JP2011208872A - Clean room - Google Patents

Abstract

PROBLEM TO BE SOLVED: To overcome a problem that it is difficult to generate laminar flow in the entire room, in a clean room in which only downflow is generated, though it is necessary to generate substantially-laminar flow capable of quickly discharging air so that dust and an organic solvent are not diffused and accumulated regardless of existence of obstacles such as a manufacturing device in a manufacturing step of a liquid crystal module and PDP (plasma display panel).SOLUTION: A wind velocity of 0.1-0.15 m/sec is required for downflow air to achieve substantially-laminar flow regardless of the existence of obstacles. In this clean room 1, a fully-filtered chamber 25 is disposed on a place having a height of 1,800 mm under a ceiling, to achieve the downflow of the wind velocity, and further a straightening means 20 is disposed on a place below by 600-900 mm from the ceiling 8.

Description

  The present invention relates to a clean room that generates a laminar flow from above in order to obtain a predetermined cleanliness when manufacturing electronic components (particularly liquid crystal modules).

  The manufacture of liquid crystal modules and plasma display panels (hereinafter referred to as “PDP”) includes the steps of modularizing minute wirings and airtight bonding. It is necessary to work with. This is because in these steps, the presence of dust causes a product defect.

  Moreover, in order to cope with the manufacture of various products, the manufacturing process of these products includes not only a fully mechanized manufacturing line but also a work process performed by a person. For this reason, it is necessary to exhaust the volatile chemicals before they diffuse into the work environment, such as the solvent component of the adhesive used. This is because it is not preferable for the operator to fill the working environment with the solvent.

  For the above reasons, in the production of liquid crystal modules and PDPs, it is preferable to use a clean room in which laminar flow due to purified air is generated from the ceiling. However, since the manufacturing apparatus and the like are arranged in the work environment in the manufacturing process described above, the wind flow is turbulent and a turbulent flow is generated by the manufacturing apparatus or the like simply by generating the downflow. That is, even if there is an obstructed air flow in the manufacturing apparatus or the like, it is necessary to allow the air to flow in the grating disposed in the lower part of the clean room so that a substantially laminar flow can be formed.

On the other hand, some technologies relating to clean rooms have already been disclosed. For example, Patent Literature 1 is provided at the bottom of a work space of a clean room corresponding to an airflow passage, and an air circulation floor provided with holes,
An outside air inlet that is provided on the outer wall of the clean room, is connected to the outside air blowing duct and the ventilation system outside air conditioning box, and introduces outside air into the air flow passage;
A plurality of intake units provided in the airflow path;
A plurality of linear ventilation paths provided at the top of the work space of the clean room facing each of the intake units, and corresponding to the air flow paths,
An air flow supply system for a laminar flow type clean room is disclosed, comprising a plurality of filtration modules provided at the top of the work space of the clean room so as to face each of the linear ventilation paths.

  And in the clean room having this system, since each of the filtration modules mainly corresponds to the linear ventilation path, and each of the linear ventilation paths corresponds to the intake unit, an air flow is formed. That is, it is possible to save the usage amount of the blower fan, that is, it is possible to save costs such as power consumption and maintenance.

JP 2008-157607 A

However, the linear ventilation path in the clean room of Patent Document 1 is configured so that air is sent from the intake unit to the closed ventilation path end, and clean air is blown out from the filtration module due to the pressure increase in the linear ventilation path. Can not get a laminar flow. More specifically, when the ventilation area of the filtration module is large, the blowout from the vicinity of the intake unit of the linear ventilation path is strong, and the blowout from the end of the ventilation path is weak. In order to solve this problem, it is necessary to reduce the ventilation area of the filtration unit or extremely increase the air pressure from the intake unit. However, in any method, the wind speed blown out from the filtration unit becomes high, and a suitable laminar flow cannot be obtained. This is because if the wind speed becomes too fast, it hits a manufacturing apparatus arranged in the clean room, and the turbulent wind flow is not smoothly exhausted, so that a substantial laminar flow cannot be generated.

