EP2942575A1 - Laminar flow passage device - Google Patents

Abstract

The laminarizer passage device has a laminarizer (8) and at least one media panel (17). The media panel (17) is inserted into the laminarizer (8) in the form of a passage member (laminarizer passage member) and has a round at its downstream end (18), forming a flow at a small distance downstream of the media panel (17) which is low-turbulence or laminar up to a working plane (15).

Description

The invention relates to a laminarizer passage device according to the preamble of claim 1.

Such a device is from the DE 100 58 721 C2 known.
There, an operation lamp is shown on a Deckenarmsystem having a light source in a lamp housing and a gas conveyor with a running through the Deckenarmsystem flow channel, which opens into the lamp housing, wherein an air outlet is arranged on the underside of the lamp housing.

The WO 2012/013749 A2 describes an operating light, which is completed by a hemispherical transparent cover in the light exit direction and in a room ceiling has an air flow generating device which flows around the lamp and should produce a laminar as possible flow.

A similar operating light to a ceiling arm system is in the US 2009/0288555 A1 described in which the light exit opening of the Operating light is also closed by a hemispherical transparent cover and should also cause a laminar as possible air flow.

The WO 2013/064490 A1 shows a surgical lamp with a lamp housing, which is surrounded by air and in the flow direction behind the lamp housing on the outside has a plurality of trough-like depressions.

The US 5443625 A shows an air filter device for a room which is mounted in the ceiling of the room, having one or more fans and a filter network. A filter housing is designed so that room air is sucked in and transported away through the filter to the outside.

In clean room technology, such as in operating theaters with high requirements for germ reduction, on the one hand care must be taken to ensure that low-turbulence air flows are present in the working area (protection area) and on the other hand this area is well lit and working tools can be introduced into the working area such that a low-turbulence air flow is not or is disturbed as little as possible.

To produce a low-turbulence flow usually laminarizers are used, for example, from the EP 2522924 A2 or the DE 10 2008 019698 B3 are known. The lighting is usually realized by ceiling lamps, which are arranged laterally next to the laminarizers and by surgical lights, which are suspended by a gimbal and can be positioned and swiveled according to the lighting requirement. Work equipment such as suction devices, flushing devices, RF power supply, etc. are now usually supplied to the side of the work area, which disturbs the work area, makes it confusing and also disturbs the desired low-turbulence air flow. In some cases, these tools are also supplied with a Kardanik.

Lighting alone through ceiling lamps is in practice insufficient in terms of light intensity in the work area. Operating theater lights with gimbals have the disadvantage that the laminar air flow is disturbed and turbulences occur. These turbulences can cause or promote the transport of particles as well as microorganisms from the operator (face, clothing, etc.) into the protected area as well as from the working area into the respiratory area of the surgeon.

The laminar (LAF) or low-turbulence displacement flow (TAV) is well known from clean room technology and has found its way into the generally accepted rules of technology ( DIN 1946 Part 4, Ventilation Systems in Hospitals, (2008) Beuth Verlag ; DIN EN 13779, Ventilation of non-residential buildings, (2007) Beuth Verlag GmbH ; DIN EN 13182, Ventilation for Buildings, Equipment Requirements for Air Velocity Measurements in Ventilated Rooms (December 2002) Beuth Verlag ; VDI 2083 clean room technology, sheet 2 (2005 ) Measurement technology in the clean room air and sheet 5 (1996), thermal comfort, building, enterprise and maintenance, Beuth publishing house ).

• < 5 % à laminar (LAF),
• 5-20 % à turbulenzarm (TAV),
• > 20 % à turbulent.

The degree of turbulence is defined as a measure of the fluctuations in relation to the mean value of the air velocity in accordance with DIN EN 13182 or VDI 2083. It is approximately equal to the relative standard deviation (standard deviation by mean) when the number of samples is large and the direction of the speed-time fluctuations is ignored. There are three parameters for the degree of turbulence (VDI 2083 Part 5, Table 1): flow with a degree of turbulence of

• <5% à laminar (LAF),
• 5-20% à turbulence arm (TAV),
• > 20% à turbulent.

