Cleanroom system and control method

Abstract

To prevent humidity in a clean room from decreasing when ventilating the clean room.SOLUTION: A control device 22 acquires a state of air to be blown into a clean room CR. The control device 22 controls a blower 19 according to the acquired air state so that a ventilation amount, which is an amount of air determined based on a cleanliness level in the clean room CR, is changed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a control device, a control method, a control program, and a clean room system.

Background Art

[0002] Patent Document 1 discloses a clean room system that reduces the amount of energy used in a clean room.

[0003] Specifically, the clean room system disclosed in Patent Document 1 is limited to cases where it is necessary to blow air to satisfy either condition, considering both the temperature inside the clean room and the cleanliness inside the clean room, so that the clean room system blows air. According to the clean room system of Patent Document 1, the amount of energy used in the clean room can be reduced as compared with cases where air is constantly blown.

[0004] Also, the clean room system of Patent Document 1 is limited to cases where it is necessary to blow air to satisfy either condition, considering both the humidity inside the clean room and the cleanliness inside the clean room, so that the clean room system blows air. According to the clean room system of Patent Document 1, the amount of energy used in the clean room can be reduced as compared with cases where air is constantly blown.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The cleanroom system described in Patent Document 1 determines whether or not to blow air into the cleanroom depending on the cleanliness level inside the cleanroom. Patent Document 1 also describes the density of particles (particles / m³) inside the cleanroom. 3 ) is defined as cleanliness (for example, paragraphs

[0046] ,

[0070] , and Figure 6), and control is performed such that the higher the cleanliness with a higher particle density in the cleanroom, the greater the amount of air supplied to the cleanroom (for example, Figure 6).

[0007] Here, we define that the lower the particle density in the cleanroom, the higher the cleanliness. Based on this definition of cleanliness, the cleanroom system of Patent Document 1 implements control such that the airflow rate decreases as the cleanliness of the cleanroom increases (for example, Figure 6(B)). Furthermore, the cleanroom system of Patent Document 1 implements control such that the airflow rate decreases as the temperature in the cleanroom decreases (for example, Figure 6(A)).

[0008] Based on these premises, let us consider, for example, a case where the cleanliness of the cleanroom is high and the temperature inside the cleanroom is also relatively high. In such a case, the cleanroom system described in Patent Document 1 is expected to perform control such as not blowing air or reducing the amount of air blown because the cleanliness of the cleanroom is high.

[0009] However, if the temperature inside the cleanroom is relatively high, the air supplied to the cleanroom by the air conditioner is expected to be cooled. In such cases, the air being supplied is dehumidified as it is cooled, and its humidity decreases. Specifically, when the air supplied to the cleanroom is cooled in the cooling unit, condensation occurs in the cooling unit. This removes moisture from the air being supplied, and the humidity of the air being supplied decreases. When such air is supplied to the cleanroom, it lowers the humidity inside the cleanroom.

[0010] Therefore, the clean system described in Patent Document 1 has the problem that when it controls the airflow into the cleanroom based on the cleanliness of the cleanroom, it may reduce the humidity inside the cleanroom.

[0011] This disclosure is made in view of the above circumstances and provides a control device, a control method, a control program, and a cleanroom system that can suppress a decrease in humidity inside a cleanroom when blowing air into the cleanroom. [Means for solving the problem]

[0012] A first aspect of this disclosure is a control device including: an airflow rate determination unit that determines the amount of air to be blown into a cleanroom from an air blower based on the cleanliness of the cleanroom; an acquisition unit that acquires the state of the air being blown into the cleanroom by the air blower; and a control unit that controls the air blower so that the amount of air determined by the airflow rate determination unit is changed according to the state of the air acquired by the acquisition unit. [Effects of the Invention]

[0013] According to this disclosure, when blowing air into a cleanroom, it is possible to suppress the decrease in humidity inside the cleanroom. [Brief explanation of the drawing]

[0014] [Figure 1] This figure shows an example of a schematic configuration of the cleanroom system according to the first embodiment. [Figure 2] This is a psychrometric diagram illustrating the control process of the first embodiment. [Figure 3] This is a diagram illustrating the stepwise control of inverter frequency. [Figure 4] This is a conceptual diagram illustrating inverter frequency control by a control device. [Figure 5]It is a schematic block diagram of a cooperation control device or a computer that functions as a control device. [Figure 6] It is a schematic block diagram showing an example of the functional configuration of the control device of the first embodiment. [Figure 7] It is a diagram showing an example of a control processing routine executed by the control device of the first embodiment. [Figure 8] It is a diagram showing an example of the schematic configuration of the clean room system of the second embodiment. [Figure 9] It is an air diagram for explaining the control process of the second embodiment. [Figure 10] It is a schematic block diagram showing an example of the functional configuration of the control device of the second embodiment. [Figure 11] It is a diagram showing an example of a control processing routine executed by the control device of the second embodiment.

Modes for Carrying Out the Invention

[0015] Hereinafter, embodiments will be described in detail with reference to the drawings.

[0016] <Clean Room System of the First Embodiment> FIG. 1 is a diagram showing a clean room system 10 of the first embodiment. As shown in FIG. 1, the clean room system 10 of the first embodiment includes a particle counter 12 installed in the clean room CR, a temperature sensor 14 installed in the clean room CR, a water channel 16, a chilled water two-way valve 17, an air conditioner 18, a cooperation control device 20, a blow-out temperature sensor 21A, a control device 22A, and an inverter control panel 24.

[0017] The particle counter 12 sequentially measures the cleanliness of the clean room CR. The particle counter 12 is an example of the cleanliness measurement unit of the present disclosure.

[0018] The temperature sensor 14 sequentially measures the temperature in the clean room CR. The temperature sensor 14 is an example of the state measurement unit of the present disclosure.

[0019] Chilled water flows through channel 16. Channel 16 is connected to the cooling coil H of the air conditioner 18, which will be described later, and the chilled water flows from the W1 direction to the W2 direction as shown in Figure 1.