  Further, in Patent Document 1, a plurality of linear ventilation paths are arranged, but it is not easy to make the air pressure of each intake unit uniform, and a pressure difference occurs in the air blown out from the adjacent linear air paths, You cannot get a laminar flow. Moreover, even if a laminar flow is apparently formed, there is a high possibility that a turbulent flow will partially occur. Such a turbulent flow is undesirable because it causes volatile chemical substances and the like to stay in the clean room.

  As described above, it is a clean room where people enter and work, and it has not been easy to generate a substantial laminar flow.

  The present inventor has intensively studied in view of the above problems, and if the laminar flow has a wind speed of 0.1 to 0.15 m / sec, even if the manufacturing apparatus is disposed in the clean room, the substantial layer As a result, the present invention has been found to be suitable for removing dust and exhausting volatile chemical substances.

  That is, a clean room is provided that forms a laminar flow in a clean room by providing a chamber in the ceiling and changing the dynamic pressure of the air supplied to the chamber to a static pressure. More specifically, the clean room of the present invention includes a room composed of a floor, a wall and a ceiling, an air supply port arranged at the top of the ceiling or the wall, and an air discharge port arranged at the bottom of the floor or the wall. A floor grill disposed at a predetermined height above the floor; a chamber comprising a filter disposed at a predetermined height below the ceiling; and a space between the ceiling and the filter. It has a rectification | straightening material arrange | positioned in.

  According to such a configuration, the air flow that has passed through the filter in the clean room can be sent to the entire clean room in a laminar state.

  In addition to the above-described configuration, the clean room of the present invention further includes a blowing means for sending air from the outside air to the entire inner wall on the blowing side of the prefilter and air conditioner (AHU) through the HEPA filter to the supply port, It has a discharge means for sucking out air from the outlet and discharging it to the outside air.

  In this configuration, a chamber is provided in order to change all the dynamic pressure of the air blown from the blowing means through the duct to the ceiling of the clean room, and this chamber has an air flow that has passed through the filter in the clean room. Is provided with a rectifying means for easily making a laminar flow state, it is possible to form a uniform downflow laminar flow to the floor throughout the clean room. Here, a baffle (rectifying plate) or a punching metal (perforated plate) is preferably used as the rectifying means.

  In the clean room according to the present invention, the distance from the ceiling to the rectifier is in the range of 600 mm to 900 mm in the above configuration.

  According to such a configuration, an air flow in a wind speed range (0.1 to 0.15 m / sec) optimum for the clean room can be sent into the clean room as a laminar flow.

  Moreover, the clean room of the present invention has a light embedded in the wall in the configuration described above. In the present invention, in order to obtain a uniform downflow, unnecessary objects are not attached to the ceiling and floor for the operator. Therefore, in order to ensure illumination, it is necessary to embed the light in the wall.

  Further, in the clean room of the present invention, air supply ports arranged at the upper part of the wall are arranged to face each other. According to such a configuration, after passing through the filter in the clean room, the air flow is branched and the air flows having the same air volume and speed are made to collide with each other, so that the dynamic pressure is made static in the chamber. It is possible to achieve a laminar flow with a uniform wind speed in the clean room.

  According to the clean room of the present invention, it is possible to generate a laminar flow in a wind speed range of a predetermined (wind speed of 0.1 to 0.15 m / sec) suitable for a liquid crystal module or a PDP manufacturing process in the clean room. Therefore, the laminar flow of the down flow is hardly disturbed even in the vicinity of the manufacturing apparatus in the clean room. If the flow rate is laminar within this range, even if the manufacturing apparatus becomes an obstacle and the air flow is disturbed, the air flows in the lower grating (opening) without greatly affecting the surrounding air flow. Therefore, a substantially laminar flow can be obtained. In addition, even if the solvent used in the manufacturing process evaporates, the solvent stays in the clean room and does not diffuse, so that the work can be performed safely.

