Environmental formation apparatus and environmental formation method

Abstract

To adjust a water vapor flow rate to be introduced into an environment formation tank while suppressing a response lag.SOLUTION: An environment formation device 10 comprises: an environment formation tank 12 which has an environment formation chamber 18 for forming a prescribed humidity environment; a vapor generator 14 which has a water storage tank 31 and a heater 32 and generates water vapor by heating water stored in the water storage tank 31 by a heater 32; a pipeline 16 which connects the environment formation tank 12 with the vapor generator 14; a motor valve 38 which is provided in the pipeline 16; a humidity detector 28 for acquiring the humidity of an environment formation chamber 18; and a controller 45 which controls the heater 32 and the motor valve 38. The controller 45 executes control of changing the opening degree of the motor valve 38 on the basis of the humidity acquired by the humidity detector 28 in the humidity operation of controlling the humidity in the environment formation chamber 18.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an environment forming apparatus and an environment forming method.

Background Art

[0002] Conventionally, an environment forming apparatus for forming a predetermined humidity environment is known. In the environment forming apparatus, as a configuration for forming a predetermined humidity environment, there are a humidifying dish type in which a water vapor generation mechanism is provided in an environment forming tank, and a humidifying boiler type in which a water vapor generation mechanism is provided outside the environment forming tank. The humidifying dish type is mainly used for a small-sized environment forming apparatus because the amount of generated water vapor is small. On the other hand, the humidifying boiler type is used for a large-sized environment forming apparatus that requires a large amount of water vapor.

[0003] An example of an environment forming apparatus using a water vapor generation mechanism of the humidifying boiler type is disclosed in Patent Document 1 below. The environment forming apparatus disclosed in this document includes an environment forming tank having an environment forming chamber, a water storage tank and a heater, a steam generator disposed outside the environment forming apparatus, and a pipe connecting the steam generator and the environment forming tank to each other. Then, water stored in the water storage tank is heated by a heater to generate water vapor, and this water vapor is caused to flow into the environment forming tank through the pipe. Thereby, the inside of the environment forming tank can be humidified.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] While Patent Document 1 does not disclose how to control the humidity inside the environmental formation chamber, in this environmental formation apparatus, when controlling the humidity inside the environmental formation chamber, a method can be adopted in which the heater of the steam generator is controlled according to the required amount of humidification. In this case, a method can be adopted in which the heater output is controlled using the detection result of a humidity sensor installed in the environmental formation tank. However, when humidity is controlled by controlling the heater output, there is a risk of response delay. That is, since the water storage tank is generally used in large environmental formation tanks that require a large amount of water vapor, both the water volume and heater capacity are large. Also, since the water storage tank that can store a large amount of water is located away from the environmental formation tank, the piping also becomes long. Furthermore, since the heat output of the heater and the amount of steam generated are not necessarily in a linear relationship, even if the humidity inside the environmental formation tank is detected by a humidity sensor, it is difficult to control the amount of steam generated accurately when controlling the heater output based on the detection result. Due to these factors, there is a risk of response delay.

[0006] Therefore, the present invention has been made in view of the above-mentioned prior art, and its objective is to enable the adjustment of the water vapor flow rate introduced into the environment formation tank while suppressing response delay. [Means for solving the problem]

[0007] To achieve the above objective, the environmental formation apparatus according to the present invention comprises: an environmental formation tank having an environmental formation chamber for forming a predetermined humidity environment; a steam generator having a water storage tank and a heater, configured to generate steam by heating the water stored in the water storage tank with the heater; piping connecting the environmental formation tank and the steam generator; an electric valve provided in the piping; a humidity detector for acquiring the humidity of the environmental formation chamber; and a controller configured to control the heater and the electric valve. In humidity operation for controlling the humidity in the environmental formation chamber, the controller performs control to change the opening degree of the electric valve based on the humidity acquired by the humidity detector. Furthermore, before starting the humidity operation to control the humidity in the environmental formation chamber, the heater is controlled to generate water vapor in the water storage tank and the electric valve is controlled to prevent or minimize the flow of the generated water vapor into the environmental formation tank. At the start of the humidity operation, the electric valve is controlled to allow the generated water vapor to flow into the environmental formation tank. .

