JP2002228242A - Method and apparatus for room pressure control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for room pressure control based upon an air amount difference between a supply air amount and an exhaust air amount by grasping a relation between the air amount difference and room pressure in a microbiological laboratory, a radioactive waste treating equipment, or a clean room, etc., which have a structure where air tightness between the inside and outside of a room is relatively secured. SOLUTION: A variable supply air amount apparatus 3 for making variable a supply air amount and a variable exhaust air amount apparatus 11 for making an exhaust air amount variable are connected with a room 61. The variable supply air amount apparatus 3 and the variable exhaust air amount apparatus 11 are connected to a control device 21, to which device an indoor temperature detector 17 and a supply air temperature control device 7 are connected. Provided that a room pressure control device 1A is constructed as such, the interior of the room 61 is set to arbitrary pressure owing to a difference between the supply air amount and the exhaust air amount, and the air amount is varied in response to a thermal load in the room, whereby it is possible to keep the temperature in the room unchanged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for controlling a room pressure, and more particularly to a method and an apparatus for controlling each room in a relatively airtight manner such as a microbiology laboratory, a radioactive waste treatment facility, or a clean room. To maintain the chamber pressure at positive or negative pressure,
The present invention relates to a method and an apparatus for controlling a room pressure for maintaining a room temperature at a predetermined temperature.

[0002]

2. Description of the Related Art Conventionally, when controlling a room pressure to a negative pressure,
Adjustment of the supply air volume or the exhaust air volume to the closed room was performed by the room slight differential pressure control air conditioner 60 shown in FIG. FIG.
FIG. 1 is an overall configuration diagram of a conventional indoor slight differential pressure control air conditioner. As shown in the figure, for example, the sealed chamber 61 is controlled to a buffer adjustment chamber 63 adjusted to a negative pressure of −20 Pa with respect to the atmospheric pressure, and also controlled to a negative pressure of −40 Pa with respect to the atmospheric pressure. And a laboratory 65. Closed room 6
1 is isolated from the atmosphere or the hallway by a wall 67 and is maintained at the above-mentioned room pressure. A first chamber pressure controller 69 is provided between the buffer adjustment chamber 63 and the laboratory 65, and a second chamber pressure controller 71 is provided between the buffer adjustment chamber 63 and the corridor. The chamber 61 controlled by the chamber pressure control device is composed of a plurality of chambers 61a, 61b, 61c,..., And the respective chambers 61a, 61b, 61
The main air supply duct 75 is provided from the air supply fan 73 to c,.
And a variable air volume device 79 for varying the amount of air supplied to a branch air supply duct 77 branched from the main air supply duct 75.
And fresh air is supplied. In the variable air volume device 79, the supply air volume is variably controlled by the air volume adjusting device 81, and the respective chambers 61a, 61b, 61
The supply air volume to be supplied is controlled according to the room pressures of c,. A small differential pressure oscillator 83 is connected to the air volume adjusting device 81, and detects a differential pressure between the chamber pressure of each of the chambers 61a, 61b, 61c,... And the atmospheric pressure, and detects each of the chambers 61a, 61.
The air pressure adjusting device 81 adjusts the fine differential pressure by changing the air supply amount of the variable air volume device 79 so that the chamber pressures of b, 61c,. In addition, each room 61
, 61b, 61c,...
Is exhausted by an exhaust fan 87 via a main exhaust duct 85, and a constant air volume is exhausted by a constant air volume device 89 provided in the branch exhaust duct 83. As described above, in the conventional indoor slight differential pressure control air conditioning equipment, the room pressure of each chamber 61 is controlled by adjusting the supply air flow while keeping the exhaust air flow constant.

