross section.

Entsprechend Fig. 2 wird eine Ausführungsform bevorzugt, bei der zumindest in Achsrichtung des Hohlkörpers 8 ein Abstand 17 zwischen den Verbindungsöffnungen 12 zweier benachbarter Helmholtzresonatoren 10 kleiner ist als eine ganze oder eine halbe Wellenlänge einer zu bedämpfenden Frequenz oder kleiner ist als eine ganze oder eine halbe mittlere Wellenlänge eines zu bedämpfenden Frequenzbandes. Durch diese Bauweise wird erreicht, dass es bei der Montage des erfindungsgemäßen Schalldämpfers 1 nicht auf eine genaue Positionierung des Schalldämpfers 1 an bzw. in der Leitung 7 ankommt. Denn so lange der mit den Helmholtzresonatoren 10 ausgestattete Axialabschnitt 9 im Bereich eines Schwingungsbauches positioniert ist, befindet sich zumindest einer der Helmholtzresonatoren 10 relativ dicht oder genau am Maximum des Schwingungsbauches. Auf diese Weise kann stets eine optimale Dämpfungswirkung für den Schalldämpfer 1 gewährleistet werden.According to FIG. 2, an embodiment is preferred for a distance at least in the axial direction of the hollow body 8 17 between the connection openings 12 of two adjacent ones Helmholtz resonators 10 is smaller than a whole or one half the wavelength of a frequency to be attenuated or less is as a whole or half a medium wavelength of a frequency band to be attenuated. Because of this design is achieved that it is in the assembly of the invention Muffler 1 is not on an exact positioning of the Muffler 1 arrives at or in line 7. Because like that long the one equipped with the Helmholtz resonators 10 Axial section 9 positioned in the region of an antinode there is at least one of the Helmholtz resonators 10 relatively close or exactly at the maximum of the antinode. In this way, an optimal damping effect can always be achieved be guaranteed for the silencer 1.

Bei einer bevorzugten Ausführungsform kann der erfindungsgemäße Schalldämpfer 1 so aufgebaut sein, dass die Hohlräume 11 von zumindest einigen der Helmholtzresonatoren 10 in einem gemeinsamen Block ausgebildet sind, der beispielsweise eine Bienenwaben-Struktur oder "Honeycomb-Struktur" besitzt. Dieser Block bildet dann ein separat herstellbares Bauteil, das an einen Wandabschnitt des Hohlkörpers 8 angebaut werden kann. Dieser Wandabschnitt ist mit den Verbindungsöffnungen 12 ausgestattet. Durch eine geeignete Plazierung des genannten Blocks am dafür vorgesehenen Wandabschnitt wird jedem Hohlraum 11 eine separate Verbindungsöffnung 12 zugeordnet. Der Wandabschnitt begrenzt somit den Block radial innen. Radial außen ist der Block beispielsweise durch einen gemeinsamen Deckel begrenzt, der die Hohlräume 11 radial außen verschließt. Beispielsweise können die bei der Ausführungsform gemäß Fig. 3 vorgesehenen zwei Zonen 14 jeweils auf diese Weise ausgebildet sein. Dabei kann am Hohlkörper 8 eine Art Gehäuse ausgebildet sein, in welches der separat hergestellte, die Hohlräume 11 enthaltende Block einsetzbar ist. Durch das Verschließen dieses Gehäuses mit einem geeigneten Deckel werden gleichzeitig die Hohlräume 11 radial außen verschlossen. Der Block kann mit dem Wandabschnitt des Hohlkörpers 8 und/oder mit dem Deckel auf geeignete Weise verbunden, insbesondere verschweißt sein.In a preferred embodiment, the invention Silencer 1 should be constructed so that the cavities 11 of at least some of the Helmholtz resonators 10 in one common block are formed, for example has a honeycomb structure or "honeycomb structure". This block then forms a separately producible component, which are attached to a wall section of the hollow body 8 can. This wall section is with the connection openings 12 equipped. By a suitable placement of the above Blocks on the designated wall section will be everyone Cavity 11 is assigned a separate connection opening 12. The wall section thus delimits the block radially on the inside. Radial the block is outside, for example, by a common one Cover bounded by the cavities 11 radially outside closes. For example, in the embodiment 3 provided two zones 14 each be trained this way. It can be on the hollow body 8 Be designed as a housing in which the separately manufactured block containing the cavities 11 can be used is. By closing this housing with a suitable one At the same time, the cavities 11 become radially outer lids locked. The block can be connected to the wall section of the Hollow body 8 and / or with the lid in a suitable manner connected, in particular welded.