LAF or TAV systems are used wherever aerogenically transmitted particulate or gaseous contaminations of products and work surfaces, such as e.g. in industrial operating rooms, must be kept away from the product (product protection) or the working personnel (personnel protection).

To produce a protected area by means of LAF or TAV flow, supply air is firstly generated by fans, optionally sterile filtered by means of HEPA filters (High Efficiency Particulate Air Filter) and, after flowing through "laminarizers", specifically into entire rooms or a limited protection or Work area introduced. Laminarizers are known in the art, have been optimized in many variants in recent decades ( EP 0355 517 B1 ) and achieve a reduction in the degree of turbulence, so that exchanged from the overflowed surfaces less energy with the flowing air or fewer particles are removed or dumped.

After low-turbulence or overflow of the protected area, the air is discharged via exhaust openings in the floor, on walls or ceiling-fixed suction systems.

Typical applications for this technology are, for example, microelectronics for the production of computer chips, the optical industry, production and filling areas in the pharmaceutical industry, food technology and the operating rooms in medicine.

Especially operating rooms are to fulfill their task as "clean rooms" according to DIN 1946 Part 4, as a generally accepted rule of technology, in those of the class 1a (low-turbulence displacement flow) with the highest air quality cleanliness and the space class 1b (turbulent air flow) with lower air quality cleanliness distinguished. The room class 1a usually has the installation of several (HEPA) supply air filters under the operating room ceiling. Using these filters and the subsequent laminarizer, the supply air, which is colder than the air in the room, is guided to the protection and working area vertically below the operating area and instrument tables. Usually and in accordance with DIN 1946 Part 4, the supply air ceiling outlet is located in the middle area of the operating room and occupies an area of 3.2 x 3.2 square meters. This allows a ventilation-related defined protection area of 3 x 3 square meters to be displayed in the operating room.

In order to let the supply air from the ceiling outlet be physiologically comfortable for the OR team, "laminarisers" (also tissue distributors, CG distributors [CibaGeygi: first-time application]) are stretched under the HEPA inlet air filter as fine-meshed (plastic) tissue. These laminarizers produce a flow with low degrees of turbulence and thus a desired, rectified, low-turbulence or laminar air flow. In a suitable combination of thread size and mesh size, laminar flows (degree of turbulence: <5%) can be detected up to the working level of the operating table (1-1.2 m OKFFB [upper edge of finished floor]).

Flow obstacles located downstream below the level of the laminariser usually increase the degree of turbulence or have a negative effect on the quality of the air flow in the working area to be protected. Thus, for example, surgical lights whose tripod tubes must be routed through the plane of the laminarizers, it is known that both the tripod bushing and the lamp increase the degree of turbulence locally. Further examples of such flow disturbances in the operating room in the area between laminarizer and protective area are ceiling supply units (medical Gases, electricity) and screens for process monitoring.

In principle, clean rooms are characterized by special lighting systems in addition to these air duct systems as well as task-specific (processing) equipment. So z. B. installed in clean rooms for medical operations and invasive procedures on humans and animals specially combined lighting systems. According to DIN EN 12464-1, a distinction is made between the "visual task area" with the highest requirements for the luminance of the immediate "surrounding area" (about 0.5 m around the visual field of the visual task) and the "background" (about 3 m around the visual task).

For the "field of visual task" surgical lights are used, which reach luminance densities of 10 or 40-160 kLx (DIN EN 12464-1, DIN EN 60601-2-4) at a distance of 1 m, so that even in patients with significant Body mass even the filigree tissue and organ structures lying deep in the body can be distinguished, recognized and treated as error-free as possible. In order to minimize disabling shadows, for example by the surgeons' heads, in the area of the visual field of the surgical field, usually at least two surgical lights installed redundantly to ensure adequate lighting.