[0003]

However, in the conventional indoor slight differential pressure control air conditioning equipment, since the air volume adjusting device operates only to control the room pressure, there are facilities in which the indoor thermal load fluctuates greatly, and air conditioning equipment. In a facility with multiple laboratories that use a single air supply / exhaust system, if the heat load varies greatly from one laboratory to another, it is not possible to simultaneously remove the indoor heat load and control the room pressure by airflow control alone. It was difficult. Although FIG. 6 shows a case where the exhaust air volume is a constant air volume device, a method of controlling this device with a variable air volume and controlling, for example, based on the indoor temperature is conceivable. However, in this method, each of the air supply and exhaust air variable devices operates independently, and since the indoor temperature is controlled independently, there is a problem that both the room pressure and the room temperature cannot be stably controlled. .

Further, in the conventional air conditioning equipment for controlling the slight differential pressure in the room, the resistance of filters (not shown) provided on the air supply side and the air exhaust side, and the dynamic characteristic hysteresis caused by the constant air volume device on the air exhaust side and the time difference between the operation and the operation, It is also conceivable that the constant air volume from the constant air volume device is not exhausted constantly and the room pressure fluctuates.

The present invention is directed to a method and an apparatus for controlling a room pressure, focusing on the above problems, and in particular, relates to a microbiology laboratory, a radioactive waste treatment facility, or a clean room having a structure in which airtightness between the inside and outside is relatively maintained. SUMMARY OF THE INVENTION It is an object of the present invention to provide a room pressure control method and apparatus for grasping a relationship between a difference in air volume between a supply air volume and an exhaust air volume and a room pressure and controlling a room pressure based on the air volume difference.

Another object of the present invention is to maintain the room temperature at a predetermined temperature by controlling the air flow difference between the exhaust air and the supply air to keep the room pressure constant, and changing the air flow difference according to the room temperature. It is another object of the present invention to provide a method and an apparatus for controlling a room pressure in which both the room pressure and the room temperature are controlled to appropriate values.

[0007]

A room pressure control method according to the present invention sets an arbitrary pressure in a room according to a difference between a supply air volume and an exhaust air volume, and varies an air volume according to a heat load in the room. The temperature in the room was kept constant. Further, the room pressure control device according to the present invention connects the air supply variable air volume means for varying the supply air volume and the exhaust variable air volume means for varying the exhaust air volume to the chamber, A control unit is connected to the air volume unit and the exhaust variable air volume unit, and the control unit makes the air volume difference between the supply air volume to the chamber and the exhaust air volume constant, and sets the chamber to an arbitrary pressure.

[0008] A room temperature detecting means is connected to the control means so as to vary the air supply and exhaust air flows in response to the detection of the room temperature by the room temperature detecting means. An air temperature control means may be provided and the air supply temperature control means may be connected to the control means so that the air supply temperature can be adjusted according to the room temperature.

[0009]

According to the above arrangement, it is first checked whether or not the difference between the supply air volume and the exhaust air volume is an appropriate value. If the difference between the supply air volume and the exhaust air volume is an appropriate value, the room temperature is checked. If the difference between the supply air amount and the exhaust air amount is not an appropriate value, the exhaust air amount is adjusted to control the air amount difference between the supply air amount and the exhaust air amount. The exhaust air volume has a characteristic that an appropriate air volume difference is determined when the target chamber pressure is determined. From the appropriate airflow difference, the airflow difference between the supply airflow and the exhaust airflow of the system is determined. Next, it is checked whether the room temperature is appropriate. If the room temperature is an appropriate value, the airflow difference between the supply airflow and the exhaust airflow is checked again. If the room temperature is not appropriate,
The air supply amount is controlled by an air supply amount adjusting device as a control means so that the air supply amount becomes an appropriate air supply amount according to the heat load. When the supply air volume becomes the minimum supply air volume during this control, the supply air volume is fixed to the minimum supply air volume, and the exhaust air volume is the difference between the supply air volume and the exhaust air volume determined by the room pressure adjusting device as the control means. It is controlled so as to have a difference in air volume. Then, the supply air temperature is controlled to an appropriate value by the supply air temperature adjustment device attached to the supply side so that the indoor heat load can be removed. by this,
The room pressure maintained at the positive pressure or the negative pressure, and the predetermined room temperature according to the heat load, the control means keeps the air flow difference between the supply air flow and the exhaust air flow constant, and heats the air supply as necessary. Alternatively, appropriate values can be obtained for both by cooling.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment of a method and apparatus for controlling a room pressure according to the present invention will be described in detail with reference to the accompanying drawings. The same parts as those in the conventional example are denoted by the same reference numerals, and description thereof will be omitted. FIG. 1 is an overall configuration diagram of a room pressure control device 1 according to a first embodiment of the present invention, FIG. 2 is a diagram illustrating characteristics of the room pressure control device, and FIG. 3 is a diagram illustrating a relationship between supply air volume and exhaust air volume. FIG. 4 is a flowchart of the room pressure control device 1.

