Culture apparatus and humidity sensor calibration method

Abstract

This culture device is provided with: a first steam supply unit that humidifies the inside of a culture chamber; a humidity sensor for detecting the humidity in the culture chamber; and a calibration unit that sets the humidity inside the culture chamber to a known equilibrium humidity by means of the first steam supply unit, and calibrates the humidity sensor on the basis of the measured value of the humidity sensor and the equilibrium humidity.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a culture device and a calibration method of a humidity sensor. BACKGROUND

[0002] In a culture device for culturing a culture such as cells and microorganisms in a culture chamber, the inside of the culture chamber is maintained at a desired temperature (for example, 37°C) and a desired humidity (for example, 95% RH) by a heater and a steam supply device (for example, Patent Literature 1).

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Laid-Open No. 5-227942 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] The culture device measures the humidity in the culture chamber by a humidity sensor to maintain at a desired humidity. The humidity sensor changes over time, and in order to maintain its accuracy, periodic calibration (adjustment) is essential. However, in order to perform calibration, other measuring instruments that measure humidity are required, and measuring instruments that can measure high humidity with high accuracy are very expensive, and it is difficult for users to perform calibration and management on their own.

[0008] An object of the present disclosure is to provide a culture device and a calibration method of a humidity sensor that calibrates a humidity sensor without using other measuring instruments.

[0009] SOLUTION TO PROBLEM

[0010] The culture device of the present disclosure has:

[0011] a first steam supply portion that humidifies the inside of the culture chamber;

[0012] a humidity sensor that detects the humidity in the culture chamber; and

[0013] a calibration portion that calibrates the humidity sensor based on a measured value of the humidity sensor and a known equilibrium humidity of the inside of the culture chamber by the first steam supply portion.

[0014] The calibration method of the humidity sensor of the present disclosure is a calibration method of a humidity sensor that detects the humidity in a culture chamber, and includes the steps of:

[0015] humidifying the inside of the culture chamber so that the humidity in the culture chamber becomes a known equilibrium humidity;

[0016] detecting, with the humidity sensor, humidity in the culture chamber that has reached the equilibrium humidity; and

[0017] calibrating the humidity sensor based on the measured value of the humidity sensor and the equilibrium humidity.

[0018] Inventive Effects

[0019] According to the present disclosure, calibration of a humidity sensor can be performed without using other measuring instruments. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a perspective view showing an example of a culture device according to the embodiment of the present disclosure.

[0021] Figure 2 is a front view showing an outline of a culture chamber of the culture device shown in Figure 1

[0022] Figure 3 is a schematic cross-sectional view when the culture device shown in Figure 1

[0023] Figure 4 is a flowchart showing an example of a calibration method of a humidity sensor according to the embodiment of the present disclosure. DETAILED DESCRIPTION

[0024] Hereinafter, the embodiment of the present disclosure will be described in detail based on the drawings. Note that the following embodiment is merely an example, and the present disclosure is not limited to this.

[0025] Figure 1 is a perspective view showing an example of a culture device 1 according to the embodiment. Figure 2 is a front view showing an outline of a culture chamber 20 of the culture device 1 shown in Figure 1 Figure 3 is a schematic cross-sectional view when the culture device 1 shown in Figure 1

[0026] In addition, in Figures 1 to 3 , the side that the user faces when using is set as the front side (front side) of the culture device 1, and the opposite side thereof is set as the rear side (back side) of the culture device 1. In addition, the left side and the right side when the user observes the culture device 1 from the front are set as the left side and the right side of the culture device 1. In addition, the side away from the face on which the culture device 1 is disposed is set as the upper side (top side) of the culture device 1, and the opposite side thereof is set as the lower side (bottom side) of the culture device 1.

[0027] ​​​​The culture device 1 is a device that cultures a culture such as cells or microorganisms in a culture chamber 20 formed inside a substantially box-shaped casing 10. In the culture chamber 20, the temperature, humidity, O2 (oxygen) concentration, and CO2 (carbon dioxide) concentration are respectively maintained within appropriate ranges to form an atmosphere suitable for the culture of the culture. As shown in Figure 3 The casing 10 has an inner box 11, an outer box 12, an outer door leaf 13, an inner door leaf 14, and a front plate 15.