Das Bauteil, in dem sich der zu bedämpfende Schall ausbreitet, ist im beschriebenen Ausführungsbeispiel durch die Leitung 7 gebildet. Ebenso sind andere Ausführungsformen möglich, bei denen das Bauteil, in dem sich der zu bedämpfende Schall ausbreitet, durch einen anderen Bestandteil des Frischlufttrackts gebildet ist, beispielsweise durch das Luftfilter 5 oder durch einen Frischluftsammler 18, von dem aus sich die zugeführte Frischluft auf die einzelnen Zylinder der Brennkraftmaschine 2 verteilt (vgl. Fig. 1). Vorzugsweise bildet dann der Hohlkörper des Schalldämpfers ein Gehäuse oder einen Bestandteil, z.B. eine Gehäusewand, des Bauteils. Beispielsweise kann der erfindungsgemäße Schalldämpfer am oder im Deckel des Luftfilters 5 ausgebildet sein. Grundsätzlich kann der Schalldämpfer als Anbauteil oder als Einbauteil ausgebildet sein, das am oder im jeweiligen Bauteil montiert wird. Ebenso ist es möglich, den Schalldämpfer als integralen Bestandteil des jeweiligen Bauteils auszugestalten. Beispielsweise ist der Schalldämpfer in das Gehäuse des Luftfilters 5 oder Luftsammlers 8 integriert.The component in which the sound to be damped spreads is in the described embodiment through the line 7 formed. Other embodiments are also possible, where the component in which the damping is located Sound propagates through another component of the Fresh air track is formed, for example by the Air filter 5 or by a fresh air collector 18, of which the fresh air supplied to the individual cylinders the internal combustion engine 2 distributed (see. Fig. 1). Preferably then forms the hollow body of the silencer Housing or a component, e.g. a housing wall, the Component. For example, the silencer according to the invention formed on or in the lid of the air filter 5 his. Basically, the silencer can be used as an attachment or be designed as a built-in part on or in the respective Component is assembled. It is also possible to Silencer as an integral part of the respective component embody. For example, the silencer integrated into the housing of the air filter 5 or air collector 8.

Claims (21)

