JP3808567B2 - Clean room structure - Google Patents

Description

【００２９】
【実施例】
以下、本発明の効果を実験によって明らかにする。
１．実験方法
本発明に係るトンネル方式と従来のトンネル方式とで水平方向の気流性状を観察した。具体的には、図５に示されるように、生産ゾーンＡ側では吹出し速度０．３m/sec で清浄空気の吹出しを行い、非生産ゾーンＢではこれより吹出し速度を緩和させて（０．１m/sec 、０．１５m/sec ０．２m/sec の３ケース）吹出しを行い、床面側では吸込み速度を均一として空気を流した場合（本発明方式）と、図６に示されるように、生産ゾーンＡ側では吹出し速度０．３m/sec で清浄空気の吹出しを行い、非生産ゾーンＢではこれより吹出し速度を緩和させて（０．１m/sec 、０．１５m/sec ０．２m/sec の３ケース）吹出しを行い、床面側では生産ゾーンＡの気流速度、非生産ゾーンＢの気流速度に対応した吸込み速度として空気を流した場合（従来方式）とについて、領域境界部を中心としてその近傍位置の水平気流性状を超音波３次元風速計により観察するとともに、発塵源位置の高さを変えて塵埃を発生させてその拡散挙動を観察した。
【００３０】
２．実験結果
Ａ．水平方向の気流性状
天井面での吹出し速度を生産ゾーンＡ側（高風速領域）で０．３m/sec 、非生産ゾーンＢ側（低風速領域）で０．１５m/sec としたケースについて、中央の風速境界線からそれぞれの側に０．３ｍ離れた位置と０．９ｍ離れた位置とで水平方向気流の状態について測定を行い、本発明方式の結果を図７に、従来方式の結果を図８に示した。なお、図中、符号は高風速側から低風速側への流れを正としている。
【００３１】
実験結果から明らかなように、本発明方式の結果を示した図７においては、±０．３ｍ位置、±０．９ｍ位置のいずれの位置においても、天井面近傍（ＦＬ＋２．５ｍ）から床面直上（ＦＬ＋０．７ｍ）までのどの高さ位置であっても、生産ゾーンＡ（高風速領域）から非生産ゾーンＢ（低風速領域）に向かって気流の流れ出しが起きているのに対して、従来方式の結果を示した図８においては、ＦＬ＋１．３ｍ以上の高さでは生産ゾーンＡから非生産ゾーンＢに向かって気流の流れ出しが起きているのであるが、ＦＬ＋１．３ｍ以下になると、気流の方向が逆になり非生産ゾーンＢから生産ゾーンＡに向かって流れ込みが生じていることが判る。
【００３２】
Ｂ．塵埃拡散実験
天井面での吹出し速度を生産ゾーンＡ側（高風速領域）で０．３m/sec 、非生産ゾーンＢ側（低風速領域）で０．１５m/sec としたケースについて、塵埃発生器を風速境界線のＦＬ＋１．５ｍ、ＦＬ＋１．９ｍ、ＦＬ＋２．７ｍの各位置に設置して、塵埃の拡散程度を観察した。本発明方式の結果を図９に、従来方式の結果を図１０に示した。
【００３３】
実験結果から明らかなように、本発明方式の場合には、図９に示されるようにＦＬ＋１．５ｍより低いところでは塵埃が生産ゾーンＡから非生産ゾーンＢ側に流出するように拡散していることが確認されたのに対して、従来方式の場合には、図１０に示されるように生産ゾーンＡ側に流入するように塵埃が拡散していることが確認された。この結果は、上記水平方向の気流性状の結果を反映する結果となっている。
【００３４】
また、本発明方式の場合において、ＦＬ＋０．９ｍ位置での風速境界線から生産ゾーンＡ側への拡散距離Ｌを、非生産ゾーンＢ側領域の吹出し速度を０．２m/sec 、０．１５m/sec ０．１m/sec に変えた場合の各ケースについて測定し、その結果を表１に示す。
【００３５】
【表１】

【００３６】
表１より、発塵源高さＦＬ＋１．５ｍのケースにおいて、ＢパタンとＣパタンとで数値の逆転が見られるものの、全体的傾向として非生産ゾーンＢの吹出し速度が高い程、拡散距離Ｌが小さくなることが確認された。また、拡散距離Ｌはオーダー的に概ね４０cm以下とし得ることも同時に確認された。
【００３７】
【発明の効果】
以上詳説のとおり本発明によれば、トンネル方式のクリーンルーム構造において、風速境界近傍のどの高さ位置であっても高風速側領域から低風速側領域への流れ出しが生じるようになる。したがって、作業通路を人が歩いて塵埃が巻き上げられた場合でも、低風速側領域に塵埃が拡散するようになり、常に高風速側領域をより確実に高清浄度状態に維持し得る。
【図面の簡単な説明】
【図１】 第１実施例に係るクリーンルームの概略構造図である。
【図２】 その要部拡大図である。
【図３】 第２実施例に係るクリーンルームの概略構造図である。
【図４】 第３実施例に係るクリーンルームの概略構造図である。
【図５】 実施例における本発明方式の気流状態図である。
【図６】 実施例における従来方式の気流状態図である。
【図７】 本発明方式の水平方向気流性状図である。
【図８】 従来方式の水平方向気流性状図である。
【図９】 本発明方式の塵埃拡散状況の実験結果図である。
【図１０】 従来方式の塵埃拡散状況の実験結果図である。
【図１１】 従来のベイ方式によるクリーンルーム概略構造図である。
【図１２】 従来のトンネル方式によるクリーンルーム概略構造図である。
【符号の説明】
１…高性能フィルター、２…送風機、３…ケーシング、５…仕切り壁、６…グレーチング床、７…リタンプレナムエリア、１０・１１・１６・１７…空気抵抗体、ＷＺ…ワーキングゾーン、ＵＺ…ユーティリティゾーン、Ａ…生産ゾーン、Ｂ…非生産ゾーン。[0001]
BACKGROUND OF THE INVENTION
In the tunnel type clean room in which the clean room is partitioned into a high cleanliness region and a low cleanliness region, and the cleanliness is different in each region, the low cleanliness region generated at the boundary of the region is increased. The present invention relates to a clean room structure that prevents dust from flowing out to the cleanliness area side.
[0002]
[Prior art]
In semiconductor and film manufacturing factories and precision machinery factories, even a small amount of airborne particles can adhere to the product being manufactured and cause product defects. Maintain, work on product quality and reliability, and improve yield. A room cleaned for such a purpose is called a clean room, and a very high clean environment is secured.