[0028] The inner box 11 is substantially box-shaped, has the culture chamber 20 on the inner side, and has an opening 21 of the culture chamber 20 on the front surface. The outer box 12 is substantially box-shaped and covers the outer side of the inner box 11 except for the opening 21. The inner box 11 and the outer box 12 are formed of metal plates. An insulating material 16 is disposed between the inner box 11 and the outer box 12. The insulating material 16 is formed of a plurality of plate-shaped insulating members that are bonded to each other by an adhesive, for example.

[0029] The outer door leaf 13 and the inner door leaf 14 open and close the opening 21. A gasket P is disposed on the outer edge of the outer door leaf 13.

[0030] The front plate 15 is disposed on the front surface of the inner box 11 and the outer box 12 and connects the inner box 11 and the outer box 12 on the periphery of the opening 21. The front plate 15 is a frame-shaped plate member having a substantially square outer periphery and connects the front end of the inner box 11 and the front end of the outer box 12 on the entire periphery of the opening 21.

[0031] The casing 10 has a heating portion 30 that heats the culture chamber 20. The heating portion 30 has a plurality of heaters that are each formed in a plate shape. Here, as an example, the heating portion 30 has heaters 31 to 34 and side heaters (not shown). These heaters 31 to 34 and side heaters are used in a normal operation mode, a dry heat sterilization operation mode, and a calibration mode described later and are controlled in such a manner that the temperature distribution inside the culture chamber 20 is uniform.

[0032] The heaters 31 to 33 and the side heaters are disposed on the outer side of the inner box 11. Specifically, the heater 31 is disposed on the top surface of the inner box 11. The heater 32 is disposed on the bottom surface of the inner box 11. The heater 33 is disposed on the back surface of the inner box 11. The side heaters are respectively disposed on the right side surface and the left side surface of the inner box 11. The heater 34 is disposed on the surface of the outer door leaf 13 on the opening 21 side.

[0033] The above-described heaters 31 to 34 and side heaters have, for example, a metal plate and a linear heater. The linear heater is disposed in such a manner that the temperature distribution of the metal plate is uniform. The linear heater itself can be constituted by one linear heater or can be constituted by a plurality of linear heaters connected in series.

[0034] Furthermore, the heating section 30 described above is only one example, and the number of heaters constituting the heating section 30, their arrangement, and the structure of the heaters themselves can be appropriately modified. For example, since the heat released from the opening 21 is greater than the heat released from other parts, additional heaters can be provided around the opening 21 to compensate for this.

[0035] In the culture chamber 20, a vertically extending pipe 22 is disposed on the rear surface of the inner side of the inner casing 11. A gas passage K is formed inside the pipe 22. A circulation blower 23 is disposed in the gas passage K. By operating the circulation blower 23, air from the culture chamber 20 is drawn in from the intake port 22a formed at the upper part of the pipe 22, and this air is blown out into the culture chamber 20 from the outlet 22b provided at the lower part of the pipe 22. Thus, forced air circulation is performed as indicated by the thick arrow. A temperature sensor 24 and gas supply devices 25a and 25b are disposed inside the pipe 22.

[0036] Temperature sensor 24 detects the temperature of culture chamber 20. Specifically, chamber temperature sensor 24 is located near suction port 22a to detect the temperature of air drawn in from suction port 22a.

[0037] Gas supply devices 25a and 25b supply adjustment gases (O2 gas, N2 (nitrogen) gas and CO2 gas) to the culture chamber 20 for adjusting the O2 gas concentration and CO2 gas concentration.

[0038] In addition, such as Figure 2 As shown, a humidity sensor 26 is disposed on the rear surface of the inner side of the culture chamber 20. The humidity sensor 26 detects the humidity of the culture chamber 20. The humidity sensor 26 is disposed on the lower part of the rear surface of the inner side of the culture chamber 20, to the left of the outlet 22b. Figure 2 The position of the humidity sensor 26 shown is an example and can be changed as appropriate.

[0039] A humidification tray D is provided between the lower part of the pipe 22 and the bottom surface of the inner box 11 to store the liquid (specifically water) to be converted into humidification steam. The water stored in the humidification tray D (hereinafter referred to as "stored water") is sterilized by irradiating ultraviolet light with a UV lamp (not shown).

[0040] The water stored in the humidifying pan D evaporates (naturally vaporizes) in approximately proportional proportion to the difference between the saturated vapor pressure corresponding to the water's temperature and the vapor pressure of the water in the gas phase within the culture chamber 20. Thus, the humidifying pan D constitutes a steam supply unit (the first steam supply unit in this disclosure) that supplies steam to the culture chamber 20 via natural vaporization. In this configuration, since steam is supplied to the culture chamber 20 via natural vaporization, the amount of steam supplied varies accordingly with the humidity of the culture chamber 20, and the humidity of the culture chamber 20 eventually reaches equilibrium at a predetermined humidity level.

