Clean room air conditioning system

Abstract

To provide an air conditioning system of a clean room, capable of suitably realizing a clean room in saved space at a low cost.SOLUTION: An air conditioning system of a clean room includes: an object space S having a device 5 installed therein; an adjustment part 8 for forming a space at an upper level than the device 5; a fan filter unit 2 for sending air downward; a suction port 8b disposed on an upper face 8a of the adjustment part 8 and communicating the internal space of the adjustment part 8 and the object space S; and a dry coil incorporated in the adjustment part 8. The flow of air A1 sent out from the fan filter unit 2 to a floor 13 is guided to a target direction orthogonal to an alignment direction of the fan filter unit 2 along the floor 13.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an air conditioning system for a clean room, and more particularly to an air conditioning system for an industrial clean room that is easily applicable to buildings with low floor heights. [Background technology]

[0002] Figure 12 shows an example of an air conditioning system in a clean room. The target space S is configured as a ballroom-style industrial clean room, and multiple fan filter units 2 are installed on the ceiling 1. The fan filter unit 2 draws air above the ceiling 1 into a housing using a fan and blows it onto a filter covering the entire lower surface of the housing, and sends the purified air that passes through the filter to the target space S below as indoor air A1.

[0003] The floor 3 of the target space S is constructed as a raised floor made of materials such as punching panels, gratings, etc. The air sent from the fan filter unit 2 to the target space S as indoor air A1 passes through the openings in the floor 3 and escapes to the space under the floor as return air A2, is sent to the space above the ceiling through the return shaft 4 that connects the space under the floor with the ceiling, and is again supplied to the target space S from the fan filter unit 2 as indoor air A1.

[0004] In the target space S, which is an industrial clean room, equipment (device) 5 such as production equipment is in operation, and the indoor air A1 receives exhaust heat from the equipment 5 and is heated before being released under the floor as return air A2. The heated return air A2 needs to be cooled to a temperature suitable for the operation of the equipment 5 before returning from under the floor to the ceiling space and being sent out again from the fan filter unit 2. In the example shown here, a cooling unit 6, which is a dry coil, is provided near the entrance of the return air shaft 4 to cool the return air A2 after it has passed through the floor 3 of the target space S.

[0005] 12, clean air is supplied to the target space S from the fan filter unit 2, while air is circulated throughout the entire facility including the target space S. In this type of air circulation, the fan filter units 2 send air generally downward into the target space S, but the fan filter units 2 are sparsely installed on the ceiling 1, and the airflow formed thereby is not a unidirectional push-out flow, but a non-unidirectional airflow that dilutes and mixes dust generated in the room with the clean air.

[0006] It should be noted that the example shown here is a schematic diagram, and in an actual industrial clean room, in addition to what is shown in the diagram, further equipment such as an outdoor air conditioner and a humidifier with a fan in the circulation path are usually provided, but these are not shown here.

[0007] Prior art documents that are examples of old tunnel-type clean rooms related to this type of clean room air conditioning system include, for example, the following Patent Document 1. Tunnel-type clean rooms have a higher level of cleanliness than ballroom-type clean rooms, but are similar in structure, so they are shown here as an example. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 62-194140 Summary of the Invention [Problem to be solved by the invention]

[0009] Incidentally, in the conventional ballroom-type clean rooms as described above, a return shaft space partitioned off from the target space S is necessary around the target space S for air circulation or to ensure an airway to the dry coils, etc. Also, in order to blow the air lifted by the return shaft down by the fans of the fan filter units 2, a space with a certain degree of planar area and height must be provided above the ceiling 1 on which the numerous fan filter units 2 are installed (behind the ceiling) to ensure an air flow to the fan filter units 2 and to make it possible to secure space for a catwalk for maintenance of the fan filter units 2.

[0010] Furthermore, in order to sparsely install the fan filter units 2 as described above in the target space S and widely supply a non-unidirectional airflow, it is necessary to construct the wide-area ceiling 1 as a cell ceiling, that is, a system ceiling, which is optimal for placing filters, as the installation surface for the fan filter units 2. Ultimately, whether the fan filter units 2 are installed sparsely or in part of a panel ceiling, installation costs will increase because they are placed at fixed intervals, so it is common to install cells over the entire surface and then cover it with blank panels.

[0011] Furthermore, in the case of an industrial clean room, a balancer damper (not shown) is installed in the passageway of the target space S or in the boundary partition between the room and the target space S, and an outdoor air conditioner (not shown) supplies air to the target space S so that the pressure is slightly positive with respect to atmospheric pressure, thereby forming a positive pressure equal to the resistance of the balancer damper. Air circulated by the fan suction of the fan filter unit 2 flows from the target space S with this slight positive pressure, and negative pressure is generated in the ceiling space where the fan suction position is due to pressure loss in each part of the air passage, as the fan filter unit 2 operates. This creates a negative pressure difference between the space in the ceiling and the outside, which is atmospheric pressure. For this reason, a pressure-resistant mechanism using costly sealing or sturdy panels is required on the building structure side to prevent dust from entering the space in the ceiling space from the outside. In this way, the installation of a wide ceiling and a space in the ceiling space was a factor in increasing the cost of constructing the target space S as a clean room.

[0012] Additionally, there was a need for a solution to cases where it was difficult to install large-area cell ceilings or panel ceilings in the first place due to spatial constraints, such as low ceilings in the target buildings, which is where the desired effect of this project would be achieved.

