FR2824387A1 - Autonomous suspension system for producing ultra clean beam of horizontal laminar air flow comprises filters mounted in casings suspended by tubes through which air from treatment unit is filtered - Google Patents

Abstract

The system enables an ultra clean beam of air with a horizontal laminar flow (1) to be obtained by means of a filter (2) mounted in a sealed casing (3), the air coming from an upstream air treatment unit (12). The air beam is caught by another filter (20) in a sealed casing (21) located in the axis of the first casing. The casings are suspended by tubes (7,23) through which they communicate for the air circulation.

Description

each element.

  The present invention relates to an autonomous suspension device allowing

  to create an ultra clean air beam with horizontal laminar flow.

  Many sectors of activity such as microelectronics, pharmaceutical laboratories, the food industry, aerospace, hospitals ... are faced with the risks of contamination or blockontamination. Contamination is the consequence of the presence of an undesirable element in a material or on a surface; it leads to a qualitative disturbance in an industrial production operation and significant economic consequences. Biocontamination is the consequence of the introduction of microorganisms in the manufacture or packaging of food products or in the open wound of the patient during a surgical operation, it constitutes a significant risk for the health of people. In hospitals, nosocomial infections represent a danger for the sick and a significant cost for society. Among the contamination or biocontamination factors, air is a significant vector. To guard against the risks of particulate or biological contamination by air, more and more industrial production operations have been developed in zones or enclosures with controlled contamination. These operations also imply controlling the temperature and the humidity of the air. These enclosures are designated as clean rooms or clean rooms; they are characterized or classified by their level of cleanliness according to national or international standards and according to the numerical concentrations of particles suspended in the air in a defined volume. The cleanliness of the air in a clean room or a clean room is achieved by means of an air treatment process. This process makes it possible to filter the air according to the required level of cleanliness, to ensure the temperature and the humidity of the air as well as the overpressure of the room. This process is carried out using a common air treatment device comprising at least one fan, a cooling battery, a heating battery and a filtration of fine particles. The air is generally diffused by false ceiling comprising a filtration of very fine particles. The air is taken up either by a perforated false floor or by

  openings at the bottom of the walls.

  The economic stakes and the evolution of technologies lead to increasing protection against the risks of contamination or biocontamination in industrial production processes or in zones with infectious risks. These technologies require a level of air cleanliness that clean rooms or current clean rooms cannot reach: in fact, the level of cleanliness of the room being obtained by dilution of the dust particles in a volume of air suitable for laminar diffusion, it would take more and more clean air to remove more and more dust particles. But the volume of clean air diffused in a room under laminar flow is limited to a diffusion speed of 0.45m / s maximum to preserve

  the laminarity of the flow. A higher speed would produce air turbulence.

  The impossibility of increasing the volume of clean air without increasing the air speed and therefore of causing turbulence harmful to the desired objectives limits the increase.

  cleanliness of rooms according to current processes.

  The realization of ultra clean fillings, the design of more efficient processes to reduce the risks of contamination or blockontamination, go through actions close to the production tools, packaging or wounds of the patients. Rather than treating large areas, it is a question of treating only the areas sensitive to risks and thus constituting mini

ultra clean environments.

  The process of ultra clean air by mini environment can be with open or closed system. In the context of the present invention, it is a mini

open environment.

  It is common to find on the market, closed systems such as autonomous stations for diffusing clean air integrated into a work table. These stations are most often used in laboratories for small analytical work which does not require ultra clean air. There are also on the market, autonomous clean air distribution stations with vertical flow mounted on feet; but these devices are not suitable for industrial production due to their designs

  and their performance is too limited.

  The device according to the invention makes it possible to produce an air beam with horizontal laminar flow in order to constitute an open mini ultra clean environment, autonomous, without any material or accessory on the ground. This device is adaptable to all production, intervention, conditioning, or control situations and whose physical characteristics of the air, in terms of cleanliness, temperature or humidity, can be controlled. It allows one or more people to operate in an air flow

  ultra clean without any material obstacle and at the temperature and humidity of the desired air.

  The ultra-clean air beam is produced from a short circuit and an autonomous air treatment system operating in recycling; it is generally horizontal and located at a useful distance from the ground depending on its use; it is not in contact with any architectural element. This device increases working performance by

  ultra clean environment and reduce production costs.

  The ultra clean air beam with horizontal laminar flow is produced from a loop circuit, open to the field of application. The air is taken in from the room, under the action of an air treatment unit, by a filtering box suspended from a tube which serves as an air duct, and connected to the suction of the unit. air treatment. After treatment, the air is sent by a device similar to a diffusion box containing a filtration system. The air beam is produced by the very fine particle filter made up of multiple grooves allowing the diffusion of a laminar flow at a speed established as a function of the distance which separates the air diffusion plane from the air suction plane. located in the same axis. The dimensions of the filters located at the air diffusion and suction are identical. The air diffusion and suction speeds are similar. The air beam section is little different from that of the filters

  located at the air diffusion and suction.

  According to a particular form, the device according to the invention can be produced in the following way: In the direction of the air and from its suction, the circuit can comprise: - An air suction box with a filter interchangeable to eliminate

  fine particles of dust and protect the cleanliness of the circuit.

  - A rigid column that can be fixed to the ceiling, supporting the suction box

  air and forming a conduit for the circulation of the aspirated air.

  - A duct connecting the column of aspirated air to the air treatment unit.