It is a perspective view which shows schematic structure of the clean room which concerns on one Embodiment of this invention. It is sectional drawing from the side which shows schematic structure of the clean room which concerns on one Embodiment of this invention. It is a perspective view which shows schematic structure of the clean room which concerns on other embodiment of this invention. It is sectional drawing from the side surface which shows schematic structure of the clean room which concerns on other embodiment of this invention. It is a figure which shows the relationship between the average wind speed of the airflow measured by the air supply in the clean room which concerns on one Embodiment of this invention, and the height under the ceiling in which the rectification | straightening means was arrange | positioned. It is a figure which shows the relationship between the average wind speed of the airflow measured by the air supply in the clean room which concerns on other embodiment of this invention, and the height under the ceiling in which the rectification | straightening means was arrange | positioned.

  Hereinafter, an embodiment of a clean room according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view showing the configuration of a clean room according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view from the side. However, in FIG. 2, for the sake of explanation, the mounting position direction of the exhaust fan is displayed by being different from that of FIG.

The clean room 1 of the present invention includes a room 10 composed of a floor 2, a wall 3 and a ceiling 8, an air supply port 11 disposed at the top of the ceiling 8 or the wall 3, and an air disposed at the bottom of the floor 2 or the wall 3. A discharge port 12, a floor grill 16 disposed at a predetermined height 15 above the floor 2, a medium performance filter 17 disposed at a predetermined height 19 below the ceiling 8, and a ceiling 8 and rectifying means 20 disposed between the medium performance filter 17 and the medium performance filter 17. A chamber 25 is formed by the ceiling 8, the medium performance filter 17, and the wall 3 between the medium performance filter 17 and the ceiling 8. A work space 18 is formed by the medium performance filter 17, the floor grill 16, and the wall 3 between the medium performance filter 17 and the floor grill 16.

  An air supply device 31 having a HEPA filter 33 and an air supply fan 32 is attached to the air supply port 11 via an air supply duct 34. A space 24 is provided below the floor grill 16 for exhaust treatment. In this space 24, an air exhaust port 12 is formed in the floor 2 or in the lower part of the floor. An exhaust duct 44 is connected to the air exhaust port 12, and is further connected to the exhaust device 41.

  Such a clean room 1 will be described in more detail with a focus on air flow. The air collected by the air supply fan 32 is trapped not only by dust but also by fine particles by the HEPA filter 33 and flows through the air supply duct 34 as clean air. Incidentally, the HEPA filter (High Efficiency Particulate Air Filter) is in accordance with JIS Z 8122, “It has a particle collection rate of 99.97% or more with respect to particles having a rated air volume and a particle size of 0.3 μm and an initial pressure. This is a filter defined as an “air filter having a loss of 245 Pa or less”.

  The HEPA filter 33 may be used in combination with a normal filter in the previous stage. Further, an ULPA filter (Ultra Low Penetration Air Filter) may be used.

  The purified air passes through the air supply duct 34 and enters the clean room from the air supply port 11 of the ceiling 8. In the clean room 1, a chamber 25 for obtaining a uniform down flow is formed in a space from the ceiling 8 to the medium performance filter 17. The chamber 25 is provided with rectifying means 20 for converting the dynamic pressure of the air entering from the air supply port 11 into a static pressure between the ceiling 8 and the medium performance filter 17. The higher the height 19 of the chamber 25 is, the better. However, since the volume of the chamber is increased, the amount of air blown is increased, so that the air supply fan 32 is enlarged and the power consumption is also increased.

  Therefore, the height 19 of the chamber should have an appropriate height that can maintain a wind speed of 0.1 m / sec to 0.15 m / sec in the clean room. In the clean room of the present invention, since the medium performance filter is disposed on the entire lower surface of the chamber 25, a certain height (a person can work) is required for maintenance and maintenance. From these conditions, the height from the ceiling 8 to the medium performance filter 17, that is, the chamber chamber height 19 is preferably 1600 mm or more, and more preferably 1800 mm.