[0020] The chilled water two-way valve 17 adjusts its opening degree according to the temperature inside the cleanroom CR measured by the temperature sensor 14, thereby controlling the amount of chilled water supplied to the cooling coil H of the air conditioner 18. When the temperature inside the cleanroom CR is high, the opening degree of the chilled water two-way valve 17 increases, and the amount of chilled water supplied to the cooling coil H of the air conditioner 18 increases. Conversely, when the temperature inside the cleanroom CR is low, the opening degree of the chilled water two-way valve 17 decreases, and the amount of chilled water supplied to the cooling coil H of the air conditioner 18 decreases. In this way, the temperature of the blown air is adjusted by adjusting the amount of chilled water supplied to the cooling coil H according to the temperature inside the cleanroom CR.

[0021] The air conditioner 18 comprises a cooling coil H, a blower 19 equipped with a motor M, and an inverter control panel 24. The blower 19 of the air conditioner 18 blows air into the clean room CR. Specifically, the rotation speed of the motor M of the air conditioner 18 changes according to the inverter frequency output from the inverter control panel 24, which will be described later, and the amount of air blown from the blower 19 changes. Note that the blower 19 is an example of the blowing unit of this disclosure.

[0022] The linked control device 20 acquires the cleanliness level measured by the particle counter 12. Then, the linked control device 20 determines the airflow rate, which is the amount of air blown into the cleanroom CR by the blower 19, according to the cleanliness level. Specifically, when the cleanliness level inside the cleanroom CR is high, the linked control device 20 outputs a control signal to the control device 22A that reduces the airflow rate into the cleanroom CR. Conversely, when the cleanliness level inside the cleanroom CR is low, the linked control device 20 outputs a control signal to the control device 22A that increases the airflow rate into the cleanroom CR. Specifically, the linked control device 20 outputs an inverter frequency signal to the control device 22A according to the airflow rate into the cleanroom CR. In this embodiment, the cleanliness level is higher when there is less dust inside the cleanroom CR and lower when there is more dust inside the cleanroom CR. Note that the linked control device 20 is an example of the airflow rate determination unit of this disclosure.

[0023] The outlet temperature sensor 21A measures the temperature of the air blown from the air conditioner 18. The outlet temperature sensor 21A then outputs the measured air temperature to the control device 22A.

[0024] The control device 22A acquires the inverter frequency signal output from the linked control device 20. The control device 22A also acquires the temperature of the air blown from the air conditioner 18, which is measured by the outlet temperature sensor 21A. The control device 22A determines the amount of air blown into the clean room CR by changing the inverter frequency signal output from the linked control device 20. Finally, the control device 22A outputs the inverter frequency signal, which is a control signal representing the determined amount of air blown, to the inverter control panel 24.

[0025] The inverter control panel 24 controls the frequency of the inverter frequency signal output to the motor M of the blower 19 of the air conditioner 18, in accordance with the control signal output from the control device 22A.

[0026] The cleanroom CR is equipped with an air intake port IN and an air supply port SU. The air from inside the cleanroom CR that flows into the air intake port IN is cooled or heated by the air conditioner 18 through the duct (piping) P1, and then supplied to the cleanroom CR through the air supply port SU via the duct P2. A dust filter, for example, is installed in either the air intake port IN, the air supply port SU, or the ducts P1 or P2 to capture dust present inside the cleanroom CR. This maintains the cleanliness of the cleanroom CR.

[0027] Various production equipment (not shown) is installed inside the cleanroom (CR). These production devices, or the products they produce, may require predetermined levels of cleanliness, temperature, and humidity. Therefore, the cleanliness of the cleanroom (CR) must be maintained within a specified range. Furthermore, the temperature and humidity of the cleanroom (CR) must also be maintained within a specified range.

[0028] As described above, the two-way chilled water valve 17 adjusts the amount of chilled water supplied to the cooling coil H according to the temperature inside the cleanroom CR. This adjusts the temperature of the air blown from the air conditioner 18, and maintains the temperature inside the cleanroom CR within a predetermined range.

[0029] Furthermore, the linked control device 20 controls the amount of air supplied from the air conditioner 18 based on the cleanliness of the cleanroom CR measured by the particle counter 12. This ensures that the cleanliness of the cleanroom CR is maintained within a predetermined range. For example, the linked control device 20 can be implemented by the clean system described in Patent Document 1 as described above.

[0030] However, as mentioned above, even if the linked control device 20 controls the amount of air supplied from the air conditioner 18 based on the cleanliness of the cleanroom CR, the humidity of the air being supplied may decrease. Specifically, when the air supplied to the cleanroom CR is cooled by the cooling coil H, condensation occurs in the cooling coil H. This removes moisture from the air being supplied, causing the humidity of the air to decrease. When such air is supplied into the cleanroom CR, it lowers the humidity inside the cleanroom CR. As mentioned above, the humidity inside the cleanroom CR needs to be kept within a predetermined range, so if the humidity inside the cleanroom CR decreases, it is necessary to humidify the cleanroom CR, which requires energy.

[0031] Furthermore, for example, the clean system of the second embodiment in Patent Document 1 sequentially detects the humidity inside the cleanroom CR and controls the amount of air supplied from the air conditioner 18 so that the humidity inside the cleanroom CR remains constant. However, such control processing is a reactive control process that occurs after the humidity inside the cleanroom CR has been detected, and if the humidity inside the cleanroom CR has dropped, it is necessary to humidify the inside of the cleanroom CR, which requires energy.

[0032] Therefore, the cleanroom system 10 of the first embodiment controls the amount of air supplied to the cleanroom CR according to the temperature of the air supplied to the cleanroom CR. The temperature of the air supplied to the cleanroom CR is an example of the state of the supplied air.

