JPH0692835B2 - Room pressure control system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a room pressure control system for maintaining a constant pressure in a room.

(Prior art) In the biohazard room and radioisotope RI handling room, in order to prevent microorganisms and RI from leaking out,
The chamber pressure is controlled to be a constant negative pressure than the atmospheric pressure. Further, in a semiconductor production facility or an operating room of a hospital, the room pressure is controlled to be a constant positive pressure in order to prevent contaminated air from flowing into the room.

When controlling the room pressure, if the pressure difference between adjacent rooms or the difference between the room pressure and the atmospheric pressure is large, not only the opening and closing of the door of the room becomes heavy, but also contaminated air may flow into the room. Clean air may flow out of the room. Therefore, it is required to make the pressure difference as small as possible to ensure a stable constant differential pressure. In addition, it is desirable to be able to perform energy-saving operation while maintaining a stable constant differential pressure.

Therefore, in order to control the room pressure, the following negative pressure control method has been conventionally used.

As shown in FIG. 4, an air conditioner 04 is connected to the air intake 02 of the hazard chamber 01 via a wind conduit 03. A valve 05 is interposed in the wind conduit 03. on the other hand,
The air discharge port 06 of the hazard chamber 01 is connected to the sterilization filter 08 via the air duct 07. This wind conduit 07 has a valve
010 intervenes. Then, the inside of the hazard chamber 01 is maintained at a constant negative pressure by manually adjusting the two valves 05 and 010.

(Problems to be solved by the present invention) However, the filter in the air conditioner 04, the filter attached to the air intake port 02, and the air discharge port 06 on the exhaust side
It is not possible to maintain a constant room pressure because the amount of air sent into the hazard chamber 01 and the amount of air exhausted from the chamber 01 will change due to the clogging of the filter and sterilization filter 08 attached to the room. . Further, since the valves 05 and 010 are controlled to be opened and closed manually, it is difficult to reduce the air volume for energy saving operation at night.

Therefore, as shown in FIG.
Instead of 0, a system in which a motor damper 011 is provided in the air duct 07 on the exhaust side is considered. The motor damper 011 is controlled so that the pressure in the chamber 01 becomes constant by an output signal from a fine differential pressure gauge 012 that detects a pressure difference between the pressure in the hazard chamber 01 and the atmospheric pressure.

The motor damper 011 can deal with the clogging of the filter.

However, if the room pressure is controlled by simply controlling the motor damper 011 by the output signal from the slight differential pressure gauge 012, all the air volume discharged from the room 01 will be controlled. Becomes relatively large. Further, when switching to a small air volume for energy-saving operation at night, the valve 05 is manually opened and closed each time, which is troublesome and unrealistic.

The present invention has been made in view of such a problem, and an object thereof is to keep the room pressure constantly stable and to keep the room clean during non-working at night and use. The purpose of the present invention is to obtain a room pressure control system capable of smoothly switching to the minimum air volume operation without changing the room pressure in order to maintain the room pressure of a room that is not operated.

(Means for Solving the Problems) In order to solve the aforementioned problems, the present invention provides a blower that sends air through a blower side air duct into a room that is controlled to maintain a constant pressure. An exhauster is provided for exhausting air from this room via an exhaust side air duct, and an air volume adjusting device for opening and closing the air ducts on the air supply side and the exhaust side is provided. .

In that case, the air supply amount of the air supply amount adjusting device on the air supply side and the exhaust amount of the air amount adjusting device on the exhaust side are set to be equal so that the pressure fluctuation width in the room is suppressed within a predetermined range.

Furthermore, a constant air volume control device that is set to a minimum constant air volume and is controlled to flow a constant air volume in either one of the air supply side air duct and the exhaust side air duct is connected in parallel with the air volume adjusting device. In addition to either the air supply side air conduit and the exhaust air side air conduit, the amount of air supplied to the air supply side air quantity adjusting device and the exhaust air quantity of the air exhaust side air adjusting device are smaller than One air volume variable control device for adjusting the air volume is provided in parallel with the air volume adjusting device.