[0041] The water stored in the humidifying pan D can be heated by a heater 32 located on the bottom surface of the outer side of the inner tank 11 to change the water temperature. In this case, the humidifying pan D and the heater 32 constitute a steam supply unit 60 (the first steam supply unit of this disclosure) that supplies steam to the culture chamber 20 by natural vaporization. Furthermore, the temperature of the water stored in the humidifying pan D is detected by a water temperature sensor 28, which will be described later. Here, since the heater 32 heats the water stored in the humidifying pan D to a temperature below its boiling point, it is referred to as heating. The water stored in the humidifying pan D is heated by the heater 32 and then naturally vaporizes. Similarly, in this structure, since steam is supplied to the culture chamber 20 by natural vaporization, the amount of steam supplied varies accordingly with the humidity of the culture chamber 20, and the humidity of the culture chamber 20 will eventually reach an equilibrium state at a specified humidity level.

[0042] In this embodiment, when the humidity of the culture chamber 20, which is the target value, is high, humidification is performed using a steam supply unit 60 having a humidification plate D and a heater 32. On the other hand, when the humidity of the culture chamber 20, which is the target value, is not very high, humidification can be performed using a steam supply unit having only a humidification plate D without using the heater 32 (no heating).

[0043] In addition, such as Figure 3 As shown, the back and bottom surfaces of the outer casing 12 of the housing 10 are covered by a cover 17. The space between the back of the outer casing 12 and the cover 17 forms a machine room M for arranging various devices. An electrical box 17a is installed in the machine room M. A control device 40 and the like are housed in the electrical box 17a.

[0044] In addition, the culture device 1 also includes a steam supply device 18, a dehumidification component 19, an external air temperature sensor 27, and a water temperature sensor 28. The external air temperature sensor 27 detects the temperature around the culture device 1. The water temperature sensor 28 detects the temperature of the water stored in the humidification tray D. Alternatively, the temperature of the water stored in the humidification tray D can also be estimated based on the output (e.g., the electrical current) of the heater 32 that heats the stored water; in this case, the water temperature sensor 28 may not be necessary.

[0045] The steam supply device 18 supplies steam to the incubation chamber 20. The steam supply device 18 is provided with a steam generation section 18a and a steam feed section 18b.

[0046] The steam generation section 18a is provided in the electrical box 17a and has a heater (not shown). For the steam generation section 18a, water is supplied from a tank (not shown) that stores water used for generating steam, by a pump (not shown), and the steam generation section 18a heats the water to evaporate it by the heater, thereby generating steam. The steam feed section 18b is a tube shape and supplies the steam generated by the steam generation section 18a to the incubation chamber 20.

[0047] In the steam supply device 18, the water supplied from the tank is heated by the heater to be forced to evaporate. Here, the water supplied from the tank is heated to a temperature above its boiling point to evaporate, and therefore, is called heating. The steam generation section 18a and the steam feed section 18b of the steam supply device 18 constitute a steam supply section (second steam supply section in the present disclosure) that supplies steam to the incubation chamber 20 by forced evaporation. The steam supply device 18 supplies steam to the incubation chamber 20 by forced evaporation, and therefore, the amount of steam supplied is not dependent on the humidity of the incubation chamber 20, and the desired amount of steam can be supplied.

[0048] For example, the control device 40 controls the pump to adjust the amount of water supplied to the steam generation section 18a per unit time, thereby adjusting the amount of steam supplied to the incubation chamber 20 per unit time.

[0049] The dehumidification member 19 dehumidifies the inside of the incubation chamber 20 in a manner to prevent dew condensation in the incubation chamber 20, and functions as a humidity control section. The dehumidification member 19 is made of metal and is in a rod shape. The first end portion of the dehumidification member 19 is positioned above the humidification tray D in the incubation chamber 20. The second end portion of the dehumidification member 19 is positioned in the electrical box 17a. A cooling device 19a (for example, a Peltier element) that cools the dehumidification member 19 is attached to the second end portion of the dehumidification member 19. A heat insulating material 19b is wound between the first end portion and the second end portion of the dehumidification member 19.

