EP0962013B1 - Lambda/4-absorber mit einstellbarer bandbreite - Google Patents
Lambda/4-absorber mit einstellbarer bandbreite Download PDFInfo
- Publication number
- EP0962013B1 EP0962013B1 EP98900841A EP98900841A EP0962013B1 EP 0962013 B1 EP0962013 B1 EP 0962013B1 EP 98900841 A EP98900841 A EP 98900841A EP 98900841 A EP98900841 A EP 98900841A EP 0962013 B1 EP0962013 B1 EP 0962013B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- absorber
- absorber according
- resonators
- resonator
- sound
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
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
- G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
Definitions
- the invention relates to a ⁇ / 4 absorber Absorption of sound, such as that of machines, in particular of vehicles, is produced with a variety of tubular ⁇ / 4 resonators, the mouth of which is a sound reflecting Adjacent area.
- Helmholtz absorbers It is also known to sound absorbers from a variety differently dimensioned Helmholtz resonators build. Such Helmholtz absorbers are in the Practice not enforced for various reasons. In particular such Helmholtz absorbers are difficult to dimension and / or fabricate and unsuitable to to be used in heavily polluting environments can.
- This difference is essentially in the same time apparent mass and compressibility of the Air in the resonator and can be recognized in particular be that with the ⁇ / 4 resonators the resonance frequency is determined directly by the standing wave, its wavelength a quarter of the length of the tubular resonator is while the acoustic functioning and resonance of Helmholtz resonators using a spring-mass system must be described and determined.
- GB 2 038 410 is an acoustically effective lining for Aircraft engines are known in which a variety of Helmholtz resonators can be combined with ⁇ / 4 resonators. These resonators will packed as tightly as possible to achieve the highest possible absorption.
- the Openings of these resonators are with a perforated sheet or Non-woven fabric (with a relatively high acoustic resistance) covered to the acoustic coupling to the external sound field improve.
- DE 94 08 118 discloses a sound absorber with a plurality of tubular recesses or channels, which are in a porous Absorber material are used.
- the openings of the individual ⁇ / 4 tubes are covered with a porous foam, a nonwoven or a thin film.
- the cavities are with another sound-absorbing material completely or partially filled.
- Such a ⁇ / 4 absorber is described, for example, in WO 96/23294 and comprises a multiplicity of tubular resonators, the sound openings of which adjoin a surface, in such a way that the interaction zones (in which the incident sound wave and the standing waves formed in the individual resonators are located Waves destructively interfering) of the individual resonator openings are distributed as far as possible and at the same time do not substantially overlap.
- Such ⁇ / 4 resonators basically absorb in a narrow frequency range around their resonance frequency f 0 . The width of this frequency range depends on the quality factor Q of the resonators, respectively. on the size of the energy losses that occur during resonance.
- ⁇ / 4 absorbers can be embedded in any dense, reverberant material, such as, for example, metal, plastic, ceramic or glass.
- any dense, reverberant material such as, for example, metal, plastic, ceramic or glass.
- the energy losses are very small, ie the Q factor and the terminating impedance are very high. This leads to undesirably narrow resonance absorption curves.
- a ⁇ / 4 absorber with the features of claim 1.
- a heat sink is formed by any material which can absorb and dissipate heat from the temperature fluctuations in the air caused by pressure fluctuations. Those skilled in the field of noise protection are familiar with such materials.
- a plug made of closed-pore viscoelastic foam Another practical possibility is seen in the use of a plug made of closed-pore viscoelastic foam. Another possibility is to bring about energy losses in the mouth area by installing a - low - air flow resistance, for example a "grid". In the embodiment of a deep-drawn film with a cover plate, such a “grid” can be produced by not removing the end to be opened, but rather only perforating it.
- the present invention thus allows efficient for the first time ⁇ / 4 absorber industrial, i.e. inexpensive to manufacture.
- the present invention also enables Construction of multifrequency absorbers in a simple way, by forming a wider resonant frequency band several differently dimensioned ⁇ / 4 resonators with increased sound energy loss in the muzzle according to the invention and floor area can be combined.
- the principle of operation of the ⁇ / 4 absorber 1 according to the invention will be explained in more detail with reference to FIG. 1. It can be seen from this figure that the opening of the ⁇ / 4 resonator 2 lies in a sound-reflecting surface A.
- Z o is used to denote the characteristic impedance of the air.
- the sound impedance in the floor area 3 is referred to below as Z T and, in this simplified model, encompasses all sound energy losses inside the resonator (where Z T is proportional to the quality factor Q).