[0003]
In the clean room, in order to keep the air clean, for example, a high performance filter is disposed on the ceiling or wall part, and a number of air discharge holes are formed on the floor or wall part, and circulated in the middle of the circulation path. A fan is provided to circulate air so as to go around the high performance filter.
[0004]
Conventionally, there are various types of air purification methods in a clean room, such as a down flow method and a bay method. The downflow type is also called the entire surface vertical laminar flow method, and a high-performance filter is arranged on almost one surface of the ceiling, while a floor is used as a grating to form a suction port so that the air fed from the back of the ceiling This is a system in which after passing through the performance filter and sent to the room, it is sucked from the suction port and circulated. In this case, the vertical air velocity is set to about 0.25 to 0.5 m / sec. If the blowing speed on the ceiling surface is 0.5 m / sec, the ventilation frequency is 400 to 600 times / h or more. . Although this method can maintain the cleanliness class 100 to 1 by a very effective means for removing fine particles, a huge amount of air must be circulated, and naturally the capacity of the air conditioning equipment does not increase. There is a problem that initial cost and running cost increase.
[0005]
On the other hand, as shown in FIG. 11, the bay method has a relatively low cleanliness by installing a working zone WZ in which production activities are actually performed in a clean room and a high cleanliness class is required, and facilities. The initial cost and running cost are reduced by partitioning it into a utility zone UZ, which is sufficient in the class.
[0006]
In recent years, this bay-type working zone can be used in the upper part of the production line that requires a strict cleanliness class (for example, class 100) or in the vicinity thereof, and a relaxed cleanliness class (for example, class 1000 or 10,000). A so-called tunnel method is adopted in which air conditioning facilities are planned separately for the passages. In this tunnel system, as shown in FIG. 12, a so-called tunnel unit is continuously suspended on the production line and divided into cleanliness classes such as A part and B part. Therefore, the vertical air velocity is set to about 0.1 to 0.2 m / sec. The surrounding A part is made into a high cleanliness class tunnel-like space, and the air supply in the work passage B part is reduced from the A part to relax the cleanliness class. In this case, the suction speed to the floor surface is the suction speed corresponding to the air flow speed, that is, suction is performed at a relatively fast speed in the A part, and suction is performed at a slow speed in the B part. As prior arts related to this method, there can be mentioned JP-A-56-162335, JP-A-59-185923, and Japanese Patent Application No. 1-245074.
