Heating apparatus and PID coefficient setting method for heating apparatus

Abstract

To provide a heating apparatus capable of improving accuracy of temperature control of a heated object and capable of shortening a PID coefficient setting time, and a PID coefficient setting method.SOLUTION: A heating apparatus comprises: a main heat source 10 and a sub heat source 20 which heat a heated object 100; a main heat source control device 60 which controls output of the main heat source 10; and a sub heat source control device 70 which controls output of the sub heat source 20. The main heat source control device 60 performs PID control on the output of the main heat source 10 in such a manner that a temperature of the heated object 100 becomes a predetermined target temperature profile P1, and the sub heat source control device 70 performs PID control on the output of the sub heat source 20 in such a manner that a temperature of the sub heat source 20 becomes a second target temperature profile P2 resulting from adding temperature offset ΔT to the target temperature profile P1. A PID coefficient of the main heat source control device 60 and a PID coefficient of the sub heat source control device 70 can be independently set by auto-tuning, and the temperature offset ΔT can be independently set.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a heating device having multiple heat sources and a method for setting PID coefficients of the heating device. [Background technology]

[0002] Conventionally, in the heat treatment of various articles, heat treatment devices and methods using two or more types of heat sources, such as a hot plate that heats by thermal conduction and a heat lamp that heats by thermal radiation, have been developed. For example, such heat treatment devices combine a hot plate capable of continuous heating with a heat lamp capable of rapid temperature rise to faithfully achieve the target temperature change over time (e.g., Patent Documents 1 to 3).

[0003] In such heating devices using two or more types of heat sources, there is a problem in that it is cumbersome to set the PID coefficients for PID control so that the temperature of the heated object follows the target temperature change over time (target temperature profile). In the conventional method, the PID coefficients are first set for each heat source so that the temperature of the heat source closely follows the target temperature profile. Then, the heated object is heated and the deviation between the temperature change of the heated object and the target temperature profile is confirmed. If the deviation is large, the PID control coefficients of each heat source are readjusted and the heated object is heated again to confirm whether the temperature change follows the target temperature profile. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-126002 A [Patent Document 2] JP 2017-072555 A [Patent Document 3] JP 2002-164299 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, this PID coefficient setting method has the problem that the deviation of the temperature change of the heated object from the target temperature profile does not converge easily, and it is necessary to repeatedly perform a temperature rise test to heat the heated object according to the target temperature profile, which takes time. In addition, since the temperature of the heated object is indirectly obtained by controlling the temperature of the heat source, there is a problem that an error is likely to occur with respect to the target temperature.

[0006] The present invention aims to solve the above problems and provide a heating device having multiple heat sources, capable of improving the accuracy of temperature control of an object to be heated, and capable of shortening the time required to set the PID coefficients, and a method for setting the PID coefficients of the heating device. [Means for solving the problem]

[0007] In order to solve the above problems, the heating device of the present invention is a heating device comprising a main heat source and a secondary heat source for heating an object to be heated, a main heat source control device for controlling the output of the main heat source, and a secondary heat source control device for controlling the output of the secondary heat source, wherein the main heat source control device PID controls the output of the main heat source so that the temperature of the object to be heated conforms to a predetermined target temperature profile, and the secondary heat source control device PID controls the output of the secondary heat source so that the temperature of the secondary heat source conforms to a second target temperature profile obtained by adding a temperature offset to the target temperature profile, and the PID coefficient of the main heat source control device, the PID coefficient of the secondary heat source control device, and the temperature offset can be set independently.

[0008] The main heat source may be a heat source that heats an object to be heated by thermal radiation, and the secondary heat source may be a heat source that heats an object to be heated by thermal conduction or proximity heating.

[0009] The main heat source may be a lamp heater, and the secondary heat source may be a ceramic heater.

[0010] The temperature of the object to be heated may be measured by a non-contact temperature sensor.

