Culture device and control method

Abstract

This culture device comprises: an evaporator that generates steam and supplies the steam to a culture chamber; a heater that heats the evaporator; and a control unit that controls the heater. The control unit changes the magnitude of the drive voltage of the heater in accordance with the temperature of the heater to raise the temperature of the heater to a target temperature.

Description

Culture apparatus and control method

[0001] This disclosure relates to a culture apparatus and a control method.

[0002] Conventional culture apparatuses for culturing cells, microorganisms, and other culture targets have been known (see Patent Document 1). This culture apparatus is equipped with a humidifying means for adjusting the humidity of the culture chamber to a state suitable for culture. The humidifying means adjusts the humidity of the culture chamber by evaporating water from an evaporation dish placed inside the culture chamber.

[0003] Japanese Patent Publication No. 2017-201886

[0004] In the technical field related to the culture apparatus described above, there is a need for a culture apparatus and control method that can humidify the culture chamber in a short amount of time.

[0005] This disclosure is made in view of these circumstances and aims to provide a culture apparatus and control method that can humidify a culture chamber in a short time.

[0006] One embodiment of the culture apparatus according to this disclosure comprises an evaporator that generates steam and supplies steam to a culture chamber, a heater that heats the evaporator, and a control unit that controls the heater, wherein the control unit switches the magnitude of the drive voltage of the heater according to the temperature of the heater to raise the temperature of the heater to a target temperature.

[0007] One embodiment of the control method relating to this disclosure is a control method implemented in a culture apparatus comprising an evaporator that generates steam and supplies steam to a culture chamber, and a heater that heats the evaporator, and includes the steps of: obtaining the temperature of the heater; and switching the magnitude of the heater's drive voltage according to the temperature to raise the heater's temperature to a target temperature.

[0008] According to this disclosure, a culture apparatus and control method can be provided that can humidify a culture chamber in a short time.

[0009] Figure 1 is a perspective view of a culture apparatus according to an embodiment of the present disclosure. Figure 2 is a cross-sectional view of the culture apparatus. Figure 3 is a cross-sectional view of a humidifier. Figure 4 is a circuit diagram showing a humidifier control circuit. Figure 5 is a flowchart showing the processing of a first example of humidifier control. Figure 6 is a timing chart showing the operation of the humidifier control circuit in a first example of humidifier control. Figure 7 is a timing chart showing the operation of the humidifier control circuit in a second example of humidifier control.

[0010] The culture apparatus according to this disclosure will be described below with reference to the drawings. The same reference numerals will be used for the same components. The information described below, along with the attached drawings, is for illustrative purposes only and does not represent the only possible embodiment.

[0011] [Embodiment] A culture apparatus 1 according to an embodiment of this disclosure will be described with reference to Figures 1 to 7.

[0012] Figure 1 is a perspective view of the culture apparatus 1. Figure 2 is a cross-sectional view of the culture apparatus 1. Specifically, Figure 2 is a cross-sectional view showing the central part of the culture apparatus 1 in the left-right direction, cut by planes parallel to the front-back and up-down directions.

[0013] In describing the structure of the culture apparatus 1 below, the Cartesian coordinate system (X, Y, Z) shown in each figure may be used. The X direction corresponds to the front-to-back direction of the culture apparatus 1. The X-direction + side is the front side of the culture apparatus 1. The X-direction - side is the rear side of the culture apparatus 1.

[0014] Furthermore, the Y direction refers to the left-right and width directions of the culture device 1. The Y-direction + side is the left side when viewing the culture device 1 from the front. The Y-direction - side is the right side when viewing the culture device 1 from the front.

[0015] The Z direction is the vertical and height direction of the culture device 1. The Z+ side is the upper side of the culture device 1. The Z- side is the lower side of the culture device 1. Note that the directions of the culture device 1 are not limited to the Cartesian coordinate system (X, Y, Z) shown in each figure.

[0016] Culture apparatus 1 is a device for culturing target organisms such as cells and microorganisms. Culture apparatus 1 has a box body 101, an inner door 102, and an outer door 103. Note that the inner door 102 is omitted in Figure 1.

[0017] The box body 101 is box-shaped and has a culture chamber 101d inside. Specifically, as shown in Figure 2, the box body 101 has an inner box 101a, an outer box 101b, and an insulating material 101c.

[0018] The inner box 101a is made of metal plates and is box-shaped with an open front. The space enclosed by the inner box 101a constitutes the culture chamber 101d.

[0019] The outer box 101b is made of a metal plate and is box-shaped with an open front. The outer box 101b is positioned to cover the outer surface of the inner box. The insulating material 101c is provided between the inner box 101a and the outer box 101b.

[0020] The culture chamber 101d has an opening 101e at its front. The culture chamber 101d is partitioned vertically by a plurality of shelves 101f.

[0021] The inner door 102 is supported at the front end of the inner box 101a in a manner that allows the opening 101e to be opened and closed. The outer door 103 is also supported at the front end of the outer box 101b in a manner that allows the opening 101e to be opened and closed.

[0022] The culture apparatus 1 has a packing 104 on the outer peripheral edge of the inner surface of the outer door 103. The culture apparatus 1 also has a cover 105 on the back and bottom of the outer box 101b.

[0023] Furthermore, the culture apparatus 1 has a machine room 106 for arranging various equipment between the back of the outer casing 101b and the cover 105. The culture apparatus 1 also has an electrical box 107 in the machine room 106. In addition, the culture apparatus 1 has a control device 3 and other electrical components (not shown) in the electrical box 107.

[0024] Furthermore, the culture apparatus 1 has a duct 108 that extends vertically into the culture chamber 101d. The duct 108 is detachably attached to the back of the inner box 101a. A gas passage 109 is formed inside the duct 108.

[0025] Furthermore, the culture apparatus 1 has a blower 110 in the gas passage 109. The blower 110 draws air into the gas passage 109 from an intake port 108a formed at the top of the duct 108. This air passes through the gas passage 109 and is blown out into the culture chamber 101d from an outlet port 108b provided at the bottom of the duct 108. As a result, the air is forcibly circulated within the culture chamber 101d.

[0026] The culture apparatus 1 has a gas supply device 111 in the duct 108. The gas supply device 111 is O from the culture chamber 101d ２ Gas concentration, N ２ concentration, and CO ２ Adjusting gas (O) for adjusting gas concentration ２ Gas, N ２ Gas, and CO ２ The gas is supplied to the culture room 101d.

[0027] Furthermore, the culture apparatus 1 has an environmental sensor (not shown) in the duct 108 that measures the temperature, humidity, and gas concentration of the culture chamber 101d. The culture apparatus 1 also has an ultraviolet irradiation device (not shown) in the duct 108 that sterilizes the air in the culture chamber 101d by irradiating it with ultraviolet light.