[0033] If the temperature of the air supplied to the cleanroom CR is low, it can be inferred that the heat load inside the cleanroom CR is high and the room temperature is high. Therefore, if the temperature of the air supplied to the cleanroom CR is low, the airflow rate should be increased. By increasing the airflow rate, it is possible to efficiently lower the temperature inside the cleanroom CR without excessively lowering the temperature of the supplied air. As a result, the temperature of the air supplied to the cleanroom CR rises, and the occurrence of condensation on the cooling coil H is suppressed. Consequently, it is possible to supply air to the cleanroom CR without lowering the humidity of the air supplied. This keeps the humidity inside the cleanroom CR constant.

[0034] Specifically, the cleanroom system 10 of the first embodiment increases the airflow rate as the temperature of the air supplied into the cleanroom CR decreases. Conversely, the cleanroom system 10 of the first embodiment decreases the airflow rate as the temperature of the air supplied into the cleanroom CR increases. This will be explained in detail below.

[0035] Figure 2 is a psychrometric chart illustrating the control process of the first embodiment. In the psychrometric chart of Figure 2, the horizontal axis represents temperature and the vertical axis represents absolute humidity. A relative humidity curve is also drawn on the psychrometric chart of Figure 2. TA shown in Figure 2 represents the indoor conditions of the cleanroom CR. The cleanroom system 10 needs to perform air conditioning control so that the following indoor conditions of the cleanroom CR are met.

[0036] Temperature: 22±3℃ Humidity: 50±10%

[0037] As shown in Figure 2, under conditions where the heat load inside the cleanroom CR is low, the temperature of the air supplied from the air conditioner 18 is expected to be within the range of A1 (e.g., 17°C to 22°C) due to the air temperature control by the chilled water two-way valve 17. Under conditions where the heat load inside the cleanroom CR is neither high nor low, the temperature of the air supplied from the air conditioner 18 is expected to be within the range of A2 (e.g., 15°C to 17°C). On the other hand, under conditions where the heat load inside the cleanroom CR is high, the temperature of the air supplied from the air conditioner 18 is expected to be within the range of A3 (e.g., 11.6°C to 15°C).

[0038] Point P (temperature 15°C, humidity 75%) shown in Figure 2 represents the temperature and humidity at which the air blown from the air conditioner 18 is not dehumidified. In the psychrometric chart shown in Figure 2, as the temperature and humidity of the air blown from the air conditioner 18 change from point P in the direction of arrow D, the moisture contained in the air blown from the air conditioner 18 is dehumidified, and the humidity of the blown air decreases.

[0039] When the above indoor conditions are set, for example, a first temperature threshold of 15°C is set in advance, and a second temperature threshold of 17°C is set in advance.

[0040] If the temperature measured by the outlet temperature sensor 21A is below the first temperature threshold, the control device 22A changes the airflow rate according to the cleanliness level determined by the linked control device 20 and outputs an inverter frequency signal that increases the airflow rate from the air conditioner 18. This prevents the temperature of the air blown from the air conditioner 18 from becoming too low. Furthermore, it prevents a decrease in the humidity of the air blown from the air conditioner 18, thereby preventing a decrease in humidity inside the cleanroom CR.

[0041] On the other hand, if the temperature measured by the outlet temperature sensor 21A is above the second temperature threshold, the control device 22A outputs an inverter frequency signal that reduces the airflow rate according to the cleanliness level determined by the linked control device 20.

[0042] Then, if the temperature measured by the outlet temperature sensor 21A is above the first temperature threshold and below the second temperature threshold, the control device 22A outputs an inverter frequency signal that maintains the current airflow rate.

[0043] Figure 3 is a diagram illustrating the stepwise control of the inverter frequency. As shown in Figure 3, the control device 22A determines the amount of air supplied from the air conditioner 18 by gradually increasing or decreasing the inverter frequency signal according to the indoor load in the clean room CR. Specifically, as indicated by arrow X in Figure 3, the control device 22A gradually increases the inverter frequency when the temperature of the air supplied from the air conditioner 18 falls below 15°C. On the other hand, as indicated by arrow Y in Figure 3, the control device 22A gradually decreases the inverter frequency when the temperature of the air supplied from the air conditioner 18 rises above 17°C.

[0044] Figure 4 is a conceptual diagram illustrating inverter frequency control to satisfy the indoor conditions TA described above. As shown in Figure 4, in step S1, the control device 22A acquires an inverter frequency signal from the linked control device 20. The inverter frequency signal acquired from the linked control device 20 is the inverter frequency required to achieve the airflow rate corresponding to the cleanliness level in the cleanroom CR, that is, the instruction value for the air conditioner 18. Note that the inverter frequency signal acquired from the linked control device 20 is a continuous value, not a step frequency.

[0045] Next, in step S2, the control device 22A compares the current inverter frequency operating the air conditioner 18 with the inverter frequency obtained from the linked control device 20. If the current inverter frequency is greater than the inverter frequency obtained from the linked control device 20, the process proceeds to step S4. On the other hand, if the current inverter frequency is less than or equal to the inverter frequency obtained from the linked control device 20, the process proceeds to step S3. The control device 22A then controls the air conditioner 18 to operate at the inverter frequency obtained from the linked control device 20. This control corresponds to controlling the air conditioner 18 so that the amount of air supplied is determined according to the cleanliness level determined by the linked control device 20.

[0046] The determination process in step S2 above also determines whether the cleanliness of the cleanroom CR meets the required conditions. Specifically, if the inverter frequency obtained from the linked control device 20 is lower than the current inverter frequency, it means that the cleanliness of the cleanroom CR already meets or is in the process of meeting the required conditions. Therefore, if the inverter frequency obtained from the linked control device 20 is lower than the current inverter frequency, it becomes possible to proceed to the subsequent control processes (steps S4 to S10) for maintaining humidity.

