Air Conditioning System

Abstract

Provided is a user-friendly air conditioning system. An air conditioning system (S) comprises: a fan filter unit (U) that has an air supply fan (Ua) for supplying air to a clean room (Rs); and a fan filter unit (V) that has an air return fan (Va) for returning or the like of air from the clean room (Rs). The air conditioning system (S) further comprises: a pressure sensor (30s) that is installed in the clean room (Rs); and a control device that controls one of the air supply fan (Ua) and the air return fan (Va) on the basis of the detection value of the pressure sensor (30s), and controls the other fan at a constant speed. It is possible to switch between controlling one of the air supply fan (Ua) and the air return fan (Va) on the basis of the detection value of the pressure sensor (30s) and the other fan at a constant speed.

Description

[Technical field]

[0001] The present invention relates to an air conditioning system. [Background technology]

[0002] Clean rooms with high air purity are used in the manufacture of semiconductors and precision machinery as well as in regenerative medicine and pharmaceutical manufacturing. Regarding the adjustment of room pressure in such clean rooms, for example, the technology described in Patent Document 1 is known. That is, Patent Document 1 describes that "...the air supply fan 22 of each FFU 20 is individually controlled so as to maintain the differential pressure measured by the differential pressure gauge 25 within a predetermined range." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-337675 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, the supply fans are controlled individually, but the rotation speed of the exhaust fan is not particularly adjusted. Therefore, for example, it is difficult to use a clean room that has been used as a negative pressure room as a positive pressure room for another purpose with the technology described in Patent Document 1.

[0005] Therefore, an object of the present invention is to provide an air conditioning system that is easy to use. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the air conditioning system according to the present invention includes a first unit having a first fan that supplies air to a clean room provided inside a specified room and a first filter provided on the blowing side of the first fan, and further includes a second unit having a second fan that returns air from the clean room, a duct shaft that guides air from the clean room to the specified room, a pressure sensor provided in the clean room; and a control unit that controls one of the first fan and the second fan based on a detection value of the pressure sensor and controls the other fan at a constant speed. Equipped with the predetermined room is a space formed by a side wall, a ceiling, and a floor surface, and the clean room is provided so as to be surrounded by the side wall, the ceiling, and the floor surface of the predetermined room in a vertical cross-sectional view, The duct shaft Along the side of the clean room The duct shaft extends in a vertical direction, and an upper end of the duct shaft is open, and air guided into the clean room via the first fan is returned to the specified room via the second fan and the duct shaft in this order. The first fan and the second fan are switchable between being controlled based on the detection value of the pressure sensor and being controlled at a constant speed. Other features will be described in the embodiments. Effect of the Invention

[0007] According to the present invention, it is possible to provide an air conditioning system that is easy to use. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is an explanatory diagram showing the layout of each room in the air conditioning system according to the first embodiment. [Diagram 2] FIG. 2 is an explanatory diagram showing the arrangement of a plurality of fan filter units included in the air conditioning system according to the first embodiment. [Diagram 3] FIG. 2 is an explanatory diagram showing the arrangement of a plurality of fan filter units included in the air conditioning system according to the first embodiment. [Figure 4] FIG. 1 is an explanatory diagram of an air conditioning system according to a first embodiment. [Diagram 5] FIG. 2 is a configuration diagram relating to control of an air supply side fan filter unit and a return air side fan filter unit provided in the air conditioning system according to the first embodiment. [Figure 6] FIG. 4 is a characteristic diagram showing the relationship between the rotation speed and air volume of a return air fan provided in the air conditioning system according to the first embodiment. [Figure 7] FIG. 11 is an explanatory diagram of an air conditioning system according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] First Embodiment FIG. 1 is an explanatory diagram showing the layout of each room in an air conditioning system S according to the first embodiment. In Fig. 1, the direction of air flow when a specific door (e.g., door Dm) is opened is indicated by a dashed arrow with a white outline. In the first embodiment, the adjustment of the room pressure in each clean room will be mainly described, but the adjustment of the air temperature and humidity in addition to the room pressure is also included in "air conditioning". The adjustment of only the room pressure is also included in "air conditioning". In this specification, the first embodiment is a reference embodiment.

[0010] The air conditioning system S is a system that adjusts the room pressure of multiple clean rooms such as the pretreatment room R3 and the preparation room R7, and is installed in, for example, a regenerative medicine facility. In such an air conditioning system S, multiple rooms with different air cleanliness levels are often installed. In order to prevent air from leaking from a room with a low cleanliness level to a room with a high cleanliness level, a difference in room pressure is set between adjacent rooms.

[0011] For example, the pre-treatment room R3 shown in Fig. 1 has a higher air cleanliness and room pressure than the primary changing room R2. Therefore, when a worker opens the door De to enter the pre-treatment room R3 from the primary changing room R2, air flows from the high-pressure pre-treatment room R3 to the low-pressure primary changing room R2 as shown by the dashed arrow in Fig. 1, but the reverse flow rarely occurs. This prevents dust from entering the pre-treatment room R3 from the primary changing room R2, and maintains the cleanliness of the pre-treatment room R3.

[0012] However, due to the above-mentioned air movement, the room pressure in the primary changing room R2 temporarily increases, while the room pressure in the pre-treatment room R3 temporarily decreases. Each time the door De is opened and closed, such fluctuations in room pressure occur. Therefore, in the first embodiment, the fluctuations in room pressure in each clean room are suppressed by controlling each device described below.