In FIG. 1, for example, the sealed chamber 61 of the chamber pressure control device 1 is controlled to a buffer adjustment chamber 63 adjusted to a negative pressure of -20 Pa and a negative pressure of -40 Pa, as in the conventional example. And a closed chamber 61.
Are isolated from the atmospheric pressure or the corridor by walls 67 and are maintained at the room pressure, respectively. The chamber 61 in which the chamber pressure Pc is controlled is composed of a plurality of chambers 61a, 61b, 61c,..., And the respective chambers 61a, 61b, 61
The main air supply duct 75 is provided from the air supply fan 73 to c,.
Are provided in each of the branch air supply ducts 77 branched from the main air supply duct 75, and supply air flow variable devices 3a, 3b, 3c... ing. From the air supply fan 73 to the air supply system of the main air supply duct 75, an air supply temperature control device 7 for heating or cooling the temperature of the air supply to a predetermined temperature and controlling the temperature, An air supply temperature detector 9 that measures the temperature Ta of the air supply air is provided in series.

Further, each of the chambers 61a, 61b, 61
The air of c,... is sucked by the exhaust fan 87 from each branch exhaust duct 83 via the main exhaust duct 85, and the exhaust variable air flow devices 11a, 11b, 11c ...
, A variable air volume is exhausted. The air supply air supply device 3 and the exhaust air supply device 11 are connected to an air flow adjusting device 15, and the air flow adjusting devices 15a, 15b, 15c.
The respective rooms 61a, 61b, 61
A variable air volume is supplied from the air supply variable air volume device 3 and a variable air volume is exhausted from the exhaust variable air volume device 11 in accordance with the room pressure Px of c,. That is, the air volume adjusting device 15
As shown in FIG. 2, the air volume difference Qc between the supply air volume Qi and the exhaust air volume Qo is, as shown in FIG.
c,... are supplied and discharged in accordance with the target chamber pressure Px (hereinafter, referred to as the chamber pressure Px). FIG. 2 shows the air flow difference Qc between the supply air flow Qi and the exhaust air flow Qo on the horizontal axis, and the room pressure Px on the vertical axis, and uses the appropriate air flow difference curve QL in FIG.
Indicates the correlation obtained. As a result, a filter (not shown) provided on the air supply side or the exhaust side is clogged and the resistance changes, and even if the air volume flowing through both or any of the air supply variable air volume device 3 and the exhaust variable air volume device 11 changes. Since the air supply variable air volume device 3 and the exhaust variable air volume device 11 are controlled based on the air volume difference Qc,
A constant chamber pressure Px can be obtained. As described above, the air supply variable air volume device as the air supply variable air volume device 3 and the exhaust air variable air volume device as the exhaust gas variable air volume device 11 are connected to the control device of the air volume adjusting device 15 composed of a computer or the like. By doing so, control is performed to keep the air flow difference Qc between the supply air flow Qi and the exhaust air flow Qo constant.