[0047] In step S4, the control device 22A determines whether the temperature measured by the outlet temperature sensor 21A is below the first temperature threshold (15°C). If the temperature measured by the outlet temperature sensor 21A is below the first temperature threshold (15°C), the control device 22A increases the frequency step shown by arrow X in Figure 3 by one step in step S5 and controls the air conditioner 18 to operate at the inverter frequency corresponding to that frequency step. On the other hand, if the temperature measured by the outlet temperature sensor 21A is above the first temperature threshold (15°C), the process proceeds to step S6.

[0048] In step S6, the control device 22A determines whether the temperature measured by the outlet temperature sensor 21A is equal to or greater than the second temperature threshold (17°C). If the temperature is equal to or greater than the first temperature threshold (15°C) and less than the second temperature threshold (17°C), the control device 22A controls the air conditioner 18 to continue operating at the current inverter frequency without changing the frequency step shown by arrow X or arrow Y in Figure 3 in step S7. On the other hand, if the temperature measured by the outlet temperature sensor 21A is equal to or greater than the second temperature threshold (17°C), the process proceeds to step S8.

[0049] In step S8, the control device 22A determines whether the inverter frequency signal obtained from the linked control device 20 is greater than the step frequency one level below the current inverter frequency operating the air conditioner 18. If the inverter frequency signal obtained from the linked control device 20 is greater than the step frequency one level below the current inverter frequency operating the air conditioner 18, the control device 22A controls the air conditioner 18 to operate at the inverter frequency obtained from the linked control device 20 in step S9. This control corresponds to controlling the air conditioner 18 so that the amount of air supplied according to the cleanliness level determined by the linked control device 20 is realized. On the other hand, if the inverter frequency signal obtained from the linked control device 20 is less than or equal to the step frequency one level below the current inverter frequency operating the air conditioner 18, the process proceeds to step S10.

[0050] In step S10, the control device 22A reduces the frequency step indicated by arrow Y in Figure 3 by one step and controls the air conditioner 18 to operate at the inverter frequency corresponding to that frequency step. Alternatively, the determination process in step S8 may be omitted, and the system may proceed to step S10 if the determination process in step S6 results in "YES".

[0051] As shown in Figure 3, consider the case where the current inverter frequency is 48Hz and the inverter frequency signal obtained from the linked control device 20 is 46Hz. In this case, the determination process in step S8 determines that the inverter frequency signal (46Hz) obtained from the linked control device 20 is greater than the step frequency (40Hz) one step below the current inverter frequency (48Hz), so the process proceeds to step S9, and the air conditioner 18 is operated using the inverter frequency signal (46Hz) obtained from the linked control device 20. This control process is based on the understanding that the inverter frequency signal (46Hz) obtained from the linked control device 20 is less than the current inverter frequency (48Hz), and although the cleanliness of the clean room CR already meets or is meeting the requirements, it is not yet very high, so the air conditioner 18 is operated using the inverter frequency signal (46Hz) obtained from the linked control device 20.

[0052] The interoperation control device 20 and the control device 22A are implemented, for example, by a PLC (Programmable Logic Controller). Alternatively, for example, the interoperation control device 20 and the control device 22A can be implemented by the computer 50 shown in Figure 5. The computer 50 includes a CPU 51, a memory 52 as a temporary storage area, and a non-volatile storage unit 53. The computer 50 also includes an input / output interface (I / F) 54 to which input / output devices, etc. (not shown) are connected, and a read / write (R / W) unit 55 that controls the reading and writing of data to the recording medium. The computer 50 also includes a network interface (I / F) 56 that is connected to a network such as the Internet. The CPU 51, memory 52, storage unit 53, input / output I / F 54, R / W unit 55, and network I / F 56 are connected to each other via a bus 57.

[0053] The storage unit 53 can be implemented using a hard disk drive (HDD), solid state drive (SSD), flash memory, etc. The storage unit 53, as a storage medium, stores a program that allows the computer 50 to function. The CPU 51 reads the program from the storage unit 53, loads it into memory 52, and sequentially executes the processes contained in the program.

[0054] Furthermore, the functions implemented by the program can also be implemented using semiconductor integrated circuits, or more specifically, Application Specific Integrated Circuits (ASICs).

[0055] Figure 6 is a diagram illustrating an example of the functional configuration of the control device 22A. As shown in Figure 6, the control device 22A comprises an acquisition unit 30A and a control unit 32A.

[0056] The acquisition unit 30A acquires the temperature, which is an example of the state of the air being blown into the cleanroom CR by the blower 19.

[0057] The control unit 32A controls the blower 19 so that the airflow rate, which is the amount of air determined based on the cleanliness level in the cleanroom CR, is changed according to the air temperature acquired by the acquisition unit 30A.

[0058] Specifically, as described above, the control unit 32A controls the blower 19 of the air conditioner 18 such that the airflow rate increases as the temperature of the air blown from the air conditioner 18 decreases, and the airflow rate decreases as the temperature of the air increases.

[0059] More specifically, the control unit 32A controls the blower 19 to increase the airflow rate when the temperature of the air blown from the air conditioner 18 is below a first temperature threshold. The control unit 32A also controls the blower 19 to decrease the airflow rate when the temperature of the air blown from the air conditioner 18 is above a second temperature threshold. Furthermore, the control unit 32A controls the blower 19 so that the airflow rate does not change when the temperature of the air blown from the air conditioner 18 is above the first temperature threshold but below the second temperature threshold. Specifically, the control unit 32A controls the blower 19 so that the current airflow rate is maintained when the temperature of the air blown from the air conditioner 18 is above the first temperature threshold but below the second temperature threshold.

[0060] Furthermore, in actual control, when the control unit 32A increases the amount of air supplied to the cleanroom CR, it increases the frequency of the inverter frequency signal output to the motor M of the blower 19 of the air conditioner 18. On the other hand, when the control unit 32A decreases the amount of air supplied to the cleanroom CR, it decreases the frequency of the inverter frequency signal output to the motor M of the blower 19 of the air conditioner 18.