[0050] The control device 40 controls the cooling device 19a based on the detection values of the temperature sensor 24 in the incubation chamber 20 and the outside air temperature sensor 27, in a manner that the temperature of the first end portion of the dehumidification member 19 is lower than the indoor temperature of the incubation chamber 20. If the humidity of the incubation chamber 20 becomes relatively high, water droplets are generated only at the first end portion of the dehumidification member 19. That is, it is possible to prevent dew condensation from occurring in other parts in the incubation chamber 20 (for example, the inner surface of the inner case 11) and the culture.

[0051] It should be noted that the control of the dehumidifying member 19 can also be performed based on the detection value of the humidity sensor 26 in addition to the temperature sensor 24 and the outside air temperature sensor 27. In this case, when the detection value of the humidity sensor 26 is equal to or higher than a predetermined threshold value, the cooling device 19a is controlled so that the temperature of the first end portion of the dehumidifying member 19 becomes lower than the indoor temperature of the incubator 20. Thereby, the humidity of the incubator 20 can be increased as early as possible in the case where the detection value of the humidity sensor 26 is lower than the predetermined threshold value. The predetermined threshold value is a value lower than 100% RH, for example, 90% RH.

[0052] The water droplets generated at the first end portion of the dehumidifying member 19 fall into the humidifying tray D and are sterilized by irradiation of ultraviolet rays from the UV lamp. Therefore, even in the case where water droplets are generated, the case where the water droplets adversely affect the culture can be prevented.

[0053] The incubator 1 receives an instruction of start and stop of the incubator 1, a setting of the operation mode, and an input of various set values of the incubator 20 from the operation section 50 provided to the outer door leaf 13. The various set values of the incubator 20 are a set temperature, a set humidity, a set concentration of O2 gas, and a set concentration of CO2 gas, and the like. The control device 40 controls the circulating blower 23, the gas supply devices 25a, 25b, the heating section 30, and the like based on the input from the operation section 50. Further, the control device 40 functions as a calibration section that calibrates the humidity sensor 26 in the calibration mode described later. The operation section 50 has a display section that displays the state of the incubator 1.

[0054] The operation mode of the incubator 1 includes at least a normal operation mode (a culture operation mode), a dry heat sterilization operation mode, and a calibration mode. These operation modes are selected by the user by operating the operation section 50.

[0055] The normal operation mode is a mode in which the circulating blower 23, the gas supply devices 25a, 25b, the heating section 30, the steam supply device 18, the dehumidifying member 19, the steam supply section 60, and the like are operated in such a manner that the inside of the incubator 20 becomes a culture atmosphere, a culture humidity, and a culture temperature suitable for the culture of the culture. The culture atmosphere (the concentrations of O2, N2, and CO2 gases), the culture humidity, and the culture temperature are set by the user inputting them via the operation section 50. In the normal operation mode, water is stored in the humidifying tray D, the humidification is performed in such a manner that the inside of the incubator 20 becomes a culture humidity (for example, 95% RH), and the temperature of the inside of the incubator 20 is maintained at a culture temperature (for example, 37°C).

[0056] The dry heat sterilization operation mode is a mode in which the circulation blower 23 and the heating section 30 and the like are operated in a manner to perform dry heat sterilization in the incubation chamber 20. In the dry heat sterilization operation mode, since dry heat sterilization is to be performed, the humidifying tray D is emptied, and the temperature in the incubation chamber 20 is maintained at a sterilization temperature (for example, 180°C).

[0057] The calibration mode is a mode in which the steam supply device 18, the steam supply section 60 and the like are operated in a manner to make the incubation chamber 20 a constant humidity environment, to calibrate the humidity sensor 26. Regarding the calibration method of the humidity sensor 26 in the calibration mode, it will be described below with reference to Figure 4 the flowchart of Fig. 6.

[0058] Figure 4 is a flowchart illustrating an example of the calibration method of the humidity sensor 26 of the present embodiment.

[0059] First, the user performs an operation via the operation section 50, whereby the calibration mode is selected, and the following steps are executed. In the calibration mode, a sufficient amount of water is required in order to make the humidity in the incubation chamber 20 reach the equilibrium humidity, and therefore, for example, the humidifying tray D in which the water is to be stored or the water to be supplied to the humidifying tray D is displayed on the display section of the operation section 50 to prompt the user to set it.

