JPH01281352A - Blowing method for purified air in clean room - Google Patents

Abstract

PURPOSE:To prevent the ascending air current of purified air, which is caused in a clean room, and to maintain high cleanliness by forming a cold air layer within a underfloor chamber. CONSTITUTION:Air in a ceiling chamber 12 is sucked into each of suction boxes 14 and passes through HEPA (high performance) filters 18 to be blown into a clean room 20 wherein the purified air flows down and passes through a grating floor 22 to be sent into an underfloor chamber 26. In this instance, there is a case where the purified air is warmed up by heat generated from equipment and the like or by heat generated artificially, and such warmed air once passes through the floor 22 by an inertial force to be sucked into the chamber 26. Since the warmed air is cooled down on the surface of a cold air layer A within the chamber 26, however, it does not ascend again from the chamber 26 into the clean room 20. The warmed air flows on the surface of the cold air layer A to be discharged through an opening 30 or into a circulation pipe 40. Accordingly, the downflow of the purified air is sufficiently maintained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for blowing clean air in a clean room.
In particular, the present invention relates to a method for blowing clean air in a clean room that uses cold air to maintain cleanliness.

[Prior art]

No semiconductor manufacturing! ! Due to the environmental requirements, its manufacture is usually carried out in a clean room. Generally, in a clean room, air is blown into the clean room through multiple HEPA (high performance) filters installed on the ceiling, and the air in the room is sucked in from the floor with a ventilation structure and then passed through the HEPA filters on the ceiling. An air circulation system is adopted in which clean air flows down inside the room, creating a laminar flow.

[Problem that the invention seeks to solve]

By the way, high cleanliness can be obtained in a clean room when clean air is in a laminar flow state, and if the laminar flow is disturbed, the cleanliness level will be reduced. However, when clean air is heated by heat generated by equipment installed in the clean room or by workers, the heated air is temporarily exhausted into the underfloor chamber, but if it remains in the underfloor chamber,
It becomes an upward flow and flows into the room again, contaminating it. In the conventional method of blowing clean air in a clean room, there is a problem that such an upward flow cannot be prevented.

Furthermore, it has been considered to form an air curtain in a clean room to cover the surroundings of the emitting equipment. However, when forming an air curtain in a clean room, the wind speed of the air forming the curtain is faster than the surrounding wind speed, which causes problems such as disturbing the laminar flow of clean air in the clean room and reducing cleanliness. .

The present invention was made in view of the above circumstances, and it is an object of the present invention to propose a method for blowing clean air in a clean room that can maintain a high level of cleanliness by preventing the upward draft of clean air generated within the clean room. The purpose is

[Means for solving problems]

In order to achieve the above object, the present invention forms an underfloor chamber between a foundation floor and a breathable floor surface laid above the foundation floor, blows out clean air from the ceiling surface, and The method for blowing clean room clean air into the underfloor chamber through the permeable floor surface is characterized in that a cold air layer is formed within the underfloor chamber.

[Effect]

According to the method for blowing clean air in a clean room according to the present invention, the cold air layer in the underfloor chamber of the clean room cools the clean air heated by the heating element in the clean room, and the air flows into an upward air stream. Prevent this from happening. Therefore, the downflow of clean air is always maintained in the clean room.

Furthermore, if the air in the air curtain flow in the clean room is used as cooling air, the cooling air descends from the ceiling surface at a gentle speed to form an air curtain. Therefore, the cooling air curtain does not affect the surrounding air flow, so it does not disturb the laminar flow within the clean room.

〔Example〕

Preferred embodiments of the method for blowing clean air in a clean room according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram of a method for blowing clean air in a clean room according to the present invention. As shown in FIG. 1, a ceiling chamber 12 is formed in the clean room 10, and the ceiling chamber 12 is provided with a plurality of air supply boxes 14, 14, . . . . Each air supply box 14 is provided with an air supply fan 16. A HEPA filter 18 is attached to the bottom surface of each box 14. The air in the ceiling chamber 12 is passed through the air supply box 14 to a plurality of HEPA filters 18, 18,
It is blown out into the clean room 20 through...

Clean air in the clean room 20 flows down and is sucked in from the grating floor 22. An underfloor chamber 26 is formed between the grating floor 22 and the foundation floor 24, and a water-cooled air cooling bag 128 is provided in the underfloor chamber 26. As shown in FIG. 1, the air in the lower part of the underfloor chamber 26 is cooled by a cooling device 28 to form a cold air layer A.

The air in the underfloor chamber 26 passes through the side opening 30 to the passage 3.
Sent to 2. The air in the passageway 32 is routed back into the ceiling chamber 12 through the top opening 34, thereby circulating the air within the clean room 20.

Also, some of the air in the underfloor chamber 26? ! ring vibrator 4
0 and sent to the air conditioner 42.

The air conditioner 42 mixes and controls the humidity of the air from the outside air intake pipe 44 and the air from the circulation pipe 40 to supply air to the air supply pipe 4.
8 to the ceiling chamber 12 again. still,
? An air volume control valve 50 is installed on the Hl vibe 40 and the air supply pipe 48.
．． 50 are provided.