[0013] In addition, in Fig. 1, when a dashed white arrow is drawn from one of two adjacent clean rooms to the other, it is assumed that the room pressure of the one clean room is higher than that of the other. Also, among the multiple clean rooms and doors marked with reference numbers in Fig. 1, the description of some of them will be omitted as appropriate. For example, the description of some of the multiple doors Da to Dz, Dα, Dβ, Dγ, and Dδ will be omitted.

[0014] In the example of FIG. 1, the loading and unloading room R1, the first changing room R2, the pre-treatment room R3, the undressing room R10, and the front room R11 are arranged next to each other in this order. For example, when an operator works in the pre-treatment room R3, he passes through each clean room in the above-mentioned order. The pre-treatment room R3 is provided with a biohazard cabinet BSC1 for handling a specific sample. Samples used in the biohazard cabinet BSC1 are carried in through the front room R4 and the pass box PB1 in this order. On the other hand, products (cell processed products, etc.) created in the biohazard cabinet BSC1 are carried out through the pass box PB2 and the front room R5 in this order. The pass boxes PB1 and PB2 are spaces for suppressing contamination (sample contamination).

[0015] In addition, the dressing room R1, the first dressing room R2, the second dressing room R6, the airlock AL1, the preparation room R7, the airlock AL2, the dressing room R10, and the anteroom R11 are arranged next to each other in this order. For example, when an operator works in the preparation room R7, he passes through each clean room in the above-mentioned order. The airlocks AL1 and AL2 are spaces to prevent dust from entering the highly clean preparation room R7, and the room pressure is higher than that of the other clean rooms.

[0016] In addition, samples and the like can be taken in and out between the preparation chamber R7 and the pretreatment chamber R3 via the pass box PB5. The preparation chamber R7 has a higher cleanliness level than the pretreatment chamber R3, and the chamber pressure is also higher than the pretreatment chamber R3. This makes it possible to suppress contamination (sample contamination) when the door Dx or door Dy is opened.

[0017] In the example of Fig. 1, biohazard cabinets BSC2 and BSC3 for handling predetermined samples are provided in preparation room R7. Products (cell processed products, etc.) prepared in biohazard cabinets BSC2 and BSC3 are carried out via pass box PB3 and front room R8 in that order. Meanwhile, waste materials, etc. are carried out via pass box PB4 and front room R9 in that order.

[0018] The changing room R1, the first changing room R2, the pre-treatment room R3, the anterooms R4 and R5, the second changing room R6, the preparation room R7, the anterooms R8 and R9, the changing room R10, the anteroom R11, and the airlocks AL1 and AL2 shown in Fig. 1 correspond to "clean rooms." In addition to the fan filter units 3, 7, 9, 11, 13, and 18 shown in Fig. 1, the air handling unit 50 will be described later.

[0019] FIG. 2 is an explanatory diagram showing the arrangement of a plurality of fan filter units. In Fig. 2, air flows are indicated by solid arrows, while signal lines are indicated by dashed arrows. Fig. 2 also illustrates some of the clean rooms in Fig. 1 (floor plan), while Fig. 3 shows the remaining clean rooms. Figs. 2 and 3 are schematic cross-sectional views that focus on the air flow, for example, air being led from preparation chamber R7 through duct shaft DS2 to chamber C.

[0020] Duct shaft DS1 shown in Fig. 2 is a space that guides air from preparation chamber R7 to chamber C, although not shown in Fig. 1. Other duct shafts DS2 to DS5 are also spaces that guide air from predetermined clean rooms to chamber C, although not shown in Fig. 1. These duct shafts DS1 to DS5 are air ducts (not shown) provided in gaps between adjacent clean rooms, etc.

[0021] As shown in FIG. 2, the air conditioning system S includes an air handling unit 50, fan filter units 1-11, and pressure sensors 31-36. The air handling unit 50 is a device that adjusts the temperature of air, etc. As shown in Fig. 2, the air handling unit 50 includes a filter 51, a cooling coil 52, a fan 53, and an inverter 54.

[0022] The filter 51 collects dust from the air flowing from the preparation chamber R7 through the duct shaft DS1 toward the cooling coil 52. The cooling coil 52 is a heat exchanger in which heat is exchanged between the air that has passed through the filter 51 and a refrigerant that flows through a heat transfer tube (not shown). The fan 53 is a blower that pressure-feeds the air that has undergone heat exchange in the cooling coil 52 to the chamber C through the duct D1. The inverter 54 controls the motor (not shown) of the fan 53.

[0023] As shown in FIG. 2, the outlet of the fan 53 and the chamber C are connected via a duct D1. The duct D1 is an air duct that guides air whose temperature, etc. have been adjusted by the air handling unit 50 to the chamber C. The duct D1 is provided with a damper B1. For example, the damper B1 is set to a predetermined opening during a test run of the air conditioning system S, and is maintained at the predetermined opening during the air conditioning operation thereafter. In addition to the duct D1, air whose temperature, etc. have been adjusted is guided to the chamber C via another duct D2. In this way, the air supplied via the ducts D1 and D2 join in the chamber C.

[0024] The chamber C is a space above the ceiling of each clean room such as the preparation room R7. Specifically, the chamber C includes the ceiling E of each clean room such as the preparation room R7, an upper plate Ta, and side plates Tb and Tc. In the example of FIG. 2, the upper plate Ta is provided at a position higher than the ceiling E, and the plate surface of the upper plate Ta is approximately parallel to the surface of the ceiling E. In addition, a side plate Tb is provided so as to connect the edge of the ceiling E and the upper plate Ta on one lateral side. Similarly, a side plate Tc is provided so as to connect the edge of the ceiling E and the edge of the upper plate Ta on the other lateral side.

