Induction heating device, control method, and program

Abstract

To improve the quality of a member having a prescribed length to be heat-treated by induction heating.SOLUTION: An induction heating device according to the present disclosure includes a conveying unit that conveys a member having a predetermined length in a conveying direction set along a longitudinal direction, a heating unit that inductively heats a part of the member being conveyed, a detection unit that detects a state of the member at a heating position, and a control unit that performs first control for controlling a conveying speed of the member relative to the heating unit or second control for controlling an output of the heating unit based on a detection result of the state of the member. As a first control, the control means controls the moving speed of the heating means to control the relative conveying speed to the heating means at the heating place of the member.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an induction heating device, a control method, and a program. [Background technology]

[0002] Patent Document 1 describes an induction heating device that uses induction heating to perform heat treatment such as quenching or coating on long, tubular or cylindrical metal members. Specifically, the induction heating device in Patent Document 1 includes a conveying roller that conveys the long metal member and an induction coil that surrounds a portion of the metal member, and performs heat treatment by induction heating while conveying the metal member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-020038 Summary of the Invention [Problem to be solved by the invention]

[0004] However, as described in the above-mentioned Patent Document 1, when a long metal component is heat-treated while being transported, there is a risk of overheating or insufficient heating during induction heating depending on the condition of the metal component in the longitudinal direction. As a result, it is difficult to heat-treat the entire component having a predetermined length to the desired state, and the quality of the heat-treated component cannot be improved.

[0005] Therefore, one of the objects of the present disclosure is to solve the above-mentioned problem that it is not possible to improve the quality of a member having a predetermined length that is heat-treated by induction heating. [Means for solving the problem]

[0006] An induction heating device according to one embodiment of the present disclosure includes: a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; a detection means for detecting a state of the heated portion of the member; a control means for performing a first control for controlling a relative transport speed of the member with respect to the heating means or a second control for controlling an output of the heating means based on the detection result of the state of the member; Equipped with the heating means is movable in the conveying direction and in a direction opposite to the conveying direction, the control means controls a moving speed of the heating means as the first control, thereby controlling a transport speed of the heating portion of the member relative to the heating means; The structure is as follows. [Effects of the Invention]

[0007] By being configured as described above, the present disclosure can improve the quality of a member having a predetermined length that is heat treated by induction heating. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram showing an example of the configuration of an induction heating device according to the present disclosure. [Figure 2] 1 is a block diagram showing an example of the configuration of an induction heating device according to the present disclosure. [Figure 3] 10 is a flowchart illustrating an example of a processing operation in the induction heating device according to the present disclosure. [Figure 4] 1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. [Figure 5] 1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. [Figure 6] 10 is a flowchart illustrating an example of a processing operation in the induction heating device according to the present disclosure. [Figure 7]1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. [Figure 8] 1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. [Figure 9] 1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. [Figure 10] 10 is a flowchart illustrating an example of a processing operation in the induction heating device according to the present disclosure. [Figure 11] 10 is a flowchart illustrating an example of a processing operation in the induction heating device according to the present disclosure. [Figure 12] 10 is a flowchart illustrating an example of a processing operation in the induction heating device according to the present disclosure. [Figure 13] 1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. [Figure 14] 1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. [Figure 15] 1 is a diagram showing an example of a process in an induction heating device according to the present disclosure. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Summary of this disclosure> The induction heating device disclosed herein uses induction heating to perform heat treatments such as quenching and coating on a metal member having a predetermined length. When a metal member having a predetermined length is transported and induction heated along its longitudinal direction, the heat treatment conditions may vary depending on the condition of each heating point along the metal member's longitudinal direction, potentially preventing high-quality heat treatment from being achieved overall. To address this issue, the present disclosure is configured to control heating according to the condition of the heating points on the metal member.

[0010] For example, the induction heating device according to the present disclosure is configured to change the conveying speed of the metal member relative to the heating means in accordance with the temperature, diameter, etc., of the heated portion of the metal member. As an example, the induction heating device is configured to increase the conveying speed of the metal member relative to the heating means when the temperature of the heated portion of the metal member is higher than the target value or the diameter of the metal member is decreasing, which could result in overheating. Also, as an example, the induction heating device is configured to decrease the conveying speed of the metal member relative to the heating means when the temperature of the heated portion of the metal member is lower than the target value or the diameter of the metal member is increasing, which could result in underheating.

[0011] Furthermore, for example, the induction heating device according to the present disclosure is configured to control the conveyance speed of the metal member relative to the heating means or the output of the heating means in accordance with the condition of the metal member at the heated point, such as the diameter of the metal member. As one example, the induction heating device controls the conveyance speed of the metal member relative to the heating means to change when the change in diameter of the metal member at the heated point is greater than a preset reference. As another example, the induction heating device controls the output of the heating means to change when the change in diameter of the metal member at the heated point is smaller than a preset reference.

[0012] A specific example of an induction heating device according to the present disclosure will be described below in the following embodiment. Note that in the following embodiment, a case will be described in which the temperature and diameter are detected as the state of the heated portion of the metal member, but the detected state of the metal member includes the material and thickness of the metal member itself, the material of the coating, and the like at the heated portion of the metal member, and therefore includes any state.

[0013] First Embodiment A first embodiment of the present disclosure will be described with reference to the drawings, which may be relevant to any embodiment.

[0014] [composition] Fig. 1 shows a schematic diagram of an induction heating device 1. The induction heating device 1 is configured with a PLC (Programmable Logic Controller) 10, a high-frequency power supply 20, a sensor 30, rollers 40a and 40b, an induction heating coil 50, a cooling device (not shown), and the like. The induction heating device 1 performs heat treatment on a workpiece W, which is a metal member having a predetermined length as shown in Fig. 1. Each component will be described in detail below.

[0015] The workpiece W is a cylindrical or columnar metal member, and is a rod-like member having a predetermined length. The workpiece W in this embodiment is formed, for example, with its outer diameter varying at predetermined locations in the longitudinal direction. For example, in the example of FIG. 1, the workpiece W has a larger diameter at the center than at the end portions at positions a predetermined distance from both ends in the longitudinal direction.

[0016] However, the workpiece W is not necessarily limited to being formed in a cylindrical or columnar shape, but may be formed in a multi-tubular or polygonal columnar shape including a square tube or a square column, and may have any cross-sectional shape perpendicular to the longitudinal direction. Furthermore, although the workpiece W is a member mainly made of a metal member, it may also be a member mainly made of a material other than metal.

[0017] The PLC 10 includes a storage unit 10a and a control unit 10b. The storage unit 10a is configured, for example, with a volatile storage device such as a RAM or a non-volatile storage device such as a HDD, and stores programs and data for executing various functions of the PLC 10. As will be described later, the storage unit 10a includes a target value storage unit 10aa and a shape storage unit 10ab, as shown in FIG. 2.

[0018] The control unit 10b is configured with a computer equipped with an arithmetic device such as a CPU (Central Processing Unit), MPU (Micro Processing Unit), or ASIC (Application Specific Integrated Circuit), and executes various sequence controls by reading programs stored in the storage unit 10a. Note that, as will be described later, the control unit 10b executes the programs to configure an acquisition unit 10ba, a determination unit 10bb, and a heating control unit 10bc shown in FIG. 2, and realize the functions described below. The functions realized by the control unit 10b will be described in detail when explaining the operation.