[0013] In view of the above-described situation, the present invention aims to provide an air conditioning system for a clean room that reduces the area required for the installation surface of a fan filter unit and can maintain a sufficient level of cleanliness in the target space while allowing the other areas of the target space to be covered by a vertical ceiling. [Means for solving the problem]

[0014] The present invention includes a target space in which a device that needs to maintain its own temperature within a predetermined range while applying a thermal load to the surrounding air is installed, an adjustment unit that is provided above a floor, partitioned from the target space, and forms a space at a level above the device, a fan filter unit that is provided on the underside of the adjustment unit and sends air downward toward the floor, an intake port that is provided on the upper surface of the adjustment unit and connects the internal space of the adjustment unit to the target space, and a dry coil that is built into the adjustment unit to regulate the temperature of the air circulated from the intake port by operation of the fan filter unit, and the main stream of air sent out from the fan filter unit toward the floor collides with the floor and then flows along the surface of the floor due to the Coanda effect. While forming thermal stratification The flow is guided along the floor in a desired direction perpendicular to the arrangement direction of the fan filter units. The air is guided in a desired direction to a region where the device is arranged, which is away from the fan filter unit in a plan view, and the air flow is prevented from disturbing the air in the entire room of the target space. The present invention relates to an air conditioning system for a clean room, characterized in that the air conditioning system is configured as follows. In the clean room air conditioning system of the present invention, the system can be configured to draw in return air through an intake port provided on the upper surface of the adjustment unit toward the other side, and to blow out supply air downward from a fan filter unit provided on the lower surface of the adjustment unit toward one side. In the clean room air conditioning system of the present invention, the fan filter unit and the wall of the target space can be positioned so that at least a portion of the main flow of air sent out from the fan filter unit flows downward along the wall of the target space, and then flows further along the wall and floor of the target space.

[0015] The clean room air conditioning system of the present invention can be configured so that the air flow that is sent out from the fan filter unit toward the floor and guided along the floor is guided in a desired direction by being blocked in its horizontal direction by an air flow sent out from another fan filter unit or by a wall.

[0016] In the air conditioning system for a clean room of the present invention, the adjustment section can be configured as a box-shaped structure including the fan filter unit and the suction port.

[0017] In the air conditioning system for a clean room of the present invention, the adjustment section can be configured as a duct-like structure extending horizontally and with a plurality of the fan filter units arranged along the longitudinal direction.

[0018] In the air conditioning system for a clean room of the present invention, a hanging wall extending downward from the vicinity of the air outlet of the fan filter unit can be provided on the lower surface of the adjustment section. Effect of the Invention

[0019] According to the air conditioning system for a clean room of the present invention, it is possible to reduce the area required for the installation surface of the fan filter unit while maintaining a sufficient degree of cleanliness in the target space. [Brief description of the drawings]

[0020] [Figure 1] 1 is a schematic elevational view showing an example (first embodiment) of an air conditioning system for a clean room according to the present invention; [Diagram 2] 2 is a schematic cross-sectional plan view of the air conditioning system of FIG. 1, taken along the line II-II of FIG. [Diagram 3] FIG. 4 is a perspective view showing an example of a configuration of an adjustment unit. [Figure 4] FIG. 11 is a schematic cross-sectional plan view showing another example of the configuration of the adjustment portion. [Diagram 5]FIG. 4 is a schematic elevational view showing another example (second embodiment) of an air conditioning system for a clean room according to the present invention. [Figure 6] 6 is a schematic plan view of the air conditioning system of FIG. 5, taken along line VI-VI of FIG. 5. [Figure 7] FIG. 11 is a schematic elevational view showing still another example (third embodiment) of the configuration of the air conditioning system for a clean room according to the present invention. [Figure 8] 8 is a schematic plan view of the air conditioning system of FIG. 7, taken along line VIII-VIII of FIG. 7. [Figure 9] FIG. 1 shows the results of simulating the air conditions in a clean room air conditioning system according to the present invention, where (A) shows the air temperature distributed in a cross section of the space along the position of the equipment, and (B) shows the air temperature distributed in a cross section of the space along the position between the equipment. [Figure 10] 1A and 1B show the results of simulating particle concentration in the air in a clean room air conditioning system according to an embodiment of the present invention, where (A) shows the particle concentration distribution in the air in a cross section of space along the position of the equipment, and (B) shows the particle concentration distribution in the air in a cross section of space along the position between the equipment. [Figure 11] FIG. 1 shows the results of simulating the air condition in an air conditioning system of a clean room by implementing the present invention, where (A) shows the age of air distributed in a cross section of the space along the position of the equipment, and (B) shows the age of air distributed in a cross section of the space along the position between the equipment. [Figure 12] FIG. 1 is a schematic elevational view showing an example of a conventional air conditioning system for a clean room. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0022] 1 and 2 show an example (first embodiment) of an air conditioning system for a clean room according to the present invention, and in the figures, parts denoted by the same reference numerals as in FIG. 12 represent the same things.

[0023] In this first embodiment, an adjustment unit 8 equipped with a fan filter unit 2 is installed in a wall area of ​​the target space S. The adjustment unit 8 forms a space partitioned from the target space S inside, sucks in air in the upper part of the target space S as return air A2, adjusts the temperature by indirect heat exchange with a cooling medium such as cold water in the dry coil, and sends out clean indoor air A1 from the fan filter unit 2. In other words, the adjustment unit 8 is functionally roughly equivalent to the space combined with the ceiling and the dry coil in the conventional example shown in FIG. 11. The adjustment unit 8 sucks in the air that rises in temperature in the upper part of the target space S as return air A2, but in terms of the relationship of hanging from the building frame itself and the vertical ceiling that is panel finished, it is economically preferable that the top end of the adjustment unit is hung lower than the vertical ceiling 10 of the target space S. The adjustment unit 8 draws in the heated and rising air at the top of the target space S as return air A2, but since the side of the suspended adjustment unit 8 is close to the vertical ceiling 10, the intake port 8b of the adjustment unit 8 is also close to the vertical ceiling 10, which is preferable.