[0025] As shown in Fig. 2, the spaces above the ceilings of the multiple clean rooms are formed as one chamber C (common space). Air whose temperature and other parameters have been adjusted to a predetermined level is introduced into the chamber C, and is then introduced from the chamber C to the preparation room R7 by the fan filter units 1 and 2 (first units) on the air supply side. The same is true for the other clean rooms. In addition, the multiple clean rooms include a mixture of rooms with different target room pressures (set pressures).

[0026] According to such a configuration, since there is no particular need to provide a duct in the chamber C (or in place of the chamber C) for guiding air to the fan filter units 1, 2, etc., the configuration of the air conditioning system S can be simplified. Therefore, it becomes easier to install gas piping in the chamber C and to lay communication lines and power lines, and costs can be reduced.

[0027] The fan filter unit 1 (first unit) shown in FIG. 2 is a device that supplies air from the chamber C to the preparation room R7, and is embedded in the ceiling E. The fan filter unit 1 includes an air supply fan 1a (first fan) and a filter 1b. The air supply fan 1a is a blower that supplies air from the chamber C to the preparation room R7 (clean room). As shown in FIG. 2, the suction side of the air supply fan 1a communicates with the chamber C (common space).

[0028] The filter 1b collects dust from the air flowing from the air supply fan 1a to the preparation room R7, and is provided on the blowing side of the air supply fan 1a. For example, a HEPA (High Efficiency Particulate Air Filter) or a ULPA (Ultra Low Penetration Air Filter) is used as the filter 1b. A housing (not shown) that houses the air supply fan 1a and the filter 1b is fitted into an opening in the ceiling E of the preparation room R7 and fixed with metal fittings or the like. Another fan filter unit 2 provided on the ceiling E of the preparation room R7 has the same configuration as the fan filter unit 1 described above.

[0029] The fan filter unit 3 (second unit) shown in Fig. 2 is a device that exhausts and returns air from the preparation room R7. Note that "return air" from the preparation room R7 refers to returning at least a part of the air flowing out from the preparation room R7 to this preparation room R7. Also, in Fig. 2, for simplification, the fan filter unit 3 is illustrated below the floor G of the preparation room R7, but as shown in Fig. 1, the fan filter unit 3 is embedded in the wall of the space R12 adjacent to the preparation room R7 via the door Dp.

[0030] As shown in Fig. 2, the fan filter unit 3 includes a return air fan 3a (second fan) and a filter 3b. The return air fan 3a is a blower that exhausts and returns air from the preparation room R7 (clean room). As shown in Fig. 2, the suction side of the return air fan 3a communicates with the chamber C (common space) via a duct shaft DS2.

[0031] The filter 3b collects dust from the air flowing from the preparation chamber R7 to the return air fan 3a, and is provided on the suction side of the return air fan 3a. For example, HEPA or ULPA is used as the filter 3b. The filter 3b also functions as a resistor (air resistance) when air flows out of the preparation chamber R7, making it easier to maintain the preparation chamber R7 at a relatively high room pressure. A housing (not shown) that houses the return air fan 3a and the filter 3b is fitted into an opening in the wall that forms the above-mentioned space R12 (see FIG. 1) and fixed with metal fittings or the like.

[0032] The pressure sensor 31 shown in Fig. 2 is a sensor that detects the room pressure of the preparation chamber R7 (clean room) and is provided in the preparation chamber R7. The air supply fans 1a, 2a and the return air fan 3a are controlled so that the room pressure of the preparation chamber R7 becomes a predetermined target pressure (set pressure). Note that the room pressure of a general room (not shown) provided outside each clean room may be used as a reference pressure when detecting the room pressure of the preparation chamber R7. In addition to the detected value of the pressure of the chamber C, a predetermined pressure value set in advance may be used as the reference pressure.

[0033] The gaps K1 and K2 shown in Fig. 2 are ventilation passages through which air leaves the preparation chamber R7. One of the gaps, K1, is, for example, a gap between a packing (not shown) at the lower end of a door Dq (see Fig. 1) that separates the preparation chamber R7 from a space R13 (see Fig. 1) and the floor surface of the preparation chamber R7. The space R13 shown in Fig. 1 is connected to the suction side of the air handling unit 50 via a duct shaft DS1 (see Fig. 2). Also, the height position of the lower end of the packing of the door Dq is adjustable so that the size of the gap K1 can be adjusted as appropriate.

[0034] The other gap K2 shown in FIG. 2 is, for example, a gap between a packing (not shown) at the lower end of the door Dp that separates the preparation chamber R7 and the space R12 (see FIG. 1) and the floor surface of the preparation chamber R7. The space R12 shown in FIG. 1 is provided on the suction side of the return air fan 3a (see FIG. 2) and communicates with the chamber C (see FIG. 2) via the duct shaft DS2 (see FIG. 2). The height position of the lower end of the packing of the door Dp is adjustable so that the size of the gap K2 can be adjusted. The sizes (opening ratios) of the gaps K1 and K2 are appropriately adjusted during the design or trial operation of the air conditioning system S based on the volume of the preparation chamber R7 as well as the number of ventilations per unit time and the target pressure.

