EP0088313B2 - Hotte d'aspiration - Google Patents
Hotte d'aspiration Download PDFInfo
- Publication number
- EP0088313B2 EP0088313B2 EP83101890A EP83101890A EP0088313B2 EP 0088313 B2 EP0088313 B2 EP 0088313B2 EP 83101890 A EP83101890 A EP 83101890A EP 83101890 A EP83101890 A EP 83101890A EP 0088313 B2 EP0088313 B2 EP 0088313B2
- Authority
- EP
- European Patent Office
- Prior art keywords
- nozzle
- air
- hood
- opening
- section
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B15/00—Preventing escape of dirt or fumes from the area where they are produced; Collecting or removing dirt or fumes from that area
- B08B15/02—Preventing escape of dirt or fumes from the area where they are produced; Collecting or removing dirt or fumes from that area using chambers or hoods covering the area
- B08B15/023—Fume cabinets or cupboards, e.g. for laboratories
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B2215/00—Preventing escape of dirt or fumes from the area where they are produced; Collecting or removing dirt or fumes from that area
- B08B2215/003—Preventing escape of dirt or fumes from the area where they are produced; Collecting or removing dirt or fumes from that area with the assistance of blowing nozzles
Definitions
- the invention relates to a deduction according to the preamble of claim 1.
- a smoothly flowing, vertical air curtain is created in the area of the front intake opening between the nozzle bar for the supply air and the suction gap, with at least partially fresh air being introduced from the outside through the nozzle gap along the lower side, towards the suction nozzle gap at the top.
- FIGS. 3a and 3b of this prior publication in the case of a galvanic bath, supply air for transporting the resulting gases over the surface of the galvanic bath is blown into a collecting and guiding hood 20, in which case the hot exhaust gases P1 are swirled by a corresponding design of the hood 20 passed from which is sucked through the opposing suction openings 24.
- the relevant sash is missing from the housing.
- FIGS. 5a and 5b This also applies to the device according to FIGS. 5a and 5b, which is provided for extracting contaminated or bad air from a room or a building. It has a hood attached to the ceiling of the room or building for collecting and directing the air into the exhaust device. In this case, the supply air is blown in parallel to the cylindrical wall of the housing of the guide device, as a result of which a circular path is forced on this air, and suction is then extracted from the center of this circular movement. In this device, it is essential that as much room air as possible is extracted through the device.
- a trigger emerges in which the lateral side walls are provided over their entire surface with a plurality of holes through which the supply air is blown into the hood such that the speed in the area of the suction opening is greatest and falling to the back wall.
- the aim here is to achieve a uniform air flow in order to achieve a static air pressure in the discharge chamber. A swirling does not take place because the single fume cupboard is arranged and designed accordingly. In this way, the vortex field aimed at according to the invention does not arise, from the center of which suction is extracted.
- fume cupboards were equipped with a direct supply air connection in the dock area, through which air can be drawn in by the exhaust air blower. These fume cupboards differ from conventional fume cupboards without a supply air device in that air is drawn in via the supply air connection when the sash is closed and the air supply is restricted due to the vacuum in the fume cupboard. When the sash is open, however, most of the air is taken from the laboratory.
- Laboratory fume cupboards are also known in which supply air is blown out in front of the windshield in such a way that it is sucked into the fume cupboard when the sash is partially or fully open.
- the required air flow rate of conventional fume cupboards is specified in DIN 12924 and VDI guideline 2051.
- DIN 12924 In order to prevent outbreaks of harmful gas when the sash is partially or fully open, DIN 12924 therefore requires an ambient air inlet speed of at least 0.7 m / s when the sash is 100 mm open required. This means that the volume flow extracted every hour in commercially available fume cupboards is at least 400 m 3 / h of air. This high air throughput is a considerable cost factor for the operator of the fume cupboard, since this air is taken from the laboratory room and must therefore be returned to the laboratory room by an appropriate air conditioning system.
- the invention is therefore based on the object of specifying a deduction which enables the supply air to be blown in with a substantially higher percentage (approx. 80%) than previously (approx. 40%) without outbreaks of pollutants occurring. This object is achieved by the measures contained in the characterizing part of claim 1.
