JP5642050B2 - Constant temperature and humidity device - Google Patents

Description

  The present invention relates to a constant temperature and humidity apparatus, and more particularly to a constant temperature and humidity apparatus that adjusts an air atmosphere in which carbon dioxide gas or the like is adjusted to a low concentration in order to perform an environmental test.

  By introducing an air atmosphere in which carbon dioxide is adjusted to a low concentration into a constant temperature and humidity device, conditions of a lower concentration than the carbon dioxide concentration in the underground environment or the atmosphere can be realized in a simulated manner. By simulating the conditions of a lower concentration than the carbon dioxide concentration in the underground environment and the atmosphere, environmental tests such as durability of cement can be easily performed. In order to perform various environmental tests, it is desirable to control the carbon dioxide concentration to an arbitrary level.

  Various constant temperature and humidity devices that simulate the environment and perform tests have been proposed. For example, Patent Literature 1 proposes a constant temperature and humidity device that stably controls the temperature and humidity of air in a low temperature and high humidity state with high accuracy. In the device described in Patent Document 1, two constant temperature and humidity devices are connected by a duct, and one constant temperature and humidity device functions as a device that creates air having a target absolute temperature, and controls opening and closing of the duct. The air between the two constant temperature and humidity devices is circulated to adjust to the final target humidity.

JP 2010-230281 A

In the apparatus described in Patent Document 1, air adjusted to low concentration carbon dioxide (CO ₂ ) is not used, and air containing normal concentration carbon dioxide (CO ₂ ) is circulated. In such a device, in order to reduce the carbon dioxide concentration of the air to be circulated, it is necessary to dispose a gas removal device provided with an adsorbent that adsorbs oxygen dioxide in the circulation path.

  In addition, when air is circulated while removing carbon dioxide with a gas removal device, moisture in the air is also dehumidified, and the air is dried, which requires humidification.

  However, if the moisture in the air increases, the exhaustion of the adsorbent of the gas removal device becomes severe, causing problems such as frequent replacement of the adsorbent, etc., so carbon dioxide gas was adjusted to a low concentration It is not practical to apply to a constant temperature and humidity apparatus in an air atmosphere.

  An object of the present invention is to provide a constant temperature and humidity apparatus in an air atmosphere in which carbon dioxide gas is adjusted to a low concentration in order to solve the above-described problems.

  The constant temperature and humidity device of the present invention includes an airtight chamber, a gas supply means for supplying air containing carbon dioxide adjusted to a predetermined concentration into the airtight chamber, and a detection means for detecting the gas concentration of the air in the airtight chamber. A purge means capable of changing an amount of the air in the hermetic chamber to be purged to the outside, and a control means for controlling a purge amount of the purge means, wherein the control means has a leakage amount of air from the hermetic chamber The purge amount of the purge means is controlled according to the amount of gas supplied from the gas supply means.

  Further, the amount of air leakage may be calculated based on fluctuations in pressure in the hermetic chamber.

  And a valve means for adjusting the amount of gas supplied between the gas supply means and the hermetic chamber, and a gas concentration detection means for detecting a gas concentration in the hermetic chamber, wherein the carbon dioxide concentration in the hermetic chamber is constant. When the concentration is exceeded, the control means increases the amount of gas supplied from the valve means and increases the purge amount of the purge means, and the carbon dioxide concentration in the hermetic chamber is fed from the gas supply means. What is necessary is just to comprise so that it may adjust to below a fixed density | concentration above density.

  The gas supply means includes a gas purification device that generates air with a low concentration of carbon dioxide contained in the air, and a removal device that removes carbon dioxide contained in the air supplied from the gas purification device. And the like.

  Further, a compressor, an oil removal unit that removes oil in the air supplied from the compressor, and an air tank that injects air that has passed through the oil removal unit may be provided.

  The gas purifier includes a plurality of units, a gas supply line that supplies air from the gas purifier to the airtight chamber via the removal device, and a gas supply that supplies air from the gas purifier to the airtight chamber. And a gas supply line may be selected according to the state of air in the hermetic chamber.