Each of the chambers 61a, 61b, 61
An indoor temperature detector 17 for measuring the indoor temperature (hereinafter, referred to as room temperature Tc) is provided in c,..., and transmits a detected temperature signal to the room temperature adjusting device 19. Room temperature controller 1
Reference numeral 9 denotes an air supply temperature control device 7 and an air supply temperature detector 9 provided in series with the main air supply duct 75, and an air supply variable air volume device 3a, 3
b, 3c... The room temperature controller 19
Upon receiving a temperature signal from the indoor temperature detector 17, a command is output to the supply air temperature control device 7, and the supply air is heated or cooled so that the room temperature Tc becomes a predetermined temperature. The supply air temperature detector 9 receives a command output from the room temperature controller 19 to the supply air temperature control device 7 and determines whether the supply air supplied to the room by the supply air temperature control device 7 has reached the set temperature. , Or not, and feeds back to the supply air temperature control device 7. Thereby, the room temperature controller 1
From 9, air at an accurate temperature is supplied in response to a heating or cooling command to the supply air temperature control device 7.

Each of the chambers 61a, 61b, 61
When the heat loads Ha of c,...
Each of the room temperature adjusting devices 19a, 19b, 19c... Outputs a command to each of the supply air-blowing devices 3a, 3b, 3c. The amount of variable wind to be noticed is increasing or decreasing. In accordance with the increase and decrease in the amount of variable air supplied to each room, the air volume adjusting device 15 outputs a command to increase and decrease the amount of exhaust air to be exhausted to the exhaust variable air amount device 11, so that the supply air volume Qi and the exhaust air volume Qo are compared. The air volume difference Qc is controlled so as to become the set room pressure Px in each room.

FIG. 3 shows the heat load Ha on the horizontal axis and the air flow Qa on the vertical axis, and shows the supply air flow curve RL by the solid line in the figure, and the supply air flow Qi supplied indoors with respect to the heat load Ha. Shows the correlation. Also, the exhaust air volume curve YL is indicated by a dotted line in the figure, and by setting the appropriate exhaust air volume Qo with respect to the appropriate supply air volume Qi, an appropriate air volume difference Qc can be adjusted in accordance with the set room pressure Px in each room. It shows that it can be obtained. As described above, the air supply amount is controlled by the air amount adjustment device 15 so that the supply air amount becomes an appropriate supply air amount according to the heat load. During this control, the supply air volume Qi is fixed to the minimum supply air volume Qmin as shown by the dashed line, and the exhaust air volume Qo is the air volume difference Qc between the supply air volume Qi and the exhaust air volume Qo determined by the air volume adjustment device 15. Is controlled. At this time, when the heat load is large and the temperature does not reach the predetermined temperature even if the minimum supply air volume Qmin is supplied to the room 61, the air supply is heated by the air supply temperature control device 7 so that the room becomes the predetermined temperature. Alternatively, it is supplied after cooling. Thereby, the heat load in the room can be removed and the room temperature can be controlled to the desired room temperature Tc.

The operation of the room pressure control device 1 configured as described above will be described with reference to the flowchart of FIG. In the figure, for example, air leakage from each chamber 61 is eliminated or each room temperature adjusting device 19a, 1
After the cleaning of 9b, 19c, etc. is performed, the supply air volume Qi and the exhaust air volume Qo such that the room pressure Px becomes the target pressure.
Periodic inspection, such as adjusting the air flow difference Qc, is performed (step 1). After this periodic inspection, the supply air volume Qi and the exhaust air volume Q
It is determined whether or not the airflow difference Qc of o is an appropriate value (step 2). If it is determined in step 2 that the air volume difference Qc is not within the appropriate value (NO), the process proceeds to step 3. In step 3, the air volume adjusting device 15 sends the exhaust variable air volume devices 11
Command to adjust the exhaust air volume Qo and supply air volume Qi
Is controlled so that the difference Qc in the air flow between the air flow and the air flow enters an appropriate value. At this time, according to the relationship between the room pressure Px and the airflow difference Qc shown in FIG.
This is performed by controlling o. After adjusting the exhaust air variable device 11 in step 3, the process returns to step 2.

