JPS61282742A - Clean room - Google Patents

Abstract

PURPOSE:To widely secure the effective space for the flowing conditions of a laminar flow of a clean gas in a high-degree clean zone and improve the cleaning degree of a low-degree clean zone by providing a third blow-off port through which a clean gas is downwardly blown off, and disposing a second blow-off port so that the clean gas blow-off flow line is directed toward an oblique downward direction in which the lower part is gradually spaced further from the bordery zone. CONSTITUTION:The flow speed in a bordery zone C of a clean gas blown off perpendicularly downward from a third blow-off port 16 is set by the adjustment of a damper 18 in such a manner that the flow speed of the clean gas therein becomes substantially equal to that of the clean gas at a portion located on the side of the bordery zone C within a high-degree clean zone. Accordingly, it is made possible to widely secure over the whole zone an effective space in which the flowing condition of the laminar flow is stable without disturbing the clean air flowing condition in the high-degree clean zone A by the clean air blow-off through a third blow-off port 16. Further, since the clean air blown off from the second blow-off port 4 assumes a direction obliquely downward toward the central side in the tunnel width direction of a low- degree clean zone B, invasion of adhering dusts and dirts can be effectively prevented even if the operator approaches the high-degree clean zone A.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a clean room used for various clean atmosphere operations such as LSI manufacturing, ultra-precision mechanical parts manufacturing, and chemical manufacturing. A first outlet that blows out clean gas almost vertically downward in a laminar flow over the entire indoor highly clean area where items that need to be kept clean are located, and an area for workers adjacent to the highly clean area. The present invention relates to a clean room provided with a second air outlet for blowing and supplying clean gas to a low-level clean area of the room.

[Conventional technology]

Conventionally, in the above-mentioned clean room, as shown in Figs. 4 and 5, the second air outlet (4) is locally connected to the ceiling of the room corresponding to the low-grade clean area (B). ,
Alternatively, a plurality of them can be distributed and arranged, and the second outlet (4)
The system is configured so that clean gas is blown out and supplied to the low-level clean area (B) in a diffusive manner, thereby covering almost the entire surface of the indoor ceiling corresponding to the low-level clean area (B) as a secondary gas.
The clean gas supply equipment for the low-level clean area (B) is simplified compared to a configuration in which the blow-off port is configured to blow and supply clean gas in a laminar flow over the entire area of the low-level clean area from the second blow-off port. The aim was to reduce the overall equipment cost by making the system more compact and compact.

However, if the configuration is such that the clean gas is simply blown out diffusely from the second outlet (4) in the ceiling as described above, the laminar clean gas flow in the high clean area (A) and the low clean gas flow ( Because the wind direction and wind speed are different from the clean gas flow in B), a vortex is generated at the boundary between definitions (A) and (11), and the vortex causes a transition from the low-level clean area (B) to the high-level clean area. (A)
The highly clean area (A) becomes contaminated due to dust intrusion into the area.

Therefore, as a measure to prevent contamination of the highly clean area (A) due to vortex flow, as shown in Figure 4,
, a hanging wall (19) is installed between (11), or a fifth
As shown in the figure, a third clean gas outlet (16) was attached to form a high-speed airflow curtain (F) at the boundary between the definitions (A) and (B).

In addition, in FIG. 4 and FIG. 5, (2), (5), and (17) are the first, second, and third outlet (1),
(4).

(16) is equipped with a high-performance filter, (7) is the air supply duct from the air conditioner to each outlet (1), (4), and (16), and (9) is the room adjacent to the highly clean area (A). A first exhaust port provided at the lower end of the wall (B), (10) a second exhaust port provided on the floor corresponding to the low-grade clean area (B),
(13) is a fan that circulates and supplies exhaust gas from the first exhaust port (9) to the first outlet (1), and (14) is a fan that returns exhaust gas from the second exhaust port (10) to the air conditioner. (15) is a highly clean area (
This is the workbench installed in A) (I cannot show the literature).

[Problem that the invention seeks to solve]

However, simply installing a hanging wall cannot sufficiently suppress the generation of vortices at the boundary between the highly clean area and the low clean area, and cannot sufficiently prevent dust from entering the highly clean area due to the vortex. In particular, when a worker located in a low-level clean area approaches a high-level clean area, a strong vortex is generated at the boundary between the high-level clean area and the low-level clean area due to the worker's presence.
Furthermore, since a large amount of dust is generated by the workers, the cleanliness of the highly clean area is significantly reduced.