A fine differential pressure gauge that detects the pressure difference between the inside and the outside of the chamber controls the air volume variable control device based on the pressure difference.

According to the second aspect of the present invention, the plurality of chambers are provided, and the air flow rate adjusting device, the air flow rate constant control device, the air flow rate varying device, and the fine differential pressure gauge are provided for each of the chambers.

(Operation) With this configuration, in the present invention, during normal room pressure control, the air volume adjusting device is fully opened and air is blown into the room by the blower. Moreover, the same amount of air as the blown air is discharged from the chamber by the exhaust fan. And
The fine differential pressure gauge detects a pressure difference between the inside and the outside of the chamber, and the fine differential pressure gauge controls the air volume variable control device based on the pressure difference. In this way, the room pressure is maintained at a constant pressure.

Further, at night or when the room is not used, the air volume adjusting device is gradually closed to reduce the amount of air passing through the air duct, and finally the air volume adjusting device is completely closed. Therefore, a part of the air flows into and out of the room through the variable air volume control device and the constant air flow control device. In that case, the amount of air flowing through these control devices is smaller than the amount of air flowing into and out of the room during normal room pressure control. Then, since the air volume variable control device is controlled by the fine differential pressure gauge, a small air volume is controlled, so that the fluctuation of the room pressure becomes small.
As a result, the minimum air volume operation switching can be smoothly performed. Furthermore, the minimum air volume is ensured by the air volume constant control device. Therefore, the room pressure can be maintained constant with the minimum air volume, so that the output of the blower / exhaust fan can be small and the operation can be performed with less energy consumption.

(Example) Hereinafter, the example in the case of the hazard chamber of this invention is described using drawing.

FIG. 1 is a schematic explanatory view showing an embodiment of the room pressure control system according to the present invention.

As shown in FIG. 1, the hazard chamber 1 is provided with three air introduction ports 2,2,2 and three exhaust ports 3,3,3.

The three air inlets 2,2,2 are respectively provided with wind conduits 4a, 4a, 4a.
Are connected, and these wind conduits are connected to one wind conduit 4b. The air ducts 4a and 4b constitute the air blowing side air duct 4 of the present invention. The tip of the air duct 4b is connected to a blower 5 such as an air conditioner.

Of the three air ducts 4a, two air ducts 4a, 4a are provided with a first valve 6a and a second valve 6b, respectively. The first and second valves 6a and 6b constitute the air volume adjusting device 6 of the present invention. The other air duct 4a is provided with a variable air volume control device 7 including a valve. The variable air volume control device 7 adjusts the amount of air introduced into the hazard chamber 1 to maintain the pressure in the chamber 1 constant.

A fine differential pressure gauge 8 is provided in the hazard chamber 1,
The fine differential pressure gauge 8 is electrically connected to the air volume variable control device 7. The fine differential pressure gauge 8 detects the pressure difference between the inside and outside of the hazard chamber 1, and the air volume variable control device 7 is controlled based on the pressure difference.

On the other hand, the three exhaust ports 3,3,3 are also provided with the wind conduits 9a, 9a, 9 respectively.
a is connected. These wind ducts are one wind duct 9b
Are linked to. The air ducts 9a and 9b constitute the exhaust air duct 9 of the present invention. The tip of the air duct 9b is connected to the air blower 11 via the sterilization filter 10.

Of the three air ducts 9a, two air ducts 9a, 9a are provided with a third valve 12a and a fourth valve 12b, respectively. The third and fourth valves 12a, 12b constitute an air volume adjusting device 12. In the other wind conduit 9a,
A constant air volume control device 13 including a valve is provided.
The air volume constant control device 13 is designed to ensure a minimum air volume.

Next, the operation of this embodiment will be described.

In a normal operation pattern for performing room pressure control, the first to fourth valves 6a, 6b, 12a, 12b are opened. The blower 5 is driven to introduce air into the hazard chamber 1 through the first and second valves 6a and 6b and the air volume variable control device 7. At the same time, the air blower 11 is driven to move the air in the hazard chamber 1 to the third to fourth valves 12a,
The air is discharged to the outside through the air flow constant control device 13 and the sterilization filter 10. In that case, the amount of air introduced into the chamber 1 and the amount of air discharged from the chamber 1 are made substantially the same. Further, since the air flows through the valves 6a, 6b, 12a, 12b, the air volume flowing through the air volume variable control device 7 and the air volume constant control device 13 becomes small. As a result, the air volume variable control device 7 and the air volume constant control device 13 can be small in size.

