JP2018200847A - Inductive heating welding device - Google Patents

Abstract

To provide an inductive heating welding device capable of obtaining more appropriate welding quality without complicating the device configuration, instead of a technique of deriving a heating time from the temperature of a sheet before heating.SOLUTION: An induction heating welding device for welding a specific portion of a sheet to a heat welding layer of a fixing member includes an electromagnetic heating unit 1 for induction-heating the fixing member through the specific portion, a temperature sensor for detecting the temperature of the specific portion, and a heating control unit 54 for stopping the heating of the electromagnetic heating unit 1 depending on the degree of arrival of the temperature value of the specific portion with respect to a specific temperature value necessary for welding the specific portion and the heat welding layer.SELECTED DRAWING: Figure 4

Description

  The present invention heats a sheet covering a conductive fixing member having a heat-welded layer on the surface from the front side, so that a specific portion of the sheet overlapped with the heat-welded layer is the heat-welded layer. The present invention relates to an induction heating welding apparatus that welds to an iron.

  Patent Document 1 discloses an apparatus for welding a sheet to a fixing member made of a conductive substrate and a thermoplastic resin layer. The apparatus includes a heating unit that heats the conductive substrate through the sheet by electromagnetic induction, a temperature measurement unit that measures the temperature of the sheet, and a heating time setting that sets a heating time by the heating unit according to the temperature of the sheet. Means. Then, by inductively heating the conductive substrate for the heating time set by the heating time setting means, the thermoplastic resin layer is thermally melted, and the sheet is welded to the fixing member installed at a predetermined position on the rooftop floor surface. .

  Specifically, when the heating coil as the heating means is accurately positioned on the conductive base of the fixing member, the non-contact type thermometer measures the surface temperature of the sheet and transmits the temperature to the computer of the apparatus. In a computer memory, a plurality of combinations of the sheet temperature value before heating and the optimum heating time at the sheet temperature value are recorded as a database by a prior experiment. The computer selects the heating time corresponding to the measured temperature of the sheet from the combination of the plurality of temperature values and the heating time recorded in advance, and automatically sets the heating time by the heating coil. Set. When the heating time is set, current is supplied to the heating coil for the set heating time, and induction heating of the conductive substrate is performed. Thereby, the thermoplastic resin layer of the fixing member is melted and the fixing member is welded to the sheet. When the set heating time has elapsed, the current supply to the heating coil is stopped, the induction heating is finished, the thermoplastic resin layer is solidified, and the sheet is fixed to the fixing member.

International Publication WO2013 / 108820

  In the induction heating welding apparatus according to Patent Document 1, the heating time is derived using the temperature value of the sheet surface measured before the welding operation (before heating) as an input value. However, in the induction heating control that relies only on the heating time, underheating or overheating is likely to occur depending on the work situation. In order to obtain an appropriate welding quality, it is important that the thermoplastic resin layer rises to an appropriate temperature. The temperature rise of the thermoplastic resin layer is not determined only by the temperature and heating time of the sheet before heating, but is also affected by pressing pressure, sheet specifications, the distance between the heating coil and the fixing member, and the ambient temperature. However, deriving the heating time using all such influencing factors as input values complicates the apparatus configuration and the control circuit, resulting in a high cost burden. Moreover, in the apparatus described in Patent Document 1, it can be seen that the temperature of the portion of the sheet surface located around the fixing member is measured. With such a configuration, the temperature rise of the measurement portion is increased. The possibility of not following the temperature rise of the fixing member that is actually warmed is high, and there is a risk of insufficient heating or excessive heating.

  From such a situation, instead of a technique for deriving the heating time from the temperature of the sheet before heating, there is a demand for an induction heating welding apparatus that can obtain more appropriate welding quality without complicating the apparatus configuration. Yes.

  An induction heating welding apparatus according to the present invention heats a sheet covering a conductive fixing member having a thermal welding layer on its surface from the front side, and thus a specific portion of the sheet that is overlapped with the thermal welding layer. An induction heating welding apparatus that welds the fixing member to the heat welding layer, an electromagnetic heating unit that induction-heats the fixing member over the specific portion, a temperature sensor that detects a temperature of the specific portion, the specific portion, and the heat And a heating control unit that stops heating of the electromagnetic heating unit according to the degree of the temperature value of the specific portion with respect to the specific temperature value necessary for welding with the weld layer.