- an interaction zone S 1 is formed on the reflecting surface A, in which the incident sound wave destructively interferes with the standing wave formed in the resonator 2.
- this can be achieved by using soft, ie viscoelastic, closed-pore foams or other heat-exchanging materials in the bottom region of the ⁇ / 4 resonators, it being possible to choose all materials which lead to energy dissipation in the event of high pressure fluctuations.
- an impedance ratio Z T / Z o 25 results for 100% absorption. Since Z o corresponds to the characteristic impedance of the air, that is has a value of approx. 400 Ns / m 3 , the required sound impedance Z T in the floor area is approx. 25 * 400 Ns / m 3 . Unfortunately, such high impedance values are difficult to achieve today.
- the present invention also makes use of the knowledge that the following relationship applies to the resonance frequency for the impedance ratio Z T / Z o in the bottom region 3 and the impedance ratio Z o / Z mouth in the mouth region 4:
- Z T / Z O Z O / Zünd
- the frequency response respectively.
- the absorption characteristic of this resonator has a bandwidth B C of only 5.1%.
- FIG. 2b clearly shows the absorption behavior of the multifrequency absorber according to the invention.
- an absorption behavior is shown, as shown by curve V.
- the curve V results from the sum of the absorption characteristics S 1 , S 2 and S 3 generated by the individual narrowband absorbers.
- This curve V shows the disadvantages of the multifrequency absorbers created with conventional narrowband absorbers.
- This curve V follows the frequency response of the individual narrowband absorbers and drops sharply between the corresponding resonance frequencies f 1 , f 2 and f 3 , ie shows poor absorption in this intermediate range.
- the ⁇ / 4 absorbers according to the invention it is possible to create a broad absorption band W with a constantly high absorption capacity. It is clear from FIG. 2b that the ⁇ / 4 absorbers according to the invention have a larger bandwidth B than the conventional narrowband absorbers. In the case of multifrequency absorbers, this leads to significant overlaps in the absorption characteristics T 1 , T 2 and T 3 of the individual ⁇ / 4 absorbers in the areas lying between the individual resonance frequencies f 1 , f 2 and f 3 .
- Figures 3a, 3b, 3c and 3d show embodiments of the ⁇ / 4 absorber according to the invention. From Figure 3a it can be seen that the resonator 2 has a head part 5, in which has a variety of perforations, in particular Slots 6 is introduced. In addition to such a headboard 5 of such, can according to the invention a soft or in the bottom region 3 of the resonator 2 heat-exchanging material 7 may be attached (FIGS. 3a, 3c). In a further embodiment of the grid-like Headboard 5 can instead of slit-like perforations 6 holes 8 can also be provided (Figure 3b).
- a suitable energy-dissipating Materials 7 are materials to be considered which has a large heat capacity relative to air and a have as large a surface as possible, such as open-pore Foam with small cells, cotton-like fibers, granular marerial or porous ceramic material. As soft Materials come in closed pore, viscoelastic Foams or other materials in question at high Pressure fluctuations dissipate energy.
- Figure 4 shows another industrially in a simple manner Realizable multi-frequency absorber 9 with a variety different sized resonators 2.
- this one from one Nonwoven fabric or foam carrier layer 10, in which tubular depressions 11 are formed.
- These tubular depressions 11 can be with a Adhesive layer 12 to be coated on the one hand, the pores of the To close the carrier layer 10 in this area, and on the other hand, a cover film 13 on this carrier layer 10 to fix.
- the holes 8 or slots according to the invention 6 can be introduced into this cover sheet 13.
- the molded one Carrier layer 10 instead of being provided with a cover film 11, to be attached to a solid outer skin, e.g. a bonnet and the perforations 8, 6 in the deformed area 14 to mount the carrier layer 10.
- the ⁇ / 4 absorbers according to the invention can be simplified Manufacture wise industrially.
- these are extruded in a known manner, for example as extruded Plates with tube-like depressions, which are covered with a second plate become.
- these can be according to the invention Absorber also with the help of deep-drawing or Manufacture injection molding technology.
- In another form of production can directly corrugated material into which the perforations according to the invention introduced will be used.
- ⁇ / 4 resonators according to the invention in a suitable manner can be dimensioned and / or differently dimensioned ⁇ / 4 resonators to form a broadband absorber can be combined with each other.