[0007]
The JP 56-162335 and No. JP 59-185923 divides the clean room and the production line and the non-production line, in addition to operating the air supply ceiling Chang bar or al, relatively production The present invention relates to an invention in which the vertical airflow velocity on the line side is made larger than the vertical airflow velocity on the non-production line side, and the latter Japanese Patent Application No. 1-245074 is woven, non-woven fabric, wire mesh, perforated for high performance filters. The present invention relates to an invention in which air flow speeds on a production line side and a non-production line side can be arbitrarily adjusted by attaching air resistors such as plates in an overlapping manner.
[0008]
[Problems to be solved by the invention]
In the tunnel method, it is true that the production line area where the air velocity is increased is much more clean and the cost is reduced. It is the clean method most used in factories.
[0009]
However, the details will be clarified by the experiment described later. According to the experiments by the present inventors, particularly in the vicinity of the boundary between the production line area (high wind speed side area) and the non-production area (low wind speed side area). When the airflow condition was observed, the airflow was flowing from the high wind speed side area toward the low wind speed side area in the ceiling side area (approximately FL + 1.m or more), but on the floor side (approximately FL + 1.m or less). On the contrary, the new fact that the airflow flows from the low wind speed area toward the high wind speed area is found. Even if it is only in the vicinity of the floor side, the intrusion of dust toward the high wind speed side area means that, for example, when dust is rolled up at the intrusion position, the dust is in a wider range of the high wind speed side area. It means that dust can diffuse.
[0010]
Accordingly, an object of the present invention is to allow a flow from the high wind speed side region to the low wind speed side region at any height position in the vicinity of the wind speed boundary in the tunnel type clean room structure, and a person walks along the work passage. An object of the present invention is to provide a clean room structure in which even when dust is rolled up, the dust is diffused into the low wind speed side region so that the high wind speed side region can be more reliably maintained in a high cleanliness state.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides an air filter on the ceiling side, an air suction hole is formed on the floor surface, and clean air is rectified from the ceiling side to the floor side, and the entire vertical laminar flow is In a clean room that uses a flow method
The same space of this clean room is divided into a high cleanliness area and a low cleanliness area, on the ceiling blowout side; the blowout speed on the high cleanliness area side is 0.25 to 0.5 m / sec , and the low cleanliness while adjusting the blowing rate adjusting means so that 0.1 to 0.2 m / sec velocity blowing in degrees region side,
On the floor surface suction side; the suction speed adjusting means can be adjusted so that the suction speed to the floor surface on the high cleanliness region side and the suction speed to the floor surface on the low cleanness region side are substantially uniform ,
The blowing speed adjusting means is an air resistor attached to the air speed control of the blower disposed on the ceiling side of the air filter or the air filter, and the suction speed adjusting means is an air volume adjusting damper or floor provided on the floor lower side. It is the air resistor attached to .
[0012]
In this case , the suction speed to the floor surface from the supply / exhaust balance is a weighted average value considering the blowing speed on the high cleanliness area side, the blowing speed on the low cleanliness side, and the area ratio of each of these areas. Is good.
[0013]
In the case of the tunnel method that has been proposed in the past, even if the blowing speed from the ceiling surface is adjusted, the suction speed is adjusted on the floor surface side, and further on each side of the ceiling and floor surface. Even if the air velocity is adjusted, all the proposals to achieve a uniform laminar flow state with different wind speeds in the production zone (high wind speed region) and non-production zone (low wind speed region) are all. . Therefore, when both suction speeds are compared, it is necessary to set the suction speed corresponding to the airflow speed. Naturally, the suction speed is high on the production zone side and the suction speed is low on the non-production zone side.
[0014]
On the other hand, in the case of the invention of the present application, the production zone side is blown from the ceiling air filter surface as usual at a relatively high blowing speed, while the floor side is discharged at a uniform suction speed. To be adjusted. That is, the conventional method is “different wind speed blowing-different wind speed suction”, whereas the present invention is “different wind speed blowing-same wind speed suction”.
[0015]
From a macro perspective, the conventional method maintains a relatively high cleanness in the high wind speed region and a low cleanness in the low wind speed region. There have been no reports observed in the past, and it was generally considered that the initial objectives were sufficiently achieved. However, as will be apparent from the experiments described later, the experiments by the present inventors have shown that, in the floor side area (approximately FL + 1.m or less) of the boundary portion of each area, the low wind speed area moves from the high wind speed area. A new fact that the air current is flowing in was discovered. The present invention prevents this flow out to the high wind speed side region.