[0011] The method for setting PID coefficients of a heating device of the present invention is a method for setting PID coefficients of a heating device including a main heat source and a secondary heat source for heating an object to be heated, a main heat source control device that PID controls an output of the main heat source based on a temperature of the object to be heated, and a secondary heat source control device that PID controls an output of the secondary heat source based on the temperature of the secondary heat source, a first step of calculating and setting optimal PID coefficients for the auxiliary heat source control device from a difference between an actual temperature profile of the auxiliary heat source and the second target temperature profile obtained by adding a temperature offset to the target temperature profile when the object to be heated is heated by the auxiliary heat source with the second target temperature profile; a second step of heating the object by PID controlling the temperature of the secondary heat source with the secondary heat source control device based on the second target temperature profile and the set PID coefficient, and at the same time calculating and setting an optimal PID coefficient for the main heat source control device from a difference between an actual temperature profile of the object to be heated and the target temperature profile when the object to be heated is heated with the main heat source with the target temperature profile.

[0012] In the above PID coefficient setting method, the main heat source may be a heat source that heats an object to be heated by thermal radiation or hot air, and the secondary heat source may be a heat source that heats an object to be heated by thermal conduction or proximity heating.

[0013] In the above PID coefficient setting method, the temperature of the object to be heated may be measured by a non-contact temperature sensor.

[0014] In the PID coefficient setting method, the PID coefficients may be acquired and set by utilizing an auto-Turing function of the main heat source control device and the sub-heat source control device.

[0015] The heating method of the present invention uses a heating device including a main heat source and a secondary heat source for heating an object to be heated, a main heat source control device that performs PID control of the output of the main heat source based on the temperature of the object to be heated, and a secondary heat source control device that performs PID control of the output of the secondary heat source based on the temperature of the secondary heat source, This is a method for heating the object to be heated while controlling the outputs of the main heat source and the auxiliary heat source based on the PID coefficients set by any of the PID coefficient setting methods described above. In addition, since the optimum PID coefficients and optimum temperature offsets vary depending on the shape and dimensions of the object to be heated and the temperature profile of the heat treatment, it is preferable to set them for each object to be heated and each temperature profile of the heat treatment. Effect of the Invention

[0016] According to the heating device of the present invention, the output of the main heat source is PID controlled based on the temperature of the object to be heated, so the difference between the actual temperature of the object to be heated and the target temperature is small. Also, since the target temperature profile of the sub heat source (second target temperature profile) is set lower than the target temperature profile of the main heat source, an appropriate auxiliary effect, i.e., a relative cooling effect or relative heating effect by the sub heat source, is exerted, and the accuracy of following the target temperature profile can be improved.

[0017] Furthermore, according to the PID coefficient setting method of the present invention, the target temperature profile (second target temperature profile) of the secondary heat source at the time of setting is set to a temperature different from that of the main heat source, which provides an appropriate auxiliary effect and improves the accuracy of tracking the target temperature profile. As a result, satisfactory tracking accuracy can be obtained with a smaller number of PID coefficient setting operations, and the PID coefficient setting time can be shortened. [Brief description of the drawings]

[0018] [Figure 1] 1 is a conceptual diagram showing a heating device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram showing temperature control of the heating device in FIG. [Diagram 3] 2 is a flowchart showing a method for setting PID coefficients of the heating device of FIG. 1. [Figure 4] 2 is a graph showing the ability of the heating device of FIG. 1 to follow a target temperature profile. [Diagram 5] 11 is a graph showing the ability of a conventional heating device to follow a target temperature profile. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] (heating device) A heating device 1 according to an embodiment of the present invention will be described below with reference to Fig. 1 to Fig. 4. As shown in Fig. 1 and Fig. 2, the heating device 1 includes a main heat source 10, an auxiliary heat source 20, a heated object temperature sensor 30, an auxiliary heat source temperature sensor 40, a chamber 50, a main heat source control device 60, an auxiliary heat source control device 70, and a host control device 80. The heating device 1 shown in Fig. 1 is a portable testing device, and is configured so that the loading and unloading of the heated object 100 and the opening and closing of an opening / closing lid 53 of the chamber 50, which will be described later, are performed manually.

