Cleanroom Equipment and Air Circulation Units

Abstract

To provide a non-laminar flow type clean room apparatus capable of securing the cleanliness of an air conditioning region with a small number of ventilation while being a relatively simple facility.SOLUTION: A clean room apparatus comprises air circulation units 30 that are disposed in a clean room 10 and circulate air in the clean room 10. The air circulation unit 30 is provided with an intake opening 31 for sucking air in the clean room 10 at a position inside the clean room 10 and above an air conditioning region 11, and a plurality of air supply ports 32 that are disposed in the front face of the air circulation unit 30 and in distribution in a region up to a height facing the air conditioning region 11 and supply air laterally toward the air conditioning region 11. In the inside of the air circulation unit 30, there are provided a cooler 35, a high-performance filter 36, and a fan 37 that sucks air in the clean room 10 from the air intake opening 31, makes the air pass through the cooler 35 and the high-performance filter 36 and sends the air toward the air supply ports 32.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a clean room apparatus, and further to an air circulation unit that is suitably used in the clean room apparatus. [Background technology]

[0002] For example, clean room equipment is widely used in the field of semiconductor manufacturing. There are two types of clean room equipment: a non-laminar flow type (conventional type) in which air in the clean room is mixed and diluted by airflow, and a laminar flow type in which air in the clean room is pushed in one direction in a laminar flow state to exhaust dust. Of these, the non-laminar flow type clean room equipment has an advantage that it is more economical in terms of construction costs and operating costs than the laminar flow type clean room equipment. As an example of such a non-laminar flow type clean room equipment, as disclosed by the present applicant in Patent Document 1, a type is known that keeps the inside of the clean room clean by supplying clean air that is lower than the room temperature and filtered by a high-performance filter horizontally toward an air-conditioning area formed at the bottom of the clean room and diluting the air. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5361140 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional non-laminar flow cleanroom equipment is intended to uniformly mix and dilute the air in the entire cleanroom up to the ceiling. The ventilation rate required to satisfy the design values ​​for cleanliness and temperature uniformity is designed based on the amount of suspended particles (dust) generated in the cleanroom and the amount of heat generated in the room, but conventional non-laminar flow cleanroom equipment generally requires a relatively high ventilation rate, for example 20 times / h. The air conveying system accounts for a large proportion of the air conditioning energy in cleanroom equipment. For this reason, in order to reduce energy, it is effective to operate the equipment with an air conditioning volume that corresponds to the amount of suspended particles generated and the amount of heat generated in the room, and reduce the number of ventilation rates.

[0005] If the design value can be met with a small ventilation rate, there will be great benefits in terms of construction and operating costs, but in general, the area that requires air conditioning is from the floor to a limited height in the cleanroom, and yet with conventional non-laminar flow cleanroom equipment, the entire cleanroom up to the ceiling is mixed, making it impossible to significantly reduce the ventilation rate. For example, when designing the ventilation rate based on the amount of airborne particles generated, it cannot be lower than the ventilation rate assuming complete mixing, which is the theoretical value.

[0006] On the other hand, according to the clean room apparatus of the above-mentioned Patent Document 1, a swirling component is given to low-temperature clean air and it is supplied sideways to the air-conditioned area formed at the bottom of the clean room, so that the clean air is mixed with the air present in the air-conditioned area at the bottom of the clean room, and the dilution effect keeps the air-conditioned area clean. This non-laminar flow type clean room apparatus can ensure the cleanliness of the air-conditioned area with fewer ventilation cycles than conventional non-laminar flow type clean room apparatus. This allows for energy savings.

[0007] However, in either case, conventional clean room equipment is a large-scale system that requires the installation of a large outdoor air-conditioning unit that supplies air to the clean room and a return shaft that returns air from inside the clean room to the outdoor air-conditioning unit, and the overall installation distance of the ducts is long, requiring a long construction period.

[0008] An object of the present invention is to provide a non-laminar flow type clean room apparatus which can ensure the cleanliness of the air-conditioned area with a small number of ventilation cycles while using relatively simple equipment. [Means for solving the problem]

