JP2022136712A - Air flow control system and air flow control method of clean room - Google Patents

Abstract

To provide an air flow control system and an air flow control method of a clean room capable of realizing both of reduction of contamination risk and energy-saving.SOLUTION: An air supply device conditions and purifies air recycled from the inside of a room and air taken from the external, and supplies the conditioned and purified air into the room. An exhaust device exhausts the air from the inside of the room to the external while keeping a room pressure at a positive pressure. In a cell processing step to perform cell processing in a safety cabinet, the air supply device and the exhaust device are operated in a first operation mode. In a transition step to transit from the cell processing step to a cell cultivating step to perform a cell cultivation in an incubator, the air supply device and the exhaust device are operated in a second operation mode in which an exhaust air volume from the clean room is larger than an exhaust air volume in the first operation mode. In the cell cultivating step, the air supply device and the exhaust device are operated in a third operation mode in which a supply air volume to the clean room is smaller than a supply air volume in the first operation mode.SELECTED DRAWING: Figure 3

Description

The present invention relates to an air volume control system and an air volume control method for a clean room in which a safety cabinet used for processing cells and an incubator for culturing cells are installed.

In the clean room where cells are processed and cultured, a safety cabinet is installed as a barrier device to prevent contamination with other organisms such as other cells and bacteria during sample cell processing and unintended processing of samples. is used. Cells processed in a safety cabinet are cultured in an incubator. Incubators are often installed in the same clean room where safety cabinets are installed. When the processed cells are stored in an incubator, they are often stored after vibrating the incubator in order to mix the cells and the culture solution more uniformly.

In a clean room, there are various sources of contamination that impair the cleanliness of the clean room. Incubator is one of them. An incubator is a device that maintains a constant temperature and humidity environment for culturing cells. Sometimes I end up An incubator is usually installed exposed in a clean room and is manually opened and closed for use. For this reason, there is a risk that germs and the like that have proliferated inside may spread when the door is opened and closed. In addition, vibrations applied to the incubator and dust generation due to storage operation in the incubator can also be one of the sources of contamination of the clean room.

Ventilation in cleanrooms is important to reduce the risk of contamination from these sources. As a simple ventilation method that can reduce the risk of contamination, it is conceivable to increase the air volume of exhaust air from the clean room as much as possible and introduce outside air accordingly. However, if the amount of exhaust air is simply increased, the room air that has been temperature-controlled is exhausted, and a large amount of energy is used to control the temperature of the outside air, resulting in an increase in energy consumption.

Also, considering the comfort of workers working in the clean room, the air supplied to the clean room must be sufficiently conditioned. Workers' perspiration can also be one of the sources of contamination that contaminates the clean room, so providing a comfortable environment for workers through air conditioning also includes the purpose of reducing the risk of contamination. If the clean room is ventilated by simply increasing the amount of exhaust air, the amount of energy used for air conditioning will increase.

Reducing the amount of energy used, that is, saving energy is one of the important requirements for clean rooms along with reducing the risk of contamination. However, no technology has been proposed at least by the time of filing of this application, which can realize both energy saving and reduction of contamination risk in a clean room. For example, in Patent Document 1, there is a circulation air conditioning operation in which outside air is supplied while air is circulated to the air conditioning room, a full outside air operation in which only outside air is supplied to the air conditioning room, and a switch to switch from all outside air operation to circulation air conditioning operation. An invention relating to an air conditioning operation mode changing system that performs operation is disclosed. However, this invention is an invention aimed at preventing large fluctuations in the indoor air pressure in the air-conditioned room during switching operation from all-outside-air operation to circulation operation, and is intended to save energy and reduce the risk of contamination in clean rooms. Both are not realized.

In addition to Patent Document 1, for example, Patent Documents 2 to 5 can be listed as prior art documents that can be used as a reference for knowing the technical level at the time of filing of the present application. However, like Patent Literature 1, Patent Literatures 2 to 5 do not disclose a technique capable of realizing both energy saving and reduction of contamination risk in a clean room.

Japanese Patent No. 6214383 Japanese Patent No. 6402028 JP-A-2005-328726 Japanese Patent No. 6531810 JP 2001-355885 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide an air volume control system and an air volume control method for a clean room that can achieve both energy saving and reduction of contamination risk. do.

A clean room air volume control system according to the present invention is an air volume control system for a clean room in which a safety cabinet used for processing cells and an incubator for culturing cells are installed. A clean room air volume control system according to the present invention includes an air supply device, an exhaust device, and a control device. The air supply device conditions and purifies the air returned from the clean room through the return air duct and the air taken in from the outside through the outside air duct, and supplies the conditioned and purified air to the clean room through the supply air duct. It is configured to supply air to maintain the chamber pressure at a positive pressure. The exhaust system is configured to exhaust air from the clean room to the outside through an exhaust duct while maintaining the room pressure of the clean room at a positive pressure. The controller is configured to control operation of the air supply system and operation of the exhaust system.

The work process in the clean room includes a cell processing step in which cell processing is performed in a safety cabinet, a cell culturing step in which cell culture is performed in an incubator, and a transition step from the cell processing step to the cell culturing step. The controller operates the air supply device and the exhaust device in the first operation mode in the cell processing step, operates the air supply device and the exhaust device in the second operation mode in the transition step, and operates the air supply device in the cell culture step. and the exhaust device are operated in the third operating mode. The second operation mode is an operation mode in which the exhaust air volume from the clean room is larger than the exhaust air volume in the first operation mode. The third operation mode is an operation mode in which the amount of air supplied to the clean room is smaller than that in the first operation mode.