  According to this configuration, after the heating by the electromagnetic heating unit is started, the temperature value of the specific portion of the sheet that is the welding target portion is acquired, and the temperature value is the specific temperature necessary for welding the specific portion and the heat-welded layer. If it is determined that the value corresponds to the value, that is, the temperature value of the specific part reaches the specific temperature value required for welding the specific part and the heat-welded layer, or is considered to reach after that If it is determined that the temperature value is, induction heating is stopped. Here, the temperature value corresponding to the specific temperature value means that even if induction heating is stopped when the temperature value is generated, the temperature of the specific portion is substantially the specific temperature value and is appropriately fixed. This is a temperature value at which the welding between the member and the sheet is realized. Thereby, the heating control based on the temperature rise actually generated in the specific portion after the induction heating is started is realized instead of the heating control based on the predetermined heating time set in advance.

  In addition, since such a device is configured to melt the heat-welded layer by heating the fixing member having conductivity, originally, it is appropriate to measure the temperature of the fixing member. Since a sheet is interposed between the sheets, the sheet temperature is actually measured. In the case of the present invention, in such a situation, in order to measure the temperature of a specific portion located immediately above the fixing member (thermal welding layer), that is, the temperature of the sheet surface that closely follows the temperature increase of the fixing member. Since it measures, possibility that the malfunctions, such as an overheating and an underheating, will arise can be made low.

  The temperature value that serves as a trigger for stopping induction heating may be a specific temperature value, but even after induction heating stops, there is a possibility that a relatively large temperature rise will occur due to residual heat, and the surface quality of the specific part may deteriorate. is there. Therefore, in such a case, the welding of the fixing member and the sheet becomes more appropriate when the induction heating is stopped before the temperature value of the specific portion reaches the specific temperature value. For this reason, in one preferred embodiment of the present invention, the heating control unit stops heating the electromagnetic heating unit before the temperature value of the specific portion reaches the specific temperature value.

  In one preferred embodiment of the present invention, the temperature sensor is provided with a rising temperature tendency calculating unit that estimates a rising tendency of temperature of the specific part based on a temperature value obtained from the temperature sensor continuously. The control unit stops heating of the electromagnetic heating unit based on the temperature rising tendency estimated by the rising temperature tendency calculating unit and the current temperature value. In this configuration, even after the heating by the electromagnetic heating unit is started, the temperature value of the specific portion is acquired over time, and the temperature increase tendency of the specific portion is estimated based on the temperature value. When the temperature increase tendency is estimated, the subsequent temperature value can be predicted from the current temperature value by using this temperature increase tendency. That is, after the heating by the electromagnetic heating unit is stopped, the heating by the electromagnetic heating unit can be stopped when it is estimated that the temperature value of the specific portion becomes the specific temperature value. Thereby, the reliability with which a fixing member, a sheet | seat, and welding become appropriate improves.

  In another preferred embodiment of the present invention, the temperature decreasing tendency of the specific part after the heating of the electromagnetic heating unit is stopped is calculated in advance, and the heating control unit The heating stop of the electromagnetic heating unit is determined based on the temperature decreasing tendency. In this configuration, when the heating is stopped when any temperature value is detected based on the calculated temperature increasing tendency and temperature decreasing tendency, the temperature of the specific part reaches the specific temperature value, and then the heating is performed. It can be estimated whether the temperature decreases without causing excess. And by performing control which stops induction heating at such a stop timing, induction heating control which avoids underheating and overheating as much as possible is realized.

  The induction heating welding apparatus according to the present invention employs heating control based on a temperature increase after induction heating, not heating control based on heating time. However, if an induction heating stop command is issued in a short time from the start of induction heating due to signal trouble or disturbance, welding failure occurs. In order to avoid this problem, in a preferred embodiment according to the present invention, a time setting unit capable of setting a minimum heating time is additionally provided, and the heating control unit within the minimum heating time includes the time setting unit. The heating stop of the electromagnetic heating unit is invalidated. In this configuration, the started induction heating does not automatically stop until the minimum heating time set by the time setting unit has elapsed. As a result, the minimum heating time is ensured, and the occurrence of poor welding due to signal trouble or disturbance is suppressed.