[0019] High frequency power supply 20 (heating means) has a built-in inverter circuit that generates high frequency current and supplies AC current at a predetermined frequency (e.g., 20 kHz) to coil 50 (heating means). Control unit 10b is connected to high frequency power supply 20 and controls the amount and timing of power supply.

[0020] The sensor 30 (detection means) has a temperature sensor 30a (detection means) and a laser sensor 30b (detection means), and is installed at a position according to each specification. The sensor 30 can be, for example, a non-contact sensor to avoid damage when materials are carried in and out or during heat treatment.

[0021] The temperature sensor 30a measures the surface temperature (temperature information) of the workpiece W that has been heat-treated by induction heating (high-frequency induction heating) and has just passed through the coil 50. The measurement point on the workpiece W can be, for example, a position facing the center of the coil 50 in the longitudinal direction. This allows the temperature sensor 30a to detect the temperature of the heated point on the workpiece W. The temperature sensor 30a may be, for example, a radiation thermometer or the like that can detect the surface temperature of the workpiece W, or any measuring device that can detect temperature contact or non-contact.

[0022] The laser sensor 30b may be, for example, a transmission type laser discrimination sensor capable of detecting the diameter of the workpiece W. By using such a transmission type laser discrimination sensor, the outer diameter of the workpiece W can be measured with high accuracy regardless of the translucency of the workpiece W. The laser sensor 30b may be installed near the coil 50, or may be installed at a position a predetermined distance from the coil 50. By this means, by referring to the distance from the coil 50, the diameter of the workpiece W measured by the laser sensor 30b can be detected as the diameter of the heated area. The laser sensor 30b may be any measuring device capable of detecting the diameter of the workpiece W with or without contact.

[0023] The rollers 40a, 40b (conveying means) have two conveying rollers 40a and multiple receiving rollers 40b, which are arranged at intervals so as not to cause bending of the workpiece W. The conveying rollers 40a convey the workpiece W into the coil 50 in one direction (hereinafter referred to as the "conveying direction C"), which is the longitudinal direction of the workpiece W, and adjust the feed speed of the workpiece W in the conveying direction C (hereinafter also referred to as the "conveying speed") by the number of rotations of the rollers.

[0024] The rollers 40a, 40b are provided with a driving means for rotating one or both of the transport roller 40a and the receiving roller 40b. The receiving roller 40a is disposed at a slight angle (for example, 1 to 5°) with respect to the transport direction C, so that the workpiece W can be transported at a constant speed in the transport direction C. The transport speed of the workpiece W by the transport roller 40a is, for example, 1 mm / s to 20 mm / s, and is controlled to be constant. The number of transport rollers 40a and receiving rollers 40b is not particularly limited as long as the interval is such that the workpiece W does not bend.

[0025] The cooling device (cooling means) has a hose for cooling the coil 50, and cools the coil 50 by supplying cooling water into the hose. This makes it possible to prevent the temperature of the coil 50 from rising excessively, thereby preventing problems such as breakage of the coil 50 and a decrease in heating efficiency.

[0026] The coil 50 (heating means) is, for example, one or more solenoid coils with a spirally wound conductor, and is arranged to surround the outer periphery of the workpiece W moving in the conveying direction C. Both ends of the coil 50 are electrically connected to an adjustable high-frequency power supply 20, and the coil 50 is heated by high-frequency current supplied from the high-frequency power supply 20. Therefore, the induction heating device 1 is configured such that the workpiece W is heated by the heat generated by the coil 50 when the workpiece W passes through the spiral coil 50. The coil 50 is also configured to be movable in the same direction as the conveying direction C of the workpiece W and in the opposite direction. Specifically, the coil 50 is equipped with a driving means for moving the coil 50 in the conveying direction C of the workpiece W and in the opposite direction. The control unit 10b is connected to the driving means to control the movement of the coil 50. The moving speed of the coil 50 is slower than the conveying speed of the workpiece W, and the relationship "conveying speed of the workpiece W > moving speed of the coil 50" holds.

[0027] [First action] Next, the operation of the induction heating device 1 described above, in particular the control operation by the control unit 10b, will be described. Two types of operation will be described below, and first, the operation of controlling heating based on the temperature of the workpiece W will be described.

[0028] First, as a basic operation of the induction heating device 1, the rollers 40a, 40b are rotated under the control of the control unit 10b, and power is supplied from the high-frequency power supply 20 to the coil 50. As a result, as shown in Fig. 1, the rollers 40a, 40b transport the workpiece W in the transport direction C, which is the longitudinal direction, and the workpiece W is induction heated at the heating location, which is the position of the coil 50. The rollers 40a, 40b are controlled to rotate at a constant transport speed.

[0029] During the above-described operation of the induction heating device 1, the control unit 10b shown in FIG. 2 performs the following process. First, the acquisition unit 10ba (detection means) acquires the surface temperature of the workpiece W at the heating location, which is the value detected by the temperature sensor 30a (step S1 in FIG. 3), and passes it to the determination unit 10bb. Then, the determination unit 10bb acquires the target temperature (set value) stored in the target value storage unit 10aa and compares the surface temperature of the workpiece W with the target temperature. The target temperature is the value of the surface temperature of the workpiece W that should be targeted during the heating process, and is, for example, a temperature set by experiment or calculation, and is stored in advance in the target value storage unit 10aa. As an example, the target temperature is a temperature above which the workpiece W may become overheated, and a temperature below which the workpiece W may become underheated.

[0030] The determination unit 10bb calculates the difference between the surface temperature of the workpiece W detected by the temperature sensor 30a and the target temperature (step S2 in FIG. 3). Then, the determination unit 10bb determines whether or not to control the movement of the coil 50 depending on the difference between the surface temperature of the workpiece W and the target temperature (step S3 in FIG. 3). Specifically, if there is a difference between the surface temperature of the workpiece W and the target temperature (Yes in step S3 in FIG. 3), the determination unit 10bb controls the movement of the coil 50. On the other hand, if there is no difference between the surface temperature of the workpiece W and the target temperature (No in step S3 in FIG. 3), the determination unit 10bb does not control the movement of the coil 50.

[0031] Then, when there is a difference between the surface temperature of the workpiece W and the target temperature, the heating control unit 10bc determines the movement direction D of the coil 50 according to the magnitude relationship between the surface temperature of the workpiece W and the target temperature (step S4 in FIG. 3). Specifically, when the surface temperature of the workpiece W is higher than the target temperature (first state), the heating control unit 10bc determines to move the coil 50 in the direction opposite to the transport direction C. That is, as shown in FIG. 4 (4-1), the movement direction D of the coil 50 is determined to be the left direction in the figure, relative to the transport direction C of the workpiece W, which is the right direction in the figure. In this way, when the surface temperature of the workpiece W is higher than the target temperature, the workpiece W may be overheated, so as described above, the coil 50 is moved in the direction opposite to the transport direction C, and the transport speed of the workpiece W relative to the coil 50 is increased.

[0032] Furthermore, the heating control unit 10bc determines the movement speed of the coil 50 in the determined movement direction D in accordance with the surface temperature of the workpiece W (step S5 in FIG. 3). For example, the heating control unit 10bc may determine the movement speed of the coil 50 to be a constant speed that is set in advance. Alternatively, the higher the surface temperature of the workpiece W is relative to the target temperature, the faster the movement speed of the coil 50 may be determined to be, thereby further increasing the transport speed of the workpiece W relative to the coil 50.