- the invention is based on the knowledge that a pure displacement flow, which is generated by blowing in supply air at any point in the fume cupboard, leads to outbreaks of harmful gas when the sash is open, since the entry speed of the room air is reduced by the additionally blown air and thus, for example, when the sash is fully open with an opening area of 1 m 2 at 400 m 3 / h of extracted air and 80% supply air is only approx. 0.02 m / s, so that even the smallest disruptions caused by drafts or bystanders lead to the mixing of harmful gas.
- the air speed in the area of the sash must be increased in the manner of a laminar air curtain, this air curtain being influenced by the generation of vortex fields inside the fume cupboard so that it is completely absorbed by the fume cupboard becomes.
- the vortex field is generated in a partially open laboratory fume cupboard by attaching vertically arranged nozzle strips (1) on both sides, the blowout direction of which is directed to the vertical center line of the sash (see Fig. 1).
- the direction of rotation of each vortex is determined by the blow-out direction of the associated nozzle bar (1) (cf. FIG. 1 b).
- the generation of the vortices avoids a blunt collision of the two air curtains appearing on the side, since they receive a velocity component directed into the fume cupboard due to the superimposed vortex field.
- the suction openings (2) can also be located in the base plate (5) of the fume cupboard, preferably if heavy gases are frequently used.
- the nozzle strips (1) have an approximately rectangular or square cross section (cf. FIG. 3) and are provided on their front side with an outlet opening (7, 7 ') which corresponds to the entire width of the strip (1).
- the outlet opening (7, 7 ') is closed by a flow resistance e.g. a metal cloth, spanned.
- a flow resistance e.g. a metal cloth, spanned.
- An improvement in the inflow conditions in the fume cupboard can be achieved in that a direction into the fume cupboard is impressed in the bottom region (5) of the fume cupboard of the boundary layer formed there. This is done by angling the lower part of the nozzle bar (1) such that the rectangular shape in the upper part changes into a trapezoidal shape (Fig. 3b). Since the air exits perpendicularly to the plane of the metal sheet stretched over the bar (FIG. 3a), this results in a different outflow direction between the upper and lower part of the nozzle bar (1). The outflow direction of the lower nozzle part must be directed into the interior of the fume cupboard.
- This division of the nozzle bar (1) requires a separate air supply for the upper one and lower nozzle part and is reached through a slot (11) between the rear wall of the nozzle and the inclined plate (9) located in the upper part of the nozzle
- An improvement in the speed distribution in the sense of an equalization over the entire front surface (7, 7 ') of the nozzle bar can be achieved by a rough surface of the plate (9) inclined in the nozzle bar (1) (e.g. felt covering, filter mats). This has an advantageous effect on the formation of the swirl fields.
- a stabilization of the vortex and an improved extraction of heavy gases in the bottom area (5) can be achieved by making a vertical slot (12) with a width of approx. 4 mm and a height of 100 mm in the middle of the rear exhaust wall, which is connected to the suction pipe is connected (cf. claim 8).
- the air supply for the nozzle strips (1) can be carried out separately for each nozzle body, but can also be carried out through a common line (13) which must have a branch for the left-hand and right-hand nozzle (1).
- the branching In order to obtain a uniform vortex distribution in the fume cupboard, the branching must be designed in such a way that the amount of air in the opposite nozzle strips can be adjusted when the fume cupboard is installed using a slide (or wedge).
