JP2002106939A - Air conditioning system - Google Patents

Abstract

(57) [Problem] To provide an air conditioning system capable of easily performing calibration, obtaining a stable air volume, and inexpensively constructing a system capable of switching to a non-operation mode. SOLUTION: In an air conditioning system 71, an air conditioner 31 provided with a blower fan 41 capable of changing a blowing amount, an air supply duct 53 connecting the air conditioner 41 and clean rooms 45a to 45c, and an air conditioner 31 provided inside the air conditioner 31 First HEPA filter 4 through which the air sent to the air supply duct 53 passes
9, a second HEPA filter 57 provided near the air outlets of the clean rooms 45a to 45c and through which air supplied from the air supply duct 53 passes, and blown out from the air outlet 55 provided near the second HEPA filter. Volume damper 59 for variably adjusting the amount of conditioned air, and air supply duct 5
3 and a supply-side airflow sensor 61 that detects the amount of conditioned air passing through the air supply duct 53 and uses this detection signal as a signal for controlling the airflow of the blower fan 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioning system suitable for use in a clean room (for example, a factory of a pharmaceutical factory) which needs to maintain temperature, humidity, indoor air pressure and cleanliness according to management standards. .

[0002]

2. Description of the Related Art For example, in a pharmaceutical factory, a plurality of clean rooms (hereinafter, referred to as "work rooms") are provided continuously according to a pharmaceutical process. Conventionally, the management of temperature, humidity, indoor air pressure and cleanliness in such a factory room is performed by a variable air volume single duct system (VAV: Variable Air Volum) or a constant air volume single duct system (CAV: Constant Air Volume). It was generally done.

That is, as shown in FIG. 2, the supply side of an air conditioner 11 in which a filter 1, a cooling unit 3, a heating unit 5, a humidifying spray 7, and a blower fan 9 are sequentially arranged in the blower direction. , An air supply duct 13 is connected. The air supply duct 13 is provided in each of the processing rooms 15a, 15
Pipes b and 15c are connected to VAV units 17a, 17b and 17c provided corresponding to the respective working rooms. The outlet sides of the VAV units 17a, 17b, and 17c are connected to the respective processing rooms 15a, 15b, and 15c via HEPA filters 19a, 19b, and 19c. A return duct 21 is provided in each of the processing rooms 15a, 15b, 15c.
a, 21b, 21c are connected, and the return duct 21
a, 21b and 21c are integrally connected to the return side of the air conditioner 11.

The VAV units 17a, 17b, and 17c are connected to an indoor temperature thermostat TH. The VAV units 17a, 17b, and 17c adjust the air volume of the air sent from the air conditioner 11 while keeping the air temperature constant. It operates so as to change in response to a change in load. On the other hand, on the exhaust side, the chamber pressure is monitored by the pressure sensor 23, and the exhaust damper 25 is detected based on the detection value from the pressure sensor 23.
The differential pressure is controlled by adjusting the opening / closing degree of the motor or by controlling an exhaust fan (not shown) with an inverter. In the conventional example shown in FIG. 2, the case where only the VAV system is used has been described as an example. However, this type of air-conditioning system may be used when only the CAV system is used or when the VAV system and the CAV system are mixed. is there.

[0005]