[0024] In this first embodiment, the adjustment unit 8 is a box-shaped structure provided above the floor 13 at a level above the equipment (device) 5, and two rows are provided, one row on each side of the walls 7, 7 that form the two opposing sides of the target space S in a plan view. An intake port 8b for drawing in air is provided on the top surface 8a of the box-shaped adjustment unit 8. The intake port 8b opens into the target space S, and here the internal space of the adjustment unit 8 is directly connected to the target space S.

[0025] A fan filter unit 2 is disposed on the lower surface 8c of the adjustment unit 8. The fan filter unit 2 is a device called a fan filter unit (FFU) or the like that has a fan and a HEPA filter in a housing, and the air in the adjustment unit 8 is sucked into the housing by the fan and blown onto a filter that covers the entire lower part of the housing, and the purified air is sent downward as indoor air A1 to the target space S below. In JP 2019-090547 A, which is an example of the applicant's own conventional invention, the ceiling 1 configured as a dropped ceiling is used as the installation surface of the fan filter unit 2, but in this first embodiment, the lower surface 8c of the adjustment unit 8 is configured as the installation surface of the fan filter unit 2, and the area of ​​the installation surface of the fan filter unit 2 is limited to the area near the wall.

[0026] In a plan view of the adjustment section 8, the fan filter unit 2 on the lower surface 8c is provided at a position close to one side of the adjustment section 8, while the suction port 8b on the upper surface 8a is provided at a position close to the other side of the adjustment section 8. A cooling unit 6, which is a dry coil, is provided within the adjustment section 8 to separate the suction port 8b and the fan filter unit 2, and the air sucked in from the suction port 8b is cooled by passing through the dry coil before being sent out from the fan filter unit 2.

[0027] A hanging wall 9 is provided on the lower surface 8c of the box-shaped adjustment section 8 so as to extend downward from the periphery of the fan filter unit 2, and adjusts the direction of the air blown out from the fan filter unit 2 as described later. Thus, in this first embodiment, each adjustment section 8 may be configured as a unit having one fan filter unit 2 and one cooling unit 6 per box-shaped structure, and further having an inlet 8b. Furthermore, since the planar dimensions of the HEPA filter are economically limited, each adjustment section 8 may be configured as a unit having multiple fan filter units 2, one cooling unit 6, and an inlet 8b per box-shaped structure depending on the air volume. Multiple fan filter units 2 may be arranged in parallel in the same direction to form a single mass.

[0028] In this specification, expressions such as "downward" and "sideways" are used in relation to air flow, etc., but these do not only refer to directions that exactly match the vertical or horizontal directions, but also refer to directions that can be generally considered to be "downward" or "sideways" in the normal sense, or in an air conditioning system such as the present invention. Furthermore, an expression such as "along the floor" does not only refer to a direction that exactly matches the surface of the floor, but also means that the direction is generally along the surface of the floor. Similarly, expressions such as "perpendicular" and "horizontal" do not only mean that one direction and another direction form a right angle or that the direction is exactly horizontal to the direction of gravity, but refer to an angle that can be practically expressed as "perpendicular" or "horizontal".

[0029] The adjustment unit 8 is installed at an appropriate height above the equipment 5 in the target space S, for example, by hanging it from the ceiling 10. The ceiling 10 may be a vertical ceiling structure below the slab of the upper floor or roof, and dustproof measures such as dustproof paint may be applied to this, or it may be configured as a panel ceiling and the concrete pouring surface may be hidden to provide dustproof measures. In particular, in steel-framed buildings, the underside of the floor may be made of steel plates. In this case, dustproof measures such as gap treatment may be applied to the underside of the floor of the upper floor, and the ceiling 10 may be configured as a vertical ceiling. In this way, the cost of interior materials for the ceiling 10 can be reduced.

[0030] The following describes how to set the area in which the adjustment units 8 are provided, and how to arrange the fan filter units 2. In this first embodiment, as shown in Fig. 2, the adjustment units 8 are provided in two rows along the walls 7 at both ends of a room that is generally rectangular in plan view. The fan filter units 2 are provided on the undersides 8c of the adjustment units 8, so that the target space S as a whole is provided with two rows of fan filter units 2 in a line, one row on each side along the two opposing walls.

[0031] As described above, the adjustment unit 8 has the fan filter unit 2 on one side in plan view and the suction port 8b on the opposite side (other side), but the adjustment unit 8 is arranged relative to the wall 7 so that the side where the suction port 8b is provided is close to the wall 7, and the fan filter unit 2 is located on the opposite side of the wall 7 across the fan filter unit 2 in plan view. When viewed from the fan filter unit 2, the wall 7 is located on one side in a direction perpendicular to the direction in which the multiple fan filter units 2 are arranged in plan view, and the suction port 8b is located in front of it. By arranging in this way, a flow with little pressure loss can be formed as air transport by arranging the suction port 8b, the built-in dry coil, and the fan filter unit 2. Furthermore, the suction port 8b can be located on the wall side opposite to the air flow that flows toward the center of the room roughly downward of the fan filter unit 2 that forms the air flow toward the floor 13 side, which is a desirable shape for preventing the occurrence of a short circuit.

[0032] The configuration of the adjustment unit 8 shown here is merely an example, and the form of the adjustment unit 8 and the types and forms of the equipment devices provided in the adjustment unit 8 are not limited to this. For example, although the dry coil is illustrated as being disposed inside the adjustment unit 8, it may be disposed at the suction port 8b. Also, if necessary, a humidifier (not shown) may be provided to adjust the humidity.

[0033] 2 and 3 show an example in which the adjustment unit 8 is configured as a unit individually equipped with the fan filter unit 2, the suction port 8b, and the dry coil, but it is also possible to configure it such that multiple fan filter units 2 are arranged along the longitudinal direction on the underside 8c of the adjustment unit 8 that extends like a duct along the horizontal direction, as shown in Fig. 4. Installing the adjustment unit 8 so that the fan filter units 2 are arranged in a direction perpendicular to the desired direction is sufficient for guiding the air, as described below.