[0061] <Operation of the cleanroom system 10 in the first embodiment> Next, the operation of the cleanroom system 10 of the first embodiment will be described. When the particle counter 12 of the cleanroom system 10 starts measuring the cleanliness of the cleanroom CR, and the temperature sensor 14 starts measuring the temperature of the cleanroom CR, the air conditioner 18 starts blowing air into the cleanroom CR. Then, the linked control device 20 starts outputting a control signal corresponding to the cleanliness measured by the particle counter 12. Then, the control device 22A executes the control processing routine shown in Figure 7.

[0062] In step S200, the control device 22A acquires a control signal output from the linked control device 20, which represents the airflow rate according to the cleanliness level. This control signal represents the airflow rate according to the cleanliness level inside the cleanroom CR, and is actually represented by a continuous value of the inverter frequency.

[0063] In step S202, the control device 22A controls the outlet temperature sensor 21A Obtain the air temperature measured by [the device / system].

[0064] In step S204, the control device 22A determines whether the temperature obtained in step S202 is less than the first temperature threshold. If the temperature is less than the first temperature threshold, the process proceeds to step S206. If the temperature is equal to or greater than the first temperature threshold, the process proceeds to step S208.

[0065] In step S206, the control device 22A outputs a control signal to the inverter control panel 24 that increases the amount of air blown from the air conditioner 18. Specifically, the control device 22A sets a new inverter frequency signal by increasing the step frequency as described above, and outputs a control signal representing that inverter frequency signal to the inverter control panel 24. The inverter control panel 24 controls the motor M of the blower 19 of the air conditioner 18 in accordance with the inverter frequency signal output from the control device 22A.

[0066] In step S208, the control device 22A determines whether the temperature obtained in step S202 is equal to or greater than the second temperature threshold. If the temperature is equal to or greater than the first temperature threshold and less than the second temperature threshold, the process proceeds to step S210. On the other hand, if the temperature is equal to or greater than the second temperature threshold, the process proceeds to step S212.

[0067] In step S210, the control device 22A outputs a control signal to the inverter control panel 24 that maintains the current airflow rate. The inverter control panel 24 controls the motor M of the blower 19 of the air conditioner 18 according to the inverter frequency signal output from the control device 22A.

[0068] In step S212, the control device 22A outputs a control signal to the inverter control panel 24 that reduces the amount of air blown from the air conditioner 18. Specifically, the control device 22A sets a new inverter frequency signal by reducing the step frequency as described above, and outputs a control signal representing that inverter frequency signal to the inverter control panel 24. The inverter control panel 24 controls the motor M of the blower 19 of the air conditioner 18 in accordance with the inverter frequency signal output from the control device 22A.

[0069] As described above, the control device 22A according to the first embodiment acquires the temperature of the air supplied to the cleanroom CR. The control device 22A then controls the blower 19 so that the amount of air supplied, which is the amount of air determined based on the cleanliness level in the cleanroom CR, is changed according to the acquired air temperature. This makes it possible to suppress a decrease in humidity inside the cleanroom when supplying air to the cleanroom.

[0070] Specifically, the control device 22A controls the blower 19 such that the airflow rate increases as the temperature of the blown air decreases, and decreases as the temperature of the blown air increases. This prevents the temperature of the air blown from the air conditioner 18 from dropping excessively, and suppresses the occurrence of condensation on the cooling coil H. As a result, it becomes possible to blow air into the cleanroom CR without reducing the humidity of the air being blown into the cleanroom CR.

[0071] Furthermore, the temperature of the air blown by the blower 19 is adjusted according to the temperature inside the cleanroom CR, and the control device 22A controls the blower 19 so that the airflow rate is changed according to the air temperature while the air temperature is being adjusted. This makes it possible to suppress a decrease in humidity inside the cleanroom CR.

[0072] <Cleanroom system of the second embodiment> Next, a second embodiment will be described. The second embodiment differs from the first embodiment in that the amount of air supplied is changed according to the humidity of the air supplied to the cleanroom CR. Components similar to those in the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0073] Figure 8 shows a cleanroom system 210 of the second embodiment. As shown in Figure 8, the cleanroom system 210 of the first embodiment includes a particle counter 12 installed inside the cleanroom CR, a temperature sensor 14 installed inside the cleanroom CR, a water channel 16, a chilled water two-way valve 17, an air conditioner 18, a linkage control device 20, a discharge humidity sensor 21B, a control device 22B, and an inverter control panel 24.

[0074] Figure 9 is a psychrometric chart illustrating the control process of the second embodiment. Similar to Figure 2, TA shown in Figure 9 represents the indoor conditions of the cleanroom CR.

[0075] As shown in Figure 9, the control device 22B reduces the amount of air supplied from the air conditioner 18 if the humidity of the air supplied from the air conditioner 18 is within the range of B1 (for example, humidity 50% to 65%).

[0076] Furthermore, if the humidity of the air blown from the air conditioner 18 is within the range of B2 (for example, humidity of 65% to 75%), the control device 22B maintains the airflow rate from the air conditioner 18 without changing it.

[0077] Furthermore, the control device 22B increases the airflow rate from the air conditioner 18 if the humidity of the air blown from the air conditioner 18 is within the range of B3 (for example, humidity of 75% to 90%).

[0078] This control process makes it possible to suppress a decrease in humidity inside the cleanroom CR when blowing air into the cleanroom, similar to the first embodiment.

[0079] Figure 10 is a diagram showing an example of the functional configuration of the control device 22B. As shown in Figure 10, the control device 22B of the second embodiment comprises an acquisition unit 30B and a control unit 32B.

[0080] The acquisition unit 30B of the second embodiment acquires humidity, which is an example of the state of the air being blown into the cleanroom CR.

[0081] In the second embodiment, the control unit 32B controls the blower 19 so that the amount of air supplied, determined based on the cleanliness level in the cleanroom CR, is changed according to the humidity of the air acquired by the acquisition unit 30B.