  Further, humidification means, air conditioning means and temperature / humidity detection means are provided in the test chamber, and the control means controls the humidification means and air conditioning means in accordance with the output of the temperature / humidity detection means, and the test chamber has a predetermined temperature and What is necessary is just to comprise so that it may become humidity.

  According to this invention, by controlling the purge amount of the purge means according to the amount of air leakage from the test chamber and the amount of gas supplied from the gas supply means, and supplying air containing low concentration carbon dioxide, A constant temperature and humidity apparatus in an air atmosphere in which carbon dioxide gas is adjusted to a low concentration can be provided. In addition, since the carbon dioxide gas concentration in the constant temperature and humidity device can be set to an arbitrary concentration that is lower than the carbon dioxide concentration of air, various environmental tests can be easily performed.

It is a block diagram which shows the structure of the constant temperature and humidity apparatus concerning embodiment of this invention. It is a block diagram which shows an example of the gas supply line concerning embodiment of this invention. It is a schematic plan view which shows an example of the test chamber concerning embodiment of this invention. It is a side view which shows an example of the test chamber concerning embodiment of this invention. It is a typical perspective view which shows an example of the test chamber concerning embodiment of this invention. It is a principal part schematic sectional drawing for demonstrating the assembly of the panel concerning embodiment of this invention. It is a principal part schematic sectional drawing after assembling the panel concerning embodiment of this invention. It is a principal part schematic sectional drawing which shows the state which assembles the panel concerning embodiment of this invention on a floor. It is a block diagram which shows the front chamber part including the differential pressure | voltage damper concerning embodiment of this invention. It is a side view which shows the differential pressure | voltage damper concerning embodiment of this invention. It is a side view which shows the filter of the differential pressure | voltage damper concerning embodiment of this invention. It is a schematic sectional drawing which shows the differential pressure | voltage damper concerning embodiment of this invention. It is a schematic sectional drawing which shows the differential pressure | voltage damper concerning embodiment of this invention. It is a block diagram which shows an example of the gas supply line concerning other embodiment of this invention.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated in order to avoid duplication of description. FIG. 1 is a block diagram showing a configuration of a constant temperature and humidity apparatus according to an embodiment of the present invention.

As shown in FIG. 1, air containing carbon dioxide (CO ₂ ) adjusted to a predetermined concentration is supplied from a gas supply line 2 to a test chamber 1 constituted by an airtight chamber sealed from the outside. As will be described later, the test chamber 1 constitutes a constant temperature and humidity test chamber that maintains a predetermined temperature, humidity, and predetermined carbon dioxide concentration, and various environmental tests are performed in the chamber. The test chamber 1 has a size of 7 m × 11 m × 2.6 m, for example, and constitutes a test chamber 1 of a corresponding size by combining a plurality of heat insulating panels that do not transmit gas, as will be described later. . The test chamber 1 is provided with a front chamber 11 for a person to enter and exit, and a door 12 is provided between the front chamber 11 and the test chamber 1. When this door 12 is closed, the space between the test chamber 1 and the front chamber 11 is sealed. Further, the pressure in the test chamber 1 is set higher than the pressure in the front chamber 11 to prevent air in the front chamber 11 from entering the test chamber 1 from the front chamber 11.

  Further, the pressure in the front chamber 11 is set higher than the external pressure, and air is prevented from entering the front chamber 11 from the outside. The front chamber 11 is provided with a door 13 for a person to enter and exit. When this door 13 is closed, the exterior and the front chamber 11 are blocked.

A chamber purge damper 14 is provided between the test chamber 1 and the front chamber 11. The chamber purge damper 14 is constituted by, for example, an electric ball valve, and the purge amount is controlled from the damper by the control device 20 as will be described later. Furthermore, the differential pressure Dunbar 15 ₁ opens the valve when the test chamber 1 becomes equal to or higher than a predetermined pressure is provided between the test chamber 1 and the front chamber 11. Further, the differential pressure damper 15 ₂ opening the valve when even the front chamber 11 between the outdoor unit and the front chamber 11 becomes equal to or higher than a predetermined pressure is provided.

