JP2008224146A - Non-unidirectional airflow type clean room device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-unidirectional airflow type clean room device ensuring cleanliness of a work area with the small number of times of return air and reducing the temperature difference of the work area. <P>SOLUTION: The non-unidirectional airflow type clean room device 1 keeping the inside of a clean room 10 clean by supplying clean air SA into the clean room 10 and diluting it has air supply ports 15 for horizontally supplying the clean air SA filtered by a high efficiency filter 33 and lower in temperature than an indoor temperature, toward the work area 11, and exhaust ports 16 for exhausting air in the clean room 10 above the work area 11. The clean air SA is supplied from the air supply ports 15 so that the average flow velocity at a discharge surface into the room is ≥0.5 m/s and ≤1.2 m/s. This clean room device 1 can dilute and keep clean only the work area 11 formed at the lower part of the clean room 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a non-laminar flow type clean room apparatus.

  For example, clean room devices are widely used in the field of semiconductor manufacturing. There are two types of clean room systems: a non-laminar flow method (conventional method) that mixes and dilutes the air in the clean room with an air flow, and a laminar flow method that exhausts dust while pushing the air in the clean room in a laminar state in one direction is there. Among these, the non-laminar type clean room apparatus has an advantage that it is more economical in terms of construction cost, operation cost, etc. than the laminar type clean room apparatus. As such a non-laminar flow type clean room device, for example, as disclosed by the present applicant, it is common to uniformly mix and dilute the air in the entire clean room (see Patent Document 1).

On the other hand, a replacement ventilation system is known in which supply of air is suppressed in the lower part of the room while suppressing attraction of about 0.2 m / s, and return air is returned from the ceiling surface or the wall surface of the room at a high position (Patent Document 2). 3). The air conditioning target area of this replacement ventilation system is a living area from the floor to about 2 m in height, and is an air conditioning system that can be expected to reduce the number of ventilations compared to the mixed system.
Japanese Examined Patent Publication No. 2-48770 JP 2002-372268 A Japanese Patent Laid-Open No. 2005-282892

As described above, the conventional non-laminar flow type clean room apparatus is intended to uniformly mix and dilute the air in the entire clean room up to the ceiling. The required ventilation frequency that satisfies the design values of cleanliness and temperature uniformity is designed based on the amount of suspended particles (dust) generated in the clean room and the amount of heat generated in the room. According to JIS, ISO class 6 (particles of 0.5 μm or more) 1000 / ft ³ or less) at 30 to 90 times / h, ISO class 8 (a 0.5μm or more particles 100,000 / ft ³ or less) at the required 10 to 20 times / h and many ventilation rate And The air conveyance system accounts for a large proportion of the air conditioning energy of the clean room device. For this reason, in order to reduce energy, it is effective to operate with an air-conditioning air volume according to the amount of suspended particles generated and the amount of heat generated in the room, and reduce the number of ventilations.

  If the design value can be satisfied with a small number of ventilations, a great merit can be gained in terms of construction cost and operation cost. In general, the work area is about 2 meters above the floor in the clean room, but the conventional non-layered In the flow type clean room device, the entire clean room up to the ceiling is mixed, so the number of ventilations cannot be greatly reduced. For example, when the ventilation frequency is designed from the amount of airborne particles generated, it cannot be lower than the theoretical ventilation frequency assuming perfect mixing. Also, when designing the ventilation frequency from the calorific value in the clean room, the conventional non-laminar flow type clean room device that uniformly mixes and dilutes the air in the clean room has a supply / exhaust temperature difference of 8 ° C to 10 ° C. Cannot be designed with increasing ventilation frequency.

  On the other hand, the replacement ventilation system has a feature of the indoor flow field that the heat rising flow generated from the heating element and the blown air flowing along the floor surface actively flow, and the air flow is small in other places. If the source of suspended particles is a heating element, and the suspended particles are transported to the upper part of the living area by the rising heat generated from the heating element, the living area can be kept extremely clean, rather than the mixing method. Cleanliness can be maintained with a small number of ventilations. However, if the source of suspended particles does not generate heat, or if the heat rise is small and the suspended particles cannot be transported to the upper part of the living area, the suspended particles cannot be diluted because of the low air flow. There is. In addition, in the replacement ventilation system, the temperature difference between the lower part of the living area and the upper part of the living area is likely to occur, and in order to keep the temperature deviation of the living area below the set value, the operation can be performed with a larger difference between the supply and exhaust temperatures than the mixed system. There wasn't.