It is a perspective view which shows an induction heating welding apparatus. It is sectional drawing which shows typically the welding area | region of an electromagnetic heating unit and a sheet | seat, and a fixing member. It is a functional block diagram which shows the control function part of an induction heating welding apparatus. It is a functional block diagram which shows the data flow between the control function parts at the time of induction heating. It is explanatory drawing explaining calculation of the heating stop timing based on a specific temperature tendency. It is explanatory drawing explaining calculation of the heating stop timing based on a specific temperature tendency. It is explanatory drawing explaining calculation of the heating stop timing based on a specific temperature tendency. It is a functional block diagram which shows an example of an internal structure of a heating stop temperature determination part.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an induction heating welding apparatus including an electromagnetic heating unit 1 and an apparatus main body 10. The apparatus main body 10 and the electromagnetic heating unit 1 are connected by a connection cable 3 including a power line and a control line. The apparatus body 10 is a power supply control apparatus 4 having a rectangular parallelepiped casing 40. Different types of electromagnetic heating units 1 can be connected to the power supply control device 4.

  In this embodiment, as shown in FIG. 2, the sheet is a waterproof sheet 8 laid so as to cover the roof slab of the building. The electromagnetic heating unit 1, the waterproof sheet 8, and the fixing member 80 in a work state in which the waterproof sheet 8 is welded to the conductive fixing member 80 are shown in cross section in FIG. In this embodiment, the fixing member 80 is made of, for example, a circular steel plate, and is fixed to the roof slab with an anchor or the like. A planar hot melt adhesive layer made of a thermoplastic synthetic resin such as a polyester resin is formed on the upper surface of the fixing member 80 as a heat welding layer for the waterproof sheet 8. The fixing member 80 is disposed on the slab body at a large number of fixing points with predetermined intervals in the vertical and horizontal directions.

  An operation display device group 41 including various operation buttons and segment LEDs is disposed on the surface of the casing 40 of the power supply control device 4. The operation display device group 41 includes a sheet thickness setting dial 41a for setting the thickness of the waterproof sheet 8, a time setting dial 41b for setting the minimum heating time, and the like.

  The electromagnetic heating unit 1 includes a housing 11 in which the upper end of a cylindrical body having a circular cross section is closed with a top plate 12. The bottom surface is formed by a pad 13. The pad 13 is made of a cushioning material and has a function of effectively applying pressure to the waterproof sheet 8 after induction heating. A heating coil 20 is disposed on the upper surface of the pad 13. The heating coil 20 was wound to have a circular outer shape so as to correspond to the circular top surface shape of the fixing member 80 in order to inductively heat the fixing member 80 and melt the hot melt adhesive layer of the fixing member 80. It is a coil. The top plate 12 is provided with an arch-shaped grip 14. A heating SW 16 is provided on the upper surface of the grip 14 to give a start command for induction heating by the heating coil 20.

  Further, the electromagnetic heating unit 1 is provided with a temperature sensor 15 and a position detection sensor 17. As shown in FIG. 2, the temperature sensor 15 passes through the gap of the heating coil 20, passes through a through hole provided in the pad 13, and faces the outside from the bottom surface of the pad 13. Have When the electromagnetic heating unit 1 is placed on a portion of the waterproof sheet 8 (hereinafter referred to as a specific portion) positioned directly above the fixing member 80 with the waterproof sheet 8 interposed therebetween, the temperature detector of the temperature sensor 15 is the specific portion. The temperature of the specific part of the waterproof sheet 8 can be appropriately detected.

  A plurality of, preferably four, position detection sensors 17 are attached to the lower end of the side wall of the housing 11 with the detection surface facing downward. The position detection sensor 17 can detect the outer peripheral edge of the fixing member 80, and preferably a magnetic field sensor is suitable. Based on detection signals from the plurality of position detection sensors 17, it is possible to determine whether or not the electromagnetic heating unit 1 is placed immediately above the fixed member 80.

  FIG. 3 shows functional blocks showing control functions in the electromagnetic heating unit 1 and the power feeding control device 4. FIG. 4 shows the data flow between the control function units during induction heating. From the electromagnetic heating unit 1 to the power supply control device 4, a heating SW signal by the heating SW 16 instructing the start of power supply to the heating coil 20, a temperature value of a specific portion by the temperature sensor 15, and a position detection signal by the position detection sensor 17, Sent through the control line. Electric power for coil excitation from the power supply control device 4 to the heating coil 20 of the electromagnetic heating unit 1 is sent through a power line.

  The power supply control device 4 includes a power supply unit 43, a power supply unit 44, and a control unit 5. A power cable that sends AC power from a commercial power source or private power generation is connected to the power source unit 43. The power feeding unit 44 includes an inverter unit, generates an induction heating current for the electromagnetic heating unit 1 using power from the power source unit 43, and supplies the induction heating current to the heating coil 20. Power control in the power supply unit 44 is performed based on a control signal from the control unit 5.