[0082] Specifically, as described above, 32B controls the blower 19 of the air conditioner 18 such that the airflow rate decreases as the humidity of the air blown from the air conditioner 18 decreases, and the airflow rate increases as the humidity of the air increases.

[0083] More specifically, 32B reduces the airflow rate if the humidity of the air supplied from the air conditioner 18 is below a first humidity threshold (e.g., 65%). Furthermore, 32B increases the airflow rate if the humidity of the air supplied from the air conditioner 18 is above a second humidity threshold (e.g., 75%). Additionally, 234 controls the fan 19 to maintain the current airflow rate if the humidity of the air supplied from the air conditioner 18 is above the first humidity threshold but below the second humidity threshold.

[0084] Furthermore, in actual control, when the control unit 32B increases the amount of air supplied to the cleanroom CR, it increases the frequency of the inverter frequency signal output to the motor M of the blower 19 of the air conditioner 18. On the other hand, when the control unit 32B decreases the amount of air supplied to the cleanroom CR, it decreases the frequency of the inverter frequency signal output to the motor M of the blower 19 of the air conditioner 18.

[0085] <Operation of the cleanroom system 210 in the second embodiment> Next, the operation of the cleanroom system 210 of the second embodiment will be described. When the particle counter 12 of the cleanroom system 210 starts measuring the cleanliness of the cleanroom CR, and the temperature sensor 14 starts measuring the temperature of the cleanroom CR, the air conditioner 18 starts blowing air into the cleanroom CR. Then, the linked control device 20 starts outputting a control signal corresponding to the cleanliness measured by the particle counter 12. Then, the control device 22B executes the control processing routine shown in Figure 10.

[0086] In step S200, the control device 22B acquires a control signal output from the linked control device 20, which represents the amount of air blown according to the cleanliness level.

[0087] In step S302, the control device 22B acquires the humidity of the air measured by the outlet humidity sensor 21B.

[0088] In step S304, the control device 22B determines whether the humidity obtained in step S302 is less than the first humidity threshold. If the humidity is less than the first humidity threshold, the process proceeds to step S306. If the humidity is equal to or greater than the first humidity threshold, the process proceeds to step S308.

[0089] In step S206, the control device 22B outputs a control signal to the inverter control panel 24 that reduces the amount of air blown from the air conditioner 18. Specifically, the control device 22B sets a new inverter frequency signal by reducing the step frequency as described above, and outputs a control signal representing that inverter frequency signal to the inverter control panel 24. The inverter control panel 24 controls the motor M of the blower 19 of the air conditioner 18 according to the inverter frequency signal output from the control device 22B.

[0090] In step S308, the control device 22B determines whether the humidity obtained in step S302 is equal to or greater than the second humidity threshold. If the humidity is equal to or greater than the first humidity threshold and less than the second humidity threshold, the process proceeds to step S310. On the other hand, if the humidity is equal to or greater than the second humidity threshold, the process proceeds to step S312.

[0091] In step S310, the control device 22B outputs a control signal to the inverter control panel 24 that maintains the current airflow rate. The inverter control panel 24 controls the motor M of the blower 19 of the air conditioner 18 in accordance with the inverter frequency signal output from the control device 22B.

[0092] In step S312, the control device 22B outputs a control signal to the inverter control panel 24 that increases the amount of air blown from the air conditioner 18. Specifically, the control device 22B sets a new inverter frequency signal by increasing the step frequency as described above, and outputs a control signal representing that inverter frequency signal to the inverter control panel 24. The inverter control panel 24 controls the motor M of the blower 19 of the air conditioner 18 according to the inverter frequency signal output from the control device 22B.

[0093] As explained above, the control device 22B according to the second embodiment acquires the humidity of the air supplied to the cleanroom CR. The control device 22B then processes the acquired air humidity Accordingly, the blower 19 is controlled so that the airflow rate, which is the amount of air determined based on the cleanliness level inside the cleanroom CR, is changed. This makes it possible to suppress a decrease in humidity inside the cleanroom when blowing air into the cleanroom.

[0094] This disclosure is not limited to the embodiments described above, and various modifications and applications are possible without departing from the spirit of the invention. Modifications are described below.

[0095] [Example 1] In the embodiments described above, the case in which each threshold is fixed was used as an example, but the invention is not limited to this. For example, each threshold may be changed according to the current date information and the current time information. For example, the control unit 32A of the first embodiment acquires at least one of the current date information and the current time information, and changes at least one of the first temperature threshold and the second temperature threshold according to at least one of the current date information and the current time information. Also, for example, the control unit 32B of the second embodiment changes at least one of the first humidity threshold and the second humidity threshold according to at least one of the current date information and the current time information. This makes it possible to perform, for example, seasonal control and time of day control.

[0096] [Differentiation 2] In the embodiments described above, the amount of air supplied to the cleanroom CR is controlled according to the temperature and cleanliness of the cleanroom CR and the temperature or humidity of the air supplied to the cleanroom CR, but the invention is not limited to this. For example, the amount of air supplied to the cleanroom CR may be controlled according to the indoor operating conditions that represent the operating status of the cleanroom (for example, the entry and exit of people into the cleanroom CR, the operating status of production equipment (not shown), or the timing of the production equipment (not shown) from shutdown to startup). In this case, the control unit 32 acquires the indoor operating conditions that represent the operating status of the cleanroom CR and determines the amount of air supplied to the cleanroom CR according to the temperature or humidity of the air and the indoor operating conditions.

[0097] [Difference 3] In the embodiments described above, the example described was that there is only one particle counter 12 and one temperature sensor 14, but the invention is not limited to this. For example, multiple particle counters 12 and temperature sensors 14 may be installed in the cleanroom CR. In this case, the amount of air supplied to the cleanroom CR may be determined according to the cleanliness of multiple locations or the temperature of multiple locations within the cleanroom CR. For example, the average, minimum, or maximum value of the values ​​from multiple locations may be used.