  An object of the present invention is to provide a non-laminar flow type clean room apparatus capable of ensuring the cleanliness of a work area with a small number of ventilations and reducing the work area temperature difference.

  According to the present invention, a clean room device of a non-laminar flow system that keeps the inside of a clean room clean by supplying clean air to the clean room and diluting it, the clean air having a temperature lower than the room temperature filtered by the high-performance filter The air supply port for supplying air horizontally toward the work area formed in the lower part of the clean room, and the exhaust port for exhausting the air inside the clean room above the work area. Provided is a clean room device characterized in that air is supplied at an average flow velocity at a discharge surface into the room of 0.5 m / s or more and 1.2 m / s or less.

  In the clean room apparatus of the present invention, only the work area formed in the lower part of the clean room can be diluted and kept clean. You may provide the said air supply opening with the fin which gives a turning component with respect to clean air. Further, the air inside the clean room exhausted from the exhaust port may be configured to return to the clean room from the air supply port. The high-performance filter is an air filtration filter having a colorimetric method of 99 or more, more preferably DOP 0.3 μm 99.97 or more, and still more preferably DOP 0.1 μm 99.999 or more. In order to supply clean air from the supply port toward the work area below the clean room, a high performance filter is provided in one of the supply passages. In this case, the air supply path is, for example, the air supply path from the outside air intake port to the air supply port after the air conditioning process is performed in the case of the all outside air method. In the case of the method of taking care, at least one of the outside air intake port and the return air port, for example, the confluence point of the outside air and the return air is set as one end. The air supply path extends from the intake air mixed with the return air to the air supply port after the air conditioning process is performed.

  According to the present invention, in a non-laminar flow type clean room device that mixes and dilutes air in a clean room with an air flow, the cleanliness of the work area can be ensured with a smaller number of ventilations than in the past. For this reason, energy reduction becomes possible.

  Hereinafter, embodiments of the present invention will be described 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. The clean room apparatus 1 is a non-laminar flow method (conventional method) in which air in the clean room 10 is mixed and diluted by an air flow. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  The interior of the clean room 10 is a closed space defined by a ceiling 10a, a floor 10b, and a side wall 10c. Such a clean room 10 is widely used, for example, in the field of semiconductor manufacturing. A work area 11 for manufacturing semiconductors and the like is formed in the lower part of the clean room 10. The work area 11 is an area from the floor to a height of about 2 m, and a person 12 is present in the work area 11 to perform various operations. In the present invention, the airborne particles a in the work area 11 are managed so as to have a cleanliness level equal to or lower than a predetermined concentration.

  A plurality of air supply ports 15 are provided in the lower portion of the clean room 10, and a plurality of exhaust ports 16 are provided in the upper portion of the clean room 10. The air supply port 15 is disposed at the height of the work area 11 (up to a height of about 2 m from the floor), and the exhaust port 16 is disposed above the work area 11. In the illustrated example, an air supply port 15 is opened at the lower part of the side wall 10c of the clean room 10, and an exhaust port 16 is opened at the ceiling 10a.

  An air supply chamber 20 is provided on the lower back side of the side wall 10 c of the clean room 10. The height of the air supply chamber 20 is substantially equal to the height of the work area 11 formed in the clean room 10. The front surface 21 of the air supply chamber 20 is exposed at the lower portion of the side wall 10 c of the clean room 10. In other words, the side wall 10 c and the front surface 21 (supply surface) of the supply chamber 20 are substantially on the same plane, and the supply chamber 20 itself is disposed outside the clean room 10. Note that the front surface 21 (supply surface) of the supply chamber 20 does not necessarily have to be on the same plane as the side wall 10c.