[0060] (Step Sll)

[0061] The control device 40 sets the humidity in the incubation chamber 20 to the equilibrium humidity (for example, 95% RH). The equilibrium humidity is obtained in advance and is automatically set when the user selects the calibration mode. At this time, the set temperature in the incubation chamber 20 is also automatically set, and the control device 40 controls the heating section 30 in a manner to become the set temperature.

[0062] Here, the equilibrium humidity is described. When natural vaporization is performed, in the incubation chamber 20, the humidity in accordance with the temperature in the incubation chamber 20 and the temperature of the stored water of the humidifying tray D becomes an equilibrium state and is stabilized in this state. In the present embodiment, the humidity at which the equilibrium state is reached is referred to as the equilibrium humidity. Also, in the present embodiment, the equilibrium humidity in accordance with the temperature in the incubation chamber 20 and the temperature of the stored water of the humidifying tray D is obtained in advance. For example, in the manufacturing process of the incubation device 1, the above equilibrium temperature is obtained when its operation is confirmed. In the calibration mode, if the known equilibrium humidity obtained in advance is set, the control device 40 controls the heating section 30 in a manner to become the equilibrium humidity, and controls the temperature in the incubation chamber 20 and the temperature of the stored water of the humidifying tray D.

[0063] In particular, in the present embodiment, the maximum equilibrium humidity that can be achieved in the culture chamber 20 is obtained in advance and used as the equilibrium humidity. Since the equilibrium humidity depends on the temperature in the culture chamber 20 and the temperature of the stored water of the humidifying tray D, it is possible to change depending on the combination of the temperature in the culture chamber 20 and the temperature of the stored water of the humidifying tray D, but according to the inventors' knowledge, the maximum equilibrium humidity is uniquely determined depending on the structure of the culture device 1. Therefore, when the humidity sensor 26 is calibrated, the maximum equilibrium humidity can be used as the most reliable reference humidity.

[0064] In the structure of the above-described culture device 1, at least if the volume of the culture chamber 20, the surface area of the humidifying tray D, and the output (for example, the amount of electricity to be supplied) of the heater 32 disposed on the bottom surface of the inner case 11 are determined, the maximum equilibrium humidity is also uniquely determined. In this case, basically, the maximum equilibrium humidity achieved by humidification by the steam supply part 60 (the stored water of the humidifying tray D) will be uniquely determined.

[0065] Further, when the dehumidifying part 19 is operated, if the output voltage at which the dehumidifying part 19 is operated is determined, the maximum equilibrium humidity in this case will also be uniquely determined. That is, in this case, basically, the maximum equilibrium humidity achieved by humidification by the steam supply part 60 (the stored water of the humidifying tray D) and dehumidification by the dehumidifying part 19 will be uniquely determined.

[0066] Note that, although the maximum equilibrium humidity is used as the equilibrium humidity here, as described above, the equilibrium humidity is determined depending on the temperature in the culture chamber 20 and the temperature of the stored water of the humidifying tray D, and therefore, a known equilibrium humidity other than the maximum equilibrium humidity obtained in advance can also be used. Further, although it will make the calibration more time-consuming, a plurality of known equilibrium humidities including the maximum equilibrium humidity can also be used as the equilibrium humidity.

[0067] Next, a case in which the set equilibrium humidity is 95%RH as the maximum equilibrium humidity will be described.

[0068] (Step S12)

[0069] The control device 40 uses the steam supply device 18 that performs forced vaporization to humidify the culture chamber 20 to 80%RH (rapid humidification). At this time, the control device 40 refers to the humidity detected by the humidity sensor 26 to humidify the culture chamber 20 to 80%RH. 80%RH is a humidity that does not exceed the equilibrium humidity, and is a humidity that serves as a reference for switching to the steam supply part 60 that performs natural vaporization, and if the humidity sensor 26 detects 80%RH before calibration, it can be so even if the actual humidity is not 80%RH. Further, 80%RH is an example, and for example, it can be changed depending on the set equilibrium humidity.

[0070] In the present calibration mode, humidification by the steam supply device 18 is not essential. For example, if the humidity in the incubator 20 at the start of the calibration mode is high humidity (for example, 80% RH or more), the present step S12 can be skipped. On the other hand, if the humidity in the incubator 20 at the start of the calibration mode is not high humidity (for example, less than 80% RH), the present step S12 is preferably executed in order to shorten the time required for the calibration mode.

[0071] (Step S13)

[0072] The control device 40 humidifies the inside of the incubator 20 using the steam supply portion 60 that performs natural vaporization. As described above, when natural vaporization is performed, the inside of the incubator 20 becomes in equilibrium at the equilibrium humidity depending on the temperature of the incubator 20 and the temperature of the stored water of the humidification tray D, and stabilizes in this state.