  The rectifying means 20 provided in the chamber 25 is used for converting the dynamic pressure of the purified air entering the clean room 1 into a static pressure and obtaining a uniform down flow. As the rectifying means 20, a baffle (rectifying material) or a perforated plate is preferably used.

  The rectifying means 20 only needs to be formed of a material that does not generate dust, and plastic, metal, or the like can be suitably used. Moreover, the adsorptive sheet | seat which adsorb | sucks particles may be arrange | positioned on the surface.

When a baffle is used for the rectifying means 20, the size of the baffle is not particularly limited. However, the total area of all the baffles is preferably about 1/3 the area of the entire ceiling. This is because if the area is larger than this, the resistance against the air flow increases, and if it is narrow, a uniform down flow cannot be obtained in the entire clean room 1. Further, the baffles need not all have a uniform size, and the area below the air supply port 11 may be large and the area may be reduced as the distance from the air supply port 11 increases. If a baffle is provided immediately below the air supply port 11, the dynamic pressure of the air immediately below the air supply port 11 can be changed to a static pressure, and air blowing at a high wind speed can be prevented locally from the chamber chamber 18. it can.

  On the other hand, when a perforated plate is used for the rectifying means 20, it is preferable that the area of the portion of the frame other than the hole is about 1/3 as large as the entire ceiling. Further, the rectifying means 20 may use a baffle and a perforated plate at the same time.

  The height 21 from the ceiling 8 to the rectifying means 20 has a preferable height as will be described later. If it is too close to the ceiling 8, the wind pressure is applied locally and the function as a chamber cannot be performed. That is, a uniform downflow cannot be obtained. On the other hand, if it is too far from the ceiling 8, the middle performance filter inside the lower portion of the chamber 25 is directly hidden, the air flow rate increases, and the operation efficiency is poor. In addition, there is a place where air does not flow partially from the medium performance filter, and a uniform down flow cannot be obtained.

  A medium performance filter 17 is disposed on the entire lower surface of the chamber 25. This is for obtaining a uniform downflow in the clean room 1 and for removing particles that could not be removed by the HEPA filter 33 again to ensure air cleanliness in the clean room 1. Here, the medium performance filter 17 may be one shown in JIS B 9908 (ventilation air filter unit). Specifically, the filter can remove 60% or more or 90% or more of dust having a rough particle diameter of 2 μm.

  The air whose local flow is relaxed in the chamber 25 provided with the rectifying means 20 passes through the medium performance filter 17 and becomes a uniform down flow. Here, the uniform downflow means that almost the same wind speed can be measured no matter where the flow is measured on the floor surface of the clean room 1.

  Further, the downflow wind speed in the clean room 1 is preferably 0.1 m / sec to 0.15 m / sec. It is a wind speed at which dust generated by a person or a manufacturing apparatus is exhausted under the floor grille, and the solvent generated in the manufacturing process can be exhausted without stopping or diffusing. In addition, even if the wind speed in this range is obstructed by the production equipment, the air flow is exhausted under the floor grille without affecting the surrounding air flow. Can be obtained in a clean room. Therefore, if the wind speed is higher than this, the flow of the surrounding air is disturbed by the obstacle in the clean room, and there is a possibility that the volatile chemical substance or the like stays in the clean room. If the wind speed is slower than this, it is difficult to obtain a uniform laminar flow over the clean room.

  The floor grill 16 is preferably lattice grating. This is because if the floor grill 16 is dotted with through holes, the downflow itself is hindered. The material of the floor grill 16 is not particularly limited as long as it does not generate dust. Further, when a water-soluble paint or adhesive is used in the coating booth, the SUS material can be suitably used because it hardly causes rust.

  The size of the exhaust treatment space 24 under the floor is not particularly limited, but if the underfloor height 15 is narrow, a uniform downflow cannot be created.

  The air exhaust port 12 is preferably formed on the floor surface. However, since a space is required below the floor surface, the air exhaust port 12 can also be formed on the lower surface of the floor. The exhaust fan 42 needs to have the capacity to exhaust the same amount of air as the air supplied from the air supply port 11 from the air exhaust port 12 in consideration of the resistance of the exhaust duct 44. If there is much air supply, the air sent from the ceiling 8 will hit the floor 2, and will rise (turbulent flow) toward the ceiling. Moreover, if there is much exhaust, air will flow toward the vicinity of the air exhaust port 12, and a uniform downflow cannot be obtained.