In this embodiment, between the front chamber 11 and the outside 10Pa～100Pa, preferably so as to maintain the pressure difference across 80 Pa, the differential pressure damper 15 ₂ is set. Further, between the front chamber 11 and test chamber 1 is also 1 0Pa～100Pa, preferably differential pressure damper 15 ₁ so as to maintain a pressure differential across 80Pa is set. Then, the air in the test chamber 1 is discharged from the chamber purge damper 14 into the front chamber 11 with a predetermined purge amount. The air despite being discharged by the chamber purge damper 14, the pressure differential between the test chamber 1 and the front chamber 11 exceeds 80Pa opening differential pressure damper 15 _1, the air in the test chamber 1 Is discharged into the front chamber 1. Furthermore, the pressure differential between the front chamber 11 and the test chamber 1 is less than 80Pa differential pressure damper 15 ₁ is closed.

The pressure differential between the front chamber 11 and the external differential pressure damper 15 ₂ is opened exceeds 80 Pa, the air in the front chamber 11 is discharged to the outside. Then, the pressure difference between the front chamber 11 and the outside becomes smaller than 80 Pa, the pressure difference damper 15 ₂ is closed.

  The gas supply line 2 is provided with two gas purifiers 21 and 22 for generating air with a low concentration of carbon dioxide contained in the air. The gas purifiers 21 and 22 include adsorbents such as silica gel, synthetic zeolite, and alumina gel. The air compressed by the compressor 25 removes oil in the air by the oil removal unit 26 and is injected into the air tank 27. The compressed air discharged from the air tank 27 is given to the gas purification apparatuses 21 and 22.

In the gas purification apparatuses 21 and 22, moisture and carbon dioxide are adsorbed by an adsorbent, and air containing low-concentration carbon dioxide is purified. In this embodiment, one gas purifier purifies 100 m ³ / Hr of gas. The purified gas is fed to the removal device 24 for further removal of carbon dioxide through the valve 23. The removal device 24 includes an adsorbent such as silica gel, synthetic zeolite, or alumina gel inside.

  In this embodiment, the gas purifiers 21 and 22 purify the air whose carbon dioxide concentration is adjusted to, for example, 10 ppm. In the removing device 24, the carbon dioxide is removed so that the concentration of carbon dioxide is, for example, 1 ppm or less and nearly 0 ppm, and the removed air is supplied into the test chamber 1.

  In the test chamber 1, a temperature / humidity sensor 16 for detecting the temperature and humidity in the test chamber 1, and a gas concentration sensor 17 for detecting the oxygen concentration and the gas concentration of carbon dioxide are provided. Detection outputs from these sensors 16 and 17 are given to a control device 20 having a computer. The test chamber 1 includes a humidifier 18 for adjusting indoor humidity and an air conditioner 19 for adjusting temperature.

  The control device 20 determines whether or not the carbon dioxide concentration in the test chamber 1 exceeds a certain concentration based on the detection output from the gas concentration sensor 17. In this embodiment, it is determined whether or not the concentration of carbon dioxide exceeds 5 ppm. When the concentration of carbon dioxide exceeds 5 ppm, the valve 23 is controlled to increase the amount of gas supplied. Then, the purge amount of the chamber purge damper 14 is increased to increase the air replacement amount in the test chamber 1. In this manner, the carbon dioxide concentration in the test chamber 1 is adjusted to 5 ppm or less, exceeding 0 ppm which is the concentration of carbon dioxide fed from the removing device 24.

  By the way, as shown in FIG. 5, the test chamber 1 in this embodiment is configured in a corresponding size by combining a plurality of heat insulating panels 120 that do not transmit gas. The panels 120 are assembled so that there is no gas leakage, but slight gas leakage occurs.