[0028] Furthermore, the culture apparatus 1 has culture chamber heaters 112 on the back surfaces (outer box side) of the right, left, rear, top, and bottom walls of the inner box 101a for adjusting the temperature of the culture chamber 101d.

[0029] Figure 1 shows only the culture chamber heater 112 installed on the rear wall. The culture chamber heater 112 is basically energized and generating heat while the culture apparatus 1 is operating. The operation of the culture chamber heater 112 is controlled by the control device 3.

[0030] Furthermore, the culture apparatus 1 has a humidifier 113. The humidifier 113 is installed in a through hole 101g provided on the rear side of the box body 101. The through hole 101g penetrates the inner box 101a, the outer box 101b, and the insulating material 101c in the front-to-back direction.

[0031] The humidifier 113 supplies steam to the culture chamber 101d, thereby humidifying the culture chamber 101d. In this embodiment, the culture apparatus 1 is equipped with an evaporative humidifier that adjusts the humidity of the culture chamber by evaporating the water in an evaporation dish placed inside the culture chamber, along with the humidifier 113. However, the culture apparatus 1 does not necessarily have to be equipped with an evaporative humidifier.

[0032] Furthermore, the culture apparatus 1 has an operating device 114 on the front of the outer door 103. The operating device 114 receives input from the user for instructions to start and stop the culture apparatus 1, to set the operating mode, and to input various setting values ​​for the culture chamber 101d.

[0033] The various settings for culture room 101d are: set temperature, set humidity, O ２ The set concentration of the gas, and CO ２ This includes the set concentration of the gas.

[0034] The control device 3 controls the blower 110, gas supply device 111, culture room heater 112, and humidifier 113, etc., based on input from the operating device 114 and environmental sensors (not shown). The operating device 114 has a display unit (not shown) that displays the status of the culture apparatus 1.

[0035] The culture apparatus 1 according to this embodiment, having the basic configuration described above, controls the operation of the humidifier 113 in order to humidify the culture chamber 101d in a short time. The specific configuration of the humidifier 113 will be described below. After that, the specific control of the humidifier 113 will be described.

[0036] As shown in Figures 2 and 3, the humidifier 113 includes a tank 113a, a pump 113b, an evaporator 113c, a discharge pipe 113d, a nozzle member 113e, a heater 113f, and a temperature sensor 113g.

[0037] Tank 113a is a container for storing water. Tank 113a is located in the machine room 106. However, the location of tank 113a is not limited to the machine room 106.

[0038] Pump 113b is connected to tank 113a via piping. Pump 113b is located in the machine room 106. However, the location of pump 113b is not limited to the machine room 106.

[0039] Pump 113b supplies water from tank 113a to evaporator 113c. Pump 113b is a pump (for example, a tube pump) that can deliver small amounts of water from within pump 113b.

[0040] The evaporator 113c is connected to the pump 113b via piping. The evaporator 113c is located inside the through-hole 101g provided in the housing 101. The evaporator 113c has an evaporation space 113h inside.

[0041] The evaporation space 113h is heated by a heater 113f. The heater 113f is located around (below in this embodiment) the evaporation space 113h in the evaporator 113c.

[0042] The temperature sensor 113g is located around the heater 113f in the evaporator 113c. The temperature sensor 113g detects information regarding the temperature of the heater 113f. The temperature sensor 113g sends the detected information regarding the temperature of the heater 113f to the control device 3.

[0043] The discharge pipe 113d is a hollow axial member. The base end of the discharge pipe 113d is connected to the evaporator 113c. The opening at the base end of the discharge pipe 113d communicates with the evaporation space 113h.

[0044] Furthermore, the opening at the tip of the discharge pipe 113d is in communication with the culture chamber 101d. The nozzle member 113e supports the tip of the discharge pipe 113d on the rear side surface of the inner box 101a.

[0045] The humidifier 113, having the configuration described above, supplies steam to the culture chamber 101d under the control of the control device 3.

[0046] Specifically, water in tank 113a is supplied to evaporation space 113h by pump 113b. Evaporation space 113h is heated by heater 113f. Therefore, the water evaporates into steam within evaporation space 113h.

[0047] The steam generated in the evaporation space 113h is supplied to the culture chamber 101d through the discharge pipe 113d.

[0048] The control device 3 is an example of a control unit and comprehensively controls the operation of the humidifier 113 described above. This type of control is called humidification control. In this embodiment, the culture apparatus 1 has a humidification control circuit 4 in order to perform humidification control. Figure 4 is a circuit diagram showing the humidification control circuit 4.

[0049] The humidification control circuit 4 includes a control device 3, a power supply 41, a high-voltage converter 42, a low-voltage converter 43, a heater 113f, and a switch circuit 44.

[0050] As described above, the control device 3 is located inside the electrical box 107 provided in the culture apparatus 1. The control device 3 controls the state of the humidification control circuit 4 using control signals.

[0051] The power supply 41 supplies voltage (in other words, power) to the heater 113f. In this embodiment, the power supply 41 supplies a predetermined AC voltage.

[0052] The high-voltage converter 42 is connected to the power supply 41. The high-voltage converter 42 converts the AC voltage supplied from the power supply 41 into a DC high-level drive voltage. The high-voltage converter 42 then supplies the high-level drive voltage. The high-level drive voltage is sometimes also called the first DC voltage.

[0053] In this embodiment, the high-level drive voltage is 24V. The high-level drive voltage may be appropriately determined according to the characteristics of the heater 113f.

[0054] The high-voltage converter 42 constitutes a high-level power supply unit that supplies a high-level drive voltage to the heater 113f.

[0055] Such a high-voltage converter 42 is connected to the heater 113f via the high-voltage side line L1. The high-level drive voltage supplied by the high-voltage converter 42 is supplied to the heater 113f via the high-voltage side line L1.

[0056] Furthermore, the high-voltage converter 42 is connected to the heater 113f via the low-voltage converter 43 (described later) and the low-voltage side line L2. The low-voltage side line L2 connects the low-voltage converter 43 (described later) and the heater 113f and is wired in parallel with the high-voltage side line L1.

[0057] The high-level drive voltage supplied by the high-voltage converter 42 is converted to a DC low-level drive voltage by the low-voltage converter 43 and supplied to the heater 113f via the low-voltage side line L2. The low-level drive voltage is sometimes referred to as the second DC voltage.

[0058] The low-voltage converter 43 is connected to the high-voltage converter 42. The low-voltage converter 43 is located downstream of the high-voltage converter 42 (in other words, on the heater 113f side).

[0059] The low-voltage converter 43 converts the high-level drive voltage supplied from the high-voltage converter 42 into a low-level drive voltage. The low-voltage converter 43 then supplies the low-level drive voltage.