  The control unit 5 is substantially constituted by a computer system, and its function is realized by hardware and a program. The control unit 5 includes an input / output processing unit 50 that exchanges signals with the outside. The control line of the electromagnetic heating unit 1 is connected to the input / output processing unit 50 via the unit connection unit 30. A satellite positioning module 45 composed of GPS is connected to the input / output processing unit 50. In addition, signals from the sheet thickness setting dial 41 a and the time setting dial 41 b are also sent to the control unit 5 via the input / output processing unit 50.

  In the control unit 5, a position determination unit 51, a time setting unit 52, a heating control unit 54, a power supply control unit 55, and a work recording unit 56 are provided as functional units whose functions are mainly realized by a program.

  The position determination unit 51 calculates the deviation of the electromagnetic heating unit 1 with respect to the fixed member 80 based on the position signal from the position detection sensor 17, compares the deviation with the set reference range, and deviates from the reference range. If it is, the power supply to the heating coil 20 is prohibited, and a buzzer or a lamp is driven to notify the positional deviation. The time setting unit 52 sets the minimum heating time input by the time setting dial 41b. The minimum heating time may be set not by the time setting dial 41b but by an internal process of the control unit 5. The time setting unit 52 also has a timer function, and starts measuring time with the input of the heating start command of the heating SW signal as a trigger. When the set minimum heating time has elapsed, a time-up is output. The induction heating started by the heating start command of the heating SW signal does not automatically stop until time up is output from the time setting unit 52. That is, the heating stop of the electromagnetic heating unit 1 by the heating control unit 54 is invalidated until the time-up is output. As a result, the minimum heating time is guaranteed, and the occurrence of defective welding locations is suppressed.

  The heating control unit 54 controls the timing of induction heating by the electromagnetic heating unit 1. The heating control unit 54 includes a heating start control unit 541 that commands the start of induction heating, and a heating stop control unit 542 that commands the stop of induction heating. Further, the heating control unit 54 outputs a temperature attaining flag when the temperature value acquired from the temperature sensor 15 continuously reaches a heating stop temperature at which induction heating by the heating coil 20 is stopped. 53.

The heating start control unit 541 receives a position determination result from the position determination unit 51 and receives a heating SW signal from the heating SW 16 by an ON operation (heating command) of the heating SW 16. The heating start control unit 541 receives a determination result indicating that the electromagnetic heating unit 1 is correctly placed above the fixed member 80 from the position determination unit 51 and confirms that the heating SW 16 has been turned ON. When the heating SW signal shown is received, a heating start command is output to the power supply control unit 55. The heating stop control unit 542 outputs a heating stop command to the power supply control unit 55 when receiving the temperature achievement flag output from the heating stop temperature determination unit 53 while the time setting unit 52 outputs the tie-up. .

  The power supply control unit 55 controls the power supplied to the heating coil 20 by adjusting a control signal supplied to the power supply unit 44. The power supply control unit 55 can change the power supply specification according to the specification of the waterproof sheet 8 such as the sheet thickness to be worked, the specification of the fixing member 80, and the like.

  Positioning data is input to the work recording unit 56 from the satellite positioning module 45, and power supply data (power value and power supply time) is input from the power supply control unit 55. The work recording unit 56 receives the heating SW signal indicating the start of heating, generates a heating work log including power supply data, positioning data, sheet thickness, and the like, and records it in the memory. In addition, if the antenna of the satellite positioning module 45 is provided in the electromagnetic heating unit 1, induction heating information in which the position of each heating welding point is accurate can be recorded.

  The induction heating welding apparatus according to the present invention can stop heating in a plurality of heating stop control modes. A plurality of heating stop control modes may be selected. Of course, only one specific control mode may be executed.

  In the simplest heating stop control mode, the heating stop temperature is set in advance based on the sheet specifications such as the material and sheet thickness of the waterproof sheet 8 and the specifications of the hot melt adhesive layer formed on the fixing member 80. When the temperature value sent from the temperature sensor 15 reaches the heating stop temperature, the heating stop temperature determination unit 53 gives a temperature achievement flag to the heating stop control unit 542. Thereby, a heating stop command is output from the heating stop control unit 542 to the power supply control unit 55, and the induction heating is stopped. That is, the heating stop temperature determination unit 53 functions to stop induction heating depending on the degree of arrival of the temperature value of the specific part.