[0098] [Differentiation Example 4] In the embodiments described above, the linked control device 20 determines the airflow rate according to the cleanliness level, and the control device 22 changes the airflow rate according to the temperature or humidity of the air being supplied, but the invention is not limited to this. For example, the control device 22 may determine the airflow rate to the cleanroom CR according to the cleanliness level of the cleanroom CR and the temperature or humidity of the air being supplied. In this case, the control device 22 may, after determining the airflow rate according to the cleanliness level, change the airflow rate according to the temperature or humidity of the air being supplied. Specifically in this case, the control device 22, as the airflow rate determination unit, determines the airflow rate of the air supplied from the blower 19 based on the cleanliness level of the cleanroom CR. Then, the control device 22 changes the airflow rate according to the cleanliness level according to the temperature or humidity of the air being supplied. Alternatively, the control device 22 may determine the airflow rate according to a combination of the cleanliness level and the temperature or humidity of the air being supplied.

[0099] Furthermore, although the above embodiment described the case where the air condition is temperature or humidity as an example, the air condition also includes temperature, humidity, dew point temperature, wet bulb temperature, and absolute humidity, etc. Therefore, the control unit 32 may perform control based on air conditions other than temperature and humidity.

[0100] Furthermore, although this specification describes an embodiment in which the program is pre-installed, it is also possible to provide the program by storing it on a computer-readable recording medium. For example, the program may be provided in a form stored on a non-transitory storage medium such as a CD-ROM (Compact Disk Read Only Memory), DVD-ROM (Digital Versatile Disk Read Only Memory), or USB (Universal Serial Bus) memory. Alternatively, the program may be provided in a form that can be downloaded from an external device via a network.

[0101] In the above embodiment, the processing that the CPU reads and executes software (programs) may be executed by various processors other than the CPU. Examples of such processors include PLDs (Programmable Logic Devices) such as FPGAs (Field-Programmable Gate Arrays) whose circuit configuration can be changed after manufacturing, and dedicated electrical circuits that are processors with circuit configurations specifically designed to execute specific processing, such as ASICs (Application Specific Integrated Circuits). Alternatively, a GPGPU (General-purpose graphics processing Unit) may be used as the processor. Furthermore, each processing may be executed by one of these various processors, or by a combination of two or more processors of the same or different types (for example, multiple FPGAs, and a combination of a CPU and an FPGA). More specifically, the hardware structure of these various processors is an electrical circuit that combines circuit elements such as semiconductor elements.

[0102] Furthermore, each process in this embodiment may be configured by a computer or server equipped with a general-purpose processing unit and storage device, and each process may be executed by a program. This program is stored in the storage device and can be recorded on a recording medium such as a magnetic disk, optical disk, or semiconductor memory, or provided over a network. Of course, none of the other components have to be implemented by a single computer or server; they may be implemented in a distributed manner across multiple computers connected by a network.

[0103] All documents, patent applications, and technical standards described herein are incorporated by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually noted to be incorporated by reference.

[0104] In the embodiments described above, please note that unless the word "only" is used, such as "based only on XX," "according only to XX," or "in the case of XX only," it is assumed in this specification that additional information may also be considered. For example, the statement "do b in the case of a" does not necessarily mean "always do b in the case of a" unless explicitly stated otherwise.

[0105] Furthermore, even if there are aspects of a method, program, terminal, device, server, or system (hereinafter referred to as "method, etc.") that perform operations different from those described herein, each aspect of the disclosed technology is intended to cover the same operations as any of those described herein, and the existence of operations different from those described herein does not mean that such method, etc. is outside the scope of each aspect of the disclosed technology.

[0106] The following additional information is disclosed regarding the embodiments described above.

[0107] (Note 1) An airflow rate determination unit determines the amount of air to be blown into the cleanroom from the air blower based on the cleanliness level of the cleanroom, An acquisition unit that acquires the state of the air being blown into the cleanroom by the aforementioned blowing unit, A control unit controls the air blowing unit so that the air blowing amount determined by the air blowing amount determination unit is changed according to the air condition acquired by the acquisition unit, A control device including a control device. (Note 2) The aforementioned state of the air is the temperature of the air, The control unit controls the air blowing unit such that the amount of air blown increases as the air temperature decreases and decreases as the air temperature increases. The control device described in Appendix 1. (Note 3) The control unit, If the temperature of the air is below a first temperature threshold, the air blower is controlled to increase the amount of air blown. If the temperature of the air is above a second temperature threshold, the air blower is controlled to reduce the amount of air blown. If the temperature of the air is above the first temperature threshold and below the second temperature threshold, the air blower is controlled so that the airflow rate is not changed. The control device described in Appendix 2. (Note 4) The control unit acquires at least one of the current date information and the current time information, and modifies at least one of the first temperature threshold and the second temperature threshold according to at least one of the current date information and the current time information. The control device described in Appendix 3. (Note 5) The aforementioned state of the air is the humidity of the air. The control unit controls the air blowing unit such that the air volume decreases as the humidity of the air decreases and increases as the humidity of the air increases. The control device described in Appendix 1. (Note 6) The control unit, If the humidity of the air is less than a first humidity threshold, the air blower is controlled to reduce the amount of air blown. If the humidity of the air is equal to or greater than a second humidity threshold, the air blower is controlled to increase the airflow rate. If the humidity of the air is equal to or greater than the first humidity threshold and less than the second humidity threshold, the air blower is controlled so that the airflow rate is not changed. The control device described in Appendix 5. (Note 7) The control unit acquires at least one of the current date information and the current time information, and modifies at least one of the first humidity threshold and the second humidity threshold according to at least one of the current date information and the current time information. The control device described in Appendix 6. (Note 8) The temperature of the air blown by the blower is adjusted according to the temperature inside the cleanroom. The control unit controls the air blower so that the amount of air blown is changed according to the state of the air while the temperature of the air is being adjusted. A control device as described in any one of the appendices 1 to 7. (Note 9) The control unit, The indoor operating status, which represents the operating status inside the cleanroom, is obtained. The airflow rate determination unit determines the airflow rate according to the air condition and the room operating conditions. A control device as described in any one of the appendices 1 to 8. (Note 10) The control unit, By increasing the frequency of the inverter frequency signal output to the motor of the blower unit, the amount of air blown is increased. By reducing the frequency of the inverter frequency signal output to the motor of the blower unit, the amount of air blown is reduced. A control device as described in any one of the appendices 1 to 9. (Note 11) The airflow rate determination unit determines the airflow rate according to the cleanliness of multiple locations within the cleanroom. A control device as described in any one of the appendices 1 to 10. (Note 12) Based on the cleanliness level inside the cleanroom, the amount of air to be blown into the cleanroom from the air blower is determined. The state of the air supplied to the cleanroom by the blower is acquired. The air blower is controlled so that the determined airflow rate is changed according to the acquired air condition. A program that causes a computer to perform a process. (Note 13) Based on the cleanliness level inside the cleanroom, the amount of air to be blown into the cleanroom from the air blower is determined. The state of the air supplied to the cleanroom by the blower is acquired. The air blower is controlled so that the determined airflow rate is changed according to the acquired air condition. A program that causes a computer to perform a process. (Note 14) A control device as described in any one of the appendices 1 to 11, a cleanliness measuring unit for measuring the cleanliness of the cleanroom, an air blowing unit for blowing air into the cleanroom, and a condition measuring unit for measuring the state of the air blown into the cleanroom. A cleanroom system including a cleanroom system. [Explanation of Symbols]