- the resonators according to the invention individually, in Groups with similar resonators (monofrequency absorbers) or in groups with different dimensions Resonators (multifrequency absorbers) manufactured and used can be.
- the inventive Absorber also with conventional fibrous or foamed absorbers can be combined and in particular be coordinated so that this in the area of the absorption drop are effective against low frequencies.
- Your preferred application is in land and aircraft seen just like transformers, generators, Gearboxes or other machines of any kind.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
- Building Environments (AREA)
Description
Eine andere Möglichkeit besteht darin, im Mündungsbereich Energieverluste herbeizuführen, indem man einen - niedrigen - Luftströmungwiderstand einbaut, z.B. ein "Gitter". Bei der Ausführungsform aus einer tiefgezogenen Folie mit Abdeckplatte kann ein solches "Gitter" erzeugt werden, indem man das zu öffnende Ende nicht entfernt, sondern nur perforiert.
- Fig. 1:
- Prinzipschema zur Funktionsweise der λ/4-Resonatoren;
- Fig. 2a:
- Diagramm zum Absorptionsverhalten des erfindungsgemässen λ/4-Absorbers;
- Fig. 2b:
- Diagramm zum Absorptionsverhalten des erfindungsgemässen Multifrequenz-Absorbers;
- Fig. 3a:
- Ansicht einer ersten Ausführungsform eines Resonators mit geschlitztem Kopfteil für den erfindungsgemässen λ/4-Absorber;
- Fig. 3b:
- Ansicht einer zweiten Ausführungsform eines Resonators mit gelochtem Kopfteil für den erfindungsgemässen λ/4-Absorber;
- Fig. 3c:
- Ansicht einer weiteren Ausführungsform eines Resonators mit wärmetauschendem Material im Bodenteil für den erfindungsgemässen λ/4-Absorber;
- Fig. 3d:
- Ansicht einer besonderen Ausführungsform eines Resonators bei dem Mündungsbereich und Bodenbereich gegeneinander geneigt sind;
- Fig. 4:
- Querschnitt einer praktischen Ausführungsform des erfindungsgemässen λ/4-Absorbers.
Für obiges Beispiel, bei welchem S1/S2 = 25 gewählt worden ist, ergibt sich damit ein Impedanzverhältnis Zo/ZMünd = 25, resp. ZMünd = 1/25 * Zo = 1/25 * 400 Ns/m3. Dieser Wert entspricht etwa dem Strömungswiderstand, resp. der Schallimpedanz eines grobmaschigen Gitters (Fliegengitter) und kann damit in einfacher Weise, d.h. industriell realisiert werden.
Claims (10)
- λ/4-Absorber zur Absorption von Schall, wie er von Maschinen, insbesondere von Fahrzeugen, erzeugt wird, mit mehreren röhrchenförmigen λ/4-Resonatoren (2), deren Mündungen an eine schallreflektierende Fläche (A) angrenzen, wobei die Mündungen der einzelnen λ/4-Resonatoren (2) voneinander beabstandet sind, derart dass die Wechselwirkungszonen der einzelnen Resonatorenöffnungen, in welchen die auftreffende Schallwelle mit der im Resonator gebildeten stehenden Wellen destruktiv interferiert, möglichst flächendeckend ver-teilt sind und gleichzeitig nicht wesentlich überlappen, dadurch gekennzeichnet, dass zur Einstellung der Bandbreite (B) des Resonanzfrequenzgangs (C, D) der einzelnen λ/4-Resonatoren (2), diese mit Mitteln zur Änderung der Schallenergieverluste im Mündungsbereich (4) versehen sind, welche Mittel einen niedrigen Luftströmungswiderstand aufweisen, der etwa demjenigen eines grobmaschigen Gitters entspricht.
- λ/4-Absorber nach Anspruch 1, dadurch gekennzeichnet, dass die Mittel (6) zur Änderung des Energieverlustes im Mündungsbereich (4) ein Kopfteil (5) mit einer Mehrzahl schlitzförmiger Perforationen (6) umfassen.
- λ/4-Absorber nach Anspruch 1, dadurch gekennzeichnet, dass die Mittel (8) zur Änderung des Energieverlustes im Mündungsbereich (4) ein Kopfteil (5) mit einer Mehrzahl lochförmiger Perforationen (8) umfassen.
- λ/4-Absorber nach Anspruch 1, dadurch gekennzeichnet, dass die Mittel (6, 8) zur Änderung des Energieverlustes im Mündungsbereich (4) ein gitterartiges Kopfteil (5) umfassen.