However, the above-mentioned conventional air conditioning system has the following problems. That is, for example, when installing a VAV unit, it is desirable to provide a fixed amount of straight pipe ducts from the characteristics of the device. However, in the case of a factory in a pharmaceutical factory, since relatively small rooms are continuous, a space for installing a straight pipe duct cannot be secured, and the performance of the VAV unit may not be fully exhibited. In addition, each workshop has HE
A PA filter is provided. The resistance of the HEPA filter increases when dust contained in the air blown from the air conditioner is clogged. As the resistance of the HEPA filter increases, the amount of air supplied to the factory room decreases. In such a case, VA
By operating the V unit and increasing the amount of air supplied to the HEPA filter, a predetermined air volume according to the management standard is secured. That is, the air volume adjustment for the clogging of the HEPA filter has been one of the major reasons why the VAV unit has to be provided. And VAV
The unit and the CAV unit are required to perform a so-called calibration in which whether or not a predetermined function is output is verified by a calibration measurement device. This calibration is usually performed once every six months. This verifies whether the pharmaceutical environment meets the management standards. Also in this case, for the same reason as described above, in many cases, a sufficient maintenance space is not secured, and there is a possibility that the execution of calibration may be hindered. Further, in the conventional air conditioning system, since the differential pressure control systems such as the VAV unit and the exhaust damper 25 are provided before and after the air supply direction across the work room, the mutual differential pressure control systems interfere with each other to cause hunting. However, there was a problem that the air volume became unstable. Further, in pharmaceutical factories and the like, energy saving control for reducing running costs is often performed by relaxing pharmaceutical environment standards during non-operation in recent years. Since a VAV unit and a differential pressure control system are provided for each case, complicated automatic control is required, resulting in an increase in cost. The present invention has been made in view of the above circumstances, and provides an air conditioning system capable of easily performing calibration, obtaining a stable air volume, and inexpensively constructing a system capable of switching to a non-operation mode. It is in.

[0006]

According to a first aspect of the present invention, there is provided an air conditioning system for supplying conditioned air from an air conditioner to a clean room, wherein the clean room has a predetermined temperature and humidity. An air-conditioning system that maintains an indoor air pressure and cleanliness, and has an air-blowing fan whose air volume can be varied by inverter control;
An air supply duct that connects the air conditioner and the clean room; a first HEPA filter that is provided downstream of the air blower fan of the air conditioner and through which air that is sent to the air supply duct passes; A second HEPA filter provided on the upstream side in the air supply direction near the outlet of the clean room to which the air supplied from the air supply duct passes, and an upstream side in the air supply direction near the second HEPA filter A volume damper provided on the downstream side and capable of variably adjusting the amount of conditioned air blown out from the outlet, and a conditioned air amount provided in the air supply duct and detecting the amount of conditioned air passing through the air supply duct, and the detection signal is An air supply-side air flow sensor used for a signal for controlling the air flow of the blower fan is provided.

In this air conditioning system, the first HEPA filter is provided downstream of the air blower of the air conditioner, so that the cleanness of the air sent from the air conditioner to the air supply duct is required in the clean room. It is equivalent to air cleanliness. Thus, the second HEPA filter provided near the outlet of the clean room does not clog due to dust collection. That is, the second HEPA filter does not need to be replaced semipermanently, and the DOP leak test and the replacement cost of a large number of HEPA filters in each factory room, which have conventionally been obstacles to maintenance costs, are no longer necessary. Therefore, for the second HEPA filter that does not cause clogging, CAV and VAV for increasing the air supply amount and securing the reference air volume become unnecessary. In other words, the air volume control of the main air supply duct and the VD
Initial setting of (Volume Damper) will ensure the reference air volume of the clean room. Accordingly, differential pressure control is not required. As a result, the maintenance for cleanliness control need only be performed for the first HEPA filter. Further, it is not necessary to provide a differential pressure control system before and after the clean room, and hunting does not occur. In addition, when switching to non-operational mode,
It is not necessary to perform control for each VAV provided in each of the plurality of clean rooms, and only the blower fan of the air conditioner is controlled to reduce the air volume (that is, save energy by reducing power).

According to a second aspect of the present invention, in the air conditioning system, a return duct that connects the clean room and a return side of the air conditioner is provided on the return duct and is collected on the return side of the air conditioner through the return duct. A return-side airflow sensor that detects a return airflow and uses the detection signal as a signal for monitoring the airflow of the blower fan.

In this air conditioning system, a return-side airflow sensor is provided in the return duct, so that the amount of air passing through the return duct can be directly detected. This enables more accurate monitoring of temperature, humidity, and room air pressure in combination with air volume detection by the air supply side air volume sensor.

