DK147533B - SCENE Muffler - Google Patents
SCENE Muffler Download PDFInfo
- Publication number
- DK147533B DK147533B DK110576AA DK110576A DK147533B DK 147533 B DK147533 B DK 147533B DK 110576A A DK110576A A DK 110576AA DK 110576 A DK110576 A DK 110576A DK 147533 B DK147533 B DK 147533B
- Authority
- DK
- Denmark
- Prior art keywords
- attenuation
- muffler
- sub
- scenery
- scenes
- Prior art date
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/02—Energy absorbers; Noise absorbers
-
- 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
Description
167533167533
Opfindelsen angår en kulisselyddæmper af den i kra-5 vets indledning angivne art.The invention relates to a scenic silencer of the type specified in the preamble of the claim.
Hovedstøjkilden i ventilations- og klimaanlæg er ventilatoren. Lydafgivelsesspektret for ventilatorstøj har sit højeste punkt i et lavfrekvent område mellem 10 100 og 500 Hz. Ved højere frekvenser falder støjin tensiteten derimod.The main source of noise in ventilation and air conditioning systems is the fan. The sound emission spectrum of fan noise has its highest point in a low frequency range between 10,100 and 500 Hz. At higher frequencies, on the other hand, the noise intensity decreases.
På grund af lyddæmpningen i kanalsystemet på grund af ombøjninger, afgreninger og mundingsreflektioner, 15 bliver ventilatorstøjen tildels nedsat, men der vil især i frekvensområdet 200 - 500 Hz ofte alligevel være et for stort lydniveau hidrørende fra ventilatoren.Due to the sound attenuation in the duct system due to deflections, branches and orifice reflections, the fan noise is partly reduced, but especially in the frequency range 200 - 500 Hz there will often still be too large a sound level originating from the fan.
20 Af denne grund kræves der i de fleste tilfælde en y-derligere dæmpning, overvejende i et frekvensområde mellem 200 og 500 Hz.For this reason, in most cases an additional attenuation is required, predominantly in a frequency range between 200 and 500 Hz.
Ved de kendte kulisselyddæmpere af den omhandlede art 25 er dæmpningens maksimum bestemt af kulissens tykkelse. Ved de kendte kulisser, der på begge sider er udfyldt med lydabsorberende materiale, ligger den maksimale dæmpning ved en frekvens f = c/2 x d. Herved betegner c lydhastigheden og d kulissetykkelsen.In the case of the known scenic silencers of the type 25 in question, the maximum attenuation is determined by the thickness of the scenery. At the known scenes, which on both sides are filled with sound-absorbing material, the maximum attenuation is at a frequency f = c / 2 x d. Here, c denotes the speed of sound and d denotes the stage thickness.
3030
Ved lavere frekvenser falder dæmpningen stærkt. Ved de sædvanlige kulissetykkelser ligger den maksimale dæmpning derfor ved omkring 1000 - 2000 Hz. For at opnå den påkrævede dæmpning i området på 200 - 147533 2 1 500 Hz, må kulisselængden derfor dimensioneres meget stor, hvorved dæmpningen i det højfrekvente område bliver unødig høj, hvilket er fordyrende for lyddæmperen.At lower frequencies, the attenuation decreases sharply. At the usual backdrop thicknesses, the maximum attenuation is therefore around 1000 - 2000 Hz. In order to achieve the required attenuation in the range of 200 - 147533 2 1 500 Hz, the stage length must therefore be dimensioned very large, whereby the attenuation in the high-frequency range becomes unnecessarily high, which is expensive for the silencer.
55
Pra fransk patent nr. 2 058 849 kendes en kulissedæmper opbygget af bl.a. krumme delkulisser, der på den ene side har en ikke-perforeret, gennemgående og lyddæmpende væg, og som på den anden side har en 10 perforeret væg. Delkulisserne er således anbragt efter hinanden, at de perforerede sider støder op til hinanden, og de ikke-perforererede sider støder op til hinanden, således at der dannes strømningskanaler med krumme dele, der på den ene side har lukkede væg-15 ge og på den anden side perforerede vægge på begge sider. Denne lyddæmper vil ikke have særskilt god dæmpning af det kritiske frekvensområde 200 - 500 Hz, og vil således også skulle bygges uhensigtsmæssigt lang med store ulemper såsom omkostninger, trykfald 20 og pladsoptagelse til følge.French Patent No. 2,058,849 discloses a backdrop damper constructed of i.a. curved sub-scenery, which on the one hand has a non-perforated, continuous and sound-absorbing wall, and which on the other hand has a 10 perforated wall. The sub-scenes are arranged one after the other so that the perforated sides are adjacent to each other and the non-perforated sides are adjacent to each other, so that flow channels are formed with curved parts which on one side have closed walls and on the other side perforated walls on both sides. This muffler will not have particularly good attenuation of the critical frequency range 200 - 500 Hz, and will thus also have to be built inappropriately long with major disadvantages such as cost, pressure drop 20 and space consumption as a result.