[0033] The heating control unit 10bc then controls the coil 50 to move in the movement direction D and at the movement speed determined as described above (step S6 in FIG. 3). As a result, the relative transport speed of the workpiece W with respect to the coil 50 increases in areas where the temperature of the workpiece W is determined to be higher than the target temperature. FIG. 5 shows the relationship between the temperature of the workpiece W over time, the transport speed, and the movement speed of the coil 50. In the section of FIG. 5 (5-1) where the temperature of the workpiece W is higher than the target temperature, the relative transport speed of the workpiece W with respect to the coil 50 increases, as shown in FIGS. 5 (5-2) to (5-4). This shortens the time the heating area of ​​the workpiece W is heated by the coil 50, reduces the amount of heat applied to the workpiece W, and prevents overheating. As a result, the workpiece W can be heated uniformly along its longitudinal direction, improving the overall quality of the heat-treated workpiece W. The control unit 10b controls the amount of power supplied to the coil 50 to be constant during the movement of the coil 50, so that the output from the coil 50 is constant.

[0034] Furthermore, when there is a difference between the surface temperature of the workpiece W and the target temperature (Yes in step S3 in FIG. 3), and the surface temperature of the workpiece W is lower than the target temperature (second state), the heating control unit 10bc determines to move the coil 50 in the same direction as the transport direction C (step S4 in FIG. 3). That is, as shown in FIG. 4 (4-2), it determines to move the movement direction D of the coil 50 to the right in the figure, relative to the transport direction C of the workpiece W, which is the right direction in the figure. In this way, when the surface temperature of the workpiece W is lower than the target temperature, the workpiece W may be insufficiently heated, so the coil 50 is moved in the same direction as the transport direction C as described above, and the transport speed of the workpiece W relative to the coil 50 is reduced.

[0035] Furthermore, the heating control unit 10bc determines the movement speed of the coil 50 in the determined movement direction D in accordance with the surface temperature of the workpiece W (step S5 in FIG. 3). For example, the heating control unit 10bc may determine the movement speed of the coil 50 to be a constant speed that is set in advance. Alternatively, the lower the surface temperature of the workpiece W is relative to the target temperature, the faster the movement speed of the coil 50 may be determined to be, and thereby the relative transport speed of the workpiece W with respect to the coil 50 may be further reduced.

[0036] The heating control unit 10bc then controls the coil 50 to move in the movement direction D and at the movement speed determined as described above (step S6 in FIG. 3). As a result, the relative transport speed of the workpiece W with respect to the coil 50 is reduced in areas where the temperature of the workpiece W is determined to be lower than the target temperature. That is, in the section shown in FIG. 5 (5-1) where the temperature of the workpiece W is lower than the target temperature, the relative movement speed of the workpiece W and the coil 50 is reduced as shown in FIGS. 5 (5-2) to (5-4). This lengthens the time that the heating area of ​​the workpiece W is heated by the coil 50, increasing the amount of heat applied to the workpiece W and preventing insufficient heating. As a result, the workpiece W can be heated uniformly along its longitudinal direction, improving the overall quality of the heat-treated workpiece W. The control unit 10b controls the amount of power supplied to the coil 50 to be constant during the movement of the coil 50, so that the output from the coil 50 is constant.

[0037] The above-described process is repeated until heating of the workpiece W is completed (step S7 in FIG. 3). For example, the control unit 10b detects the temperature of the workpiece W at regular time intervals, and controls the movement of the coil 50 in accordance with the detected temperature to heat the workpiece W.

[0038] Here, the target temperature described above may be a value within a predetermined range. As an example, the target temperature may be set to an upper limit temperature and a lower limit temperature. In this case, when the temperature of the workpiece W is higher than the upper limit temperature of the target temperature, the coil 50 may be moved in the direction opposite to the conveying direction C as described above, and the conveying speed of the workpiece W relative to the coil 50 may be controlled to increase. Also, when the temperature of the workpiece W is lower than the lower limit temperature of the target temperature, the coil 50 may be moved in the same direction as the conveying direction C as described above, and the conveying speed of the workpiece W relative to the coil 50 may be controlled to decrease. Then, when the temperature of the workpiece W is within the range of the target temperature, the coil 50 may not be moved.

[0039] [Second action] Next, a second operation of the induction heating device 1 described above, in particular, a second control operation by the control unit 10b will be described. Here, an operation for controlling heating based on the diameter of the workpiece W will be described.

[0040] First, as a basic operation of the induction heating device 1, the rollers 40a, 40b are rotated under the control of the control unit 10b, and power is supplied from the high-frequency power supply 20 to the coil 50. As a result, as shown in Fig. 1, the rollers 40a, 40b transport the workpiece W in the transport direction C, which is the longitudinal direction, and the workpiece W is induction heated at the heating location, which is the position of the coil 50. The rollers 40a, 40b are controlled to rotate at a constant transport speed.

[0041] During the above-described operation of the induction heating device 1, the control unit 10b shown in Fig. 2 performs the following process. First, the acquisition unit 10ba (detection means) acquires the diameter of the workpiece W at the heating location, which is the value detected by the laser sensor 30b (step S11 in Fig. 6), and passes it to the determination unit 10bb. At this time, the acquisition unit 10ba stores the acquired diameter of the workpiece W in the memory unit 10a.

[0042] Then, the determination unit 10bb acquires the diameter of the workpiece W previously detected by the laser sensor 30b, which is stored in the memory unit 10a, particularly the diameter of the workpiece W detected during the previous detection. The determination unit 10bb compares the diameter of the workpiece W acquired during this detection with the diameter of the workpiece W acquired during the previous detection.

[0043] The determination unit 10bb calculates the difference between the diameter of the workpiece W detected in this detection and the diameter of the workpiece W detected in the previous detection (step S12 in FIG. 6). Then, the determination unit 10bb determines whether or not to control the movement of the coil 50 depending on the difference between the diameter of the workpiece W in this detection and the diameter of the workpiece W in the previous detection (step S13 in FIG. 6). Specifically, if there is a difference between the diameter of the workpiece W in this detection and the diameter of the workpiece W in the previous detection (Yes in step S13 in FIG. 6), the determination unit 10bb determines to control the movement of the coil 50. On the other hand, if there is no difference between the diameter of the workpiece W in this detection and the diameter of the workpiece W in the previous detection (No in step S13 in FIG. 6), the determination unit 10bb determines not to control the movement of the coil 50.

[0044] Then, when there is a difference between the diameter of the current workpiece W and the diameter of the previous workpiece W, the heating control unit 10bc determines the movement direction D of the coil 50 according to the relative size of the diameter of the current workpiece W and the diameter of the previous workpiece W (step S14 in FIG. 6). Specifically, when the diameter of the current workpiece W is smaller than the diameter of the previous workpiece W (first state), the heating control unit 10bc determines to move the coil 50 in the direction opposite to the conveyance direction C. That is, as shown in FIG. 7 (7-1), the heating control unit 10bc determines to move the movement direction D of the coil 50 leftward in the drawing, relative to the conveyance direction C of the workpiece W, which is rightward in the drawing. In this way, when the diameter of the current workpiece W is smaller than the diameter of the previous workpiece W, there is a risk of the workpiece W being overheated, so the coil 50 is moved in the direction opposite to the conveyance direction C as described above, and the conveyance speed of the workpiece W relative to the coil 50 is increased.