According to a third aspect of the present invention, the air conditioning system has an operation switch for switching between an operation mode and a non-operation mode, and when the operation switch is set to the operation mode, the amount of air blown by the blower fan is a predetermined amount corresponding to the operation. When the operation switch is set to the non-operation mode, the control signal is sent to the blowing fan so that the blowing amount of the blowing fan is smaller than a predetermined amount corresponding to the operation time. Control means for transmitting a control signal.

In this air conditioning system, when the operation switch of the control means is operated, a control signal is output to the blower fan controlled by the inverter of the air conditioner so that the air flow corresponds to the operation mode or the non-operation mode. Is done.
That is, in the conventional air-conditioning system, control was required for each VAV unit and the like provided in a plurality of clean rooms. On the other hand, in this air-conditioning system, the operation mode was controlled by controlling only the blower fan of the air conditioner. Alternatively, switching to the non-operation mode becomes possible.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an air conditioning system according to the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a configuration diagram illustrating a concept of an air conditioning system according to the present invention.

In the air conditioner 31, a filter 33, a cooling unit 35, a heating unit 37, a humidifying spray 39, and a blower fan 41 are sequentially arranged in the blower direction. The return side 43 of the air conditioner 31 is connected to an OA duct and a return duct 47 communicating with each of the working rooms 45a, 45b, 45c.

A first HEPA filter 49 is provided in the air conditioner 31 downstream of the blower fan 41. An air supply duct 53 is connected to the supply side 51 of the air conditioner 31, and the air supply duct 53 is branched into a plurality of parts and connected to the respective working rooms 45a, 45b, 45c. That is, all air sent to the air supply duct 53 is supplied to the first HE
The light passes through a PA filter 49. As a result, the air sent to the air supply duct 53 is supplied to the
Air quality equivalent to the air quality (cleanliness) required in 5a, 45b, and 45c is obtained.

A second HEPA filter 57 is provided on the upstream side in the air supply direction near the air outlet 55 provided in each of the processing chambers 45a, 45b, 45c. Therefore,
The air supplied from the air supply duct 53 is supplied to the second HEPA.
After passing through the filter 57, the processing rooms 45a, 45b, 45c
It is to be blown out inside. This second HEP
Since the air after being collected by the first HEPA filter 49 passes through the A filter 57, the second HEPA filter 57 does not substantially collect the dust. That is, the second HEPA filter 57
Does not clog semipermanently.

In such a situation, the second H
The reason why the EPA filter 57 is provided is to collect dust mixed in the air supply due to the damage of the first HEPA filter 49, to collect dust mixed in the air supply due to the damage of the air supply duct 53, and the like. Is mentioned.

A volume damper 59 is provided near the second HEPA filter 57 on the upstream or downstream side in the air supply direction. The volume damper 59 is made up of the
The amount of conditioned air blown out from the outlet 55 opening to 5b, 45c can be variably adjusted. The volume damper 59 may be variably adjusted manually or automatically. Basically, the opening of the volume damper 59 is set only once at the start of the operation of the air conditioning system.

The air supply duct 53 is provided with an air supply side air volume sensor 61 for detecting an air volume passing through the air supply duct 53. The detection signal obtained by the air supply side air volume sensor 61 is used as a signal for controlling the air volume of the blower fan 41. That is, each of the working rooms 45a, 45
By summing the air volumes required by b and 45c, the air volume passing through the air supply duct 53 is obtained. The blower fan 41 of the air conditioner 31 is inverter-controlled so that the air volume obtained by the air supply-side air volume sensor 61 becomes the total air volume.

A branching return duct 47 is connected to each of the working rooms 45a, 45b, 45c. The branching return duct 47 is integrated into one return duct 47, and is connected to the return side 43 of the air conditioner 31 described above. Connected to.