In the cell processing process, workers are required to perform precise work in safety cabinets. According to the air volume control system for a clean room according to the present invention configured as described above, comfortable air conditioning is provided to the worker, thereby suppressing the worker from sweating while working in the safety cabinet. . This reduces the risk of contaminants such as germs adhering to the sample in the safety cabinet. Therefore, excluding the ventilation of the safety cabinet itself, which has its own air supply and exhaust, the amount of exhaust air in the clean room is reduced to the minimum ventilation amount that can maintain positive pressure. The amount of outside air to be mixed can be throttled. As a result, the temperature control energy required to achieve a comfortable temperature control is reduced, and the energy consumption for exhaust gas and the energy consumption associated with air conditioning are suppressed, thereby realizing energy saving.

In the transfer process, contaminants such as dust, germs, and mold are likely to diffuse into the clean room as workers move and the incubator opens and closes. According to the air volume control system for a clean room according to the present invention configured as described above, when the cell processing process is shifted to the transition process, the operation mode is switched to the second operation mode, and the exhaust air volume is increased. Contamination risk is reduced.

In the cell culture process, the culture is left to the incubator and the operator goes out of the clean room. In other words, air conditioning from the viewpoint of operator's comfort is no longer necessary in the cell culture process. According to the air volume control system for a clean room according to the present invention configured as described above, when shifting from the transition process to the cell culture process, the operation mode is switched to the third operation mode, the air supply air volume is reduced, and the air volume is reduced. Energy saving is achieved by changing the air temperature setting in the direction of not consuming energy.

In the second operation mode, the control device may operate the air supply device and the exhaust device so as to maintain the amount of air supplied to the clean room at the amount of air supplied in the first operation mode. According to this, the comfort of the worker who is performing the transfer work can be maintained.

In the third operation mode, the control device may operate the air supply device and the exhaust device so that the amount of exhaust air from the clean room is smaller than that in the second operation mode. The cell culture process after the incubator has been placed in the incubator results in less contaminant diffusion compared to the transfer process. Therefore, even if the amount of exhaust air is reduced, the risk of contamination can be suppressed, and by reducing the amount of exhaust air, energy can be saved.

The exhaust system may include an exhaust fan and a room pressure control damper provided upstream of the exhaust fan and operating to maintain a positive pressure in the clean room. The exhaust fan is a fan capable of exhausting the exhaust air volume from the first operation mode to the third operation mode. The air supply device may include an air supply fan-incorporated air conditioner and an air supply side constant air volume device provided downstream of the air conditioner in the air supply duct. The control device may be configured to output the set air volume to the air supply side constant air volume device, output the exhaust set air volume to the exhaust fan, and output the control output to the room pressure control damper according to the room pressure measurement value. good. According to this, it is possible to easily switch the operation mode while stably maintaining the room pressure of the clean room at a positive pressure.

The exhaust system may include a first fan and a room pressure control damper provided upstream of the first fan and operating to maintain a positive pressure in the clean room in the exhaust duct. The first fan is a fan capable of discharging a first exhaust air volume. Further, the exhaust device may include a second fan and a constant air volume device provided upstream of the second fan in the sub-exhaust duct. The second fan is a fan capable of discharging a second exhaust air volume larger than the first exhaust air volume, and the sub-exhaust duct is a duct branched from the exhaust duct upstream of the room pressure control damper. When the exhaust system is configured in this way, the control device stops the second fan in the first operating mode, operates the second fan in the second operating mode, and stops the second fan again in the third operating mode. You can drive like you do. According to this, it is possible to change the exhaust air volume for each process by the constant air volume device while maintaining the room pressure of the clean room at a positive pressure by the room pressure control damper. As the constant air volume device, it is desirable to select a device with 1 to 2 W (watts) closed.

Further, when the exhaust device is configured as described above, the control device may control the constant air volume device so that the exhaust air volume of the second fan gradually increases from zero to the second exhaust air volume in the second operation mode. good. According to this, it is possible to suppress the influence of the change in the exhaust air volume on the room pressure of the clean room.

In the clean room air volume control system according to the present invention, a process control terminal may be installed in the clean room. In this case, the control device may switch from the first operation mode to the second operation mode when the completion of the cell processing step is confirmed at the process control terminal. According to this, it is possible to change the operation mode while confirming the completion of the cell processing step. Switching from the second operation mode to the third operation mode may be performed when the start of the cell culture process is confirmed at the process control terminal, or the operation time in the second operation mode has reached a predetermined time. Sometimes it may be switched automatically.

In the clean room air volume control system according to the present invention, a foot switch may be installed in the clean room. In this case, the control device may perform switching from the first operating mode to the second operating mode when the operation of the foot switch is detected. According to this, the operator can change the operation mode without using hands. Switching from the second operation mode to the third operation mode may be performed when the operation of the foot switch is detected again, or may be automatically performed when the operation time in the second operation mode reaches a predetermined time. may be switched.