[0008] In this invention, the flow rate of steam introduced into the environmental formation tank through piping can be changed by changing the opening degree of an electric valve. Since the electric valve is installed in the piping connecting the environmental formation tank and the steam generator, it is located closer to the environmental formation tank than the water storage tank. For this reason, the configuration that adjusts the opening degree of the electric valve can change the flow rate of steam introduced into the environmental formation tank more quickly than the configuration that adjusts the amount of steam generated in the water storage tank. Moreover, in the configuration that adjusts the amount of steam generated by adjusting the heater output of the water storage tank, there is a possibility of response delay due to the influence of the water volume stored in the water storage tank, but in the configuration that adjusts the flow rate of steam introduced into the environmental formation tank by adjusting the opening degree of the electric valve, such a response delay does not occur. Furthermore, in a configuration where the amount of steam generated is adjusted by adjusting the heater output of the water storage tank, the relationship between the heat output of the heater and the amount of steam generated is not necessarily linear, making it difficult to control the timing of generating a predetermined amount of steam. However, in a configuration where the flow rate of steam introduced into the environmental formation tank is adjusted by adjusting the opening degree of an electric valve, the flow rate of steam can be controlled according to the opening degree of the electric valve. Therefore, it is easier to control the timing of introducing steam into the environmental formation tank. Accordingly, in the present invention, it is possible to adjust the flow rate of steam introduced into the environmental formation tank while suppressing response delay.

[0010] Also Before starting the humidity operation, which controls the humidity inside the environmental formation chamber, water vapor is generated in the water tank. However, although the water vapor generated by this steam generator flows into the piping, it does not pass through the electric valve, or hardly passes through it at all. Therefore, the generated water vapor does not flow into the environmental formation tank, or hardly flows into it at all. Then, at the start of the humidity operation, the water vapor is introduced into the environmental formation tank. At this time, the water vapor is already present up to the electric valve, so the electric valve can be controlled to introduce the water vapor into the environmental formation tank at the right time. Therefore, even when starting the humidity operation, the response delay of the humidity control can be suppressed. Note that "at the start of the humidity operation" includes introducing water vapor at at least one of the following times: immediately after starting the humidity operation, at the time of starting, and immediately before starting. The environmental formation apparatus according to the present invention comprises an environmental formation tank having an environmental formation chamber for forming a predetermined humidity environment; a steam generator having a water storage tank and a heater, configured to generate steam by heating the water stored in the water storage tank with the heater; piping connecting the environmental formation tank and the steam generator; an electric valve provided in the piping; a pressure detector for detecting the pressure in the piping or the water storage tank; a humidity detector for obtaining the humidity of the environmental formation chamber; and a controller configured to control the heater and the electric valve. In humidity operation for controlling the humidity in the environmental formation chamber, the controller performs control to change the opening degree of the electric valve based on the humidity obtained by the humidity detector, and controls the heater so that the pressure detected by the pressure detector becomes a predetermined pressure.

[0011] The controller may be configured to control the electric valve to gradually increase its opening degree when the humidity operation starts, and then transition to controlling the opening degree of the electric valve based on the humidity acquired by the humidity sensor.

[0012] In this embodiment, it is possible to prevent a sudden change in the amount of steam generated due to a rapid change in the pressure inside the water storage tank as the opening of the electric valve is increased. For example, if the opening of the electric valve is rapidly increased so that steam flows into the environmental formation tank, there is a risk that the water stored in the water storage tank may boil over. However, by gradually increasing the opening of the electric valve, boiling over can be prevented. Therefore, it is possible to prevent a sudden increase in the amount of steam generated.

[0013] The controller may be configured to switch to controlling the opening degree of the electric valve based on the humidity acquired by the humidity detector when the humidity operation starts.

[0014] In this embodiment, for example, when the steam generator is not a sealed structure and the pressure inside the water tank does not change rapidly even when the opening of the electric valve is rapidly increased, it is possible to suppress the boiling of the water stored in the water tank. Therefore, the control of the electric valve opening based on the detection result of the humidity sensor can be started earlier.

[0015] The controller may control the heater during the humidity operation so that the water temperature in the water tank remains constant.

[0016] In this embodiment, the water temperature in the reservoir is kept constant during humidity operation, thus stabilizing the amount of water vapor generated during humidity operation. Therefore, the relationship between the opening degree of the electric valve and the amount of water vapor flowing into the environmental formation tank can be stabilized. Consequently, humidity control during humidity operation can be performed more accurately.

[0017] A relief valve may be provided at a portion of the pipe on the side of the water storage tank with respect to the motorized valve in the pipe. In this aspect, it is possible to prevent the pressure in the pipe from excessively rising. Therefore, the pressure in the pipe on the upstream side of the motorized valve can be stabilized.