[0045] Furthermore, the heating control unit 10bc determines the movement speed of the coil 50 in the determined movement direction D according to the diameter of the current workpiece W (step S15 in FIG. 6). For example, the heating control unit 10bc may determine the movement speed of the coil 50 to be a constant speed that is set in advance. Alternatively, the smaller the diameter of the current workpiece W is relative to the diameter of the previous workpiece W, the faster the movement speed of the coil 50 may be determined to be, thereby further increasing the transport speed of the workpiece W relative to the coil 50.

[0046] The heating control unit 10bc then controls the coil 50 to move in the movement direction D and at the movement speed determined as described above (step S16 in FIG. 6). As a result, the relative movement speed of the workpiece W with respect to the coil 50 increases in the area where it is determined that the diameter of the workpiece W will decrease. FIG. 8 shows the relationship between the temperature of the workpiece W over time and the transport speed and the movement speed of the coil 50. In the high section shown in FIG. 8 (8-1) where the diameter of the current workpiece W is smaller than the diameter of the previous workpiece W, the relative transport speed of the workpiece W with respect to the coil 50 increases, as shown in FIGS. 8 (8-2) to (8-4). This shortens the time that the heating area of ​​the workpiece W is heated by the coil 50, reduces the amount of heat applied to the workpiece W, and prevents overheating. As a result, the workpiece W can be heated uniformly along its longitudinal direction, improving the overall quality of the heat-treated workpiece W. It should be noted that while the coil 50 is moving, the control unit 10b controls the amount of power supplied to the coil 50 to be constant, and the output from the coil 50 is constant.

[0047] Furthermore, when there is a difference between the diameter of the current workpiece W and the diameter of the previous workpiece W (Yes in step S13 of FIG. 6), and the diameter of the current workpiece W is larger than the diameter of the previous workpiece W (second state), the heating control unit 10bc determines to move the coil 50 in the same direction as the transport direction C (step S14 of FIG. 6). That is, as shown in FIG. 7 (7-2), it determines to move the movement direction D of the coil 50 to the right in the figure, relative to the transport direction C of the workpiece W, which is the right direction in the figure. In this way, when the diameter of the current workpiece W is larger than the diameter of the previous workpiece W, there is a risk that the workpiece W will be insufficiently heated, so the coil 50 is moved in the same direction as the transport direction C as described above, and the transport speed of the workpiece W relative to the coil 50 is reduced.

[0048] Furthermore, the heating control unit 10bc determines the movement speed of the coil 50 in the determined movement direction D according to the diameter of the current workpiece W (step S15 in FIG. 6). For example, the heating control unit 10bc may determine the movement speed of the coil 50 to be a constant speed that is set in advance. Alternatively, the movement speed of the coil 50 may be determined to be faster as the diameter of the current workpiece W is larger than the diameter of the previous workpiece W, thereby further reducing the transport speed of the workpiece W relative to the coil 50.

[0049] The heating control unit 10bc then controls the coil 50 to move in the movement direction D and at the movement speed determined as described above (step S16 in FIG. 6). As a result, the relative transport speed of the workpiece W with respect to the coil 50 decreases in the area where it is determined that the diameter of the workpiece W will increase. That is, in the area shown in FIG. 8 (8-1) where the diameter of the current workpiece W is larger than the diameter of the previous workpiece W, the relative transport speed of the workpiece W with respect to the coil 50 decreases as shown in FIGS. 8 (8-2) to (8-4). This lengthens the time that the heating area of ​​the workpiece W is heated by the coil 50, increases the amount of heat applied to the workpiece W, and prevents insufficient heating. As a result, the workpiece W can be heated uniformly along its longitudinal direction, improving the overall quality of the heat-treated workpiece W. The control unit 10b controls the amount of power supplied to the coil 50 to be constant during the movement of the coil 50, so that the output from the coil 50 is constant.

[0050] The above-described process is repeated until the heating of the workpiece W is completed (step S17 in FIG. 6). For example, the control unit 10b detects the diameter of the workpiece W at regular time intervals, and controls the movement of the coil 50 in accordance with a comparison between the detected diameter and the previous diameter, thereby heating the workpiece W.

[0051] Here, the diameter of the previous workpiece W to be compared with the diameter of the current workpiece W described above may be a value within a predetermined range based on the diameter of the previous workpiece W. As an example, the diameter of the previous workpiece W to be compared may be set with an upper limit value that is a predetermined value higher than the median value of the diameter of the previous workpiece W and a lower limit value that is a predetermined value lower than the median value of the diameter of the previous workpiece W. In this case, if the diameter of the current workpiece W is smaller than the lower limit value based on the diameter of the previous workpiece W, the coil 50 may be moved in the direction opposite to the conveying direction C as described above to increase the conveying speed of the workpiece W relative to the coil 50. Furthermore, if the diameter of the current workpiece W is larger than the upper limit value based on the diameter of the previous workpiece W, the coil 50 may be moved in the same direction as the conveying direction C as described above to decrease the conveying speed of the workpiece W relative to the coil 50. Then, if the temperature of the workpiece W is within the target temperature range, the coil 50 may not be moved.

[0052] [Modification of the second operation] Next, a modified example of the second operation of the induction heating device 1 described above will be described. In this modified example, the shape memory unit 10ab of the memory unit 10a stores correspondence information on the transport speed of the workpiece W and the movement speed of the coil 50 corresponding to each shape of the workpiece W. As an example, as shown in FIG. 9, the shape memory unit 10ab stores pre-set values ​​such as the processing temperature, workpiece transport speed, and coil movement speed corresponding to each diameter value of the workpiece W. In this example, the processing temperature and workpiece transport speed are constant regardless of the diameter value of the workpiece W, and only the coil movement speed varies.

[0053] The heating control unit 10bc of the control unit 10b identifies the transport speed of the workpiece W and the movement speed of the coil 50 that correspond to the diameter of the current workpiece W based on the correspondence information shown in FIG. 9, and calculates the relative transport speed of the workpiece W with respect to the coil 50. As an example, when the diameter of the current workpiece W is 12 mm, the heating control unit 10bc refers to the correspondence information in FIG. 9, identifies the transport speed of the workpiece W as 4 mm / sec, and the movement speed of the coil 50 as 0.2 mm / sec, and calculates the relative transport speed of the workpiece W with respect to the coil 50. Then, the heating control unit 10bc controls the transport speed of the workpiece W relative to the coil 50 so that it becomes the calculated transport speed. In this case, the transport speed of the workpiece W and the movement speed of the coil 50 are controlled to become the transport speeds of the workpiece W and the coil 50 specified in the correspondence information.

[0054] [Modifications of the first and second operations] Next, modified examples of the first and second operations of the induction heating device 1 described above will be explained. In the above, the movement speed of the coil 50 is controlled when controlling the relative transport speed of the workpiece W with respect to the coil 50. In this modified example, the transport speed of the rollers 40a, 40b that transport the workpiece W is configured to be variable, and the transport speed of the rollers 40a, 40b can be controlled by the heating control unit 10bc of the control unit 10b. The heating control unit 10bc controls the relative transport speed of the workpiece W with respect to the coil 50 by controlling the transport speed of the rollers 40a, 40b and the movement speed of the coil 50, or by controlling only the transport speed of the rollers 40a, 40b. In other words, the heating control unit 10bc determines the movement direction D of the coil 50 depending on the relative size between the diameter of the current workpiece W and the diameter of the previous workpiece W, calculates the relative conveying speed of the workpiece W with respect to the coil 50, and controls the conveying speed of the rollers 40a, 40b and the moving speed of the coil 50 to achieve this relative conveying speed, or may control only the conveying speed of the rollers 40a, 40b.