[0073] (Step S14)

[0074] The control device 40 confirms whether or not 60 minutes have passed since the start of the calibration mode. If 60 minutes have passed (Yes), the process proceeds to step S15, and if 60 minutes have not passed (No), the process returns to step S13. 60 minutes is an example, and in the present embodiment, 60 minutes is the time required for the inside of the incubator 20 to reach 85% RH or more in the case where the steam supply device 18 and the steam supply portion 60 are normally operating. That is, as the time of the present step, only the time required for the inside of the incubator 20 to reach high humidity (for example, 85% RH) needs to be set, and can be changed according to the set equilibrium humidity.

[0075] (Step S15)

[0076] The control device 40 confirms whether or not the humidity in the incubator 20 has reached 85% RH or more using the humidity sensor 26. If 85% RH or more has been reached (Yes), the process proceeds to step S16, and if 85% RH or more has not been reached (No), the process proceeds to step S19. Here as well, the control device 40 confirms whether or not the humidity in the incubator 20 has reached 85% RH or more using the humidity sensor 26. 85% RH is the humidity used as a reference criterion for confirming whether or not high humidity has been reached in the incubator 20, and if the humidity sensor 26 detects 85% RH before calibration, this can be so even if the actual humidity is not 85% RH. Furthermore, 85% RH is an example, and can be changed according to the set equilibrium humidity, for example.

[0077] In the present step S15, the control device 40 monitors the humidity in the incubator 20 to confirm whether or not high humidity has been reached in the incubator 20, taking into account the following example cases, and the like.

[0078] For example, if the user forgets to add water to the humidifying tray D, the high humidity will not be achieved in the incubator 20. Therefore, the control device 40 repeatedly performs the humidification in step S13 and the humidity confirmation in this step S15 within 180 minutes prescribed in step S19 described later. Also, in a case where the high humidity is not achieved in the incubator 20 even after the 180 minutes, the control device 40 proceeds to step S20 described later and displays an error.

[0079] Further, at the time of the start of the incubator 1, the humidity in the incubator 20 can be low, in which case it takes time to achieve the high humidity in the incubator 20. Therefore, the control device 40 repeatedly performs the humidification in step S13 and the humidity confirmation in this step S15 within 180 minutes prescribed in step S19. Also, if the high humidity is achieved in the incubator 20 within the 180 minutes, the control device 40 proceeds to step S16.

[0080] Thus, in this step S15, it is confirmed whether the high humidity is achieved in the incubator 20, and in a case where the high humidity is not achieved in the incubator 20, step S18 described later is not proceeded to, so that it is possible to prevent a case where the humidity sensor 26 is erroneously calibrated.

[0081] (Step S16)

[0082] The control device 40 determines whether the temperature in the incubator 20 is constant using the temperature sensor 24. If it is determined that the temperature is constant (Yes), step S17 is proceeded to, and if it is not determined that the temperature is constant (No), step S19 is proceeded to. The control device 40 determines that the temperature is constant when the temperature detected by the temperature sensor 24 is within a range of, for example, [set temperature - 0.5°C] to the set temperature. As an example, if the set temperature is 50°C, it is determined that the temperature is constant when it is within a range of 49.5°C to 50°C.

[0083] In this step S16, the control device 40 monitors the temperature in the incubator 20 to confirm whether the temperature in the incubator 20 is constant at the set temperature, considering, for example, a case where the temperature in the incubator 20 is low at the time of the start of the incubator 1.

[0084] For example, at the time of the start of the incubator 1, the temperature in the incubator 20 is low. Therefore, the control device 40 controls the heating portion 30 so that the temperature in the incubator 20 becomes the set temperature and repeatedly performs the temperature confirmation in this step S16 within 180 minutes prescribed in step S19. Also, if the temperature in the incubator 20 becomes constant at the set temperature within the 180 minutes, the control device 40 proceeds to step S17.

[0085] Thus, in the present step S16, it is confirmed whether the temperature in the incubation chamber 20 is constant at the set temperature, and if the temperature does not reach constant at the set temperature, the step S18 is not entered, so it is possible to prevent a case where the humidity sensor 26 is calibrated erroneously. For example, if the temperature in the incubation chamber 20 is lower than the set temperature, the relative humidity increases, but in the present step S16, if the temperature in the incubation chamber 20 is lower than the set temperature, the step S18 is not entered, so the humidity sensor 26 is not calibrated erroneously.