[0018] The environmental formation method according to the present invention is an environmental formation method for forming a predetermined humidity environment in an environmental formation chamber in an environmental formation tank. In a steam generator disposed outside the environmental formation tank, water stored in a water storage tank is heated by a heater to generate steam, the humidity of the environmental formation chamber is acquired by a humidity detector, and a humidity operation for controlling the humidity in the environmental formation chamber Before starting the operation, the heater is controlled so that steam is generated in the water tank, and the electric valve installed in the piping connecting the environmental formation tank and the steam generator is controlled so that the generated steam does not flow into the environmental formation tank or hardly flows in at all, and when the humidity operation starts, the electric valve is controlled so that the generated steam flows into the environmental formation tank, and the humidity operation in which, based on the humidity acquired by the humidity detector, the Electrical Recording opening degree of the motorized valve is adjusted to adjust the humidity in the environmental formation chamber. The present invention relates to an environmental formation method for forming a predetermined humidity environment in an environmental formation chamber within an environmental formation tank, wherein a steam generator located outside the environmental formation tank generates steam by heating water stored in a water storage tank with a heater, the humidity of the environmental formation chamber is obtained by a humidity detector, and the pressure in the piping connecting the environmental formation tank and the steam generator or the pressure in the water storage tank is detected by a pressure detector. In a humidity operation for controlling the humidity in the environmental formation chamber, the opening degree of an electric valve provided in the piping is adjusted based on the humidity obtained by the humidity detector, and the heater is controlled so that the pressure in the piping or the pressure in the water storage tank becomes a predetermined pressure, thereby adjusting the humidity in the environmental formation chamber.

Advantages of the Invention

[0019] As described above, according to the present invention, it is possible to adjust the flow rate of steam introduced into the environmental formation tank while suppressing the response delay.

Brief Description of the Drawings

[0020] [Figure 1] It is a diagram schematically showing the overall configuration of the environmental formation apparatus according to the present embodiment. [Figure 2] It is a diagram for explaining the environmental formation method by the environmental formation apparatus.

Embodiments for Carrying Out the Invention

[0021] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

[0022] As shown in FIG. 1, the environmental formation device 10 according to the present embodiment is configured as an environmental test device that maintains the environmental formation chamber at a predetermined temperature and humidity and conducts an environmental test in which a specimen placed in the environmental formation chamber is exposed to this temperature and humidity environment. The environmental formation device 10 includes an environmental formation tank 12 configured as a constant temperature and humidity tank, a steam generator 14, and a pipe 16 connecting the two.

[0023] The environmental formation tank 12 has an environmental formation chamber 18 for forming a predetermined temperature and humidity environment and an air conditioning chamber 19 adjacent to the environmental formation chamber 18. The environmental formation chamber 18 and the air conditioning chamber 19 are integrally formed by a heat insulating wall, and the environmental formation chamber 18 and the air conditioning chamber 19 are adjacent to each other via a partition wall 20.

[0024] In the air conditioning chamber 19, an air conditioner for generating conditioned air to set the inside of the environmental formation chamber 18 to a predetermined temperature and humidity is arranged. This air conditioner includes a heater 22 for heating air, a cooler 23 for cooling air, an outlet 24 for discharging the water vapor introduced from the steam generator 14, and a blower 25 for blowing the conditioned air in the air conditioning chamber 19 into the environmental formation chamber 18.

[0025] The environmental formation chamber 18 has a size capable of arranging a specimen, and an entrance / exit 18a for the specimen is provided.

[0026] The environmental formation tank 12 is equipped with a temperature detector 27 that acquires the temperature inside the environmental formation chamber 18 and a humidity detector 28 that acquires the humidity inside the environmental formation chamber 18. The temperature detector 27 is composed of a temperature sensor. The temperature detector 27 may be placed inside the environmental formation chamber 18 to directly detect the temperature inside the environmental formation chamber 18, or it may be placed inside the air conditioning chamber 19 to estimate the temperature inside the environmental formation chamber 18 from the temperature inside the air conditioning chamber 19, as long as it can acquire the temperature of the air inside the environmental formation chamber 18. The humidity detector 28 is composed of a humidity sensor. The humidity detector 28 may be placed inside the environmental formation chamber 18 to directly detect the humidity inside the environmental formation chamber 18, as long as it can acquire the humidity of the air inside the environmental formation chamber 18, or it may be placed inside the air conditioning chamber 19 to estimate the humidity inside the environmental formation chamber 18 from the humidity inside the air conditioning chamber 19, as long as it can acquire the humidity of the air inside the environmental formation chamber 18.