Formålet med opfindelsen er at angive en absorptionsdæmper af kulissetype til ventilations- og klimaanlæg, ved hvilket den optimale dæmpning ligger i fre-25 kvensområdet mellem 200 og 500 Hz, men uden en unødig høj dæmpning i det højfrekvente område, hvorfor lyddæmperen tillige får en minimal byggelængde.The object of the invention is to provide a stage-type absorption attenuator for ventilation and air conditioning systems, in which the optimum attenuation is in the frequency range between 200 and 500 Hz, but without an unnecessarily high attenuation in the high-frequency range, so that the attenuator also has a minimal construction length.
Dette opnås ifølge opfindelsen ved, at lyddæmperen 30 er udformet som angivet i kravets kendetegnende del.This is achieved according to the invention in that the muffler 30 is designed as stated in the characterizing part of the claim.
Herved opnås den overraskende virkning, at netop de - lave frekvenser dæmpes kraftigere end de højere.This achieves the surprising effect that precisely the low frequencies are attenuated more strongly than the higher ones.
Dæmpningen ved højere frekvenser er ikke større, end det er nødvendigt for effektivt at dæmpe støjen fra 3 147533 1 en ventilator.The attenuation at higher frequencies is not greater than is necessary to effectively attenuate the noise from a fan.
Opfindelsen forklares herefter nærmere under henvisning til tegningen, på hvilken 5 fig. 1 viser en kulisselyddæmper af sædvanlig byggemåde i et skematisk længdesnit, fig. 2 delkulisser ved lyddæmperen ifølge opfin-10 delsen i forskellige udførelser, ligeledes i skematisk længdesnit, fig. 3 i perspektiv flere ved siden af hinanden anbragte delkulisser, 15 fig. 4 i grafisk fremstilling lydniveauer i afhængighed af frekvensen for ventilatorstøj i ventilations- og klimaanlæg, ventilatorstøj efter egendæmpning i kanalsystemet, det mak-20 simalt tilladelige støjniveau i rum og sæd vanlige lyddæmpekulisser, fig. 5 i grafisk fremstilling dæmpningen i afhængighed af frekvensen.The invention will now be explained in more detail with reference to the drawing, in which fig. 1 shows a scenic muffler of the usual construction in a schematic longitudinal section, fig. 2 sub-scenes at the muffler according to the invention in different embodiments, also in schematic longitudinal section, fig. 3 is a perspective view of several sub-scenes arranged next to each other, FIG. Fig. 4 in graphical representation sound levels depending on the frequency of fan noise in ventilation and air conditioning systems, fan noise after self-attenuation in the duct system, the maximum permissible noise level in rooms and normal attenuation scenery, fig. 5 in graphical representation the attenuation depending on the frequency.
25 I fig. 1 er vist den gængse byggemåde for kulisselyd-dæmpere, ved hvilken flere ved siden af hinanden stående kulisser 1 er indsat i et kanalhus 2 med kvadratisk eller rektangulært tværsnit. Tykkelsen af kulisserne 1 30 er betegnet med d og deres afstand fra hinanden med s.In FIG. 1 shows the common construction method for scenic silencers, in which several adjacent scenes 1 are inserted in a channel housing 2 with a square or rectangular cross-section. The thickness of the scenes 1 30 is denoted by d and their distance from each other by s.
Ved kanalvæggen fås der en afstand s/2. Længden af ku-· lisserne er betegnet med 1. Disse kendte kulisser 1 har en omløbende ramme la, der er indfattet med et absorptionsmateriale 3 af f.eks. mineraluld.At the channel wall a distance s / 2 is obtained. The length of the scenery is denoted by 1. These known scenery 1 have a circumferential frame 1a, which is framed with an absorbent material 3 of e.g. mineral wool.