[0016]
In this specification, in the comparison between the production zone and the non-production zone, the production zone side is expressed as a high wind speed area or a high cleanliness area, and the non-production zone is expressed as a low wind speed area or a low cleanliness area. However, in the actual wind speed adjustment in each region, the air flow velocity in the production zone is set to a normal level (as it is), and the air flow velocity in the non-production zone is decreased to give a relative difference.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the clean room CR is partitioned into a working zone WZ and a utility zone UZ by a partition wall 5. The working zone WZ is a space where actual manufacturing operations are performed, and the utility zone UZ is a semi-clean area surrounding the working zone WZ in the clean room CR, which is also referred to as a service area and is the rear part of the manufacturing apparatus. It is a space where various utility pipes and ducts connected to it are connected. It also serves as a buffer zone that protects the working zone WZ from external contamination.
[0018]
In the working zone WZ, a small blower 2 is built in the casing 3 with respect to each frame portion of the ceiling frames 4, 4,... A fan filter unit that is integrated with a high-performance filter such as a filter or ULPA filter or an ultra-high-performance filter 1, 1,... (Hereinafter referred to as a high-performance filter) is attached. A complete air-tightness is secured around the high-performance filters 1, 1 ... in contact with the ceiling frames 4, 4 ... by a seal or the like.
[0019]
Further, the floor is a grating floor 6, and the clean air that has passed through the high-performance filters 1, 1,... , Also referred to as a return chamber.) After flowing into 7, it passes through the adjacent return duct 8 and is again supplied to the working zone WZ. On the other hand, in the utility zone UZ, indoor air is simply taken in by the extraction fan 9 and supplied to the ceiling back chamber to circulate the air.
[0020]
The working zone WZ is divided into a production zone A on the right side of the drawing where a work table, a manufacturing apparatus, etc. are installed and actually manufactured, and a non-production zone B on the left side of the drawing, which serves as a working passage, etc. On the A side, the blower speed V _A on the production zone A side is set to about 0.25 to 0.5 m / sec by inverter-controlling the motor rotation of the blower 2 to ensure class 100 cleanliness, On the other hand, since the class 1000 is sufficient on the non-production zone B side, the blowing speed V _B is set to about 0.1 to 0.2 m / sec.
[0021]
On the floor side of the working zone WZ, an air resistor 10 having a relatively large air resistance is installed on the production zone A side with respect to the lower surface side of the grating floor 6, and the non-production zone B An air resistor 11 having a relatively small air resistance is installed on the side. As the air resistors 10 and 11, paper, non-woven fabric, woven fabric, wire mesh, perforated plate (single plate or sliding double plate) and the like are preferably used, but any air resistance can be used. The air resistance values of the air resistors 10 and 11 disposed in the production zone A and the non-production zone B are linear functions of the air flow velocity V, but correspond to the air flow velocity of the clean air blown out from the high-performance filter 1. In the production zone A, one having a high air resistance is used, and in the non-production zone B, one having a low air resistance is used. The suction speed V _{C of the} floor surface due to the difference in air resistance between the air resistors 10 and 11 is used. (See FIG. 2) is adjusted to be substantially uniform. In this example, the air resistors 10 and 11 are provided in both the production zone A and the non-production zone B. Of course, the non-production zone B side is left as the grating floor 6, and the air resistance is only on the production zone A side. By providing the body 10, the floor suction speed V _C may be adjusted to be substantially uniform.
[0022]
Thus, by adjusting the blowing speed and the suction speed of the airflow, the production zone A on the side set to a high blowing speed is maintained in the high cleanliness region of class 100, for example, and as shown in FIG. In addition, a horizontal airflow (more precisely, the horizontal component of the airflow) from the production zone A side to the non-production zone B side is generated, and even if a person walks up the work path and dust is rolled up, In order to show the behavior of diffusing to the non-production zone B side without entering the production zone A side, a higher cleanliness is ensured more reliably on the production zone A side.
[0023]
Next, FIG. 3 shows a second embodiment according to the present invention, in which air is supplied to one ceiling backside air supply chamber 12 through the air supply duct 13, and one end of the retan chamber 15 under the floor. This is an air circulation system in which air is sucked from the duct suction port 14 formed in the above and circulated.