[0035] 2, a thin plate H2 having a plurality of holes is installed at the upper end of the duct shaft DS2. Then, while the supply air fans 1a, 2a and the return air fan 3a are in operation, a portion of the air guided from the preparation chamber R7 to the duct shaft DS2 through the gap K2 is returned (i.e., returned) to the chamber C through the plurality of holes in the thin plate H2. Meanwhile, the remainder of the air guided to the lower part of the duct shaft DS2 is sucked into the return air fan 3a and exhausted to the outside.

[0036] In this way, when the return air fan 3a (second fan) exhausts and returns air from the preparation room R7 (clean room), the suction side of the supply air fan 1a (first fan) and the suction side of the return air fan 3a (second fan) are each connected to the chamber C (common space). This allows a portion of the highly clean air in the preparation room R7 to be reused for air conditioning in each clean room. Although the pressure in the chamber C fluctuates slightly due to the return air to the chamber C by the return air fan 3a, there is little risk of this having a negative effect on maintaining the room pressure in each clean room.

[0037] As shown in FIG. 2, a fan filter unit 4 is embedded in the ceiling E of the front room R9. A pressure sensor 32 is also provided in the front room R9. The air supply fan 4a is controlled based on the detection value of the pressure sensor 32 so that the room pressure in the front room R9 is set to a predetermined target pressure. Note that in FIG. 2, an arrow is shown pointing from the floor G of the front room R9 to the bottom of the page, but the air in the front room R9 is exhausted through, for example, a gap between a packing (not shown) at the bottom end of the door Dw (see FIG. 1) and the floor surface of the front room R9. Note that the same applies to the other front rooms R8.

[0038] A fan filter unit 6 (first unit) equipped with a supply air fan 6a (first fan) and a filter 6b is embedded in the ceiling E of the airlock AL2 shown in FIG. 2. A fan filter unit 7 (second unit) equipped with a return air fan 7a (second fan) and a filter 7b is embedded in the side wall of the airlock AL2. A pressure sensor 34 for detecting the room pressure is provided in the airlock AL2. The supply air fan 6a and the return air fan 7a are controlled so that the room pressure in the airlock AL2 is set to a predetermined target pressure. The air blown out from the return air fan 7a is returned to the chamber C via the duct shaft DS3 and multiple holes in the thin plate H3 in sequence.

[0039] In this way, when the return air fan 7a (second fan) returns air from airlock AL2 (clean room) but does not exhaust air from airlock AL2, the suction side of the supply air fan 6a (first fan) and the blowing side of the return air fan 7a (second fan) are each connected to chamber C (common space). Note that the configurations relating to room pressure adjustment in the other airlock AL1 and secondary changing room R6 are similar to those in airlock AL2, so a description thereof will be omitted. Next, the configurations relating to room pressure adjustment in the remaining rooms not shown in FIG. 2 among the rooms shown in FIG. 1 will be described with reference to FIG. 3.

[0040] FIG. 3 is an explanatory diagram showing the arrangement of a plurality of fan filter units. It should be noted that the ceiling E shown in Fig. 3 is the same as that shown in Fig. 2. The chamber C shown in Fig. 3 is also the same as that shown in Fig. 2. 3 is a device that supplies air from chamber C to primary changing room R2 (clean room), and is embedded in the ceiling E. Fan filter unit 12 includes supply fan 12a (first fan) and filter 12b.

[0041] The fan filter unit 13 (second unit) is a device that exhausts air from the primary changing room R2 (clean room). Thus, the example in Fig. 3 differs from the above-mentioned fan filter units 3, 7, 9, and 11 (see Fig. 2) in that the fan filter unit 13 is not used for return air. Also, for simplification, Fig. 3 illustrates the fan filter unit 13 on the underside of the floor G of the primary changing room R2, but as shown in Fig. 1, the fan filter unit 13 is embedded in the wall that separates the primary changing room R2 from the outside.

[0042] 3, the fan filter unit 13 includes an exhaust fan 13a (second fan) and a filter 13b. A pressure sensor 37 for detecting the room pressure is provided in the primary changing room R2. The supply air fan 12a and the exhaust fan 13a are controlled so that the room pressure in the primary changing room R2 becomes a predetermined target pressure.

[0043] The configurations of the pressure adjustment of the dressing and undressing room R1 and the anterooms R4, R5, and R11 shown in Fig. 3 are the same as the anteroom R9 (see Fig. 2) described above, so their explanations will be omitted. Also, the configuration of the pressure adjustment of the changing room R10 shown in Fig. 3 is the same as the primary changing room R2 described above, so their explanations will be omitted.

[0044] Fan filter units 20-22 are embedded in the ceiling E of pre-treatment chamber R3 shown in Fig. 3. The intake sides of supply fans 20a, 21a provided in fan filter units 20, 21 (first unit) communicate with chamber C. Meanwhile, the exhaust side of exhaust fan 22a provided in fan filter unit 22 (second unit) is open to the outside. A pressure sensor 43 is provided in pre-treatment chamber R3. The supply fans 20a, 21a and exhaust fan 22a are controlled so that the chamber pressure in pre-treatment chamber R3 becomes a predetermined target pressure.

[0045] A part of the air supplied to the pre-treatment chamber R3 by the driving of the air supply fans 20a and 21a is exhausted by the exhaust fan 22a. The remaining air is led to the air handling unit (not shown) via the gap K3, the duct shaft DS6, and the duct D3 shown in Fig. 3 in this order. The opening degree of the damper B3 provided in the duct D3 is maintained at a predetermined setting during the test run or the like.