[0009] to this end, According to the present invention, A clean room apparatus in which an air-conditioning area is formed under a clean room partitioned by a ceiling, a floor, and a side wall, An outdoor air conditioning unit provided outside the clean room, which cools outdoor air to a low temperature using a cooler and converts it into purified air using a high-performance filter; an air circulation unit disposed on the floor within the clean room and circulating air within the clean room, the air circulation unit including an intake port for drawing in air within the clean room, the intake port being disposed within the clean room at a position above the air-conditioning area and on an upper surface of the air circulation unit, a plurality of intake ports on a front surface of the air circulation unit for supplying air laterally toward the air-conditioning area, a high-performance filter for cleaning the air circulating within the clean room, and a fan for drawing in air within the clean room through the intake port, passing the air through the high-performance filter, and blowing the air toward the intake port; An air intake port provided in the ceiling; an air supply duct provided outside the clean room and supplying low-temperature clean air from the outdoor air conditioner to the air supply port; Equipped with The outdoor air-conditioning unit includes an intake fan that passes the outdoor air through the cooler of the outdoor air-conditioning unit and the high-performance filter of the outdoor air-conditioning unit, and supplies the low-temperature clean air to the clean room through an intake port provided in the ceiling, The air supply duct is not directly connected to the air circulation unit, the air supply port provided in the ceiling is provided at a position for supplying air to a space within the clean room above the air intake port of the air circulation unit so that low-temperature clean air from the outdoor air-conditioning unit is sucked into the interior of the air circulation unit through the air intake port provided on the upper surface of the air circulation unit together with air accumulated above the air-conditioned area in the clean room; The low-temperature clean air from the outdoor air conditioner is supplied into the clean room through an air intake port provided in the ceiling, The clean air from the air circulation unit is supplied to an air-conditioned area in the clean room, and becomes an upward current due to the thermal influence of equipment present in the air-conditioned area in the clean room partitioned by the side walls, and is transported together with contaminants to a position above the air-conditioned area in the clean room. The clean air is circulated within the clean room equipment by sucking in air only from the air intake port of the air circulation unit without passing through the air supply duct. A clean room apparatus characterized by is provided.

[0010] In this clean room apparatus, The air circulation unit may be arranged along a side wall that defines the clean room. The air circulation unit further includes a cooler therein, the high-performance filter is disposed at a position between the cooler of the air circulation unit and the inside of the plurality of air intakes; The air that has been sucked into the air circulation unit from the air intake together with the low-temperature clean air from the outdoor air conditioner and that has accumulated above the air-conditioned area in the clean room may be cooled by the cooler of the air circulation unit, and may be converted into clean supply air by the high-performance filter of the air circulation unit and supplied to the air-conditioned area of ​​the clean room from a plurality of air intakes of the air circulation unit. It is also equipped with a local exhaust duct and an exhaust fan. The air within the clean room may be locally sucked in by the exhaust fan and exhausted to the outside through the local exhaust duct. The air circulation unit may be disposed along a side wall that defines the clean room so as to surround the equipment from the periphery.

[0011] Further, according to the present invention, An air circulation unit for circulating air in a clean room of a clean room apparatus, comprising: In the clean room apparatus, an air-conditioned area formed in a lower portion of the clean room partitioned by a ceiling, a floor, and side walls is kept clean, and contaminants are transported above the air-conditioned area in the clean room by an upward flow caused by the thermal influence of equipment present in the air-conditioned area, The clean room apparatus includes an external air conditioner provided outside the clean room, which cools external air to a low temperature using a cooler and converts it into purified air using a high-performance filter; the outdoor air-conditioning unit includes an air supply fan that passes the outdoor air through the cooler of the outdoor air-conditioning unit and the high-performance filter of the outdoor air-conditioning unit, and supplies the outside air as low-temperature clean air to the clean room through an air supply port provided in the ceiling; an air supply duct is provided for supplying the clean air to the clean room; and the clean air in the air supply duct is supplied to a position above the air-conditioned area in the clean room through an air supply port provided in the ceiling of the clean room; the air circulation unit is disposed on the floor of the clean room apparatus, and is provided with an intake port for drawing in air from within the clean room at a position inside the clean room and above the air-conditioning area, and a plurality of intake ports for supplying air laterally toward the air-conditioning area on a front surface of the air circulation unit, the intake port being provided on an upper surface of the air circulation unit, and is provided with a high-performance filter and a fan therein for drawing in air from within the clean room through the intake port, passing the air through the high-performance filter, and blowing the air toward the intake port, The air circulation unit is not directly connected to the air supply duct, and the low-temperature clean air from the outdoor air conditioner is supplied from an air supply port provided on the ceiling. The low-temperature clean air is sucked into the air circulation unit from the air intake port provided on the upper surface of the air circulation unit together with air that has accumulated above the air-conditioned area in the clean room, The clean air from the multiple air intake ports of the air circulation unit passes through the high-performance filter of the air circulation unit and is supplied to an air-conditioned area in the clean room, and becomes an upward current due to the thermal influence of equipment present in the air-conditioned area in the clean room partitioned by the side walls, and is transported together with contaminants to a position above the air-conditioned area in the clean room. The clean air is circulated within the clean room equipment by sucking in air only from the air intake port of the air circulation unit without passing through the air intake duct. An air circulation unit characterized by is provided.