[0027] The steam generator 14 includes a water storage tank 31 for storing water, a heater 32 for heating the water stored in the water storage tank 31, a water level gauge 33 for detecting the water level, and a water thermometer 34 for detecting the water temperature. When the heater 32 is activated, the water in the water storage tank 31 evaporates, generating steam. The water storage tank 31 may be a sealed structure, or it may be a non-sealed structure configured to overflow when the stored water exceeds a predetermined amount. The water level gauge 33 is optional.

[0028] The piping 16 connects the steam generator 14 and the environment formation tank 12 so that steam generated in the water storage tank 31 can be introduced into the air conditioning room 19. The end of the piping 16 opens into the air conditioning room 19 as the outlet 24 described above.

[0029] An electric valve 38 is provided in the piping 16. The electric valve 38 is preferably positioned as close to the outlet 24 as possible, and it is desirable that it be positioned such that the distance from the environmental formation tank 12 is shorter than the distance from the water storage tank 31.

[0030] The electric valve 38 is a type of valve whose opening degree can be changed to any desired degree. Changing the opening degree of the electric valve 38 changes the opening area of ​​the piping 16, and thus changes the flow rate of water vapor passing through the electric valve 38. Therefore, the flow rate of water vapor flowing from the water storage tank 31 to the environmental formation tank 12 is adjusted according to the opening degree of the electric valve 38. When the electric valve 38 is closed, the space between the water storage tank 31 and the environmental formation tank 12 is blocked, so water vapor in the water storage tank 31 cannot flow into the environmental formation tank 12.

[0031] A pressure sensor 41 and a relief valve 42 are provided in the piping 16 upstream of the electric valve 38, that is, on the steam generator 14 side of the electric valve 38. The pressure sensor 41 is configured to detect the steam pressure upstream of the electric valve 38. The relief valve 42 is configured to release steam in the piping 16 when the pressure in the piping 16 upstream of the electric valve 38 exceeds a set value. Note that the pressure sensor 41 may be provided in the steam generator 14 instead of the piping 16, and the relief valve 42 may also be provided in the steam generator 14 instead of the piping 16.

[0032] The temperature sensor 27, humidity sensor 28, air conditioner, electric valve 38, pressure sensor 41, water thermometer 34, and heater 32 are electrically connected to the controller 45. The controller 45 consists of a computer configured to control various operations of the constant temperature and humidity chamber, and the functions of the controller 45, executed by the central processing unit (CPU) of this computer, include a temperature and humidity setting unit 45a, a temperature control unit 45b, a heater control unit 45c, and a valve control unit 45d.

[0033] The temperature and humidity setting unit 45a is a functional unit for setting the temperature and humidity of the environmental formation chamber 18, and it is possible to set only the temperature or to set both the temperature and humidity. In this embodiment, for example, a temperature operation that controls only the temperature is performed as the first operation, and in the subsequent second operation, a humidity operation that controls both the temperature and humidity is performed. Therefore, a first operation in which a certain temperature is set as the set temperature is registered, and a second operation in which a certain temperature and a certain humidity are set as the set temperature and set humidity are also registered.

[0034] The temperature control unit 45b controls the heater 22 and cooler 23 so that the temperature detected by the temperature sensor 27 becomes the set temperature set by the temperature and humidity setting unit 45a. The temperature control unit 45b controls the heater 22 and cooler 23 to match the set temperature for the first operation for the duration set for the first operation, and then controls the heater 22 and cooler 23 to match the set temperature for the second operation for the duration set for the second operation.

[0035] The heater control unit 45c is configured to control the heater 32 in the second operation (humidity operation) based on the measurement results of the water thermometer 34. That is, the heater control unit 45c adjusts the output of the heater 32 so that the temperature of the water stored in the water tank 31 reaches a predetermined temperature. As a result, the water temperature in the water tank 31 is maintained at a constant temperature, and a predetermined amount of water vapor can be generated. This predetermined temperature may be the boiling point of water, or it may be a temperature slightly lower than the boiling point. This is because water vapor will be generated from the water in the water tank 31 even if the temperature is below the boiling point.

[0036] The heater control unit 45c activates the heater 32 prior to humidity operation when humidity operation is performed. That is, since the temperature and humidity setting unit 45a registers a second operation with set temperature and humidity, the heater control unit 45c activates the heater 32 before starting the second operation. This allows water vapor to flow into the piping 16 before humidity operation starts. In this embodiment, the first operation is also registered, so the heater 32 is activated at the start of the first operation or during the first operation. In controlling the heater 32 during the first operation, the heater output is controlled in the same way as in controlling the heater 32 during the second operation, so that the temperature of the water stored in the water tank 31 remains constant. Note that the control of the heater 32 may be performed over the entire period of the first operation, but this is not necessarily required; it is sufficient to perform it for at least a portion of the first operation. In short, the heater 32 should be controlled so that a predetermined amount of water vapor is ready at the time the humidity operation starts.