The clean room may be equipped with an automatic vibrator that vibrates the processed cells. In this case, the control device may perform switching from the first operating mode to the second operating mode when the operating contact of the automatic vibration device is turned on. According to this, it is possible to automatically change the operation mode when a situation in which contamination is likely to occur occurs. Switching from the second operation mode to the third operation mode may be performed when the start of cell culture by the incubator is detected, or when the operation time in the second operation mode reaches a predetermined time. It may be switched automatically.

The clean room air volume control method according to the present invention is applied to a clean room in which a safety cabinet used for cell processing and an incubator for culturing cells are installed in the room, and an air supply device and an exhaust device are provided. The air supply device is a device that conditions and purifies the air that is returned from the clean room and the air that is taken in from the outside, and supplies the conditioned and purified air to the clean room. The exhaust system is a device that exhausts air from the clean room to the outside while maintaining the room pressure of the clean room at a positive pressure.

In the clean room air volume control method according to the present invention, the air supply device and the exhaust device are operated in the first operation mode in the cell processing step, and the air supply device and the exhaust device are operated in the second operation mode in the transition step. In the cell culture step, the air volume control method operates the air supply device and the exhaust device in the third operation mode. The second operation mode makes the exhaust air volume from the clean room larger than the exhaust air volume in the first operation mode, and the third operation mode makes the air supply air volume to the clean room smaller than the air supply air volume in the first operation mode. do.

According to the clean room air volume control method according to the present invention, which is executed as described above, when the cell processing step is shifted to the transition step, the operation mode is switched to the second operation mode, and the exhaust air volume is increased. Contamination risk is reduced. In addition, the amount of exhaust air is increased after moving to the transition process, and the amount of exhaust air in the cell processing process is kept relatively low. It is suppressed, and energy saving is also realized. Furthermore, when shifting from the transition process to the cell culture process, the operation mode is switched to the third operation mode, and the amount of supplied air is reduced, thereby realizing energy saving.

As described above, according to the clean room air volume control system and air volume control method according to the present invention, the risk of contamination is reduced by increasing the exhaust air volume when the cell processing process is shifted to the transition process. In addition, the amount of exhaust air is increased after moving to the transition process, and the amount of exhaust air in the cell processing process is kept relatively low. It is suppressed, and energy saving is also realized. Furthermore, energy saving is realized by reducing the amount of supplied air when shifting from the transfer process to the cell culture process. That is, according to the air volume control system and the air volume control method for a clean room according to the present invention, both energy saving and reduction of contamination risk can be realized.

It is a figure showing composition of an air volume control system concerning a 1st embodiment of the present invention. 4 is a flow chart of air volume control according to the first embodiment of the present invention. 4 is a time chart of air volume control according to the first embodiment of the present invention; It is a figure which shows the structure of the exhaust device which concerns on 2nd Embodiment of this invention. 9 is a time chart of exhaust air volume control according to the second embodiment of the present invention; It is a figure which shows the modification of a structure of an air supply apparatus.

Embodiments of the present invention will be described below with reference to the drawings. However, when referring to numbers such as the number, quantity, amount, range, etc. of each element in the embodiments shown below, unless otherwise specified or clearly specified by the number in principle, the reference The number is not intended to limit the invention. Also, the structures and the like described in the embodiments shown below are not necessarily essential to the present invention unless otherwise specified or clearly specified in principle. In each figure, the same or corresponding parts are denoted by the same reference numerals, and redundant description thereof will be appropriately simplified or omitted.

1. First Embodiment 1-1. Configuration of Air Volume Control System FIG. 1 is a diagram showing the configuration of an air volume control system 100 according to the first embodiment of the present invention. The air volume control system 100 is applied, for example, to the clean room 2 of a bio-system facility involving cell culture. In the clean room 2, a safety cabinet 4 used for processing cells and an incubator 6 for culturing cells are installed. Although not shown, the clean room 2 may be equipped with an automatic vibration device that uniformly mixes the cells and the culture solution by vibrating the incubator.

The ceiling of the clean room 2 is provided with an air supply port 12 for supplying air that has been air-conditioned and purified. A side wall of the clean room 2 is provided with a return air port 22 for taking out recirculated air and an exhaust port 32 for taking out air to be exhausted. However, FIG. 1 is only a schematic diagram, and the positional relationship between the air supply port 12, the return air port 22, and the exhaust port 32 is not limited to the positional relationship shown in FIG. In some cases, the port 32 is installed as the same suction port, and an exhaust duct is branched from a return air duct, which will be described later. Also, the positional relationship between the safety cabinet 4 and the incubator 6 and the air supply port 12, the positional relationship between the safety cabinet 4 and the incubator 6 and the return air port 22, and the positional relationship between the safety cabinet 4 and the incubator 6 and the exhaust port 32 The positional relationship is not limited to that shown in FIG.

The air volume control system 100 includes an air supply device 110 . The air supply device 110 has a supply air duct 10 for supplying air into the clean room 2, a return air duct 20 for returning the air inside the clean room 2, and an outside air duct 40 for introducing outside air. Air supply duct 10 is connected to air supply port 12 . A return air duct 20 extends from the return air port 22 and is connected to the supply air duct 10 . The outside air duct 40 extends from the outside air intake 42 and is connected to the supply air duct 10 . That is, the air supply duct 10 takes in the air recirculated from the clean room 2 and the air taken in from the outside.