[0060] In this embodiment, the low-level drive voltage is 12V. The low-level drive voltage may be any voltage lower than the high-level drive voltage. The low-level drive voltage may be appropriately determined according to the characteristics of the heater 113f.

[0061] The low-voltage converter 43 constitutes a low-level power supply unit that supplies a low-level drive voltage to the heater 113f. The low-voltage converter may be connected to the power supply 41 instead of the high-voltage converter 42. In this case, the low-voltage converter may convert the AC voltage supplied from the power supply 41 into a DC low-level drive voltage (in other words, a second DC voltage).

[0062] As described above, the heater 113f is provided around the evaporation space 113h in the humidifier 113. The heater 113f is connected to the power supply 41 and the control device 3 via the switch circuit 44.

[0063] Heater 113f is a heater with a positive temperature coefficient of resistance, where the resistance increases as the temperature rises. Therefore, when heater 113f reaches a predetermined temperature, the increase in resistance makes it difficult for current to flow, thus suppressing further temperature increases.

[0064] Such a heater 113f is easy to control and highly safe because, when heated above the set temperature, its resistance increases and heat generation is suppressed.

[0065] The switch circuit 44 is a circuit for switching the voltage supplied to the heater 113f. The switch circuit 44 connects the power supply 41, the control device 3, and the heater 113f.

[0066] Specifically, the switch circuit 44 includes a high-voltage side switch circuit 440, a low-voltage side control switch circuit 441, a low-voltage side drive switch circuit 442, and a delay circuit 443.

[0067] The switch circuit 44 switches between the first circuit state and the second circuit state by changing the states of the high-voltage side switch circuit 440, the low-voltage side control switch circuit 441, and the low-voltage side drive switch circuit 442 under the control of the control device 3.

[0068] In the first circuit state of the switch circuit 44, the heater 113f is connected to the high-voltage converter 42 and disconnected from the low-voltage converter 43. That is, in the first circuit state, a high-level drive voltage is supplied to the heater 113f from the high-voltage converter 42.

[0069] In the second circuit state of the switch circuit 44, the heater 113f is disconnected from the high-voltage converter 42 and connected to the low-voltage converter 43. That is, in the second circuit state, a low-level drive voltage is supplied to the heater 113f from the low-voltage converter 43.

[0070] The configuration and operation of the switch circuit 44 in this embodiment will be described below. The configuration and operation of the switch circuit 44 are not particularly limited, as long as it is possible to switch between the first circuit state and the second circuit state.

[0071] The high-voltage side switch circuit 440 is connected to the high-voltage converter 42. Specifically, the high-voltage side switch circuit 440 is located downstream of the high-voltage converter 42 (in other words, on the heater 113f side) in the high-voltage side line L1.

[0072] Furthermore, the high-voltage side switch circuit 440 is connected to the control device 3 via the high-voltage side control line CL1 and the high-voltage side drive line DL1.

[0073] The high-voltage side switch circuit 440 switches between an ON state and an OFF state based on a switch circuit control signal (see Figure 6) input from the control device 3 via the high-voltage side control line CL1 and a switch circuit drive signal (see Figure 6) input from the control device 3 via the high-voltage side drive line DL1.

[0074] The high-voltage side switch circuit 440 conducts when it is ON. When the high-voltage side switch circuit 440 is ON, the high-voltage converter 42 and the heater 113f are connected.

[0075] On the other hand, the high-voltage side switch circuit 440 is in a non-conductive state when it is OFF. When the high-voltage side switch circuit 440 is OFF, the high-voltage converter 42 and the heater 113f are disconnected.

[0076] The low-voltage side control switch circuit 441 is connected to the low-voltage converter 43. Specifically, the low-voltage side control switch circuit 441 is located downstream of the low-voltage converter 43 (in other words, on the heater 113f side) in the low-voltage side line L2.

[0077] Furthermore, the low-voltage side control switch circuit 441 is connected to the control device 3 via the low-voltage side control line CL2.

[0078] The low-voltage side control switch circuit 441 switches between an ON state and an OFF state based on a switch circuit control signal (see Figure 6) input from the control device 3 via the low-voltage side control line CL2.

[0079] In this embodiment, the switch circuit control signal flowing through the low-voltage side control line CL2 is the same signal as the switch circuit control signal flowing through the high-voltage side control line CL1.

[0080] The low-voltage side control switch circuit 441 is conductive when it is in the ON state. On the other hand, the low-voltage side control switch circuit 441 is non-conductive when it is in the OFF state.

[0081] The low-voltage drive switch circuit 442 is connected to the low-voltage control switch circuit 441. Specifically, the low-voltage drive switch circuit 442 is located downstream of the low-voltage control switch circuit 441 on the low-voltage line L2 (in other words, on the heater 113f side).

[0082] Furthermore, the low-voltage drive switch circuit 442 is connected to the control device 3 via the low-voltage drive line DL2.

[0083] The low-voltage drive switch circuit 442 switches between an ON state and an OFF state based on a switch circuit drive signal (see Figure 6) input from the control device 3 via the low-voltage drive line DL2.

[0084] In this embodiment, the switch circuit drive signal flowing through the low-voltage drive line DL2 is the same signal as the switch circuit drive signal flowing through the high-voltage drive line DL1.

[0085] The low-voltage drive switch circuit 442 is conductive when it is in the ON state. On the other hand, the low-voltage drive switch circuit 442 is non-conductive when it is in the OFF state.

[0086] When the low-voltage control switch circuit 441 is ON and the low-voltage drive switch circuit 442 is ON, the low-voltage converter 43 and the heater 113f are connected.

[0087] On the other hand, if either the low-voltage side control switch circuit 441 or the low-voltage side drive switch circuit 442 is in the OFF state, the low-voltage converter 43 and the heater 113f are disconnected.

[0088] The delay circuit 443 is provided on the high-voltage side drive line DL1 that connects the control device 3 and the high-voltage side switch circuit 440. The delay circuit 443 delays the switch circuit drive signal (see FIG. 6) input from the control device 3 by a first predetermined time D １ (hereinafter referred to as "delay time D １ ") and sends the signal to the high-voltage side switch circuit 440.

[0089] Such a delay circuit 443 is provided to prevent the heater 113f from being simultaneously connected to both the high-voltage converter 42 and the low-voltage converter 43.

[0090] Next, the operation of the humidification control circuit 4 (that is, the humidification control method) will be described. First, an outline of humidification control will be described.

[0091] The main body of the humidification control is the control device 3. In the humidification control, the control device 3 switches the magnitude of the drive voltage for the heater 113f according to the temperature of the heater 113f to raise the temperature of the heater 113f to a target temperature.