4 147533 1 Lyddæmperen gennemstrømmes i retning af pile a, og mellemrummene mellem de enkelte kulisser danner parallelt med hinanden forløbende strømningskanaler 4.The silencer is flowed through in the direction of arrows a, and the spaces between the individual scenes form flow channels running parallel to each other 4.
5 Ved sådanne kendte kulisselyddæmpere er kun den halve tykkelse d/2 i kulisserne 1 virksom, så at der ved lave frekvenser fås en lav dæmpning. Dette medfører, at lyddæmperen må udformes forholdsvis lang for at opnå en tilstrækkelig dæmpning også af de forholdsvis 10 lave frekvenser.With such known scenic silencers, only half the thickness d / 2 in the scenery 1 is effective, so that at low frequencies a low attenuation is obtained. This means that the muffler must be designed relatively long in order to obtain a sufficient attenuation also of the relatively low frequencies.
I modsætning hertil består kulisserne 5 ved lyddæmperen ifølge opfindelsen, som det fremgår af fig. 2, af mindre delkulisser 6, der i strømningsretning er an-15 bragt på vilkårlig måde efter hinanden.In contrast, the scenery 5 of the muffler according to the invention, as shown in fig. 2, of smaller sub-scenes 6, which are arranged in the flow direction in a random manner one after the other.
Hver delkulisse 6 er opbygget således, at den kun er åben på en af de to sider, der vender mod den tilstrømmende gas. Delkulisserne 6 har desuden U-profil og kan 20 fyldes med absorptionsmateriale 7.Each sub-stage 6 is constructed so that it is only open on one of the two sides facing the inflowing gas. The sub-scenes 6 also have a U-profile and can be filled with absorption material 7.
Som det fremgår af såvel fig. 2 som også af fig. 3, er delkulisserne 6 anbragt skiftevis fortsat 180° i forhold til hinanden og efter hinanden og er sammen-25 fattet ved hjælp af U-formede hoved- og fodskinner henholdsvis 8 og 9 til en samlet kulisse 5. De samlede kulisser 5 er derefter, ligesom ved den kendte udførelse i fig. 1, indsættelige i en kanal 2, hvorved lyddæmperen dahnes. Ved lyddæmperen ifølge opfindelsen 30 er ikke mere de halve, men den fulde kulissetykkelse 10 akustisk virksom, så at der opnås forholdsvis høje dæmpningsværdier også ved lave frekvenser.As can be seen from both FIG. 2 as also of fig. 3, the partial scenarios 6 are arranged alternately still 180 ° relative to each other and one after the other and are summarized by means of U-shaped head and foot rails 8 and 9, respectively, into a single scenery 5. The assembled scenery 5 is then as in the known embodiment in fig. 1, insertable into a channel 2, whereby the muffler dahnes. With the muffler according to the invention 30, no longer the half, but the full stage thickness 10 is acoustically effective, so that relatively high attenuation values are obtained even at low frequencies.
Delkulisserne 6 kan udføres på forskellige måder. En- 5 147533 1 kelte typer fremgår af fig. 2.The sub-scenes 6 can be made in different ways. Some types are shown in FIG. 2.
A betegner en delkulisse, der kan anbringes ved begyndelsen eller ved enden af en samlet kulisse. De frie 5 sidekanter 6a er afrundet, hvorved der fås gunstigere strømningsegenskaber, og lavt tryktab. De andre sidekanter 6b er derimod skarpkantede.A denotes a sub-backdrop that can be placed at the beginning or at the end of an overall backdrop. The free side edges 6a are rounded, whereby more favorable flow properties are obtained, and low pressure loss. The other side edges 6b, on the other hand, are sharp-edged.
B betegner en type delkulisse, der kan anbringes ved 10 midten af en samlet delkulisse. Denne type B har kun skarpkantede sidekanter 6b.B denotes a type of sub-backdrop that can be placed at the center of an overall sub-backdrop. This type B has only sharp-edged side edges 6b.
C betegner en type delkulisse, der også kan anvendes som endedelkulisse. Denne type C er konisk indsnævret.C denotes a type of sub-backdrop that can also be used as an end sub-backdrop. This type C is conically narrowed.