According to DIN 5035-3, the "ambient area" must be supplied with luminance values of 1, 5-2 kLx and the "background area" with 1.0 kLx (DIN EN 12464-1). Typically, the illumination of the "surrounding area" by means of one or more juxtaposed rows of Neo-room lights (2-3 rows), which are installed circumferentially around the Zuluft-Deckenauslass on the operating room ceiling. On the one hand, these enable the surgical team to have a sufficient overview of the instruments and devices used (eg for instrumentation and anesthesia). On the other hand, the illumination in the "ambient" and "background" areas prevents the surgical team from being subjected to adaptation disorders due to excessively high luminance differences from the visual task area. This ensures physiologically acceptable contrasts and fulfills the protection requirement according to the valid accident prevention regulations (GUV-I-8681).

As a predominantly common installation, multi-row neon lights are mounted on the side of the ventilation ceiling outlet on the operating room ceiling. The disadvantage of this lateral arrangement is that these lights in the direction of OP floor are directed and the protection area, which is to be illuminated with a luminance of 1-2 kLx, due to the diagonal is a large distance.

However, lighting systems are also known in the art, with neon ceiling lights mounted between the (HEPA) supply air filters and the laminarizer installed below. The advantage here is that the emitted light radiates directly from above and thus on a shorter path to the underlying protection area. A disadvantage of this type of installation, however, is that the light intensity is considerably reduced by the laminarizer. Another disadvantage is the increased technical effort to change the bulbs, since this laminarizer must be completely disassembled.

In the course of an operation, which lasts an average of one hour (about 10 minutes to> 15 hours), there are constantly changes in the local situation or the depth of the surgical field edited by the surgical team. To adjust the required illumination according to these process-related changes in position of the visual task, the operating lights must be repositioned by means of the gimbals. These changes are usually made manually by the Surgery team itself or by helpers ("Springer"), who have to run to fulfill this task especially in the operating room. Due to the stiff gimbals, the correct setup of the surgical lights is physically demanding and the necessary sterile conditions are also difficult.

Object of the present invention is therefore to provide a device with the tools can be introduced in turbulence-poor flow in a workspace.

This object is achieved by the features specified in claim 1. Advantageous embodiments and further developments of the invention can be found in the dependent claims.

The basic idea of the invention is to integrate a media panel into the laminarizer so as to provide a low-turbulence flow after a short downstream distance to the media panel. The media panel is used as a passage element in an opening of the laminarizer, such that it passes through the laminarizer, wherein its downstream end is rounded so that there forms a low-turbulence flow. The rounding is preferably hemispherical or in the form of a paraboloid of revolution. The media panel preferably has connections for electric current and / or suction devices and / or fluid supply devices.

According to a development of the invention, a connection for a glass fiber light cable is additionally provided on the media panel, wherein a light source or a fiber optic light cable to be supplied is arranged in the interior of the media panel. As a light source for the optical fiber light cable LED's are preferably proposed.

Preferably, the media panel is height adjustable and in particular by a telescopic guide.

For this purpose, examinations were carried out in an operating room with a TAV-Zuluftdeckenauslass of 3.2 x 3.2 square meters (according to space class 1a / DIN 1946 Part 4) with a installed at 2.7 m height OKFFB laminarizer. Turbulence level probes were installed in 81 measurement positions vertically below the laminarizer (1 m height OKFFB). The 9 x 9 measuring positions had a distance of 5 cm from each other. For supply air velocities of 0.23 m / s, 0.27 m / s and 0.30 m / s, a mean degree of turbulence of <5% (laminar flow) was found.

Subsequently, successive metal disks of 80, 120, 160 and 230 mm diameter (0.4 mm thickness) were fixed on the downstream side of the laminarizer. Then, in the respective constellation, the determination of the degrees of turbulence in comparison to the initial conditions (without metal disc). As a result, at all supply air velocities, the metal disks up to 120 mm diameter on the working plane did not cause any exceedances of the degree of turbulence of 5%. With the metal disc diameter of 160 mm, the turbulence level of 5% was exceeded at all supply air speeds.

This was followed by visualization studies in that aerosol mist was injected via plastic probes in the flow direction below the metal tubes. The turbulent flow below the metal disks was photographed and measured as a function of the flow velocity. As a result, it was found that the turbulent flow below the metal plate basically took a semi-conical shape whose length never exceeded 1.2 times the diameter of the metal plate.