[0037] Furthermore, when the heater control unit 45c controls the heater 32 to maintain a constant water temperature, if the steam pressure detected by the pressure sensor 41 exceeds a predetermined pressure, it reduces the capacity of the heater 32. This prevents the pressure inside the piping 16 from becoming excessively high.

[0038] The valve control unit 45d is configured to control the electric valve 38 in humidity operation (second operation) based on the humidity acquired by the humidity detector 28. That is, the valve control unit 45d controls the opening degree of the electric valve 38 so that the humidity acquired by the humidity detector 28 becomes the humidity set by the temperature and humidity setting unit 45a.

[0039] Furthermore, at the start of the second operation, the valve control unit 45d controls the electric valve 38 to gradually increase its opening degree. That is, the valve control unit 45d adjusts the opening degree of the electric valve 38 while detecting the pressure (pressure in the piping 16 or water tank 31) using the pressure sensor 41. If the detected pressure does not drop below a predetermined pressure when the opening degree is increased by a predetermined degree, the electric valve 38 is controlled to gradually increase the opening degree by increasing it by the predetermined degree again. At this time, a limit value may be set for the amount of change in the opening degree per predetermined time, and the opening degree may be changed within the range of this limit value.

[0040] Here, an environmental formation method for forming a predetermined humidity environment in the environmental formation chamber 18 using the environmental formation device 10 will be explained with reference to Figure 2. In this embodiment, a temperature operation (first operation) is performed to control only the temperature, followed by a humidity operation (second operation) that controls both temperature and humidity. Therefore, the environmental formation method in this case will be explained here.

[0041] First, the temperature and humidity are set (step ST11). In this step, the test temperature for the first operation and the test temperature and humidity for the second operation are set. Therefore, the set temperature for the first operation is input through an input device (not shown in the diagram), and the set temperature and humidity for the second operation are also input through an input device (not shown in the diagram). As a result, the set temperature for the first operation is stored in the controller 45, and the set temperature and humidity for the second operation are also stored in the controller 45. At this time, the test time for the first operation and the test time for the second operation are also set.

[0042] After the test specimen is placed in the environmental formation chamber 18, the controller 45 starts the first operation when it receives a test start command (step ST12). During the first operation, the heater 22 and cooler 23 are controlled and the blower 25 is activated so that the temperature detected by the temperature sensor 27 becomes the set temperature for the first operation, causing conditioned air to circulate within the environmental formation chamber 18 and the air conditioning chamber 19. This adjusts the temperature inside the environmental formation chamber 18 to the set temperature. The first operation continues for the set test time.

[0043] In this first test, steam is generated in the steam generator 14 (step ST13). That is, the heater 32 of the steam generator 14 is activated to heat the water in the water storage tank 31. As a result, steam is generated in the water storage tank 31, and this steam also flows into the piping 16. However, since the electric valve 38 is closed during the first test, the steam does not flow beyond the electric valve 38. This ensures that steam is present up to the electric valve 38 before starting humidity operation.

[0044] During the first test, when generating steam, the heater 32 is controlled so that the water temperature measured by the water thermometer 34 remains constant, but constant water temperature control is not always necessary. At this time, the electric valve 38 may be completely closed, but if very little steam passes through the electric valve 38, it may be left slightly open.

[0045] Once the test time for the first operation has elapsed, the system moves to the second operation (step ST14). In the second operation, humidity control is performed, and the heater 22, cooler 23, motor valve 38, and heater 32 are controlled so that the temperature and humidity inside the environment formation chamber 18 reach the set temperature and humidity.