On the other hand, if a high-speed airflow forms a curtain at the boundary between a highly clean area and a low-level clean area, the high-speed gas flow forming the airflow curtain will cause Because the clean gas laminar flow state in the side part is disturbed, the dust removal function within the area due to the clean gas laminar flow is impaired, and the cleanliness of the highly clean area decreases, and the laminar flow in the highly clean area The problem arises that the effective space where the flow condition is stable becomes narrow, and when workers are close to the highly clean area, extremely violent vortices can occur due to the collision between the high-speed gas that forms the airflow curtain and the workers in the vicinity. As a result, the deterioration in cleanliness in the highly clean area caused by nearby workers could be even worse than in the case of the above-mentioned hanging wall installation.

Moreover, in the case of the configuration shown in FIG. 4 and FIG. ), a large vortex occurs due to the diffusive blowout from the second outlet (4), and as a result, the cleanliness of the low-grade clean area (B) also decreases, This also promoted contamination of the highly clean area (A).

The purpose of the present invention is to rationally improve the clean gas blowing configuration, thereby making it possible to maintain a high level of cleanliness in the highly clean area while making the clean gas blowing equipment for the low clean area as simple and compact as possible. The object of the present invention is to secure a wide effective space in which the clean gas laminar flow state is stable in the highly clean area, and also to improve the cleanliness of the low clean area.

[Means for solving problems]

The clean room according to the present invention is characterized by a high-level clean area that receives clean gas in a laminar flow almost vertically downward from the first outlet, and a low-level clean area that receives clean gas from the second outlet. Clean gas is blown downward to the boundary area with the variable area so that the airflow condition in the boundary area is approximately the same speed and direction as the airflow condition in the highly clean area. Installing a third blowout port 1, the second blowout port is arranged near the third blowout port and in such a way that the clean gas blowout streamline is oriented diagonally downward, further away from the boundary area as it goes downward. The functions and effects are as follows.

[For production]

In other words, as shown in Fig. 2, the flow of clean gas in the boundary area (C) caused by the clean gas blowing out from the third outlet (16) is between the highly clean area (A) and the low clean area (B). Because it acts as a partition wall against
Dust intrusion from B) into the highly clean area (A) is very effectively avoided.

In addition, the flow of clean gas in the boundary area (C) is expressed as the image change area (A).
, If the barrier wall is simply applied to (B),
As shown in Figure 5, there is no difference in function from the conventional configuration that forms a high-speed airflow curtain (F), but the boundary area (C)
Since the airflow condition in the highly clean area (A) is almost the same speed and direction as the airflow condition in the highly clean area (A), the part of the highly clean area (A) facing the boundary area (C) The clean gas laminar flow in the boundary zone (C) is not disturbed by the clean gas flow in the boundary zone (C), and as a result, the dust removal function in the area by the clean gas laminar flow in the highly clean zone (A) is improved. In addition, a wide effective space in which the laminar flow state is maintained and stabilized can be secured over almost the entire area of the highly clean area (A).

In addition, the second outlet (4) for blowing and supplying clean gas to the low-grade clean area (B) is located near the third outlet (16), and the clean gas outlet streamline is located closer to the boundary toward the lower side. Area (C
), so it is placed diagonally downward, away from
The clean gas blown out from the second outlet (4) is in the boundary area (C)
Thereby, the above-mentioned partition effect due to the clean gas flow in the boundary area (C) and the clean gas flow from the third outlet (16) in the boundary area (C) are not disturbed. It is possible to continuously maintain a good condition in which the airflow flows at approximately the same speed and in approximately the same flow direction as in the highly clean area (A), and there is no vertical air flow between the highly clean area and the low clean area. Even if there is a wall structure, no vortex is generated at the corner between the indoor ceiling on the low-grade clean area side and the hanging wall structure.
As a result, the dust removal function in the low cleanliness area can also be improved, which in turn contributes to maintaining the cleanliness of the high cleanliness area.

Furthermore, even if the worker approaches the highly clean area (A), the air velocity in the boundary area (C) is considerably smaller than the air velocity of the conventional high-speed air curtain.
There is no generation of extremely violent eddy currents, such as those caused by the collision of high-speed gas forming a high-speed airflow curtain with nearby workers, and even if some boiling occurs due to the presence of nearby workers, the lower the boundary Due to the flow of clean gas in the low clean area (B) away from the clean area (C), dust intrusion into the high clean area (A) is effectively prevented.