[0034] Unlike the floor 3 in the above-mentioned conventional example shown in Fig. 12, the floor 13 of the target space is not designed as a raised floor that allows air to circulate underneath the floor 13. On the upper surface of the floor 13, equipment 5 such as production equipment is placed and operates. The equipment 5 is, for example, production equipment that processes objects such as base material wafers that form semiconductor integrated circuits, substrates for flat panel displays, or containers that store these items. These equipment 5 are devices that need to give a large amount of heat generated by themselves to the surrounding air, while maintaining the temperature within a predetermined range in the areas that handle their own semi-finished products, etc.

[0035] As shown in Fig. 1, clean air is sent from the fan filter unit 2 downward toward the floor 13 of the target space S as indoor air A1. The downward indoor air A1 collides with the floor 13 and changes its flow direction along the surface of the floor 13. In the case of the first embodiment, the wall 7 is located in one of the four horizontal directions for the indoor air A1 sent out from the fan filter unit 2, and the downward flow of the indoor air A1 sent out from another adjacent fan filter unit 2 exists in the other two directions. Most of the indoor air A1 sent out downward from the fan filter unit 2 and changed its direction along the floor 13 is blocked by these in three directions and guided in the remaining one direction, which is the desired direction (Note that, with regard to the indoor air A1 sent out from the fan filter units 2 located at both ends of a plurality of fan filter units 2 arranged in a line, the walls 7 are located in two directions and there is a flow of the indoor air A1 sent out from the adjacent fan filter unit 2 in one direction, so that the indoor air A1 similarly flows in the remaining one direction). The downward indoor air A1 collides with the floor 13, and a flow is formed along the surface of the floor 13 and its direction is determined. If there are no obstacles such as equipment 5 in the direction of the flow, the air flow along the floor surface will flow without peeling off the floor surface due to the Coanda effect. Here, the "target direction" is the direction of the area to which it is desired to supply the indoor air A1 as viewed from the fan filter unit 2, and in the case of a clean room such as the first embodiment, it is the direction of the area in which the equipment 5 is located. In terms of the drawing, it is the right for the fan filter units 2 arranged in the left row in the drawing, and the left for the fan filter units 2 arranged in the right row.

[0036] The indoor air A1, which has been redirected in this way, moves toward the center of the target space S in which the equipment 5 is placed. At this time, the main stream of the indoor air A1 does not peel off the floor surface between the equipment 5 due to the Coanda effect, but crawls along the upper surface of the floor 13, receiving the exhaust heat from the equipment 5. As a result, some of the indoor air A1, which has risen in temperature, receives more exhaust heat by slowing its crawling speed, particularly after colliding with the equipment 5, and moves upward due to the density difference caused by the temperature difference. In this way, the air currents crawling along the floor surface due to the Coanda effect and the air currents heated by collisions with the equipment 5 are not disturbed by the slow air current speed throughout the room, and a temperature stratification is formed on the floor 13 where the higher the position, the higher the temperature, and the lower the position, the lower the temperature.

[0037] In this first embodiment, the adjustment unit 8 and the fan filter unit 2 are provided along the walls 7 on both sides of the room in a plan view, and the above-mentioned air movement occurs for each of the fan filter units 2 on both sides. The flow of the indoor air A1 along the floor 13 flows from positions along the walls 7 on both sides of the target space S to the opposite side of the walls 7, so that when viewed from the floor 13, flows of the indoor air A1 are formed from both ends of the target space S toward the center.

[0038] The main streams of indoor air A1 flowing along the floor 13 from both ends of the target space S travel along the floor 13 while absorbing exhaust heat from the equipment 5, then collide with each other at the center of the floor 13 and begin to rise. An intake port 8b of the adjustment unit 8 is provided above the floor 13, and a portion of the indoor air A1 above the floor 13 is taken into the adjustment unit 8 from the intake port 8b as return air A2. At this time, the return air A2 is cooled to an appropriate temperature by a dry coil provided in the adjustment unit 8, and is then supplied to the target space S from the fan filter unit 2 as indoor air A1.

[0039] In addition, another part of the main flow of the indoor air A1 that is blown out from each of the adjustment units 8 along the walls 7 on both sides and flows along the floor 13 collides with each other on the floor 13 in the center, where the dynamic pressure of each air flow is reacquired as static pressure and then changed direction, causing the air to start rising. This change in direction allows the rising air current to rise without disturbing the stratified air conditioning layer. An intake port 8b of the adjustment unit 8 is provided above the floor 13, and some of the heated indoor air above the floor 13 is taken into the adjustment unit 8 from the intake port 8b as return air A2. At this time, the return air A2 is cooled to an appropriate temperature by the dry coil 6 provided in the adjustment unit 8, and is then supplied to the target space S from the fan filter unit 2 as indoor air A1.

[0040] Another part of the indoor air A1 discharged downward from the fan filter unit 2 rises without moving very far along the floor 13 due to collision with the floor 13 or receiving exhaust heat from the equipment 5, and is sucked in through the intake port 8b of the adjustment section 8. Here, as described above, the hanging wall 9 is provided around the fan filter unit 2 on the lower surface 8c of the adjustment section 8. If the hanging wall 9 was not provided, part of the indoor air A1 discharged from the fan filter unit 2 would be attracted to this air flow, causing a short circuit in which the air is again taken into the adjustment section 8 shortly after being discharged from the fan filter unit 2. Such a short circuit is a wasteful movement from the viewpoint of supplying air in an appropriate state to the target area (in this case, the area around the equipment 5), and is energy inefficient.

