JPS613934A - Controlling system of air conditioning of special working room - Google Patents

Abstract

PURPOSE:To save energy by a method wherein the rotating number of an air supplying fan is controlled by a computer so as to increase it when the opening degree of a damper is lower than an objective value but to decrease it when the opening degree of the same is lower than the objective value for a given period of time, in the control of air conditioning of a super LSI working chamber or the like. CONSTITUTION:A conputer 15 outputs opening and closing signals to dampers 5, 5' and converts the opening and closing signals into the opening degree of the dampers. The computer 15 decides whether the opening degree of the dampers 5, 5' have exceeded the objective upper limit value or not and increases the rotating number of the air supplying fan 7 immediately to restrain the increase of opening degrees of the dampers 5, 5' when the decision exceeds the objective upper limit value. When the opening degrees are lower than the objective upper limite value for a given periof of time, the rotating number of the air supplying fan 7 is reduced when it is decided, from the opening degree of the dampers 5, 5' and the flow amount of the air supplying fan 7, that the fan 7 is out of an unstable area. According to this constitution, energy saving may be promoted.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to air conditioning control of so-called clean rooms where special operations such as ultra-LSI manufacturing, precision machinery assembly, or biotechnology experiments involving unknown microorganisms are performed. Regarding the method.

[Prior art and its problems]

In order to prevent the intrusion of dust from the outside world and maintain an ultra-clean environment, it is necessary to control the indoor pressure to positive pressure, and to prevent the leakage of bacteria and harmful substances to the outside world, it is necessary to control the indoor pressure to negative pressure. There is a need.

In response to these demands, a control method has been proposed that saves power for air supply and exhaust air conditioning fans by maintaining a constant air volume and fixed pressure indoors, and by adopting two-way variable air volume operation. A conventional example of the system will be explained, thereby clarifying the object of the present invention.

Figure 4 is a block diagram showing a conventional example.
Each of the chambers 1' is equipped with a circulation duct 3.3' having a circulation fan 2.21 to maintain the desired pressure in the room.
The air outlet of each duct 3, 3' has an ultra-high performance filter (HE
A PA filter) 4.4' is installed.

An air supply duct 6 provided with a damper 5° and 5° is connected to the circulation fans 2 and 2', and an air supply fan 7 is provided on the inflow side of the air supply duct 6. Depending on the detection result of the installed differential pressure gauge 8,8", the controller 9
．． The dampers 5 and 5° are controlled to open and close via the dampers 9''.

In addition, a plurality of draft chambers 10, 10' are placed in the clan rooms 1, 1', and the draft chambers 10, 10'
．． An exhaust fan 1 is installed in the exhaust duct 11 connected to the exhaust fan 10'.
2 is provided.

In the figure, reference numeral 13 denotes a control microcomputer, and the computer 13 receives output from the draft chamber 10° and 10°, detects the number of units in use, and controls the rotational speed of the exhaust fan 12 based on the detection result. If any fluctuation occurs in the clean rooms 1 and 1', please use the differential pressure gauge 8.8.
' detects this and the dampers 5, 5 are activated by the controllers 9, 91.
゛Control opening and closing. By the way, if the desired pressure is not obtained even if the dampers 5, 5° are fully opened, the dampers 5, 5
' inputs a full open signal to the computer 13 via a limit switch (not shown) provided therein, and the computer 13 receives this full open signal and controls the air supply fan 7 to increase its rotational speed. .

By performing the two-step control of opening/closing the dampers 5 and 5' and controlling the rotation speed of the air supply fan 7 in this way, fine-grained control can be carried out, and the rotation speed of the air supply fan 7 can be controlled inadvertently. This makes it possible to realize power-saving operation without increasing the (Refer to the June 1983 issue of the magazine "Instrument" for the above-mentioned constant volume constant room pressure control system.) In this conventional control method, the limit is only on whether the dampers 5, 5" are fully opened or not. This is detected by a switch and increases the rotation speed of the air supply fan 7, and since the opening degree of the damper cannot be grasped at all times, there is a possibility of surging of the air supply fan 7 due to the damper being throttled too much. Since it is not possible to determine whether the opening degree is close to fully open, there is a risk that a quick response may be lacking.

[Purpose of the invention]

The purpose of the present invention is to eliminate the disadvantages of the conventional example, and to provide a special working room in which fine-grained control is performed to bring the average opening of the damper closer to the target value, and as a result, further energy saving is achieved. The objective is to provide an air conditioning control system for

[Key points of the invention]

However, according to the present invention, the purpose of the lever is to detect the number of draft chambers in use and have the computer control the rotation speed of the exhaust fan, and to detect room pressure fluctuations to open and close the damper and control the rotation speed of the supply air fan. In a constant volume constant room pressure control system that performs two-stage air supply control, the damper can be opened and closed by a computer, and if the damper opening exceeds the i standard upper limit, the computer will control the rotation speed of the air supply fan. If the damper opening does not exceed the target value for a certain period of time, the computer will gradually lower the rotational speed of the air supply fan.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the invention, FIG. 2 is an operation waveform diagram of the same as above, and FIG. 3 is a flowchart. In FIG. 1, the same components as those in FIG. is attached.