The differential pressure between the pressure in the hazard chamber 1 and the atmospheric pressure is detected by the fine differential pressure gauge 8. The slight differential pressure gauge 8 controls the air volume variable control device 7 based on the detected differential pressure to keep the pressure in the hazard chamber 1 constant.

At night or when the room 1 is not used, the first and third valves 6a and 12a are gradually throttled so as to decrease by the same air amount at the same time. When both the 1st and 3rd valves 6a and 12a are completely closed, the 2nd and 4th valves
Similarly squeeze 6b and 12b, and close it completely at the end. The air volume to the air volume constant control device 13 is maintained at a constant pressure because the air volume variable control device 7 is controlled by the fine differential pressure gauge 8. Moreover, since the air volume flowing through the air volume variable control device 7 is small, the inside of the hazard chamber 1 Pressure fluctuations are very small. Therefore, the operation can be smoothly switched to the minimum air volume operation. As a result, the room pressure can be maintained at a substantially constant level with the minimum air volume, so that the outputs of the blower 5 and the air exhauster 11 can be small, and during operation at night and when the room 1 is not used, energy consumption is reduced. It consumes less.

For normal operation with room pressure control, the 1st to 4th valves
Reversely open 6a, 6b, 12a, 12b gradually.

The number of valves in the air volume adjusting devices 6 and 12 is appropriately increased or decreased according to the volume of the chamber 1. Further, in order to use the chamber 1 as a clean room for keeping a positive pressure, the position of the variable air volume control device 7 and the position of the constant air volume control device 13 may be interchanged. Furthermore, each valve 6a, 6b, 12a, 12
As a method of narrowing b, the first valve 6a and the third valve 12a and the second valve 6b and the fourth valve 12b may be respectively synchronized and controlled by a control signal from the central processing unit. .

FIG. 2 is a schematic explanatory view showing another embodiment of the present invention.

The same components as those in the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 2, in this embodiment, the hazard chamber 1 is further provided with another air inlet 2. A wind conduit 4a is also connected to this air inlet 2.
The wind conduit 4a is connected to the wind conduit 4b. This wind conduit
A fifth valve 6c is provided at 4a.

A draft chamber 14 is provided in the hazard chamber 1. The draft chamber 14 is connected to another exhaust fan 15 by a wind conduit 16. The wind conduit 16 has a sixth
The valve 12c and the sterilization filter 17 are interposed.

Next, the operation of this embodiment will be described.

The normal room pressure control and the energy-saving operation at night, etc. are the same as those in the above-mentioned embodiment, and therefore the description thereof is omitted.

When the draft chamber 14 is operated, the blower 5 and the exhaust fans 11 and 15 are driven to drive the fifth and sixth valves 6c and 12
Open c gradually so that c is increased by the same amount of air.
Air is introduced into the chamber 1 and the same amount of air is discharged from the chamber 1. During this period, the air volume variable control device 7 is controlled by the fine differential pressure gauge 8 and the air volume flowing through the air volume variable control device 7 is small, so that the room pressure does not vary much.

When stopping the draft chamber 14, each valve 6c, 1
On the contrary, 2c should be closed gradually.

The first valve 6a and the third valve 12a, the second valve 6b and the fourth valve 12b, and the fifth valve 6c and the sixth valve 12c can be interlocked with each other to change the air flow rate by the same amount.

FIG. 3 is a schematic explanatory view showing still another embodiment.

The same components as those of the above-described two embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, three hazard chambers 1 are provided.
Draft chamber is located in chamber 1 on the right side of the figure.
14 are provided. Each of the chambers 1 is provided with the respective valves 6a, 12a, 6c, 12c, the air volume variable control device 7, the air volume constant control device 13, and the fine differential pressure gauge 8 as in the above-described two embodiments. There is. However, in the case of this embodiment, the second and fourth valves 6b and 12b are unnecessary.