  The interior of the air supply chamber 20 exposed in the lower part of the side wall 10c of the clean room 10 is thus hollow, and a plurality of air supply ports 15 are arranged vertically and horizontally on the front surface 21 as shown in FIG. . In the air supply chamber 20, clean air (supply air) SA adjusted to a low temperature with a supply / exhaust temperature difference created by processing the outside air OA and the return air RA by the air conditioner 22, for example, 10 ° C. or more, It is supplied via the air supply duct 23. As a result, the clean air SA is supplied laterally from the plurality of air supply ports 15 formed in the front surface 21 of the air supply chamber 20 toward the work area 11 below the clean room 10. In this case, in order to stir the air in the entire work area 11, the clean air SA has an average flow rate of 0.5 m / s or more and 1.2 m / s or less (for example, 0.9 m / s or less) from the air supply port 15. Is supplied toward the work area 11. In addition, the reference position of the clean air SA having a flow velocity of 0.5 m / s or more and 1.2 m / s or less is immediately after exiting the air supply port 15, that is, immediately after passing through the fin 40 described later. It is the room side of the front surface 21 (air supply surface) of the air supply chamber 20. The average flow velocity of the clean air SA on the indoor side of the front surface 21 (air supply surface) of the air supply chamber 20 is a value obtained by dividing the amount of blown air by the area of the blowout face (total area of the air supply port 15).

  Among the plurality of exhaust ports 16 arranged on the ceiling 10 a of the clean room 10, some of the exhaust ports 16 communicate with the air conditioner 22 through the return air duct 25, and the other exhaust ports 16 pass through the exhaust duct 26. It communicates with the outside. Thereby, a part of the air exhausted from the clean room 10 through the plurality of exhaust ports 16 is returned to the air conditioner 22 through the return air duct 25 as return air RA, and the remaining air is exhausted from the exhaust EA. It is to be discharged to the outside.

  The air conditioner 22 includes a coarse filter 30, a cooler 31, a blower 32, and a high performance filter 33. The outside air duct 34 for taking in outside air OA and the above-described return air duct 25 are connected to the upstream side of the coarse filter 30, and the outside air OA and the return air RA are coarsely circulated in the air conditioner 22 by the power of the blower 32. The filter 30, the cooler 31, the blower 32, and the high-performance filter 33 are passed in this order. As a result, in the air conditioner 22, the outside air OA and the return air RA first pass through the coarse filter 30 to preliminarily remove suspended particles, and then are cooled to a temperature lower than the room temperature by the cooler 31. Airborne particles are removed by the performance filter 33 to obtain clean air SA. The high performance filter 33 is composed of, for example, a HEPA filter, a ULPA filter, or the like.

  The low-temperature clean air (supply air) SA produced by processing in the air conditioner 22 in this way is supplied to the work area 11 below the clean room 10 via the supply air duct 23 and the supply air chamber 20. In this case, the power of the blower 32 is such that the average flow velocity at the discharge surface is 0.5 m / s or more from each air supply port 15 on the front surface 21 of the air supply chamber 20 toward the work area 11 below the clean room 10. The clean air SA is controlled to be supplied at a flow rate of 2 m / s or less (for example, 0.9 m / s or less).

  Each of the air supply openings 15 on the front surface 21 of the air supply chamber 20 is an opening provided in plural on the front surface 21 of the plate-like body. The front surface 21 is a face portion of the air supply unit, and the air supply port 15 may be formed as an opening such as a punching or a slit. The entire front surface 21 is a filter surface, and the entire amount of air supply is from the entire front surface 21. You may blow out. As shown in FIGS. 3 and 4, a plurality of fins 40 are respectively mounted behind the front surface 21 (the back side of the air supply chamber 20). A support member 41 is provided in the center of each air supply port 15, and the fins 40 are radially attached around the support member 41 at appropriate equal intervals. In order to give a swirling component to the clean air SA blown from the air supply port 15 toward the clean room 10 (working area 11), the fins 40 are respectively inclined with respect to the central axis 15 'of the air supply port 15. 3 and 4, the inclination directions of the fins 40 are opposite to each other.