  Therefore, in the test chamber 1 of this embodiment, the purge amount of the gas discharged from the chamber purge damper 14 is set according to the amount of air leaked from the inside of the test chamber 1. That is, the amount of gas supplied from the gas supply line 2 and the amount of purge of gas discharged from the chamber purge damper 14 are the same as long as there is no leak from the room after the inside of the test chamber 1 is set to a predetermined pressure. Value.

  However, if there is a leak, purging the same amount as the gas supply amount, the air discharged from the test chamber 1 will be more than the supplied air, and the pressure will drop. Therefore, in this embodiment, the amount of air leakage in the test chamber 1 is calculated based on the change in the pressure in the test chamber 1, the gas purge amount is set based on the calculation result, and the purge of the chamber purge damper 14 is performed. Control the amount.

For example, if the leak amount in the test chamber 1 is calculated to be 5 m ³ / Hr after a predetermined pressure, the purge amount of the chamber purge damper 14 is set when the gas amount supplied from the gas supply line 2 is 20 m ³ / Hr. Set to 15 m ³ / Hr. In this manner, the air supplied into the test chamber 1 and the purged air of the chamber purge damper 14 are controlled, and the inside of the test chamber 1 is maintained at a predetermined pressure state.

  In addition, the air supplied from the gas supply line 2 is also removed from moisture when the carbon purifiers 21 and 22 and the removing device 24 remove carbon dioxide. For this reason, when the air in the test chamber 1 is replaced with the air supplied from the gas supply line 2, the humidity becomes lower than the predetermined humidity. In this embodiment, the inside of the test chamber 1 is maintained at a room temperature of 20 ° C. and a relative humidity (RT) of 60% to constitute a constant temperature and humidity test chamber 1. For this reason, the control device 20 calculates the humidity and temperature in the test chamber 1 based on the detection output from the temperature / humidity sensor 16. When the relative humidity becomes 60% or less, the control device 20 drives the humidifier 18 to humidify the inside of the test chamber 1 to maintain a predetermined humidity. Note that the water used in the humidifier 18 is pure water containing no impurities. Moreover, the control apparatus 20 is controlling the air conditioner 19 so that temperature may be set to 20 degreeC.

As described above, the temperature and humidity in the test chamber 1 are controlled. The air supplied to the test chamber 1 and the air purged by the chamber purge damper 14 are controlled so that the pressure in the test chamber 1 is also maintained at a predetermined pressure. By the way, it was found that the fluctuation of the pressure in the test chamber 1 is affected not only by the temperature change but also by the humidity change. That is, the air conditioner 19 operates to keep the temperature of the test chamber 1 at 20 ° C. At this time, it is dehumidified by the air conditioner 19. For example, the following is used as the air conditioner 19. The capacity of the air conditioner 19 varies up to 12 ° C. and relative humidity (RH) 95%, and the air volume is 280 m ³ / min.

Here, when the temperature changes from 20 ° C. and a relative humidity of 60% to a temperature of 10 ° C. and a relative humidity of 80%, dehumidification is about 3 g / m ³ . When the wind speed is applied, it is 821 g / min, which is 1.1 m ³ / min when converted into volume. Thus, the negative pressure of 1.1 m ³ / min is obtained when the refrigerator of the air conditioner 19 is started. The supply gas flow rate covering this negative pressure is 66 m ³ / Hr or more. The supply gas flow rate including the air speed of the air conditioner 19 needs to be about 100 m ³ / Hr. The test chamber 1 after gas replacement in low concentration CO _2, by supplying the dry low-concentration CO ₂ air 100 m 3 / ^Hr, it is possible to reduce the variation of pressure according to the running of the air conditioner 19.

  FIG. 2 is a block diagram showing an example of the gas supply line 2 according to the embodiment of the present invention. The gas supply line 2 will be described with reference to FIG.

The gas supply line 2 is provided with two gas purifiers 21 and 22 for generating air with a low concentration of carbon dioxide contained in the air. The gas purifiers 21 and 22 include adsorbents such as silica gel, synthetic zeolite, and alumina gel. In this embodiment, moisture and carbon dioxide are adsorbed by the adsorbent, and air containing low concentration carbon dioxide is purified. In this embodiment, the purification amount is 100 m ³ / Hr.