That is, the draft chambers 10.10' in the chrysorooms 1 and 1' send drive signals to the microcomputer 13, and the computer 13 receives this signal, detects the number of draft chambers 10.10'' in use, and exhausts the air accordingly. The rotation speed of the fan 12 is controlled.In the present invention, the pressure detection signal from the differential pressure gauge 8.81 disposed in the room 1, 1' is introduced into the computer 13, and the inflow to the circulation fan 2, 2'' is Damper 5, installed on the side to computer 1
The computer 13 controls the opening and closing of the dampers 5 and 5'. This eliminates the need for the conventional controller 9°9° (see Figure 4), and the open/closed state of the damper 5.5° is controlled by an open/close control signal (digital value) generated by the computer 13 itself.
Since it can be detected by converting it directly into the damper opening degree, limit switches and wiring provided on the damper 5.5' can also be omitted.

On the other hand, the point that a rotation control signal is given to the air supply fan 7 and the rotation speed is controlled by the computer 13 is the same as in the conventional case, and the computer 13 simultaneously detects the air volume of the air supply fan 7 by issuing this rotation control signal. It will be possible.

In this way, the dampers 5 and 5' are opened and closed, and the air supply fan 7
As shown in Figure 3, the stesobu is used to determine whether the opening degree of the dampers 5 and 5 degrees has exceeded the target upper limit set slightly before fully opening. ), the rotation speed of the air supply fan 7 is immediately increased. As a result, the dampers 5, 5'' will not open any further.

In FIG. 2, A indicates the opening degree of the dampers 5, 5' controlled by the method of the present invention, B indicates the rotation speed of the air supply fan 7, and the damper 5° 5' without rotation speed control. By comparing C, which assumes the movement of , with A, the difference from the conventional example can be seen.

By the way, the dampers 5, 5' exceed the target upper limit value (if not, the computer 13 determines that the dampers 5, 5' exceed the target upper limit value based on the opening degree of the dampers 5, 5' and the air volume of the air supply fan 7).
It is determined whether or not the lens is within the surging range due to excessive tightening of '' and is in an unstable region (Step C).

If it is outside the surging range, the computer 13 determines whether the opening degree of the dampers 5, 5' has exceeded the target upper limit value for a certain period of time (Step 2). If not, the computer 13 gradually lowers the rotation speed of the air supply fan 7 (Step E). Thereby, the air supply fan 7 can be operated in a further power-saving manner. In this case, damper 5
°5' gradually opens and approaches the target upper limit value.

On the other hand, if the air supply fan 7 is within the surging range at step C, the computer 13 controls the rotation speed of the air supply fan 7 to be reduced (step C).

〔Effect of the invention〕

As described above, in the air conditioning control system for a special work room of the present invention, the computer detects the number of draft chambers in use and controls the rotation speed of the exhaust fan, and detects room pressure fluctuations to open and close the damper and air supply. In a constant air volume constant room pressure control system that performs two-stage air supply control, namely fan rotation speed control, the damper is directly controlled by a microcomputer without using an adjustment needle, so the target upper limit value of the damper opening can be adjusted. This can be easily changed just by changing the memory, making it easy to change the setting of the tolerance value for disturbance. In addition, on Saturdays, holidays, or when there are few disturbances, the rotation speed of the air supply fan naturally decreases, making it possible to achieve even greater energy savings.Additionally, advanced control is also possible to maintain the average damper opening at the target value as much as possible. It is ugly.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the air conditioning control method for a special work room of the present invention, Fig. 2 is a waveform diagram showing the operation of the damper and air supply fan in Fig. 1, and Fig. 3 shows the embodiment. Flowchart, FIG. 4 is a block diagram showing a conventional method. 1.1'...Clean room 2,21...Circulation fan 3.3'...Circulation duct 4.4'...Ultra high performance filter 5.5'...Damper 6...Supply air duct 7・
・・Air supply fan 8, 8" ・・Differential pressure gauge 9
．． 9°...controller

Claims (1)

[Claims] The computer detects the number of draft chambers in use and controls the rotation speed of the exhaust fan, and detects room pressure fluctuations to perform two-step air supply control: opening and closing the damper and controlling the rotation speed of the air supply fan. In the room pressure control system, the damper can be opened and closed by a computer, and if the damper opening exceeds the target upper limit, the computer immediately increases the rotational speed of the air supply fan and maintains the damper opening at the target for a certain period of time. An air conditioning control system for special work rooms that uses a computer to gradually reduce the rotation speed of the air supply fan if the specified value is not exceeded.