Furthermore, as described above, the second outlet (4) is connected to the third outlet (1).
6) Because it is locally arranged nearby, the clean gas supply equipment for the low-grade clean area (B) can be simplified and compacted to almost the same degree as the conventional configuration shown in FIGS. 4 and 5,
The overall equipment cost can be maintained at approximately the same level as that of the conventional configuration shown in FIG. 5, which is provided with an outlet for forming a high-speed airflow curtain.

〔Effect of the invention〕

As a result of the above, the cleanliness of the highly clean area can be maintained at an extremely high level, which not only improves the quality of products such as LSIs and ultra-precision mechanical parts, but also greatly reduces the occurrence of defective products.
Furthermore, since it is possible to secure a wide effective space in the highly clean area where items required for cleanliness maintenance are located, work efficiency can be improved, and the overall configuration of the clean room can be made more compact, improving the ease of installation of the clean room. The equipment cost is almost the same as the conventional configuration, and as a whole, it is a lean room that is extremely advantageous in practical terms.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

Figures 1 and 2 show a so-called clean tunnel that forms a manufacturing line for LSIs, ultra-precision mechanical parts, etc. In a tunnel-shaped room, a highly clean area (A) where manufactured products are located is located in the direction of the tunnel 111. A low-grade clean area (B), which serves as a passage area for workers, is placed at both ends and in the center of the tunnel, and these areas (A) and (B) are extended in the longitudinal direction of the tunnel. There is.

A first outlet (1) that blows out clean air in a laminar flow almost vertically downward over the entire area of the highly clean area (A) is configured with a discharge side opening of a high-performance filter (2), and the first
An air outlet (1) and a first air supply chamber (3) for it are installed in the tunnel-shaped room above the highly clean area (A) and extend in the longitudinal direction of the tunnel, and in the low clean area (B). A second outlet that blows out clean air in a diffusive manner (
4), and a high-performance filter (5) for the second air outlet (4); an internal second air supply chamber (6) extending in the longitudinal direction of the tunnel in the ceiling of the tunnel-shaped room; Second air supply chamber (3), (6)
An air supply duct (7) from an air conditioner is connected to each of the air conditioners.

A first exhaust port (9) is provided at the lower end of both chamber walls (B) in contact with the highly clean area (A), and a lattice-shaped exhaust port (9) is provided on the indoor floor corresponding to the low clean area (B). 2 exhaust port (10),
Each of them is provided to extend in the longitudinal direction of the tunnel, and part of the exhaust air from the first exhaust port (9) and the exhaust air collected from the second exhaust port (10) into the floor exhaust chamber (11). A fan (13) is provided to circulate and supply air to the first air supply chamber (3) through a double-walled circulation air passage (12), and the remainder of the exhaust air collected in the floor exhaust chamber (11) is provided. The return air/exhaust duct (14) that carries the air to the air conditioner or exhausts it outside the system is connected to the floor exhaust chamber (14).
1) is connected.

In other words, the cleanliness of the highly clean area (A) is maintained at a high level by blowing and supplying clean air in a vertically downward laminar flow from the first outlet (1) over the entire area of the highly clean area (A). Part of the clean air supplied from the first outlet (1) is exhausted from the first exhaust port (9), and the remaining part is exhausted from the second exhaust port (10) together with the clean air supplied to the low-grade clean area (B). It is configured to do so.

Further, the exhaust air from the first exhaust port (9) and a part of the exhaust air from the second exhaust port (10) are circulated and supplied from the first outlet (1) to the highly clean area (Δ). By making it
While reducing the amount of air processed on the air conditioner side as much as possible to make the equipment configuration more compact, it is possible to supply a large amount of clean air to the highly clean area (A) in order to maintain the cleanliness of the highly clean area (A). It is configured.

In the figure, (15) is a workbench installed in the highly clean area (A) for manufacturing LSI and ultra-precision mechanical parts.

Boundary area between highly clean area (A) and low clean area (B) <C)
A third outlet (1) that blows clean air vertically downward
6) as the air supply chamber for the second
The air supply chamber (6) is also used to extend in the longitudinal direction of the tunnel, and the flow velocity in the boundary area (C) of clean air blown vertically downward from the third outlet (16) is as follows:
The blowout flow rate from the third outlet (16) is adjusted by adjusting the damper (18) so that the clean air flow rate is almost equal to the clean air flow rate in the part of the highly clean area (A) located on the boundary area (C) side. With this setting, the altitude is increased from the low-level clean area (B) where the worker is located due to the partition effect of the clean air discharged downward from the third outlet (16) and flowing through the boundary area (C). It is designed to prevent dust from entering the clean area (A).