[0046] In the second operation, a transition operation is first performed in which the opening degree of the electric valve 38 is gradually increased, and then a control operation is performed in which the opening degree of the electric valve 38 is adjusted based on the humidity acquired by the humidity detector 28. That is, at the start of humidity operation, there is a possibility that the humidity in the environment formation chamber 18 will change rapidly, and in that case, the opening degree of the electric valve 38 is gradually increased so that the pressure in the water storage tank 31 does not fluctuate rapidly when the electric valve 38 is opened. At this time, the pressure detector 41 detects the pressure (pressure in the piping 16 or water storage tank 31), and if the detected pressure does not drop below a predetermined pressure when the opening degree of the electric valve 38 is increased by a predetermined opening degree, the opening degree is increased again by the predetermined opening degree, and this is repeated to gradually increase the opening degree. When the opening degree of the electric valve 38 is based on the difference between the humidity acquired by the humidity detector 28 (acquired humidity) and the set humidity, the operation transitions to control operation. From this point onward, the opening degree of the electric valve 38 is controlled by feedback control (e.g., PID control) based on the difference between the acquired humidity and the set humidity. In other words, when increasing humidity, the electric valve 38 is controlled to increase its opening degree as the difference between the acquired humidity and the set humidity increases. As a result, the flow rate of water vapor introduced into the environmental formation tank 12 increases in accordance with the change in the opening degree. On the other hand, when the difference between the acquired humidity and the set humidity decreases, the electric valve 38 is controlled to decrease its opening degree. As a result, the flow rate of water vapor introduced into the environmental formation tank 12 decreases in accordance with the change in the opening degree. This adjusts the humidity in the environmental formation chamber 18 so that the acquired humidity measured by the humidity sensor 28 approaches the set temperature.

[0047] In the second operation, the heater 32 is controlled so that the water temperature measured by the water thermometer 34 remains constant. As a result, the amount of steam generated in the water storage tank 31 is stable, and the relationship between the opening degree of the electric valve 38 and the amount of steam flowing into the environmental formation tank 12 is also stable. However, even in the second operation (controlled operation), it is not always necessary to maintain constant water temperature control.

[0048] As explained above, in this embodiment, the flow rate of steam introduced into the environmental formation tank 12 through the piping 16 can be changed by changing the opening degree of the electric valve 38. Since the electric valve 38 is installed in the piping 16 that connects the environmental formation tank 12 and the steam generator 14, it is located closer to the environmental formation tank 12 than to the water storage tank 31. For this reason, the configuration in which the opening degree of the electric valve 38 is adjusted can change the flow rate of steam introduced into the environmental formation tank 12 more quickly than the configuration in which the amount of steam generated in the water storage tank 31 is adjusted. Moreover, in the configuration in which the amount of steam generated is adjusted by adjusting the output of the heater 32 of the water storage tank 31, there is a possibility of a response delay due to the influence of the water volume stored in the water storage tank 31. However, in the configuration in which the flow rate of steam introduced into the environmental formation tank 12 is adjusted by adjusting the opening degree of the electric valve 38, such a response delay does not occur, and the responsiveness is good. Furthermore, in a configuration where the amount of steam generated is adjusted by adjusting the output of the heater 32 of the water storage tank 31, the heat output of the heater 32 and the amount of steam generated are not necessarily in a linear relationship, making it difficult to control the timing of generating a predetermined amount of steam. However, in a configuration where the flow rate of steam introduced into the environmental formation tank 12 is adjusted by adjusting the opening degree of the electric valve 38, the flow rate of steam can be controlled according to the opening degree of the electric valve 38. Therefore, it is easier to control the timing of introducing steam into the environmental formation tank 12. Consequently, it is possible to adjust the flow rate of steam introduced into the environmental formation tank 12 while suppressing response delays.

[0049] Furthermore, in this embodiment, water vapor is generated in the water storage tank 31 before starting humidity operation. However, although the water vapor generated by the steam generator 14 flows into the piping 16, it does not pass through the electric valve 38, and therefore the generated water vapor does not flow into the environment formation tank 12. Then, when starting humidity operation, the water vapor is introduced into the environment formation tank 12. At this time, the water vapor is already present up to the electric valve 38, so the electric valve 38 can be controlled to introduce the water vapor into the environment formation tank 12 at the right time. Therefore, even when starting humidity operation, the response delay of humidity control can be suppressed.

[0050] Furthermore, in this embodiment, the opening degree of the electric valve 38 is gradually increased when humidity operation starts. Therefore, it is possible to prevent a sudden change in the amount of water vapor generated due to a sudden change in the pressure inside the water storage tank 31 as the opening degree of the electric valve 38 is increased. For example, if the opening degree of the electric valve 38 is rapidly increased so that water vapor flows into the environment formation tank 12, there is a risk that the water stored in the water storage tank 31 will boil over. However, by gradually increasing the opening degree of the electric valve 38, boiling over can be prevented. Thus, it is possible to prevent a sudden increase in the amount of water vapor generated.