[0046] The "first unit" having the "first fan" that supplies air to the "clean room" includes fan filter units 1, 2, 4 to 6, 8, and 10 shown in FIG. 2 as well as fan filter units 12, 14 to 17, and 19 to 21 shown in FIG. Furthermore, the "second unit" having a "second fan" that performs at least one of exhausting air from or returning air to the "clean room" includes fan filter units 3, 7, 9, and 11 shown in Fig. 2 as well as fan filter units 13, 18, and 22 (see Fig. 5) shown in Fig. 3. Next, the details of the room pressure adjustment in each clean room will be described with reference to Fig. 4.

[0047] FIG. 4 is an explanatory diagram of the air conditioning system S. In addition, in order to make the explanation easier to understand, Fig. 4 shows two arbitrary clean rooms Rs and Rt selected from the multiple clean rooms shown in Fig. 2 and Fig. 3. The configuration for adjusting the room pressure of the clean rooms Rs and Rt is similar to that of the secondary changing room R6 (see Fig. 2) and the airlocks AL1 and AL2 (see Fig. 2). In other words, the air sent into the clean room Rs by the supply air fan Ua is returned to the chamber C via the duct shaft DS7 by the return air fan Va. The same applies to the supply air and return air of the other clean room Rt. Also, dampers (not shown) as air resistance may be provided near the upper ends of the duct shafts DS7 and DS8.

[0048] However, the following explanation can also be applied to the room pressure adjustment of each clean room, such as the preparation room R7 (see Figure 2) where both exhaust and return air are performed by the return air fan 3a (see Figure 2), as well as the primary changing room R2 (see Figure 3) where an exhaust fan 13a (see Figure 3) is installed.

[0049] In the following, as an example, a case will be described in which one clean room Rs is used as a "positive pressure room" and the other clean room Rt is used as a "negative pressure room." Here, a "positive pressure room" is a clean room in which the room pressure is set relatively high to suppress the inflow of air from another clean room adjacent to it through a door. Also, "positive pressure" refers to a room pressure higher than a preset reference pressure.

[0050] On the other hand, a "negative pressure room" is a clean room in which the room pressure is set relatively low to prevent viruses and the like from leaking through a door into adjacent clean rooms when, for example, infectious viruses or radioactive materials are handled. Also, "negative pressure" refers to a room pressure lower than a preset reference pressure. Note that the reference pressure for "positive pressure" or "negative pressure" may be the room pressure of a specific clean room or the room pressure of a general room (not shown) other than a clean room.

[0051] FIG. 5 is a configuration diagram relating to control of the fan filter unit U on the supply air side and the fan filter unit V on the return air side. As shown in Fig. 5, the fan filter unit U (first unit) on the air supply side includes an air supply fan Ua (first fan) and a filter Ub. The air supply fan Ua is a blower that supplies air to the clean room Rs (see Fig. 4), and includes a fan body Uaf and a fan motor Uam. The return air side fan filter unit V (second unit) includes a return air fan Va (second fan) and a filter Vb. The return air fan Va is a blower that returns air from the clean room Rs (see FIG. 4), and includes a fan body Vaf and a fan motor Vam.

[0052] The fan bodies Uaf and Vaf may be, for example, axial fans such as propeller fans. The fan motors Uam and Vam may be, for example, DC motors. The pressure sensor 30s shown in Fig. 5 is a sensor that detects the room pressure of the clean room Rs (see Fig. 4) and is provided in the clean room Rs.

[0053] The control device 60 (control unit) is a device that controls the supply air fan Ua and the return air fan Va. In the example of FIG. 5, the input side of the control device 60 is connected to the pressure sensor 30s via wiring, while the output side is connected to the supply air fan Ua and the return air fan Va via wiring. Although not shown, the control device 60 is configured to include electronic circuits such as a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and various interfaces. Then, a program stored in the ROM is read and expanded in the RAM, and the CPU executes various processes. The control device 60 may be configured to include a PLC (Programmable Logic Controller: not shown).

[0054] 5 shows an example in which the supply air fan Ua and the return air fan Va are connected to one control device 60, but a control device (not shown) for the supply air fan Ua and a control device (not shown) for the return air fan Va may be provided separately. Also, one control device may control the supply air fans and return air fans of multiple clean rooms.

[0055] When the clean room Rs (see FIG. 4) is used as a positive pressure room, the control device 60, for example, drives the supply air fan Ua at a constant speed while controlling the return air fan Va based on the detection value of the pressure sensor 30s. Driving the supply air fan Ua at a "constant speed" means that the rotation speed of the supply air fan Ua is constant regardless of the detection value of the pressure sensor 30s. When driving the supply air fan Ua at a predetermined rotation speed (fixed value), the control device 60 sets the rotation speed (i.e., air volume) of the supply air fan Ua so that ventilation of the clean room Rs is performed a predetermined number of times per unit time. This makes it possible to maintain the cleanliness of the clean room Rs at a predetermined level. Note that the degree of "constant" in the "constant speed" does not have to be strictly "constant" as long as it is effective.

[0056] Furthermore, the control device 60 controls the return air fan Va based on the detection value of the pressure sensor 30s so that the room pressure in the clean room Rs (see FIG. 4) becomes a predetermined target pressure (set pressure). For example, when the room pressure in the clean room Rs exceeds the target pressure, the control device 60 increases the rotation speed of the return air fan Va to a predetermined level. This increases the flow rate of air flowing out from the clean room Rs (see FIG. 4) to the duct shaft DS7 (see FIG. 4). On the other hand, the supply air fan Ua is driven at a constant speed as described above. As a result, the room pressure in the clean room Rs, which temporarily increased, is returned to the target pressure.