- λ/4-Absorber nach einem der Ansprüche 2 bis 4, dadurch gekennzeichnet, dass das Kopfteil (5) integrierender Bestandteil des λ/4-Absorbers (2) ist.
- λ/4-Absorber nach Anspruch 1, dadurch gekennzeichnet, dass weitere Mittel (7) zur Änderung des Energieverlustes im Bodenbereich (3) des λ/4-Resonators (2) vorgesehen sind.
- λ/4-Absorber nach Anspruch 6, dadurch gekennzeichnet, dass die Mittel (7) zur Änderung des Energieverlustes im Bodenbereich (3) ein im Bodenteil des Resonators (2) vorgesehenes weiches und/oder wärmetauschendes Material umfassen.
- λ/4-Absorber nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass der Mündungsbereich (4) und der Bodenbereich (3) gegeneinander geneigt sind.
- Verwendung eines λ/4-Absorbers nach einem der Ansprüche 1 bis 8 als Multifrequenz-Absorber.
- Verwendung eines λ/4-Absorbers nach einem der Ansprüche 1 bis 8 als Monofrequenz-Absorber.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH00389/97A CH691942A5 (de) | 1997-02-19 | 1997-02-19 | Lambda/4-Absorber mit einstellbarer Bandbreite. |
CH38997 | 1997-02-19 | ||
PCT/CH1998/000041 WO1998037541A1 (de) | 1997-02-19 | 1998-02-04 | μ/4-ABSORBER MIT EINSTELLBARER BANDBREITE |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0962013A1 EP0962013A1 (de) | 1999-12-08 |
EP0962013B1 true EP0962013B1 (de) | 2002-01-02 |
Family
ID=4185895
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP98900841A Expired - Lifetime EP0962013B1 (de) | 1997-02-19 | 1998-02-04 | Lambda/4-absorber mit einstellbarer bandbreite |
Country Status (7)
Country | Link |
---|---|
US (1) | US6167985B1 (de) |
EP (1) | EP0962013B1 (de) |
JP (1) | JP3242931B2 (de) |
AR (1) | AR011841A1 (de) |
CH (1) | CH691942A5 (de) |
DE (1) | DE59802792D1 (de) |
WO (1) | WO1998037541A1 (de) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE202010006419U1 (de) | 2010-05-04 | 2010-09-02 | Emico Gmbh | Breitbandig dämpfende Vorrichtung zur Schalldämpfung bei Industrieeinrichtungen, Großanlagen oder Maschinen |
CN102013251A (zh) * | 2009-09-07 | 2011-04-13 | 雅马哈株式会社 | 声学共鸣装置 |
WO2024153808A1 (en) * | 2023-01-20 | 2024-07-25 | Hitachi Energy Ltd | Device for reducing noise caused by a transformer and system |
Families Citing this family (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE508526C2 (sv) * | 1997-02-12 | 1998-10-12 | Saab Automobile | Förfarande och anordning för ljuddämpning i hjul |
US6821597B1 (en) | 1999-03-10 | 2004-11-23 | Magee Rieter Automotive Systems | Method for manufacturing a sound insulating structure and the structure produced thereby |
JP3736790B2 (ja) | 2000-04-21 | 2006-01-18 | 三菱重工業株式会社 | アクティブ遮音壁 |
AU2002237887A1 (en) * | 2001-02-09 | 2002-08-28 | Dow Global Technologies Inc. | Sound absorbing foam |
US6648100B2 (en) | 2001-10-24 | 2003-11-18 | Lear Corporation | Method of tuning acoustical absorption in a vehicle interior |
US7029242B2 (en) * | 2003-11-14 | 2006-04-18 | Tecumseh Products Company | Hermetic compressor with one-quarter wavelength tuner |
US7497301B2 (en) * | 2005-01-27 | 2009-03-03 | Fleetguard, Inc. | Tubular acoustic silencer |
US10072256B2 (en) * | 2006-05-22 | 2018-09-11 | Abbott Products Gmbh | Process for separating and determining the viral load in a pancreatin sample |
US8136630B2 (en) * | 2007-06-11 | 2012-03-20 | Bonnie Schnitta | Architectural acoustic device |
JP5326472B2 (ja) * | 2007-10-11 | 2013-10-30 | ヤマハ株式会社 | 吸音構造 |
EP2085962A2 (de) * | 2008-02-01 | 2009-08-05 | Yamaha Corporation | Schallabsorbierende Struktur und Fahrzeugkomponente mit schallabsorbierenden Eigenschaften |
US20090223738A1 (en) * | 2008-02-22 | 2009-09-10 | Yamaha Corporation | Sound absorbing structure and vehicle component having sound absorption property |