[0024]
In the second embodiment, the blowout speed adjustment from the high performance filter 1 is performed by the air resistors 16 and 17 attached to the high performance filter 1.
[0025]
On the other hand, in this air circulation system example, duct suction is performed only from one end portion of the return chamber 15, so the negative pressure level is different between the vicinity of the suction port and the remote position, and suction imbalance may occur. However, the air resistors 10 and 11 on the floor side can be installed in consideration of this suction imbalance. As shown in the figure, the design procedure in this case includes an air resistance gradient line (I) for making the negative pressure imbalance of the return chamber 15 uniform, and an air flow in the production zone A and the non-production zone B in the clean room. Because it is usually difficult to draw an air resistance line (III) that is superimposed on the air resistance line (II) to make the speed uniform, and then to obtain an air resistance body with a constant slope of air resistance value Then, a step-like design air resistance line along the superimposed air resistance line is determined, and a material of each air resistance body that can change the air resistance value stepwise is selected and arranged. In the illustrated example, both the production zone A and the non-production zone B are divided into two blocks, and the air resistors 10A, 10B, 11A, and 11B are arranged in descending order of air resistance from the duct suction port 14 side.
[0026]
As the suction speed adjusting means on the grating floor 6 side, a volume damper mechanism shown in FIG. 4 can be used. The return chamber under the grating floor 6 is divided into a plurality of small chambers 20, 20..., These small chambers 20, 20... And the return duct 22 communicate with each other. 21 can be provided, and the suction speeds of the production zone A and the non-production zone B can be made uniform by adjusting the opening of each of the volume dampers 21, 21. In this case, an air volume sensor or the like may be provided in each of the small chambers 20, 20... And the opening degree of each of the volume dampers 21, 21... May be automatically controlled based on information from these air volume sensors.
[0027]
By the way, the suction speed on the floor surface is calculated by the following formula (1) so that the blown air volume and the sucked air volume are balanced, and the blow speed V _A on the production zone A side and the blown air on the non-production zone B side. The weighted average value considering the speed V _B and the ratio of the area (A _A , A _B ) of each region is preferably used.
[0028]
[Expression 1]

[0029]
【Example】
Hereinafter, the effects of the present invention will be clarified through experiments.
1. Experimental Method Horizontal airflow characteristics were observed in the tunnel method according to the present invention and the conventional tunnel method. Specifically, as shown in FIG. 5, clean air is blown at a blowing speed of 0.3 m / sec on the production zone A side, and the blowing speed is reduced (0.1 m) in the non-production zone B. / sec, 0.15 m / sec 0.2 m / sec)) When blowing out and flowing air with the suction speed uniform on the floor side (the present invention method), as shown in FIG. On the production zone A side, clean air is blown at a blowing speed of 0.3 m / sec. In the non-production zone B, the blowing speed is reduced (0.1 m / sec, 0.15 m / sec, 0.2 m / sec). 3 cases) When air is blown out and air is flown as the suction speed corresponding to the airflow speed of the production zone A and the airflow speed of the non-production zone B on the floor side (conventional method), the region boundary is the center. The horizontal airflow characteristics in the vicinity are measured by an ultrasonic three-dimensional anemometer. With observation to observe the diffusion behavior by changing the height of the dust source position to generate dust.
[0030]
2. Experimental results A. Horizontal airflow characteristics The case where the blowing speed on the ceiling surface is 0.3 m / sec on the production zone A side (high wind speed area) and 0.15 m / sec on the non-production zone B side (low wind speed area) The horizontal airflow state was measured at a position 0.3 m away and 0.9 m away on each side from the wind speed boundary line, and the results of the method of the present invention are shown in FIG. 7 and the results of the conventional method are shown. This is shown in FIG. In the figure, the sign is positive for the flow from the high wind speed side to the low wind speed side.
[0031]
As is apparent from the experimental results, in FIG. 7 showing the results of the method of the present invention, the floor surface from the vicinity of the ceiling surface (FL + 2.5 m) at both the ± 0.3 m position and the ± 0.9 m position. At any height position up to just above (FL + 0.7m), airflow is flowing from production zone A (high wind speed region) to non-production zone B (low wind speed region), In FIG. 8 showing the result of the conventional method, the flow of airflow from the production zone A toward the non-production zone B occurs at a height of FL + 1.3 m or more. It can be seen that the direction of is reversed and inflow occurs from the non-production zone B toward the production zone A.