[0092] Then, the culture chamber 101d is humidified by the steam supplied from the humidifier 113. After raising the humidity of the culture chamber 101d to a set humidity, the control device 3 maintains the humidity of the culture chamber 101d at the set humidity. Such humidification control can humidify the culture chamber 101d in a shorter time compared to a humidifier that evaporates water in an evaporation dish arranged in the culture chamber.

[0093] The temperature of the heater 113f is acquired based on information related to the temperature of the heater 113f detected by the temperature sensor 113g. That is, the control device 3 switches the magnitude of the drive voltage for the heater 113f based on the information related to the temperature of the heater 113f acquired from the temperature sensor 113g.

[0094] The target temperature of the heater 113f is a preset temperature. In the present embodiment, this target temperature is 140°C. Note that the target temperature may be appropriately determined according to the characteristics of the heater and the usage environment.

[0095] Specifically, the control device 3 drives the heater 113f with a low-level drive voltage when the temperature of the heater 113f is below a first threshold.

[0096] In other words, when the temperature of the heater 113f is below a first threshold, the control device 3 turns on the low-voltage side control switch circuit 441 and the low-voltage side drive switch circuit 442, connecting the heater 113f to the low-voltage converter 43.

[0097] In this state, the control device 3 turns off the high-voltage side switch circuit 440, disconnecting the heater 113f from the high-voltage converter 42. The first threshold temperature is, for example, 110°C. The first threshold temperature may be determined appropriately depending on the characteristics of the heater and the operating environment.

[0098] On the other hand, if the temperature of the heater 113f is greater than the first threshold, the control device 3 drives the heater 113f with a high-level drive voltage.

[0099] In other words, when the temperature of the heater 113f is greater than the first threshold, the control device 3 turns on the high-voltage side switch circuit 440 and connects the heater 113f to the high-voltage converter 42.

[0100] In this state, the control device 3 turns off the low-voltage side control switch circuit 441 and disconnects the heater 113f from the low-voltage converter 43.

[0101] Specifically, the control device 3 disconnects the heater 113f from the low-voltage converter 43 if the temperature of the heater 113f is greater than a first threshold. Then, after a first predetermined time has elapsed, the control device 3 connects the heater 113f to the high-voltage converter 42. The first predetermined time is the time D that is delayed by the delay circuit 443 after the control device 3 sends a switch circuit drive signal to the high-voltage side switch circuit 440. １ That is the case.

[0102] Furthermore, the control device 3 stops the heater 113f when the temperature of the heater 113f reaches the target temperature.

[0103] In other words, when the temperature of the heater 113f reaches the target temperature, the control device 3 turns off the high-voltage side switch circuit 440, the low-voltage side control switch circuit 441, and the low-voltage side drive switch circuit 442.

[0104] Furthermore, when the heater 113f is stopped, the control device 3 drives the heater 113f with a high-level drive voltage if the temperature of the heater 113f falls below the target temperature by a first predetermined temperature, thereby raising the temperature of the heater 113f to the target temperature.

[0105] In other words, when the heater 113f is stopped, the control device 3 connects the heater 113f to the high-voltage converter 42 when the temperature of the heater 113f falls below the target temperature by a first predetermined temperature.

[0106] In this state, the control device 3 turns off the low-voltage side control switch circuit 441, disconnecting the heater 113f from the low-voltage converter 43. In this embodiment, the first predetermined temperature is 1°C. The first predetermined temperature may be appropriately determined depending on the characteristics of the heater and the operating environment.

[0107] (First Example of Humidification Control) Next, a first example of humidification control will be described with reference to Figures 5 and 6. Figure 5 is a flowchart showing the processing of the first example of humidification control. Figure 6 is a timing chart showing the operation of the humidification control circuit 4 in the first example of humidification control. Unless otherwise specified, the main component of humidification control is the control device 3.

[0108] Before the control device 3 performs the first example of humidification control, the operator operates the control device 114 to input the environmental settings for the culture room 101d. The environmental settings include target temperature, target humidity, and O ２ Target gas concentration, and CO ２ The target concentration of the gas is included. The control device 3 raises the humidity of the culture chamber 101d to the target humidity level through humidification control, and then maintains the humidity of the culture chamber 101d at the target humidity level.

[0109] (Step S101) First, in step S101 of Figure 5, the control device 3 drives the heater 113f with a low-level drive voltage. At this time, the control device 3 controls the switch circuit 44 to connect the heater 113f to the low-voltage converter 43. The control device 3 also disconnects the heater 113f from the high-voltage converter 42.

[0110] The state in which step S101 is performed by the control device 3 will be explained based on the timing chart in Figure 6.

[0111] The control device 3 drives the humidifier 113 with a low-level drive voltage, at time T in Figure 6. ０ In this configuration, a high-level switch circuit control signal is sent to the high-voltage side control line CL1.

[0112] Furthermore, the control device 3 drives the humidifier 113 with a low-level drive voltage, as shown in Figure 6 at time T ０ In this configuration, a high-level switch circuit drive signal is sent to the high-voltage drive line DL1.

[0113] As a result, the high-voltage side switch circuit 440 is activated at time T in Figure 6. ０ In this state, it enters the OFF state. Thus, the high-voltage side switch circuit 440 enters the OFF state when it receives a high-level switch circuit control signal and a high-level switch circuit drive signal.

[0114] In this example, the control device 3 outputs a high-level switch circuit control signal and a high-level switch circuit drive signal simultaneously. However, the control device 3 may output the high-level switch circuit drive signal a predetermined time (for example, 10 s) later than the high-level switch circuit control signal. With this configuration, when the heater 113f is connected to the low-voltage converter 43, the heater 113f can be reliably disconnected from the high-voltage converter 42. This predetermined time may be determined as appropriate.

[0115] Furthermore, the control device 3 controls the time T in Figure 6. ０In this process, a high-level switch circuit control signal is sent to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 is turned ON.

[0116] Furthermore, the control device 3 controls the time T in Figure 6. ０ At this point, a high-level switch circuit drive signal is sent to the low-voltage drive line DL2. As a result, the low-voltage drive switch circuit 442 operates at time T in Figure 6. ０ In this state, it becomes ON.

[0117] Time T in Figure 6 as described above ０ In the state of the switch circuit 44, the heater 113f is connected to the low-voltage converter 43. Meanwhile, at time T in Figure 6 as described above, ０ In the state of the switch circuit 44, the heater 113f is disconnected from the high-voltage converter 42.

[0118] Therefore, the heater 113f is supplied with a low-level drive voltage from the low-voltage converter 43. In other words, the heater 113f is driven by a low-level drive voltage. In this example, the low-level drive voltage is 12V.

[0119] (Step S102) First, in step S102 of Figure 5, the control device 3 determines whether the temperature of the heater 113f is higher than the first threshold.