Although not shown, the processing rooms 45a, 4
5b, 45c, other than the system of the return duct 47,
An exhaust duct that exhausts the air in the processing rooms 45a, 45b, and 45c to the outside may be connected. Workshops 45a, 45b,
45c may connect both the exhaust duct and the return duct 47, or only the return duct 47 or only the exhaust duct may be connected. For example, in a factory that handles powder, it is necessary to exhaust all the air in the factory room for explosion-proof reasons, so that only the exhaust duct is connected. Also in this case, the air supply amount to the work room is set only by adjusting the volume damper 59. Since the amount of exhaust from the exhaust duct is set to be constant, the indoor air pressure in the factory room in this case can be set as desired only by adjusting the volume damper 59.

The return duct 47 is provided with a return-side air volume sensor 63 for detecting a return air volume.
Thereby, the amount of air passing through the air supply duct 53 and the amount of air passing through the return duct 47 can be grasped, and the operation status of the blower fan 41 and the airflow path (the air supply duct 53, the work rooms 45a, 45b, and 45c) , The return duct 47) can be monitored with high accuracy.

Further, the processing rooms 45a, 45
By grasping the supply air amount and the return air amount for b and 45c, the process rooms 45a, 45b and 45c to which the conditioned air having a constant temperature and humidity is supplied can grasp the temperature and humidity with high accuracy. Become.

The air conditioner 31 is connected to control means 65 provided with an operation switch (not shown) for switching between an operation mode and a non-operation mode. As the control means 65, for example, a sequencer, a microcomputer, or the like can be used. The control means 65 transmits a control signal corresponding to a predetermined air volume to the blower fan 41 of the air conditioner 31 when the operation switch is operated. For example, when the operation switch is set to the operation mode, a control signal is sent to the blower fan 41 so that the blower amount of the blower fan 41 becomes a predetermined amount corresponding to the operation time. On the other hand, when the operation switch is set to the non-operation mode, a control signal is sent to the blowing fan 41 so that the blowing amount of the blowing fan 41 is smaller than a predetermined amount corresponding to the operation time. .

Next, the operation of the air-conditioning system 71 thus configured will be described. In this air conditioning system 71, the first HEPA filter 49 is provided inside the air blower 41 downstream of the air conditioner 31, so that the cleanliness of the air sent out from the air conditioner 31 to the air supply duct 53 is improved in the processing room 45 a. , 4
5b and 45c are equivalent to the required air cleanliness. Thereby, the second HEPA filter 57 provided near the outlet 55 of the processing room 45a, 45b, 45c.
Does not cause clogging due to dust collection. Therefore, the conventional CAV and VAV for securing the reference air volume by increasing the air supply amount to the clogged second HEPA filter 57 become unnecessary. That is, the air supply duct 5
If only the air volume control of No. 3 is performed, the process rooms 45a, 45b, 45
The reference airflow of c is secured. Accordingly, differential pressure control is not required.

As a result, maintenance for cleanliness management only needs to be performed for the first HEPA filter 49 alone. Further, there is no need to provide a differential pressure control system before and after the processing rooms 45a, 45b, 45c, and hunting does not occur. Further, at the time of switching to the non-operation mode, a plurality of processing rooms 45a, 45b,
There is no need to perform control for each VAV provided in each of the air conditioners 45c, and only the blower fan 41 of the air conditioner 31 is controlled to reduce the air volume (that is, save energy by reducing power).

Also, the working rooms 45a, 45b of a pharmaceutical factory, etc.
45c requires a DOP leak test to measure the efficiency of the filter. In this case as well, conventionally, a leak test was required for the filters provided in all the processing rooms 45a, 45b, and 45c. On the other hand, in the air conditioning system 71, only the first HEPA filter 49 was used. All you have to do is a leak test. In addition, the HEPA filter in each factory does not need to be replaced semipermanently.

Further, since the air volume is controlled by the air volume sensor 61 provided on the air supply duct 53, the periodic calibration only covers this portion.
The maintenance cost can be greatly reduced as compared with the related art in which all the working rooms 45a, 45b, 45c are targeted.

Since the return-side air volume sensor 63 is provided in the return duct 47, the amount of air passing through the return duct 47 can be directly detected. Accordingly, the temperature / humidity / room air pressure can be more accurately monitored in combination with the air volume detection by the air supply side air volume sensor 61.