[0012] In this air circulation unit, the plurality of air supply ports may be provided with fins that impart a swirling component to air supplied laterally toward the air-conditioned area. Effect of the Invention

[0013] According to the present invention, in a non-laminar flow type clean room apparatus that keeps the air-conditioned area formed at the bottom of the clean room clean, the cleanliness of the air-conditioned area can be ensured with an extremely small number of ventilations by circulating the air in the clean room with an air circulation unit. Also, by circulating the air in the clean room with an air circulation unit arranged in the clean room, it becomes possible to omit the installation of a return shaft for returning air to the outdoor air conditioner. As a result, a clean room apparatus that can ensure the cleanliness of the air-conditioned area with a small number of ventilations can be obtained, while being a simple facility that can be constructed in a relatively short construction period. Also, compared to a conventional non-laminar flow type clean room apparatus that uniformly mixes and dilutes the air in the entire clean room up to the ceiling, the cleanliness of the air-conditioned area can be ensured with a small number of ventilations, which enables energy savings. [Brief description of the drawings]

[0014] [Figure 1] 1 is a schematic configuration diagram for explaining a clean room apparatus according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a side view showing the internal structure of the air circulation unit. [Diagram 3] FIG. 2 is a front view of the air circulation unit as seen from inside the clean room. [Figure 4] This is a front view of an air intake port with fins attached so as to give a counterclockwise swirling component to the low-temperature air when viewed from inside the clean room. [Diagram 5]This is a front view of an air intake port with fins attached so as to give a clockwise swirling component to the low-temperature air when viewed from inside the clean room. [Figure 6] 1 is an explanatory diagram of air intake ports in which the swirling components of the low-temperature air blown out from adjacent air intake ports rotate in alternately opposite directions. FIG. [Figure 7] 1 is an explanatory diagram of air intake ports in which the swirling components of the cold air blown out from adjacent air intake ports are in the same rotation direction. FIG. [Figure 8] FIG. 13 is an explanatory diagram of an embodiment in which a plurality of air circulation units are arranged side by side and the number of operating air supply chambers is switched depending on the amount of air supplied. [Figure 9] 1 is a graph showing temperature distribution in a conventional non-laminar flow type clean room apparatus. [Figure 10] 1 is a graph showing the distribution of the number of suspended particles in a conventional non-laminar flow type clean room apparatus. [Figure 11] 4 is a graph showing the temperature distribution in the clean room apparatus of the present invention. [Figure 12] 1 is a graph showing the distribution of the number of suspended particles in the clean room apparatus of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] An example of an embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is an explanatory diagram of a clean room apparatus 1 according to an embodiment of the present invention. This clean room apparatus 1 is a non-laminar flow type (conventional type) that mixes and dilutes air in a clean room 10 by airflow. Note that in this specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals to avoid redundant description.

[0016] The inside of the clean room 10 is a closed space partitioned by a ceiling 10a, a floor (floor slab) 10b, and a side wall 10c. Such a clean room 10 is widely used, for example, in the field of semiconductor manufacturing. In the lower part of the clean room 10, an air-conditioned area 11 is formed, which is kept clean for manufacturing semiconductors. The air-conditioned area 11 is an area from the floor 10b to a predetermined height, and various equipment 12 such as semiconductor manufacturing equipment are present in the air-conditioned area 11. The height of the air-conditioned area 11 is higher than that of the equipment 12, and in this embodiment, the height of the equipment 12 is set to about 3.4 to 4 m, while the height of the equipment 12 is about 3 m. In the present invention, the air-conditioned area 11 is managed so that the cleanliness of suspended particles a in the air is equal to or lower than a predetermined concentration.

[0017] A local exhaust duct 13 that locally exhausts pollutants generated from the equipment 12 itself is connected to the equipment 12. An exhaust fan 14 is attached to the local exhaust duct 13 outside the clean room 10, and the exhaust fan 14 locally sucks in pollutants generated from the equipment 12 itself through the local exhaust duct 13 and discharges them to the outside as exhaust air EA.

[0018] An intake port 20 for clean air CA is provided in the ceiling 10a of the clean room 10. The intake port 20 for clean air CA is located directly above an air circulation unit 30, which will be described later. Low-temperature clean air CA produced by an outdoor air conditioner 21 is supplied to the intake port 20 through an intake duct 22. The outdoor air conditioner 21 is equipped with a coarse filter 23, a cooler 24, an intake fan 25, and a high-performance filter 26. Outside air OA is taken in upstream of the coarse filter 23, and the outside air OA passes through the coarse filter 23, the cooler 24, the intake fan 25, and the high-performance filter 26 in this order in the outdoor air conditioner 21 by the power of the intake fan 25. As a result, in the outdoor air conditioner 21, the outside air OA first passes through the coarse filter 23 and is preliminarily filtered, and then is cooled to a temperature lower than the room temperature by the cooler 24, and further, suspended particles are removed by the high-performance filter 26 to become clean air CA. The high-performance filter 26 is, for example, a HEPA filter, a ULPA filter, etc. The low-temperature clean air CA thus produced by processing in the outdoor air-conditioning unit 21 is supplied to the clean room 10 above the air-conditioned area 11 via the air supply duct 22 and the air supply port 20.

[0019] A plurality of air circulation units 30 that circulate air within the clean room 10 are disposed inside the clean room 10. Each air circulation unit 30 is disposed along the side wall 10c so as to surround the equipment 12 placed in the clean room 10 from the periphery.

[0020] The height of the air circulation unit 30 is higher than the height of the air-conditioned area 11. For example, while the height of the air-conditioned area 11 is about 3.4 to 4 m, the height of the air circulation unit 30 is set to about 5 m. Therefore, the lower part of the air circulation unit 30 is within the air-conditioned area 11, but the upper part of the air circulation unit 30 protrudes into the space above the air-conditioned area 11 in the clean room 10.