[0120] Specifically, the control device 3 determines whether the temperature of the heater 113f has exceeded a first threshold based on the temperature information of the heater 113f obtained from the temperature sensor 113g. In this example, the first threshold is 110°C (see Figure 6). The first threshold may be determined appropriately, taking into consideration the characteristics of the humidifier 113, etc.

[0121] If the temperature of heater 113f is higher than the first threshold (YES in step S102), the control device 3 proceeds to step S103. In the timing chart of Figure 6, time T １ Then, the temperature of heater 113f becomes higher than the first threshold (110°C in this example).

[0122] On the other hand, if the temperature of the heater 113f is below the first threshold ("NO" in step S102), the control device 3 repeats the control process in step S102. In other words, the control device 3 repeats the control process in step S102 at time T in the timing chart of Figure 6. ０ ~T １ The control process in step S102 is repeated until the end.

[0123] (Step S103) Next, in step S103 of Figure 5, the control device 3 drives the heater 113f with a high-level drive voltage. At this time, the control device 3 controls the switch circuit 44 to connect the heater 113f to the high-voltage converter 42. The control device 3 also disconnects the heater 113f from the low-voltage converter 43.

[0124] The state in which step S103 is performed by the control device 3 will be explained based on the timing chart in Figure 6. Figure 6, time T １ In this case, the temperature of heater 113f becomes higher than the first threshold.

[0125] The control device 3 drives the heater 113f with a high-level drive voltage, at time T in Figure 6. １ In this configuration, a low-level switch circuit control signal is sent to the high-voltage side control line CL1.

[0126] Furthermore, in order to drive the heater 113f with a high-level drive voltage, the control device 3 operates at time T in Figure 6. １ In this configuration, a high-level switch circuit drive signal is sent to the high-voltage drive line DL1.

[0127] As a result, the high-voltage side switch circuit 440 is activated at time T in Figure 6. １ +D １ In this case, it transitions from the OFF state to the ON state. Here, D １ This is the delay time caused by the delay circuit 443 (see Figure 4). In other words, the timing at which the high-voltage side switch circuit 440 transitions from the OFF state to the ON state is time T １ D １ It will be delayed by just that much.

[0128] Thus, the high-voltage side switch circuit 440 transitions to the ON state when it receives a low-level switch circuit control signal and a high-level switch circuit drive signal.

[0129] Furthermore, the control device 3 controls the time T in Figure 6. １ In this state, a low-level switch circuit control signal is sent to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 transitions from the ON state to the OFF state.

[0130] Furthermore, the control device 3 controls the time T in Figure 6. １ In this configuration, a high-level switch circuit drive signal is sent to the low-voltage drive line DL2. As a result, the low-voltage drive switch circuit 442 maintains the ON state.

[0131] Time T in Figure 6 as described above １ In the state of the switch circuit 44 shown in Figure 6, the heater 113f is disconnected from the low-voltage converter 43. １ In the state of the switch circuit 44, the heater 113f is not connected to the high-voltage converter 42.

[0132] Then, heater 113f is at time T in Figure 6. １ +D １ At this point, it is connected to the high-voltage converter 42. Thus, in this example, at time T in Figure 6, １ In this configuration, the heater 113f is prevented from being connected to both the low-voltage converter 43 and the high-voltage converter 42 simultaneously.

[0133] Also, time T in Figure 6 １ +D １ In this configuration, when the heater 113f is connected to the high-voltage converter 42, the heater 113f is driven with a high-level drive voltage.

[0134] (Step S104) Next, in step S104 of Figure 5, the control device 3 determines whether or not the temperature of the heater 113f has reached the target temperature.

[0135] Specifically, the control device 3 determines whether the temperature of the heater 113f has reached the target temperature based on the information regarding the temperature of the heater 113f obtained from the temperature sensor 113g.

[0136] In this example, the target temperature is 140°C (see Figure 6). The target temperature may be determined as appropriate, taking into consideration the characteristics of the humidifier 113, etc.

[0137] When the temperature of heater 113f reaches the target temperature (YES in step S104), the control device 3 proceeds to step S105. In the timing chart of Figure 6, time T ２ Then, the temperature of heater 113f reaches the target temperature (140°C in this example).

[0138] On the other hand, if the temperature of the heater 113f has not reached the target temperature (NO in step S104), the control device 3 repeats the control process in step S104. In other words, the control device 3 repeats the control process in step S104 at time T in the timing chart of Figure 6. １ ~T ２ The control process in step S104 is repeated until the end.

[0139] (Step S105) Next, in step S105 of Figure 5, the control device 3 stops the heater 113f. At this time, the control device 3 controls the switch circuit 44 to disconnect the heater 113f from the high-voltage converter 42 and the low-voltage converter 43.

[0140] The state in which step S105 is performed by the control device 3 will be explained based on the timing chart in Figure 6. Figure 6, time T ２ In this state, the temperature of heater 113f reaches the target temperature.

[0141] The control device 3 stops the heater 113f at time T in Figure 6. ２ In this configuration, a low-level switch circuit control signal is sent to the high-voltage side control line CL1.

[0142] Furthermore, the control device 3 stops the heater 113f at time T in Figure 6. ２ In this configuration, a low-level switch circuit drive signal is sent to the high-voltage drive line DL1.

[0143] As a result, the high-voltage side switch circuit 440 is activated at time T in Figure 6. ２ In this state, it transitions from the ON state to the OFF state.

[0144] Furthermore, the control device 3 controls the time T in Figure 6. ２ In this configuration, a low-level switch circuit control signal is sent to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 remains in the OFF state.

[0145] Furthermore, the control device 3 controls the time T in Figure 6. ２ In this configuration, a low-level switch circuit drive signal is sent to the low-voltage drive line DL2. As a result, the low-voltage drive switch circuit 442 transitions from the ON state to the OFF state.

[0146] Time T in Figure 6 as described above ２ In the state of the switch circuit 44, the heater 113f is disconnected from the high-voltage converter 42 and the low-voltage converter 43. Therefore, the heater 113f stops.

[0147] (Step S106) Next, in step S106 of Figure 5, the control device 3 determines whether the temperature of the heater 113f is lower than the target temperature by a first predetermined temperature.

[0148] Specifically, the control device 3 determines whether the temperature of the heater 113f is lower than the target temperature by a first predetermined temperature, based on the temperature information of the heater 113f obtained from the temperature sensor 113g. In this example, the first predetermined temperature is 1°C (see Figure 6). The first predetermined temperature may be determined appropriately, taking into consideration the characteristics of the humidifier 113, etc.

[0149] If the temperature of the heater 113f is lower than the target temperature by a first predetermined temperature (YES in step S106), the control device 3 proceeds to step S103.