[0020] In this embodiment, the main heat source 10 is a halogen lamp heater (hereinafter also referred to as "halogen lamp heater 10") that heats the object to be heated by thermal radiation. By using the halogen lamp heater 10, it becomes possible to rapidly increase the temperature of the object to be heated 100, and it becomes easier to accurately follow the target temperature profile. In this specification, the "temperature profile" refers to the shape of the curve of the temperature change over time. This halogen lamp heater 10 is a lamp that has a high output and a long life by introducing a small amount of halogen gas in addition to an inert gas inside a substantially circular bulb. Light from the substantially circular bulb can be irradiated onto each surface of the heated object 100, and the inner surface 53a of the opening / closing lid 53 of the chamber 50 described later acts as a reflecting mirror, and the reflected light from this inner surface 53a can also be used, enabling efficient heating. Moreover, the same effect can be obtained even if hot air is used as the main heat source instead of the halogen lamp heater.

[0021] The auxiliary heat source 20 is a heat source that heats an object to be heated by thermal conduction or proximity heating, and in this embodiment, a ceramic heater (hereinafter also referred to as "ceramic heater 20") is used. This ceramic heater 20 is a heater that accumulates heat generated by passing electricity through a built-in heating wire 21 (not shown) in a ceramic hot plate 22, and conducts the heat to the object to be heated 100 placed on this hot plate 22 to heat it. Such a heat source allows continuous heating, and the temperature of the object to be heated 100 can be controlled by controlling the temperature of the heat source, i.e., the ceramic heater 20 itself. However, the heating is not limited to the thermal conduction heating in which the object to be heated 100 is placed on the hot plate 22 as described above, but proximity heating may be performed in which the object to be heated 100 is placed facing the hot plate 22 at a slight distance (for example, about 0.1 to 3 mm), and the same effect as above can be obtained.

[0022] The heated object temperature sensor 30 is a sensor that measures the temperature of the heated object 100, and in this embodiment, an infrared sensor, which is a non-contact temperature sensor, is used. This heated object temperature sensor 30 is disposed in an observation window 53b in the center of the opening and closing lid 53 of the chamber 50 described later, and measures the temperature of the heated object 100 by detecting the infrared radiation intensity of the heated object 100 through this observation window 53b. This makes it unnecessary to attach and detach the heated object temperature sensor 30 to the heated object 100, making it easy to replace the heated object 100. However, the heated object temperature sensor 30 is not limited to a non-contact sensor such as an infrared sensor, and any sensor that can measure the temperature of the heated object 100 may be used, and may be a contact sensor such as a thermocouple, a thermistor, or a resistance temperature detector.

[0023] The auxiliary heat source temperature sensor 40 is a sensor that is built into the ceramic heater 20, which is the auxiliary heat source 20, and detects its temperature. In this embodiment, a thermocouple is used. However, the auxiliary heat source temperature sensor 40 is not limited to a thermocouple, and any sensor that can measure the temperature of the ceramic heater 20 may be used, including a contact sensor such as a thermistor or a resistance temperature detector, or a non-contact sensor such as an infrared sensor.

[0024] The chamber 50 is a container that holds the object 100 to be heated and keeps it at a predetermined high temperature. An inert gas that prevents chemical reactions such as oxidation of the object to be heated, or a reactive gas that causes a chemical reaction may be supplied to the chamber 50. In this embodiment, the chamber 50 includes a briefcase-shaped, box-shaped chamber body 51 with an open top, an openable lid 53 that is connected to the chamber body 51 via a hinge 52 and opens and closes the top, and two buckles 54 that fix the openable lid 53 in a closed state. The halogen lamp heater 10, which is the main heat source, and the ceramic heater 20, which is the auxiliary heat source, are also arranged in the chamber 50. However, the present invention is not limited to this form, and for example, the halogen lamp heater 10 may be arranged outside the chamber and light may be irradiated from a transparent window of the chamber to heat the object to be heated. During the heating process of the heating device 1, the openable lid 53 is closed to seal the inside of the chamber 50, while the openable lid 53 is opened before and after the heating process to allow the object to be heated 100 to be carried in and out.

