JP2012219311A - Induction heating apparatus and induction heating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating apparatus and a heating method by means of which even when a workpiece is large, the entire region to be heated of the workpiece, set so as to extend in one direction of the workpiece can be readily and substantially uniformly heated to a predetermined high temperature.SOLUTION: An induction heating apparatus is provided for induction-heating a workpiece W in which the region H to be heated is set so as to extend in one direction. The induction heating apparatus include: heating coils 451 facing a part of the entire length along the one direction of the region H to be heated; a relative movement means 112 for relatively moving the workpiece W and the heating coils 451 along one direction; and a displacement means 460 for separately displacing the positions of plurality of the heating coils 451 to the width direction of the region H to be heated. The faced area between the plurality of heating coils 451 and the region H to be heated, is adjusted so as to change in the width direction of the region H to be heated, by displacing each heating coil 451 by the displacement means 460, and the region H to be heated is heated with the plurality of heating coils 451.

Description

  The present invention relates to an induction heating apparatus and an induction heating method for induction heating a work extending in one direction and having a heated region set.

  A work in which a heated region extending in one direction is set is induction heated by a heating coil. For example, when heating a large workpiece having an annular shape, the heating coil is opposed to a part of the heated region extending in one direction of the workpiece, and the entire heated region of the workpiece is heated by rotating the workpiece, for example. A heat treatment apparatus has been proposed.

  Patent Document 1 below discloses a high-frequency heat treatment apparatus capable of heating a ring-shaped workpiece such as a large bearing race. In this technique, a plurality of horseshoe-shaped heating coils are arranged at a plurality of locations in the circumferential direction of the ring-shaped workpiece, and induction heating is performed by the plurality of heating coils while rotating the ring-shaped workpiece.

  In Patent Document 2 below, an apparatus that performs high-frequency heat treatment on the entire annular component is disclosed. In this technology, the outer diameter surface or inner diameter surface of an annular component is positioned by a positioning roller, heating coils are arranged on a part of the inner circumferential surface, outer circumferential surface, side surface, etc. of the annular component, and the annular component is rotated and guided. Heating.

JP 2005-325409 A JP 2009-287074 A

  However, in the conventional heating apparatus using induction heating, it is not easy to raise the temperature of the heated region to a predetermined heating temperature when a large workpiece is quenched. In the case of a large workpiece, it is not practical because the heating coil is disposed so as to face the entire heated region because it is extremely expensive. For this reason, if heating is performed using a heating coil facing a part of the heated area, the amount of steel for the heated area is large, so heating for a long time is required and the amount of deformation due to thermal expansion of the workpiece over time is increased. It becomes large and it is difficult to maintain optimal heating conditions.

  In particular, when the deformation amount due to thermal expansion during heating is different between one side edge side and the other side edge side of the heated region continuous in one direction of the work, the work is deformed unevenly. For this reason, it is difficult for a large workpiece to raise the temperature of the entire heated region uniformly to a predetermined high temperature with a heating coil.

  Therefore, the present invention can easily raise the entire heated region set to extend in one direction to the workpiece to a predetermined high temperature even for a large workpiece, and the workpiece is not uniform during heating. An object of the present invention is to provide an induction heating apparatus and an induction heating method that can uniformly heat even if deformation occurs.

  An induction heating device of the present invention that achieves the above object is a heating device that induction-heats a workpiece that extends in one direction and has a heated region set therein, and includes a plurality of heating coils facing a part of the heated region; A relative movement means for relatively moving the workpiece and the plurality of heating coils along one direction, and a displacement means for separately displacing the position of the heating coil in the width direction of the heated region. By displacing the coil, the opposed area between the plurality of heating coils and the heated region is adjusted to change in the width direction of the heated region, and the heated region is heated by the plurality of heating coils.

  This induction heating apparatus includes power adjustment means for separately adjusting high-frequency power supplied to a plurality of heating coils, adjusts the position of each heating coil by a displacement means, and supplies high-frequency power to each heating coil by the power adjustment means. It is preferable that the heated region is heated by a plurality of heating coils.

The plurality of coils may have the same shape.
The workpiece is suitable for a workpiece in which the deformation amount differs between one side edge side and the other side edge side of the heated region when the heating region is induction-heated.

  Preferably, the displacement means is provided with an attitude control unit that controls the operation of the displacement means, and the attitude control unit adjusts the position of each heating coil corresponding to the gap between the heated region and each heating coil. Displace. The posture control unit may displace the positions of the plurality of heating coils during the heating period.

  The posture control unit calculates the arrangement of a plurality of heating coils corresponding to the gap between the heating region and the plurality of heating coils in the assumed heating state of the heated region, and a setting input unit for inputting the heating condition of the workpiece A processing unit, a heating state determination unit that determines that the heating state of the heated region has reached the assumed heating state, and a drive that drives the displacement means based on the arrangement of the plurality of heating coils when the assumed heating state is reached A control unit, and the arithmetic processing unit may calculate the gap in the assumed heating state based on the heating condition by a preset simulation process to determine the arrangement of the plurality of heating coils.

The induction heating method of the present invention is a heating method that induction-heats a workpiece that extends in one direction and has a heated region, and a heating coil is opposed to a part of the heated region, and A heating step of heating the workpiece by the heating coil while relatively moving along one direction, and by displacing the plurality of heating coils separately in the width direction of the heated region during the heating period, This is a method of adjusting so that the area facing the heating region changes in the width direction of the heated region.
In this method, it is preferable to determine the arrangement of the plurality of heating coils by calculating a gap in the assumed heating state based on the heating conditions by a preset simulation process.

  According to the heating device and the heating method of the present invention, it is provided with displacement means for separately displacing the positions of the plurality of heating coils in the width direction of the heated region, and by displacing the position of each heating coil by the displacement means, Since the arrangement distribution of the plurality of heating coils in the width direction of the heated region is adjusted, the heat generation site by induction heating can be adjusted for each heating coil. Therefore, the heat generation amount distribution in the width direction of the heated area can be adjusted, the temperature of the heated area can be prevented from becoming non-uniform in the width direction of the heated area, and the entire heated area can be substantially uniformly brought to a predetermined temperature. The temperature can be raised.

It is a fragmentary sectional view showing a work of heating object of the present invention. It is a top view of the heat processing apparatus which concerns on embodiment of this invention. It is a side view of the heat processing apparatus which concerns on embodiment of this invention, and has abbreviate | omitted and shown the heating part provided in the near side. It is sectional drawing which shows the state which connected the jig | tool of the heat processing apparatus which concerns on embodiment of this invention to the conveyance loader. It is a figure which shows the screen of the main menu in the operation part of the heat processing apparatus which concerns on embodiment of this invention. It is a figure which shows the portable terminal device in the operation part of the heat processing apparatus which concerns on embodiment of this invention. It is a schematic plan view which shows the heating section of the heat processing apparatus which concerns on embodiment of this invention. (A) is a side view of the heating part and the displacement means in the heating section of the embodiment, (b) is a rear view, and (c) is a partial plan view. It is a partial side view of the position detection part in the heating section of embodiment of this invention. (A) is the front view which shows the heating coil in the heat processing apparatus of embodiment, (b) is the partial front view which shows the shape of the part facing the workpiece | work in the heating coil of a modification, (c) is in the heating coil of a modification. It is a partial front view which shows the shape of the opposing part with a workpiece | work. It is a circuit diagram regarding the electric power feeding installation of the heat processing apparatus which concerns on embodiment of this invention. It is a figure which shows typically the step data setting screen displayed on the input / output screen of the operation part of electric power feeding equipment. It is a figure which shows typically the setting screen of the circuit setting conditions displayed following the step data setting screen shown in FIG. FIG. 12 is a diagram schematically showing the output characteristics of the inverter when induction heating is performed in a relatively short time without changing the frequency of the output from the inverter during heating in a circuit configuration different from that in FIG. 11. It is a schematic sectional drawing for demonstrating the nonuniform deformation | transformation of a workpiece | work, and has shown the deformation | transformation exaggeratingly. It is a block diagram which shows the attitude | position control part which concerns on embodiment of this invention. It is a flowchart which shows the heating process which concerns on embodiment of this invention. It is a schematic sectional drawing which shows the heating state of the workpiece | work in the heat processing apparatus which concerns on embodiment of this invention, and has shown the deformation | transformation exaggeratingly. It is an expanded view which shows arrangement | positioning of the coil in the heat processing apparatus which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
This embodiment demonstrates using the example of the turning-type hardening apparatus for heating and cooling and hardening a large annular | circular shaped heating target object.

[work]
First, the workpiece which is the heating target of the present invention will be described.
The workpiece to be heated is made of a material that can be hardened, such as a steel material, and may be heated only on the surface side or heated to the inside. An area to be heated including a surface to be heated is set to extend in a substantially constant shape in one direction. In particular, it is preferable to apply to a workpiece shape in which the entire length of the heated region H is longer than the width that is the distance between both side edges of the heated region. Here, the one direction is a direction along a straight line, a wavy line, a curved line, or the like extending between both ends in the case of a work with ends, and a direction along the ring shape in the case of an annular work.

  The shape of the workpiece is arbitrary, but when the heated region is induction-heated, it is suitable for a workpiece having a shape in which the deformation amount due to thermal expansion differs between one edge side and the other edge side in the width direction of the heated region. . For example, in the cross-sectional shape orthogonal to the heated region, when the shape is greatly different between one edge side and the other edge side of the heated region, it is due to thermal expansion when induction heating is performed on both edge sides of the heated region. The amount of deformation is different.

  As shown in FIG. 1, the workpiece W of the present embodiment has an annular shape, and includes a base W1 and a protrusion W2 protruding inward from the base W1. The protrusion W2 has an inclined surface W3 inclined in the opposite direction toward the inside, and an endless heated region H is set on the inclined surface W3. This work W is an example of an outer ring constituting a large turning wheel or a large bearing having an annular shape with a diameter of 1 m or more, here 3 m or more.

[Heat treatment equipment]
Next, the heat treatment apparatus of this embodiment will be described.
2 to 4, the heat treatment apparatus 10 includes a jig 100 that supports the workpiece W, a loading / unloading section 300 that loads and unloads the workpiece W, and a conveyance mechanism 200 that hangs and conveys the jig 100. A heating section 400 that heats the workpiece W placed on the jig 100 while rotating it, a cooling section 500 that is provided below the heating section 400, and a component that is provided on the opposite side of the loading / unloading section 300 A replacement section 600 and electrical equipment for driving each section are provided.

  As shown in FIG. 4, the jig 100 includes a work support part 110 on which the work W is placed, and a central structure part 130 provided at the center of the work support part 110. The work support unit 110 includes a rotating roller 112 as a relative movement unit disposed along the radial direction on the distal end side of a plurality of radial mounts 111 extending in the radial direction. The rotating roller 112 can be driven to rotate by a driving force input to the central structure 130. The workpiece W can move along the ring shape by rotating each rotary roller 112.

  2 and 3, the loading / unloading section 300 places the workpiece W on the workpiece support 110 of the jig 100 at the loading / unloading position P1, moves the workpiece W to the suspension position P2, and suspends the jig 100. It has a structure that can be accurately placed at the lowered position P2.

  As shown in FIGS. 2 and 3, the transport mechanism 200 includes a transport rail 210 disposed above each section, and a transport loader unit 220 that moves along the transport rail 210. As shown in FIG. 4, the transport loader 220 can be connected to the central structure 130 of the jig 100 and has a structure in which the jig 100 is suspended and transported in the connected state. The conveyance loader 220 is provided with a rotation driving means 246. When the conveyance loader 220 is connected to the central structure 130 of the jig 100, each rotation roller 112 of the jig 100 can be rotationally driven by the rotation driving means 246. It becomes.

  As shown in FIGS. 2 and 3, the heating section 400 is configured to uniformly heat the work W placed on the jig 100 while rotating the work W placed in a predetermined position. It has an applied structure. Details will be described later.

  As shown in FIG. 3, the cooling section 500 is provided below the heating section 400 and is cooled by supplying a cooling liquid from the cooling jacket 520 while rotating the workpiece W in a state where the jig 100 is lowered. It has the structure to do.

  As shown in FIGS. 2 and 3, the component replacement section 600 has a structure in which the components of the heating section 400 and the cooling section 500 are supported and conveyed by the component replacement jig 620 and the components of each section can be replaced. Yes.

  The electrical equipment is configured to be able to supply power to all sections, and is provided with an operation unit 710 for controlling and operating each operation part of all sections. The operation unit 710 is provided with a touch panel as shown in FIG. 5, and can input information for each section and monitor the operation. On the main menu of the operation unit 710, as shown in FIG. 5, a screen for inputting and displaying a monitor for each section, model selection, heating condition setting, measurement data, and parameters can be selected.

The operation unit 710 includes a portable terminal 701 that can be easily carried by an operator as shown in FIG. The portable terminal 701 can select a screen for inputting and displaying a monitor for each section, model selection, heating condition setting, measurement data, and parameters so that the same operation as the operation unit 710 can be performed. . The portable terminal 701 can be used by connecting to a connection portion provided at a plurality of positions around the heat treatment apparatus 10 via a cable 702 in a wired manner.
Here, since the connection portions are provided at a plurality of positions of the heat treatment apparatus 10, the operator can perform various inputs and operations without moving to the operation panel of the operation unit 710 at various places of the heat treatment apparatus 10. Can do. In addition, since the cable 702 is connected in a wired manner, even a device that performs heat treatment using high frequency can be operated normally with communication failure prevented.

[Overall configuration of heating section]
As shown in FIG. 7, the heating section 400 heats the workpiece W placed on the jig 100 and the jig holding mechanism 410 that supports the radiation base 111 of the jig 100 from below and restricts the movement in the circumferential direction. And a plurality of heating units 450. A plurality of jig holding mechanisms 410 and heating units 450 are provided around the rotation center C of the workpiece W that is the center of the jig 100. Here, the heating position P3 of the workpiece W is provided between the radiation bases 111 adjacent to each other of the jig 100, and each heating unit 450 is disposed so as to correspond to the heating position P3.

[Heating section]
As shown in FIGS. 7 and 8, each heating unit 450 includes a position detection unit 480 that detects the surface position of the workpiece W, and a heated region of the workpiece W placed on the jig 100 at each heating position P <b> 3. A heating coil 451 arranged opposite to H, a part of the electrical equipment, a power feeding facility 700 for controlling each part of the heating unit 450 and feeding high frequency power to the heating coil 451, and a heating coil 451 are connected. The support box 452 to be supported, the displacement means 460 for displacing and turning the support box 452 to displace the relative position of the heating coil 451 with respect to the workpiece W and changing the relative angle, and the operation of the displacement means 460 are controlled. The posture control unit 490 that adjusts the relative position and relative angle between the workpiece W and the heating coil 451 and a part of the power supply equipment 700 are provided to the heating coil 451. A power adjusting means 491 for adjusting the high-frequency power, and a.

[Position detection means]
The position detection means 480 detects the position of the workpiece surface during heating, and is arranged upstream of each heating position P3 as shown in FIG. In this embodiment, it arrange | positions in the position corresponding to the radiation stand 111 of the jig | tool 100 arrange | positioned in the upstream of every two heating positions P3.

  Specifically, each position detection means 480 is mounted on a position detection table 44 provided on the position detection column 43 of the heating / cooling frame 40 as shown in FIG. Each position detection means 480 includes a radial position detector 483 mounted on the position detection column 43 via a first advance / retract mechanism 481 and an axial position detector 484 mounted via a second advance / retract mechanism 482. Prepare. The radial position detector 483 and the axial position detector 484 are arranged in a direction orthogonal to each other.

  The first and second advancing / retracting mechanisms 481 and 482 include an advancing / retreating drive means 485 made of an air cylinder or the like, and a plurality of guide rods 487 parallel to the rods 486 of the advancing / retreating drive means 485. The forward / backward mechanisms 481 and 482 are prevented from falling along the detection direction of the position detectors 483 and 484 by the rod 486 and the guide rod 487.

  The radial position detector 483 and the axial position detector 484 are respectively a heat-resistant contact 488 that can roll while abutting on the surface of the work W, and a contact while urging the contact 488 toward the work W side. And a change amount detection unit 489 for detecting the amount of advance / retreat 488. As each change amount detection unit 489, for example, an air cylinder with a linear sensor can be used.

  Since the temperature of the heated area H becomes high during heating, the contact 488 is brought into contact with a position other than the heated area H for detection. In the radial position detector 483, the contact 488 is brought into contact with an intermediate portion of the outer peripheral surface of the workpiece W, and the surface position of the workpiece W along the radial direction from the rotation center C of the workpiece W is detected. In the axial position detector 484, the contact is brought into contact with the outer portion of the upper surface of the workpiece W placed on the jig 100, and the surface position of the workpiece along the axis of the rotation center C of the workpiece W is detected.

At the time of heating, in each position detecting means 480, the contact 488 of the radial position detector 483 and the axial position detector 484 is brought into contact with the workpiece W. When the workpiece W rotates, the contact 488 in contact with the surface moves forward and backward according to the displacement of the surface of the workpiece W while rolling. For example, the amount of displacement from the reference position at each position in the circumferential direction of the workpiece W is detected by measuring the advance / retreat amount of the contact 488 using an arbitrary position in the circumferential direction of the workpiece W as a reference position. Since the work W is an annular body, the work W returns to its original position by one rotation.
Thus, by detecting the displacement amount of the contact 488 in the change amount detection unit 489, the vertical displacement and the horizontal displacement of the surface of the workpiece W are detected, and a signal indicating the measurement position is output.

[Heating coil]
The heating coil 451 is formed to have a size that faces a part of the entire length along one direction of the heated region H, and is disposed to face a portion that is disposed at the heating position P3 in the entire circumference of the workpiece W. . The heating coils 451 of the heating units 450 are evenly arranged over the entire length of the heated region H with a predetermined interval therebetween.
The shape of the heating coil 451 can be selected as appropriate. The shape of the heating coil 451 corresponds to the arc shape of the heated portion of the workpiece W in a plan view, and has a longitudinal sectional shape corresponding to the longitudinal sectional shape of the workpiece W. Here, the plurality of heating coils 451, preferably all the heating coils 451, have the same shape.

  For example, each heating coil 451 may have a shape in which a pipe material, a bar shape, or a plate shape coil material having a substantially constant cross section is repeatedly meandered in a predetermined region in the circumferential direction of the workpiece W. Specifically, as shown in FIG. 10 (a), the square pipes are joined so that the hollow portion is continuous over the entire length, the coolant inlets 451b and the outlets 451c are provided at both ends, and the parts facing the workpiece W are The zigzag shape may be bent by a plurality of bent portions 451d. As shown in FIG. 10B, the portion facing the workpiece W may have a zigzag shape in which a pipe-shaped coil material having a round cross section is curved by a plurality of curved portions 451e.

  When the perimeter differs between the inner side and the outer side of the heated region H, the heating coil 451 may be as shown in FIG. The heating coil 451 is formed of a square pipe at a portion facing the workpiece W, and the square pipe is bent by a plurality of bent portions 451f on the inside and outside of the workpiece and bent portions 451g provided between the bent portions 451f. It may be formed in a shape. The heating coil 451 may be configured such that the circumferential length at a portion far from the rotation center C is longer than the circumferential length at a portion near the rotation center W.

In such a heating coil 451, in order to heat the heated region H more uniformly, it is desirable that the gap, which is a gap between the heating coil 451 and the heated region H, be as uniform as possible as a whole.
Therefore, it is preferable that the shape of the heated region H and the shape of the surface of the heating coil 451 that faces the heated region H match as wide as possible. Further, it is preferable that the facing area, which is the area of the surface of the heating coil 451 that faces the heated region H, be as uniform as possible in the width direction of the heated region H. Furthermore, in the cross section orthogonal to the heated region H, the angle between the surface of the heating coil 451 facing the heated region H and the heated region H should be as small as possible, and preferably 0 degrees.
The width of the heating coil 451 in the direction orthogonal to the heated region H is preferably equal to the width of the heated region H. When the width of the heating coil 451 is narrow, it can be heated uniformly by the entire width of the heated region H by shifting the arrangement of the plurality of heating coils 451 in the width direction.

  The heating coil 451 of this embodiment has a surface corresponding to the heated region H having a shape corresponding to the heated region H, and the width orthogonal to the heated region H is slightly narrower than the width of the heated region H. ing.

[Power supply equipment]
As shown in FIG. 11, the power supply facility 700 is provided for each heating coil 451 by a plurality of transformers 722, a plurality of matching units 723, an inverter 724, an inverter control unit 725, a switch group 726, and the like.
The inverter 724 includes a forward conversion unit 724A that converts the commercial voltage from the commercial power source 729 into a DC voltage, and an inverse conversion unit 724B that converts the DC voltage output from the forward conversion unit 724A into a voltage having a specified frequency. ing.
The inverter control unit 725 includes a forward conversion control unit 725A that controls the forward conversion unit 724A, and an inverse conversion control unit 725B that outputs a voltage of a specified frequency from the inverse conversion unit 724B by controlling the inverse conversion unit 724B. Prepare. A plurality of inverse conversion control units 725 </ b> B are provided, and the frequency of the power output from the inverter 724 can be changed according to the time from the start of induction heating of the workpiece W.
As the switch group 726, a switch 726D is provided for connecting one of the plurality of matching units 723 to the inverter 24, and a switch for connecting one of the plurality of matching units 723 to one of the plurality of transformers 722. 726B and 726C are provided, a switch 726A for connecting one of the plurality of transformers 722 to the heating coil 451 is provided, and a switch 726E for connecting one of the reverse conversion control units 725B to the reverse conversion unit 724B is provided. It is done.
Here, the plurality of matching units 723 are configured by capacitors having different capacities, and the plurality of transformers 722 have different numbers and turns of primary and secondary windings. Each matching unit 722 may include a coil in addition to a capacitor. The switches in the transformers 722A, 722B, 722C and the matching units 723A, 723B, 723C are for adjusting the inductances and reactances of the transformers, the matching units, and are switched by the switching control unit 727.

  The operation unit 710 uses the frequency and magnitude of the voltage output from the inverter 724 and the combination of the matching unit 723 and the transformer 722 as a circuit setting condition as the matching impedance matching the frequency with the time from the start of induction heating. It is configured to be configurable. In this way, when a predetermined time has elapsed from the start of induction heating in anticipation of changes in physical properties such as the magnetic permeability of the workpiece W due to induction heating, induction heating is temporarily stopped, and immediately thereafter, the voltage output from the inverter 724 is separated. It is possible to set the operation unit 710 so that the matching impedance matching the other frequency is replaced with a combination of the matching device 723 and the transformer 722.

  The switching control unit 727 selectively switches the switch group 726 according to the elapsed time from the start of induction heating in accordance with the circuit setting conditions set in the operation unit 710. Thereby, the combination of the matching device 723 and the transformer 722 is set as the value and frequency of the voltage output from the inverter 724 and the matching impedance.

  Specifically, for example, “heating condition setting” is selected in the main menu of the input / output screen 711 of the operation unit 710 shown in FIG. Then, for example, a step data setting screen as shown in FIG. 12 is displayed on the input / output screen 711. In this step data setting screen, power and voltage can be set as output conditions from the inverter connected to each step time, work rotation speed, and heating coil in units of steps. Also, in a specific step, the power is not supplied from any inverter, the power and voltage are set to zero as the output condition from the inverter, and switching of the matching circuit composed of the combination of the transformer 722 and the matching device 723 is performed. You can make a choice. When “switching of matching circuit” is selected, a screen as shown in FIG. 13 is displayed, and the types of the transformer 722 and the matching unit 723 can be selected. For example, as shown in FIG. 13, for each number of heating coils 451, an “MTr voltage selection” option for selecting the number of turns for selecting a transformer and an “ The “capacitor capacity” option and the inverse conversion control unit option are displayed as circuit setting conditions.

  Thus, by selecting the heating condition setting from the main menu of the input / output screen 711 in the operation unit 710, the output setting from the inverter 724 and the matching circuit can be selected in units of time from the start of induction heating. Therefore, when the switching control unit 727 receives the input of the induction heating start from the operation unit 710, the switching control unit 727 performs the sequence of the inverter control unit 725 for each elapsed time from the induction heating start according to the circuit setting condition set in the operation unit 710. The inverter 724 is controlled by the conversion control unit 725A and the selected inverse conversion control unit 725B, the voltage of the designated frequency is output from the inverter 724, and the frequency of the selected matching unit 723 and transformer 722 is the frequency. Impedance matching suitable for Therefore, even if the workpiece undergoes tissue deformation due to induction heating and changes in physical properties such as magnetic permeability, the switch group 726 is switched by the switching control unit 727 according to the circuit setting conditions set by the operation unit 710.

  According to the power supply facility 700 shown in FIG. 11, the operation unit 710 divides the induction heating time into a plurality of heating coils 451, that is, induction heating circuits, and sets the frequency of the voltage output from the inverter 724 for each division. Setting information and selection information of a matching circuit configured by a combination of a plurality of matching units 723 and a plurality of transformers 722 can be set as circuit setting conditions. Then, the switching control unit 727 selects one of the plurality of inverse conversion control units 725B for each section according to the circuit setting condition set by the operation unit 710 for each induction heating circuit, and controls the inverse conversion unit 724B. Then, a voltage having a specified frequency is output, and one matching unit 723 is connected to the inverter 724 by the switch group 726, and this one matching unit 723 is connected to one transformer 722, and this one transformer 722 is connected. Is connected to the heating coil 451. Therefore, impedance matching is restored by induction heating in response to a change in the structure of the workpiece W, an induced current can be passed through the workpiece W, and sufficient power can be supplied to a desired temperature.

  Further, when induction heating is performed while a large work W such as an outer ring constituting a large turning wheel or a large bearing having a diameter of 1 m or more is traveling, the entire induction heating time has to be long. Then, the problem that impedance is not matched and power is not supplied from the inverter 724 to the heating coil 451 due to the temperature change of the workpiece W due to the temperature rise can be solved.

  This will be specifically described below. Unlike the circuit shown in FIG. 11, it is assumed that one matching unit and one transformer are sequentially connected to the inverter, and a heating coil is connected to the transformer. That is, FIG. 14 schematically shows the output characteristics of the inverter when induction heating is performed in a relatively short time without changing the output frequency from the inverter during heating. As can be seen from FIG. 14, with a relatively small work, the temperature of the work is about 700 ° C. to 800 ° C. after the output impedance from the inverter once decreases and takes a minimum value as the induction heating time elapses. The output impedance is constant before and after. When the output impedance does not increase, the inverter output voltage peaks and then decreases. Therefore, thereafter, the output from the inverter is not input to the work.

  Therefore, as shown in FIG. 11, the switching control unit 727 changes the frequency of the output from the inverter during induction heating, and switches the combination of the matching unit 723 and the transformer 722 by the switch group 726 accordingly. For example, the induction heating time is divided into two sections, the first half of induction heating and the second half of induction heating, and matching is performed between the inverter 724 and the heating coil 451 in units of induction heating time, and the induction current having the most suitable frequency value is set as a work piece. Can flow to W. When the temperature of the workpiece W reaches 700 ° C. to 800 ° C., the structure of the workpiece changes. Therefore, it is preferable to switch the frequency, matching conditions, etc. in a time zone lower than that temperature. In the above description, switching is performed in units of induction heating time. However, when the heating temperature of the workpiece W is monitored by a non-contact sensor and reaches a predetermined temperature, the circuit setting conditions may be changed.

[Displacement means]
The displacement means 460 displaces the relative position between the workpiece W and the heating coil 451 and changes the relative angle.
As shown in FIG. 8, the displacing means 460 includes a vertical displacement portion 462 that vertically displaces the support box 452 and a horizontal displacement that horizontally displaces the support box 452 along the radial direction from the rotation center C of the workpiece W. A portion 463 and an angle turning portion 492 for adjusting the inclination of the support box 452.

The vertical displacement unit 462 includes a displacement frame 42 fixed on the heating / cooling frame 40, a lower frame 464 disposed on the displacement frame 42, and a vertical drive mechanism 465 that moves the lower frame 464 up and down with respect to the displacement frame 42. With.
The vertical drive mechanism 465 is fixed to the lower frame 464 and disposed in the vertical direction. The displacement guide rod 466 and the longitudinal displacement screw shaft 467 are fixed to the displacement frame 42 and support the displacement guide rod 466 so as to be movable up and down. A bearing 468, a vertical drive motor 469 composed of a servo motor or the like fixed to the displacement gantry 42, and a connecting body 471 provided on the displacement gantry 42 and vertically moving the vertical displacement screw shaft 467 by the rotation of the vertical drive motor 469. Prepare.

  The horizontal displacement portion 463 includes a first displacement rail 472 disposed on the lower platform 464 in a direction substantially perpendicular to the radial direction of the workpiece W, an upper platform 473 movable on the first displacement rail 472, and an overhead A first displacement driving mechanism 474 that moves the table 473 along the first displacement rail 472; and a second displacement rail 475 disposed on the upper table 473 along the radial direction of the workpiece W. And a second displacement drive mechanism 476 for moving the support box 452 supported on the rail 475 along the second displacement rail 475.

  The first and second displacement drive mechanisms 474 and 476 are connected to a displacement drive motor 477 made of a servo motor and the like, respectively, and are arranged along the first or second displacement rails 472 and 475 to rotate. A lateral displacement screw shaft 478 to be driven and a displacement protrusion 479 provided on the upper base 473 or the support box 452 and screwed with the lateral displacement screw shaft 478 are provided. If the heating coil 451 can be aligned in advance in a direction substantially orthogonal to the radial direction of the workpiece W, the first displacement drive mechanism 474 may not be provided.

  The angle turning portion 492 is provided in the support box 452, and for example, the upper portion of the support box 452 is placed on the front side and the rear side with respect to the lower portion of the support box 452 supported by the first or second displacement rails 472 and 475. The inclination of the support box 452 is changed by raising or lowering to different heights. Although detailed illustration is omitted, in order to ascend or descend each position of the support box 452, a male screw portion that is rotated by a step motor is provided at the upper and lower portions, and a female screw that is screwed into the male screw portion is provided on the other side. A screw part is provided.

  By changing the height of the support box 452 on the workpiece W side and the opposite side by the angle turning portion 492, the heating coil 451 is turned around an axis along one longitudinal direction of the heated region H. be able to. Here, the axis along one direction is an axis parallel to the workpiece W when the workpiece W is linear, and an axis parallel to the annular tangent line when the workpiece W is annular.

[Attitude control unit]
The displacement means 460 is provided with a posture control unit 490 that adjusts the relative position and relative angle between the workpiece W and the heating coil 451 by controlling the operation of the displacement means 460 based on the detection result of the position detection means 480. ing. As shown in FIG. 8, the posture control unit 490 is provided in a state of being incorporated in the operation unit 710 of the electrical equipment, and is configured to control each driving device of the displacement unit 460.

  The posture control unit 490 passes each detection position based on the displacement amount of the workpiece W and the rotation speed of the rotation drive motor 255 based on a signal indicating the measurement position of the workpiece W measured by the position detectors 483 and 484. The timing at which each part on the surface of the workpiece W passes through each heating unit 450 immediately downstream is obtained. Therefore, when each part passes through the heating position P3, the position of the heating coil 451 can be made to follow the workpiece W by being displaced by the displacing means 460 so as to correspond to the position.

By the way, when the heated region H of the workpiece W as in the present embodiment is dielectrically heated by the heating coil 451 facing the heated region H with a predetermined gap, one edge side and the other edge side of the heated region H are Since the deformation amount differs, the workpiece W is deformed unevenly.
While rotating the workpiece W in a normal temperature state as shown by a solid line in FIG. 15, a heated region H between c <b> 1 and d <b> 1 of the inner circumferential surface of the workpiece W is below the inner circumferential surface shown by a broken line in the drawing. Heat while cooling the side with coolant. Then, as the heated area H rises, the workpiece W thermally expands non-uniformly as indicated by the phantom line in the figure, resulting in different deformation amounts on one edge side and the other edge side of the heated area H. As a result, the heated region H is located between c2 and d2. Note that the deformation is exaggerated in the figure for easy understanding.

  At this time, the contact 488 of the radial position detector 483 measures a1 on the outer peripheral surface of the workpiece W at a low temperature, and measures a2 after the temperature rise due to deformation of the workpiece W. Further, the contact 488 of the axial position detector 484 measures b1 on the side peripheral surface of the workpiece W when the temperature is low, and measures b2 after the temperature rises. Therefore, the measurement positions measured as a1 and b1 in the position detection means 480 are measured as a2 and b2 after the temperature rise. In that case, the heating coil 451 is displaced and heated corresponding to the change from the measurement position at the low temperature to the measurement position at the high temperature.

  However, since the workpiece W is deformed unevenly, the actual heated region H is changed from the position c1-d1 to the position c2-d2. Here, as is apparent from the figure, the amount of change between c1 and c2 and the amount of change between d1 and d2 are larger than the amount of change between a1 and a2 and the amount of change between b1 and b2. Is big.

  Therefore, if the workpiece W is heated by each heating coil 451 based on only the measurement position measured by the position detection means 480, the workpiece W is heated to the position shown by the imaginary line in the figure corresponding to the measurement position as it is. The coil 451 is disposed, and the heating coil 451 and the heated area H are heated at a high temperature in a state where the relative positions are shifted unevenly. In addition, the upper edge side of the heated region H on the side far from the heating coil 451 has a larger volume of the workpiece W than the lower edge side and a larger heat capacity. As a result, on the lower edge side of the heated region H, the heated region H cannot be heated uniformly, for example, when the temperature can be raised to the desired temperature, the upper edge side cannot raise the temperature to the desired temperature. .

Therefore, in the heat treatment apparatus 10 of this embodiment, in order to prevent such uneven heating of the heated region H, the heating coil 451 is configured based on the heating condition of the workpiece W and the heating state during the heating period. By adjusting the position and tilt angle, a function is provided to enable uniform heating.
Here, the heating conditions include, for example, the shape, size, and material of the workpiece W, the shape of the heating coil 451, the facing area, the moving speed of the workpiece W, the voltage of the high-frequency power supplied to the heating coil 451, the current, the frequency, and the heating time. The cooling position of the workpiece W, the coolant temperature, and the like. The heated state is the surface temperature of the heated region H, the elapsed heating time, and the like.
In this attitude control unit 490, after the induction heating is started by the heating coil 451 under preset heating conditions, the position and inclination of the heating coil 451 are set in an appropriate heating state, preferably in a preset heating state. Adjust the angle. This makes it possible to heat the entire heated region H as uniformly as possible, and to improve the heating efficiency with respect to the supplied power due to gap deviation or the like.

Specifically, it has the following functions.
First, the measurement position obtained from the detection result of each position detection means 480 at the time of heating, that is, the detection result measured in a portion other than the heated region H, is corrected based on at least the workpiece shape, and obtained by correction. It has a function of controlling the operation of the displacement means 460 so as to correspond to the correction position.
When the gap between the heating coil 451 and the heated region H is uniform throughout the heating coil 451, the reference position is between the surface of the heating coil 451 facing the heated region H and the surface of the heated region H. It is preferable that the distance be a predetermined value. When the gap between the heating coil 451 and the heated region H is not uniform, an appropriate point on the surface of the heating coil 451 facing the heated region H and a point facing the point of the heated region H It can be set as the position where the distance between becomes a predetermined value.

  In the present embodiment, in the position detection unit 480, the measurement positions detected by the radial position detection unit 483 and the axial position detection unit 484 are the amount of displacement from the reference position, and the correction position is the amount of displacement. Is the amount of misalignment correction. The posture control unit 490 controls the operation of the displacement unit 460 so as to correspond to the positional deviation correction amount.

In order to correct the measurement position, the data of the measurement position can be corrected using the correction coefficient. For example, the correction position can be obtained by multiplying the signal indicating the measurement position by the correction coefficient. This correction coefficient is a value corresponding to at least the workpiece shape, and the heating coil 451 can be disposed more accurately with respect to the heated region H by setting the correction coefficient corresponding to more heating conditions. .
Such a correction coefficient may be obtained empirically. Further, the deformation of the workpiece W in the set heating state at the time of heating is calculated based on the heating condition, the set heating state, etc., and the portion of the part measured by the radial position detecting unit 483 and the axial position detecting unit 484 of the position detecting unit 480 is calculated. The correction coefficient may be obtained from the deformation amount and the displacement amount of the heated region H obtained by calculation. Further, a simulation process step for obtaining a correction coefficient may be set in advance in the attitude control unit 490, and the correction coefficient may be obtained by this simulation process.
Such a correction coefficient may be input during heating or before heating, or may be stored in the attitude control unit 490.

  This correction coefficient is preferably different between a low temperature and a high temperature. When the set heating state is reached, for example, when the temperature of the heated region H reaches a predetermined temperature range such as 700 to 800 degrees, or It can be changed manually or automatically when a predetermined time has elapsed after the start of heating.

Next, the posture control unit 490 of this embodiment has a function of displacing some or all of the positions of the plurality of heating coils 451 during the heating period.
By controlling the posture control unit 490 and displacing each heating coil 451 by the displacing means 460, the opposing areas of the plurality of heating coils 451 and the heated region H are adjusted so as to change in the width direction of the heated region. To do. For example, each heating coil 451 is disposed at substantially the same position in the width direction of the heated area H of the workpiece W at the start of the heating period, and when the predetermined heating state is reached, each heating coil 451 is placed in the heated area H. The positions in the width direction are displaced individually or in combination. All the heating coils 451 may be displaced.

  The arrangement and displacement amount of the plurality of heating coils may be determined based on experience. Further, it may be determined so as to correspond to a change in the gap between the heated region H and each heating coil 451 or the gap during the heating period, and the set heating state at the time of heating based on the heating condition, the set heating state, etc. The deformation of the workpiece W may be calculated so as to correspond to the calculation result. Depending on the temperature distribution in the width direction of the heated region H, it may be determined that a larger area of the heating coil 451 is arranged on the low temperature side. Furthermore, it is also possible to set a step of simulation processing for determining the arrangement of the plurality of heating coils 451 in advance in the attitude control unit 490, and to determine by this simulation processing. Here, the deformation amount in the width direction of the heated region H may be obtained by simulation processing, and the area may be adjusted to correspond to the deformation amount, or may be selected from accumulated data related to the arrangement.

In order to displace the heating coil 451 during the heating period, a part of the heating coils 451 of all the heating coils 451 may be shifted to the edge side. Further, the arrangement to be displaced in advance may be stored in correspondence with the set heating condition, and may be displaced manually or automatically when the set heating condition is reached.
In the state where the arrangement of the heating coils 451 is displaced, a part of the heating coils 451 different from each other is arranged at the same position in the width direction of the heated region H, and the same position in the width direction of the heated region H is superimposed. It is also possible to arrange it to be heated.
Thereby, the arrangement distribution of the plurality of heating coils 451 in the width direction of the heated region H is adjusted to be different before and after the displacement of the heating coil 451, and the amount of heat generated during induction heating is adjusted appropriately. Can do.

  Next, the posture control unit 490 of the present embodiment adjusts the posture, which is a relative angle with respect to the heated region H, of the heating coil 451 by changing the posture of the support box 452, and the heated region H of the heating coil 451. It has the function to arrange | position so that the surface which opposes to the to-be-heated area | region H in a heating period. Here, during the heating period, adjustment is made so that the difference in angle between the surface of the heating coil 451 facing the heated region H and the heated region H is reduced or eliminated. When the surface of the heating coil 451 that faces the heated region H and the shape of the heated region H are not the same shape, the surface of the heating coil 451 that faces the heated region H and the heated region H are adjusted by adjusting the posture. The difference in angle between and should be as small as possible.

The amount of adjustment of the posture of the heating coil 451 may be determined based on experience. Also, deformation of the workpiece W in the set heating state during heating based on the change in the gap between the heated region H and each heating coil 451 and the gap during the heating period, or based on the heating conditions, the set heating state, etc. May be determined so as to correspond to the calculation result. In correspondence with the temperature distribution in the width direction of the heated region H, the heating coil 451 may be determined closer to the low temperature side.
Furthermore, it is also possible to set a simulation process step for determining the attitudes of the plurality of heating coils 451 in advance in the attitude control unit 490, and to determine by this simulation process. Here, the deformation amount in the width direction of the heated region H may be obtained by simulation processing, and the posture adjustment amount may be determined so as to correspond to the deformation amount.

  In order to adjust the posture by changing the direction of the heating coil 451 during the heating period, the posture control unit 490 may be operated during the heating period based on experience. Alternatively, the posture may be stored in advance corresponding to the set heating condition, and the orientation may be changed manually or automatically when the set heating condition is reached.

As shown in FIG. 16, the posture control unit 490 of the present embodiment includes a setting input unit 493 that inputs a heating condition and a set heating state of the workpiece W, a displacement unit based on the heating condition and the set heating state of the workpiece W, and the like. An arithmetic processing unit 494 for calculating the control amount, a storage unit 495 for storing various setting values input to the setting input unit 493 and arithmetic results obtained by the arithmetic processing unit, and a heating state of the heated region H are set. A heating state determination unit 496 that determines that the heating state has been reached, and a drive control unit 497 that drives the displacement means 460 when the set heating state is reached are provided.
Here, the elapsed heating time is used as the heating state, but it is also possible to use the temperature of the heated region H as the heating state. In this case, as shown by a broken line in FIG. 16, the temperature of the heated region H is detected by a non-contact type temperature sensor, and the set heating state is detected by the heating state determination unit 496 reaching the preset temperature. May be determined.

  The storage unit 495 stores a step for causing the heating coil 451 to follow and displace the position of the workpiece W at the heating position P3 based on a signal from the position detection unit 480 after the start of heating. Information for adjusting the heating conditions and the relative position and relative angle of the heating coil 451 with respect to the heated region H is stored in combination with the set heating state. These may be input by the setting input unit 493 or may be obtained by calculation.

Further, the storage unit 495 stores processing step information for simulation processing.
The step of the simulation process is for calculating the deformation state when the heated region H reaches the set heating state under the heating condition, and the method is not particularly limited. For example, a simulation process for obtaining thermal deformation by a two-dimensional FEM (Finite Element Method) analysis model may be employed.

[Power adjustment means]
The power adjustment unit 491 is set as a part of the operation unit 710 of the power supply facility 700. In the power adjusting means 491, the high frequency power supplied to the plurality of heating coils 451 is adjusted separately for each heating coil 451. The high-frequency power may be adjusted to the high-frequency power set corresponding to the set heating state at the time when the preset set heating state is reached and thereafter.
In this power adjustment means 491, the high-frequency power supplied to each heating coil 451 is varied in combination with the adjustment of the relative position and relative angle between each heating coil 451 and the heated region H by the attitude control unit 490. Thus, the heated region H is heated by the plurality of heating coils 451.

[Hardening method]
Next, a method for quenching the workpiece W using such a heat treatment apparatus 10 will be described.
In the quenching method of the present embodiment, a preparation process for setting each part according to the workpiece W, a loading process for loading the workpiece W and placing it on the jig 100, and conveying the jig 100 on which the workpiece W is loaded. A heating process for induction heating the work W on the jig 100, a cooling process for cooling the work W on the jig 100, and an unloading process for unloading the work W after quenching.

  In the preparation process, each part is set according to the size and shape of the workpiece W to be heat-treated. The component parts of the heating unit 450 such as the heating coil 451 can be mounted on the heating unit 450 using the component replacement section 600 and the component replacement jig 620 shown in FIGS.

In the carry-in process, the work W to be heat-treated is carried in by the carry-in / out section 300 shown in FIGS. 2 and 3 and placed on the jig 100 so as to be transportable.
The workpiece W is supported by the jig 100 at the loading / unloading position P1 of the loading / unloading section 300. As shown in FIG. 4, the work W is placed on the plurality of rotating rollers 112 of the jig 100 so as to surround the central structure 130 and have one end face facing downward. Thereafter, the jig 100 on which the workpiece W is placed is moved to the hanging position P2 and stopped.
In the transfer process, as shown in FIGS. 3 and 4, the jig 100 on which the workpiece W is placed is connected to the transfer loader unit 220 of the transfer mechanism 200 and is suspended and transferred to the heating section 400.

In the heating process, the jig 100 is arranged at a predetermined position in the heating section 400 shown in FIGS. 1 and 2, and the jig 100 is arranged on the jig 100 by restricting the movement in the vertical direction and the circumferential direction. The mounted work W is placed at each heating position P3 and heated.
In the heating process, a heat treatment step as shown in FIG. 17 is executed.

  First, before starting the heat treatment, the heating conditions as described above are input from the setting input unit 493 in the input step S1. This input can be input from the touch panel of the operation unit 710 or the portable terminal 701. Each item is selected from the main menu as shown in FIG. 5, and various heating conditions are input on the input enabled screen. At this time, since the non-uniform deformation of the workpiece W is increased in advance, the deviation between the measurement position measured by the position detection unit 480 and the position of the heated region H of the actually heated workpiece W may increase. One or a plurality of set heating states to be predicted are set.

  In the simulation step S <b> 2, based on the input heating condition, the simulation processing is performed based on the simulation processing steps stored in the storage unit 495 by the arithmetic processing unit 494. In this process, the correction coefficient in each set heating state, the arrangement of each of the plurality of heating coils 451 in the width direction of the heated region H, the inclination of each heating coil 451 are calculated, and the obtained calculation results are respectively set heating. The data is stored in the storage unit 495 in a state corresponding to the state.

After performing the simulation step S2, in the processing start step S3, in a state where the workpiece W is arranged at each heating position P3, the rotation roller 112 is rotated to rotate the workpiece W along the ring shape, and the rotation drive unit 30, the peripheral speed of the workpiece W is kept constant. At this time, since the rotation roller 112 feeds the mechanism, the workpiece W can be easily rotated at a predetermined peripheral speed regardless of the diameter of the workpiece W by adjusting the rotation speed of each rotation roller 112. Further, if the upper side of the peripheral surface of each rotating roller 112 is provided with an inclination in the diameter direction of the workpiece W, in particular, an inclination that decreases outward, the workpiece W is rotated to align the workpiece W. Also good.
As shown in FIG. 9, the measurement position is measured by bringing the contact 488 of the position detectors 483 and 484 into contact with the middle and upper surfaces of the outer peripheral surface of the workpiece W. As shown in FIG. 8, cooling is started by injecting a cooling liquid from the heating / cooling unit 440 to the lower side adjacent to the heated region H to be heated.

  The heating coil 451 is displaced by operating the displacing means 460 under the control of the attitude control unit 490, and the heating coil 451 is disposed opposite to the heated area H of the workpiece W so as to form a predetermined gap. At this time, since the deformation of the workpiece W and the measurement position measured by the position detection means 480 substantially coincide with each other at the heating start time, the correction coefficient can be set to 1. Further, since the heating coil 451 is previously supported by the support box 452 so as to have an inclination corresponding to the inclination in the width direction of the heated region H, the support box 452 of the displacing means 460 is in a substantially horizontal state. There is no difference in the relative angle between the coil 451 and the heated region H. Further, all of the plurality of heating coils 451 may be arranged around the center line in the width direction of the heated region H.

In this state, the induction heat treatment step S4 is started. In the induction heat treatment step S4, high-frequency power is supplied to the heating coil 451 and the heated region H is induction-heated while continuing to rotate, cool, and measure the measurement position of the workpiece W.
By detecting the displacement amount of the contact 488 of the radial position detector 483 of each position detector 480 and the axial position detector 484 by the change amount detector 489, the measurement position of the heated region H at each heating position P3. Has been measured. Therefore, each heating coil 451 can be heated while following the workpiece W. For example, even when the workpiece W is arranged while being eccentric from the center of the jig 100, the heating coil 451 is placed in the workpiece W even when the workpiece W is rotated while being displaced in the radial direction. It can be made to follow and heat.
In this induction heat treatment step S4, the heating state is continuously detected from the start of heating, and the elapsed heating time from the start of heating is detected as the heating state.

Since the workpiece W is large and is heated by a plurality of heating coils 451 arranged at intervals in the circumferential direction, the heating period of the induction heating process S4 may be several minutes. During this heating period, the heating state and the position of the workpiece W are monitored, and the operator can check the operation unit 710 or the portable terminal 701 on a monitor screen or the like.
By continuing such induction heating processing, the heated region H and the workpiece W are heated. At the same time, the workpiece W is gradually deformed unevenly due to thermal expansion.

  When the heating state determination unit 496 determines that the heating state has reached the set heating state, the arithmetic processing unit 494 changes the correction coefficient in the set heating state stored in the storage unit 495. Using this correction coefficient, the measurement position measured by the position detection means 480 is corrected, and the correction position is calculated. Thereby, in the high temperature state after the set heating condition, the follow-up operation is performed by regarding the position of the heated region H at each heating position P3 as the correction position until the next set heating condition is reached. That is, the posture control unit 490 controls the operation of the displacement unit 460 so as to correspond to the change in the correction position, and the relative position between the heating coil 451 and the heated region is stably maintained.

When it is determined that the heating state has reached the set heating state, the arithmetic processing unit 494 causes the posture control unit 490 to have the inclination of each heating coil 451 in the set heating state stored in the storage unit 495. Thus, the operation of the displacement means 460 is controlled. Here, in the angle turning portion 492, the angle of the surface of the heating coil 451 that faces the heated region H is set by raising or lowering the upper portion of the support box 452 to different heights on the front side and the rear side. The inclination angle of each heating coil 451 in the heated state is adjusted.
For example, as shown in FIG. 18, each heating coil 451 is arranged with an inclination as shown by a solid line in the drawing until the set heating state is reached. After reaching the set heating state, the inclination of the heated region H changes due to unequal deformation of the workpiece W, so that the inclination is inclined at an angle θ as shown by the phantom line in the figure so as to correspond to this change. The gap between each heating coil 451 and the heated area H is made more uniform.
In a high temperature state after the set heating condition, this angle is maintained until the next set heating condition is reached.

When it is further determined that the heating state has reached the set heating state, the arithmetic processing unit 494 causes the posture control unit 490 to displace the displacement means so that the plurality of heating coils 451 stored in the storage unit 495 are arranged. The operation of 460 is controlled. Here, since the edge side in the width direction of the heated region, in particular, the upper edge side is displaced in a direction away from each heating coil 451 due to, for example, unequal deformation of the workpiece W, the amount of heat generated by induction heating is larger than that of the intermediate portion or the like. For example, the surface temperature of the heated region H is uneven, and the temperature is likely to be lower than that of the intermediate portion.
Therefore, as shown by a solid line in FIG. 19, before reaching the set heating state, the positions of the plurality of heating coils 451 in the width direction of the heated region H are equally arranged. As shown, the positions of some of the heating coils 451 are shifted to the edge side of the heated region H. If necessary, all of the plurality of heating coils 451 may be arranged even on the edge side. Thereby, the distribution of the opposed area of the heating coil 451 in the width direction of the heated area H is adjusted, and each heating coil 451 is arranged so that the opposed area on the low temperature side of the heated area H becomes larger, and the heat generation on the low temperature side Make the amount larger.
In the high temperature state after the set heating condition, this angle is maintained until the next set heating condition is reached.

  By repeating such control one or more times, the induction heat treatment step S4 is performed until the heating is completed, and the entire heated region H is uniformly heated. When the temperature of the heated region H reaches a desired temperature, or when a predetermined heating time is finished, the induction heating process S4 is finished.

After the induction heat treatment step S4 is completed, in the cooling step, the jig 100 is lowered by the transfer loader unit 220, the workpiece W on the jig 100 is placed in the cooling section 500, and the workpiece W is rotated while being moved to a plurality of positions. A large amount of coolant is sprayed onto the workpiece W from the cooling jacket 520 provided on the workpiece W to cool the entire workpiece W. Here, since the cooling section 500 is provided below the heating section 400, the cooling is started within a short time after the heating. Thereby, the desired hardening process of the workpiece | work W is performed.
When the temperature of the heated area H of the workpiece W is sufficiently lowered, the cooling process is finished.

  After that, the hardened workpiece W is hung on the transfer loader unit 220 together with the jig 100 and transferred to the carry-in / out section 300, and the hardening process of the work W is completed.

  According to the heat treatment apparatus 10 and the heating method as described above, the displacement means 460 for separately displacing the positions of the plurality of heating coils 451 in the width direction of the heated region H is provided. By displacing the position, the arrangement distribution of the plurality of heating coils 451 in the width direction of the heated region H is adjusted, so that the heat generation site by induction heating can be adjusted for each heating coil 451. Therefore, the heat generation amount distribution in the width direction of the heated area H can be adjusted, the temperature of the heated area H can be prevented from becoming non-uniform in the width direction of the heated area H, and the entire heated area H can be uniformly determined. The temperature can be raised to

Here, power adjustment means 491 for separately adjusting the high frequency power supplied to each heating coil 451 is provided, the position of each heating coil 451 is adjusted, and the high frequency power supplied to each heating coil 451 by the power adjustment means 491 is varied. The heated area H is heated. Therefore, the heat generation amount distribution in the width direction of the heated region H can be adjusted more appropriately, and it is easy to raise the temperature of the entire heated region H uniformly to a predetermined temperature.
Since the plurality of coils have the same shape, it is easy to manufacture the plurality of heating coils 451, and the correction coefficient can be manufactured at a lower cost.

A posture control unit 490 that controls the operation of each displacement means 460 is provided, and the position of each heating coil 451 is displaced by the posture control unit 490 corresponding to the gap between the heated region H and each heating coil 451. . Therefore, when the workpiece W is deformed unevenly as the temperature rises, the effort for adjusting the direction of the heating coil 451 can be simplified or eliminated.
The position of the plurality of heating coils 451 is displaced during the heating period by the attitude control unit 490. Therefore, even if the workpiece W is deformed more greatly in a high temperature state, the entire width of the heated region H can be heated uniformly.

In addition, the said embodiment can be suitably changed within the scope of the present invention.
For example, in the above description, the arrangement distribution of the plurality of heating coils 451 in the width direction of the heated region H is adjusted, the measurement position detected by the position detection unit 480 is corrected, or the heated region H is heated. However, the distribution of the plurality of heating coils 451 in the width direction of the heated region H can be further improved without correcting the measurement position or adjusting the angle of the heating coil 451. By appropriately adjusting, it is possible to reduce the unevenness of the non-uniform heating state of the heated region and achieve uniformization.

The example in which all the heating coils 451 are separately displaced by the displacing means 460 has been described above, but a plurality of, for example, two heating coils 451 may be combined and displaced.
The arrangement of the plurality of heating coils 451 is foreseen in advance that the gap is displaced and the temperature distribution of the heated region H is uneven, and the arrangement is adjusted in advance so that the heating can be performed uniformly. Also good.
As the workpiece W, the present invention can be applied even if the deformation amount does not differ between one edge side and the other edge side of the heated region H when the heating region is induction-heated. That is, by applying the present invention when the temperature distribution of the heated region H is non-uniform during heating and adjusting the arrangement of the heating coils 451, the unevenness of the heating state can be reduced and heated uniformly.
In the above, the example in which the width of the heated region H and the width of the heating coil 451 are approximated has been described, but the present invention is also applied to the case where heating is performed with a plurality of heating coils 451 having a width narrower than the width of the heated region H. Applicable. In that case, the workpiece W having a different length in each section when the entire length of the heated area H is divided into strip-shaped sections arranged in the width direction is heated by a plurality of heating coils 451 having a width narrower than the width of the heated area H. In this case, the plurality of heating coils 451 may be arranged so as to set the facing areas of the plurality of heating coils 451 according to the length of the strip-shaped section. For example, more heating coils 451 having the same shape can be arranged in a long section than in a short section.

W Work W1 Base W2 Projection W3 Inclined surface H Heated area C Rotation center P1 Loading / unloading position P2 Hanging position P3 Heating position 10 Heat treatment apparatus (heating apparatus)
40 Heating / cooling frame 42 Displacement frame 43 Position detection column 44 Position detection table 100 Jig 110 Work support part 111 Radiation frame 112 Rotating roller (relative movement means)
130 Central structure 200 Transport mechanism 210 Transport rail 220 Transport loader section 246 Rotation drive means 255 Rotation drive motor 300 Loading / unloading section 400 Heating section 410 Jig holding mechanism 440 Heating / cooling section 450 Heating section 451 Heating coil 452 Support box 460 Displacement means 461 Position adjustment handle 462 Vertical displacement portion 463 Horizontal displacement portion 464 Lower base 465 Vertical drive mechanism 466 Displacement guide rod 467 Vertical displacement screw shaft 468 Displacement bearing 469 Vertical drive motor 471 Connecting body 472 First displacement rail 473 Upper base 474 First displacement Drive mechanism 475 Second displacement rail 476 Second displacement drive mechanism 477 Displacement drive motor 478 Lateral displacement screw shaft 479 Displacement protrusion 480 Position detection means 481 First advance / retreat mechanism 482 Second advance / retreat mechanism 483 Radial position detector 484 Axis Direction / position detector 485 Advance / retreat drive means 486 Rod 487 Guide rod 488 Contact 489 Change amount detection section 490 Attitude control section 491 Power adjustment section 492 Angle turning section 493 Setting input section 494 Calculation processing section 495 Storage section 496 Heating state determination Unit 497 drive control unit 500 cooling section 600 parts replacement section 700 power supply equipment 701 portable terminal 702 cable 710 operation unit 711 input / output screen 722, 722A, 722B, 722C transformer 723, 723A, 723B, 723C matching unit 724 inverter 724A Conversion unit 724B Reverse conversion unit 725 Inverter control unit 725A Forward conversion control unit 725B Reverse conversion control unit 726 Switch group 726A, 726B, 726C, 726D, 726E Switch 727 Switching control unit

Claims (9)

A heating device that inductively heats a workpiece that extends in one direction and has a heated region set,
A plurality of heating coils opposed to a part of the heated region; a relative moving means for relatively moving the work and the plurality of heating coils along the one direction; and a position of the heating coil as the heated region. Displacement means for separately displacing in the width direction of
By displacing each heating coil by the displacing means, the opposing areas of the plurality of heating coils and the heated region are adjusted so as to change in the width direction of the heated region, and the plurality of heating coils An induction heating apparatus that heats the heated area by the above. Power adjustment means for separately adjusting the high-frequency power supplied to the plurality of heating coils,
The position of each said heating coil is adjusted with the said displacement means, The said to-be-heated area | region is heated with the said some heating coil by varying the high frequency electric power supplied to each said heating coil with the said power adjustment means. 2. The induction heating apparatus according to 1.   The induction heating device according to claim 1, wherein the plurality of coils have the same shape.   The induction heating device according to any one of claims 1 to 3, wherein the workpiece has a deformation amount different between one side edge side and the other side edge side of the heated region when the heating region is induction-heated. .   The displacement means is provided with an attitude control unit that controls the operation of the displacement means, and the attitude control unit is configured to position the heating coils in correspondence with the gaps between the heated area and the heating coils. The induction heating device according to claim 4, wherein the induction heating device is displaced.   The induction heating apparatus according to claim 5, wherein the posture control unit displaces positions of the plurality of heating coils during a heating period. The posture control unit includes a setting input unit that inputs a heating condition of the workpiece, and the plurality of heating coils corresponding to gaps between the heating region and the plurality of heating coils in an assumed heating state of the heated region. An arithmetic processing unit that determines the arrangement of the heating region, a heating state determination unit that determines that the heating state of the heated region has reached the assumed heating state, and a plurality of heating coils when the assumed heating state is reached. A drive control unit that drives the displacement means based on the arrangement,
The induction according to claim 5 or 6, wherein the calculation processing unit calculates the gap in the assumed heating state based on the heating condition by a preset simulation process and determines the arrangement of the plurality of heating coils. Heating device. It is a heating method for induction heating a work extending in one direction and having a heated area set,
A heating step in which a heating coil is opposed to a part of the heated region, and the workpiece is heated by the heating coil while the workpiece and the heating coil are relatively moved along the one direction;
By separately displacing the plurality of heating coils in the width direction of the heated region during the heating period, the facing area of the plurality of heating coils and the heated region changes in the width direction of the heated region. Adjust the induction heating method.   The induction heating method according to claim 8, wherein the gaps in the assumed heating state are calculated based on heating conditions by a preset simulation process to determine the arrangement of the plurality of heating coils.

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