The air supply device 110 includes an outside air return air processing air conditioner (AHU) 18 for air conditioning the clean room 2 and a constant air volume device (CAV) 16 for controlling the supply air volume of the conditioned air. prepared for. AHU 18 includes a temperature regulator, a humidity regulator, a blower, and a filter. CAV 16 is installed downstream of air supply duct 10 from AHU 18 . The air supply device 110 also includes a high-performance filter 14 downstream of the air supply duct 10 from the CAV 16 , more specifically, in the vicinity of the air supply port 12 . Air supplied to the clean room 2 is purified by a high efficiency filter 14 . In other words, the clean room 2 is supplied with air that has been air-conditioned and purified to a proper temperature and humidity by the air supply device 110 . Incidentally, the CAV 16 can also be changed to a variable air volume device (VAV).

The air volume control system 100 includes an exhaust device 120 . The exhaust device 120 has an exhaust duct 30 for exhausting the air inside the clean room 2 . Exhaust duct 30 extends from exhaust port 32 and is connected to room air outlet 34 . The exhaust device 120 includes a room pressure control damper (PCD) 36 and an exhaust fan 38 for controlling the room pressure of the clean room 2 . The PCD 36 is installed upstream of the exhaust duct 30 from the exhaust fan 38 . A signal from a room pressure sensor 56 installed in the clean room 2 is input to the PCD 36 via a control device 50 (to be described later) or directly. The PCD 36 operates to maintain the room pressure of the clean room 2 at a constant positive pressure with respect to the reference point pressure (reference pressure) outside the room. That is, the exhaust device 120 is configured to exhaust air from the clean room 2 to the outside while maintaining the room pressure of the clean room 2 at a constant positive pressure.

The air volume control system 100 includes a control device 50 . Controller 50 includes processor 52 and memory 54 . The memory 54 stores a program for operating the air volume control system 100 and temporarily stores signals from various sensors including the room pressure sensor 56 . Processor 52 controls the operation of air supply device 110 and the operation of exhaust device 120 according to programs stored in memory 54 .

A signal from the tablet terminal 8 and a signal from the foot switch 9 are input to the control device 50 . The tablet terminal 8 is a process control terminal for managing work processes in the clean room 2 . The tablet terminal 8 is installed near the safety cabinet 4, for example. The worker uses the tablet terminal 8 to check the completion and start of the process. A foot switch 9 is installed at the operator's feet under the safety cabinet 4 . A footswitch 9 can also be used to check for process completion and initiation. However, it is not always necessary to install both the tablet terminal 8 and the foot switch 9, and either one may be installed.

1-2. Air Volume Control in Air Volume Control System Next, air volume control in the air volume control system 100 configured as described above will be described with reference to FIGS. 2 and 3. FIG. In the air volume control, the controller 50 controls the operation of the air supply device 110 and the exhaust device 120 so as to achieve a desired air volume state.

FIG. 2 is a flowchart of air volume control according to this embodiment. The flowchart represents the procedure of the clean room air volume control method according to the present embodiment. In this embodiment, air volume control is performed in conjunction with the work process in the clean room 2 . The working process in the clean room 2 is divided into a cell processing process, a transfer process, and a cell culturing process. In the cell processing step, cell processing, which is an aseptic operation, is performed in the safety cabinet 4 . In the transition process, aseptic operation is not performed, but work is performed to transition from the cell processing process to the cell culture process. In the cell culture process, cell culture is performed in the incubator 6, although aseptic operation and work are not performed.

Here, VSA is the air supply volume that is the volume of air supplied to the clean room 2, _VEA is the exhaust volume that is the volume of air that is _exhausted from the clean room 2, and the air is extracted from the clean room 2 and returned to the clean room 2 again. The return air volume, which is the volume of air that flows through the air, is denoted as _VRA . Also, the room volume of the clean room ₂ is expressed as v0. The room volume v ₀ is a fixed value determined from the size of the clean room 2 . Here, as an example, the room volume v0 of the clean room ₂ is assumed to be 30 m3.

In the cell processing step, which is the first work step, the control device 50 controls the operation of the air supply device 110 and the operation of the exhaust device 120 in the first operation mode. In the first operation mode, the control device 50 controls the OAC 18 and CAV 16 of the air supply device 110 so that the air supply air volume _VSA is set to the air volume corresponding to the set ventilation frequency _RSA1 . In addition, in the first operation mode, the control device 50 controls the exhaust fan 38 of the exhaust device 120 so that the exhaust air volume _{VEA is equal to the set ventilation frequency REA1 .} However, since the PCD 36 operates to maintain the room pressure at a constant positive pressure, the actual exhaust air volume fluctuates with respect to the air volume for the set ventilation frequency _REA1 . The difference between the supply air volume _VSA and the exhaust air volume _VEA is the return air volume _VRA . The relationship between the supply air volume _{VSA, the return air volume VRA ,} and the exhaust air volume _VEA in the first operation mode can be expressed by the following equations.
V _SA = v ₀ ×R _SA1
V _EA =v ₀ ×R _EA1
V _RA = V _SA - V _EA