  In this way, the fins 40 that are inclined to the air supply ports 15 are attached radially, so that the clean air SA that has flowed from the inside of the air supply chamber 20 toward the air supply port 15 passes through the air supply ports 15. When making it flow, it can be forced to flow along each fin 40. Thus, a swirl component centered on the central axis 15 ′ is given to the clean air SA blown out from the air supply port 15 toward the work area 11 below the clean room 10.

  Here, in FIGS. 3 and 4, the inclination directions of the fins 40 are opposite to each other. According to the fins 40 shown in FIG. 3, the front surface 21 of the air supply chamber 20 is moved when passing through the air supply port 15. When viewed from the indoor side of the clean room 10 (work area 11), a swirl component in the counterclockwise direction is given to the clean air SA. On the other hand, depending on the fin 40 shown in FIG. 4, when the front surface 21 of the air supply chamber 20 is viewed from the indoor side of the clean room 10 (work area 11) when passing through the air supply port 15, A swirl component is given to the clean air SA.

  As described above, a plurality of air supply ports 15 are arranged vertically and horizontally on the front surface (lower portion of the side wall 10c of the clean room 10) 21 of the air supply chamber 20, but the clean air blown out from the adjacent air supply ports 15 is clean. The swirl components of the air SA are in a relationship of mutually opposite rotation directions. That is, for example, as shown in FIG. 5, four air supply ports 15a, 15b, 15c, and 15d arranged in the vertical direction will be described as an example. The first air supply port 15a and the third air supply port from the top. In 15c, the inclination direction of the fin 40 is in the state described with reference to FIG. 3, and clean air SA given a swirl component in the counterclockwise rotation direction is blown out from the air supply port 15a and the air supply port 15c. On the other hand, in the second air supply port 15b and the fourth air supply port 15d from the top, the inclination direction of the fin 40 is the state described in FIG. 4, and the air supply port 15b and the air supply port 15d Clean air SA given a swirl component in the rotational direction is blown out. In this way, clean air that swirls in opposite rotation directions between the adjacent air supply port 15a and the air supply port 15b, between the air supply port 15b and the air supply port 15c, and between the air supply port 15c and the air supply port 15d, respectively. SA is blown out.

  That is, as shown in FIG. 6, clean air SA that swirls in the same rotational direction from the four air supply ports 15a, 15b, 15c, and 15d arranged in the vertical direction (in the example shown in FIG. 6, all are counterclockwise). When the clean air SA that swirls in the rotation direction is blown out, between the air supply port 15a and the air supply port 15b, between the air supply port 15b and the air supply port 15c, and between the air supply port 15b and the air supply port 15c. The clean air SA is blown out in a direction that cancels each other. If it does so, the swirl component of the clean air SA which blows off from each air supply opening 15a, 15b, 15c, 15d will be canceled.

  On the other hand, as described with reference to FIG. 5, if the swirl components of the clean air SA blown from the air supply ports 15a, 15b, 15c, and 15d are alternately reversed, the air supply ports 15a and 15b Since the clean air SA is blown out in the same direction between the air supply port 15b and the air supply port 15c and between the air supply port 15b and the air supply port 15c, each air supply port The swirling components of the clean air SA blown out from 15a, 15b, 15c, and 15d are not cancelled, and the swirling motions are promoted with each other.

  In FIG. 5, the relationship between the upper and lower air supply ports 15 has been described. However, as described above with reference to FIG. 2, a plurality of air supply ports 15 are vertically and horizontally arranged on the front surface 21 of the air supply chamber 20. They are arranged side by side. Accordingly, as shown in FIG. 7, the clean air SA blown out from the adjacent air supply ports 15 not only between the relationship between the air supply ports 15 arranged vertically but also between the air supply ports 15 arranged horizontally. Inclination directions of the fins 40 provided in the air supply ports 15 are set so that the swirl components of the airflow components have a relationship of rotation directions opposite to each other.