[0055] <Second embodiment> Next, a second embodiment of the present disclosure will be described with reference to the drawings. Note that the drawings may be relevant to any embodiment.

[0056] [composition] 1, the induction heating device 1 of this embodiment has almost the same configuration as that of the above-described embodiment 1. However, the induction heating device 1 of this embodiment differs from that of embodiment 1 in the configuration of the control unit 10b.

[0057] Specifically, the control unit 10b of the induction heating device 1 in this embodiment acquires the diameter of the workpiece W at predetermined intervals (predetermined measurement cycles), and controls the relative transport speed of the workpiece W with respect to the coil 50, or controls the output of the coil 50, as described above, depending on the amount of change in the diameter. The functions of the control unit 10b will be described in detail below in the operation description.

[0058] [Operation] First, as a basic operation of the induction heating device 1, the rollers 40a, 40b are rotated under the control of the control unit 10b, and power is supplied from the high-frequency power supply 20 to the coil 50. As a result, as shown in Fig. 1, the rollers 40a, 40b transport the workpiece W in the transport direction C, which is the longitudinal direction, and the workpiece W is induction heated at the heating location, which is the position of the coil 50. The rollers 40a, 40b are controlled to rotate at a constant transport speed.

[0059] During the above-described operation of the induction heating device 1, the control unit 10b shown in Fig. 2 performs the following process. First, the acquisition unit 10ba (detection means) acquires the diameter of the workpiece W at the heated location, which is the value detected by the laser sensor 30b (step S21 in Fig. 10), and passes it to the determination unit 10bb. At this time, the acquisition unit 10ba stores the acquired diameter of the workpiece W in the memory unit 10a.

[0060] Then, the determination unit 10bb acquires the diameter of the workpiece W previously detected by the laser sensor 30b, which is stored in the memory unit 10a, particularly the diameter of the workpiece W detected during the previous detection. The determination unit 10bb compares the diameter of the workpiece W acquired during this detection with the diameter of the workpiece W acquired during the previous detection.

[0061] The determination unit 10bb calculates the difference between the diameter of the workpiece W obtained by the current detection and the diameter of the workpiece W obtained by the previous detection (step S22 in FIG. 10). Then, the determination unit 10bb determines whether to control the movement of the coil 50 (first control) or to control the output of the coil 50 (second control) depending on the difference between the diameter of the workpiece W of this time and the diameter of the workpiece W of the previous time. Specifically, if there is a difference between the diameter of the workpiece W of this time and the diameter of the workpiece W of the previous time (Yes in step S23 in FIG. 10), and the absolute value of this difference (amount of change (slope)) is greater than a preset threshold value (Yes in step S24 in FIG. 10), the determination unit 10bb determines to control the movement of the coil 50 (B: coil movement control). On the other hand, if the absolute value of the difference between the diameter of the workpiece W of this time and the diameter of the workpiece W of the previous time is equal to or less than a preset threshold value (No in step S24 in FIG. 10), the determination unit 10bb determines to control the output of the coil 50 (A: output control). At this time, a threshold value to be compared with the absolute value of the difference between the diameter of the current workpiece W and the diameter of the previous workpiece W is stored in advance in the memory unit 10a. The threshold value is a threshold value that is considered appropriate to vary the relative transport speed of the workpiece W with respect to the coil 50 so as to change the amount of heat applied to the workpiece W more significantly than varying the output of the coil 50, as will be described later, when the change in diameter (absolute value of the difference) exceeds this value, and is a value (set value) set by experiment or calculation. Note that, when there is no difference between the diameter of the current workpiece W and the diameter of the previous workpiece W (No in step S23 of FIG. 10), the judgment unit 10bb does not control the movement or output of the coil 50.

[0062] Then, as described above, when the absolute value of the difference between the diameter of the current workpiece W and the diameter of the previous workpiece W is equal to or less than the threshold value, the control unit 10b controls the output of the coil 50 as follows. Specifically, the heating control unit 10bc of the control unit 10b acquires the surface temperature of the workpiece W at the heating location, which is the value detected by the temperature sensor 30a, via the acquisition unit 10ba (step S31 in FIG. 11). The heating control unit 10bc then calculates the difference between the surface temperature of the workpiece W and the target value stored in the target value storage unit 10aa as described above, and determines and controls the current supplied from the high-frequency power supply 20 to the coil 50 based on this difference (steps S33 and S34 in FIG. 11). At this time, the heating control unit 10bc determines and controls the current using general PID control based on the difference between the surface temperature and the target temperature. This controls the heating of the workpiece W by the coil 50 based on the temperature difference, preventing overheating or underheating and ensuring uniform heating of the entire workpiece W.

[0063] FIG. 13 shows the relationship between the temperature of the workpiece W over time and the transport speed and the moving speed of the coil 50. In the section shown in FIG. 13 (13-1) where the absolute value of the difference between the diameter of the current workpiece W and the diameter of the previous workpiece W is below a threshold, the relative transport speed of the workpiece W with respect to the coil 50 does not change, as shown in FIGS. 13 (13-2) to (13-4). FIG. 14 also shows the relationship between the moving speed of the coil 50 over time and the diameters d1 to d3 of the workpiece W. As shown in FIG. 14 (14-2), when the diameter of the workpiece W changes between d1 and d2, the absolute value of the difference is below a threshold, so the moving speed does not change, as shown in FIG. 14 (14-1). In this way, there is no need to move the coil 50, as will be described later, and control of the heat treatment of the workpiece W is easier. In addition, in Figure 14 and Figure 15 described later, the movement speed of the coil 50 is shown to change suddenly when the control switches from movement control to output control, but this is only a schematic illustration, and in reality, the change is more or less gradual.

[0064] The heating control unit 10bc may control the output of the coil 50 in any manner. For example, the heating control unit 10bc may control the voltage or power supplied from the high-frequency power supply 20 to the coil 50.

[0065] Furthermore, as described above, when the absolute value of the difference between the diameter of the current workpiece W and the diameter of the previous workpiece W is greater than the threshold value, the control unit 10b controls the movement of the coil 50 as follows. Specifically, the heating control unit 10bc of the control unit 10b first determines the movement direction D of the coil 50 depending on the relative size between the diameter of the current workpiece W and the diameter of the previous workpiece W (step S41 in FIG. 12). For example, when the diameter of the current workpiece W is smaller than the diameter of the previous workpiece W, the heating control unit 10bc determines to move the coil 50 in the direction opposite to the conveying direction C. That is, as shown in FIG. 7 (7-1), the heating control unit 10bc determines to move the movement direction D of the coil 50 leftward in the drawing, relative to the conveying direction C of the workpiece W, which is rightward in the drawing. In this way, when the diameter of the current workpiece W is smaller than the diameter of the previous workpiece W, there is a risk of the workpiece W being overheated. Therefore, as described above, the coil 50 is moved in the direction opposite to the conveying direction C, thereby increasing the conveying speed of the workpiece W relative to the coil 50.