US8006802B2 (en) * | 2008-09-02 | 2011-08-30 | Yamaha Corporation | Acoustic structure and acoustic room |
JP5691197B2 (ja) * | 2009-03-06 | 2015-04-01 | ヤマハ株式会社 | 音響構造体、プログラムおよび設計装置 |
ITPI20100033A1 (it) * | 2010-03-23 | 2011-09-24 | Federico Nardini | Dispositivo fonoassorbente particolarmente per barriere antirumore. |
JP5958523B2 (ja) * | 2010-05-17 | 2016-08-02 | ヤマハ株式会社 | 音響構造体 |
US8393437B2 (en) * | 2011-02-15 | 2013-03-12 | Westinghouse Electric Company Llc | Noise and vibration mitigation system for nuclear reactors employing an acoustic side branch resonator |
JP2013015118A (ja) * | 2011-07-06 | 2013-01-24 | Toyota Boshoku Corp | 吸音構造体 |
JP5810884B2 (ja) * | 2011-12-15 | 2015-11-11 | ヤマハ株式会社 | 音響構造体 |
FR3010225B1 (fr) * | 2013-08-29 | 2016-12-30 | Centre Nat Rech Scient | Panneau acoustique absorbant |
JP6327932B2 (ja) * | 2014-05-07 | 2018-05-23 | 大成建設株式会社 | ヘルムホルツ共鳴を利用した吸音器 |
US9618151B2 (en) | 2015-02-26 | 2017-04-11 | Adriaan DeVilliers | Compact modular low resistance broadband acoustic silencer |
US11047304B2 (en) * | 2018-08-08 | 2021-06-29 | General Electric Company | Acoustic cores with sound-attenuating protuberances |
DE102020100445A1 (de) | 2020-01-10 | 2021-07-15 | Viessmann Werke Gmbh & Co Kg | Wärmetechnisches Gerät |
US11854522B2 (en) * | 2020-11-10 | 2023-12-26 | Toyota Motor Engineering & Manufacturing North America, Inc. | Sound absorbing structure having one or more acoustic scatterers attached to a transparent panel |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4160491A (en) * | 1978-07-25 | 1979-07-10 | Bridgestone Tire Co., Ltd. | Perlite sound absorbing plate and sound insulating wall composed of the same |
GB2038410B (en) * | 1978-12-27 | 1982-11-17 | Rolls Royce | Acoustic lining utilising resonance |
US4441578A (en) * | 1981-02-02 | 1984-04-10 | Rohr Industries, Inc. | Encapsulated bulk absorber acoustic treatments for aircraft engine application |
DE3133844A1 (de) * | 1981-08-27 | 1983-03-17 | Intreprinderea de Prefabricate din Beton "Granitul", Bucuresti | Fertigteilelement zur schalldaemmung |
FR2615994B1 (fr) * | 1987-05-25 | 1989-07-28 | Alsthom | Revetement de paroi absorbant les ondes acoustiques en milieu liquide |
JPH02122923A (ja) * | 1988-11-01 | 1990-05-10 | Fuji Heavy Ind Ltd | 複合材パネルおよびその製造方法 |
US5457291A (en) * | 1992-02-13 | 1995-10-10 | Richardson; Brian E. | Sound-attenuating panel |
DE9408118U1 (de) * | 1994-05-17 | 1995-09-14 | M. Faist GmbH & Co KG, 86381 Krumbach | Schallabsorber |
CH690143A5 (de) * | 1995-01-27 | 2000-05-15 | Rieter Automotive Int Ag | Lambda/4-Schallabsorber. |
JP3119193B2 (ja) * | 1997-03-07 | 2000-12-18 | 日産自動車株式会社 | 遮音板構造 |
-
1997
- 1997-02-19 CH CH00389/97A patent/CH691942A5/de not_active IP Right Cessation
-
1998
- 1998-02-04 EP EP98900841A patent/EP0962013B1/de not_active Expired - Lifetime
- 1998-02-04 DE DE59802792T patent/DE59802792D1/de not_active Expired - Fee Related
- 1998-02-04 JP JP53612098A patent/JP3242931B2/ja not_active Expired - Fee Related
- 1998-02-04 WO PCT/CH1998/000041 patent/WO1998037541A1/de active IP Right Grant
- 1998-02-04 US US09/355,636 patent/US6167985B1/en not_active Expired - Fee Related
- 1998-02-19 AR ARP980100742A patent/AR011841A1/es unknown
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102013251A (zh) * | 2009-09-07 | 2011-04-13 | 雅马哈株式会社 | 声学共鸣装置 |
DE202010006419U1 (de) | 2010-05-04 | 2010-09-02 | Emico Gmbh | Breitbandig dämpfende Vorrichtung zur Schalldämpfung bei Industrieeinrichtungen, Großanlagen oder Maschinen |
WO2011138004A1 (de) | 2010-05-04 | 2011-11-10 | Emico Gmbh | Breitbandig dämpfende vorrichtung zur schalldämpfung bei industrieeinrichtungen, grossanlagen oder maschinen |
