JPH0114497B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exhaust gas control device in an air conditioning zone that saves energy.

Facilities with multiple exhaust systems and continuous rooms, such as IC manufacturing factories, research laboratories, and hotel kitchens, require large amounts of highly clean constant temperature and humidity air due to process or environmental reasons. However, since the air discharged from each exhaust system cannot be recycled, outside air must be treated and brought in. In this case, the outside air load (the energy required to process the outside air) can reach as much as 35% of the total air conditioning load (the energy required to process the air).

The main purpose of the present invention is to reduce the outside air load in such facilities.

For this purpose, it is also possible to install an exhaust fan in each of a number of exhaust devices and control the amount of exhaust air individually.
However, in this case, there are problems in terms of maintenance and management, and it is not practical. Therefore, it is most common to collect a large number of exhaust devices (draft chambers) into a system using ducts, and connect each system with a large exhaust fan. Even when the main unit is in operation, the large exhaust fan is in full operation, unnecessarily exhausting indoor air. In addition, even when a damper is attached to each exhaust system to control opening and closing, fluctuations in usage rate can cause fluctuations in exhaust performance, disrupting the air volume balance, causing harmful gases to diffuse into the surrounding area from the production process, and odors coming from the kitchen. This may lead to situations such as leakage of information.

Another object of the invention is to provide an exhaust system that avoids such problems.

As shown in the embodiment of the drawings, the main configuration of the exhaust gas control device according to the present invention is that a large number of draft chambers 2 are provided in an air conditioning zone 1, and exhaust gas is provided so that each draft chamber 2 communicates with the outside air. An air duct 3, an exhaust fan 4 interposed in the exhaust air duct 3, a variable speed motor 5 for driving the exhaust fan 4, and a usage status sensor for detecting the usage status of each draft chamber 2. 6, a calculator configured to integrate the required exhaust air volume based on the signal from the usage status sensor 6, and a controller 7 configured to control the rotational speed or frequency of the variable speed motor 5 based on the output signal from this computer. ,
It is made up of In order to balance the indoor pressure in the air-conditioning zone 1, in addition to the above-mentioned device, the static pressure difference between the air-conditioning zone 1 and the surrounding building space, such as a corridor or other perimeter zone 8, is detected. differential pressure gauge 9 and air conditioning zone 1
A rethane air passage 12 that communicates with the suction side air passage 11 of the air conditioner 10, and a rethane damper 13 that is attached to the rethane air passage 12 and whose opening degree is adjusted according to the signal from the differential pressure gauge 9. It is provided.

The details of the device of the present invention will be explained below.

The air conditioning zone 1 is a space consisting of continuous rooms such as an IC manufacturing factory or other production line, a research institute, or a hotel kitchen. The air is circulated from there to the air conditioner 10 to condition the air conditioning zone 1.

A large number of draft chambers 2 are installed within the air conditioning zone 1, and these have shapes and structures suitable for the purpose of the air conditioning zone 1. In the present invention, exhaust equipment that has an inlet for sucking air in the zone, regardless of its shape and structure, is referred to as an exhaust port, hood, exhaust chamber, etc. This is a generic name for air conditioning zones that have a large number of such draft chambers. and,
These many draft chambers 2 are collected in an exhaust air duct 3 by system. FIG. 1 shows an example of two systems. This draft chamber 2 is shown in Figure 2.
An example (for laboratory use) is shown. In Figure 2,
20 is an opening/closing door, 21 is an inlet, 22 is an exhaust duct, and 23 is an orifice for adjusting a constant air volume or a damper for adjusting a constant air pressure. Each exhaust duct 22
is connected to the exhaust air duct 3, and one exhaust fan 4 is attached to each exhaust air duct 3 for each system. The exhaust fan 4 is driven by a variable speed motor 5, and the air volume is adjusted by controlling the rotational speed of the variable speed motor 5, as will be described later.

Usage status sensor 6 is installed in each draft chamber 2
In the case of a kitchen, it is a switch such as a flame eye that detects the presence or absence of a flame in a gas range, and in the case of a draft chamber in a factory or research institute, it is a switch as shown in Figures 3 to 5. Various switch mechanisms can be used, such as those shown in Figure 1. Figure 3 shows the front door 2 of the draft chamber.
Transmitted light type photoelectric switch 2 that detects the vertical opening and closing of 0
5 is used, and 26 is a bill shield plate. Figure 4 shows a roller leaf spring type micro switch 2 that similarly detects the vertical opening and closing of the front opening/closing door 20.
7 is used, and 28 is a backing plate. FIG. 5 similarly shows an example in which a magnetic type proximity switch 29 is used, and 30 indicates a magnet side component. Although these figures show examples in which the sensors are attached below the door, they can also be attached at the upper end of the door or other positions.