In this embodiment, the compressor 25 has two compressors 25 a and 25 b and is controlled by the control device 20 so as to be averaged and operated. By having the two compressors 25a and 25b, gas can be supplied without stopping the supply line 2 even if one compressor fails. The compressors 25a and 25b output compressed air of 210 m ³ / Hr at a pressure of 0.83 MPa. The air compressed by the compressor 25 is injected into an oil content removing unit 26 having a capacity of 100 L. After removing the oil content in the air, the air is injected into an air tank 27 having a capacity of 9.9 m ³ . Then, the compressed air discharged from the tank 26 is supplied to the gas purification apparatuses 21 and 22. In this embodiment, a flow rate valve 29 (29a, 29b) is provided between the air tank 27 and the gas purification devices 21 and 22 so that the amount of air given to the gas purification devices 21 and 22 can be adjusted. Yes.

  The gas purification devices 21 and 22 are connected to a removal device 24 having an adsorbent through a valve 23 a, and air from the gas purification devices 21 and 22 is given to the removal device 24. The removal device 24 of this embodiment has two adsorbents 24a and 24b inside. The adsorbents 24a and 24b are made of silica gel, synthetic zeolite, alumina gel, or the like.

The removal device 24 in this embodiment has a maximum capacity of 240 m ³ / Hr. As described above, the gas purifiers 21 and 22 purify a gas of 100 m ³ / Hr, so that the capacity of the removing device 24 is exceeded at the maximum output. For this reason, a line is provided from the lines of the gas purification devices 21 and 22 to the test chamber 1 via the valve 23b and not via the removal device 24. For example, in the startup state, it is necessary to quickly replace the air in the test chamber 1. In such a case, air containing carbon dioxide having a concentration of about 5 ppm is supplied into the test chamber 1 from both the line passing through the removal device 24 and the line not passing through the removal device 24. When the steady state or the steady state is approached, the valve 23b is closed, and air containing carbon dioxide having a concentration of 5 ppm or less exceeding 0 ppm is supplied via the removal device 24.

  In addition, air is supplied to the front chamber 11 from the gas purification apparatuses 21 and 22 through the valve 28.

  The air sent from the removing device 24 is configured so that the flow rate can be measured by the flow meter 30. Similarly, the air sent to the front chamber 11 can be measured by a flow meter 31.

  FIG. 3 is a schematic plan view showing an example of a test chamber according to the embodiment of the present invention, and FIG. 4 is a side view thereof. As shown in FIGS. 3 and 4, an air conditioner 19, a humidifier 18, a pure water generator 180 and the like are arranged in the test chamber 1 and are isolated from the outside. If the air conditioner 19 is arranged outside, there is a possibility that air leaks from the piping with the air conditioner 19.

  In this embodiment, it is necessary to maintain a low concentration of carbon dioxide. Therefore, since it is necessary to avoid the intrusion of the air from the outside and the leakage of the air to the outside as much as possible, the equipment 110 used for the test other than the gas supply line 2 is disposed in the test chamber 1. Air from the air conditioner 19 is supplied from a duct 190 provided on the ceiling. The suction port 191 is disposed in the vicinity of the device 110 used for the test, and the air conditioner 19 is circulated efficiently. The piping of the air conditioner 19 is performed between the ceiling provided in the test chamber 1 and the outer wall of the test chamber 1 and is isolated from the outside.

  Further, the test room 1 is provided with an emergency evacuation door 12a, and is configured to be able to escape directly from the door 12 without going through the front room 11 in an emergency.

  As described above, the test chamber 1 is configured to have a corresponding size by combining a plurality of heat insulating panels 120 that do not transmit gas. These panels 120 are assembled so that there is no gas leakage.

  An example of an assembly method for eliminating gas leakage between the panels 120 will be described with reference to FIGS. 6 is a schematic cross-sectional view of a main part for explaining the assembly of the panel according to the embodiment of the present invention, FIG. 7 is a schematic cross-sectional view of the main part after the assembly, and FIG. 8 is a state of assembling the panel on the floor. It is a principal part schematic sectional drawing shown.