  In another heating stop control mode, which is a more complicated control, the temperature rising tendency of a specific portion of the waterproof sheet 8 is estimated, and induction heating is stopped based on this temperature rising tendency. This heating stop control mode is referred to as an estimated heating stop mode, and the heating stop temperature determination unit 53 determines the temperature increasing tendency and temperature decreasing tendency of a specific portion based on the temperature value obtained from the temperature sensor 15 continuously. presume. The heating stop control unit 542 determines the timing at which induction heating should be stopped based on the temperature increase tendency estimated by the heating stop temperature determination unit 53 and the current temperature value.

  In order to determine the induction heating stop timing, a specific temperature value of a specific portion required for welding the specific portion of the waterproof sheet 8 and the fixing member 80 is set in advance. Then, after the heating by the heating coil 20 is stopped, the heating stop temperature determination unit 53 converts the temperature value of the specific part to the specific temperature value only by the residual heat, and sets the temperature value at the time of heating stop to the experimental result or statistical calculation result It can be inferred from the rules created based on it. When the temperature value at the time of heating stop is generated, it becomes induction heating stop timing, and the heating stop temperature determination unit 53 gives a temperature achievement flag to the heating stop control unit 542. Thereby, a heating stop command is output from the heating stop control unit 542 to the power supply control unit 55, and the induction heating is stopped.

  Next, with reference to the graphs of FIGS. 5, 6, and 7, the temperature rising tendency and induction heating stop timing of the specific portion described above will be described. 5, 6, and 7, the induction heating experiment in which the waterproof sheet 8 is induction-welded to the fixing member 80 is performed many times, and the experimental value group obtained in this experiment is statistically processed. Is a small part of the graph obtained by The horizontal axis represents the time from the start of heating, and the vertical axis represents the temperature value of a specific portion by the temperature sensor 15. The specific temperature value is indicated by Tz. Note that the graphs illustrated in FIGS. 5, 6, and 7 (the temperature increasing tendency and the temperature decreasing tendency of the specific portion) are greatly simplified.

  The graph shown in FIG. 5 is named a curve here. The a curve shows one temperature rising tendency classified from a number of temperature rising trends as experimental results. In the curve a, the temperature value becomes Ta1 at t1, the temperature value becomes Ta2 at t2, the temperature value becomes Ta3 at t3, the temperature value becomes Ta4 at t4, the induction heating is stopped at t4, and the specific temperature at t6. After reaching the value, the temperature value decreases. From this a curve, if the temperature value becomes Ta1 at t1, the temperature value becomes Ta2 at t2, the temperature value becomes Ta3 at t3, and the temperature value becomes Ta4 at t4, induction heating is stopped at that point. For example, it can be estimated that the specific temperature value is reached at t6. Therefore, the heating stop temperature determination unit 53 has a sufficiently higher probability that it is determined that the temperature increase curve of the induction heating that is currently performed becomes an a curve from the temperature value group that is acquired over time than the other curves. If it becomes larger, it is determined that the current induction heating conforms to the a curve, and if the temperature value acquired at t4 is substantially equal to Ta4, this time is determined as the induction heating stop timing. Then, the heating stop temperature determination unit 53 gives a temperature achievement flag to the heating stop control unit 542, and requests to stop induction heating.

  Similarly, in the graph named b curve shown in FIG. 6, when the temperature value becomes Tb1 at t1, the temperature value becomes Tb2 at t2, and the temperature value becomes Tb3 at t3, If induction heating is stopped at the time, it can be estimated that the specific temperature value is reached at t5. Therefore, the heating stop temperature determination unit 53 has a sufficiently higher probability that it is determined that the temperature increase curve of the induction heating that is currently performed will be the b curve from the temperature value group that is acquired continuously. If it becomes larger, it is determined that the current induction heating conforms to the b curve, and if the temperature value acquired at t3 is substantially equal to Tb3, this time is determined as the induction heating stop timing. Then, the heating stop temperature determination unit 53 gives a temperature achievement flag to the heating stop control unit 542, and requests to stop induction heating.

  In the graph named c curve shown in FIG. 7, if the temperature value becomes Tc1 at t1 and the temperature value becomes Tc2 at t2, then if induction heating is stopped at that time, t4 It can be estimated that a specific temperature value is sometimes obtained. Therefore, the heating stop temperature determination unit 53 has a sufficiently higher probability of determining that the temperature increase curve of the induction heating that is currently being performed becomes a c-curve from the temperature value group that is acquired continuously over the other curves. If it becomes larger, it is determined that the current induction heating conforms to the c curve, and if the temperature value acquired at t2 is substantially equal to Ta2, this time is determined as the induction heating stop timing. Then, the heating stop temperature determination unit 53 gives a temperature achievement flag to the heating stop control unit 542, and requests to stop induction heating.