With the same experimental setup as for round metal discs, further investigations were carried out with different shapes. there In summary, it could be determined that round and oval as well as (four- and six-) square shapes did not exceed the turbulence level of 5%, if they had a diameter <160 mm.

In particular, however, it turned out that the degree of turbulence in the working plane at the diameter of 160 mm could be considerably reduced by using metal tubes instead of the metal plates, which (like the metal plates) were fixedly closed on the laminarizer and had a rounding downstream , preferably in the form of a paraboloid of revolution or a hemisphere.

The invention is therefore based primarily on the recognition that a passage element (LPE for laminarizer passage element) introduced into the laminarizer "initially generates locally below a hemispherical turbulent flow, however, due to appropriate selection of shape and diameter of the passage element (LPE) The turbulence-poor air flowing sideways is returned to a turbulence-free flow form after the maximum diameter of the LPE, thus restoring the work plane in the protected area to turbulence-poor flow.

Based on this finding, a media panel was developed, which is passed through the laminarizer in the form of a passage element and at the lower end has a flow favoring round shape, which is preferably hemispherical or formed as a paraboloid of revolution. As a result, fiber optic cable connections (adapters) can be guided very close to the work plane. This makes it possible, the required for the field of visual task, very high luminance, z. B. via fiber optic cable in gooseneck technology, lead directly to the work area.

Furthermore, via specific adapters in the media panels both the supply of high-frequency current (high-frequency surgery, diathermy) and the suction of the thereby released "Surgical Smoke", take place directly at the working level, without suction tubes above the floor area (risk of tripping!) Must be laid ,

Fig. 1

einen Reinraum mit einem "Medienpanel";

Fig. 2

eine Ansicht ähnlich Fig. 1 mit an das Medienpanel angeschlossenem Lichtleitkabel; und

Fig. 3

eine schematische Draufsicht auf die Vorrichtung nach der Erfindung.

In the following the invention will be explained in more detail by means of exemplary embodiments in conjunction with the drawing. It shows:

Fig. 1

a clean room with a "media panel";

Fig. 2

a view similar Fig. 1 with fiber optic cable connected to the media panel; and

Fig. 3

a schematic plan view of the device according to the invention.

Fig. 1 shows a clean room 1 with a bottom 2, a ceiling 3 and side walls 4. On the ceiling 3, an air supply device 5 is attached, which has a fan 6, an air filter 7 and a laminarizer 8. The laminarizer 8 has a plurality of openings in which lighting devices 10 are inserted. The lighting devices 10 have a closed housing 9, are arranged in the light source and on the facing towards the interior of the clean room 1 side a translucent disc 11 which may be flat, but also curved convex or concave to focus the light or to scatter. The housings 9 partly protrude beyond the underside of the laminarizer 8 into the clean room and have a sharp tear-off edge 12. The housings 9 thus have the shape of a tube which is closed at the end. The tubular opening of the housing 9 preferably protrudes at least 1 mm, preferably 2 mm, out of the plane of the laminarizer 8. The cross-sectional shape of the housing is largely arbitrary and can, for example, square, be circular, elliptical or n-sided with n> 3.

The air flows conveyed by the fan 6 pass through the laminarizer 8 and flow around the housings 9. Turbulence normally forms in the flow direction below the housings 9. Due to a tear-off edge 12 on the housings 9, the region of turbulence has an approximately hemispherical shape with a length which corresponds approximately to the width 14 of the housing 9 and is not greater than about 1.2 times the largest diameter of the housing. After this range, the flow is again, according to the requirements of the respective clean room quality, laminar or low turbulence.

With a sufficient distance between the protruding into the space 1 housing 9 and a working plane 15 is thus ensured that laminar or low-turbulence flow arrives at the working level 15. At the same time, illumination of the working plane 15 with substantially increased luminances can be achieved by the light sources 10, whose illuminants are preferably glass fibers or LEDs.

Another advantage of the invention is in Fig. 1 shown. By dispensing with the classic surgical lights with gimbals, the level of laminarizer 8 can be up from the current 2.7-3 m Be lowered ≤ 2.5 m. As a result of this reduction between the laminarizer plane and working plane 15, the luminance is substantially increased there, since the luminance is known to decrease with the square of the distance between the light source and the irradiated object.