An example of the set ventilation frequency _RSA1 for the supply air volume in the first operation mode is 30 times per hour, and an example of the set ventilation frequency _REA1 for the exhaust air volume is 2 times per hour. Using these values, a specific example of each air volume in the first operation mode is calculated as follows.
VSA = _30m3 x 30 times/hr = 900m3/hr
V _EA = 30 m3 x 2 times/hr = 60 m3/hr
VRA = _900m3 /hr - 60m3/hr = 840m3/hr

As shown by the above air volumes, in the cell processing process, priority is given to the comfort of the workers working in the clean room 2, and the return air volume V _RA is increased. As a result, the amount of exhaust air is kept relatively low, so the amount of energy used for exhaust is suppressed. In addition, as a result of reducing the amount of exhaust air, the amount of outside air taken in from the outside air duct 40 is also reduced, so the amount of energy used for conditioning the outside air to a suitable temperature and humidity is also reduced. That is, in the first operation mode, it is possible to realize energy saving while creating a comfortable working environment for the worker. Note that each of the above numerical values is merely an example, and other numerical values can be used. For example, considering both comfort and energy saving, the set ventilation frequency _RSA1 for the supply air volume is preferably about 20 to 40 times, and the set ventilation frequency R _EA1 for the exhaust air volume is preferably About 1 to 3 times.

In the next transition step, control device 50 controls the operation of air supply device 110 and the operation of exhaust device 120 in the second operating mode. The control device 50 executes switching from the first operating mode to the second operating mode based on a signal from the tablet terminal 8 . Specifically, when the operator touches the tablet terminal 8 to check the completion of the cell processing step, the control device 50 switches from the first operation mode to the second operation mode. That is, the operation mode is changed while confirming the completion of the cell processing step.

In the second operation mode, the control device 50 controls the AHU 18 and CAV 16 of the air supply device 110 so that the air supply air volume _VSA is set to the air volume for the set ventilation number _RSA2 . As an example, the amount of supplied air in the second operation mode is maintained at the amount of supplied air in the first operation mode. Also, in the second operation mode, the control device 50 controls the exhaust fan 38 of the exhaust device 120 so as to increase the exhaust air volume _{VEA to the predetermined air volume VEA_SHIFT for} the transition process. However, since the PCD 36 operates to maintain the room pressure at a constant positive pressure, the actual exhaust air volume fluctuates with respect to the predetermined air volume _{VEA_SHIFT} . The difference between the supply air volume _VSA and the exhaust air volume _VEA is the return air volume _VRA . The relationship between the supply air volume _{VSA, the return air volume VRA ,} and the exhaust air volume _VEA in the second operation mode can be expressed by the following equations.
V _SA = v ₀ ×R _SA2
V _EA =V _{EA_SHIFT}
V _RA = V _SA - V _EA

An example of the set ventilation frequency _{RSA2 for the supplied air volume in the second operation mode is 30 times per hour, the same as the set ventilation frequency RSA1 for} the supplied air volume in the first operation mode. An example of the predetermined air volume _{VEA_SHIFT} exhausted in the second operation mode is 600 m3/hr. This corresponds to an exhaust air volume of 20 times at the set ventilation frequency. Using these values, a specific example of each air volume in the second operation mode is calculated as follows.
VSA = _30m3 x 30 times/hr = 900m3/hr
VEA = _600m3 /hr
V _RA =900m3/hr-600m3/hr=300m3/hr

As shown by the above airflows, the transition step increases the exhaust airflow V _EA by as much as 10 times that of the cell processing step. In the transfer process, contaminants such as dust, _germs , and mold tend to diffuse into the clean room 2 as workers move and the incubator 6 opens and closes. be done. In addition, in the transition process, the amount of supplied air is maintained at the amount of supplied air in the cell processing process, so the comfort of the operator performing the transition work can be maintained. Note that each of the above numerical values is merely an example, and other numerical values can be used. For example, considering both comfort and pollution risk reduction, the set ventilation frequency _{RSA2 for the air supply air volume is preferably about 20 to 40 times, and the predetermined air volume VEA_SHIFT is} the exhaust gas in the first operation mode. It is about 5 to 15 times the air volume.

In the cell culture process, which is the final work process, the control device 50 controls the operation of the air supply device 110 and the operation of the exhaust device 120 in the third operation mode. The control device 50 executes switching from the second operating mode to the third operating mode based on a signal from the tablet terminal 8 . Specifically, when the operator touches the tablet terminal 8 to check the start of the cell culture process, the control device 50 switches from the second operation mode to the third operation mode. That is, the operation mode is changed while confirming the start of the cell culture process.