  As shown in FIG. 6 and FIG. 7, the heat insulating panel 120 that does not transmit gas is configured by adhering surface members 120 a such as colored steel plates, antibacterial steel plates, stainless steel, and color aluminum to both surfaces of a core material 120 b such as hard urethane foam. Has been. The heat insulating panel 120 is provided with a female recess 121 and a male protrusion 122, respectively. Then, the female recess 121 and the male protrusion 122 are brought into contact with each other and assembled.

  As shown in FIG. 7, a barrier layer 124 made of epoxy resin, butyl rubber, a gas barrier film, or the like is provided at the joint of the panel 120. In this way, air leakage is prevented by providing the barrier layer 124.

  Next, an example of fixing the panel 120 to the floor 200 will be described with reference to FIG. As shown in FIG. 8, a self-tap anchor bolt 201 is attached to the floor 200, and the fixing hat fitting 130 h is attached using the self-tap anchor bolt 201. The panel support fitting 130b is attached to the fixing hat fitting 130h using bolts.

  The panel 120 is placed on the panel support fitting 130b, and a metal base board 130a is attached to the panel support fitting 130b so as to sandwich both side surfaces of the panel 120.

  A caulking material 132 made of epoxy resin, butyl rubber, or the like is applied between the panel 120 and the baseboard 130a so as to seal a gap between these members. Further, a caulking material 132 made of epoxy resin, butyl rubber or the like is also provided between the baseboard 130a and the floor 200.

  A coating 203 is applied to the surface of the floor 200 in the test chamber 1. On the floor 200 to which the coating 203 is applied, a caulking material 133 made of an epoxy resin is applied to a space between the coating 203 portion and the baseboard 130b, and the space between the baseboard 130a and the floor 200 to which the coating 203 is applied is applied. Is sealed. Butyl rubber may be used as a caulking material.

  As shown in FIG. 8, when the panel 120 is fixed to the floor 200 using the baseboard 130a, air leaks from the floor portion of the panel 120 by sealing with a caulking material such as epoxy resin or butyl rubber. Is suppressed.

Next, the amount of gas necessary for the test chamber of the present invention will be described. As the test chamber 1 having the above configuration, a test chamber having a size of 7.4 m × 11 m × 2.9 m was prepared. The amount of gas necessary to reduce the CO ₂ concentration in the test chamber 1 of this size is calculated based on the following equation, considering the recovery from the atmosphere to approximately 10 ppm to 20 ppm.

  V = (V0 / k) × ln (X0 / X)

Here, V is a required gas amount (m ³ ), X0 is 500 ppm (carbon dioxide concentration of the outside air standard), X is a target concentration (5 ppm), V0 is a volume to be replaced of 236.1 m ³ , and k is a replacement efficiency. (0.6 to 0.8).

From the above equation, V = (236.1 / 0.6) × ln (500/5) = 1812 m ³ .

In order to replace the inside of the test chamber 1 of the above size from the outside air standard state to the low CO ₂ concentration environment, the same amount of gas as the gas supply amount is purged. The gas replacement in the test chamber 1 was confirmed by changing the gas flow rate. The gas concentration in the test chamber 1 is measured when the flow rate of the low-concentration CO ₂ gas is changed to 40 m ³ / Hr, 80 m ³ / Hr, 100 m ³ / Hr, 120 m ³ / Hr, and the state of gas replacement is examined. It was.

From the above calculation formula, it can be estimated how long the air in the test chamber 1 can be replaced at each flow rate. When the flow rate of the low-concentration CO ₂ gas is 40 m ³ / Hr, the gas concentration does not decrease so much even after 1 hour, and it is possible that the gas is back-diffused.

It was confirmed that when the flow rate of the low-concentration CO ₂ gas was 80 m ³ / Hr, the gas concentration gradually decreased. However, it was found that the decrease in gas concentration was very slow.