  A configuration example of the heating stop temperature determination unit 53 having the above-described function is shown in FIG. The heating stop temperature determination unit 53 includes a rising temperature tendency calculation unit 531 and a heating stop timing determination unit 532. The rising temperature tendency calculation unit 531 stores a large number of curves showing various rising temperatures and decreasing temperatures in the form of a table or a database. A curve showing a temperature rising tendency similar to the temperature rising tendency in this induction heating from a combination group of temperature values acquired over time at predetermined intervals and time from heating is a condition probability method and pattern recognition. It is derived using a method. The heating stop timing determination unit 532 refers to the curve showing the temperature rising tendency derived by the rising temperature tendency calculation unit 531, and the combination of the temperature value acquired at that time and the acquisition time is the induction heating stop timing in the curve. When it is regarded as a coordinate value representing, a temperature achievement flag is output.

[Another embodiment]
(1) In the above-described embodiment, the sheet welded to the fixing member 80 is the waterproof sheet 8, but other sheets may be used.

(2) In the embodiment described above, the temperature sensor 15 is located inside the heating coil 20, but may be located slightly outside the outer periphery of the heating coil 20. That is, the specific portion of the sheet includes a region slightly outside the outer periphery of the heating coil 20 that is in contact with the sheet, and further includes a region slightly inside the outer periphery of the heating coil 20.

(3)
In the embodiment described above, the induction heating is started by the operation of the heating SW 16 by the operator, and the induction heating is automatically stopped. However, at the operator's discretion, it may be desired to stop induction heating at an early point, extend induction heating, increase induction heating intensity, or the like. An operation device for stopping induction heating may be provided to satisfy this demand.

(4)
Each functional unit of the control unit 5 shown in FIG. 3 and FIG. 4 is divided for convenience of explanation, and a plurality of arbitrary functional units may be integrated, or each functional unit may be further divided. May be.

  Note that the configurations disclosed in the above-described embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with the configurations disclosed in the other embodiments as long as no contradiction arises. The embodiment disclosed in this specification is an exemplification, and the embodiment of the present invention is not limited to this. The embodiment can be appropriately modified without departing from the object of the present invention.

  The present invention is applicable to an induction heating welding apparatus that uses induction heating to weld a sheet to a fixing member.

1: Electromagnetic heating unit 16: Heating SW
15: Temperature sensor 3: Connection cable 4: Power supply control device 5: Control unit 52: Time setting unit 53: Heating stop temperature determination unit 531: Increased temperature tendency calculation unit 532: Heating stop timing determination unit 54: Heating control unit 541: Heating start control unit 542: heating stop control unit 55: power supply control unit 80: fixing member 8: waterproof sheet 20: heating coil 41a: sheet thickness setting dial 41b: time setting dial 44: power supply unit

Claims (5)

Induction of welding a specific portion of the sheet overlapped with the thermal welding layer to the thermal welding layer by heating the sheet covering the conductive fixing member having the thermal welding layer on the surface from the front side. A heat welding device,
An electromagnetic heating unit for inductively heating the fixing member over the specific portion;
A temperature sensor for detecting the temperature of the specific part;
A heating control unit that stops heating of the electromagnetic heating unit according to the degree of the temperature value of the specific part with respect to the specific temperature value required for welding the specific part and the heat-welded layer; apparatus.   The induction heating welding apparatus according to claim 1, wherein the heating control unit stops heating of the electromagnetic heating unit before the temperature value of the specific portion reaches the specific temperature value. Based on a temperature value acquired from the temperature sensor over time, a rising temperature tendency calculating unit for estimating a rising temperature tendency of the specific part is provided,
The induction heating welding apparatus according to claim 1, wherein the heating control unit stops heating of the electromagnetic heating unit based on a temperature rising tendency estimated by the rising temperature tendency calculating unit and a current temperature value. The temperature decreasing tendency of the specific part after the heating stop of the electromagnetic heating unit is calculated in advance,
The induction heating welding apparatus according to claim 3, wherein the heating control unit determines heating stop of the electromagnetic heating unit based on the temperature increasing tendency and the temperature decreasing tendency. A time setting unit that can set the minimum heating time is provided.
The induction heating welding apparatus according to any one of claims 1 to 4, wherein heating stop of the electromagnetic heating unit by the heating control unit within the minimum heating time is invalidated.

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