[0021] 2 and 3, an air intake port 31 for drawing in air from inside the clean room 10 is provided on the top surface of the air circulation unit 30. In addition, a plurality of air supply ports 32 are provided on the front surface of the air circulation unit 30 (the surface facing the inside of the clean room 10).

[0022] The air circulation unit 30 is equipped with a cooler 35, a high-performance filter 36, and a fan 37 that draws air from within the clean room 10 into the air circulation unit 30 through an intake port 31, passes the air through the cooler 35 and the high-performance filter 36, and then blows the air sideways into the clean room 10 through an intake port 32 provided on the front side of the air circulation unit 30. The high-performance filter 36 is, for example, a HEPA filter, a ULPA filter, or the like. This high-performance filter 36 is, for example, a low organic, low boron ULPA filter manufactured by Japan Cambridge Filter Co., Ltd., and has a pressure loss of 190 Pa or less at a rated air speed of 1.2 m / s.

[0023] As described above, the upper part of the air circulation unit 30 protrudes into the space above the air-conditioning area 11, so that the air above the air-conditioning area 11 in the clean room 10 is sucked into the air circulation unit 30 through the air intake 31 by the power of the fan 37.

[0024] Meanwhile, the multiple air intake ports 32 are disposed on the front surface of the air circulation unit 30, distributed over the entire area from the floor 10b of the clean room 10 to approximately the same height as the air-conditioned area 11. For this reason, the multiple air intake ports 32 blow air horizontally over the entire height of the air-conditioned area 11.

[0025] The cooler 35 and high-performance filter 36 provided inside the air circulation unit 30 are disposed in positions that cover the entire inside of the multiple air intake ports 32 provided on the front surface of the air circulation unit 30. Inside the air circulation unit 30, the high-performance filter 36 is located immediately inside the multiple air intake ports 32 (outside when viewed from the center of the clean room 10), and the cooler 35 is further disposed inside the high-performance filter 36 (outside when viewed from the center of the clean room 10).

[0026] Meanwhile, the fan 37 is disposed above the cooler 35 and the high-performance filter 36 inside the air circulation unit 30. A baffle plate 40 is provided between the fan 37 and the cooler 35 and the high-performance filter 36 to divide the internal space of the air circulation unit 30 into upper and lower parts. The baffle plate 40 has an opening 41 at a position corresponding to the inside of the cooler 35 (the outside when viewed from the center of the clean room 10), and at the position of the baffle plate 40, the internal space of the air circulation unit 30 communicates only at a position corresponding to the inside of the cooler 35 where the opening 41 is provided (the outside when viewed from the center of the clean room 10). The intake port 31 may be provided with an airflow adjustment mechanism (not shown) to adjust the inflow amount of air above the air-conditioned area sucked in by the fan 37.

[0027] For this reason, air drawn into the air circulation unit 30 from the air intake port 31 on the top surface of the air circulation unit 30 by the power of the fan 37 passes through the opening 41 at the position of the baffle plate 40, enters the space inside the cooler 35 (outside when viewed from the center of the clean room 10), passes through the cooler 35 and then the high-performance filter 36, and is blown sideways into the clean room 10 from the air supply port 32. The cooler 35 and the high-performance filter 36 are positioned in positions that cover the entire inside of the multiple air supply ports 32, so that air (supply air SA) that has passed through the cooler 35 and then the high-performance filter 36 is always blown out from the air supply port 32.

[0028] In addition, since the high-performance filter 36 has a high pressure loss, the air sent by the fan 37 has a uniform pressure inside the high-performance filter 36 (outside when viewed from the center of the clean room 10). Therefore, the air sucked by the fan 37 is uniformly cooled when passing through the coolers 35 provided over the entire vertical and horizontal areas of the multiple air supply ports 32 arranged vertically and horizontally, and passes through each air supply port 32 at approximately the same flow rate. In other words, since air passes through each air supply port 32 at a uniform temperature and uniform flow rate, there is no variation in the swirling component given by the fins 45 of each air supply port 32. As a result, clean air CA without variation in flow rate, temperature, and swirling component is blown out over the entire air-conditioning area 11, so there is no impact on the dilution and mixing effect of the entire air-conditioning area 11 by the non-laminar flow method. In this way, energy saving is achieved throughout the clean room 10. Furthermore, clean air CA with no variation in flow rate, temperature, or swirling components is blown out from each air intake 32 of the air circulation unit 30 throughout the entire air-conditioned area 11. This means that, compared to the conventional configuration in which clean air produced by an outdoor air-conditioning unit was supplied to the clean room via an air intake duct, the air intake duct can be omitted, the device can be simplified, and simple equipment can be provided that can be constructed in a relatively short construction period.

[0029] As shown in Figures 4 and 5, each air intake port 32 on the front side of the air circulation unit 30 is equipped with multiple fins 45 that impart a swirling component to the air that is supplied laterally toward the air-conditioned area 11 in the clean room 10.