  1. A sound absorber on or.in a component (7), in which a sound to be absorbed is dispersed, with a hollow body (8), which communicates with the component (7) or forms an element of the component (7),
    whereby at least in one axial section (9) of the hollow body (8) in a zone extending in an axial direction and in a circumferential direction of the hollow body (8), multiple, parallel acting Helmholtz resonators (10) are arranged behind one another in the axial direction of the hollow body (8) and adjacent to one another in the circumferential direction of the hollow body (8),
    whereby each Helmholtz resonator (10) has a hollow chamber (11), which communicates with an interior (13) of the hollow body (8) via a separate connecting opening (12).
  2. The sound absorber according to claim 1,
    characterized in that
    the zone (14) encloses the hollow body (8) completely in the circumferential direction.
  3. The sound absorber according to claim 1,
    characterized in that
    two or more zones (14) are distributed on the hollow body (8).
  4. The sound absorber according to one of claims 1 through 3,
    characterized in that
    adjacent Helmholtz resonators (10) border one another.
  5. The sound absorber according to claim 4,
    characterized in that
    Helmholtz resonators (10) bordering one another have common walls or wall sections (10).
  6. The sound absorber according to one of claims 1 through 5,
    characterized in that
    the cross sections of the Helmholtz resonators (10) are smaller than the cross section of the hollow body (8).
  7. The sound absorber according to one of claims 1 through 6,
    characterized in that
    a distance (17) between Helmholtz resonators (10) adjacent to the connection openings (12) is smaller than a wavelength or half a wavelength of a frequency to be damped or smaller than a middle wave length or half a middle wavelength of a frequency band to be damped.
  8. The sound absorber according to one of claims 1 through 7,
    characterized in that each Helmholtz resonator (10) has a hollow chamber (11), whereby the hollow chambers (11) of multiple Helmholtz resonators (10) are closed radially outward with a common cover.
  9. The sound absorber accordion one of claims 1 through 8,
    characterized in that
    at least some of the Helmholtz resonators (10) differ from one another in by having different lengths and/or cross sections and/or geometries and/or orientations of their hollow chambers (11) and/or their connection openings.
  10. The sound absorber according to one of claims 1 through 9,
    characterized in that
    at least some of the Helmholtz resonators (10) are arranged parallel to one another.
  11. The sound absorber according to one of claims 1 through 10,
    characterized in that
    at least some of the Helmholtz resonators (10) are arranged radially to a longitudinal axis (15) of the hollow body (8).
  12. The sound absorber according to one of claims 1 through 11,
    characterized in that
    at least some of the Helmholtz resonators are formed on the hollow body (8), such that a common block containing the hollow chambers (11) of these Helmholtz resonators (10) is bordered radially outward by a common cover and radially inward by a common wall section of the hollow body (8) containing the connection openings (12) of these Helmholtz resonators (10).
  13. The sound absorber according to claim 12,
    characterized in that
    the block has a honeycomb structure.
  14. The sound absorber according to one of claims 1 through 13,
    characterized in that
    the hollow body (8) forms a housing or a housing element of the component (7).
  15. The sound absorber according to one of claims 1 through 14,
    characterized in that
    the sound absorber (1) is formed as an attaching part for attachment to the component (7) or as a mounting part for installation in the component (7) or as an integrated element of the component (7).
  16. The sound absorber according to one of claims 1 through 15,
    characterized in that
    the component (7) forms an element of a fresh air tract (4) or an exhaust tract of an internal combustion engine (2).
  17. The sound absorber according to claim 16,
    characterized in that
    the sound absorber (1) is arranged in the fresh air tract (4) downstream of an air filter (5) and upstream of an exhaust turbocharger (3) of the internal combustion engine.
  18. The sound absorber according to claim 16 or 17,
    characterized in that
    the component is formed by a line (7) or an air filter or an air accumulator.
  19. A use of a sound absorber (1) according to one of claims 1 through 18 on or in an apparatus, which is operated by a combustion engine or with an electric engine or with compressed air.
  20. The use according to claim 19,
    characterized in that
    the apparatus is formed as a motor vehicle or a washing machine or a dish washer or a clothes dryer or a hair dryer or a vacuum cleaner or an exhaust air blower or an air intake assembly or a compressed-air-or electrical motor-operated tool.
  21. The use of a sound absorber (1) according to one of claims 1 through 18 for damping sound in the range of relatively high frequencies, for example, from approximately 900 Hz.
EP02701191A 2001-01-18 2002-01-15 Silencer with a plurality of resonance chambers Revoked EP1352172B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10102040A DE10102040A1 (en) 2001-01-18 2001-01-18 Silencer, for a motor exhaust or turbo charger air intake, has a hollow body at the component to be suppressed containing a number of parallel Helmholtz resonators
DE10102040 2001-01-18
PCT/DE2002/000094 WO2002057616A1 (en) 2001-01-18 2002-01-15 Silencer with a plurality of resonance chambers

Publications (2)

Publication Number Publication Date
EP1352172A1 EP1352172A1 (en) 2003-10-15
EP1352172B1 true EP1352172B1 (en) 2004-12-01

Family

ID=7670911

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02701191A Revoked EP1352172B1 (en) 2001-01-18 2002-01-15 Silencer with a plurality of resonance chambers

Country Status (4)

Country Link
US (1) US20040069563A1 (en)
EP (1) EP1352172B1 (en)
DE (2) DE10102040A1 (en)
WO (1) WO2002057616A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2295782A1 (en) 2009-09-11 2011-03-16 Hutchinson Silencing device for an intake line of a thermal engine and intake line incorporating a silencing device

Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10243884A1 (en) * 2002-09-21 2004-04-01 Mann + Hummel Gmbh Resonatorschalldämpfer
DE102004010037A1 (en) * 2004-03-02 2005-08-04 Daimlerchrysler Ag Exhaust gas turbocharger for internal combustion engine of motor vehicle, has exhaust gas turbines, and stabilizing cases arranged before inlets of respective superchargers to stabilize air flow of superchargers that is to be compressed
DE102004029221A1 (en) * 2004-06-16 2006-01-12 Geiger Technik Gmbh Acoustic damping device and device for conducting a fluid
US20070045042A1 (en) * 2005-08-25 2007-03-01 L&L Products, Inc. Sound reduction system with sound reduction chamber
US7870930B2 (en) * 2005-09-02 2011-01-18 Emcon Technologies Llc Exhaust system with external helmholtz resonator and associated method
ITMI20052297A1 (en) * 2005-11-30 2007-06-01 De Nora Elettrodi Spa ELECTROCHEMICAL TREATMENT OF SOLUTIONS WITH HEXAVALENT CHROME
FR2928705A1 (en) 2008-03-12 2009-09-18 Hutchinson Sa ACOUSTICAL ATTENUATION DEVICE FOR THE INTAKE LINE OF A THERMAL MOTOR, AND ADMISSION LINE INCORPORATING IT.
DE102008015353A1 (en) 2008-03-22 2009-09-24 Bosch Mahle Turbo Systems Gmbh & Co. Kg Loading device i.e. exhaust gas turbo charger, for motor vehicle, has sound absorber including chamber, where external wall is partially extended in axial direction and formed by housing of device
US7934581B2 (en) * 2009-01-30 2011-05-03 Eaton Corporation Broadband noise resonator
FR2945839B1 (en) * 2009-05-20 2012-10-26 Mann & Hummel Gmbh ACOUSTIC DEVICE FOR THE SOUNDPROOFING OF INTERNAL COMBUSTION ENGINES.
KR101033601B1 (en) 2009-06-03 2011-05-11 엘지전자 주식회사 hot air supplying apparatus and cloth treating apparatus
DE202009014112U1 (en) 2009-10-16 2010-01-07 Ti Automotive Engineering Centre (Heidelberg) Gmbh Silencer for a tubular body forming a cavity
EP2357330B1 (en) 2009-10-16 2015-08-19 TI Automotive Engineering Centre (Heidelberg) GmbH Cooling circuit with acoustic baffler for a tubular body forming a cavity
EP2327327A1 (en) * 2009-11-26 2011-06-01 Babyliss Faco S.A. Add-on silencer for hairdryer
JP5620690B2 (en) * 2010-02-15 2014-11-05 株式会社マキタ Blower
DE102012024512A1 (en) 2012-12-14 2014-06-18 Daimler Ag Silencer device for internal combustion engine of a motor vehicle, has acoustic resonator that is separately formed into suction duct, where construction element is integrated in internal combustion engine in partially opaque manner
DE102013215636A1 (en) * 2013-08-08 2015-02-12 Mahle International Gmbh Silencer
DE202014007986U1 (en) * 2014-10-01 2016-01-05 GM Global Technology Operations LLC (n. d. Gesetzen des Staates Delaware) silencer
US9650149B2 (en) * 2014-12-08 2017-05-16 Honeywell International Inc. Fire containment apparatuses for aircraft duct assemblies
JP6587521B2 (en) * 2015-11-19 2019-10-09 小島プレス工業株式会社 Vehicle silencer
JP2018128153A (en) * 2017-02-06 2018-08-16 三菱重工サーマルシステムズ株式会社 Refrigeration machine
JP6514727B2 (en) * 2017-03-08 2019-05-15 株式会社Ｓｕｂａｒｕ Silencer
JP7014584B2 (en) * 2017-12-12 2022-02-01 三菱重工サーマルシステムズ株式会社 A sound absorbing element for the refrigeration cycle system, a decompression unit with it, and a refrigeration cycle system.
DE102018116681A1 (en) * 2018-07-10 2020-01-16 Vorwerk & Co. Interholding Gesellschaft mit beschränkter Haftung Device and method for reducing the sound power of a sound source
CN110748410A (en) * 2019-11-11 2020-02-04 河北亚大汽车塑料制品有限公司 Vehicle silencer
CN114667390B (en) * 2019-11-20 2023-09-29 本田技研工业株式会社 Air inlet structure for vehicle
US20220016561A1 (en) * 2020-07-14 2022-01-20 Toledo Molding & Die, Llc Vehicle air filter housing with integrated broad band tuner
GB2616608A (en) * 2022-03-14 2023-09-20 Dyson Technology Ltd Noise attenuator