If it is determined in step 2 that the air volume difference Qc is at an appropriate value (YES), the process proceeds to step 4. In step 4, it is determined whether or not the room temperature Tc is an appropriate value.
If the room temperature Tc is within the appropriate value in step 4 (YE
In S), the process goes to Step 5 and the control of the room pressure Px and the room temperature Tc of each chamber 61 is continued from Step 2. If the room temperature Tc does not fall within the proper value in step 4 (NO), the procedure goes to step 6. In step 6, the air volume adjusting device 15
Outputs a command to each air supply variable air volume device 3 to supply air volume Q
i is adjusted so that the room temperature Tc is controlled to enter an appropriate value.
In step 6, the air supply variable air volume device 3 is adjusted, and after the room temperature Tc has entered an appropriate value, the process proceeds to step 7. At this time,
In accordance with the relationship between the heat load Ha and the air flow Wa shown in FIG. 3, a command is output to the air supply variable air flow device 3 to control the supply air flow Qi. In step 7, it is determined whether or not the supply air volume Qi is greater than a minimum air volume Qmin determined from the number of ventilations. Ventilation rate is ON-O in pulse form
The FF is repeatedly performed, and the ON-OFF time may be appropriately selected. Minimum air volume Q in step 7
If it is larger than min (YES), the procedure goes to step 5, and the control of the room pressure Px and the room temperature Tc of each chamber 61 is continued.

If it is determined in step 7 that the air volume is smaller than the minimum air volume Qmin (NO), the flow proceeds to step 8. In step 8, the supply air volume Qi is fixed to the minimum air volume Qmin. In step 9, the air flow difference Q between the supply air flow Qi and the exhaust air flow Qo
c is maintained at an appropriate air volume difference Qca. In step 10, a heating or cooling command is output from the room temperature adjusting device 19 to the supply air temperature control device 7 so that the indoor heat load Ha becomes a blowout temperature at which the heat load Ha can be removed.
To control the room temperature Tc to a predetermined temperature. When Step 10 is completed, the process goes to Step 5, and the control of the room pressure Px and the room temperature Tc of each chamber 61 is continued.

FIG. 5 is an overall configuration diagram of a room pressure control device according to a second embodiment of the present invention. Here, the first shown in FIG.
In the room pressure control device 1 according to the embodiment, the room pressure Px and the room temperature Tc are controlled using the air volume adjustment device 15 and the room temperature adjustment device 19. That is, the air volume adjusting device 15 is connected to the supply air volume device 3 and the exhaust air volume device 11,
The air volume difference Qc between the supply air volume Qi and the exhaust air volume Qo is controlled so as to become the set room pressure Px in each room. Also,
The room temperature adjusting device 19 is connected to the air supply variable air flow device 3 via the air supply temperature control device 7 and the air flow amount adjusting device 15, and controls the increase and decrease of the supply air volume Qi or the temperature of the supply air. Control is performed so that the room temperature Tc is set.

On the other hand, the room pressure control device 1A according to the second embodiment shown in FIG. 5 is a system in which the functions of the air volume control device 15 and the room temperature control device 19 are combined into one control device 21. The control device 21 is connected to the air supply variable air volume device 3, the exhaust gas variable air volume device 11, the air supply temperature control device 7, the air supply temperature detector 9, and the indoor temperature detector 17, respectively.

First, the respective control devices 21a, 21
., b, 21c... correspond to the relationship between the room pressure Px and the air flow difference Qc in FIG.
c ... and the exhaust variable air amount devices 11a, 11b, 11c ...
To control the supply air volume Qi and the exhaust air volume Qo, so that the chamber pressure P of each of the chambers 61a, 61b, 61c,.
The air volume difference Qc is set to be x. Further, the control device 21 outputs a command to the air supply variable air flow device 3 to control the air supply air volume Qi based on the relationship between the heat load Ha and the air volume Qa indicated by the solid line RL in FIG. , 61b, 6
The supply air volume Qi is set so as to be the room temperature Tc of 1c,. Further, the control device 21 outputs a command to the supply air temperature control device 7 to control the temperature of the supply air, so that the supply air is controlled to reach the room temperature Tc of each of the chambers 61a, 61b, 61c,. Temperature is set. Thus, the same control as that of the room pressure control device 1 of the first embodiment can be performed by the control means as one control device 21.