[0025] The main heat source control device 60 is a device that controls the output of the main heat source 10, and performs PID control of the output of the main heat source 10 based on the temperature of the object 100 to be heated. The main heat source control device 60 has a processor (not shown), an output adjustment circuit (not shown) for the main heat source 10, and a signal input interface (not shown) for the heated object temperature sensor 30. The output adjustment circuit has, for example, a thyristor that controls the on / off of the power supply, and obtains a desired output by adjusting the duty ratio of this on / off control. The main heat source control device 60 is configured to receive a target temperature (target temperature profile P1) from a higher-level control device 80 described later, calculate the difference between the target temperature and the temperature of the heated object 100 read by the heated object temperature sensor 30, and perform PID control of the output of the main heat source 10 based on preset PID coefficients (Kp, Ti, Td). In addition, the main heat source control device 60 has an auto-tuning function that calculates and sets the optimal PID coefficients (Kp1, Ti1, Td1) of the main heat source control device 60 from the difference between the actual temperature profile of the heated object 100 and the target temperature profile P1 when heating is performed by the main heat source 10 with the target temperature profile P1.

[0026] The auxiliary heat source control device 70 is a device that controls the output of the auxiliary heat source 20, and performs PID control of the output of the auxiliary heat source 20 based on the temperature of the auxiliary heat source 20. The auxiliary heat source control device 70 also has a processor (not shown), an output adjustment circuit (not shown) for the auxiliary heat source 20, and a signal input interface (not shown) for the auxiliary heat source temperature sensor 40. The output adjustment circuit has, for example, a thyristor that controls the on / off of the power supply, and the desired output is obtained by adjusting the duty ratio of this on / off control. The secondary heat source control device 70 is configured to receive a second target temperature profile P2, which is obtained by adding a temperature offset ΔT to the target temperature profile P1, from a higher-level control device 80 described later, calculate the difference between the second target temperature profile and the temperature of the secondary heat source 20 read by the secondary heat source temperature sensor 40, and perform PID control of the output of the secondary heat source 20 based on preset PID coefficients (Kp, Ti, Td). The auxiliary heat source control device 70 has an auto-tuning function that calculates and sets optimal PID coefficients (Kp2, Ti2, Td2) of the auxiliary heat source control device 70 from the difference between the actual temperature profile of the auxiliary heat source 20 and the target temperature profile P2 when heating is performed by the auxiliary heat source 20 with the target temperature profile P2.

[0027] The upper controller 80 is a device that controls the operation of the entire heating device, and has a communication function with an operation input device (not shown) as a user interface, a display device (not shown), an external computer (not shown), etc. The upper controller 80 creates a temperature profile for the heating process according to instructions from the operation input device (not shown) or the external computer (not shown), and transmits the temperature profile to the main heat source controller 60 and the auxiliary heat source controller 70 to instruct them to execute the process. The operation input device (not shown) can also be used to set the PID coefficients (Kp, Ti, Td) of the main heat source controller 60 and the auxiliary heat source controller 70, and the temperature offset ΔT between the two controllers. The host controller 80 can also instruct the main heat source controller 60 and the auxiliary heat source controller 70 to execute their respective auto-tuning functions. In addition, in the PID coefficient setting method of this embodiment described below, the host controller 80 may, for example, manually set step (1) and then have the main heat source controller 60 and the auxiliary heat source controller 70 automatically execute steps (2) and (3) in sequence.

[0028] It is not necessary for the main heat source control device 60, the auxiliary heat source control device 70, and the upper control device 80 to be physically independent devices. For example, each digital control portion may be a program module in a single computer.