[0086] (Step S17)

[0087] The control device 40 determines whether the humidity change rate in the incubation chamber 20 continues within a prescribed value for a prescribed time or more using the humidity sensor 26. If the humidity change rate continues within the prescribed value for the prescribed time or more (YES), the step S18 is entered, and if the humidity change rate does not continue within the prescribed value for the prescribed time or more (NO), the step S19 is entered. The control device 40 determines that the humidity change rate continues within the prescribed value for the prescribed time or more, for example, when the condition that the humidity change rate is within 0.05% RH / min continues for 30 minutes or more. Even before calibration, the measurement accuracy of the humidity sensor 26 with respect to humidity change is not affected, so in order to determine whether the humidity in the incubation chamber 20 is in an equilibrium state, it is determined whether the humidity change rate continues within the prescribed value for the prescribed time or more.

[0088] In the present step S17, the control device 40 monitors the humidity change rate in the incubation chamber 20 to confirm whether the humidity in the incubation chamber 20 becomes an equilibrium state, that is, whether the equilibrium humidity is reached. Even before calibration of the humidity sensor 26, by monitoring the humidity change rate, it is possible to confirm whether the humidity in the incubation chamber 20 reaches the equilibrium humidity, so it is possible to suppress calibration error in the step S18.

[0089] (Step S18)

[0090] The control device 40 detects the humidity in the incubation chamber 20 using the humidity sensor 26 to obtain a humidity measured value, and calculates and stores a difference between the humidity measured value and the equilibrium humidity (humidity measured value - equilibrium humidity) as an offset value. The control device 40 calibrates the humidity sensor 26 using the stored offset value, and controls the humidity in the normal operation mode, for example. Thus, the control device 40 is able to calibrate the humidity sensor 26 based on the humidity measured value of the humidity sensor 26 and the equilibrium temperature.

[0091] (Step S19)

[0092] The control device 40 confirms whether or not 180 minutes have passed since the start of the calibration mode. If 180 minutes have passed (YES), the process proceeds to step S20, and if 180 minutes have not passed (NO), the process returns to step S13. 180 minutes is an example, and in the present embodiment, 180 minutes is the time required to reach the equilibrium humidity of 95% RH in the incubator 20 in the case where the steam supply device 18 and the steam supply portion 60 are normally operating. That is, as the time of the present step, it is sufficient to set the time required to reach the equilibrium humidity (for example, 95% RH) in the incubator 20.

[0093] (Step S20)

[0094] The control device 40 displays an error on the display portion of the operation portion 50. As an example, if the high humidity is not reached in the incubator 20, the relevant error is displayed as described above.

[0095] As described above, in the present embodiment, the incubator 1 calibrates the humidity sensor 26 using the known equilibrium humidity that is obtained in advance, and thus the user can easily calibrate the humidity sensor 26 without using an expensive other measuring instrument. The user is provided with a simple calibration method of calibrating the humidity sensor 26.

[0096] Further, in the present embodiment, when the calibration of the humidity sensor 26 is performed using the maximum equilibrium humidity described above as the equilibrium humidity, since the maximum equilibrium humidity is uniquely determined as described above, the calibration error can be more effectively suppressed.

[0097] Further, in the present embodiment, if the operating conditions (for example, temperature, humidity, and the like) in the normal operation mode are substantially the same as the operating conditions (for example, temperature, humidity, and the like) in the calibration mode, the calibration of the humidity sensor 26 can also be performed in a state where the incubation is continuously performed (the equipment provided in the library is kept unchanged).

[0098] Further, in the present embodiment, when the calibration mode is shifted from the normal operation mode, if the operating conditions (for example, temperature, humidity, and the like) in the normal operation mode are close to the operating conditions (for example, temperature, humidity, and the like) in the calibration mode, the time to adjust the humidity in the incubator 20 to the equilibrium humidity can also be shortened. As a result thereof, the time to calibrate the humidity sensor 26 is also shortened.

[0099] Further, in the present embodiment, the incubator 1 has the dehumidifying member 19, and thus the calibration of the humidity sensor 26 can also be performed while preventing the condensation in the incubator 20 using the dehumidifying member 19.