[0030] The fins 45 are attached radially at appropriate equal intervals around the center of the air intake port 32, and in order to impart a swirling component to the air blown toward the clean room 10 (air-conditioned area 11), the fins 45 are arranged at an incline with respect to the central axis 32' of the air intake port 32. The inclination directions of the fins 45 are opposite in Fig. 4 and Fig. 5.

[0031] In this way, by attaching the inclined fins 45 radially to each air intake port 32, the air supplied laterally from the air intake port 32 toward the air-conditioned area 11 in the clean room 10 can be forced to flow along each fin 45 when passing through the air intake port 32. This gives a swirling component about the central axis 32' to the air blown out from the air intake port 32 toward the air-conditioned area 11 in the clean room 10.

[0032] 4 and 5, the inclination directions of the fins 45 are opposite, and with the fins 45 shown in Fig. 4, a counterclockwise swirling component is imparted to the air when it passes through the air intake port 32, when the front surface of the air circulation unit 30 is viewed from inside the clean room 10. On the other hand, with the fins 45 shown in Fig. 5, a clockwise swirling component is imparted to the air when it passes through the air intake port 32, when the front surface of the air circulation unit 30 is viewed from inside the clean room 10.

[0033] As described above, a plurality of air intake ports 32 are distributed over the entire front surface of the air circulation unit 30 in an area up to approximately the same height as the air-conditioned area 11. Therefore, the swirling components of the air blown out from adjacent air intake ports 32 cause interference between them.

[0034] For example, in the case of four intake ports 32a, 32b, 32c, and 32d arranged vertically as shown in Fig. 6, the swirling components of the air blown out from adjacent intake ports 32 have a relationship of mutually opposite rotational directions. That is, in the example shown in Fig. 6, the inclination direction of the fins 45 of the top intake port 32a and the third intake port 32c from the top is as described in Fig. 4, and air given a swirling component in the counterclockwise direction is blown out from these intake ports 32a and 32c. On the other hand, the inclination direction of the fins 45 of the second intake port 32b and the fourth intake port 32d from the top is as described in Fig. 5, and air given a swirling component in the clockwise direction is blown out from these intake ports 32b and 32d. In this way, air swirling in opposite rotational directions is blown out between adjacent air intake ports 32a and 32b, between air intake ports 32b and 32c, and between air intake ports 32c and 32d.

[0035] As in the example shown in Figure 6, if the swirling components of the air blown out from each air intake port 32a, 32b, 32c, and 32d are alternately made to rotate in opposite directions, air will be blown out in the same direction between air intake port 32a and air intake port 32b, between air intake port 32b and air intake port 32c, and between air intake port 32c and air intake port 32d, so that the swirling components of the air blown out from each air intake port 32a, 32b, 32c, and 32d can be made to mutually enhance each other.

[0036] On the other hand, as shown in the example of Fig. 7, when air swirling in the same rotational direction is blown out from the four air inlets 32a, 32b, 32c, and 32d arranged vertically (in the example shown in Fig. 7, air swirling in the counterclockwise direction), the air is blown out in directions that cancel each other out between the air inlets 32a and 32b, between the air inlets 32b and 32c, and between the air inlets 32c and 32d. In this way, if the swirling components of the air blown out from the air inlets 32a, 32b, 32c, and 32d are all in the same rotational direction, the swirling components of the air blown out from the air inlets 32a, 32b, 32c, and 32d can be made to cancel each other out.

[0037] Note that in Figures 6 and 7, the relationship between air intake ports 32 arranged vertically has been described; however, not only between air intake ports 32 arranged vertically, but also between air intake ports 32 arranged adjacent to each other horizontally or adjacent to each other diagonally, it is possible to appropriately set a relationship in which the swirling components of the air blown out from adjacent air intake ports 32 enhance each other's swirling components or a relationship in which the swirling components cancel each other out due to the swirling components of the air blown out from adjacent air intake ports 32.

[0038] In the clean room apparatus 1 configured as described above, low-temperature clean air CA produced by the outdoor air-conditioning unit 21 is supplied to the upper part of the clean room 10 through the air supply duct 22 and the air supply port 20. Since the air supply port 20 is located directly above the air circulation unit 30, the low-temperature clean air CA produced by the outdoor air-conditioning unit 21 is supplied to the space above the air-conditioned area 11, directly above the air circulation unit 30.

[0039] Then, air circulation is performed by the air circulation unit 30 inside the clean room 10. That is, by the power of the fan 37 provided in the air circulation unit 30, air above the air-conditioned area 11 in the clean room 10 is sucked into the air circulation unit 30 from the air intake port 31 together with the clean air CA supplied from the air intake port 20 to a position directly above the air circulation unit 30. Then, these airs (the air above the air-conditioned area 11 sucked into the air circulation unit 30 and the clean air CA) pass through the cooler 35 and the high-performance filter 36 inside the air circulation unit 30 to become low-temperature, clean supply air SA, and are blown sideways into the clean room 10 from the air intake port 32. In this case, the cooler 35 and the high-performance filter 36 are arranged at positions covering the entire inside of the multiple air intake ports 32, so that the low-temperature, clean supply air SA that has passed through the cooler 35 and the high-performance filter 36 in this order is always blown out from the air intake port 32.