[0051] Furthermore, in this embodiment, the heater 32 is controlled so that the water temperature in the water storage tank 31 remains constant during humidity operation, thereby stabilizing the amount of water vapor generated during humidity operation. As a result, the relationship between the opening degree of the electric valve 38 and the amount of water vapor flowing into the environmental formation tank 12 can be stabilized. Consequently, humidity control during humidity operation can be performed more accurately.

[0052] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The present invention is not limited to the embodiments described above, and various modifications and improvements are possible without departing from its spirit. For example, in humidity operation, the heater control unit 45c is configured to adjust the output of the heater 32 so that the water temperature measured by the water thermometer 34 reaches a predetermined temperature, but it is not limited to this. For example, the heater control unit 45c may be configured to adjust the output of the heater 32 so that the detected pressure becomes a set pressure based on the detection result from the pressure sensor 41. In this case, the heater output is PID controlled so that the detected pressure becomes the set pressure. In this case, since the pressure changes sensitively depending on the opening degree of the electric valve 38, a moving average over a certain period of time may be used as the detected pressure.

[0053] In humidity operation, the amount of water vapor required differs between high-humidity operation (high set humidity) and low-humidity operation (low set humidity). Therefore, the opening degree of the electric valve 38 tends to be larger in high-humidity operation. Consequently, the pressure detected by the pressure sensor 41 may be lower in high-humidity operation. To address this, by controlling the heater 32 so that the pressure in the water tank 31 remains constant regardless of the set humidity, the heater output is controlled to a higher level during high-humidity operation when the detected pressure tends to be lower. This allows for the generation of more water vapor during high-humidity operation, enabling control that matches the required amount of water vapor.

[0054] Furthermore, the set pressure in the water storage tank 31 may be varied depending on the set humidity. For example, the set pressure during high humidity operation may be set to a higher value than the set pressure during low humidity operation. That is, since the amount of water vapor required is less during low humidity operation, the amount of water vapor generated may be kept low by keeping the set pressure low. In this case, the set pressure may be added to or subtracted according to the set humidity.

[0055] Furthermore, even when the heater control unit 45c controls the output of the heater 32 based on the detection result from the pressure sensor 41, a limit may be placed on the rate of change of the electric valve 38 when humidity operation starts.

[0056] In the above embodiment, the control is configured to maintain the set humidity at a constant value during humidity operation. However, instead, the humidity operation may be performed in a way that gradually changes the set humidity. For example, the set humidity may be changed linearly. When the set humidity is changed linearly, the opening degree of the electric valve 38 will be changed in accordance with the change in the set humidity. That is, the opening degree of the electric valve 38 is adjusted based on the difference between the acquired humidity and the set humidity. For example, if the set humidity gradually increases, the opening degree of the electric valve 38 may gradually increase. In this case, the actual humidity also changes linearly, and as a result, the humidity inside the environmental test chamber 18 is adjusted in accordance with the change in the set humidity. Moreover, the method of adjusting the opening degree of the electric valve 38 has good responsiveness, resulting in good humidity control.

[0057] In the above embodiment, humidity operation is performed after temperature operation, but temperature operation may be omitted. In this case, a preparatory operation to generate water vapor may be performed before starting humidity operation. In this preparatory operation, the heater control unit 45c operates the heater 32 of the steam generator 14 to generate water vapor. At this time, the electric valve 38 is closed. Then, after the temperature of the water thermometer 34 reaches the set temperature, or after the pressure of the pressure sensor 41 reaches the set pressure, humidity operation is started. Note that this preparatory operation may also be omitted, and only humidity operation may be performed.

[0058] In the above embodiment, the pressure sensor 41 can be omitted in order to control the heater 32 to keep the water temperature constant during humid operation. In this case, if the opening of the electric valve 38 is gradually increased at the start of humid operation, the opening may be increased by a predetermined amount at predetermined intervals, or at an opening speed within a predetermined limit.

[0059] Furthermore, the relief valve 42 can also be omitted. For example, if the water storage tank 31 is not a sealed structure and is configured to overflow when the amount of stored water exceeds a predetermined amount, the relief valve 42 can be omitted. Alternatively, instead of opening the relief valve 42 when a predetermined pressure is reached, the heater 32 may be stopped.