In the third operation mode, the control device 50 controls the AHU 18 and CAV 16 of the air supply device 110 so that the air supply air volume _VSA is equal to the air volume of the set ventilation number _RSA3 . The set ventilation frequency _RSA3 is smaller than the set ventilation frequency _RSA1 for the supply air volume in the first operation mode, and the supply air volume in the third operation mode is kept lower than the supply air volume in the first operation mode. In addition, in the third operation mode, the control device 50 controls the exhaust fan 38 of the exhaust device 120 so that the exhaust air volume _{VEA becomes the air volume for the set ventilation frequency REA3 .} As an example, the exhaust air volume in the third operating mode is returned to the exhaust air volume in the first operating mode. However, since the PCD 36 operates to maintain the room pressure at a constant positive pressure, the actual exhaust air volume fluctuates with respect to the air volume for the set ventilation frequency _REA3 . The difference between the supply air volume _VSA and the exhaust air volume _VEA is the return air volume _VRA . The relationship between the supply air volume _{VSA, the return air volume VRA ,} and the exhaust air volume _VEA in the third operation mode can be expressed by the following equations.
V _SA = v ₀ ×R _SA3
V _EA =v ₀ ×R _EA3
V _RA = V _SA - V _EA

An example of the set ventilation frequency _RSA3 for the supply air volume in the third operation mode is half the set ventilation frequency _RSA1 for the supply air volume in the first operation mode, ie, 15 times per hour. An example of the set ventilation frequency _REA3 for the exhaust air volume in the third operation mode is twice per hour, the same as the set ventilation frequency _REA1 for the exhaust air volume in the first operation mode. Using these values, a specific example of each air volume in the third operation mode is calculated as follows.
VSA = _30m3 x 15 times/hr = 450m3/hr
V _EA = 30 m3 x 2 times/hr = 60 m3/hr
VRA = _450m3 /hr - 60m3/hr = 390m3/hr

As shown by the above air volumes, in the cell culturing process, the supplied air volume _VSA is reduced to about half of that in the cell culturing process and the transfer process. In the cell culture process, culture is entrusted to the incubator 6, and the workers go out of the clean room 2. Therefore, air conditioning is not used for the comfort of the workers, but for the purpose of removing the heat emitted from the equipment including the incubator 6. is air-conditioned. Therefore, as described above, the air supply volume _VSA can be reduced compared to the cell culture process, etc., and energy saving can be realized. In addition, in the cell culture process after the incubator is stored in the incubator 6, since the operator is already out of the clean room 2, the diffusion of contaminants is less than in the transfer process. Therefore, even if the exhaust air volume _VEA is reduced, the pollution risk can be suppressed, and by reducing the exhaust air volume _VEA , energy saving can be realized. Note that each of the above numerical values is merely an example, and other numerical values can be used. For example, considering both energy saving and reduction of pollution risk, the set ventilation frequency _RSA3 for the supply air volume is preferably about 10 to 20 times, and the set ventilation frequency _REA3 for the exhaust air volume is preferably is about 1 to 3 times.

FIG. 3 is a time chart of air volume control according to this embodiment. FIG. 3 shows changes in room pressure P _IN , supply air volume V _SA , exhaust air volume V _EA , and return air volume V _RA depending on the work process.

As shown in this time chart, room pressure control is also performed in the air volume control according to the present embodiment. By operating the PCD 36 according to the signal from the room pressure sensor 56, the room pressure P _IN is maintained at a constant pressure higher than the outdoor pressure P _OUT , that is, a positive pressure, in all the steps. The outdoor pressure P _OUT is, for example, the atmospheric pressure.

The air supply air volume _VSA is maintained at a large air volume from the cell processing step to the transition step, and is reduced to about half in the cell culturing step. The exhaust air volume V _EA is low in the cell processing process, increased in the transition process, and reduced again in the cell culture process to the same air volume as in the cell processing process. The return air volume _VRA is the difference between the supply air volume _VSA and the exhaust air volume _VEA , and the air volume is large in the cell processing process, but is suppressed to be low in the cell processing process and the cell culturing process. By performing such air volume control, both energy saving and reduction of contamination risk can be realized as described above.

It should be noted that the change in the exhaust air volume _VEA when the cell processing process is shifted to the transition process is preferably a gradual increase as indicated by the dotted line in FIG. 3 rather than a rapid increase as indicated by the solid line in FIG. The air volume of the outside air introduced by the air volume control system 100 is determined by the difference between the air supply air volume and the return air volume of the fan built into the AHU if there is no outside air fan. Further, the room pressure is determined by each resistance between the exhaust duct and the return air duct generated by each static pressure of the exhaust fan and the fan built in the AHU. Therefore, when the exhaust air volume _VEA is rapidly increased, there is a possibility that the room pressure _PIN of the clean room 2 becomes a negative pressure because the introduction of outside air cannot catch up. By gradually increasing the exhaust air volume _VEA , the intake of the outside air can catch up with the exhaust, so that the room pressure _PIN can be easily maintained at a positive pressure.

2. Second Embodiment 2-1. Configuration of Exhaust System The second embodiment of the present invention is characterized by the configuration of the exhaust system, and other configurations are common to those of the first embodiment. FIG. 4 is a diagram showing the configuration of the exhaust device 122 according to this embodiment.

The exhaust device 122 has an exhaust duct 30 for exhausting the air inside the clean room 2 . Exhaust duct 30 extends from exhaust port 32 and is connected to room air outlet 34 . A PCD 36 for controlling the room pressure of the clean room 2 and an exhaust fan 38 are installed in the exhaust duct 30 as in the first embodiment. The exhaust fan 38 corresponds to the first fan described in claim 4 . In this embodiment, the controller 50 causes the exhaust fan 38 to operate steadily. Therefore, the exhaust air volume of the exhaust fan 38 is set to a constant air volume (first exhaust air volume) in all the working steps of the cell processing process, the transfer process, and the cell culturing process. In other words, the control device 50 operates the exhaust fan 38 with a constant exhaust air volume in all of the first, second, and third operation modes.