1515
Af fig. 2 kan man se, at man hensigtsmæssigt ved en lyddæmper af to delkulisser blot anvender to typer A.From fig. 2, it can be seen that it is expedient to use only two types A with a muffler of two sub-scenes.
Drejer det sig om tre delkulisser, anvendes der ved enderne to kulisser af type A og i midten en af type 20 B. Anvendes der fire kulisser, bruger man igen to af type A ved enderne og ved midten to af type B. Endelig kan man også som endedelkulisser, som det ligeledes fremgår af fig. 2, anvende typen C.In the case of three sub-scenarios, two scenarios of type A are used at the ends and one of type 20 B in the middle. If four scenarios are used, two of type A are used again at the ends and two of type B. also as end part scenery, as also appears from fig. 2, use type C.
25 I fig. 4 vises lydfrekvensspektret for ventilatorstøj ved spektrum 1. Det har sit højeste punkt i et lavfrekvent område mellem 100 og 500 Hz og falder hen imod de høje frekvenser. Ved spektrum 2 vises ventilatorstøjen efter nedsættelse på grund af egendæmpning 30 i kanalsystemets ombøjninger, afgreninger og mundings-reflektioner. Det maksimalt tilladelige støjniveau i rum vises ved spektrum 3. Spektrum 4 fremkommer ved brug af kendte kulisselyddæmpere, hvis dæmpningsmaksimum bestemmes af kulissens tykkelse til at opfylde 6 147533 1 kravene til støjniveau i rum.In FIG. 4 shows the sound frequency spectrum of fan noise at spectrum 1. It has its highest point in a low frequency range between 100 and 500 Hz and decreases towards the high frequencies. At spectrum 2, the fan noise after reduction due to self-attenuation 30 is shown in the deflections, branches and orifice reflections of the duct system. The maximum permissible noise level in rooms is shown by spectrum 3. Spectrum 4 is obtained using known scenic mufflers, the attenuation maximum of which is determined by the thickness of the scenery to meet the requirements for noise level in rooms.
Forskellen i de akustiske egenskaber ved lyddæmperen ifølge opfindelsen i forhold til de kendte lyddæmpere 5 er vist ved den grafiske fremstilling i fig. 5· En med 7 betegnet kurve viser den fornødne dæmpning. Det vil ses, at maksimum ligger omtrent ved 250 Hz. Dette maksimum opnås såvel ved den gængse lyddæmper, kurve 6, som også ved lyddæmperen ifølge opfindelsen, kurve 10 5s men ved den sidste lyddæmper opnås maksimum ved en kulisselængde, der er omkring 30$ mindre end ved de kendte lyddæmpere. Medens der ved de kendte lyddæmpere unødigt sker en ekstrem høj dæmpning i det højfrekvente område, hvad der kun er muligt ved anvendelse 15 af meget materiale, vil dæmpningskurven ved lyddæmperen ifølge opfindelsen svare væsentligt bedre til den krævede dæmpning.The difference in the acoustic properties of the muffler according to the invention in relation to the known mufflers 5 is shown by the graphic representation in fig. 5 · A curve denoted by 7 shows the required attenuation. It will be seen that the maximum is approximately at 250 Hz. This maximum is achieved both with the standard muffler, curve 6, and also with the muffler according to the invention, curve 10 5s, but with the last muffler the maximum is achieved with a backdrop length which is about 30 $ less than with the known mufflers. While with the known silencers an extremely high attenuation takes place in the high-frequency range, which is only possible with the use of a lot of material, the attenuation curve of the silencer according to the invention will correspond significantly better to the required attenuation.
Fordelene ved lyddæmperen ifølge opfindelsen lader 20 sig sammenfatte på følgende måde: 1. Hele kulissetykkelsen d er akustisk virksom, hvorved man opnår forholdsvis høje dæmpningsværdier ved lave frekvenser.The advantages of the muffler according to the invention can be summarized as follows: 1. The entire stage thickness d is acoustically effective, whereby relatively high attenuation values are obtained at low frequencies.
25 2. Lyddæmperen kan sammensættes efter et byggekasse- princip i enhver ønsket længde af delkulisser.25 2. The muffler can be assembled according to a building box principle in any desired length of sub-scenes.
3· På grund af den strømningstekniske gunstigt formede udførelse af typen A optræder der små tryktab.3 · Due to the flow-technically favorable design of type A, small pressure losses occur.