[0150] In the timing chart of Figure 6, time T ３Then, the temperature of heater 113f reaches a temperature that is a first predetermined temperature lower than the target temperature (139°C in this example). For the sake of explanation, the vertical axis scale of the graph showing the temperature of heater 113f in Figure 6 is shown schematically.

[0151] Here, we will explain the control process after the transition from step S106 to step S103 in Figure 5.

[0152] The control device 3 drives the heater 113f with a high-level drive voltage. At this time, the control device 3 controls the switch circuit 44 to connect the heater 113f to the high-voltage converter 42. The control device 3 also disconnects the heater 113f from the low-voltage converter 43.

[0153] Specifically, the control device 3 drives the heater 113f with a high-level drive voltage, at time T in Figure 6. ３ In this configuration, a low-level switch circuit control signal is sent to the high-voltage side control line CL1.

[0154] Furthermore, in order to drive the heater 113f with a high-level drive voltage, the control device 3 operates at time T in Figure 6. ３ In this configuration, a high-level switch circuit drive signal is sent to the high-voltage drive line DL1.

[0155] As a result, the high-voltage side switch circuit 440 is activated at time T in Figure 6. ３ +D １ In this case, it transitions from the OFF state to the ON state. Here, D １ This is the delay time caused by the delay circuit 443 (see Figure 4). In other words, the timing at which the high-voltage side switch circuit 440 turns ON is time T ３ D １ It will be delayed by just that much.

[0156] Furthermore, the control device 3 controls the time T in Figure 6. ３ In this configuration, a low-level switch circuit control signal is sent to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 remains in the OFF state.

[0157] Furthermore, the control device 3 controls the time T in Figure 6. ３At this point, a high-level switch circuit drive signal is sent to the low-voltage drive line DL2. As a result, the low-voltage drive switch circuit 442 operates at time T in Figure 6. ３ In this state, it transitions from the OFF state to the ON state.

[0158] Time T in Figure 6 as described above ３ In the state of the switch circuit 44 shown in Figure 6, the heater 113f is disconnected from the low-voltage converter 43. ３ In the state of the switch circuit 44, the heater 113f is not connected to the high-voltage converter 42.

[0159] Then, heater 113f is at time T in Figure 6. ３ +D １ At this point, it is connected to the high-voltage converter 42. Thus, in this example, at time T in Figure 6, ３ In this configuration, the heater 113f is prevented from being connected to both the low-voltage converter 43 and the high-voltage converter 42 simultaneously. This prevents an abnormal voltage from being applied to the low-voltage converter 43.

[0160] Furthermore, as shown in Figure 6, time T ３ +D １ When the heater 113f is connected to the high-voltage converter 42, the heater 113f is driven with a high-level drive voltage. Subsequently, the control device 3 repeats steps S104 to S106 in Figure 5.

[0161] On the other hand, if the temperature of the heater 113f has not reached a temperature lower than the first predetermined temperature below the target temperature (NO in step S106), the control device 3 repeats the control process in step S106. In other words, the control device 3 repeats the control process in step S106 at time T in the timing chart of Figure 6. ２ ~T ３ The control process in step S106 is repeated until the end.

[0162] Subsequently, the control device 3 terminates the first example of humidification control processing at an appropriate timing.

[0163] (Operation and Effects of the First Example of Humidification Control) As described above, in this example, the control device 3 connects the heater 113f to the low-voltage converter 43 when the temperature of the heater 113f is below the first threshold. As a result, the heater 113f is driven at a low-level drive voltage. On the other hand, when the temperature of the heater 113f exceeds the first threshold, the control device 3 connects the heater 113f to the high-voltage converter 42. As a result, the heater 113f is driven at a high-level drive voltage. This configuration allows the culture chamber 101d to be humidified in a shorter time compared to an evaporation-type humidifier that evaporates water in an evaporation dish placed in the culture chamber.

[0164] Furthermore, in this example, the drive voltage of the heater 113f can be switched in stages. In addition, in this example, the heater 113f has a positive temperature coefficient of resistance, where the resistance value increases as the temperature rises. Therefore, the resistance value of the heater 113f is high when the drive voltage of the heater 113f is switched from a low-level drive voltage to a high-level drive voltage. As a result, it is possible to suppress the peak current when the drive voltage of the heater 113f is switched (hereinafter referred to as "peak current at switching"). Therefore, the high-voltage converter 42 can be miniaturized. Note that the temperature coefficient of resistance of the heater 113f may be appropriately determined according to the performance required of the humidifier 113. In particular, it is preferable that the temperature coefficient of resistance of the heater 113f is such that the peak current at the time of switching is smaller than the peak current (in other words, the peak power consumption) when the heater 113f is driven only by the high-level drive voltage, and the power consumption of the heater 113f when the drive voltage is switched is less than or equal to the power that can be supplied by the high-voltage converter 42.

[0165] (Second example of humidification control) Next, a second example of humidification control will be described with reference to Figure 7. Figure 7 is a timing chart showing the operation of the humidification control circuit 4 in the second example of humidification control. Unless otherwise specified, the main component of the humidification control is the control device 3.

[0166] In the first example of humidification control described above, the control device 3 performs a second example of humidification control when the heater 113f is driven by a high-level drive voltage and the temperature of the heater 113f drops rapidly. An example of a situation in which the temperature of the heater 113f drops rapidly is when water droplets generated in the evaporator 113c come into contact with the heater 113f.

[0167] (Time T ０ ~T １ Processing at time T ０ ~T １ In this case, the control device 3 sends a low-level switch circuit control signal to the high-voltage side control line CL1. Also, the control device 3, at time T in Figure 7, ０ ~T １ In this configuration, a high-level switch circuit drive signal is sent to the high-voltage drive line DL1.

[0168] In this state, the high-voltage side switch circuit 440 is in the ON state. Therefore, the heater 113f is connected to the high-voltage converter 42 and driven with a high-level drive voltage.

[0169] As shown in Figure 7, time T ０ ~T １ At time T in Figure 7, the temperature of heater 113f is decreasing. １ In this case, the temperature of the heater 113f falls below the first threshold (110°C in this example).

[0170] (Time T １ Processing in the above) The control device 3 processes at time T in Figure 7. １ In this state, the heater 113f is stopped. At this time, the control device 3 controls the switch circuit 44 to disconnect the heater 113f from the high-voltage converter 42 and the low-voltage converter 43.

[0171] The control device 3 stops the heater 113f at time T in Figure 7. １ In this case, a low-level switch circuit control signal is sent to the high-voltage side control line CL1. Also, in order to stop the heater 113f, the control device 3 is sent at time T in Figure 7. １In this process, a Low-level switch circuit drive signal is sent to the high-voltage side drive line DL1.

[0172] Accordingly, the high-voltage side switch circuit 440 changes at time T in FIG. 7 １ from an ON state to an OFF state. Therefore, the heater 113f is disconnected from the high-voltage converter 42.