When the usage status of each draft chamber 2 is detected by the usage status sensor 6, the required air volume for each system is calculated in a computer such as a μ-computer. For example, when the draft chamber system number (j) and its address (i) are assigned and the usage status of all draft chambers is scanned, the required air volume for each system is calculated in the μ-computer.

Draft chamber usage status for each system Sij: 1 unit of O The unit required air volume of each draft chamber Vij: (m ³ /min unit) Then, the required air volume of No. 1 system R ₁ = ΣVi ₁ × Si ₁ ( m ³ /min) Required air volume for No. 2 system R ₂ =ΣVi ₂ ×Si ₂ (m ³ /min) In this way, the required air volume integrated for each system is transferred from the μ-computer output module to the controller. The signal is transmitted to the thyristor No. 7 and converted into a control signal of, for example, 4-20 mA (24 V) for the thyristor. This control signal is sent to the variable speed motor 5 to control its rotation speed. This controls the air volume of the exhaust fan 4. FIG. 6 shows an example of a block diagram of this μ-computer for air volume control. In FIG. 6, 31 is a μ-computer board, 32 is a thyristor (4 to 20 mA) or a frequency converter, 5 is a variable speed motor, and 6 is an exhaust fan. The air volume control program is EP-ROM
is written in. An example of this program is shown in FIG. Note that in order to prevent the exhaust fan from operating in the surging region when the number of draft chambers in use is extremely reduced, it is preferable to set a lower limit value in advance on the thyristor side.
If it is a holiday, press the stop button on the main control panel to
Shut off power to the computer and power to the variable speed motor.

Note that the transmission system between the usage status sensor 6 installed in each draft chamber 2 and the μ-computer can be configured as a multiplex transmission system to simplify the wiring work and wiring route, as shown in FIG. 8, for example. can. In FIG. 8, 2 is a draft chamber group, 6 is a usage status sensor, and 35
is a receiver, 36 is a two-core shielded wire, 37 is a transmitter, and 38 is a relay board. The transmitter 37 constantly scans the information of each receiver 35 and sends the usage status to the relay 38 on the control board. Let me keep it.

In this way, the required air volume for each system is delivered in accordance with the usage status of each draft chamber 2, and unnecessary discharge of air in the air conditioning zone is prevented. Then, due to fluctuations in usage conditions, the indoor balance is achieved by controlling the rotation speed or frequency of the fan motor 39 in the air conditioner in advance, but fluctuations in the static pressure difference between the air conditioning zone 1 and the perimeter zone 8 In order to prevent this from occurring, as shown in FIG.
Perform the opening adjustment in step 3. This letang damper 13
The opening degree is adjusted by a motor 40 that drives this. As a result, the amount of exhaust air can be controlled while controlling the indoor pressure.

According to the device of the present invention, IC manufacturing factories, research laboratories,
When a large amount of clean, constant temperature and humidity air is used in a hotel kitchen, etc., the exhaust of that air can be minimized, and at the same time, the amount of outside air processing can be reduced by that amount, resulting in annual outside air load processing costs and exhaust power costs. The total amount of air can be reduced to about 1/2 of that without controlling the exhaust air volume according to the usage status of the draft chamber, and an extremely energy-saving exhaust control system is provided.

[Brief explanation of drawings]

Fig. 1 is an overall view of the equipment layout showing an embodiment of the device of the present invention, Fig. 2 is a schematic sectional view showing an example of a draft chamber, and Figs. 3 to 5 are perspective views showing an example of a usage status sensor. , Figure 6 is a block diagram for controlling the air volume of the exhaust fan, Figure 7 is a program flow diagram for controlling the air volume of the exhaust fan, and Figure 8 is a system showing the transmission system between the usage status sensor and the μ-computer. It is a diagram. 1...Air conditioning zone, 2...Draft chamber, 3...Exhaust air duct, 4...Exhaust fan, 5...
Variable speed motor, 6...Usage status sensor, 7...
... Controller, 8 ... Perimeter zone, 9 ... Differential pressure gauge, 10 ... Air conditioner, 12 ... Lethane air duct, 13
...Retan damper.

Claims (1)

[Claims] 1. A large number of draft chambers installed in the air conditioning zone, an exhaust air duct installed so that each draft chamber communicates with the outside air, an exhaust fan installed in this exhaust air duct, and a device for driving this exhaust fan. A variable speed motor, a usage sensor for detecting the usage status of each draft chamber, a calculator that integrates the required exhaust air volume based on the signal from this usage status sensor, and the output signal from this calculator. a controller adapted to control the rotational speed or frequency of the variable speed motor; a differential pressure gauge for detecting the static pressure difference between the air conditioning zone and the surrounding building space; and an air conditioner suction from the air conditioning zone. An exhaust gas control device in an air-conditioning zone, comprising a rethan air duct installed so as to communicate with the side, and a rethan damper attached to the rethan air duct and whose opening degree is adjusted according to a signal from the differential pressure gauge.