Landscapes
- Ventilation (AREA)
- Prevention Of Fouling (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
- Detergent Compositions (AREA)
- Gas Separation By Absorption (AREA)
- Devices For Use In Laboratory Experiments (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
- Treating Waste Gases (AREA)
- Air-Flow Control Members (AREA)
- Filtering Of Dispersed Particles In Gases (AREA)
Claims (8)
caractérisée en ce que deux buses laminaires, mutuellement opposées dans un plan, sont prévues pour l'air amené ;
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT83101890T ATE16571T1 (de) | 1982-03-10 | 1983-02-25 | Abzug zur absaugung von gasen, daempfen und schwebstoffen. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE3208622 | 1982-03-10 | ||
DE3208622A DE3208622C1 (de) | 1982-03-10 | 1982-03-10 | Abzug zur Absaugung von Gasen,Daempfen und Schwebstoffen |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0088313A1 EP0088313A1 (fr) | 1983-09-14 |
EP0088313B1 EP0088313B1 (fr) | 1985-11-21 |
EP0088313B2 true EP0088313B2 (fr) | 1991-06-19 |
Family
ID=6157834
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP83101890A Expired - Lifetime EP0088313B2 (fr) | 1982-03-10 | 1983-02-25 | Hotte d'aspiration |
Country Status (7)
Country | Link |
---|---|
US (2) | US4550650A (fr) |
EP (1) | EP0088313B2 (fr) |
JP (1) | JPS58223444A (fr) |
AT (1) | ATE16571T1 (fr) |
DE (1) | DE3208622C1 (fr) |
DK (1) | DK116283A (fr) |
NO (1) | NO161897C (fr) |
Families Citing this family (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3232203C2 (de) * | 1982-08-30 | 1985-04-18 | Heinrich Dipl.-Ing. 5205 St Augustin Hilbers | Verfahren und Vorrichtung zum Absaugen und Abführen von Schadstoffen in Laboratorien oder dgl. |
DE3431669A1 (de) * | 1984-08-29 | 1986-03-13 | Müller, Johannes, 5202 Hennef | Laborabzug und absaugverfahren mit zulufteinleitung |
DE3604422A1 (de) * | 1986-02-13 | 1987-08-20 | Kessler & Luch Gmbh | Vorrichtung zum saeubern kontaminierter oberflaechen mittels stroemender luft |
JPH0248770Y2 (fr) * | 1986-05-29 | 1990-12-20 | ||
JPH0665935B2 (ja) * | 1987-07-10 | 1994-08-24 | 日本エアーカーテン株式会社 | 二連竜巻式空調換気機構 |
FR2619733B1 (fr) * | 1987-08-27 | 1991-11-22 | Rhone Poulenc Ind | Hotte de travail, notamment pour laboratoires |
JPH01137136A (ja) * | 1987-11-25 | 1989-05-30 | Nippon Air Curtain Kk | 人工竜巻式空調換気機構 |
JPH01300145A (ja) * | 1988-05-26 | 1989-12-04 | Japan Air Curtain Corp | 人工竜巻式の局所排気装置 |
DK312288D0 (da) * | 1988-06-08 | 1988-06-08 | Hansen & Raagaard Aps | Fremgangsmaade og anlaeg til mekanisk punktudsugning |
JPH02208435A (ja) * | 1989-02-07 | 1990-08-20 | Japan Air Curtain Corp | 人工竜巻発生機構及びその装置 |
KR920700530A (ko) * | 1989-03-29 | 1992-08-10 | 원본미기재 | 실험실 동물을 위한 공기조절장치 |
US5059079A (en) * | 1989-05-16 | 1991-10-22 | Proconics International, Inc. | Particle-free storage for articles |
JPH0331242U (fr) * | 1989-07-31 | 1991-03-27 | ||
DE9418235U1 (de) * | 1994-11-14 | 1995-01-05 | Mmm Medcenter Einrichtungen Gm | Vorrichtung, insbesondere Wärmeschrank |
US6089970A (en) * | 1997-11-24 | 2000-07-18 | The Regents Of The University Of California | Energy efficient laboratory fume hood |
DE19957962B4 (de) * | 1999-05-19 | 2009-01-29 | Röhl-Hager, Hannelore | Verfahren und Einrichtung zum Eingrenzen, Erfassen und Absaugen von fluiden Medien |
WO2000070230A1 (fr) * | 1999-05-19 | 2000-11-23 | Röhl-Hager, Hannelore | Procede et dispositif pour limiter, detecter et aspirer des milieux fluides |