4. En yderligere reduktion af tryktabet er mulig ved 30 anvendelse af delkulisser af type C på afstrømningssiden.A further reduction of the pressure loss is possible by using type C sub-scenes on the run-off side.
5. Alle delkulisser fastholdes blot ved hjælp af en hoved- og en fodskinne. Derved kan man fremstille næsten vilkårlige kulisselængder.5. All sub-scenery is maintained simply by means of a head rail and a foot rail. This allows you to make almost any length of scenery.
7 147533 1 6. På grund af formgivningen af delkulisserne har disse en stor stabilitet, så at der kan anvendes meget tynde blikplader til deres fremstilling.7 147533 1 6. Due to the design of the sub-scenery, these have a great stability, so that very thin tin plates can be used for their production.
7- Til stabiliteten af absorptionsmåtterne kan der 5 stilles lavere krav, da de kan sammenfattes i forholdsvis små flade enheder.7- For the stability of the absorption mats, 5 lower requirements can be set, as they can be summarized in relatively small flat units.
8. Der kan anvendes absorptionsmaterialer med lav rumvægt, hvilke er billige, da det til opnåelse af store dæmpningsværdier i det lavfrekvente område er 10 hensigtsmæssigt at anvende absorptionsmåtter med små impedanser.8. Absorption materials with a low bulk density can be used, which are inexpensive, since it is expedient to use absorption mats with small impedances in order to obtain large attenuation values in the low-frequency range.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2513946A DE2513946C2 (en) | 1975-03-29 | 1975-03-29 | Splitter silencer |
DE2513946 | 1975-03-29 |
Publications (3)
Publication Number | Publication Date |
---|---|
DK110576A DK110576A (en) | 1976-09-30 |
DK147533B true DK147533B (en) | 1984-09-17 |
DK147533C DK147533C (en) | 1985-08-12 |
Family
ID=5942687
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DK110576A DK147533C (en) | 1975-03-29 | 1976-03-15 | SCENE Muffler |
Country Status (15)
Country | Link |
---|---|
AT (1) | AT349695B (en) |
AU (1) | AU505475B2 (en) |
BE (1) | BE840133A (en) |
BR (1) | BR7601837A (en) |
CH (1) | CH601745A5 (en) |
DE (1) | DE2513946C2 (en) |
DK (1) | DK147533C (en) |
ES (1) | ES446442A1 (en) |
FR (1) | FR2306395A1 (en) |
GB (1) | GB1512164A (en) |
IT (1) | IT1202986B (en) |
NL (1) | NL7602185A (en) |
NO (1) | NO145736C (en) |
SE (1) | SE410217C (en) |
ZA (1) | ZA761614B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DK157044B (en) * | 1978-10-13 | 1989-10-30 | Leif Ingemar Lind | STUDY DISTRIBUTION BODY INCLUDED IN AN AIR SUPPLY BODY |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2834267A1 (en) * | 1978-08-04 | 1980-02-28 | Colt Int Gmbh | Sound absorber esp. for ventilation ducts - uses sound-absorbing elements in case slidable in slots in opposite walls, and in parallel to each other |
DE3224241A1 (en) * | 1981-07-15 | 1983-02-24 | VEB Kombinat Luft- und Kältetechnik, DDR 8080 Dresden | Component for producing sound-absorbing surfaces and ducts |
SE450656B (en) * | 1982-05-14 | 1987-07-13 | Bahco Ventilation Ab | Muffler for ventilation ducts or ventilation equipment |
DE3230535C2 (en) * | 1982-08-17 | 1986-08-28 | Oskar Gerber Schall- und Schwingungstechnik GmbH, 4600 Dortmund | Silencer for a gas flow |
DE8327189U1 (en) * | 1983-09-22 | 1983-12-29 | Rox Lufttechnische Gerätebau GmbH, 5000 Köln | DEVICE SILENCER |
GB8503243D0 (en) * | 1985-02-08 | 1985-03-13 | Colchester Woods | Air duct silencer |
DE9207092U1 (en) * | 1992-05-26 | 1992-08-20 | Gebrueder Trox, Gmbh, 4133 Neukirchen-Vluyn, De | |