[0029] Next, the operation of the heating device 1 of this embodiment configured as above will be described. First, with the opening / closing lid 53 of the chamber 50 open, the object to be heated 100 is manually carried into the chamber 50 and placed on the ceramic heater 20, which is the secondary heat source. Next, the opening / closing lid 53 of the chamber 50 is closed, and the heating process program (target temperature profile P1) to be executed is selected on the operation input device (not shown) or display device (not shown) of the heating device 1, and a process start operation is performed. Then, the halogen lamp heater 10, which is the main heat source, is turned on, and electricity is applied to the ceramic heater 20, which is the secondary heat source, and the heating process is started. In this heating process, the main heat source control device 60 PID controls the output of the main heat source 10 so that the temperature of the heated object 100 conforms to a predetermined target temperature profile P1, and the auxiliary heat source control device 70 PID controls the output of the auxiliary heat source 20 so that the temperature of the auxiliary heat source 20 conforms to a second target temperature profile P1 obtained by adding a temperature offset ΔT to the target temperature profile P1. When the heating process is completed, a cooling process is performed, for example, by air cooling, and the open / close lid 53 of the chamber 50 opens, making it possible to manually remove the object 100 to be heated.

[0030] As described above, the heating device 1 of this embodiment is a portable testing device, and is configured so that the loading and unloading of the object 100 and the opening and closing of the openable cover 53 of the chamber 50 are performed manually, but in a mass production device, these operations may be performed automatically. When the heating device 1 is configured as a mass production device, it is preferable that the shape of the chamber 50 is formed taking into consideration heat retention and airtightness, and the size of the openable cover 53 is limited to a size necessary and sufficient for loading and unloading the object 100. In addition, the upper control device 80 may have a communication function with a transport device for the object (not shown) and the like, so as to be compatible with factory automation.

[0031] According to the heating device 1 of this embodiment, the output of the main heat source 10 is PID controlled based on the temperature of the object 100 to be heated, so the difference between the actual temperature of the object 100 and the target temperature is small. In addition, the target temperature profile (second target temperature profile P2) of the auxiliary heat source 20 is set lower than the target temperature profile P2 of the main heat source, so that an appropriate auxiliary effect, that is, a relative cooling effect or relative heating effect by the auxiliary heat source, works, and the accuracy of following the target temperature profile P1 can be improved. Figure 4 is a graph showing the ability of the heating device of this embodiment to follow the target temperature profile, and when compared with the graph of the conventional heating device shown in Figure 5 showing the ability of the heating device to follow the target temperature profile, it can be seen that the accuracy of following is improved.

[0032] (How to set PDI coefficient) Next, a method for setting the PID coefficients of the heating device 1 of this embodiment will be described with reference to FIG. (1) Temperature offset setting The temperature offset ΔT is the target temperature difference between the target temperature of the sub-heat source 20 and the target temperature of the main heat source 10. Since the optimal value of this temperature offset ΔT differs depending on the shape, size, heat capacity, etc. of the object to be heated 100, the optimal value is determined by experiment or the like and set for each object to be heated 100. However, the temperature offset ΔT does not affect the final heating accuracy of the object to be heated 100 even if it is not optimized too strictly.

[0033] (2) First step First, the object to be heated 100 is heated using only the secondary heat source 20 with a second target temperature profile P2 obtained by adding a temperature offset ΔT to the target temperature profile P1, and the optimal PID coefficients (Kp2, Ti2, Td2) of the secondary heat source control device 70 are calculated and set from the difference between the actual temperature profile of the secondary heat source 20 at that time and the second target temperature profile P2. The target temperature profile P1 and the second target temperature profile P2 are step-like temperature profiles. In this heating, the output of the auxiliary heat source 20 is PID-controlled with default PID coefficients so that the temperature of the auxiliary heat source 20 detected by the auxiliary heat source temperature sensor 40 becomes the second target temperature profile P2. From the difference between the actual temperature profile of the auxiliary heat source 20 and the second target temperature profile, the auto-tuning function of the auxiliary heat source control device 70 is used to calculate optimal PID coefficients (Kp2, Ti2, Td2). The calculation of the optimal PID coefficients in this auto-tuning function can be performed by any known calculation method, such as the Ziegler-Nichols step response method or the CHR method.