[0066] Furthermore, the heating control unit 10bc determines the movement speed of the coil 50 in the determined movement direction D according to the diameter of the current workpiece W (step S42 in FIG. 12). For example, the heating control unit 10bc may determine the movement speed of the coil 50 to be a constant speed that is set in advance. Alternatively, the smaller the diameter of the current workpiece W is relative to the diameter of the previous workpiece W, the faster the movement speed of the coil 50 may be determined to be, thereby further increasing the transport speed of the workpiece W relative to the coil 50.

[0067] Furthermore, the heating control unit 10bc may acquire the surface temperature of the workpiece W (step S43 in FIG. 12) and correct the movement speed of the coil 50 in accordance with the temperature. For example, the heating control unit 10bc compares the surface temperature with the target temperature, and if the surface temperature of the workpiece W matches the target temperature, no correction is made (Yes in step S44 in FIG. 12). If the surface temperature does not match (No in step S44 in FIG. 12), the heating control unit 10bc corrects the movement speed of the coil 50 in accordance with the difference between the surface temperature and the target temperature (step S45 in FIG. 12). As an example, when the coil 50 is moved in the direction opposite to the conveyance direction C of the workpiece W, if the surface temperature is higher than the target temperature, the movement speed of the coil 50 is corrected to be faster, and if the surface temperature is lower than the target temperature, the movement speed of the coil 50 is corrected to be slower. In this way, the conveyance speed of the workpiece W relative to the coil 50 is corrected in accordance with the surface temperature of the workpiece W. Note that the above-described method of correcting the movement speed of the coil 50 is just an example, and any method may be used for correction.

[0068] The heating control unit 10bc then controls the coil 50 to move in the movement direction D and at the movement speed determined as described above (step S46 in FIG. 12). As a result, the relative movement speed of the workpiece W with respect to the coil 50 increases in areas where it is determined that the amount of change in the diameter of the workpiece W is large (greater than the threshold value). FIG. 13 shows the relationship between the temperature of the workpiece W over time, the transport speed, and the movement speed of the coil 50. In the section shown in FIG. 13 (13-1) where the absolute value of the diameter of the current workpiece W and the diameter of the previous workpiece W is greater than the threshold value, the relative transport speed of the workpiece W with respect to the coil 50 increases, as shown in FIGS. 13 (13-2) to (13-4). This shortens the time that the heating area of ​​the workpiece W is heated by the coil 50, reduces the amount of heat applied to the workpiece W, and prevents overheating. As a result, the workpiece W can be heated uniformly along its longitudinal direction, improving the overall quality of the heat-treated workpiece W. It should be noted that while the coil 50 is moving, the control unit 10b controls the amount of power supplied to the coil 50 to be constant, and the output from the coil 50 is constant.

[0069] In the example of Fig. 14 showing the relationship between the movement speed of the coil 50 over time and the diameters d1 to d3 of the workpiece W, when the diameter of the workpiece W changes between d2 and d3 as shown in Fig. 14 (14-2), the absolute value of the difference is greater than the threshold value, and therefore the movement speed of the coil 50 is controlled to change as shown by the solid line in Fig. 14 (14-1). At this time, if the surface temperature is higher or lower than the target temperature, the movement speed can be corrected as shown by the dotted line.

[0070] Furthermore, when the absolute value of the difference between the diameter of the current workpiece W and the diameter of the previous workpiece W is greater than the threshold value, and when the diameter of the current workpiece W is greater than the diameter of the previous workpiece W, the heating control unit 10bc determines to move the coil 50 in the transport direction C (step S41 in FIG. 12). That is, as shown in FIG. 7 (7-2), it determines to move the movement direction D of the coil 50 to the right in the figure, relative to the transport direction C of the workpiece W, which is the right direction in the figure. In this way, when the diameter of the current workpiece W is larger than the diameter of the previous workpiece W, there is a risk that the workpiece W will be insufficiently heated, so as described above, the coil 50 is moved in the same direction as the transport direction C, and the transport speed of the workpiece W relative to the coil 50 is reduced.

[0071] Then, the heating control unit 10bc determines the movement speed of the coil 50 in the determined movement direction D according to the diameter of the current workpiece W (step S42 in FIG. 12). For example, the heating control unit 10bc may determine the movement speed of the coil 50 to be a constant speed that is set in advance. Alternatively, the movement speed of the coil 50 may be determined to be faster as the diameter of the current workpiece W is larger than the diameter of the previous workpiece W, thereby further reducing the transport speed of the workpiece W relative to the coil 50.

[0072] Furthermore, the heating control unit 10bc may acquire the surface temperature of the workpiece W (step S43 in FIG. 12) and correct the movement speed of the coil 50 in accordance with the temperature. For example, the heating control unit 10bc compares the surface temperature with the target temperature, and if the surface temperature of the workpiece W matches the target temperature, no correction is made (Yes in step S44 in FIG. 12). If the surface temperature does not match (No in step S44 in FIG. 12), the heating control unit 10bc corrects the movement speed of the coil 50 in accordance with the difference between the surface temperature and the target temperature (step S45 in FIG. 12). As an example, when the coil 50 is moved in the same direction as the conveyance direction C of the workpiece W, if the surface temperature is higher than the target temperature, the movement speed of the coil 50 is corrected to be slower, and if the surface temperature is lower than the target temperature, the movement speed of the coil 50 is corrected to be faster. In this way, the conveyance speed of the workpiece W relative to the coil 50 is corrected in accordance with the surface temperature of the workpiece W. Note that the above-described method of correcting the movement speed of the coil 50 is just an example, and any method may be used for correction.

[0073] The heating control unit 10bc then controls the coil 50 to move in the movement direction D and at the movement speed determined as described above (step S46 in FIG. 12). As a result, the relative movement speed of the workpiece W with respect to the coil 50 is reduced in areas where it is determined that the amount of change in the diameter of the workpiece W is large (greater than the threshold value). This lengthens the time that the heating area of ​​the workpiece W is heated by the coil 50, increases the amount of heat applied to the workpiece W, and prevents insufficient heating. As a result, the workpiece W can be heated uniformly along its longitudinal direction, improving the overall quality of the heat-treated workpiece W. Note that the control unit 10b controls the amount of power supplied to the coil 50 to be constant while the coil 50 is moving, and the output from the coil 50 is constant.

[0074] The above-described process is repeated until the heating of the workpiece W is completed (step S25 in FIG. 10). For example, the control unit 10b detects the diameter of the workpiece W at regular time intervals, and controls the movement of the coil 50 in accordance with a comparison between the detected diameter and the previous diameter, thereby heating the workpiece W.

[0075] Here, as shown in FIG. 15 (15-2), in a section where the diameter of the workpiece W changes between d2 and d3 and the amount of change (absolute value) is greater than a threshold, the heating control unit 10bc may, in addition to controlling the movement of the coil 50 as described above, perform output control to control the current supplied from the high-frequency power supply 20 to the coil 50, as shown in FIG. 15 (15-1). For example, the heating control unit 10bc may control the movement direction D and movement speed of the coil 50 to increase or decrease the transport speed of the workpiece W relative to the coil 50 in accordance with the amount of change in the diameter of the workpiece W, and may also control the output to increase or decrease the current supplied to the coil 50, thereby controlling to heat the entire workpiece W uniformly. Furthermore, at this time, in addition to controlling the movement of the coil 50 in accordance with the amount of change in the diameter of the workpiece W as described above, the heating control unit 10bc may measure the surface temperature of the workpiece W and, in accordance with the difference between the surface temperature of the workpiece W and the target temperature, control to heat the entire workpiece W uniformly. As an example, in addition to controlling the movement of the coil 50 in accordance with the amount of change in the diameter of the workpiece W as described above, when the surface temperature of the workpiece W is higher than the target temperature, the current supplied to the coil 50 is reduced to reduce the amount of heating, and when the surface temperature of the workpiece W is lower than the target temperature, the current supplied to the coil 50 is increased to increase the amount of heating. In this way, by controlling the movement of the coil 50 in accordance with the diameter and surface temperature of the workpiece W, the relative transport speed of the workpiece W with respect to the coil 50 is controlled, and by controlling the output of the coil 50, i.e., the amount of heating, the entire workpiece W can be heated uniformly and quickly.