[0041] Therefore, if the hanging wall 9 is provided near the air outlet of the fan filter unit 2, the air flow sent downward from the fan filter unit 2 is prevented from mixing with the air flow ascending through the area near the adjustment unit 8 in a plan view, thereby preventing the occurrence of a short circuit. Here, the hanging wall 9 is attached so as to surround the periphery of the air outlet of the fan filter unit 2, but the hanging wall 9 does not necessarily have to be provided so as to surround the entire periphery of the air outlet of the fan filter unit 2, and can be appropriately changed according to the surrounding conditions of the fan filter unit 2, etc. For example, when the adjustment unit 8 is disposed close to a wall, the hanging wall 9 on the wall side may be omitted, or when the fan filter units 2 of the adjustment unit 8 are adjacent to each other at a close distance, the hanging wall 9 between the adjacent fan filter units 2 may be omitted. In these cases, it is considered that the occurrence of a short circuit can be prevented even without the hanging wall due to the presence of a wall or the air blown from the adjacent fan filter units 2.

[0042] In this manner, in the air conditioning system of the first embodiment, as shown in FIG. 1, the indoor air A1 sent downward from the fan filter unit 2 installed at the end of the target space S flows along the upper surface of the floor 13, and when it reaches the center, it collides with each other and rises, and is sucked in through the intake port 8b and returns to the adjustment section 8 as return air A2, and the return air A2 that has returned to the adjustment section 8 is sent downward again from the fan filter unit 2 as indoor air A1, forming an air circulation. In addition, in such air circulation, a part of the indoor air A1 flowing along the upper surface of the floor 13 receives exhaust heat from the equipment 5 on the way before reaching the center, and is heated, its density decreases, and it rises, and it joins above the floor 13 with the air flow that collides and rises at the center. In the internal space of the adjustment section 8, negative pressure is generated by the operation of the fan filter unit 2, and the above-mentioned air flow is driven by this pressure difference. In addition, in order to assist such air circulation, a blower such as a fan (not shown) may be provided at each appropriate location as necessary.

[0043] It should be noted that the example shown here is a schematic diagram, and in an actual industrial clean room, in addition to what is shown in the diagram, various other facilities such as outdoor air conditioners, humidifiers, and rails and transport vehicles for transporting products are usually installed as necessary. However, such configurations that are not directly related to the gist of the present invention have been omitted from the illustration here as appropriate.

[0044] The air conditioning system of the first embodiment shown in Fig. 1 and Fig. 2 is advantageous in terms of space utilization efficiency compared to the conventional example shown in Fig. 12. In the conventional example of Fig. 12, in order to supply a generally downward airflow, even though it is a non-unidirectional airflow that dilutes and mixes widely to the target space S, a wide-area ceiling 1 is constructed as a cell ceiling or panel ceiling, and a fan filter unit 2 is arranged thereon. In the first embodiment shown in Fig. 1 and Fig. 2, adjustment units 8 are provided on both sides of the room, and the fan filter unit 2 is installed there, so a dropped ceiling that covers the entire upper part of the target space S is not necessary. In addition, in the area where the adjustment unit 8 is not provided, the height up to the ceiling 10 can be used, so more space can be used as a clean room compared to the example of Fig. 12, and it is easy to arrange, for example, tall devices and equipment. In addition, even when an existing building is used as an industrial clean room or when the building has a low floor height, it is easy to construct a clean room. In addition, the cost of installing a large-area cell ceiling and installing a dropped ceiling even though there is no ceiling transportation can be reduced. Since the space in which negative pressure occurs is small, the area on the body where dust-proofing measures are required can be minimized.

[0045] In addition, the first embodiment utilizes temperature stratification to efficiently cool the target space S, particularly the height close to the floor 13, which requires air conditioning, and is therefore advantageous in terms of air conditioning efficiency. In the conventional example shown in FIG. 12, the indoor air A1 is supplied to the entire area of ​​the target space S with a generally downward airflow, even though it is a non-unidirectional airflow that dilutes and mixes, so it was necessary to adjust the temperature to an appropriate level not only in the planar area but also in the height direction below the ceiling 1 where the fan filter unit 2 is installed, but in the case of the first embodiment, the return air A2 to be cooled is air recovered from a heat pool formed near the ceiling 10 above the equipment 5 above the floor 13 where the equipment 5 is placed. Since high-temperature air can be used as the cooling target, the temperature difference of the cooling medium in the dry coil can be made large, and the temperature of the cooling medium can be made high, so that the coefficient of performance of the cooling source, which is composed of a compressor, expansion valve, evaporator, condenser, etc. that form the refrigeration cycle, can be made large, and the efficiency of heat exchange is high. In addition, the number of rows of dry coils can be reduced, which reduces pressure loss and reduces the air transport energy, resulting in high heat exchange efficiency.

[0046] Furthermore, the indoor air A1 forms a temperature stratification, and the heated air automatically rises to the height of the adjustment section 8 due to density differences. This movement drives part of the air circulation described above, thereby also saving energy related to air transportation.

[0047] Furthermore, in this first embodiment, the Coanda effect is effectively utilized to allow the air supplied from the fan filter unit 2 to reach long distances. The indoor air A1 supplied to the target space S from the fan filter unit 2 is first sent downward and collides with the floor 13. The colliding indoor air A1 is redirected along the upper surface of the floor 13, and thereafter reaches a long distance from the fan filter unit 2 due to the Coanda effect, making it possible to efficiently deliver clean air to devices other than the equipment 5 located directly below the fan filter unit 2. This makes it possible to fully achieve a cleanliness level of, for example, around class 6.

[0048] Figures 5 and 6 show another example (second embodiment) of the device arrangement of an air conditioning system according to the present invention. In the first embodiment shown in Figures 1 and 2, the adjustment units 8 in which the fan filter units 2 are arranged are provided along opposing walls 7 of a room that is generally rectangular in plan view, and indoor air A1 is sent out from both ends of the room toward the center, but in this second embodiment, the adjustment unit 8 is provided along the wall 7 that forms one side of the room, and the fan filter units 2 arranged there send out indoor air A1 toward the opposite wall 7 where the adjustment unit 8 is not installed.