  Now, in the clean room apparatus 1 configured as described above, the low-temperature clean air SA produced by the air conditioner 22 is supplied to the lower part of the clean room 10 through the air supply duct 23 and the air supply chamber 20 by the operation of the air supply fan 32. Supply sideways toward the work area 11. In this case, by the power control of the blower 32, the average flow velocity at the discharge surface from each air supply port 15 toward the work area 11 below the clean room 10 is 0.5 m / s or more and 1.2 m / s or less. Then, clean air SA is supplied. Specifically, when passing through the air supply port 15, the swirl component is given to the clean air SA by the action of the fins 40. The flow velocity here is, for example, 1.8 m / s, and when it is discharged from the air supply port 15 of the front surface 21, the pressure is increased to a low speed of 0.9 m / s. In other words, when the blown air volume is divided by the area of the front surface 21, a flow velocity of 0.9 m / s was obtained in this example. Of course, when the air is supplied directly into the room from the fin 40 with the configuration shown in FIG. 8 described later, the blower 32 and a damper (not shown) are provided so that an average flow velocity of 0.5 to 1.2 m / s is obtained at that position. Adjust. In this way, the clean air SA is supplied sideways at a flow velocity of 0.5 m / s or more and 1.2 m / s or less while turning from each supply port 15 toward the work area 11 below the clean room 10.

  Thereby, the clean air SA is mixed with the air existing in the work area 11, and the concentration of the suspended particles a in the entire work area 11 is lowered by the dilution effect, so that the work area 11 can be kept clean. . In this case, the amount of attraction in the vicinity of the air supply unit 20 is proportional to the square of the blowout face surface speed. By supplying clean air SA from each air supply port 15 at a flow rate of 0.5 m / s or more and 1.2 m / s or less, dilution and mixing of the entire work area 11 that could not be performed by replacement ventilation with a low air supply flow rate It is possible to remove suspended particles a that are not directly on the heat rising flow. Then, the air supply from the air supply unit 20 is decelerated at a position at the same distance as the height of the air supply surface (for example, when the height of the front surface 21 is 2.1 m, a point 2.1 m from the front surface 21 to the indoor side). Thus, the wind speed is substantially the same as that of the replacement ventilation, and here, the wind speed is 0.3 m / s. Further, since the clean air SA is supplied sideways toward the work area 11, the clean air SA is not mixed with the air existing above the work area 11 in the clean room 10. The clean air SA is mixed with only the air existing in the work area 11 so that only the work area 11 can be kept clean.

  Further, since the clean air SA blown out from each air supply port 15 is given a swirling component by the action of the fins 40 and is blown out, the air in the work area 11 below the clean room 10 is attracted to the clean air SA and moves together. Attraction works. Along with this, the speed of the clean air SA is promptly decelerated after blowing out from each air supply port 15 according to the law of conservation of momentum.

  On the other hand, the work area 11 in the clean room 10 includes a person 11 or the like as a heating element. Therefore, the clean that is supplied into the work area 11 and is in thermal contact with the person 11 or other heat-generating devices. The air SA is heated and gradually rises. Due to the upward flow, contaminants such as suspended particles a generated around the person 11 in the work area 11 can be transported above the work area 11 in the clean room 10.

  In the clean room 10, air accumulated above the work area 11 (heated air) is discharged to the outside of the clean room 10 through the exhaust port 16. In this way, while supplying clean air SA to the work area 11 at a flow rate of 0.5 m / s or more and 1.2 m / s or less in the lateral direction, contaminants such as suspended particles a and the like from the upper part of the clean room 10 together with heated air. By exhausting the air, the inside of the clean room 10 is ventilated, and the work area 11 is kept in a clean environment.

  According to this clean room apparatus 1, as compared with the conventional general non-laminar flow type clean room apparatus in which the entire clean room up to the ceiling is diluted and mixed, only the work area 11 below the clean room 10 is diluted and mixed and cleaned. By maintaining, the number of ventilations (the number of ventilations based on the volume of the entire clean room 10) can be made smaller than before, and the cleanliness of the work area 11 can be ensured. For this reason, energy reduction becomes possible.