[0057] Furthermore, when the room pressure in the clean room Rs (see FIG. 4) falls below the target pressure, the control device 60 reduces the rotation speed of the return air fan Va to a predetermined value. As a result, the temporarily increased room pressure in the clean room Rs is returned to the target pressure. In this way, the control device 60 changes the rotation speed of the return air fan 3a based on the detection value of the pressure sensor 30s, thereby maintaining the room pressure in the clean room Rs at a predetermined target pressure. When the clean room Rs is used as a positive pressure room, as described above, it is often better to set the supply air fan Ua to a constant speed while setting the return air fan Va to a variable speed based on the room pressure.

[0058] FIG. 6 is a characteristic diagram showing the relationship between the rotation speed and air volume of the return air fan. In FIG. 6, the horizontal axis represents the rotation speed of the return air fan Va (see FIG. 5), and the vertical axis represents the air volume of the return air fan Va. As shown in FIG. 6, the higher the rotation speed of the return air fan Va, the larger its air volume. In addition, since a DC motor, for example, is used for the fan motor Vam (see FIG. 5) of the return air fan Va, the rotation speed and the air volume have a linear relationship (proportional relationship). Therefore, there is an advantage that the return air fan Va makes it easier to finely adjust the air volume compared to adjusting the air volume with a damper (not shown) whose opening-air volume characteristic has a nonlinear relationship. In addition to the return air fan Va, the supply air fan Ua (see FIG. 5) also has the same characteristics as those in FIG. 6.

[0059] For the return air fan Va (see FIG. 5), a lower limit N1 of the rotation speed and a corresponding lower limit Q1 of the air volume are preset, as shown in FIG. 6. Similarly, an upper limit N2 of the rotation speed of the return air fan Va and a corresponding upper limit Q2 of the air volume are also preset. In particular, focusing on the lower limit Q1 of the air volume of the return air fan Va, a specific numerical example thereof is 50 [m 3 / h], which is the lower limit of the air volume when adjusting the air volume with a conventional damper (not shown) (150 [m 3 / h]. As described above, the return air fan Va has a linear relationship between the rotation speed and air volume characteristics, so the control device 60 can fine-tune the air volume of the return air fan Va around the lower limit Q2. Therefore, compared to a case where the air volume is adjusted using a damper (not shown), the room pressure can be adjusted with high precision, and the power consumption of the air conditioning system S (see FIG. 4) can be significantly reduced.

[0060] Next, the control when the clean room Rt shown in Fig. 4 is used as a negative pressure room will be described. When the clean room Rt is used as a negative pressure room, the control device 60 (see Fig. 5) drives the return air fan Za (see Fig. 4) at a constant speed while controlling the supply air fan Wa (see Fig. 4) based on the detection value of the pressure sensor 30t (see Fig. 4), for example. Note that since the supply air fan Wa also has a linear rotation speed-air volume characteristic (see Fig. 6), it is easy to fine-tune the rotation speed of the supply air fan Wa near the lower limit value Q1 (see Fig. 6) of the air volume. Therefore, the room pressure of the clean room Rt can be maintained with high accuracy while reducing the power consumption of the air conditioning system S (see Fig. 4).

[0061] Furthermore, taking into consideration the volume of the clean room Rt, the target cleanliness and room pressure, the capacity of the supply air fan Wa and the return air fan Za, etc., when using the clean room Rt as a negative pressure room, it is often better to set the supply air fan Wa to a variable speed based on the room pressure, while setting the return air fan Za to a constant speed.

[0062] 4 has been used as a positive pressure room, but at some point the use of the clean room Rs may change to a negative pressure room. In such a case, the control device 60 controls the supply air fan Ua, which has been driven at a constant speed until then, based on the detection value of the pressure sensor 30s, and switches the return air fan Va, which has been driven at a variable speed until then, to be driven at a constant speed.

[0063] 4 has been used as a negative pressure room, but at some point the use may change to using this clean room Rt as a positive pressure room. In such a case, the control device 60 switches the supply air fan Wa, which has been driven at a variable speed, to a constant speed, and controls the return air fan Za, which has been driven at a constant speed, based on the detection value of the pressure sensor 30t.

[0064] In this way, the control device 60 (control unit) controls one of the supply air fan Ua (first fan) and the return air fan Va (second fan) based on the detection value of the pressure sensor 30s, and controls the other at a constant speed. The control device 60 is also configured to be able to switch between the supply air fan Ua and the return air fan Va, which is controlled based on the detection value of the pressure sensor 30s, and which is controlled at a constant speed. In other words, the room pressure of the clean room Rs can be switched from one of positive pressure and negative pressure to the other. The above-mentioned "switching" may be performed by a user's operation via an input means (not shown). This allows the clean room Rs to be selectively used as a positive pressure room or a negative pressure room depending on the purpose. The same can be said for another clean room Rt. Therefore, the workload and costs can be significantly reduced compared to when a separate positive pressure or negative pressure clean room is provided.

[0065] When switching the clean room Rs from one of a positive pressure room and a negative pressure room to the other, the control device 60 may stop the supply air fan Ua and the return air fan Va once and then drive them again. Also, the control device 60 may switch the control method for each fan while continuing to drive the supply air fan Ua and the return air fan Va.