  - An air treatment unit including in particular the equipment allowing

  provide circulation, ie cooling, and humidification of air.

  - An air diffusion box with interchangeable filter to eliminate very

  fine particles of dust and produce an ultra clean air beam.

  - A rigid column that can be fixed to the ceiling, supporting the diffusion box

  air and forming a conduit for the circulation of the blown air.

  - A duct connecting the supply air column to the air treatment unit.

  The accompanying drawings illustrate the invention:

  Figure 1 shows the device of the invention in section along a vertical plane.

  Figure 2 shows the device of the invention seen from above in horizontal section.

  FIG. 3 represents a partial view of the device of the invention on the surface of

beam air outlet.

  FIG. 4 represents a partial view of the device of the invention on the surface of

air return from the beam.

  FIG. 5 represents the device of the invention seen from above.

- 4

  FIG. 6 represents a variant of this device according to FIG. 3.

  FIG. 7 represents another variant of this device of the invention.

  FIG. 8 represents another variant of this device of the invention.

  FIG. 9 represents an alternative installation of the device of the invention.

  FIG. 10 represents the top view of the device according to FIG. 9. With reference to these drawings and according to FIGS. 1 2 - 3 - 4 and 5, the device comprises a filter (2) whose function is to filter the very fine dust particles and ensure the laminarity of the air when blowing. This filter (2) is mounted in an airtight enclosure (3). A watertight hatch (4) located on the rear of the box (3) allows the filter (2) to be assembled and disassembled. A seal (5) compressible by devices (6) seals between the filter (2) and the box (3). The volume of the box (3) communicates with a tube (7) located on its upper face and mounted vertically with the function of keeping it in suspension from a ceiling (27) and ensuring the circulation of air through orifice (8). The tube (7) on its end opposite the box (3), is closed, and has a part (9) for fixing it to the ceiling and an intermediate lateral opening (10) for the connection of another conduit (11) having the function of prolonging the circulation of air between the tube (7)

  and the air handling unit (12).

  The air treatment unit (12) groups the following equipment in a box (13): an acoustic correction device (14), an exchanger (15) supplied with cold water, a motor fan (16), a device acoustic correction (17), a

  humidification ramp (18). The box (13) is isolated from the outside box (19).

  A filter (20) whose function is to filter fine particles of dust and preserve the cleanliness of the air circuit. This filter (20) of the same dimensions as the filter (2), is mounted in an airtight box (21). A sealed hatch (22) located on the rear of the box (21) allows the filter (20) to be installed and removed. A seal (5) compressible by devices (6) seals between the filter (20) and the box (21). The volume of the box (21) communicates with a tube (23) located on its upper face and mounted vertically with the function of keeping it in suspension

  from a ceiling and ensuring the circulation of air through the orifice (24).

  The tobe (23) on its end opposite the box (21) is closed and has a part (9) for fixing it to the ceiling (27) and an intermediate lateral opening (25) for the connection of a another duct (26) having the function of prolonging the circulation of air between the tube (23) and the air treatment unit (12). The box (21) is located in the axis of the box (3). The air leaving the box (3) at a certain speed and

  taken up by the box (21) at the same speed, constitutes the clean uitra air beam (1).

  According to a variant illustrated in 6, the boxes (3) and (21) can be connected to 1 or more tubes in (7) or (23) According to a variant illustrated in 7, the box (3) can receive one or more

  lamps (28) having an anti bacterial action.

  According to a design illustrated in 8, the tubes (7) or (23) can be equipped with plates (29) adjustable in height or in orientation to serve as support for devices. According to a variant illustrated in 9 and 10, the air treatment unit (12) can be located above a ceiling. The rods (7) and (23) then cross the ceiling

  for an identical connection to the initial device illustrated in 1.

  The device according to the invention is particularly intended for production operations in an ultra clean environment in a mini environment and in particular for the production of memories in the electronics sector, for the production of computer media, for the manufacture of space material, for production

  precision watchmaking, for the production of micromechanics ...

  The device according to the invention is also intended for the production and

  packaging of food products, production of sterile products ...

  The device according to the invention is particularly well suited to operating rooms in the context of the protection of the operating field in interventions

surgical ...

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Claims (5)

  1) Autonomous suspension device making it possible to produce an ultra-clean air beam with horizontal laminar flow (1) by means of a filter (2) mounted in a sealed box (3) and from a treatment unit d air (12) placed upstream of the box (3). This air beam (1) is taken up by another filter (20) of the same dimensions as the filter (2), mounted in a sealed box (21) and located in the axis of the box (3). 2) Device according to claim 1 characterized in that the filter boxes   (3) and (21) are suspended from tubes (7) and (23).   3) Device according to claims 1 and 2 characterized in that the box (3)   and (21) communicate respectively with the tubes (7) and (23) for the circulation of 1 0 air.   4) Device according to claims 1, 2 and 3 characterized in that the tubes   (7) and (23) serve as ceiling installation supports for the boxes (3) and (21)   ) Device according to claims 1, 2, 3 and 4 characterized in that the tubes   (7) and (23) communicate with an air treatment unit (12).   6) Device according to claims 1, 2, 3, 4 and 5 characterized in that the   boxes (3) and (21) respectively containing a filter (2) and a filter (20) constitute   the ends of the same circuit.   7) Device according to all of the claims characterized in that the   fiitres (2) and (20) consist of parallel fine channels creating an air beam at