[0076] The threshold value to be compared with the absolute value of the difference between the diameter of the current workpiece W and the diameter of the previous workpiece W may be a value having a predetermined range. As an example, the threshold value may be set to have an upper limit value and a lower limit value that is smaller than the upper limit value. In this case, when the absolute value of the difference in the diameters of the workpieces W is larger than the upper limit value, the movement control of the coil 50 may be performed as described above, and when the absolute value is smaller than the lower limit value, the output control of the coil 50 may be performed as described above.

[0077] In the above description, when controlling the movement of the coil 50, the movement speed of the coil 50 is corrected if the surface temperature of the workpiece W does not match the target temperature, but the target temperature may be a value within a predetermined range. In this case, the movement speed of the coil 50 may be corrected if the surface temperature of the workpiece W is outside the range of the target temperature.

[0078] In the above description, the coil 50 is controlled to move when the absolute value of the difference between the diameters of the workpiece W at this time and the previous time is greater than a threshold value, and the output of the coil 50 is controlled when the absolute value is equal to or less than the threshold value, but the control may be performed in the opposite manner. In other words, when the absolute value of the difference between the diameters of the workpiece W at this time and the previous time is greater than a threshold value, the output of the coil 50 may be controlled as described above, and when the absolute value is equal to or less than the threshold value, the coil 50 may be controlled to move as described above.

[0079] [Modification of operation] Next, a modified example of the operation of the induction heating device 1 described above will be described. In this modified example, the shape memory unit 10ab of the memory unit 10a stores correspondence information on the transport speed of the workpiece W and the movement speed of the coil 50 corresponding to each shape of the workpiece W. As an example, as shown in FIG. 9, the shape memory unit 10ab stores pre-set values ​​such as the processing temperature, workpiece transport speed, and coil movement speed corresponding to each diameter value of the workpiece W. In this example, the processing temperature and workpiece transport speed are constant regardless of the diameter value of the workpiece W, and only the coil movement speed varies.

[0080] The heating control unit 10bc of the control unit 10b identifies the transport speed of the workpiece W and the movement speed of the coil 50 that correspond to the diameter of the current workpiece W based on the correspondence information shown in FIG. 9, and calculates the relative transport speed of the workpiece W with respect to the coil 50. As an example, when the diameter of the current workpiece W is 12 mm, the heating control unit 10bc refers to the correspondence information in FIG. 9, identifies the transport speed of the workpiece W as 4 mm / sec, and the movement speed of the coil 50 as 0.2 mm / sec, and calculates the relative transport speed of the workpiece W with respect to the coil 50. Then, the heating control unit 10bc controls the transport speed of the workpiece W relative to the coil 50 so that it becomes the calculated transport speed. In this case, the transport speed of the workpiece W and the movement speed of the coil 50 are controlled to become the transport speeds of the workpiece W and the coil 50 specified in the correspondence information.

[0081] In addition, in the above, when controlling the relative conveying speed of the workpiece W with respect to the coil 50, the moving speed of the coil 50 is controlled, but the conveying speed of the rollers 40a, 40b that convey the workpiece W is configured to be variable, and the conveying speed of the rollers 40a, 40b may be controlled by the heating control unit 10bc of the control unit 10b.

[0082] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-described embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each of the above-described embodiments can be combined with other embodiments as appropriate.

[0083] The above-described program can be stored and supplied to a computer using various types of non-transitory computer-readable media. Non-transitory computer-readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (e.g., flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (e.g., magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, and semiconductor memories (e.g., mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash ROMs, and RAMs (Random Access Memory)). The program may also be supplied to a computer by various types of transitory computer-readable media. Examples of transitory computer-readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer-readable media can supply the program to a computer via a wired communication path such as an electric wire or optical fiber, or via a wireless communication path.