[0032]
B. Dust diffusion experiment Dust generator for a case where the blowing speed on the ceiling surface is 0.3 m / sec on the production zone A side (high wind speed region) and 0.15 m / sec on the non-production zone B side (low wind speed region). Was installed at each position of FL + 1.5m, FL + 1.9m, FL + 2.7m on the wind speed boundary line, and the degree of dust diffusion was observed. The result of the method of the present invention is shown in FIG. 9, and the result of the conventional method is shown in FIG.
[0033]
As is clear from the experimental results, in the case of the method of the present invention, as shown in FIG. 9, dust is diffused so as to flow out from the production zone A to the non-production zone B side at a position lower than FL + 1.5 m. On the other hand, in the case of the conventional method, it was confirmed that dust was diffused so as to flow into the production zone A side as shown in FIG. This result reflects the result of the horizontal airflow property.
[0034]
In the case of the method of the present invention, the diffusion distance L from the wind speed boundary line at the FL + 0.9 m position to the production zone A side is set to be the blowing speed in the non-production zone B side region is 0.2 m / sec, 0.15 m / Measurement was made for each case when sec was changed to 0.1 m / sec, and the results are shown in Table 1.
[0035]
[Table 1]

[0036]
From Table 1, in the case where the dust generation source height is FL + 1.5 m, the numerical value is reversed between the B pattern and the C pattern. However, as the overall tendency, the diffusion speed L increases as the blowing speed of the non-production zone B increases. It was confirmed to be smaller. It was also confirmed at the same time that the diffusion distance L could be about 40 cm or less in order.
[0037]
【The invention's effect】
As described above, according to the present invention, in the tunnel type clean room structure, the flow from the high wind speed side region to the low wind speed side region occurs at any height position near the wind speed boundary. Therefore, even when a person walks along the work path and the dust is wound up, the dust diffuses into the low wind speed side region, and the high wind speed side region can always be maintained in a highly clean state more reliably.
[Brief description of the drawings]
FIG. 1 is a schematic structural diagram of a clean room according to a first embodiment.
FIG. 2 is an enlarged view of a main part thereof.
FIG. 3 is a schematic structural diagram of a clean room according to a second embodiment.
FIG. 4 is a schematic structural diagram of a clean room according to a third embodiment.
FIG. 5 is an airflow state diagram of the method of the present invention in an example.
FIG. 6 is an airflow state diagram of a conventional system in an example.
FIG. 7 is a horizontal airflow property diagram of the method of the present invention.
FIG. 8 is a horizontal airflow property diagram of a conventional method.
FIG. 9 is an experimental result diagram of the dust diffusion state of the method of the present invention.
FIG. 10 is an experimental result diagram of a conventional dust diffusion state.
FIG. 11 is a schematic structural diagram of a clean room using a conventional bay method.
FIG. 12 is a schematic structural diagram of a clean room by a conventional tunnel method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... High performance filter, 2 ... Blower, 3 ... Casing, 5 ... Partition wall, 6 ... Grating floor, 7 ... Ritamplenum area, 10.11.16.17 ... Air resistor, WZ ... Working zone, UZ ... Utility Zone, A ... production zone, B ... non-production zone.

Claims (2)

In a clean room where an air filter is installed on the ceiling side, an air suction hole is formed on the floor surface, and clean air flows in a rectified state from the ceiling side to the floor side in an entirely vertical laminar flow system ,
The same space of this clean room is divided into a high cleanliness area and a low cleanliness area, on the ceiling blowout side; the blowout speed on the high cleanliness area side is 0.25 to 0.5 m / sec , and the low cleanliness while adjusting the blowing rate adjusting means so that 0.1 to 0.2 m / sec velocity blowing in degrees region side,
On the floor surface suction side; the suction speed adjusting means can be adjusted so that the suction speed to the floor surface on the high cleanliness region side and the suction speed to the floor surface on the low cleanness region side are substantially uniform ,
The blowing speed adjusting means is an air resistor attached to the air speed control of the blower disposed on the ceiling side of the air filter or the air filter, and the suction speed adjusting means is an air volume adjusting damper or floor provided on the floor lower side. A clean room structure characterized by being an air resistor attached to . 2. The clean room structure according to claim 1, wherein the suction speed to the floor surface is a weighted average value in consideration of the blowing speed on the high cleanliness region side, the blowing speed on the low cleanliness side, and the area ratio of each of these regions.

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