[0040] In this way, the supply air SA blown out from each supply air port 32 is given a swirling component by the action of the fins 45, and the air in the air-conditioned area 11 at the bottom of the clean room 10 is attracted to the supply air SA, creating an attraction effect that causes the air to move together with the supply air SA. Accordingly, in accordance with the law of conservation of momentum, the speed of the supply air SA quickly decelerates after it is blown out from each supply air port 32.

[0041] In addition, when the intake air SA is supplied sideways into the clean room 10 from each air intake 32 on the front side of the air circulation unit 30 in this manner, the power of the fan 37 is controlled so that the intake air SA is blown out from each air intake 32 in a swirling manner toward the air-conditioned area 11 at the bottom of the clean room 10 at an average flow velocity at the discharge surface of 0.5 m / s or more and 1.2 m / s or less (preferably, 0.6 m / s or more and 1.1 m / s or less).

[0042] As a result, the low-temperature, clean supply air SA is mixed with the air present in the air-conditioned area 11, and the dilution effect reduces the concentration of suspended particles a throughout the air-conditioned area 11, making it possible to keep the air-conditioned area 11 clean. By blowing out the supply air SA from each supply air port 32 at a flow velocity of 0.5 m / s or more and 1.2 m / s or more, dilution mixing can be achieved throughout the air-conditioned area 11, which was not possible with displacement ventilation with a low supply air flow velocity, and suspended particles a that do not directly ride on the thermal upward current can also be removed. The supply air SA blown out from each supply air port 32 quickly decelerates, and furthermore, the supply air SA is supplied sideways toward the air-conditioned area 11, so that the supply air SA is not mixed with the air present above the air-conditioned area 11 in the clean room 10, and the clean, low-temperature supply air SA is mixed only with the air present in the air-conditioned area 11, making it possible to keep only the air-conditioned area 11 clean and at a low temperature.

[0043] Furthermore, contaminants generated from various devices 12 such as semiconductor manufacturing equipment placed in the clean room 10 are locally sucked in through the local exhaust duct 13 by the power of the exhaust fan 14, and are discharged to the outside as exhaust air EA. In this case, by setting the intake air volume of the intake air fan 25 provided in the outdoor air-conditioning unit 21 to be greater than the exhaust air volume of the exhaust fan 14, the inside of the clean room 10 can be constantly kept at a positive pressure, and the intrusion of contaminants from the outside can be prevented.

[0044] Furthermore, contaminants such as airborne particles a generated around the equipment 12, humans, etc. in the air-conditioned area 11 are heated by the thermal influence of the equipment 12, humans, etc., and gradually rise. Due to this upward flow, the contaminants such as airborne particles a generated in the air-conditioned area 11 are transported above the air-conditioned area 11 within the clean room 10.

[0045] Then, the air (heated air) that has accumulated above the air-conditioned area 11 in the clean room 10 is sucked into the air circulation unit 30 from the air intake 31 together with the clean air CA, and inside the air circulation unit 30, it passes through a cooler 35 and a high-performance filter 36 to become low-temperature, clean supply air SA, which is then blown sideways from the air intake 32 into the air-conditioned area 11 in the clean room 10. As a result, the air-conditioned area 11 is always maintained in a clean, low-temperature environment.

[0046] According to this clean room apparatus 1, by circulating the air in the clean room 10 with the air circulation unit 30, only the air-conditioned area 11 at the bottom of the clean room 10 can be kept clean by diluting and mixing, and compared to a conventional, general non-laminar flow type clean room apparatus in which the entire clean room up to the ceiling is diluted and mixed, the number of ventilation cycles (the number of ventilation cycles based on the entire volume of the clean room 10) can be made extremely small to ensure the cleanliness of the air-conditioned area 11. This makes it possible to reduce energy. In addition, by diluting and mixing the entire air-conditioned area 11 with the supply air SA due to the attraction effect of the swirling flow, the temperature difference between above and below inside the air-conditioned area 11 can be reduced.

[0047] Furthermore, by circulating the air in the clean room 10 with the air circulation unit 30 disposed in the clean room 10, it is possible to omit the installation of a return shaft for returning air to the outdoor air-conditioning unit 21. As a result, a clean room apparatus 1 can be obtained that is a simple facility that can be constructed in a relatively short construction period, yet can ensure the cleanliness of the air-conditioned area 11 with a small number of ventilations.

[0048] Although an example of a preferred embodiment of the present invention has been described above, the present invention is not limited to the illustrated embodiment. For example, the fins 45 may be formed by punching fins out of a flat plate, as in the swirl flow forming plate previously disclosed by the present applicant in FIG. 5 of JP-A-9-250803.