When the flow rate of the low-concentration CO ₂ gas was 100 m ³ / Hr, it was confirmed that the gas concentration was reliably reduced. In addition, when the flow rate of the low concentration CO ₂ gas was 120 m ³ / Hr, it was confirmed that the gas concentration was further rapidly decreased and the concentration became about 5 ppm in about 115 minutes. From this, it was found that the gas flow rate is preferably 100 m ³ / Hr or more.

Next, the differential pressure dampers 15 ₁ and 15 ₂ provided between the test chamber 1 and the front chamber 11 and between the front chamber 11 and the outside of the room will be described with reference to FIGS.

As described above, the chamber purge damper 14 is provided between the test chamber 1 and the front chamber 11. The chamber purge damper 14 is composed of, for example, an electric ball valve, and the purge amount is controlled from the damper 14 by the control device 20 as will be described later. Furthermore, the differential pressure Dunbar 15 ₁ opens the valve when the test chamber 1 becomes equal to or higher than a predetermined pressure is provided between the test chamber 1 and the front chamber 11. Further, the differential pressure damper 15 ₂ opening the valve when even the front chamber 11 between the outdoor unit and the front chamber 11 becomes equal to or higher than a predetermined pressure is provided.

In this embodiment, between the front chamber 11 and the outdoor unit 10Pa～100Pa, preferably so as to maintain the pressure difference across 80 Pa, the differential pressure damper 15 ₂ is set. Further, between the front chamber 11 and test chamber 1 is also 10Pa～100Pa, preferably differential pressure damper 15 ₁ so as to maintain a pressure differential across 80Pa is set. Further, the air in the test chamber 1 is discharged from the chamber purge damper 14 into the front chamber 11 with a predetermined purge amount.

A filter 15f is attached to each of the differential pressure dampers 15 ₁ and 15 ₂ . As shown in FIGS. 10 to 13, the differential pressure dampers 15 ₁ and 15 ₂ are provided with a duct hole 15h in the main body case 150, and a blade member 15g that opens and closes by pressure is attached to the hole 15h. The blade member 15g is slidably attached to a shaft 15c provided at the center of the main body. A weight 15a for adjusting the differential pressure is attached to the blade member 15g by a weight presser 15b. The blade member 15g is provided with a holding packing 15p that abuts around the duct hole 15h of the main body.

As shown in FIG. 13, when the pressure difference is 80Pa smaller than, by weight 15a for differential pressure control, pressing the packing 15p of the blade member 15g is brought into contact with the periphery of the hole 15h duct differential pressure damper 15 ₁ , 15 ₂ are closed. When the pressure difference exceeds 80 Pa, as shown in FIG. 12, the blade member 15g moves along the shaft 15c against the differential pressure adjusting weight 15a, and the differential pressure dampers 15 ₁ and 15 ₂ open. . When the differential pressure dampers 15 ₁ and 15 ₂ are opened, the indoor exhaust port is made small so that the air speed does not change so much between the air around the shaft 15c and the periphery of the duct hole 15h. Measures such as doing are taken.

  FIG. 14 is a block diagram showing an example of a gas supply line 2 according to another embodiment of the present invention. The gas supply line 2 will be described with reference to FIG.

  In the embodiment described above, the gas supply line 2 is configured so as to keep the inside of the test chamber 1 at a low concentration of carbon dioxide of about 5 ppm. On the other hand, in the embodiment shown in FIG. 14, the inside of the test chamber 1 is maintained at a required carbon dioxide concentration from a low carbon dioxide concentration of about 5 ppm to a carbon dioxide concentration slightly lower than the outside air standard. It is comprised as follows.

  Basically, it is the same as the gas supply line 2 shown in FIG. 2 described above, but in this embodiment, oil in the air is removed from the air tank 27 in order to control the carbon dioxide concentration close to the outside air standard. In order to supply the compressed air into the test chamber 1, a gas supply line is added between the test chamber 1 and the air tank 27 via the valve 32. Since other configurations are the same as those in FIG. 2, the same components are denoted by the same reference numerals, and description thereof is omitted here.