[0100] Further, in the present embodiment, the humidity sensor 26 has a temperature detection portion that detects the temperature around the sensor and a humidity detection portion that detects the humidity around the sensor. The amount of water vapor in the incubator 20 can be calculated from the temperature and humidity around the sensor, and the humidity in the incubator 20 can be detected from the temperature of the incubator 20. Thus, the humidity in the incubator 20 can be accurately detected regardless of the temperature distribution in the incubator 20, i.e., regardless of the position of the humidity sensor 26.

[0101] The above describes the embodiments of the present disclosure. Further, the above description is an example of the preferred embodiments of the present disclosure, and the scope of the present disclosure is not limited thereto. That is, the description of the structure of the above-described device and the shape of each portion is an example, and it is obvious that various modifications and additions can be made to these examples within the scope of the present disclosure.

[0102] The disclosure of the specification, drawings, and abstract of Japanese Patent Application No. 2023-085709 filed on May 24, 2023 is incorporated herein in its entirety.

[0103] Industrial applicability

[0104] The present disclosure is useful for an incubation device and a calibration method for a humidity sensor.

[0105] Explanation of reference numerals

[0106] 1 Incubation device

[0107] 10 Housing

[0108] 11 Inner box

[0109] 12 Outer box

[0110] 13 Outer door leaf

[0111] 14 Inner door leaf

[0112] 15 Front plate

[0113] 16 Thermal insulation material

[0114] 17 Cover

[0115] 18 Steam supply device

[0116] 19 Dehumidification member

[0117] 20 Incubator

[0118] 21 Opening

[0119] 22 Duct

[0120] 23 Circulation blower

[0121] 24 temperature sensor

[0122] 25a, 25b gas supply device

[0123] 26 humidity sensor

[0124] 27 outside air temperature sensor

[0125] 28 water temperature sensor

[0126] 30 heating section

[0127] 31, 32, 33, 34 heater

[0128] 40 control device

[0129] 50 operation section

[0130] 60 steam supply section

Claims

1. A culture device, characterized by, Possessing: a first steam supply portion that humidifies the inside of a culture chamber; a humidity sensor that detects the humidity inside the culture chamber; and a calibration portion that makes the humidity inside the culture chamber a known equilibrium humidity by the first steam supply portion, and calibrates the humidity sensor based on a measured value of the humidity sensor and the equilibrium humidity.

2. The culture device according to claim 1, wherein the first steam supply portion supplies steam to the inside of the culture chamber by natural vaporization.

3. The culture device according to claim 1, wherein the calibration portion calculates a difference between the measured value and the equilibrium humidity as an offset value, and calibrates the humidity sensor.

4. The culture device according to claim 1, wherein the calibration portion determines that the humidity inside the culture chamber is the equilibrium humidity when a rate of change of the measured value continues to be within a prescribed value for a prescribed time or more.

5. The culture device according to claim 4, wherein a temperature sensor that detects the temperature inside the culture chamber is possessed, the calibration portion determines whether the humidity inside the culture chamber is the equilibrium humidity when the temperature inside the culture chamber is constant.

6. The culture device according to claim 2, wherein a second steam supply portion that supplies steam to the inside of the culture chamber by forced vaporization is possessed, the calibration portion supplies steam supplied by the second steam supply portion until a humidity that does not exceed the equilibrium humidity is reached.

7. The culture device according to claim 2, wherein a humidity control portion that prevents dew formation inside the culture chamber is possessed, the calibration portion makes the humidity inside the culture chamber the equilibrium humidity by the first steam supply portion and the humidity control portion.

8. The culture device according to claim 1, wherein the equilibrium humidity is the maximum equilibrium humidity that can be reached inside the culture chamber.

9. A method of calibrating a humidity sensor, which is a method of calibrating a humidity sensor that detects humidity in a culture chamber, characterized by, including the steps of: humidifying the inside of the culture chamber so that the humidity inside the culture chamber becomes a known equilibrium humidity; detecting the humidity inside the culture chamber that has become the equilibrium humidity with the humidity sensor; and calibrating the humidity sensor based on a measured value of the humidity sensor and the equilibrium humidity.

9. The culture device according to claim 1, wherein the equilibrium humidity is the maximum equilibrium humidity that can be reached inside the culture chamber. including the steps of: humidifying the inside of the culture chamber so that the humidity inside the culture chamber becomes a known equilibrium humidity; detecting the humidity inside the culture chamber that has become the equilibrium humidity with the humidity sensor; and calibrating the humidity sensor based on a measured value of the humidity sensor and the equilibrium humidity.

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