[0066] <Effects> According to the first embodiment, the supply air fan Ua (see FIG. 4) and the return air fan Va (see FIG. 4) are configured to be switchable between being controlled based on the detection value of the pressure sensor 30s (see FIG. 4) and being controlled at a constant speed. Therefore, one clean room Rs can be selectively used as a positive pressure room or a negative pressure room, so that an air conditioning system S that is easy for users to use can be provided. Also, compared to the case where a positive pressure room or a negative pressure room (not shown) is separately provided, the workload and costs can be significantly reduced, so that it can contribute to society.

[0067] Also, since there is no particular need to provide ducts (not shown) for guiding air to the clean rooms Rs, Rt or ducts (not shown) for guiding air from the clean rooms Rs, Rt to the outside, it is possible to simplify the configuration of the air conditioning system S. Also, compared to the case where a duct (not shown) is provided in the chamber C (or provided in place of the chamber C), the construction period for installing the air conditioning system S can be shortened, and therefore the cost required for installation can be reduced.

[0068] Furthermore, in the conventional configuration in which the room pressure is adjusted by a damper (not shown) provided in a duct (not shown), in addition to the air pressure loss in the duct, the nonlinearity of the damper opening-air volume characteristic and the like tend to cause response delays and overshoots in adjusting the room pressure in the clean room. In contrast, in the first embodiment, for example, the room pressure in the clean room Rs (see FIG. 4) is adjusted by the return air fan Va or the supply air fan Ua, so the above-mentioned pressure loss and response delays hardly occur. In addition, since the rotation speed-air volume characteristic of the return air fan Va or the supply air fan Ua is linear (see FIG. 6), the room pressure in the clean room Rs can be maintained with high accuracy. The same can be said for the other clean rooms.

[0069] Second Embodiment The second embodiment differs from the first embodiment in that no chamber is provided in the ceiling of the clean room. The second embodiment also differs from the first embodiment in that two clean rooms Rs, Rt (see FIG. 7) are provided in a relatively large large room Ro (see FIG. 7). The configuration and control of the fan filter units U, W on the supply air side and the fan filter units V, Z on the return air side are the same as those of the first embodiment (see FIG. 4 and FIG. 5). The control device 60 is also capable of switching the clean rooms Rs, Rt from one of the positive pressure room and the negative pressure room to the other, as in the first embodiment. Therefore, only the parts different from the first embodiment will be described, and the explanation of the overlapping parts will be omitted.

[0070] FIG. 7 is an explanatory diagram of an air conditioning system SA according to the second embodiment. In the example of FIG. 7, two clean rooms Rs and Rt are provided in the large room Ro. A filter unit F4 is provided on the ceiling of the large room Ro. The filter unit F4 collects dust from the air flowing through the duct D4. For example, HEPA or ULPA is used as the filter unit F4. The air that has passed through the filter unit F4 is led to the space of the large room Ro. A damper B4 is provided in the duct D4 near the filter unit F4. For example, the damper B4 is set to a predetermined opening degree during a test run of the air conditioning system SA, and is maintained at the predetermined opening degree during the subsequent air conditioning operation.

[0071] The gaps Ka and Kb shown in Fig. 7 are ventilation paths through which air flows out from the large room Ro. The air is guided to an air handling unit (not shown) through the gaps Ka and Kb and duct D5 in this order. The air, whose temperature and other properties have been adjusted in the air handling unit (not shown), is returned to the large room Ro through another duct D4.

[0072] As shown in Fig. 7, an air supply fan filter unit U (first unit) is provided on the ceiling of the clean room Rs. A return air fan filter unit V (second unit) is provided on the side wall of the clean room Rs. Air introduced into the clean room Rs via the air supply fan Ua is returned to the space of the large room Ro via the return air fan Va and duct shaft DS7 in this order. The same is true for the other clean room Rt.

[0073] As shown in Figure 7, when the return air fan Va (second fan) returns air from the clean room Rs but does not exhaust air from the clean room Rs, the suction side of the supply air fan Ua (first fan) and the blowing side of the return air fan Va (second fan) are connected to the space of the large room Ro (common space).

[0074] The control device 60 (see FIG. 5) is configured to be able to switch between controlling the supply air fan Ua (first fan) and the return air fan Va (second fan) based on the detection value of the pressure sensor 30s and controlling them at a constant speed. This allows the clean room Rs to be selectively used as a positive pressure room or a negative pressure room. Note that the room pressure adjustment of the clean rooms Rs and Rt is the same as in the first embodiment, so a description thereof will be omitted.

[0075] <Effects> According to the second embodiment, even in a configuration in which the clean rooms Rs, Rt are provided in the large room Ro, the clean rooms Rs, Rt can be selectively used as positive pressure rooms or negative pressure rooms, so that an air conditioning system SA that is easy for users to use can be provided. Also, compared to the case where a positive pressure room or a negative pressure room is separately provided, the workload and costs can be significantly reduced.

[0076] <<Variations>> Although the air conditioning systems S, SA according to the present invention have been described above with reference to the respective embodiments, the present invention is not limited to these descriptions and various modifications can be made. For example, in each embodiment, no particular reference is made to setting the rotation speed when the supply air fan Ua (see FIG. 5) or the return air fan Va (see FIG. 5) is controlled at a constant speed, but the following may be done. That is, the air volume of the fan controlled at a constant speed out of the supply air fan Ua (first fan) and the return air fan Va (second fan) may be set based on the target pressure of the clean room Rs. Note that the air volume setting of the fan controlled at a constant speed may be performed by the control device 60, or may be performed based on a user's operation via an input means (not shown). To give a specific example, when controlling the supply air fan Ua at a constant speed, the controller 60 sets the supply air fan Ua to have a larger air volume the higher the target pressure of the clean room Rs. Also, when controlling the return air fan Va at a constant speed, the controller 60 sets the return air fan Va to have a smaller air volume the higher the target pressure of the clean room Rs. This makes it easier to bring the room pressure closer to the target pressure when the clean room Rs is used as a positive pressure room or negative pressure room.