Family Cites Families (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1816109A (en) * 1928-11-06 1931-07-28 Maxim Silencer Co Silencer
DE732733C (en) * 1937-12-08 1943-03-10 Eberspaecher J Acoustic branch filter consisting of two or more resonators, especially for internal combustion engines
DE976032C (en) * 1949-11-22 1963-01-24 Eberspaecher J Silencer with branch filter and in-line filter
US3614859A (en) * 1969-11-17 1971-10-26 Ingersoll Rand Co Gas filter-silencer
US3910374A (en) * 1974-03-18 1975-10-07 Rohr Industries Inc Low frequency structural acoustic attenuator
US3955643A (en) * 1974-07-03 1976-05-11 Brunswick Corporation Free flow sound attenuating device and method of making
CA1027002A (en) * 1974-08-30 1978-02-28 Horst W.W. Hehmann Phased treatment noise suppressor for acoustic duct applications
US4174020A (en) * 1975-07-01 1979-11-13 Challis Louis A Acoustic treatment for fans
DK142710B (en) * 1977-11-10 1980-12-29 Elektronikcentralen Sound absorbing structure.
US4287962A (en) * 1977-11-14 1981-09-08 Industrial Acoustics Company Packless silencer
US4314621A (en) * 1979-03-07 1982-02-09 Caterpillar Tractor Co. Fluidborne noise attenuator
DE2947256C2 (en) * 1979-11-23 1984-09-13 Messerschmitt-Bölkow-Blohm GmbH, 8000 München Device for reducing exhaust or exhaust noise
US4360075A (en) * 1981-05-11 1982-11-23 General Motors Corporation Low back pressure exhaust silencer for diesel locomotives
US4645032A (en) * 1985-09-05 1987-02-24 The Garrett Corporation Compact muffler apparatus and associated methods
JPH088305Y2 (en) * 1987-09-07 1996-03-06 小島プレス工業株式会社 Silencer
US4979587A (en) * 1989-08-01 1990-12-25 The Boeing Company Jet engine noise suppressor
FI95747B (en) * 1991-01-17 1995-11-30 Valmet Paper Machinery Inc Mufflers for low frequencies for air ducts in paper mills
DE59209528D1 (en) * 1992-08-22 1998-11-19 Porsche Ag INTERNAL COMBUSTION ENGINE WITH AN INTAKE SYSTEM
DE19504223A1 (en) * 1995-02-09 1996-08-14 Volkswagen Ag Intake silencer for internal combustion engine
DE19615917A1 (en) * 1996-04-22 1997-10-30 Wolf Woco & Co Franz J Intake silencer and motor vehicle
DE19725003A1 (en) * 1997-06-13 1998-12-17 Philippron Jean Claude Muffler and soundproofing material
DE19818873C2 (en) * 1998-04-28 2001-07-05 Man B & W Diesel Ag Reciprocating internal combustion engine
US6231710B1 (en) * 1999-06-04 2001-05-15 The United States Of America As Represented By The Secretary Of The Air Force Method of making composite chambercore sandwich-type structure with inherent acoustic attenuation
US6695094B2 (en) * 2001-02-02 2004-02-24 The Boeing Company Acoustic muffler for turbine engine
US6752240B1 (en) * 2002-11-05 2004-06-22 Brunswick Corporation Sound attenuator for a supercharged marine propulsion device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2295782A1 (en) 2009-09-11 2011-03-16 Hutchinson Silencing device for an intake line of a thermal engine and intake line incorporating a silencing device
FR2950112A1 (en) * 2009-09-11 2011-03-18 Hutchinson ACOUSTICAL ATTENUATION DEVICE FOR THE INTAKE LINE OF A THERMAL MOTOR, AND ADMISSION LINE INCORPORATING IT
US8177024B2 (en) 2009-09-11 2012-05-15 Hutchinson Accoustic attenuation device for an intake line of a combustion engine and intake line incorporating same

Also Published As

Publication number Publication date
DE10102040A1 (en) 2002-07-25
EP1352172A1 (en) 2003-10-15
WO2002057616A1 (en) 2002-07-25
DE50201672D1 (en) 2005-01-05
US20040069563A1 (en) 2004-04-15

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