[0034] (3) Second step Next, the temperature of the secondary heat source 20 is PID controlled by the secondary heat source control device 70 using a second target temperature profile P2 based on the set PID coefficients (Kp2, Ti2, Td2) to heat the object to be heated 100, and at the same time, optimal PID coefficients (Kp1, Ti1, Td1) for the main heat source control device 60 are calculated and set from the difference between the actual temperature profile of the object to be heated 100 and the target temperature profile P1 when the object to be heated 100 is heated by the main heat source 10 using the target temperature profile P1. In heating by the main heat source 10, the output of the main heat source 10 is PID-controlled with default PID coefficients so that the temperature of the main heat source 10 detected by the heated object temperature sensor 30 becomes the target temperature profile P1. From the difference between the actual temperature profile of the heated object 100 and the target temperature profile P1, the auto-tuning function of the main heat source control device 60 is used to obtain and set the optimal PID coefficients (Kp1, Ti1, Td1). The calculation of the optimal PID coefficients in this auto-tuning function can be performed by any known calculation method, such as the Ziegler-Nichols step response method or the CHR method.

[0035] After this second step, if necessary, the temperature of the auxiliary heat source 20 is controlled to the second target temperature profile P2 while simultaneously heating the object 100 to the target temperature profile P1 with the main heat source 10, and it is confirmed that the difference between the actual temperature profile of the object 100 to be heated and the target temperature profile P1 at this time is within the target range. If it is within the target range, the setting is terminated, and if it is not within the target range, the first and second steps may be repeated.

[0036] According to the PID coefficient setting method of this embodiment, the output of the main heat source is PID controlled based on the temperature of the object to be heated during setting, so that the difference between the actual temperature of the object to be heated and the target temperature can be reduced. Also, since the target temperature profile of the sub heat source (second target temperature profile P2) is set to a temperature different from the target temperature profile P1 of the main heat source, an appropriate auxiliary effect, i.e., a relative cooling effect or a relative heating effect by the sub heat source, works and the tracking accuracy of the target temperature profile is improved, so that a satisfactory tracking accuracy can be obtained with a small number of PID coefficient setting times, and the PID coefficient setting time can be shortened.

[0037] (Heating method) The heating method of this embodiment is a method of using a heating device 1 including a main heat source 10 and a secondary heat source 20 for heating an object to be heated 100, a main heat source control device 60 for PID controlling the output of the main heat source 10 based on the temperature of the object to be heated 100, and a secondary heat source control device 70 for PID controlling the output of the secondary heat source 20 based on the temperature of the secondary heat source 20, and heating the object to be heated while controlling the output of the main heat source and the secondary heat source based on the PID coefficients set by the above-mentioned PID coefficient setting method. The optimum PID coefficients and optimum temperature offset ΔT vary depending on the shape and dimensions of the object 100 to be heated and the temperature profile of the heat treatment, and are therefore preferably set for each object 100 to be heated and each temperature profile of the heat treatment.

[0038] According to the heating method of the present invention, the effects of the heating device 1 of the present embodiment described above and the effects of the PID coefficient setting method of the present embodiment described above can be obtained, and the heating accuracy of the heated object 100 can be improved, which contributes to improving the quality of the product. In addition, the PID coefficient setting time can be shortened, which improves the device operating rate and improves productivity.

[0039] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific examples, and various modifications and variations are possible within the scope of the gist of the present invention described in the claims.