[0077] In each embodiment, when the clean room Rs (see FIG. 4) is used as a positive pressure room, the controller 60 drives the supply air fan Ua at a constant speed while setting the return air fan Va to a variable speed based on the room pressure, but this is not limited to the above. That is, depending on the conditions of use, when the clean room Rs is used as a positive pressure room, it may be better to drive the supply air fan Ua at a variable speed based on the room pressure while setting the return air fan Va to a constant speed.

[0078] In each embodiment, when the clean room Rs (see FIG. 4) is used as a negative pressure room, the controller 60 drives the supply air fan Ua at a variable speed based on the room pressure while driving the return air fan Va at a constant speed, but this is not limited to the above. That is, depending on the conditions of use, when the clean room Rs is used as a negative pressure room, it may be better to drive the supply air fan Ua at a constant speed while driving the return air fan Va at a variable speed based on the room pressure.

[0079] Also, the first embodiment and the second embodiment can be appropriately combined. For example, instead of the return air fan Va (see FIG. 4) described in the second embodiment, a return air fan (not shown) that exhausts and returns air from the clean room Rs (see FIG. 4) may be provided. In this way, when the return air fan (second fan) exhausts and returns air from the clean room Rs, the suction side of the supply air fan (first fan) and the suction side of the return air fan (second fan) are each connected to the space (common space) of the large room Ro. This allows a part of the clean air in the clean room Rs to be returned to the space of the large room Ro while the remaining air is exhausted. Also, in the above-mentioned configuration, the supply air fan (first fan) and the return air fan (second fan) may be switchable between one controlled based on the detection value of the pressure sensor 30s and one controlled at a constant speed. This allows the clean room Rs to be selectively used as a positive pressure room or a negative pressure room.

[0080] Alternatively, for example, an exhaust fan (not shown) that exhausts air from the clean room Rs may be provided in place of the return air fan Va described in the second embodiment. In such a configuration, the supply air fan (first fan) and the exhaust fan (second fan) may be switchable between one that is controlled based on the detection value of the pressure sensor 30s and one that is controlled at a constant speed. This allows the clean room Rs to be selectively used as a positive pressure room or a negative pressure room.

[0081] In addition, in each embodiment, the air conditioning system S, SA is used in a regenerative medicine facility as an example, but the present invention is not limited to this. That is, the embodiments can be applied to various other fields such as industrial product manufacturing, food industry, and pharmaceutical manufacturing.

[0082] In addition, each embodiment has been described in detail to clearly explain the present invention, and is not necessarily limited to having all of the configurations described. In addition, it is possible to add, delete, or replace part of the configuration of an embodiment with other configurations. Furthermore, the above-mentioned mechanisms and configurations are those considered necessary for the explanation, and do not necessarily show all mechanisms and configurations of the product. [Explanation of symbols]

[0083] U , W Fan filter unit (first unit) V , Z Fan filter unit (second unit) U a,Wa Intake fan (first fan) Ub, Wb filter (first filter) V a,Za Return air fan (second fan) 13a, 18a, 22a Exhaust fan hmm 3 0s,30t pressure sensor 50 Air Handling Unit 60 Control device (control unit) C Chan B AL1,AL2 Aero nine DS7, DS8 duct shaft F4, F5 filter unit R1 Detachable room R2 1st changing room R3 Pre-processing room R4,R5,R8,R9,R11 front room R6 2nd changing room R7 preparation room R10 Undressing room Rs,Rt Clean Room Ro Large room ( Designated room ) S,SA Air Conditioning System

Claims

1. The air conditioner includes a first unit having a first fan that supplies air to a clean room provided inside a predetermined room, and a first filter that is provided on the blowing side of the first fan, A second unit having a second fan for returning air from the clean room; A duct shaft that guides air from the clean room to the predetermined room; A pressure sensor provided in the clean room; a control unit that controls one of the first fan and the second fan based on the detection value of the pressure sensor and controls the other fan at a constant speed, The predetermined room is a space formed by a side wall, a ceiling, and a floor surface, the clean room is provided so as to be surrounded by the side walls, the ceiling, and the floor of the specific room in a vertical cross-sectional view, the duct shaft extends in a vertical direction along a side surface of the clean room, and an upper end of the duct shaft is open, The air introduced into the clean room via the first fan is returned to the specified room via the second fan and the duct shaft in sequence, an air conditioning system, wherein one of the first fan and the second fan is switchable between being controlled based on the detection value of the pressure sensor and being controlled at a constant speed;

2. A filter unit is provided on the ceiling of the specified room, The height position of the first unit is lower than the height position of the filter unit.

2. The air conditioning system according to claim 1 .

3. The specified room is supplied with air whose temperature has been adjusted by an air handling unit.

2. The air conditioning system according to claim 1 .

4. The control unit is capable of switching the room pressure of the clean room from one of positive pressure and negative pressure to the other.

2. The air conditioning system according to claim 1 .

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