SE511627C2 (en) * | 1997-11-03 | 1999-11-01 | Stifab Farex Ab | Muffler baffle for rectangular vents |
SE511628C2 (en) * | 1997-11-10 | 1999-11-01 | Stifab Farex Ab | Silencer with baffles for rectangular ventilation ducts |
DE10243710B3 (en) * | 2002-09-20 | 2004-03-11 | Lta Lufttechnische Komponenten Zweigniederlassung Der Berlinerluft. Technik Gmbh | Sound-damping device for air ducting has sound-damping cushion fitted with sheet metal flow profiles at end facing air flow for reducing pressure loss |
DE102005002621B3 (en) * | 2005-01-20 | 2006-06-14 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Hermatically sealed sound insulation module has pair or pairs of interconnected curved metal plates forming hollow spaces to provide sound absorbency |
DE102009024728A1 (en) * | 2009-06-12 | 2010-12-16 | Bayerische Motoren Werke Aktiengesellschaft | Air guiding component comprises tubular resonator, particularly charge air hose for internal combustion engine with turbocharger, where resonator is introduced in air guiding component |
HUE038879T2 (en) * | 2011-09-30 | 2018-12-28 | Trox Gmbh Geb | Ventilation component |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1201528B (en) * | 1959-06-25 | 1965-09-23 | Bahco Ab | Silencer for ventilation units |
US3435911A (en) * | 1966-11-14 | 1969-04-01 | Greenheck Fan & Ventilator Cor | Acoustic curb |
DE2054053A1 (en) * | 1970-11-03 | 1972-05-04 | Grebig P |
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1975
- 1975-03-29 DE DE2513946A patent/DE2513946C2/en not_active Expired
-
1976
- 1976-02-19 AT AT117876A patent/AT349695B/en not_active IP Right Cessation
- 1976-02-23 SE SE7602087A patent/SE410217C/en unknown
- 1976-03-03 NL NL7602185A patent/NL7602185A/en not_active Application Discontinuation
- 1976-03-11 GB GB9725/76A patent/GB1512164A/en not_active Expired
- 1976-03-15 NO NO760896A patent/NO145736C/en unknown
- 1976-03-15 DK DK110576A patent/DK147533C/en not_active IP Right Cessation
- 1976-03-16 ZA ZA761614A patent/ZA761614B/en unknown
- 1976-03-22 AU AU12233/76A patent/AU505475B2/en not_active Expired
- 1976-03-24 IT IT04816/76A patent/IT1202986B/en active
- 1976-03-26 FR FR7609561A patent/FR2306395A1/en active Granted
- 1976-03-26 BR BR7601837A patent/BR7601837A/en unknown
- 1976-03-26 CH CH378776A patent/CH601745A5/xx not_active IP Right Cessation
- 1976-03-27 ES ES446442A patent/ES446442A1/en not_active Expired
- 1976-03-29 BE BE2054910A patent/BE840133A/en unknown
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DK157044B (en) * | 1978-10-13 | 1989-10-30 | Leif Ingemar Lind | STUDY DISTRIBUTION BODY INCLUDED IN AN AIR SUPPLY BODY |
Also Published As
Publication number | Publication date |
---|---|
CH601745A5 (en) | 1978-07-14 |
DE2513946C2 (en) | 1981-11-26 |
FR2306395A1 (en) | 1976-10-29 |
GB1512164A (en) | 1978-05-24 |
NO145736B (en) | 1982-02-08 |
ZA761614B (en) | 1977-03-30 |
BE840133A (en) | 1976-07-16 |
DK147533C (en) | 1985-08-12 |
SE410217C (en) | 1980-12-04 |
NO145736C (en) | 1982-05-19 |
SE410217B (en) | 1979-10-01 |
AT349695B (en) | 1979-04-25 |
NO760896L (en) | 1976-09-30 |
IT1202986B (en) | 1989-02-15 |
NL7602185A (en) | 1976-10-01 |
AU1223376A (en) | 1977-09-29 |
ES446442A1 (en) | 1977-06-16 |
DE2513946A1 (en) | 1976-10-14 |
ATA117876A (en) | 1978-09-15 |
BR7601837A (en) | 1976-10-05 |
DK110576A (en) | 1976-09-30 |
AU505475B2 (en) | 1979-11-22 |
FR2306395B3 (en) | 1978-12-22 |
SE7602087L (en) | 1976-09-30 |
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