[0049] As shown in FIGS. 1 and 2, a machine room 50 may be formed under the floor 10b, and power may be supplied to the fan 37 of the air circulation unit 30 from a control device 51 disposed in the machine room 50 via a cable 52. A coolant may also be supplied to the cooler 35 from the control device 51 via a pipe 53. For example, the cable 52 for supplying power to the fan 37 of the air circulation unit 30 may be drawn from the floor 10 to the machine room 50 through the inside of the air circulation unit 30, thereby shortening the length of the cable 52 exposed to the inside of the clean room 10 and minimizing molecular contamination caused by the cable 52. A drain pan 55 may also be provided on the bottom surface of the air circulation unit 30, so that the drainage received by the drain pan 55 can be quickly collected in the machine room 50.

[0050] As described above, the supply air SA is supplied from the air inlet 32 ​​on the front side of the air circulation unit 30 toward the air-conditioning area 11 at the bottom of the clean room 10 at a flow rate of 0.5 m / s or more and 1.2 m / s or less, so that the entire air-conditioning area 11 can be mixed and diluted to keep it clean. In order to save energy, it is desirable to make the amount of supply air SA as small as possible within a range in which the cleanliness of the air-conditioning area 11 is at a desired level, depending on the heat generation load and the amount of suspended particles generated in the clean room 10. Therefore, it is desirable to provide an inverter or the like to the fan 37 provided inside the air circulation unit 30 to make the power of the fan 37 variable and change the overall ventilation frequency.

[0051] If the flow velocity of the supply air SA supplied to the air-conditioning area 11 becomes less than 0.5 m / s, the supply air SA will not be able to mix and dilute the entire air-conditioning area 11, and suspended particles will not be sufficiently removed from the air-conditioning area 11, which may result in a concern that a clean working environment will not be obtained. Therefore, as shown in Fig. 8, it is preferable to install multiple air circulation units 30 that supply the supply air SA to the air-conditioning area 11, and to configure the number of operating air circulation units 30 to be switched according to the supply air volume. For example, when reducing the supply volume of the supply air SA, the flow velocity of the supply air SA can be prevented from becoming less than 0.5 m / s by reducing the number of operating air circulation units 30.

[0052] 1 shows an example in which the air circulation unit 30 is installed on the side wall 1c, but in the case of a large clean room, the two air circulation units 30 may be arranged back-to-back between the side walls 1c and 1c1c of the clean room. In other words, the two air circulation units 30 may be arranged with their backs in close contact with each other so that their air intake ports 32 do not face each other. EXAMPLES

[0053] A conventional non-laminar flow type clean room device, which uniformly mixes and dilutes the air in the entire clean room up to the ceiling, and a clean room device of the present invention were both constructed, and actual measurements were taken of the temperature distribution and the distribution of the number of airborne particles. The clean room used was 4 m high, and the area up to a height of 2 m was the air-conditioned area. The temperatures and the number of airborne particles were the average values ​​of three locations. The number of airborne particles was measured as the number of particles 0.3 μm or larger (number / ft 3 In the conventional non-laminar flow type clean room equipment, the ventilation rate was set to 20 times / h. In the clean room equipment of the present invention, the ventilation rate was set to 12.7 times / h.

[0054] Figure 9 shows the temperature distribution in a conventional non-laminar flow type clean room equipment, and Figure 10 shows the distribution of the number of suspended particles in a conventional non-laminar flow type clean room equipment. Figure 11 shows the temperature distribution in the clean room equipment of the present invention, and Figure 12 shows the distribution of the number of suspended particles in the clean room equipment of the present invention. With regard to the air-conditioning area, the clean room equipment of the present invention had a temperature distribution equivalent to that of a conventional non-laminar flow type clean room equipment, despite having a low ventilation rate. In addition, the number of suspended particles was reduced more than that of the conventional non-laminar flow type clean room equipment. [Industrial Applicability]

[0055] The present invention is widely applicable to clean room apparatuses used in various industrial fields. [Explanation of symbols]

[0056] OA Outdoor air SA Air Supply EA Exhaust CA Clean Air 1. Clean room equipment 10. Clean Room 11 Air conditioning area 12 Equipment 13 Local exhaust duct 14 Exhaust fan 20 Air intake (clean air CA) 21 External conditioning machine 22 Air supply duct 23 Coarse Filter 24 Cooler 25 Intake fan 26 High-performance filters 30 Air Circulation Unit 31 Air Intake 32 Air supply port 35 Cooler 36 High Performance Filter 37 Fans 40 Baffle Plate 41 Opening 41 45 Finn 50 Machine room 51 Control Equipment 52 Cable 53 Piping 55 Drain Pan