In addition, by setting the vertically downward blow from the third air outlet (16) and the blowing flow velocity as described above, the flow state of clean air in the boundary area (C) can be changed to that in the highly clean area (A). In particular, the flow state of clean air in the area located on the boundary area (C) side of the highly clean area (A) is set to be a flow state in which the wind direction and wind speed are approximately the same. The clean air flow state in the clean area (A) is
A stable laminar flow state is maintained without disturbance by blowing clean air from the air outlet (16), and the dust removal function in the highly clean area (A) is maintained at a high level due to the laminar flow of clean air. At the same time, an effective space in which the clean air laminar flow state is stable can be widely secured throughout the highly clean area (A).

In the figure, (17) is a high-performance filter for the third outlet (16).

When arranging the second air outlet (4) for the low-level clean area (B), it is necessary to install the second air outlet (4) for the low-level clean area (B) in the indoor ceiling part located corresponding to the low-level clean area (B) when viewed in the tunnel longitudinal direction [both ends in the tunnel width direction, That is, the second air outlet (4) is locally arranged in a position close to the third air outlet (16), and the clean air is directed from the arrangement position toward the central part of the low-level clean area (B) in the direction of the tunnel 11. The second air outlet (4) is configured to blow out diagonally downward in a diffusive manner.

In other words, by arranging the second outlet (4) locally as described above, it is possible to simplify the clean air supply equipment for the low-level clean area (B), and also to simplify the clean air supply equipment for the low-level clean area (B) as a worker passage area. In order to ensure a high ceiling height of 1, and by blowing out clean air from the second outlet (4) in a diffusive manner, the second outlet (4)
4) is arranged locally, yet clean air can be uniformly supplied throughout the low-grade clean area (B).

Furthermore, by directing the clean air from the second outlet (4) diagonally downward toward the center of the tunnel in the low-level clean area (B), the flow of clean air in the boundary area (C) is improved. The condition is not disturbed by the clean air blowing out from the second outlet (4), and the above-mentioned partition effect due to the clean air flow in the boundary area (C) and the highly clean area (A
), so that workers located in the low clean area (B) can maintain the laminar flow state well in the high clean area (A).
), dust may enter the highly clean area (A) caused by nearby workers due to the flow of clean air in the low clean area (B), which moves further away from the boundary area (C) toward the bottom. It is designed to effectively prevent

[Another example]

Next, another embodiment of the present invention will be described.

1st to 3rd outlet (1), (4), (16)
The specific structure of can be improved in various ways, for example, as shown in FIG.
These may be configured as one blow-off unit whose blow-off surfaces are continuous and equipped with a filter (5) that also serves as a filter (5).

The present invention can also be applied when two or more sides of the circumference of the highly clean area (A) are adjacent to the low clean area (B), and the overall shape of the clean room and the specific use of the clean room are No questions asked.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, with FIG. 1 being a broken perspective view and FIG. 2 being an enlarged sectional view of the main part. FIG. 3 is an enlarged sectional view showing another embodiment of the present invention. FIGS. 4 and 5 are enlarged sectional views showing conventional examples, respectively. (A)...Highly clean area, (B)...Low clean area, (C)...Boundary area, (1)...
...First air outlet, (4)...Second air outlet, (1
6)...Third air outlet.

Claims (1)

[Claims] A first system that blows out clean gas almost vertically downward in a laminar flow over the entire highly clean area (A) in the room.
A clean room provided with an air outlet (1) and a second air outlet (4) for blowing and supplying clean gas to an indoor low level clean area (B) adjacent to the high level clean area (A), Regarding the boundary area (C) between the highly clean area (A) and the low clean area (B), the airflow condition in the boundary area (C) is approximately the same as the airflow condition in the highly clean area (A). A third outlet (16) is provided to blow out clean gas in a downward direction so as to create an airflow state at the same speed and in approximately the same flow direction.
) is arranged near the third blow-off port (16) and such that the clean gas blow-out streamline is oriented diagonally downward and farther from the boundary area (C) as it goes lower.