  In addition, the air in the vicinity of the air supply unit 20 can be attracted by three times or more as compared with the case of the simple circular opening by the attracting action of the swirl flow. By increasing the amount of attraction in the vicinity of the air supply unit 20, the air flow velocity toward the downstream side is quickly reduced, the heat rising flow generated in the work area 11 is prevented from being disturbed, and the suspended particles advection to the work area 11 And the advection of the heat generation load can be suppressed. By diluting and mixing the entire work area 11 with clean air SA, the temperature difference between the upper and lower sides can be reduced within the work area 11. On the other hand, since the air is not mixed above the work area 11 in the clean room 10, the vertical temperature difference is relatively large.

  Here, the graph line 45 in FIG. 1 shows the temperature change in the height direction in the clean room 10, and shows a state where the temperature is higher toward the right in FIG. 1. As indicated by the graph line 45, since the vertical temperature difference is small in the work area 11, the temperature change is small in the height direction, and the vertical temperature difference is small above the work area 11, so that the height direction is small. The temperature change increases. According to this clean room apparatus 1, as shown by the graph line 45, the temperature change in the height direction at the upper part of the work area 11 becomes larger. Therefore, the clean air SA supplied into the clean room 10 and the clean room 10 An operation in which the temperature difference (supply / exhaust temperature difference) of the air discharged from the engine is, for example, 10 ° C. or more is also possible.

  As mentioned above, although an example of preferable embodiment of this invention was demonstrated, this invention is not limited to the form of illustration. For example, the exhaust port 16 may be formed in the side wall 10 c in the upper part of the clean room 10.

  3 and 4, the example in which the blowing members having a configuration in which the plurality of fins 40 are radially attached to the support member 41 is mounted on each air supply port 15 has been described. However, the present invention is not limited to this configuration. For example, the air flow stabilizer formed by punching a fin from a flat plate such as the swirl flow forming plate previously disclosed by the applicant of the present invention in FIG. This end face may be exposed to the indoor side with a configuration to which is added. In this case, it is necessary to set the blown air amount at the air supply port 15 to 0.5 to 1.2 m / s. Further, among the plurality of air supply ports 15 arranged vertically and horizontally on the front surface 21 of the air supply chamber 20, the clean air SA blown out from the adjacent air supply ports 15 between the air supply ports 15 arranged vertically. However, the swirl components of the clean air SA blown out from the adjacent air supply ports 15 have the same rotation between the air supply ports 15 arranged side by side. It may be set to have a directional relationship. Conversely, between the air supply ports 15 arranged side by side, the swirl components of the clean air SA blown out from the adjacent air supply ports 15 are in the opposite rotational directions, but are arranged vertically. Further, between the air supply ports 15, the swirl components of the clean air SA blown from the adjacent air supply ports 15 may be set to have the same rotational direction. Further, the swirl components of the clean air SA blown from all the air supply ports 15 may be set so that all have the same rotational direction. Further, the swirl component of the clean air SA blown out from each air supply port 15 may be set so as to be irregularly the same rotation direction or the reverse rotation direction. The rotation direction of the swirl component of the clean air SA blown from each air supply port 15 can be arbitrarily set.

  Further, as shown in FIG. 8, a cylinder 42 may be attached around a plurality of guide fins 40 attached to each air supply port 15. Thus, in the air supply port 15, the outer periphery of the plurality of guide fins 40 is surrounded by the inner wall surface 43 of the cylinder 42 (cylindrical inner wall surface 43 centering on the central axis 15 ′ of the air supply port 15). Thus, the swirl component in the clockwise direction or the counterclockwise direction can be more forcibly given to the clean air SA. In this case, the length L of the cylinder 42 in the direction along the central axis 15 ′ of the air supply port 15 is more than half of the width l of the guide fin 40 in the direction along the central axis 15 ′ of the air supply port 15. It is good to set. This may be exposed indoors (for example, the end surface in contact with the front surface 21 is exposed) and installed without providing a face portion such as a filter or punching. However, the wind speed of the air supply to the room immediately after passing through the fin 40 needs to be suppressed to 0.5 to 1.2 m / s.