[0040] For example, in each of the above embodiments, one main heat source and one sub-heat source are used, but two or more types of heat sources may be used in combination as the sub-heat source. For example, a ceramic heater of a conductive heating type and a hot air heater of a hot air heating type may be used as the sub-heat source, and PID control may be performed so that the temperature of the hot air becomes the second target temperature profile. [Industrial Applicability]

[0041] The heating device and the PID setting method for the heating device according to the present invention can be widely used in the industrial fields of semiconductor and automobile part manufacturing. [Explanation of symbols]

[0042] 1 Heating device 10 Main heat source (halogen lamp heater) 20 Secondary heat source (ceramic heater) 22 Hot plate 30 Heated object temperature sensor 40 Secondary heat source temperature sensor 50 Chamber 51 Chamber body 52 Hinge 53 Opening and closing lid 53a Inside 53b Observation window 54 Buckle 60 Main heat source control device 70 Secondary heat source control device 80 Upper control device 100 Heated object P1 Target temperature profile P2 Second target temperature profile ΔT Temperature Offset

Claims

1. A heating device including a main heat source and a secondary heat source for heating an object to be heated, a main heat source control device for controlling the output of the main heat source, and a secondary heat source control device for controlling the output of the secondary heat source, The main heat source control device performs PID control of the output of the main heat source so that the temperature of the object to be heated conforms to a predetermined target temperature profile, the auxiliary heat source control device performs PID control on an output of the auxiliary heat source so that the temperature of the auxiliary heat source becomes a second target temperature profile obtained by adding a temperature offset to the target temperature profile, A heating device in which a PID coefficient of the main heat source control device, a PID coefficient of the sub heat source control device, and the temperature offset can be set independently.

2. 2. The heating device according to claim 1, wherein the main heat source is a heat source that heats the object to be heated in a non-contact manner, and the secondary heat source is a heat source that heats the object to be heated by thermal conduction or proximity heating.

3. 3. The heating device according to claim 2, wherein the main heat source is a lamp heater, and the auxiliary heat source is a ceramic heater.

4. The heating device according to claim 1 , wherein the temperature of the object to be heated is measured by a non-contact or contact temperature sensor.

5. A method for setting a PID coefficient of a heating device including a main heat source and a secondary heat source for heating an object to be heated, a main heat source control device that performs PID control of an output of the main heat source based on a temperature of the object to be heated, and a secondary heat source control device that performs PID control of an output of the secondary heat source based on the temperature of the secondary heat source, comprising: a first step of calculating and setting an optimal PID coefficient for the auxiliary heat source control device from a difference between an actual temperature profile of the auxiliary heat source and the second target temperature profile obtained by adding a temperature offset to the target temperature profile when the object to be heated is heated by the auxiliary heat source with the second target temperature profile; a second step of heating the object by PID controlling the temperature of the secondary heat source with the second target temperature profile using the secondary heat source control device based on the set PID coefficient, and at the same time calculating and setting an optimal PID coefficient for the main heat source control device from a difference between an actual temperature profile of the object to be heated and the target temperature profile when the object to be heated is heated by the main heat source with the target temperature profile.

6. 6. The PID coefficient setting method according to claim 5, wherein the main heat source is a heat source that heats the object by thermal radiation, and the secondary heat source is a heat source that heats the object by thermal conduction or proximity heating.

7. The PID coefficient setting method according to claim 5 , wherein the temperature of the object to be heated is measured by a non-contact or contact temperature sensor.

8. The PID coefficients are obtained and set by the PID coefficient setting method according to claim 5, utilizing the auto-turing function of the temperature regulator.

9. A heating device is used that includes a main heat source and a secondary heat source for heating an object to be heated, a main heat source control device that performs PID control of the output of the main heat source based on the temperature of the object to be heated, and a secondary heat source control device that performs PID control of the output of the secondary heat source based on the temperature of the secondary heat source, A heating method for heating the object while controlling outputs of the main heat source and the auxiliary heat source based on a PID coefficient set by the PID coefficient setting method according to any one of claims 5 to 8.

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