In this embodiment, the room pressure control is performed independently for each room 1. The control is exactly the same as that of the above-mentioned two embodiments, and the description thereof will be omitted.

(Effects of the Invention) As is apparent from the above description, the room pressure control system according to the present invention is provided with an air flow rate adjusting device for sending air into the room and an air flow rate adjusting device for discharging air to the outside of the room, and has a minimum constant air flow rate. A fixed air volume control device and a variable air volume control device that controls the air volume to perform room pressure control are installed, and this air volume variable control device is controlled by a fine differential pressure gauge that detects the pressure difference inside and outside the chamber. Therefore, the pressure in the room can be constantly maintained at a constant pressure.

In addition, since the air volume that flows through the air volume variable control device and the air volume constant control device is small, a small volume air volume variable control device and a constant air volume control device will suffice, so the air volume variable control device and the air volume constant control device can be downsized, A simple system can be constructed. Moreover, since the room pressure can be controlled only by controlling the air volume variable control device, the control is simplified and the air volume variable control device and the air volume constant control device can be formed in a small size. It is possible to form the variable air volume control device and the constant air flow control device that have high dynamic cost at low cost. As a result, the reliability is high, the failure can be easily found, and the room pressure control system can be formed at low cost.

Also, in order to perform the minimum air volume operation at night or when the room is not in use, the air volume adjustment device should be completely closed and some air should flow into and out of the room through the air volume variable control device and the air volume constant control device. Therefore, the small air volume flowing through the air volume variable control device is controlled. Therefore,
The fluctuation of the room pressure becomes small, and the switching of the minimum air volume operation becomes smooth. Moreover, since the minimum air volume operation is performed, the output of the blower / exhaust fan can be reduced, and energy saving operation can be performed.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of an embodiment of a room pressure control system for a hazard chamber according to the present invention, FIG. 2 is a schematic explanatory view of another embodiment of the present invention, and FIG. 3 is still another embodiment of the present invention. A schematic explanatory view of an example, FIG. 4 is a schematic explanatory view of a conventional room pressure control system,
FIG. 5 is a schematic explanatory view of another conventional room pressure control system. 1 ... Hazard room (room), 4 ... Air duct on air supply side, 5 ...
Blower, 6 ... Air volume adjusting device, 7 ... Air volume variable control device, 8 ... Fine differential pressure gauge, 9 ... Exhaust air duct, 11 ... Exhaust device,
12 …… Air volume adjustment device, 13 …… Air volume constant control device

Claims (2)

[Claims] 1. A chamber controlled to maintain a constant pressure inside, a blower for sending air into the chamber through an air blowing side air duct, and an air blower from the chamber through an exhaust side air duct. In a room pressure control system that includes an exhaust fan and an air flow rate adjusting device that opens and closes the air duct on the air supply side and the air duct on the exhaust side, respectively, the pressure fluctuation width in the room is predetermined. The air supply amount of the air amount adjusting device on the air sending side and the exhaust amount of the air amount adjusting device on the exhaust side are set to be equal to each other so as to be suppressed in the range of In one of the conduits, a constant air volume control device that is set to a minimum constant air volume and controls so that a constant air volume flows, is provided in parallel with the air volume adjustment device, and the air supply side air duct and the exhaust gas. Either the side air duct or the other side, An air volume variable control device that adjusts a minute air volume as compared with the air supply volume of the air volume adjustment device and the exhaust air volume of the air volume adjustment device on the exhaust side is provided in parallel with the air volume adjustment device, and further inside and outside the chamber. The room pressure control system is provided with a fine differential pressure gauge for detecting the pressure difference between the air flow rate control device and the air flow rate variable control device based on the pressure difference. 2. A plurality of the chambers are provided,
The room pressure control system according to claim 1, wherein the air flow rate adjusting device, the air flow rate constant control device, the air flow rate variable control device, and the fine differential pressure gauge are provided for each of these chambers.