According to the method for blowing clean air in a clean room according to the present invention configured as described above, the air in the ceiling chamber 12 is sucked into each air supply box 14 and the HEPA filter 18
The air is blown out into the clean room 20 through the air. Clean air is downflowed in the clean room 20 and sent through the grating floor 22 into the underfloor chamber 26 .

In this case, the clean air may be warmed by heat generated by equipment or the like in the clean room 20 or by artificial heat generation, but the heated air is once sucked into the underfloor chamber 26 through the grating floor 22 due to inertial force. However, since the heated air is cooled on the surface of the cold air layer A within the chamber 26, it does not rise again from the underfloor chamber 26 into the clean room 20. Then, the warmed air passes through the surface of the cold air layer A and is discharged to the opening 30 or the circulation pipe 40. Therefore, even if there is an artificial heating element in the clean room 20, a sufficient downward flow of clean air is maintained.

FIG. 2 is an explanatory diagram of a second embodiment of the method for blowing clean air in a clean room according to the present invention. The clean room 60 shown in FIG. 2 has approximately the same structure as the clean room 10 shown in FIG.
The same reference numerals are given to the same members as those shown in , and detailed explanation thereof will be omitted.

The clean room 60 differs from the clean room 10 in FIG. The air supply box 14A is located at a position forming an air curtain in the clean room 20.

According to the method for blowing clean air in a clean room according to the present invention configured as described above, the cooled clean air in the air supply box 14A flows downward to form the air curtain B. Since the air in this air curtain B is a cooled natural descending flow, there is no risk of disturbing the surrounding clean air flow and causing convection or the like.

Further, the cooled clean air forming the air curtain forms a cold air layer A in the underfloor chamber 26. This cold air layer A has the same function and effect as the clean room 10 shown in FIG. 1, and can prevent the upward flow of clean air caused by an artificial heating element generated in the clean room 20.

FIG. 3 is an explanatory diagram of a third embodiment of the method for blowing clean air in a clean room according to the present invention. The clean room 70 shown in FIG. 3 has approximately the same structure as the clean room 10 shown in FIG. ? = items are given the same reference numerals and detailed explanation thereof will be omitted.

As shown in FIG. 3, a heat generating device 72 that emits heat is provided in the clean room 20, and a cooling device 28 is attached to the upper surface of the heat generating device 72. The cooling device 28 cools the clean air that flows down from above and covers the area around the vA device 72 .

According to the method for blowing clean air in a clean room according to the present invention configured as described above, the cooling device 28 is directly attached to the heat generating device 72 provided in the clean room 20, and the cooling device 28 is directly attached to the heat generating device 72 provided in the clean room 20.
2 prevents the clean air from being heated,
The air is maintained so that it always blows down within 0. In addition, the cooled air flows through the grating floor 20 to the underfloor chamber 26 to form a cooling layer A, and this cold air layer A is similar to the clean room 10 shown in FIG. It prevents it from rising.

〔Effect of the invention〕

As explained above, according to the method for blowing clean air in a clean room according to the present invention, a cold air layer is provided in the underfloor chamber, which prevents the upward flow of clean air and maintains a high degree of cleanliness in the clean room. I can do it.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a method for blowing clean air in a clean room according to the present invention, FIG. 2 is an explanatory diagram of a second embodiment of the method for blowing clean air in a clean room according to the present invention, and FIG. FIG. 7 is an explanatory diagram of a third example. 10.60.70...Clean room, 12...
・Ceiling chamber, 14...Air supply box, 1
6... Suction fan, 18... HEPA filter, 20... Clean room, 22... Grating end,
26... Underfloor chamber, 28... Cooling device,
32...II! Duct, 40m pipe,
42... Air conditioner, 48... Air supply pipe, 72
...Heat-generating equipment.

Claims (3)

[Claims] (1) An underfloor chamber is formed between the foundation floor and a permeable floor surface laid above the foundation floor, and clean air is blown out from the ceiling surface and inside the underfloor chamber through the permeable floor surface. A method for blowing clean air in a clean room, the method comprising forming a cold air layer in the underfloor chamber. (2) An underfloor chamber is formed between the foundation floor and a permeable floor surface laid above the foundation floor, and clean air is blown out from the ceiling surface and into the underfloor chamber through the permeable floor surface. A clean room clean air blowing method that involves blowing out cooled clean air from a part of the ceiling surface and forming an air curtain in the clean room with the cooled clean air. air blowing method. (3) An underfloor chamber is formed between the foundation floor and a permeable floor surface laid above the foundation floor, and clean air is blown out from the ceiling surface and into the underfloor chamber through the permeable floor surface. The method for blowing clean air into a clean room to be sucked in is characterized by covering the periphery of a heating element installed in the clean room with cooling air and supplying the cooling air into an underfloor chamber to form a cold air layer. How to blow clean air in a clean room.