[0049] When the adjustment unit 8 and the fan filter unit 2 are arranged in this manner, the indoor air A1 sent downward from the fan filter unit 2 collides with the floor 13, and is blocked in three directions by the presence of the wall 7 located in one horizontal direction and the downward air flow in two directions (or the presence of the wall 7 located in two directions and the downward air flow in one direction) in the same way as in the first embodiment shown in Figs. 1 and 2, and is guided in the remaining direction (the direction in which the wall 7 on the opposite side as seen from the fan filter unit 2 is located), which is the desired direction. After that, the air does not peel off the floor surface between the devices 5 due to the Coanda effect, and crawls along the upper surface of the floor 13, receiving exhaust heat from the devices 5. As a result, some of the indoor air A1, which has slowed down its crawling speed by colliding with the devices 5 and received more exhaust heat, and its temperature has risen, moves upward due to the density difference caused by the temperature difference.

[0050] In the area near the wall 7 on the opposite side where the adjustment unit 8 is not arranged, the main stream of the indoor air A1 sent from the fan filter unit 2 side and moving along the floor 13 collides with the wall 7 and starts to rise. Although it is the main stream here, as it moves towards the wall, some of the airflow that receives the exhaust heat and rises is divided many times, and the air volume itself is reduced. This main stream collides with the wall, and the dynamic pressure of each airflow is reacquired as static pressure, and further changed in direction, and the dynamic pressure conversion starts to rise here. With this change in direction, the rising airflow rises without disturbing the stratified air conditioning layer. In addition, a part of the indoor air A1 moving in the desired direction along the floor 13 receives the exhaust heat from the equipment 5 located along the way and rises, and merges with the air flow guided along the floor 13 and the wall 7 above the floor 13. The rising indoor air A1 is sucked back into the adjustment unit 8 through the intake port 8b of the adjustment unit 8. In this way, as shown in Figure 5, air circulation is formed that is roughly half the air flow in the first embodiment (see Figure 1), and a target space S that is a clean room is realized, similar to the first embodiment.

[0051] 7 and 8 show yet another example (third embodiment) of the device arrangement of an air conditioning system according to the present invention. In this third embodiment, a total of two rows of fan filter units 2 are arranged on the inner undersides 8c of adjustment units 8 along opposing walls 7 in a room that is generally rectangular in plan view, similar to the first embodiment, but in addition, a third row of adjustment units 8 is provided in the area corresponding to the center of the room.

[0052] The third row of adjustment units 8 is arranged in a direction parallel to the first and second rows of adjustment units 8 located at both ends of the room, and is located closer to the second row than the center in a direction perpendicular to the arrangement of the first and second rows of adjustment units 8, assuming that the left adjustment unit 8 in Figures 5 and 6 is the first row and the right adjustment unit 8 is the second row. The third row of adjustment units 8 are arranged so that the side including the fan filter unit 2 faces the first row and the side including the intake port 8b faces the second row in a plan view.

[0053] 1 and 2, the indoor air A1 sent out from the fan filter unit 2 in the first row (left side) collides with the floor 13, and is blocked in three horizontal directions by the flow of indoor air A1 from the wall 7 and the adjacent fan filter unit 2, and is guided in the remaining direction (to the right), which is the desired direction. Similarly, the indoor air A1 sent out from the fan filter unit 2 in the second row (right side) is blocked in three horizontal directions by the flow of indoor air A1 from the wall 7 and the adjacent fan filter unit 2, and is guided in the remaining direction (to the left), which is the desired direction.

[0054] The indoor air A1 sent out from the fan filter unit 2 in the third row (center) also collides with the floor 13 and changes direction, but in this case, of the four horizontal directions seen from the flow of the indoor air A1, in one direction there is a flow of indoor air A1 sent out from the fan filter unit 2 in the second row and flowing to the left, and in the other direction there is a downward flow of indoor air A1 sent out from the adjacent fan filter unit 2 in the same third row (with regard to the indoor air A1 sent out from the fan filter units 2 located at both ends of the third row, the flow of indoor air A1 flowing in from the fan filter unit 2 in the second row exists in one direction, the downward flow of indoor air A1 sent out from the adjacent fan filter unit 2 in the third row exists in one direction, and the wall 7 is located in yet another direction). The flow of indoor air A1, which changes direction along the floor 13, is blocked by these and guided to the remaining desired direction (to the left).

[0055] The flow of indoor air A1 sent out from the fan filter units 2 in the first row and moving to the right along the upper surface of the floor 13, and the flow of indoor air A1 sent out from the fan filter units 2 in the third row and moving to the left along the upper surface of the floor 13 collide with each other at a position halfway between the first and third rows and start to rise. The rising airflow changes direction above the floor 13 and flows toward the inlets 8b of the first and third rows, and is sucked into the adjustment unit 8 from the inlets 8b as return air A2.

[0056] When the flow of indoor air A1 sent out from the second row of fan filter units 2 and moving leftward along the upper surface of the floor 13 reaches the vicinity of the third row of fan filter units 2, there is a flow of indoor air A1 sent out downward from the third row of fan filter units 2 ahead. At this point, the flow of indoor air A1 sent out from the second row of fan filter units 2 changes direction and begins to rise. The rising airflow changes direction again above the floor 13 and flows toward the intake port 8b of the second or third row of adjustment units 8, and is sucked into the adjustment units 8 from the intake port 8b as return air A2.

[0057] In this way, for the indoor air A1 sent out from the first and third rows of fan filter units 2, circulation is formed generally similar to that in the first embodiment shown in Figures 1 and 2, and for the indoor air A1 sent out from the second row of fan filter units 2, circulation is formed generally similar to that in the second embodiment shown in Figures 5 and 6. As a result, like the first and second embodiments described above, a target space S that is a clean room is realized.