In the above embodiment, the example in which the air supply temperature control device 7 is disposed downstream of the air supply fan 73 has been described.
It may be arranged on the upstream side. In addition, although the example in which the room pressure is a negative pressure is shown, in the case of a positive pressure in a case where air in a room such as a clean room may leak to the outside, a system in which the functions of supply air volume control and exhaust air volume control are reversed is adopted. Thereby, the positive pressure control and the room temperature control can be performed simultaneously.

As described above, the present invention has an air supply variable air volume means for varying the amount of air supplied to the room, and an exhaust variable air volume means for varying the amount of air discharged from the room. Since the airflow difference between the supply air flow rate to the chamber and the exhaust air flow rate is kept constant and the control means for controlling the room to a constant positive or negative pressure is used, the exhaust and air supply airflow rate is reduced. In conjunction with controlling the air volume difference to keep the room pressure constant, changing the air volume difference according to the room temperature, maintaining the room temperature at a predetermined temperature, and controlling both the room pressure and the room temperature to appropriate values by both I am trying to do it.

[0024]

As described above, according to the room pressure control method and apparatus of the present invention, the interior of the room is set to an arbitrary pressure by the difference between the supply air volume and the exhaust air volume, and the room pressure is controlled according to the heat load in the room. By changing the air flow, to maintain the temperature of the room constant, or to connect the air supply variable air volume means for varying the supply air volume and the exhaust variable air volume means for varying the exhaust air volume to the room, A control means is connected to the air supply air supply means and the exhaust air flow supply means, and the control means makes the air flow difference between the air supply air flow and the exhaust air flow to the room constant, and sets the interior to an arbitrary pressure. This makes it possible to keep the pressure in the chamber constant and to keep the room temperature in the chamber constant.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a room pressure control device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing characteristics of a room pressure control device according to the present invention.

FIG. 3 is a diagram illustrating a relationship between a supply air volume and an exhaust air volume according to the present invention.

FIG. 4 is a flowchart of a room pressure control device according to the present invention.

FIG. 5 is an overall configuration diagram of a room pressure control device according to a second embodiment of the present invention.

FIG. 6 is an overall configuration diagram of a conventional indoor slight differential pressure control air conditioner.

[Explanation of symbols]

1A ... room pressure control device, 3 ... air supply variable air volume device, 7 ...
... Air supply temperature control device, 9 ... Air supply temperature detector, 11 ...
... Exhaust variable air volume device, 15 ... Air volume adjustment device, 17 ...
Indoor temperature detector, 19: room temperature controller, 21: controller, 61: chamber, 63: buffer chamber, 65: laboratory, 67: wall, 73: air supply fan, 75 ... ... Main air supply duct, 77 ... Branch air supply duct, 83 ... Branch exhaust air duct, 85 ... Main exhaust air duct, 87 ... Exhaust fan, Qi ... Air supply air volume, Qo ... Air exhaust air volume, Qc ...
Air volume difference

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 3L056 BD02 BD04 BF04 3L058 BF00 BG04 3L061 BF01

Claims (4)

[Claims] 1. A room, wherein a room is set to an arbitrary pressure by a difference between a supply air amount and an exhaust air amount, and the air amount is varied in accordance with a heat load in the room to keep the temperature in the room constant. Pressure control method. 2. An air supply variable air volume means for varying the supply air volume and an exhaust variable air volume means for varying the exhaust air volume are connected to the chamber. Control means is connected to the variable air volume means, and the control means makes the air volume difference between the supply air volume and the exhaust air volume to the chamber constant,
A room pressure control device, wherein the room is set at an arbitrary pressure. 3. A room temperature detecting means is connected to said control means,
3. The air volume of the supply air volume and the exhaust air volume is varied according to the detection of the room temperature by the room temperature detection means.
3. The room pressure control device according to 1. 4. An air supply temperature control means is provided on the air supply side of the chamber, and the air supply temperature control means is connected to the control means, so that the air supply temperature can be adjusted according to the room temperature. The room pressure control device according to claim 3.