WO2001044724A1 (fr) | 1999-12-14 | 2001-06-21 | Georg Emanuel Koppenwallner | Procede et dispositif pour separer et aspirer des fluides au moyen de generateurs de turbulences frontales |
US6302786B1 (en) | 2000-02-29 | 2001-10-16 | Case Systems, Inc. | Vented cabinet |
US6428408B1 (en) | 2000-05-18 | 2002-08-06 | The Regents Of The University Of California | Low flow fume hood |
GB2390151B (en) * | 2002-06-28 | 2006-05-10 | Tornex Inc | Enclosure-based suction apparatus |
ITPN20060058A1 (it) | 2006-07-27 | 2008-01-28 | Electrolux Professional Spa | Cappa di aspirazione a ventilazione perfezionata |
DE102009034342A1 (de) * | 2009-07-20 | 2011-03-03 | Fachhochschule Lausitz | Vorrichtung und Verfahren zur Absaugung |
TWI426220B (zh) * | 2011-03-22 | 2014-02-11 | Univ Nat Taiwan Science Tech | An exhaust device with a flap plate |
KR101934457B1 (ko) * | 2011-11-17 | 2019-01-04 | 삼성전자주식회사 | 환기 장치와 이를 포함한 환기 시스템 |
US9541296B2 (en) * | 2014-05-22 | 2017-01-10 | National Taiwan University Of Science And Technology | Soot-exhausting device |
DE202017002012U1 (de) * | 2016-05-17 | 2017-08-21 | Brand Gmbh + Co Kg | Gehäuse für ein Laborgerät |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3021776A (en) * | 1958-02-19 | 1962-02-20 | Barber Colman Co | Method and apparatus for ventilating laboratory fume hoods |
US3023688A (en) * | 1958-05-16 | 1962-03-06 | Jr Fred A Kramer | Air barrier |
GB1002297A (en) * | 1960-06-14 | 1965-08-25 | Henry George Frederick Jenning | Improvements in or relating to fume cupboards |
DE1289974B (de) * | 1964-11-07 | 1969-02-27 | Siemens Elektrogeraete Gmbh | Einrichtung zum Absaugen von mit unerwuenschten Beimengungen versetzter Luft |
US3254588A (en) * | 1965-05-24 | 1966-06-07 | Truhan Andrew | Laboratory fume hood |
US3408914A (en) * | 1967-02-06 | 1968-11-05 | Bayern Joseph | Fumehood with auxiliary air supply and by-pass conduit means |
CH445784A (de) * | 1967-03-11 | 1967-10-31 | Krantz H Fa | Kapelle für Chemielabors |
US3747505A (en) * | 1972-02-18 | 1973-07-24 | American Hospital Supply Corp | Air flow system for fume hood |
US4050368A (en) * | 1976-01-02 | 1977-09-27 | Marion L. Eakes Co. | Exhaust system for industrial processes |
US4339248A (en) * | 1976-11-08 | 1982-07-13 | Grow Group, Inc. | Process for the purification of gaseous effluent from industrial processes |
US4123967A (en) * | 1977-06-08 | 1978-11-07 | Shanis Arnold A | Air barrier device using pressurized swirls |
-
1982
- 1982-03-10 DE DE3208622A patent/DE3208622C1/de not_active Expired
-
1983
- 1983-02-25 EP EP83101890A patent/EP0088313B2/fr not_active Expired - Lifetime
- 1983-02-25 AT AT83101890T patent/ATE16571T1/de not_active IP Right Cessation
- 1983-03-03 US US06/471,817 patent/US4550650A/en not_active Expired - Fee Related
- 1983-03-09 NO NO830828A patent/NO161897C/no unknown
- 1983-03-10 JP JP58038388A patent/JPS58223444A/ja active Granted
- 1983-03-10 DK DK116283A patent/DK116283A/da not_active Application Discontinuation
-
1985
- 1985-03-18 US US06/712,769 patent/US4622888A/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
US4550650A (en) | 1985-11-05 |
DK116283A (da) | 1983-09-11 |
NO161897C (no) | 1989-10-11 |
EP0088313A1 (fr) | 1983-09-14 |
JPS58223444A (ja) | 1983-12-26 |
US4622888A (en) | 1986-11-18 |
JPH035852B2 (fr) | 1991-01-28 |
ATE16571T1 (de) | 1985-12-15 |
DE3208622C1 (de) | 1983-12-15 |
NO830828L (no) | 1983-09-12 |
DK116283D0 (da) | 1983-03-10 |
EP0088313B1 (fr) | 1985-11-21 |
NO161897B (no) | 1989-07-03 |
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