[0058] The circulation of air as in each of the above-mentioned embodiments is achieved by skillfully arranging another air flow or a wall 7 to guide the flow of the indoor air A1 sent out from the fan filter unit 2. Specifically, first, the fan filter units 2 that send out the indoor air A1 downward are arranged in a line, so that the main direction of the indoor air A1 that is blown against the floor 13 and changed is limited to two directions perpendicular to the direction in which the fan filter units 2 are arranged. By placing the downward air flows adjacent to each other, the subsequent flow directions are restricted to each other. Furthermore, by further blocking one of the two directions with a wall 7 or another air flow (a downward, sideways, or upward air flow sent out from another fan filter unit 2), the direction of the indoor air A1 is guided to the desired direction.

[0059] The indoor air A1 thus sent out reaches a certain distance along the upper surface of the floor 13, where it collides with the wall 7 or another air flow, rises, and is sucked into the adjustment unit 8 through the intake port 8b. By appropriately arranging the wall 7 or another air flow at the position where the indoor air A1 reaches, the flow of the indoor air A1 is well guided even at the destination where it reaches, and is suitably taken in as return air A2 through the intake port 8b, thereby forming the air circulation as shown in Figs. 1, 5, and 7. The main feature of the present invention is that the indoor air A1 is sent downward from the fan filter unit 2 to collide with the floor 13, and the flow of the indoor air A1 reaches a long distance by utilizing the Coanda effect. However, if the downward flow of the indoor air A1 is simply made to collide with the floor 13, the flow will dissipate in all directions along the floor 13. Therefore, the flow of the indoor air A1 is guided by devising the arrangement of the fan filter unit 2 and the wall 7, and the circulation as described above is formed. In addition, the heat generated by the exhaust heat of the device 5 is also utilized to allow a certain amount of indoor air A1 to reach a long distance.

[0060] In this way, in each embodiment, by appropriately arranging the fan filter unit 2, the wall 7, etc., it is possible to appropriately guide the flow of the indoor air A1 in the desired direction with a simple configuration. Even in a large clean room, by appropriately combining these, it is possible to supply clean air at an appropriate temperature to every corner of the target space. Note that it is also possible to provide other objects or structures (such as a partition-like object) other than the air flow and the wall 7 to guide the flow of the indoor air A1.

[0061] Figures 9 to 11 show the results of a simulation of the air flow and conditions in a cleanroom designed based on the above-mentioned technical concept, with Figure 9 showing the distribution of air temperature, Figure 10 showing the concentration of particles in the air, and Figure 11 showing the distribution of air age. In addition, (A) in each figure shows a cross section of the space where the equipment is arranged, and (B) shows a cross section of the space between the equipment arrangements.

[0062] In the example shown here, it is assumed that four pieces of equipment 5 are arranged in the left-right direction in the target space S, which is a clean room. The distance from the air outlet of the fan filter unit 2 provided in the adjustment section 8 on the left in the figure to the wall 7 at the right end is set to about 20 m, and the heat load is calculated not only for the exhaust heat of the equipment 5 installed on the floor 13, but also for the heat generated by lighting and people (not shown). In addition, multiple pieces of equipment 5 are arranged in the depth direction (direction perpendicular to the paper surface), but are not shown in the figure.

[0063] An adjustment unit 8 is provided above the left end of the target space S, and air is sent downward from a fan filter unit 2 arranged on a lower surface 8c, collides with the floor 13, and proceeds toward the right end of the target space S. An intake port 8b is provided in the adjustment unit 8 located above the floor 13, and air that collides with the wall 7 at the right end of the target space S rises above the floor 13 and is then taken in by the intake port 8b.

[0064] In FIG. 9, areas with higher air temperatures are displayed in black, and areas with lower air temperatures are displayed in white. First, referring to (B), it can be seen that air circulates well in the cross section where no equipment 5 exists, and light-colored (low-temperature) air reaches the center of the target space S. Dark-colored (high-temperature) air forms a heat pool in the upper part of the target space S, and this is taken in from the intake port 8b as return air. Also, referring to (A) of FIG. 9, it can be seen that even though the equipment 5 is arranged in the direction of air circulation, air slips through between them, and light-colored (low-temperature) air reaches the right end. It can be seen that the light-colored (low-temperature) air is also distributed between the equipment 5, and that it successfully gets around between the equipment 5 to supply low-temperature air.

[0065] Next, FIG. 10 showing the particle concentration distribution in the air will be referred to. In FIG. 10, areas with higher particle concentration are displayed in black, and areas with lower particle concentration are displayed in white. In (B), it can be seen that in the cross section where the device 5 is not present, air with a low particle concentration reaches the right-hand end area along the floor surface. Also, in FIG. 10(A), it can be seen that air with a high particle concentration is stagnating near the floor surface just before the right end (the area slightly to the left of the right-hand end wall 7) when viewed from the air flow, but the particle concentration is low in the right-hand end area, and it can be seen that clean air reaches the opposite end of the fan filter unit 2.

[0066] Furthermore, reference is made to Fig. 11 which shows the distribution of air age. In Fig. 11, for the air sent out from the fan filter unit 2, areas with higher air age are displayed in black, and areas with lower air age are displayed in white. In both (A) and (B), the area with low air age near the floor surface on which the equipment 5 is placed continues to the right end, and it can be seen that the air age is kept low throughout the target space S (i.e., air is circulated efficiently).

[0067] When the air temperature at a height of 1,200 mm above the floor was set at 23°C and blown out from the fan filter unit 2, it was approximately 25.0°C near the right-hand wall 7, and the average value at a height of 1,200 mm was 24.3°C. The particle concentration at the same height was approximately 126 particles / m3 near the outlet of the fan filter unit 2. 3 At the right end near wall 7, the density was approximately 5,480 particles / m 3 , the average at a height of 1,200 mm is about 2,500 pieces / m 3 The age of the air at a height of 1,200 mm was 75.7 seconds near the wall 7 at the right end, and about 50.4 seconds on average. Thus, the results of this simulation show that even if the equipment 5 is placed on the floor, it is possible to supply young, clean, and sufficiently cool air at a required height within the target space S to positions far from the air outlet. In terms of cleanliness in clean rooms, it is easily possible to achieve up to around class 6.