  The high-performance filter 33 may be provided in the air conditioner 22 as shown in FIG. 1, but may be provided in the air supply duct 23 or the air supply chamber 20. When provided in the air supply unit 20, the air flow rate of the high-performance filter 33 is slowed to suppress pressure loss, and the amount of air flowing into the high-performance filter 33 is made uniform. Instead of providing the high-performance filter 33 in the perpendicular direction, as shown in FIG. 9, the high-performance filter 33 may be provided obliquely so that the flow path cross-sectional area of the filter inflow portion decreases toward the downstream side.

  The air supply chamber 20 may be provided outside the side wall 10c of the clean room 10 as shown in FIG. 1, but the air supply chamber 20 may be provided inside the clean room 10 as shown in FIG. When the air supply chamber 20 is provided inside the clean room 10, the air supply chamber 20 may be covered with a wall or the like so that dust does not accumulate. That is, a wall body is built on the indoor side at a distance from the side wall 10c of the clean room 10, and the air supply chamber 20, the air supply duct 23, and dampers are accommodated in the double wall formed thereby. Further, the air supply duct 23 having no outer flange is guided into the clean room 10, and a blowout face provided with a turning guide vane (fin 40) is attached to the indoor facing surface at a height of 2 m or less from the floor of the air supply duct 23. Also good. In other words, the inner flange-type rectangular gutter duct may be lowered from the upper part of the clean room 10 to the floor, and the entire indoor side surface corresponding to the work area 11 may be configured as an open surface or a ventilation surface.

  As described above, the clean room apparatus 1 has clean air SA at a flow rate of 0.5 m / s or more and 1.2 m / s or less from the air supply port 15 on the front surface of the air supply chamber 20 toward the work area 11 below the clean room 10. Is characterized in that the entire work area 11 is mixed and diluted to keep it clean. However, in order to save energy, the supply amount of clean air SA should be made as small as possible within a range where the cleanliness of the work area 11 becomes a desired level according to the heat generation load in the clean room 10 and the amount of suspended particles generated. Is desirable. Therefore, it is desirable to provide a configuration in which an inverter or the like is provided in the blower 32 so that the power of the blower 32 can be varied, and the overall ventilation frequency can be changed.

  However, if the flow rate of the clean air SA supplied toward the work area 11 is less than 0.5 m / s, the entire work area 11 cannot be mixed and diluted by the clean air SA, and suspended particles are removed from the work area. There is a concern that it will not be able to be removed sufficiently from 11, and a clean working environment will not be obtained. If the flow rate of the clean air SA is less than 0.5 m / s, the amount of induced air in the vicinity of the air supply chamber 20 decreases, and the phenomenon approximates the indoor flow field of the conventional replacement ventilation system. The variation in the number and the temperature variation in the work area 11 are increased.

  Therefore, as shown in FIG. 11, a plurality of air supply chambers 20 for supplying the clean air SA toward the work area 11 are installed, and the number of the air supply chambers 20 for supplying the clean air SA from the air supply duct 23 is determined. It is good to comprise so that it may switch according to an air supply amount. In the illustrated example, clean air SA is supplied as it is from the air supply duct 23 to the first air supply chamber 20 among the four air supply chambers 20, but the second to fourth air supply chambers 20. On the other hand, an open / close damper 46 is provided in the middle of the air supply duct 23 so that the air supply to the second to fourth air supply chambers 20 can be controlled. As the open / close damper 46, a variable damper (VD) or a motor damper (MD) can be used. When changing the number of ventilations by changing the heat generation load in the clean room 10 or the amount of suspended particles generated, the air supply chamber supplies the clean air SA by changing the air flow rate of the blower 32 by an inverter and opening and closing the open / close damper 46 appropriately. The number of 20 is changed. For example, in order to reduce the air flow rate of the blower 32, the flow rate of the clean air SA is 0.5 m by closing a part or all of the open / close damper 46 and reducing the number of the supply chambers 20 supplying the clean air SA. / S can be prevented.