[0173] Furthermore, the control device 3, at time T in FIG. 7 １ sends a Low-level switch circuit control signal to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 maintains the OFF state.

[0174] Furthermore, the control device 3, at time T in FIG. 7 １ sends a Low-level switch circuit drive signal to the low-voltage side drive line DL2. Accordingly, the low-voltage side drive switch circuit 442 changes at time T in FIG. 7 １ from an ON state to an OFF state.

[0175] In the state of the switch circuit 44 at time T in FIG. 7 as described above １ , the heater 113f is disconnected from both the high-voltage converter 42 and the low-voltage converter 43. Therefore, the heater 113f stops operating.

[0176] In other words, in the second example of humidification control, when the heater 113f is driven by a high-level drive voltage and the temperature of the heater 113f becomes lower than a first threshold value (110°C in this example), the control device 3 stops the voltage supply to the heater 113f.

[0177] As a result, it is possible to prevent the heater 113f from being connected to the low-voltage converter 43 before being disconnected from the high-voltage converter 42. This can prevent an abnormal voltage from being applied to the low-voltage converter 43.

[0178] (Processing at time T ２ ) Next, the control device 3, at time T in FIG. 7 ２In this step, a High-level switch circuit control signal is sent to the high-voltage side control line CL1. In this state, the control device 3 sends a Low-level switch circuit drive signal to the high-voltage side drive line DL1.

[0179] Therefore, the high-voltage side switch circuit 440, at time T in FIG. 7 ２ , maintains an OFF state. At time T in FIG. 7 ２ , the heater 113f is disconnected from the high-voltage converter 42.

[0180] Furthermore, the control device 3, at time T in FIG. 7 ２ , sends a High-level switch circuit control signal to the low-voltage side control line CL2. Thereby, the low-voltage side control switch circuit 441 transitions from the OFF state to the ON state.

[0181] Furthermore, the control device 3, at time T in FIG. 7 ２ , sends a Low-level switch circuit drive signal to the low-voltage side drive line DL2. As a result, the low-voltage side drive switch circuit 442, at time T in FIG. 7 ２ , maintains an OFF state. Therefore, at time T in FIG. 7 ２ , the heater 113f is disconnected from the low-voltage converter 43.

[0182] (Processing at time T ３ ) Next, the control device 3, at time T in FIG. 7 ３ , sends a High-level switch circuit control signal to the high-voltage side control line CL1. In this state, the control device 3 sends a High-level switch circuit drive signal to the high-voltage side drive line DL1. Thereby, the high-voltage side switch circuit 440, at time T in FIG. 7 ３ , maintains an OFF state. Therefore, the heater 113f, at time T in FIG. 7 ３ , is disconnected from the high-voltage converter 42.

[0183] Furthermore, the control device 3, at time T in FIG. 7 ３ , sends a High-level switch circuit control signal to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 maintains the ON state.

[0184] Furthermore, the control device 3 controls the time T in Figure 7. ３ At this point, a high-level switch circuit drive signal is sent to the low-voltage drive line DL2. As a result, the low-voltage drive switch circuit 442 operates at time T in Figure 7. ３ In this state, it transitions from the OFF state to the ON state.

[0185] As a result, heater 113f is at time T in Figure 7. ３ In this configuration, it is connected to the low-voltage converter 43. In this state, the heater 113f is driven with a low-level drive voltage.

[0186] As described above, in this example, the heater 113f is driven at a low-level drive voltage after a second predetermined time has elapsed since the voltage supply to the heater 113f was stopped. The second predetermined time is T ３ -T １ That is the case.

[0187] In other words, in this example, time T in Figure 7 １ After a predetermined time has elapsed since the heater 113f was stopped, the heater 113f is disconnected from the high-voltage converter 42, connected to the low-voltage converter 43, and driven with a low-level drive voltage.

[0188] Furthermore, the control device 3 operates at time T in Figure 7. ３ The process to be carried out at time T in Figure 7 is ２ This may be carried out at time T in Figure 7. In this case, the heater 113f is at time T in Figure 7. ２ In this case, it is driven with a low-level drive voltage. In this case, the second predetermined time is T ２ -T １ That is the case.

[0189] (Time T ４ Processing in Figure 7) Next, time T ４ At this point, the temperature of the heater 113f becomes higher than the first threshold (110°C in this example). The control device 3 controls the heater at time T in Figure 7. ４ In this configuration, the heater 113f is driven with a high-level drive voltage.

[0190] In this process, the control device 3 controls the switch circuit 44 to connect the heater 113f to the high-voltage converter 42. The control device 3 also disconnects the heater 113f from the low-voltage converter 43.

[0191] The control device 3 drives the heater 113f with a high-level drive voltage, at time T in Figure 7. ４ In this configuration, a low-level switch circuit control signal is sent to the high-voltage side control line CL1.

[0192] Furthermore, in order to drive the heater 113f with a high-level drive voltage, the control device 3 operates at time T in Figure 7. ４ In this configuration, a high-level switch circuit drive signal is sent to the high-voltage drive line DL1.

[0193] As a result, the high-voltage side switch circuit 440 is activated at time T in Figure 7. ４ +D １ In this case, it transitions from the OFF state to the ON state. Here, D １ This is the delay time caused by the delay circuit 443 (see Figure 4). In other words, the timing at which the high-voltage side switch circuit 440 turns ON is time T ４ D １ It will be delayed by just that much.

[0194] Furthermore, the control device 3 controls the time T in Figure 7. ４ In this state, a low-level switch circuit control signal is sent to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 transitions from the ON state to the OFF state.

[0195] Furthermore, the control device 3 controls the time T in Figure 7. ４ In this configuration, a high-level switch circuit drive signal is sent to the low-voltage drive line DL2. As a result, the low-voltage drive switch circuit 442 maintains the ON state.

[0196] Time T in Figure 6 as described above ４ In the state of the switch circuit 44 shown in Figure 6, the heater 113f is disconnected from the low-voltage converter 43. ４ In the state of the switch circuit 44, the heater 113f is not connected to the high-voltage converter 42.

[0197] Then, heater 113f is at time T in Figure 7. ４ +D １ At this point, it is connected to the high-voltage converter 42. Thus, in this example, at time T in Figure 7, ４ In this configuration, the heater 113f is prevented from being connected to both the low-voltage converter 43 and the high-voltage converter 42 simultaneously. This prevents an abnormal voltage from being applied to the low-voltage converter 43.

[0198] Also, time T in Figure 7 ４ +D １ In this configuration, when the heater 113f is connected to the high-voltage converter 42, the heater 113f is driven with a high-level drive voltage.