[0068] In this way, according to the air conditioning system of this embodiment which is equipped with an adjustment section 8 having a fan filter unit 2 on its lower surface 8c and an intake port 8b on its upper surface 8a, and supplies air from the fan filter unit 2 toward the floor surface, the air supplied from the fan filter unit 2 can be delivered sufficiently far by utilizing the Coanda effect.

[0069] As described above, the air conditioning system for the clean room in each of the above embodiments comprises: a target space S in which is installed a device (equipment) 5 that needs to maintain its own temperature within a predetermined range while providing a thermal load to the surrounding air; an adjustment unit 8 that is provided above the floor 13, partitioned from the target space S, and forms a space at a higher level than the device (equipment) 5; a fan filter unit 2 that is provided on the lower surface 8c of the adjustment unit 8 and sends out air (room air) A1 downward toward the floor 13; an intake port 8b that is provided on the upper surface 8a of the adjustment unit 8 and connects the internal space of the adjustment unit 8 to the target space S; and a dry coil that is built into the adjustment unit 8 to circulate air from the intake port 8b by operation of the fan filter unit 2 and adjust the temperature of the air, and is configured so that the flow of air A1 sent out from the fan filter unit 2 toward the floor 13 is guided along the floor 13 in a desired direction perpendicular to the arrangement direction of the fan filter units 2. In this way, the area of ​​the installation surface of the fan filter unit 2 can be limited to the underside 8c of the adjustment section 8, while the Coanda effect and temperature stratification can be utilized to suitably supply the air A1 sent out from the fan filter unit 2 into the target space S.

[0070] The air conditioning system for the clean room in each embodiment is configured so that the flow of air A1, which is sent out from the fan filter unit 2 towards the floor 13 and guided along the floor 13, is guided in a desired direction by being blocked from the horizontal direction by a flow of air A1 sent out from another fan filter unit 2 or by the wall 7. In this way, the flow of air A1 can be suitably guided in a desired direction with a simple configuration.

[0071] In the air conditioning system for the clean room of each embodiment, the adjustment section 8 can be configured as a box-shaped structure equipped with the fan filter unit 2 and the suction port 8b.

[0072] In the air conditioning system for the clean room of each embodiment, the adjustment section 8 can also be configured as a duct-like structure extending horizontally and having a plurality of fan filter units 2 arranged along the longitudinal direction.

[0073] In the clean room air conditioning system of each embodiment, a hanging wall 9 extending downward from the vicinity of the air outlet of the fan filter unit 2 is provided on the lower surface 8c of the adjustment section 8. In this way, the flow of air A1 sent downward from the fan filter unit 2 is prevented from mixing with the flow of air A1 ascending in the nearby area, thereby making it possible to suppress the occurrence of a short circuit.

[0074] Therefore, according to each of the above-described embodiments, it is possible to reduce the area required for the installation surface of the fan filter unit 2, while maintaining a sufficient degree of cleanliness in the target space.

[0075] Incidentally, the air conditioning system for a clean room according to the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention. [Explanation of symbols]

[0076] 2 Fan filter unit 5 Equipment 6 Dry coil (cooling unit) 7. Wall 8 Adjustment part 8a Top 8b Intake port 8c Bottom 9 Hanging wall 13 Beds A1 Air (indoor air) S Target space

Claims

1. a target space in which a device that needs to maintain its own temperature within a predetermined range while providing a thermal load to the surrounding air is installed; An adjustment unit provided above the floor, partitioned from a target space, and forming a space at a level above the device; a fan filter unit provided on a lower surface of the adjustment unit and configured to blow air downward toward the floor; A suction port provided on an upper surface of the adjustment unit and communicating an internal space of the adjustment unit with a target space; a dry coil built into an adjustment unit for adjusting a temperature of air circulated from the suction port by operation of the fan filter unit, The main flow of air sent from the fan filter unit toward the floor collides with the floor, and then flows along the surface of the floor while forming a temperature stratification due to the Coanda effect. The main flow of air is guided along the floor in a desired direction perpendicular to the arrangement direction of the fan filter units, and is guided in the desired direction to an arrangement area of ​​the device away from the fan filter units in a plan view. The air flow is configured to prevent disturbance of the air throughout the room of the target space. A clean room air conditioning system characterized by:

2. The return air is drawn in through an intake port provided at a position on the other side of the upper surface of the adjustment unit, The fan filter unit is disposed on the underside of the adjustment unit at a position toward one side, and the intake air is blown downward.

2. The air conditioning system for a clean room according to claim 1 .

3. The fan filter unit and the wall of the target space are arranged so that at least a part of the main flow of air sent out from the fan filter unit flows downward along the wall of the target space and then further flows along the wall and floor of the target space.

2. The air conditioning system for a clean room according to claim 1 .

4. The air flow that is sent from the fan filter unit toward the floor and guided along the floor is configured to be guided in a desired direction by being blocked in a horizontal direction by an air flow sent from another fan filter unit or by a wall.

2. The air conditioning system for a clean room according to claim 1 .

5. The adjustment section is configured as a box-shaped structure including the fan filter unit and the suction port.

2. The air conditioning system for a clean room according to claim 1 .

6. The adjustment section is configured as a duct-like structure extending in a horizontal direction and having a plurality of the fan filter units arranged along the longitudinal direction.

2. The air conditioning system for a clean room according to claim 1 .

7. A hanging wall is provided on the lower surface of the adjustment portion, the hanging wall extending downward from the vicinity of the air outlet of the fan filter unit.

2. The air conditioning system for a clean room according to claim 1 .

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