  In addition, when a sufficient space cannot be taken under the floor surface, the plate material 15 is disposed in the grating portion above the air exhaust port 12. This is because if a sufficient space cannot be secured under the floor surface and the air exhaust port 12 is formed on the lower surface of the floor, the downflow near the floor grill on the upper surface of the air exhaust port 12 is disturbed. As described above, the exhaust treatment space 24 can be said to be a space for converting the static pressure laminar flow sent from the chamber 25 into the dynamic pressure exhaust drawn from the air exhaust port 12. In other words, in the clean room of the present invention, the dynamic pressure air sucked by the intake air is converted into a static pressure laminar flow in the chamber, and again converted from the static pressure laminar flow into the dynamic pressure exhaust gas in the exhaust treatment space 24.

  The clean room 1 of the present invention can be provided with an entrance 23 and a light 22. There may be two or more entrances 23, which are preferably opened outwardly from the clean room. Since the inside of the clean room is in a positive pressure state, it is difficult for air to enter from the outside even if the door is opened. On the other hand, when the door is opened inward, it becomes difficult to open the door with positive pressure in the event of an emergency in the booth.

  The light 22 is preferably embedded in the wall 3. This is because the chamber chamber 18 should have as few obstacles as possible in order to obtain a uniform downflow.

  3 and 4 are a perspective view and a cross-sectional view of the clean room in the case where the air supply ports are arranged facing the upper side of the wall. A duct 34 is pulled out from the air supply device 31 in two branches. Each of the ducts is connected to an air supply port 11a and an air supply port 11b that are provided on opposite walls of the chamber 25, respectively. Here, it is preferable that the air supply ports 11a and 11b are arranged at positions facing each other. In addition, the rectification | straightening means arrange | positioned between the ceiling 8 and the medium performance filter 17 shows the case of the perforated board 20a.

  As shown in FIGS. 3 and 4, when the air supply ports 11 a and 11 b are provided on the opposing walls of the chamber 25 in a positional relationship opposed to each other from the front, air from each air supply port collides in the middle of the chamber 25. The wind speed of the air that has passed through the duct is reduced. Furthermore, the air blown out from the hole in the perforated plate that is the rectifying means 20 can obtain a more uniform down flow than the case shown in FIGS.

  In addition, when forming an air supply port in the wall surface of the chamber 25, it is necessary to arrange | position to the ceiling side rather than the rectification | straightening means 20. FIG. This is because the rectifying means is installed in order to reduce the wind speed of the wind supplied from the air supply port and obtain a uniform downflow. Although not shown, the solvent and organic solvent sucked into the floor grill 16 are burned by a solvent recovery device or a solvent adsorption / concentration device to be rendered harmless without polluting the atmosphere.

Example 1
Next, an Example is shown about the clean room 1 of this invention. FIG. 5 shows the relationship between the wind speed in the clean room of the present invention and the position of the baffle. The clean room 1 has a size of 10 m × 10 m × 5 m and is a measurement result in the middle of the floor grill. The floor height 15 from the floor 2 to the floor grill was 1 m. The height below the ceiling from the ceiling 8 to the medium performance filter was fixed at 1800 mm (referred to as dimension A), and the distance 21 (referred to as dimension B) from the ceiling 8 to the rectifying means 20 was taken along the horizontal axis.

The baffle (flat plate) of the same area was used for the rectifying means 20 as a resin. The one baffle is 50cm square (0.25 m ^2), using 132 sheets of this, to form the baffle 20 of the total area of 33m ² relative to the ceiling area 100 m ^2. In addition, each board which forms a baffle was arrange | positioned at equal intervals on the ceiling 8 whole surface. In addition, the air supply and exhaust were adjusted to the same rate.