Next eliminates the aforementioned handling with the gimbals of surgical lights, since the individual light sources are arranged remotely pivotable in the LPE, so that the light of several sources concentrated on a narrower work area and so the local focus can be changed.

After the in Fig. 1 1 or more housings 9 may be replaced by one or more media panels 17. The media panels 17 are passed through the laminarizer 8 as a passage element and have at its directed to the working plane 15 downstream end 18 a flow favorable round and in particular hemispherical or rotationsparaboloidische shape, so that forms a low-turbulence flow in the further flow. The media panels may have various ports 19, 20, such as. As for the supply of HF power and the suction of gases and liquid mist ("Surgical Smoke") or the supply of fluids, such as gases or liquids, what can be done very close to the working level 15. This also reduces the number of hoses and cables running next to the work surface (eg operating table).

As in Fig. 2 2, a connection 19 for a light-conducting cable 21 can be provided on the media panel 17 with which the special lighting required for the visual task can be brought into any proximity to the working plane 15, for example via a so-called "gooseneck". Thus, under difficult operating conditions, a very bright illumination can be brought directly to the point to be illuminated (visual task).

Fig. 3 shows a plan view of the laminarizer 8 with several housings inserted 9 and illustrates that the housing 9 can have very different shapes, such. B. square, circular, elliptical, hexagonal, etc.

In a concrete embodiment with a laminarizer 8 of a total area of 3.2 mx 3.2 m at a height of 2.7 m, the diameter of the housing was 12 cm. The distance b between two adjacent housings 9 was 5 cm and the distance c of the housing 9 to the edge of the laminarizer 8 was 10 cm. With these dimensions was below the housing 9 after a distance which is at most 1.2 times the diameter a of the housing 9, a visualization of the flow is documented and a degree of turbulence of <5% is always measured in the working plane.

In Fig. 2 It can also be seen that additional luminaires 22, which provide sufficient background illumination of the clean room 1, can be arranged on the ceiling 3 laterally next to the work surface 15. Here also conventional neon lamps can be used. The height of the laminarizer 8 above the bottom 2 was 2.7 m. The height of the (height-adjustable operating table) working level 15 is usually between 80 cm and 1.40 m.

The dimensions given above have proven to be favorable in the specific embodiment. It is clear to the person skilled in the art that other dimensions can be used as long as it is ensured that a low-turbulence or laminar flow is present at a sufficient distance above the working surface 15.

Claims (5)

A laminarizer passage apparatus comprising an air flow generator, a laminarizer (8) and at least one media panel (17), the media panel (17) being disposed in an aperture of the laminarizer (8) in the form of a passage member such that it passes through the laminariser (8). passes
characterized,
that the service panel (17) at its downstream end (18) aufweiset such a rounding that downstream of the end (18) a low-turbulence flow occurs,
in that a connection (19) for a glass fiber light cable (21) is provided on the media panel (17) downstream of the laminarizer (8), wherein inside the media panel (17) a light source (10) or a feeding optical fiber light cable is arranged , and
that the service panel (17) downstream of the Laminarisators (8) has at least one further port (20) for electric current and / or suction and / or fluid supply means. Laminarizer passage device according to claim 1, characterized in that
that the rounding at the downstream end (18) is hemispherical or rotationsparabolisch. Laminarizer passage device according to one of claims 1 or 2, characterized
that the light source (10) comprises at least one fiber-optic light cable or a LED. Laminarizer passage device according to one of claims 1 to 3, characterized
in that it additionally comprises at least one light source (10) in the form of a passage element designed as a housing (9), the housing (9) having a downstream flow separation edge (12) formed by the additional housing (9) being a thin-walled tube is whose downstream stall edge (12) protrudes at least 1 mm above the plane of the laminarizer (8) and whose wall thickness is ≤ 3 mm and preferably ≤ 1.5 mm. Laminarizer passage device according to claim 4, characterized in that
that the housing (9) in plan view is square, circular, elliptical or n-angular, with n> 3, is.

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