WO2024153808A1 (en) * | 2023-01-20 | 2024-07-25 | Hitachi Energy Ltd | Device for reducing noise caused by a transformer and system |
Also Published As
Publication number | Publication date |
---|---|
EP0962013A1 (de) | 1999-12-08 |
WO1998037541A1 (de) | 1998-08-27 |
US6167985B1 (en) | 2001-01-02 |
JP2001512582A (ja) | 2001-08-21 |
JP3242931B2 (ja) | 2001-12-25 |
AR011841A1 (es) | 2000-09-13 |
DE59802792D1 (de) | 2002-02-28 |
CH691942A5 (de) | 2001-11-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0962013B1 (de) | Lambda/4-absorber mit einstellbarer bandbreite | |
DE10347084B4 (de) | Abstimmbare, den Schall absorbierende, und die Luft filternde Dämpfungseinrichtung und Herstellungsverfahren | |
EP0806030B1 (de) | l/4-SCALLABSORBER | |
EP1562743B1 (de) | Schallisolierender hitzeschutzschild | |
EP1697923B1 (de) | Luftschallabsorbierendes bauteil | |
DE4414566C2 (de) | Luftschalldämpfer | |
EP0677429B1 (de) | Schallabsorber für Kraftfahrzeuge | |
EP0454949B1 (de) | Luftschall absorbierendes Formteil | |
DE69902276T2 (de) | Mikroperforierte polymerfolie zur schalldämpfung and schalldämpfer der diese verwendet | |
DE112005003232T5 (de) | Schallschluckende Struktur | |
EP0531761A1 (de) | Absorber | |
WO1996008812A1 (de) | Schichtenabsorber zum absorbieren von akustischen schallwellen | |
DE10228395C1 (de) | Schall-Absorber | |
DE602004002864T2 (de) | Bauteil zur geräuschmindenderung, insbesondere bodenplatte eines fahrzeuges | |
EP0683480B1 (de) | Schallabsorber | |
DE102004050649A1 (de) | Schallabsorbierender Hitzeschild | |
EP0605784B1 (de) | Akustikplatte | |
DE60118221T2 (de) | Schallabsorptionsvorrichtung | |
EP3246479B1 (de) | Absorbereinheit zum absorbieren von schall | |
DE3412432A1 (de) | Schallabsorbierendes bauelement | |
DE2437947C3 (de) | Anordnung zur Absorption von Luftschall | |
DE102019128209B4 (de) | Schallabsorbierende Vorrichtung mit Noppenfolienverbund und Verwendung | |
DE4416361A1 (de) | Lamellenabsorber | |
DE2609872A1 (de) | Schalldaempfer fuer stroemungskanaele | |
EP1024054A2 (de) | Fahrzeug-Formhimmel |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 19990615 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): CH DE FR GB IT LI |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
RTI1 | Title (correction) |
Free format text: LAMBDA/4 ABSORBER WITH ADJUSTABLE BAND WIDTH |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
17Q | First examination report despatched |
Effective date: 20010625 |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): CH DE FR GB IT LI |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20020122 Year of fee payment: 5 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 20020222 Year of fee payment: 5 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20020227 Year of fee payment: 5 |
|
REF | Corresponds to: |
Ref document number: 59802792 Country of ref document: DE Date of ref document: 20020228 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20020318 Year of fee payment: 5 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: NV Representative=s name: GRAF, SEIFERT + PARTNER PATENTANWAELTE |
|
GBT | Gb: translation of ep patent filed (gb section 77(6)(a)/1977) |
Effective date: 20020328 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20030204 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20030228 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20030228 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20030902 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee | ||
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20031031 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20050204 |