[0060] The environmental formation apparatus 10 in the above embodiment is configured such that the environmental formation tank 12 is a constant temperature and humidity chamber for conducting environmental tests, but is not limited to this. For example, the environmental formation apparatus 10 may be configured as a food equipment (e.g., a maturation chamber, a steam convection oven, etc.) for exposing ingredients or food to a predetermined humidity environment. In this case, a steam generator 14 may be provided separately from the environmental formation tank 12 which has an environmental formation chamber 18 in which food is contained, and the steam generated by this steam generator 14 may be introduced into the environmental formation tank 12. [Explanation of Symbols]

[0061] 10:Environment shaping device 12:Environment formation tank 14: Steam generator 16: Piping 18:Environment formation room 28: Humidity detector 31: Water storage tank 32: Heater 38: Electric valve 42: Relief valve 45: Controller

Claims

1. An environmental formation tank having an environmental formation chamber for forming a predetermined humidity environment, A steam generator having a water tank and a heater, configured to generate steam by heating the water stored in the water tank with the heater, A pipe connecting the aforementioned environmental formation tank and the aforementioned steam generator, An electric valve provided in the aforementioned piping, A humidity detector for obtaining the humidity of the aforementioned environmental conditioning room, A controller configured to control the heater and the electric valve, Equipped with, The controller is configured to perform control in humidity operation to control the humidity in the environment formation chamber by changing the opening degree of the electric valve based on the humidity acquired by the humidity detector, and before starting the humidity operation to control the humidity in the environment formation chamber, it controls the heater to generate water vapor in the water tank and controls the electric valve so that the generated water vapor does not flow into the environment formation tank or hardly flows in at all, and when the humidity operation starts, it controls the electric valve so that the generated water vapor flows into the environment formation tank.

2. An environmental formation tank having an environmental formation chamber for forming a predetermined humidity environment, A steam generator having a water tank and a heater, configured to generate steam by heating the water stored in the water tank with the heater, A pipe connecting the aforementioned environmental formation tank and the aforementioned steam generator, An electric valve provided in the aforementioned piping, A pressure detector for detecting the pressure in the piping or the water storage tank, A humidity detector for obtaining the humidity of the aforementioned environmental conditioning room, A controller configured to control the heater and the electric valve, Equipped with, The controller is an environmental formation device that, in humidity operation to control the humidity in the environmental formation chamber, performs control to change the opening degree of the electric valve based on the humidity acquired by the humidity detector, and controls the heater so that the pressure detected by the pressure detector becomes a predetermined pressure.

3. The environmental forming apparatus according to claim 1 or 2, wherein the controller is configured to control the electric valve to gradually increase its opening degree when the humidity operation starts, and then transition to controlling the opening degree of the electric valve based on the humidity obtained by the humidity detector.

4. The environmental conditioning apparatus according to claim 1 or 2, wherein the controller is configured to switch to controlling the opening degree of the electric valve based on the humidity acquired by the humidity detector when the humidity operation starts.

5. The environmental conditioning apparatus according to claim 1 or 2, wherein the controller controls the heater so that the water temperature in the water storage tank remains constant during the humidity operation.

6. A relief valve is provided in the piping at a point closer to the water tank than the electric valve. The environment forming apparatus according to claim 1 or 2.

7. An environmental formation method for forming a predetermined humidity environment in an environmental formation chamber within an environmental formation tank, In the steam generator located outside the aforementioned environmental formation tank, steam is generated by heating the water stored in the water storage tank with a heater. The humidity of the environment formation room is obtained using a humidity detector. An environmental formation method comprising: controlling the heater to generate water vapor in the water storage tank and controlling an electric valve provided in the piping connecting the environmental formation tank and the steam generator so that the generated water vapor does not flow into the environmental formation tank or hardly flows in at all, before starting humidity operation to control the humidity in the environmental formation chamber; controlling the electric valve to allow the generated water vapor to flow into the environmental formation tank when the humidity operation is started; and adjusting the opening degree of the electric valve based on the humidity obtained by the humidity detector during the humidity operation to adjust the humidity in the environmental formation chamber.

8. An environmental formation method for forming a predetermined humidity environment in an environmental formation chamber within an environmental formation tank, In the steam generator located outside the aforementioned environmental formation tank, steam is generated by heating the water stored in the water storage tank with a heater. The humidity of the environment formation room is obtained using a humidity detector. A pressure sensor detects the pressure in the piping connecting the environmental formation tank and the steam generator or the pressure inside the water storage tank. An environmental formation method for controlling the humidity inside the environmental formation chamber, wherein, in humidity operation for controlling the humidity inside the environmental formation chamber, the opening degree of an electric valve provided in the piping is adjusted based on the humidity obtained by the humidity detector, and the heater is controlled so that the pressure detected by the pressure detector becomes a predetermined pressure, thereby adjusting the humidity inside the environmental formation chamber.

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