A clean room apparatus of the present invention was constructed using an actual clean room, and the distribution of the number of suspended particles and the actual temperature distribution were measured. The clean room used has a specification of ISO class 8 (100,000 particles / ft ³ or less of 0.5 μm or more). The size of the clean room and the measurement points are shown in FIG. Four swirl flow induction type air supply chambers having a height of 2 m were provided on one side wall of a clean room having a depth of 19 m. In order to change the attracting amount of the air supply chamber alone, the blowing air speed was changed to four cases by changing the ventilation frequency and the number of blowing operation. Measure the number of suspended particles (particle size 0.5 μm to 5 μm) and temperature by height at the three measurement positions in the center of the clean room (A), far from the blowout (B), and blowout (C). Three hour average values were compared. The indoor sensible heat load and the amount of dust generated from the supply / exhaust temperature difference and the number of floating particles in the supply / exhaust are shown in FIGS. 13 (a) and 13 (b).

  In FIG. 14, the temperature in the height direction and the number of dust particles for each operating wind speed were compared. From FIG. 14, it can be confirmed that the number of suspended particles on the floor 1 m, which is the representative height of the work area, is suppressed as compared with the number of suspended particles on the floor 3 m, which is the non-working area. This is because suspended particles generated from the equipment in the clean room and the human body (wearing dust-free clothing) were pushed up to the non-working area. However, it can be confirmed that the slower the operating wind speed and the smaller the amount of blow-out attraction, the greater the variation in the number of suspended particles on the floor, and the greater the temperature variation in the work area.

  The present invention can be widely applied to clean room apparatuses used in various industrial fields.

It is a schematic block diagram for demonstrating the clean room apparatus concerning embodiment of this invention. It is a front view of an air supply chamber. It is a front view of the air supply port which attached the fin so that the turning component of a counterclockwise rotation direction seeing from a work area side might be given to low temperature air. It is a front view of the air supply opening | mouth which attached the fin so that the turning component of a clockwise rotation direction might be given to low temperature air seeing from the work area side. It is explanatory drawing of the air supply port which made the swirl component of the low temperature air blown off from an adjacent air supply port alternately the reverse rotation direction. It is explanatory drawing of the air supply port which made the rotation component of the low temperature air blown off from an adjacent air supply port the same rotation direction. The swirl components of the low-temperature air blown out from the adjacent air supply ports are in the relationship of opposite rotation directions between the air supply ports arranged vertically and the air supply ports arranged horizontally. It is explanatory drawing of the air supply opening set to. It is a longitudinal cross-sectional view of the air supply port which attached the cylinder around the guide fin. It is a longitudinal cross-sectional view of the air supply chamber which provided the high performance filter diagonally so that the flow-path cross-sectional area of a filter inflow part may become small downstream. It is explanatory drawing of embodiment which provided the air supply chamber in the inside of a clean room. It is explanatory drawing of embodiment comprised so that the operating number of an air supply chamber might be switched according to an air supply amount. It is explanatory drawing of the measurement point in the clean room in an Example. It is a graph which shows the indoor sensible heat load amount (a) and dust generation amount (b) which were calculated | required from the supply / exhaust temperature difference and the number of floating particles of supply / exhaust. It is the graph which compared the temperature of the height direction according to driving | running | working wind speed, and the number of dust particles.

Explanation of symbols

OA outside air RA return air SA clean air 1 clean room device 10 clean room 11 work area 15 air inlet 16 exhaust port 20 air supply chamber 22 air conditioner 23 air supply duct 25 return air duct 26 exhaust duct 33 high performance filter 40 fin

Claims (3)

It is a non-laminar flow type clean room device that keeps the inside of the clean room clean by supplying clean air to the clean room and diluting it,
An air supply port that supplies clean air filtered by a high-performance filter laterally toward the work area formed in the lower part of the clean room, and air inside the clean room is exhausted above the work area. And an exhaust port to
A clean room device, wherein clean air is supplied from the air supply port at an average flow velocity of 0.5 m / s to 1.2 m / s on the discharge surface into the room.   2. The clean room apparatus according to claim 1, wherein a fin that gives a swirl component to clean air is provided at the air supply port.   The clean room apparatus according to claim 1 or 2, wherein air inside the clean room exhausted from the exhaust port is returned to the clean room from the air supply port.

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