  This will be described with reference to FIG. The height 19 of the chamber 25 is fixed as the A dimension (1800 mm), the height of the baffle is set to the B dimension from the inner upper part of the chamber 25 to the baffle, and the height is changed within the A dimension of the chamber 25 to provide a clean room. When the wind speed in 1 was measured, the wind speed of the down flow became higher when the baffle was close to the ceiling. At this time, however, the downflow was not uniform depending on the location in the clean room 1.

  On the other hand, when the height of the baffle approaches the medium performance filter 17 (the B dimension increases), the wind speed decreases. This is probably because the apparent filter area has decreased. However, a stable laminar flow of 0.1 m / sec to 0.15 m / sec could be obtained when the distance from the ceiling 8 to the baffle was 600 mm to 900 mm.

  Under this wind speed, a laminar flow could be obtained substantially at a working height of 1 m or more from the floor grill even if a manufacturing apparatus or the like was placed in the clean room.

(Example 2)
FIG. 6 shows the relationship between the wind speed in the clean room of the embodiment and the position of the baffle when the two air supply ports 11 shown in FIG. 3 are arranged. The size of the clean room is 10 m × 10 m × 5 m, which is the same as in the first embodiment. The air supply ports 11a and 11b were arranged at opposing positions on the opposing walls of the chamber chamber 18. Here, the opposing positions mean that the air supply ports are formed at positions where the distance from the ceiling and the distance from the left and right walls are the same.

In this embodiment, the straightening means 20 is a perforated plate. The perforated plate was prepared so that the area of the frame portion other than the holes was about 33.5 m ² . More specifically, the rectifying means 10 is a plate of 10 m × 10 m, and a stainless punching metal having 160 circular holes with a radius of 39 cm is used. The area of the frame other than the holes was about 76.5 m ² .

  The air supply port was arranged at a position of 50 mm from the ceiling with a height of 300 mm and a width of 500 mm. As a result of the air supply port facing the wall, the wind in the chamber cancels each other, so the range in which a stable laminar flow of 0.1 m / sec to 0.15 m / sec can be obtained is 400 mm to 1000 mm from the ceiling. Spread to the range.

  The clean room of the present invention can be used for electronic components manufactured in a clean atmosphere for small items such as home appliances such as liquid crystal modules and PDP manufacturing as well as electronic components (display devices) using organic EL. .

DESCRIPTION OF SYMBOLS 1 Clean room 2 Floor 3 Wall 8 Ceiling 10 Room 11 Air supply port 12 Air exhaust port 15 Floor height 16 Floor grill 17 Medium performance filter 18 Work room 19 Chamber room height 20 Baffle (rectifier plate)
21 (from ceiling to baffle) 22 Light 23 Inlet 24 Exhaust treatment space 25 Chamber 30 Air blower 31 Air supply device 32 Air supply fan 33 HEPA filter 34 Air supply duct 40 Exhaust device 41 Exhaust device 42 Exhaust fan 44 Exhaust duct

Claims (7)

A room with a floor, walls and ceiling,
An air supply port arranged at the top of the ceiling or the wall;
An air outlet located at the bottom of the floor or the wall;
A floor grill disposed at a predetermined height above the floor; and
A chamber comprising a filter disposed at a predetermined height below the ceiling from the ceiling;
A clean room having rectifying means disposed between the ceiling and the filter.   The clean room according to claim 1, wherein the rectifying means is a baffle.   The clean room according to claim 1, wherein the rectifying means is a perforated plate.   The clean room according to any one of claims 1 to 3, wherein the air supply port is disposed to face an upper portion of the wall. Furthermore, a blowing means for sending air from outside air to the air supply port through a filter,
The clean room according to any one of claims 1 to 4, further comprising discharge means for sucking out air from the air discharge port and discharging it to outside air.   The clean room according to any one of claims 1 to 5, wherein a distance from the ceiling to the rectifying means is in a range of 600 mm to 900 mm.   The clean room according to claim 1, wherein a light is embedded in the wall.