The exhaust device 122 has a secondary exhaust duct 60 branched from the exhaust duct 30 upstream of the PCD 36 and connected to an indoor air outlet 62 . A CAV 64 and an exhaust fan 66 are installed in the sub-exhaust duct 60 . The CAV 64 is installed upstream of the sub-exhaust duct 60 from the exhaust fan 66 . The exhaust fan 66 corresponds to the second fan recited in claim 4 . The controller 50 operates the exhaust fan 66 only in the transition process, that is, in the second operating mode, and stops the exhaust fan 66 in the first and third operating modes. The exhaust air volume of the exhaust fan 66 during operation is set to a large air volume (second exhaust air volume) so as to obtain the required exhaust air volume in the transition process. When switching from the first operation mode to the second operation mode, the control device 50 gradually opens the CAV 64 from the fully closed state to gradually increase the exhaust air volume of the exhaust fan 66 from zero to the second exhaust air volume.

2-2. Exhaust Air Volume Control by Exhaust Device Next, exhaust air volume control by the exhaust device 122 configured as described above will be described with reference to FIG.

FIG. 5 is a time chart of exhaust air volume control according to the present embodiment. In FIG. 5, the dotted line indicates the amount of exhaust air _VEA1 that passes through the PCD 36 and is exhausted from the exhaust fan 38, and the broken line indicates the amount of exhaust air _VEA2 that passes through the CAV 64 and is exhausted from the exhaust fan 66. In FIG. 5, the solid line indicates the exhaust air volume _VEA exhausted from the clean room 2. As shown in FIG.

An example of the exhaust air volume V _EA1 in the cell processing step, that is, in the first operation mode is the exhaust volume for two ventilation times per hour, as in the first embodiment. Assuming that the volume of the clean room 2 is 30 m3 as in the first embodiment, the exhaust air volume _VEA1 is 60 m3/hr. Since the exhaust fan 38 is operated at a constant air volume as described above, the exhaust air volume V _EA1 of 60 m3/hr in the first operation mode is maintained in the transition step, that is, in the second operation mode. Furthermore, although omitted in the time chart, the exhaust air volume _VEA1 of 60 m3/hr in the first operation mode is maintained even in the cell culture process, that is, in the third operation mode.

In the cell processing step, that is, in the first operation mode, the exhaust air volume _VEA2 is zero because the exhaust fan 66 is stopped. In the transition process, that is, when the operation mode is switched to the second operation mode, the operation of the exhaust fan 66 causes the exhaust air volume _VEA2 to increase. However, as the CAV 64 is gradually opened from fully closed to a predetermined opening, the exhaust air volume _VEA2 gradually increases. The exhaust air volume _VEA2 when the CAV 64 is opened to a predetermined opening is, for example, 540 m3/hr. Thereafter, the fixed air volume is maintained while the exhaust fan 66 is operated by the CAV 64, which is a constant air volume device. As a result, the total air volume of the exhaust air volume _VEA1 and the exhaust air volume _VEA2 , that is, the exhaust air volume _VEA discharged from the clean room 2 gradually increases from 60 m3/hr to 600 m3/hr.

The gradual increase period of the exhaust air volume _VEA2 is 5 to 10 minutes. If the exhaust air volume _VEA is _rapidly increased, the introduction of outside air may not catch up and the room pressure _PIN of the clean room 2 may become a negative pressure. By doing so, it becomes easier to maintain the room pressure _PIN at a positive pressure. In particular, in this embodiment, the PCD 36 and the exhaust fan 38 can be exclusively used for room pressure control by assigning the CAV 64 and the exhaust fan 66 to increase the amount of exhaust air. Therefore, according to the present embodiment, it is possible to further suppress the influence of changes in the exhaust air volume on the room pressure of the clean room 2 .

3. Other Embodiments Modifications of the above embodiment will be described below. First, FIG. 6 is a diagram showing a modification of the configuration of the air supply device. The variant shown in FIG. 6 has a PCD 70 installed in the outside air duct 40 . Alternatively, the CAV 72 may be provided in the outside air duct 40 instead of the PCD 70 . By providing the PCD 70 or the CAV 72 in the outside air duct 40, it is possible to suppress the influence of changes in atmospheric pressure on the amount of supplied air.

The control device 50 may switch from the first operation mode to the second operation mode when the operation of the foot switch 9 is detected. According to this, the operator can change the operation mode without using hands. Moreover, when the operation of the foot switch 9 is detected again, the switching from the second operation mode to the third operation mode may be executed.

If an automatic vibration device is installed in the clean room 2, the control device 50 may perform switching from the first operation mode to the second operation mode when the operation contact of the automatic vibration device is turned on. According to this, it is possible to automatically change the operation mode when a situation in which contamination is likely to occur occurs. Also, when the start of cell culture by the incubator 6 is detected, the second operation mode may be switched to the third operation mode. In addition, it is also possible to switch the operation mode using the open/close contact of the door or the start/stop contact of the related equipment.

A timer may be used for switching from the second operating mode to the third operating mode. Specifically, the control device 50 may automatically switch from the second operation mode to the third operation mode when the operation time in the second operation mode reaches a predetermined time.