[0084] <Additional Notes> Some or all of the above embodiments can also be described as follows: The following provides an overview of the configurations of the induction heating device, control method, and program according to the present disclosure. However, the present disclosure is not limited to the configurations described in the following supplementary notes. Note that the configurations described in Appendices A2 to A6, which are dependent on Appendix A1 below, and some or all of the functions of these configurations, may also be dependent on other Appendices A7 and A8 in the same dependency relationship as Appendix A2 to A6. Furthermore, the configurations described in Appendices B2 to B9, which are dependent on Appendix B1 below, and some or all of the functions of these configurations may also be dependent on other Appendices B10 and B11 in the same dependency relationship as Appendix B2 to B9. Furthermore, any of the configurations in the following Appendices can be combined in any manner. That is, the configuration described in Appendix An (n is any number) and the configuration described in Appendix Bn (n is any number) may be combined in any manner. (Appendix A1) a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; a detection means for detecting a state of the heated portion of the member; a control means for controlling a relative transport speed of the member with respect to the heating means based on the detection result of the state of the member; Equipped with the heating means is movable in the conveying direction and in a direction opposite to the conveying direction, the control means controls the moving speed of the heating means based on the detection result of the state of the member, thereby controlling the transport speed of the member relative to the heating means. Induction heating device. (Appendix A2) An induction heating device according to appendix A1, the control means determines whether the heated portion of the member is in a preset first state based on the detection result of the state of the member, and if the heated portion is in the first state, controls the heating means to increase the moving speed in the direction opposite to the conveying direction, thereby controlling the conveying speed of the member relative to the heating means. Induction heating device. (Appendix A3) An induction heating device according to appendix A2, the control means determines whether the heated portion of the member is in a preset second state based on the detection result of the state of the member, and if the heated portion is in the second state, controls the heating means to increase the moving speed in the conveying direction and controls the conveying speed of the member relative to the heating means to decrease. Induction heating device. (Appendix A4) An induction heating device according to appendix A3, the detecting means detects the temperature at the heated portion of the member as the state; The control means determines that the first state exists when the detected temperature is higher than a preset value, and determines that the second state exists when the detected temperature is lower than a preset value. Induction heating device. (Appendix A5) An induction heating device according to appendix A3, the detecting means detects the diameter of the heated portion of the member as the state; The control means determines that the first state exists when the detected diameter is smaller than the diameter detected previously, and determines that the second state exists when the detected diameter is larger than the diameter detected previously. Induction heating device. (Appendix A6) An induction heating device according to appendix A1, the detecting means detects the diameter of the heated portion of the member as the state; the control means calculates and controls a relative conveying speed with respect to the heating means at a heating point of the member corresponding to the detected diameter based on predetermined correspondence information between the diameter of the member, the conveying speed, and the moving speed of the heating means. Induction heating device. (Appendix A7) a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; It is equipped with A control method for an induction heating device configured so that the heating means is movable in the conveying direction and a direction opposite to the conveying direction, Detecting a condition at a heated point of the member; controlling a moving speed of the heating means based on the detection result of the state of the member, thereby controlling a transport speed of the member relative to the heating means; Control method. (Appendix A8) a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; Equipped with a control device for controlling an induction heating device configured so that the heating means is movable in the conveying direction and in a direction opposite to the conveying direction; Detecting a condition at a heated point of the member; controlling a moving speed of the heating means based on the detection result of the state of the member, thereby controlling a transport speed of the member relative to the heating means; A program that executes a process. (Appendix B1) a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; a detection means for detecting a state of the heated portion of the member; a control means for performing a first control for controlling a relative transport speed of the member with respect to the heating means or a second control for controlling an output of the heating means based on the detection result of the state of the member; Equipped with the heating means is movable in the conveying direction and in a direction opposite to the conveying direction, the control means controls a moving speed of the heating means as the first control, thereby controlling a transport speed of the heating portion of the member relative to the heating means; Induction heating device. (Appendix B2) An induction heating device according to appendix B1, the detecting means detects the diameter of the heated portion of the member as the state; the control means performs the first control or the second control depending on the absolute value of the difference between the detected diameter and a previously detected diameter. Induction heating device. (Appendix B3) An induction heating device according to appendix B2, When the absolute value is greater than a preset value and the detected diameter is smaller than a diameter detected in the past, the control means performs the first control by controlling to increase the moving speed of the heating means in the direction opposite to the conveying direction, thereby controlling to increase the conveying speed of the member relative to the heating means. Induction heating device. (Appendix B4) An induction heating device according to appendix B2, When the absolute value is greater than a preset value and the detected diameter is greater than a diameter detected in the past, the control means performs the first control by controlling the heating means to increase the moving speed in the conveying direction and controlling the conveying speed of the member relative to the heating means to decrease. Induction heating device. (Appendix B5) An induction heating device according to appendix B2, When the absolute value is greater than a preset value, the control means controls the relative transport speed of the member with respect to the heating means and controls the output of the heating means to change, as the first control. Induction heating device. (Appendix B6) An induction heating device according to appendix B2, The detecting means further detects the temperature at the heated portion of the member as the state, the control means controls the relative conveying speed in the first control in accordance with the detected temperature. Induction heating device. (Appendix B7) An induction heating device according to appendix B2, When the absolute value is equal to or less than a preset value, the control means performs the second control such that the output of the heating means is changed. Induction heating device. (Appendix B8) An induction heating device according to appendix B7, The detecting means further detects the temperature at the heated portion of the member as the state, the control means controls the output of the heating means in the second control in accordance with the detected temperature. Induction heating device. (Appendix B9) An induction heating device according to appendix B1, the detecting means detects the diameter of the heated portion of the member as the state; the control means calculates and controls the relative conveying speed in the first control corresponding to the detected diameter based on preset correspondence information between the diameter of the member, the conveying speed, and the moving speed of the heating means. Induction heating device. (Appendix B10) a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; It is equipped with A control method for an induction heating device configured so that the heating means is movable in the conveying direction and a direction opposite to the conveying direction, Detecting a condition at a heated point of the member; a first control for controlling a transport speed of the member relative to the heating means or a second control for controlling an output of the heating means based on the detection result of the state of the member, and as the first control, a moving speed of the heating means is controlled to control a transport speed of the member at a heated portion relative to the heating means; Control method. (Appendix B11) a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; a control device for controlling an induction heating device configured so that the heating means is movable in the conveying direction and in a direction opposite to the conveying direction, Detecting a condition at a heated point of the member; a first control for controlling a transport speed of the member relative to the heating means or a second control for controlling an output of the heating means based on the detection result of the state of the member, and as the first control, a moving speed of the heating means is controlled to control a transport speed of the member at a heated portion relative to the heating means; A program that executes a process. [Explanation of symbols]

[0085] 1 Induction heating device 10 PLC 10a Storage section 10aa Target value storage section 10ab shape memory section 10b Control section 10ba acquisition department 10bb Judgment part 10bc Heating control unit 20 High frequency power supply 30 sensors 30a temperature sensor 30b Laser sensor 40a, 40b Roller 50 coils double work

Claims

1. a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; a detection means for detecting a state of the heated portion of the member; a control means for performing a first control for controlling a relative transport speed of the member with respect to the heating means or a second control for controlling an output of the heating means based on the detection result of the state of the member; Equipped with the heating means is movable in the conveying direction and in a direction opposite to the conveying direction, the control means controls a moving speed of the heating means as the first control, thereby controlling a transport speed of the heating portion of the member relative to the heating means; Induction heating device.

2. 2. The induction heating device according to claim 1, the detecting means detects the diameter of the heated portion of the member as the state; the control means performs the first control or the second control depending on the absolute value of the difference between the detected diameter and a previously detected diameter. Induction heating device.

3. 3. The induction heating device according to claim 2, When the absolute value is greater than a preset value and the detected diameter is smaller than a diameter detected in the past, the control means performs the first control by controlling to increase the moving speed of the heating means in the direction opposite to the conveying direction, thereby controlling to increase the conveying speed of the member relative to the heating means. Induction heating device.

4. 3. The induction heating device according to claim 2, When the absolute value is greater than a preset value and the detected diameter is greater than a diameter detected in the past, the control means performs the first control by controlling the heating means to increase the moving speed in the conveying direction and controlling the conveying speed of the member relative to the heating means to decrease. Induction heating device.

5. 3. The induction heating device according to claim 2, When the absolute value is greater than a preset value, the control means controls the relative transport speed of the member with respect to the heating means and controls the output of the heating means to change, as the first control. Induction heating device.

6. 3. The induction heating device according to claim 2, The detecting means further detects the temperature at the heated portion of the member as the state, the control means controls the relative conveying speed in the first control in accordance with the detected temperature. Induction heating device.

7. 3. The induction heating device according to claim 2, When the absolute value is equal to or less than a preset value, the control means performs the second control such that the output of the heating means is changed. Induction heating device.

8. 8. The induction heating device according to claim 7, The detecting means further detects the temperature at the heated portion of the member as the state, the control means controls the output of the heating means in the second control in accordance with the detected temperature. Induction heating device.

9. 2. The induction heating device according to claim 1, the detecting means detects the diameter of the heated portion of the member as the state; the control means calculates and controls the relative conveying speed in the first control corresponding to the detected diameter based on preset correspondence information between the diameter of the member, the conveying speed, and the moving speed of the heating means. Induction heating device.

10. a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; It is equipped with A control method for an induction heating device configured so that the heating means is movable in the conveying direction and a direction opposite to the conveying direction, Detecting a condition at a heated point of the member; a first control for controlling a transport speed of the member relative to the heating means or a second control for controlling an output of the heating means based on the detection result of the state of the member, and as the first control, a moving speed of the heating means is controlled to control a transport speed of the member at a heated portion relative to the heating means; Control method.

11. a conveying means for conveying a member having a predetermined length in a set conveying direction along the longitudinal direction; a heating means for induction heating a part of the member during transportation; a control device for controlling an induction heating device configured so that the heating means is movable in the conveying direction and in a direction opposite to the conveying direction, Detecting a condition at a heated point of the member; a first control for controlling a transport speed of the member relative to the heating means or a second control for controlling an output of the heating means based on the detection result of the state of the member, and as the first control, a moving speed of the heating means is controlled to control a transport speed of the member at a heated portion relative to the heating means; A program that executes a process.

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