[0199] As described above, in this example, when the temperature of heater 113f exceeds a first threshold (110°C in this example), heater 113f is disconnected from the low-voltage converter 43. Then, for a first predetermined time D １ After the specified time, the heater 113f is connected to the high-voltage converter 42 and driven with a high-level drive voltage.

[0200] (Time T ５ Processing in Figure 7) Next, time T ５ In this case, the temperature of the heater 113f reaches the target temperature (140°C in this example). Thus, in this example, when the temperature of the heater 113f exceeds the first threshold (110°C in this example), the control device 3 drives the heater 113f with a high-level drive voltage to raise the temperature of the heater 113f to the target temperature.

[0201] The control device 3 controls the time T in Figure 7. ５ In this state, the heater 113f is stopped. At this time, the control device 3 controls the switch circuit 44 to disconnect the heater 113f from the high-voltage converter 42 and the low-voltage converter 43.

[0202] Specifically, the control device 3 stops the heater 113f at time T in Figure 7. ５ In this configuration, a low-level switch circuit control signal is sent to the high-voltage side control line CL1.

[0203] Furthermore, the control device 3 stops the heater 113f at time T in Figure 7. ５ In this configuration, a low-level switch circuit drive signal is sent to the high-voltage drive line DL1.

[0204] As a result, the high-voltage side switch circuit 440 is activated at time T in Figure 7. ５ In this state, it transitions from the ON state to the OFF state.

[0205] Furthermore, the control device 3 controls the time T in Figure 7. ５ In this configuration, a low-level switch circuit control signal is sent to the low-voltage side control line CL2. As a result, the low-voltage side control switch circuit 441 remains in the OFF state.

[0206] Furthermore, the control device 3 controls the time T in Figure 7. ５ In this state, a low-level switch circuit drive signal is sent to the low-voltage side drive line DL2. As a result, the low-voltage side drive switch circuit 442 operates at time T in Figure 7. ５ In this state, it transitions from the ON state to the OFF state.

[0207] Time T in Figure 7 as described above ５ In the state of the switch circuit 44, the heater 113f is disconnected from the high-voltage converter 42 and the low-voltage converter 43. As a result, the heater 113f stops.

[0208] (Operation and Effects of the Second Example of Humidification Control) According to the second example of humidification control described above, when the heater 113f is driven with a high-level drive voltage and the temperature of the heater 113f drops rapidly, the temperature of the heater 113f can be raised to the target temperature. In this case, as with the first example of humidification control described above, it is possible to suppress the peak current when the drive voltage of the heater 113f is switched. Therefore, the high-voltage converter 42 can be miniaturized.

[0209] All disclosures in the specification, drawings, and abstract contained in the Japanese application No. 2025-052299, filed on 26 March 2025, are incorporated herein by reference.

[0210] The culture apparatus according to the present invention can be used for culturing various types of cells.

[0211] 1 Culture Apparatus 101 Box 101a Inner Box 101b Outer Box 101c Insulation Material 101d Culture Chamber 101e Opening 101f Shelf 101g Through Hole 102 Inner Door 103 Outer Door 104 Gasket 105 Cover 106 Machine Room 107 Electrical Box 108 Duct 108a Intake 108b Outlet 109 Gas Passage 110 Blower 111 Gas Supply Device 112 Heater for Culture Chamber 113 Humidifier 113a Tank 113b Pump 113c Evaporator 113d Discharge Pipe 113e Nozzle Component 113f Heater 113g Temperature Sensor 113h Evaporation Space 114 Operating Device 3 Control device 4 Humidification control circuit 41 Power supply 42 High voltage converter 43 Low voltage converter 44 Switch circuit 440 High voltage side switch circuit 441 Low voltage side control switch circuit 442 Low voltage side drive switch circuit 443 Delay circuit L1 High voltage side line L2 Low voltage side line CL1 High voltage side control line DL1 High voltage side drive line CL2 Low voltage side control line DL2 Low voltage side drive line

Claims

1. A culture apparatus comprising: an evaporator that generates steam and supplies the steam to a culture chamber; a heater that heats the evaporator; and a control unit that controls the heater, wherein the control unit switches the magnitude of the drive voltage of the heater according to the temperature of the heater to raise the temperature of the heater to a target temperature.

2. The culture apparatus according to claim 1, wherein the control unit drives the heater with a low-level drive voltage when the temperature is below a first threshold, and drives the heater with a high-level drive voltage when the temperature is above the first threshold.

3. The culture apparatus according to claim 2, wherein the control unit stops the heater when the temperature reaches the target temperature, and when the temperature falls below the target temperature by a first predetermined temperature while the heater is stopped, drives the heater with the high-level drive voltage to raise the temperature to the target temperature.

4. The culture apparatus according to claim 2, further comprising: a high-level power supply unit that supplies the high-level drive voltage to the heater; and a low-level power supply unit that supplies the low-level drive voltage to the heater, wherein the control unit disconnects the heater from the high-level power supply unit and connects it to the low-level power supply unit when the temperature is below the first threshold; and connects the heater to the high-level power supply unit and disconnects it from the low-level power supply unit when the temperature is greater than the first threshold.

5. The culture apparatus according to claim 4, wherein the control unit disconnects the heater from the low-level power supply unit when the temperature exceeds the first threshold, and connects the heater to the high-level power supply unit after a first predetermined time has elapsed.

6. The culture apparatus according to claim 2, wherein the control unit, while the heater is being driven with a high-level drive voltage, stops supplying voltage to the heater when the temperature falls below the first threshold, drives the heater with the low-level drive voltage after a second predetermined time has elapsed, and drives the heater with the high-level drive voltage when the temperature exceeds the first threshold to raise the temperature of the heater to the target temperature.

7. The culture apparatus according to claim 2, further comprising: a high-level power supply unit that supplies the high-level drive voltage to the heater; and a low-level power supply unit that supplies the low-level drive voltage to the heater, wherein the control unit disconnects the heater from the high-level power supply unit and the low-level power supply unit when the temperature falls below the first threshold while the heater is being driven by the high-level drive voltage; after a predetermined time has elapsed, connects the heater to the low-level power supply unit with the heater disconnected from the high-level power supply unit and drives the heater with the low-level drive voltage; and when the temperature exceeds the first threshold, disconnects the heater from the low-level power supply unit, connects the heater to the high-level power supply unit and drives the heater with the high-level drive voltage after a first predetermined time has elapsed.

8. The culture apparatus according to claim 1, wherein the heater has a positive temperature coefficient of resistance, the resistance value increases as the temperature rises.

9. A control method to be implemented in a culture apparatus comprising an evaporator that generates steam and supplies the steam to a culture chamber, and a heater that heats the evaporator, the control method comprising: a step of obtaining the temperature of the heater; and a step of switching the magnitude of the drive voltage of the heater according to the temperature to raise the temperature of the heater to a target temperature.

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