2: Clean room 4: Safety cabinet 6: Incubator 8: Tablet terminal (process control terminal)
9: Foot switch 10: Supply air duct 12: Air supply port 14: High performance filter 16: Constant air volume device 18: Outside air return air processing air conditioner 20: Return air duct 22: Return air port 30: Exhaust duct 32: Exhaust port 36: Room pressure control damper 38: Exhaust fan 40: Outside air duct 50: Control device 52: Processor 54: Memory 56: Room pressure sensor 60: Sub-exhaust duct 64: Constant air volume device 66: Exhaust fan 70: Room pressure control damper 72 : Constant air volume device 100: Air volume control system 110: Air supply device 120: Exhaust device 122: Exhaust device

Claims (10)

An air volume control system for a clean room in which a safety cabinet used for processing cells and an incubator for culturing the cells are installed,
Air recirculated from the clean room through the return air duct and air taken in from the outside through the outside air duct are conditioned and purified, and the conditioned and purified air is supplied to the clean room through the supply air duct. an air supply device;
an exhaust device that exhausts air from the clean room to the outside through an exhaust duct while maintaining the room pressure of the clean room at a positive pressure;
a control device for controlling the operation of the air supply device and the operation of the exhaust device;
The control device is
In the cell processing step in which cell processing is performed in the safety cabinet, the air supply device and the exhaust device are operated in the first operation mode,
In the transition step of transitioning from the cell processing step to the cell culturing step of culturing cells in the incubator, the air is supplied in the second operation mode in which the exhaust air volume from the clean room is larger than the exhaust air volume in the first operation mode. operating the device and the exhaust device;
A clean room characterized in that, in the cell culturing step, the air supply device and the exhaust device are operated in a third operation mode in which the amount of air supplied to the clean room is smaller than the amount of air supplied in the first operation mode. air volume control system. The control device is
2. In the second operation mode, the air supply device and the exhaust device are operated so as to maintain the amount of air supplied to the clean room at the amount of air supplied in the first operation mode. The clean room air volume control system described in . The control device is
2. The air supply device and the exhaust device are operated in the third operation mode so that the amount of exhaust air from the clean room is smaller than that in the second operation mode. 2. The clean room air volume control system according to 2 above. A process control terminal is installed in the clean room,
The control device is
4. The method according to any one of claims 1 to 3, wherein when completion of the cell processing step is confirmed in the process control terminal, switching from the first operation mode to the second operation mode is performed. The described clean room air volume control system. A foot switch is installed in the clean room,
The control device is
4. The clean room air volume control according to any one of claims 1 to 3, wherein switching from the first operation mode to the second operation mode is executed when an operation of the foot switch is detected. system. The clean room is equipped with an automatic vibration device that vibrates the processed cells,
The control device is
4. The clean room according to any one of claims 1 to 3, wherein switching from the first operation mode to the second operation mode is performed when an operation contact of the automatic vibration device is turned on. air volume control system. The exhaust device
an exhaust fan capable of exhausting the exhaust air volume from the first operation mode to the third operation mode;
a room pressure control damper provided upstream of the exhaust fan and operating to maintain the room pressure of the clean room at a positive pressure;
provided in the exhaust duct,
The air supply device
an air conditioner with a built-in air supply fan;
an air supply side constant air volume device provided downstream of the air conditioner;
provided in the air supply duct,
The control device is
Outputting the set air volume to the air supply side constant air volume device,
Outputting the exhaust set air volume to the exhaust fan,
7. The clean room air volume control system according to any one of claims 1 to 6, wherein a control output is output to said room pressure control damper in accordance with a measured room pressure value. The exhaust device
a first fan capable of exhausting a first exhaust air volume;
a room pressure control damper provided upstream of the first fan and operating to maintain the room pressure of the clean room at a positive pressure;
provided in the exhaust duct,
a second fan capable of discharging a second exhaust air volume larger than the first exhaust air volume;
a constant air volume device provided upstream of the second fan;
is provided in a sub-exhaust duct branched from the exhaust duct upstream of the room pressure control damper,
The control device is
stopping the second fan in the first operation mode;
operating the second fan in the second operation mode;
7. The clean room air volume control system according to claim 1, wherein the second fan is stopped in the third operation mode. The control device is
9. The clean room air volume control system according to claim 8, wherein in the second operation mode, the constant air volume device is controlled such that the exhaust air volume of the second fan gradually increases from zero to the second exhaust air volume. A safety cabinet used for cell processing and an incubator for culturing the cells are installed in a room, and the air recirculated from the room and the air taken in from the outside are conditioned and purified, and the air-conditioned and purified air is supplied to the room. An air volume control method for a clean room provided with an air supply device that supplies air to the clean room and an exhaust device that exhausts air from the room to the outside while maintaining the room pressure in the room at a positive pressure,
In the cell processing step in which cell processing is performed in the safety cabinet, the air supply device and the exhaust device are operated in the first operation mode,
In the transition step of transitioning from the cell processing step to the cell culturing step of culturing cells in the incubator, the air is supplied in the second operation mode in which the exhaust air volume from the clean room is larger than the exhaust air volume in the first operation mode. operating the device and the exhaust device;
A clean room characterized in that, in the cell culturing step, the air supply device and the exhaust device are operated in a third operation mode in which the amount of air supplied to the clean room is smaller than the amount of air supplied in the first operation mode. air volume control method.

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