Claims

1. A clean room apparatus in which an air-conditioning area is formed in a lower part of a clean room partitioned by a ceiling, a floor, and side walls, An outdoor air conditioning unit provided outside the clean room, which cools outdoor air to a low temperature using a cooler and converts it into purified air using a high-performance filter; an air circulation unit disposed on the floor within the clean room and circulating air within the clean room, the air circulation unit including an intake port for drawing in air within the clean room, the intake port being disposed within the clean room at a position above the air-conditioning area and on an upper surface of the air circulation unit, a plurality of intake ports on a front surface of the air circulation unit for supplying air laterally toward the air-conditioning area, a high-performance filter for cleaning the air circulating within the clean room, and a fan for drawing in air within the clean room through the intake port, passing the air through the high-performance filter, and blowing the air toward the intake port; An air intake port provided in the ceiling; an air supply duct provided outside the clean room and supplying low-temperature clean air from the outdoor air conditioner to the air supply port; Equipped with The outdoor air-conditioning unit includes an intake fan that passes the outdoor air through the cooler of the outdoor air-conditioning unit and the high-performance filter of the outdoor air-conditioning unit, and supplies the low-temperature clean air to the clean room through an intake port provided in the ceiling, The air supply duct is not directly connected to the air circulation unit, the air supply port provided in the ceiling is provided at a position for supplying air to a space within the clean room above the air intake port of the air circulation unit so that low-temperature clean air from the outdoor air-conditioning unit is sucked into the interior of the air circulation unit through the air intake port provided on the upper surface of the air circulation unit together with air accumulated above the air-conditioned area in the clean room; The low-temperature clean air from the outdoor air conditioner is supplied into the clean room through an air intake port provided in the ceiling, The clean air from the air circulation unit is supplied to an air-conditioned area in the clean room, and becomes an upward current due to the thermal influence of equipment present in the air-conditioned area in the clean room partitioned by the side walls, and is transported together with contaminants to a position above the air-conditioned area in the clean room. The clean air is circulated within the clean room equipment by sucking in air only from the air intake port of the air circulation unit without passing through the air supply duct. A clean room apparatus comprising:

2. The air circulation unit is arranged along a side wall that partitions the clean room.

2. The clean room apparatus according to claim 1 .

3. The air circulation unit further includes a cooler therein, the high-performance filter is disposed at a position between the cooler of the air circulation unit and the inside of the plurality of air intakes; The air that has accumulated above the air-conditioned area in the clean room and that has been drawn into the air circulation unit from the air intake together with the low-temperature clean air from the outdoor air conditioner is cooled by the cooler of the air circulation unit, and is made into clean supply air by the high-performance filter of the air circulation unit and is supplied to the air-conditioned area of ​​the clean room from the multiple air intakes of the air circulation unit.

3. The clean room apparatus according to claim 1 or 2.

4. Further comprising a local exhaust duct and an exhaust fan, The air in the clean room is locally sucked by the exhaust fan, and the air in the clean room is exhausted to the outside through the local exhaust duct. The clean room apparatus according to any one of claims 1 to 3.

5. The air circulation unit is arranged so as to surround the equipment along the side walls that define the clean room. The clean room apparatus according to any one of claims 1 to 4.

6. The plurality of air intakes are provided with fins that impart a swirling component to the air supplied laterally toward the air-conditioning area. The clean room apparatus according to any one of claims 1 to 5.

7. An air circulation unit for circulating air in a clean room of a clean room apparatus, comprising: In the clean room apparatus, an air-conditioned area formed in a lower portion of the clean room partitioned by a ceiling, a floor, and side walls is kept clean, and contaminants are transported above the air-conditioned area in the clean room by an upward flow caused by the thermal influence of equipment present in the air-conditioned area, The clean room apparatus includes an external air conditioner provided outside the clean room, which cools external air to a low temperature using a cooler and converts it into purified air using a high-performance filter; the outdoor air-conditioning unit includes an air supply fan that passes the outdoor air through the cooler of the outdoor air-conditioning unit and the high-performance filter of the outdoor air-conditioning unit, and supplies the outside air as low-temperature clean air to the clean room through an air supply port provided in the ceiling; an air supply duct is provided for supplying the clean air to the clean room; and the clean air in the air supply duct is supplied to a position above the air-conditioned area in the clean room through an air supply port provided in the ceiling of the clean room; the air circulation unit is disposed on the floor of the clean room apparatus, and is provided with an intake port for drawing in air from within the clean room at a position inside the clean room and above the air-conditioning area, and a plurality of intake ports for supplying air laterally toward the air-conditioning area on a front surface of the air circulation unit, the intake port being provided on an upper surface of the air circulation unit, and is provided with a high-performance filter and a fan therein for drawing in air from within the clean room through the intake port, passing the air through the high-performance filter, and blowing the air toward the intake port, The air circulation unit is not directly connected to the air supply duct, and the low-temperature clean air from the outdoor air conditioner is supplied from an air supply port provided on the ceiling. The low-temperature clean air is sucked into the air circulation unit from the air intake port provided on the upper surface of the air circulation unit together with air that has accumulated above the air-conditioned area in the clean room, The clean air from the multiple air intake ports of the air circulation unit passes through the high-performance filter of the air circulation unit and is supplied to an air-conditioned area in the clean room, and becomes an upward current due to the thermal influence of equipment present in the air-conditioned area in the clean room partitioned by the side walls, and is transported together with contaminants to a position above the air-conditioned area in the clean room. The clean air is circulated within the clean room equipment by sucking in air only from the air intake port of the air circulation unit without passing through the air intake duct. An air circulation unit.

8. The plurality of air intakes are provided with fins that impart a swirling component to the air supplied laterally toward the air-conditioned area.

8. An air circulation unit according to claim 7.

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