[0108] 10,210 Cleanroom Systems 12 Particle Counters 14. Temperature sensor 17 Cold water two-way valve 18 Air conditioner 19 Blower 20. Cooperative control device 21A Temperature Sensor 21B Humidity Sensor 22 Control device 24 Inverter control panel 50 Computers

Claims

1. An air conditioner that conditioned the air discharged from the cleanroom through an air intake installed in the cleanroom, and supplied the conditioned air to the cleanroom through an air supply installed in the cleanroom, A unit that determines the amount of air to be supplied to the cleanroom from the air conditioner based on the cleanliness level of the cleanroom, In a cleanroom system equipped with, A unit for acquiring the temperature of the air blown into the air intake by the air conditioner, If the air temperature acquired by the acquisition unit is below the first temperature threshold, the control unit controls the air conditioner so that the airflow rate determined by the airflow rate determination unit increases. A cleanroom system characterized by having the following features.

2. The control unit, If the air temperature acquired by the acquisition unit is greater than or equal to a second temperature threshold which is greater than the first temperature threshold, the air conditioner is controlled to reduce the airflow rate. The cleanroom system according to feature 1.

3. The control unit acquires at least one of the current date information and the current time information, and modifies at least one of the first temperature threshold and the second temperature threshold according to at least one of the current date information and the current time information. The cleanroom system according to feature 2.

4. An air conditioner that conditioned the air discharged from the cleanroom through an air intake installed in the cleanroom, and supplied the conditioned air to the cleanroom through an air supply installed in the cleanroom, A unit that determines the amount of air to be supplied to the cleanroom from the air conditioner based on the cleanliness level of the cleanroom, In a cleanroom system equipped with, A unit for acquiring the humidity of the air blown into the air intake by the air conditioner, If the humidity of the air acquired by the acquisition unit is equal to or greater than the second humidity threshold, the control unit controls the air conditioner so that the airflow rate determined by the airflow rate determination unit increases. A cleanroom system characterized by having the following features.

5. The control unit, If the humidity of the air acquired by the acquisition unit is less than the first humidity threshold which is less than the second humidity threshold, the air conditioner is controlled to reduce the airflow rate. The cleanroom system according to feature 4.

6. The control unit acquires at least one of the current date information and the current time information, and modifies at least one of the first humidity threshold and the second humidity threshold according to at least one of the current date information and the current time information. The cleanroom system according to claim 5, characterized in that it is the same as described in claim 5.

7. The control unit, The indoor operating status, which represents the operating status inside the cleanroom, is obtained. The airflow rate determination unit determines the airflow rate according to the air temperature and the operating conditions of the room. A cleanroom system according to any one of claims 1 to 3.

8. The control unit, By increasing the frequency of the inverter frequency signal output to the motor of the air conditioner, the amount of air blown is increased. By reducing the frequency of the inverter frequency signal output to the motor of the air conditioner, the amount of air blown can be reduced. A cleanroom system according to any one of claims 1 to 6.

9. The airflow rate determination unit determines the airflow rate according to the cleanliness of multiple locations within the cleanroom. A cleanroom system according to any one of claims 1 to 6.

10. A method for controlling a cleanroom, comprising an air conditioner that conditioned the air discharged from the cleanroom through an air intake installed in the cleanroom, and supplied the conditioned air to the cleanroom through an air supply installed in the cleanroom, Based on the cleanliness of the cleanroom, the amount of air supplied to the cleanroom from the air conditioner is determined. The temperature of the air blown into the air intake by the air conditioner is obtained. If the acquired air temperature is below a first temperature threshold, the air conditioner is controlled to increase the determined airflow rate. Control method.

11. A method for controlling a cleanroom, comprising an air conditioner that conditioned the air discharged from the cleanroom through an air intake installed in the cleanroom, and supplied the conditioned air to the cleanroom through an air supply installed in the cleanroom, Based on the cleanliness of the cleanroom, the amount of air supplied to the cleanroom from the air conditioner is determined. The humidity of the air blown into the air intake by the air conditioner is obtained. If the acquired humidity of the air is equal to or greater than the second humidity threshold, the air conditioner is controlled to increase the determined airflow rate. Control method.

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