  When the test chamber 1 is controlled to a concentration higher than the concentration of carbon dioxide contained in the air supplied from the gas purifiers 21 and 22, the valve 32 is opened as necessary and the outside air standard is set in the air tank 27. Air having a carbon dioxide concentration of about 300 ppm to 550 ppm is supplied into the test chamber 1. When the inside of the test chamber 1 is controlled to a desired carbon dioxide concentration, the valve 32 is closed and air is supplied from the gas purification apparatuses 21 and 22.

  According to the carbon dioxide concentration in the test chamber 1, the valves 23a, 23b and the valve 32 are controlled to switch the air supplied to the test chamber 1, and the test chamber 1 is changed from a low concentration of carbon dioxide of about 5 ppm. Maintain the required carbon dioxide concentration up to a slightly lower carbon dioxide concentration than the outside air standard.

  In the above-described embodiment, the airtight chamber is applied to a test chamber for performing various environmental tests. However, the present invention can also be applied to a constant temperature and humidity chamber other than the environmental test chamber. For example, the present invention can be applied to a dry room or a clean room.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims for patent.

DESCRIPTION OF SYMBOLS 1 Test chamber 2 Gas supply line 11 Front chamber 12, 13 Door 14 Chamber purge damper 15 ₁ , 15 ₂ Differential pressure damper 16 Temperature / humidity sensor 17 Gas concentration sensor 18 Humidifier 19 Air conditioner 20 Control device 21, 22 Gas purification device 23 , 28 Valve 24 Removal device 25 Compressor 26 Air tank 27 Oil content removal unit

Claims (6)

An airtight chamber,
Gas supply means for supplying air containing carbon dioxide adjusted to a predetermined concentration into the hermetic chamber;
Detecting means for detecting a gas concentration of air in the hermetic chamber;
Purge means capable of changing the amount of air purged to the outside in the hermetic chamber;
A differential pressure damper that maintains a predetermined pressure in the hermetic chamber;
Valve means for adjusting the amount of gas supplied between the gas supply means and the hermetic chamber;
Gas concentration detecting means for detecting the gas concentration in the hermetic chamber;
Control means for controlling the purge amount of the purge means,
The gas supply means includes: a gas purification device that generates air with a low concentration of carbon dioxide contained in air; and a removal device that removes carbon dioxide contained in the air supplied from the gas purification device. Have
The control means controls the purge amount of the purge means according to the amount of air leakage from the hermetic chamber and the amount of gas supplied from the gas supply means,
When the carbon dioxide concentration in the hermetic chamber exceeds a certain concentration, the control means increases the amount of gas supplied from the valve means and increases the purge amount of the purge means, thereby reducing the carbon dioxide concentration in the hermetic chamber. A constant temperature and humidity apparatus that adjusts the carbon dioxide concentration fed from the gas supply means to be equal to or greater than the carbon dioxide concentration and equal to or less than a certain concentration . The gas purification device includes a plurality of units, a gas supply line that supplies air from the gas purification device to the airtight chamber via the removal device, and a gas supply line that supplies air from the gas purification device to the airtight chamber; the a, in accordance with the air in the state of the airtight chamber, the gas supply line is selected, constant temperature and humidity device according to claim 1. The constant temperature and humidity apparatus according to claim 1 or 2, wherein the air leakage amount is calculated based on a change in pressure in the hermetic chamber. A compressor; an oil removal unit that removes oil in the air supplied from the compressor; and an air tank that injects air that has passed through the oil removal unit, and supplies air from the air tank to the gas purification device. The constant temperature and humidity apparatus of any one of Claim 1 thru | or 3 . The constant temperature and humidity apparatus according to claim 4 , further comprising a gas supply line for supplying air from the air tank to the hermetic chamber. Humidification means, air conditioning means, and temperature / humidity detection means are provided in the airtight chamber, and the control means controls the humidification means, air conditioning means in accordance with the output of the temperature / humidity detection means, so that the airtight chamber has a predetermined temperature and The constant temperature and humidity device according to any one of claims 1 to 5 , wherein the device is humidity.

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