Further, when the operation switch of the control means 65 is operated, a control signal is output to the blower fan 41 controlled by the inverter of the air conditioner 31 so that the air flow corresponds to the operation mode or the non-operation mode. Therefore, in the conventional air conditioning system, a plurality of processing rooms 45a, 45
In contrast to the necessity of controlling each of the VAV units and the like provided in b and 45c, this air conditioning system 71 controls only the blower fan 41 of the air conditioner 31.
Switching to the operation mode or the non-operation mode can be performed.

[0030]

As described above in detail, according to the air conditioning system according to the present invention, the first HEPA filter is installed downstream of the air blower fan of the air conditioner, so that the air is sent out from the air conditioner to the air supply duct. The cleanliness of the air to be used is equivalent to the cleanliness of the air required in the clean room. Thus, the second HEPA filter provided near the outlet of the clean room does not clog due to dust collection. Therefore, for the clogged second HEPA filter, CAV and VAV for increasing the air supply amount and securing the reference air volume become unnecessary, and if only the air volume control of the main air supply duct is performed, the clean room Is secured. As a result, maintenance for cleanliness management only needs to be performed for the first HEPA filter, and calibration can be easily performed. Further, since there is no need to provide a differential pressure control system before and after the clean room, hunting does not occur, and stable air volume control can be performed. In addition, when switching to non-operational mode,
There is no need to perform control for each VAV provided in each of the plurality of clean rooms, and only the blower fan of the air conditioner needs to be controlled, and a system capable of switching to the non-operation mode can be constructed at low cost.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a concept of an air conditioning system according to the present invention.

FIG. 2 is a configuration diagram illustrating a concept of a conventional air conditioning system.

[Explanation of symbols]

31 ... air conditioner, 41 ... blower fan, 43 ... return side,
45a, 45b, 45c… Construction room (clean room), 4
7 ... return duct, 49 ... first HEPA filter,
53 ... air supply duct, 55 ... outlet, 57 ... second HEP
A filter, 59 volume damper, 61 air supply side air flow sensor, 63 return air volume sensor, 65 control means, 71 air conditioning system

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hitoshi Noda 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. (72) Inventor Takaro Kawashima 1-2-Chome Moto-Akasaka, Minato-ku, Tokyo No. 7 F-term in Kashima Construction Co., Ltd. (reference) 3L061 BE02 BF07

Claims (3)

[Claims] 1. An air conditioning system that supplies conditioned air from an air conditioner to a clean room and maintains the clean room at a predetermined temperature, humidity, indoor air pressure, and cleanliness. An air conditioner equipped with a blower fan, an air supply duct connecting the air conditioner and the clean room, and an air supply duct installed downstream of the air blower fan of the air conditioner and through which air sent to the air supply duct passes. A second HEPA filter provided on the upstream side in the air supply direction near the air outlet of the clean room to which the air supply duct is connected, and through which air supplied from the air supply duct passes; A volume damper provided upstream or downstream of the air supply direction near the second HEPA filter and capable of variably adjusting the amount of conditioned air blown out from the air outlet; An air supply side air flow sensor provided in the air supply duct, detecting a conditioned air amount passing through the air supply duct, and using the detection signal as a signal for air flow control of the blower fan. Air conditioning system. 2. A return duct for connecting the clean room and a return side of the air conditioner, and a return air amount provided on the return duct and being collected on the return side of the air conditioner through the return duct and detecting a return air amount. The air conditioning system according to claim 1, further comprising a return-side airflow sensor whose detection signal is used as a signal for monitoring the airflow of the blower fan. 3. An operation switch for switching between an operation mode and a non-operation mode, wherein when the operation switch is set to the operation mode, the air flow of the air blow fan is set to a predetermined amount corresponding to the operation time. Control means for sending a control signal to the blower fan such that the blower fan has a blower amount smaller than a predetermined amount corresponding to the operating time when the operation switch is set to the non-operating mode. The air conditioning system according to claim 1 or 2, further comprising: