JPH08246038A - High-frequency induction heating device - Google Patents

Abstract

PURPOSE: To unnecessitate periodical maintenance or exchange by executing the connection of a heating coil to a current transformer in a non-contact state. CONSTITUTION: One set of the current transformer 200 and two pieces of heating coils 100A, 100B for supplying electric current from the current transformer 200 are provided, and each of heating coils 100A, 100B heats a work W in order. A shifting mechanism 300 for shifting a loop-like terminal part 220 of output terminal 210 of the current transformer 200 relatively to loop-like conducting parts 141A, 141B respectively of current supplying conductors 140A, 140B of respective heating coils 100A, 100B, is provided. The shifting mechanism 300 is the one to face the loop-like terminal part 220 to the loop-like conducting parts 141A, 141B of the two heating coils 100A, 100B in order at a prescribed interval. The current is passed to each of the heating coils 100A, 100B with a secondary induction between the faced loop-like terminal part 220 and each of the loop-like conducting parts 141A, 141B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency heating device, and more particularly to a high-frequency heating device having a plurality of heating coils which are alternately supplied with power from one current transformer.

[0002]

2. Description of the Related Art The applicant of the present application has previously filed Japanese Utility Model Application No. 4-410.
Filed No. 11. The induction hardening apparatus according to this application is
As shown in FIG. 8, one current transformer 40, two heating coils 10 and 20 fed from this current transformer 40, and power to the two heating coils 10 and 20 are alternately fed. The two contact pieces 51 (However,
Only one is shown in the drawing).

Connecting conductor 4 of two heating coils 10, 20
Connect 1, 42 to the output terminal of the current transformer 40,
The connection conductors 41 and 42 are driven by a cylinder 53.
The contact pieces 51 are alternately short-circuited to alternately supply power to the heating coils 10 and 20.

In the drawing, reference numeral 30 designates the cooling liquid L as a work W.
Cooling jacket for spraying toward the connection conductor 44
An insulating member that is provided between the first and the second parts to insulate the two.

[0005]

However, the induction hardening apparatus according to the above-mentioned Japanese Patent Application No. 4-41011 has the following problems. That is, the contact piece 51 includes the protrusions 41 a, 42 b, 43 formed on the connection conductors 41, 42.
The contact piece 51 and the protrusions 41a, 42b, 43a, 43b are repeatedly contacted with the contact pieces 51, 43a, 43b.
Wear and roughening of the surface, and as a result, the contact piece 51 and the convex portion 4
Sparks may occur between 1a, 42b, 43a, and 43b, or connection failure may occur. Therefore, in this induction hardening apparatus, it is necessary to regularly maintain or replace the short-circuit means, which causes time loss and high cost.

The present invention has been devised in view of the above circumstances, and by performing the connection between the heating coil and the current transformer in a non-contact state, it is possible to perform the periodic maintenance or replacement required in the conventional high frequency heating device. It is an object of the present invention to provide a high-frequency heating device which is unnecessary and eliminates the time loss and the associated high cost.

[0007]

A high frequency heating apparatus according to the present invention has one current transformer and a plurality of heating coils fed from the current transformer, and each heating coil holds a workpiece. A high-frequency heating device for sequentially heating, comprising a moving mechanism for relatively moving an output terminal of a current transformer and a feeding conductor of each heating coil so that the output terminal and the feeding conductor face each other at a predetermined interval. , Is configured to flow a current through the heating coil by secondary induction between the output terminal and the power supply conductor which face each other.

[0008]

1 is a schematic side view showing the configuration of a high frequency heating apparatus according to a first embodiment of the present invention, FIG. 2 is a schematic perspective view of a heating coil used in this high frequency heating apparatus, and FIG. FIG. 4 is a sectional view taken along the line AA of FIG. 1 showing a state in which the output terminal of the current transformer used in this high-frequency heating device and the power supply terminal of the heating coil are opposed to each other, and FIG. 4 is the output terminal of the current transformer used in this high-frequency heating device. And a feeding terminal of the heating coil are opposed to each other, and FIG. 5 is a schematic side view showing a configuration of a high-frequency heating device using another moving mechanism.

FIG. 6 is a schematic side view showing the structure of a high-frequency heating apparatus according to the second embodiment of the present invention, and FIG. 7 shows the structure of a high-frequency heating apparatus according to the third embodiment of the present invention. It is a schematic plan view.

The high frequency heating apparatus according to the first embodiment is
Table current transformer 200, and two heating coils 100A, 10 fed from this current transformer 200
0B and each heating coil 100A, 100B
Is a high-frequency heating device for alternately heating the work W,
By moving the current transformer 200, the loop-shaped terminal portion 2 of the output terminal 210 of the current transformer 200 is moved.
20 and the feeding conductor 14 of each heating coil 100A, 100B
The moving mechanism 300 is provided to face either one of the loop-shaped conductor portions 141A and 141B of 0A and 140B with a predetermined interval.

One high-frequency power source (not shown) is connected to the current transformer 200. On the outer surface of the current transformer 200, a guide 310 that constitutes a moving mechanism 300 described later is provided.

A loop-shaped terminal portion 220 having a loop shape is provided at the tip of the output terminal 210 of the current transformer 200. Such a loop-shaped terminal portion 22
0 is composed of a hollow pipe having a substantially square cross section,
As shown in FIG. 4, three surfaces other than the inner surface 221 are covered with a core 230 made of a magnetic material and having a substantially U-shaped cross section.

The moving mechanism 300 has, in addition to the guide 310 provided on the current transformer 200, a ball screw member 320 into which the guide 310 is fitted, and a drive source 330 for rotationally driving the ball screw member 320. ing.

As shown in FIG. 2, one heating coil 100A is of a semi-open saddle type and has a pair of heating conductors 110A corresponding to the shape of the work W to be heated, and the pair of heating conductors 110A. ½ arc-shaped connection conductor 120A connecting one end of the heating conductor and a pair of ¼ arc connection conductors 130 connected to the other end of the heating conductor 110A.
A and the power supply conductor 14 connected to this connection conductor 130A
It has 0A.

The feed conductor 140A is composed of a loop conductor portion 141A formed in a substantially loop shape and a pair of connection conductor portions 142A for connecting the loop conductor portion 141A to the connection conductor 130A. There is.

As shown in FIG. 3, the outer diameter of the loop-shaped conductor portion 141A is set smaller than the inner diameter of the loop-shaped terminal portion 220 by a predetermined dimension. Furthermore, FIG.
As shown in, the outer surface 1 of the loop-shaped conductor portion 141A
The three surfaces other than 41a are covered with a core 150 made of a magnetic material and having a substantially U-shaped cross section.

Further, the connecting conductor portion 142A is formed in a substantially L shape bent at a right angle, and protrudes toward the outside of the heating coil 100A. Therefore,
The loop-shaped conductor portion 141A is located diagonally above the heating conductor 110A, not directly above it.

The heating coil 100A is composed of a hollow square pipe, and is connected to a cooling liquid supply mechanism (not shown) so that the heating coil 100A itself is not overheated while the work W is being heated. It circulates.

Around the heating coil 100A, a cooling jacket (not shown) for injecting a cooling liquid for cooling the heated work W is installed in parallel with the heating conductor 110A.

Further, the heating coil 100A has a heating position for heating the work W by a vertical movement mechanism (not shown),
The work W can be moved up and down between a retracted position for cooling or carrying in and out. That is, if the coil 100A is located at the heating position, it is difficult to carry in and out the work W, and the cooling jacket
Since cooling liquid from (not shown) impinges on the heating coil 100A, it becomes difficult to perform efficient cooling. Therefore, the loading / unloading and cooling of the work W are performed when the heating coil 100A is in the retracted position. Of.

The other heating coil 100B has the same structure as the above-mentioned heating coil 100A. Here, the two heating coils 100A, 10A in the heating position
The center of the loop-shaped terminal portion 220 is located on the straight line L connecting the two centers of the loop-shaped conductor portions 141A and 141B of 0B. The moving mechanism 300 moves the current transformer 200 so that the center of the loop-shaped terminal portion 220 is always located on the straight line L.

These two heating coils 100A and 100B
Are installed so that the loop-shaped conductors 141A and 141B face each other. Further, in the current transformer 200, two heating coils 100A, both of which are in the heating position, are arranged so that the loop-shaped terminal portion 220 is located between the two loop-shaped conductor portions 141A and 141B.
It is installed such that the center of the loop-shaped terminal portion 220 is located on the straight line L connecting the two centers of the loop-shaped conductor portions 141A and 141B of 100B (see FIG. 1A).

Next, heating of the work W by the above-mentioned high frequency heating device will be described. First, one heating coil 100A is moved to the retracted position by the retracting mechanism, and the work W is supported by the pair of work centers 400. Then, the heating coil 100A is returned from the retracted position to the heating position.

The moving mechanism 300 for moving the current transformer 200
The heating coil 100A is moved to the loop-shaped terminal portion 220 of the output terminal 210 of the current transformer 200.
Faces the loop-shaped conductor portion 141A of the power supply terminal 140A of the heating coil 100A at a predetermined interval. That is, as shown in FIGS. 3 and 4, the loop-shaped terminal portion 220
Inner side surface 221 and the outer side surface 1 of the loop-shaped conductor portion 141A.
41a are opposed to each other with a predetermined gap. The cores 230 and 150 are provided by concentrating the generated magnetic force lines so that the heating coils 100A and 10A are
This is because the current is more efficiently flown by 0B. Also, FIG.
In the figure, the cores 230 and 150 are not shown for the sake of explanation.

In this state, power supply from the high frequency power source to the current transformer 200 is started. Then, the output terminal 21
Due to the magnetic field generated around the loop-shaped terminal portion 220 of 0, a current due to secondary induction flows in the loop-shaped conductor portion 141A, and further in the heating coil 100A. The work W is heated by the current due to the secondary induction.

When the predetermined heating of the work W is completed,
While stopping the power supply to the current transformer 200,
The moving mechanism 300 moves the current transformer 200 to the other heating coil 100B side. While the work W is being heated by the heating coil 100A,
The other heating coil 100B is moved up and down by an up-and-down moving mechanism (not shown) so that the next work W to be heated is set at a predetermined position.

The work W is heated by the other heating coil 100B in the same procedure as described above. Then, while the workpiece W is being heated by the heating coil 100B, the heating coil 100A is moved from the heating position to the retracted position by the vertical movement mechanism and receives the cooling liquid jet from the cooling jacket. After that, one of the work centers 400 evacuates and carries out the work W.

In this way, the two heating coils 100
A and 100B alternately heat and heat the work W.

In the first embodiment described above, the moving mechanism 300 is described as being composed of the guide 310, the ball screw member 320 and the driving source 330, but the present invention is not limited to this. Current transformer 200
It is sufficient that the loop-shaped terminal portion 220 can be moved between the loop-shaped conductor portions of the plurality of heating coils.

For example, instead of fixedly attaching the loop-shaped terminal portion 220 to the current transformer 200, as shown in FIG.
As shown in FIG.
And the current transformer 200 is fixed, and the loop-shaped terminal portion 22 is connected.
Only 0 may be moved. If only the loop-shaped terminal portion 220 is moved in this way,
A smaller drive source is required than when moving the entire current transformer 200, which is advantageous in terms of cost and space.

Next, a high frequency heating apparatus according to the second embodiment will be described with reference to FIG. In the high frequency heating apparatus according to the first embodiment, the two current coils 100A, 100 are moved by moving the current transformer 200.
Although the loop-shaped conductor portion 141A of B and the loop-shaped terminal portion 220 of the output terminal 210 are alternately opposed to each other, in the high-frequency heating device according to the second embodiment, the current transformer 200 is fixed. One heating coil 100A,
By moving 100B, two heating coils 1
The loop-shaped conductor portions 141A of 00A and 100B and the loop-shaped terminal portion 220 are alternately opposed to each other.

Two heating coils 10 similar to those described above
The basic structure in which the loop-shaped conductor portions 141A and 141B of 0A and 100B are arranged to face each other and the loop-shaped terminal portion 220 of the current transformer 200 is arranged between them is the high frequency heating according to the first embodiment. It is the same as the device.

However, in the high-frequency heating apparatus according to the second embodiment, two heating coils 100A, 1 facing each other are provided.
The distance between 00B needs to be set to be slightly larger than the length dimension of the work W to be heated.

Further, the moving mechanism 500 moves the two heating coils 100A and 100B, which is a difference from the high frequency heating apparatus according to the first embodiment. The moving mechanism 500 in the high-frequency heating device according to the second embodiment has two
The two heating coils 100A, 100B are moved in the left-right direction in FIG. 6 while keeping the distance between the heating coils 100A, 100B constant.

Specifically, the moving mechanism 500 includes a slider 510 to which the two heating coils 100A and 100B are attached with a constant space, and the slider 510.
And a drive source (not shown) that reciprocates in the left-right direction.

That is, according to this moving mechanism 500,
When the two heating coils 100A and 100B are moved to the leftmost side in FIG. 6, the heating coil 10 on the right side is moved.
The loop-shaped conductor portion 141A of 0A corresponds to the loop-shaped terminal portion 22.
0 (see FIG. 6A, but the loop-shaped conductor portion 141A is not shown because it is inside the loop-shaped terminal portion 220 in FIG. 6A) and moved to the rightmost side. In this case, the loop-shaped conductor portion 141B of the left heating coil 100B is adapted to enter the inside of the loop-shaped terminal portion 220 (see FIG. 6 (B), but in the figure, the loop-shaped conductor portion 141B is loop-shaped). Terminal part 2
Not shown because it is inside 20).

Moreover, as described above, the distance between the two heating coils 100A and 100B is the work W to be heated.
Since it is set to be slightly larger than the length dimension of
As shown in (A), when the work W is being heated by the heating coil 100A, the work W to be heated or heated by the heating coil 100B is located between the heating coil 100A and the heating coil 100B. Therefore, the work W can be easily carried in and out. Conversely, heating coil 1
When the work W is heated with 00B, the heating coil 1
The work W heated by 00A and the work W to be subsequently heated by the heating coil 100A can be easily carried in (see FIG. 6B).

For example, as the slider 510, 2
A side cover (indicated by a chain double-dashed line in FIG. 6) that connects the individual heating coils 100A and 100B from the side can be considered. The slider 510 includes two heating coils 1
It has a pair of cover portions 511 that respectively cover 00A and 100B from the side surface side, and a connecting portion 512 that connects the cover portions 511 at the upper end portion, and is formed in an inverted flat concave shape as a whole.

As described above, the slider 510 is formed in a reverse flat concave shape as a whole, so that the unheated work W can be easily carried in and out, the cooling liquid can be jetted to the heated work W, and the like. This is because Therefore, the connecting portion 512
Is set to be slightly larger than the work W.

Next, a third embodiment will be described with reference to FIG. Although the two heating coils 100A and 100B are used in the above-described first and second embodiments, the present invention is not limited to this.

For example, as shown in FIG. 7, one current transformer 200 and three heating coils 100A, 100B, 10 fed from this current transformer 200.
0C and each heating coil 100A, 100
B and 100C are high-frequency heating devices that sequentially heat the work W, and include a loop-shaped terminal portion 220 of the output terminal 210 of the current transformer 200 and the heating coils 100A and 100.
B, 100C power feeding conductors 140A, 140B, 140C
The moving mechanism 600 for relatively moving the loop-shaped conductor portions 141A, 141B, and 141C.

The moving mechanism 600 includes a rotary table 610 in which three heating coils 100A, 100B and 100C are radially arranged, a drive unit (not shown) for rotationally driving the rotary table 610, and the heating unit. Loop-shaped conductor portion 14 of the coils 100A, 100B, 100C
In order to make 1A, 141B, 141C face the loop-shaped terminal part 220 of the current transformer 200, it has an advancing / retreating moving means 620 for advancing / retreating each heating coil 100A, 100B, 100C on the rotary table 610.

Three heating coils 100A, 100B, 1
00C has the same configuration as the heating coil 100A and the like in the above-described first embodiment and the like, and thus detailed description thereof will be omitted.

The heating coils 100A, 100B, 1
The rotary table 610 that constitutes the moving mechanism 600 that moves 00C has three notches 611A at 120 ° intervals.
611B and 611C are provided. The rotary table 610 is connected to the drive shaft of a drive means (not shown) at the center of the rear surface thereof, as shown by an arrow α in FIG.
It is designed to be driven to rotate intermittently by 0 °.

On the other hand, the cutouts 611A, 611B, 6
11C includes a slider 6 that constitutes the advancing / retreating moving means 620.
21A, 621B, and 621C are slidably mounted between the heating position and the retracted position, respectively, and their tip ends are moved toward the center or the outer edge of the rotary table 610 by a driving unit (not shown) that constitutes the advancing / retreating moving unit 620. Then, as shown by an arrow β in FIG. 7, it moves back and forth.

The sliders 621A, 621B, 621
On the upper surface of C, each heating coil 100A, 100B, 10
0C is attached one by one. The heating coil 1
00A, 100B, and 100C are the loop-shaped conductors 1
41A, 141B, and 141C are radially arranged so as to face the center side of the rotary table 610.

A current transformer 200 is provided above the rotary table 610, and the loop-shaped terminal portion 220 of the current transformer 200 has a loop-shaped conductor portion 141A of each heating coil heating coil 100A, 100B, 100C. It is located near the center of the turntable 610 at the same height as 141B and 141C.

In the following description, each heating coil 10
The position where 0A, 100B, and 100C face the loop-shaped terminal portion 220 is the heating station position, the position rotated 120 ° clockwise in FIG. 7 from this heating station position is the cooling station position, and the cooling station position is the clockwise direction. The position rotated by 120 ° is defined as the loading / unloading station position.

Further, the sliders 621A, 621B,
The heating position of 621C means the sliders 621A and 621.
B and 621C are the positions closest to the center of the rotary table 610, and the sliders 621A and 62 at this position are located.
1B, 621C provided with heating coils 100A, 10
0B, 100C loop-shaped conductor portions 141A, 141B,
141C is adapted to enter the inside of the loop-shaped terminal portion 220 of the current transformer 200.

Further, the sliders 621A, 621B,
The retracted position of the 621C means the sliders 621A and 621.
B and 621C are the positions farthest from the center of the rotary table 610, and at this position, each heating coil 100
A, 100B, and 100C are configured to move further upward from above the sliders 621A, 621B, and 621C for cooling and carrying in / out the work W.

Next, the operation of the high frequency heating apparatus according to the third embodiment having the above-mentioned structure will be described. In addition,
In FIG. 7, the slider 621B is located at the heating station position, and the heating coil 10 provided on the slider 621B is
0B is in the retracted position. First, at the carry-in / out station position, the heating coil 100A on the slider 621A at the retracted position is moved upward to set the work W to be heated.

Next, the rotary table 610 is driven to rotate intermittently by 120 °, and the slider 621 on which the work W is set.
Move A to the heating station position. While performing the intermittent rotation, the heating coil 100A is moved downward so that the heating coil 100A can heat the work W.

When the rotary table 610 is intermittently rotated by 120 ° and reaches the heating station position, the slider 621A moves from the retracted position to the heating position. By this movement to the heating position, the loop-shaped conductor portion 141A of the heating coil 100A enters the inside of the loop-shaped terminal portion 220 as in the case shown in FIG.
The inner side surface 141a of 41A opposes the outer side surface 221 of the loop-shaped terminal part 220 with a predetermined space.

When a high-frequency current is supplied to the current transformer 200 in this state, the magnetic field generated around the loop-shaped terminal portion 220 causes a current to flow through the loop-shaped conductor portion 220, and thus the heating coil 100A, due to secondary induction, and the work W Heating is performed.

When the predetermined heating is completed, the slider 6
21A moves from the heating position to the retracted position. Then, the rotary table 610 is intermittently rotated by 120 °, and the slider 621A on which the heated work W is set is moved to the cooling station position. At this cooling station position, the heating coil 100A is raised, the cooling liquid is jetted from the cooling jacket (not shown) toward the work W, the work W is cooled, and the quenching is completed.

When the cooling of the work W is completed, the rotary table 610 is intermittently rotated by 120 ° and returns to the carry-in / out station position. At this carry-in / out station position, the work W that has been completely quenched is carried out, and then a new work W to be heated is set.

The three sliders 621A and 621
Each work, that is, the work W carry-in / out work, the work W heating work, and the work W cooling work are performed in parallel at the carry-in / out station position, the heating station position, and the cooling station position where B and 621C are located. Of course.

Although the three heating coils 100A, 100B and 100C are used in the third embodiment, the present invention is not limited to this, and there may be two heating coils or four or more heating coils. Of course, it can be applied to cases.

In addition, in the third embodiment, the three heating coils 1 arranged radially on the rotary table 610.
Although the loop-shaped terminal portion 220 of the current transformer 200 is provided on the center side of 00A, 100B, and 100C, the loop-shaped terminal portion 220 may be provided on the outside.
In this case, the heating coils 100A, 100B, 10
0C needs to be installed on the rotary table 610 (actually, on each slider 621A, 621B, 621C) so that the loop-shaped conductors 141A, 141B, 141C face outward.

When installed in this way, each slider 621A, 621B, 621C must move outward. Therefore, the following advantages occur. That is, if the sliders 621A, 621B, and 621C move toward the center as described above, in the unlikely event that two or more sliders move toward the center simultaneously due to some malfunction, the heating coil becomes space-like. There is a risk that the problem will interfere and work will stop. However, each slider 621A, 621
If B and 621C move outward,
Even if two or more sliders move at the same time, no interference occurs, and there is no risk of stopping the work.

[0061]

The high frequency heating apparatus according to the present invention has one current transformer and a plurality of heating coils fed from the current transformer, and each heating coil sequentially heats the work. The heating device includes a moving mechanism that relatively moves the output terminal of the current transformer and the power feeding conductor of each heating coil, and the moving mechanism includes the output terminal and the power feeding conductors of the plurality of heating coils. Are sequentially opposed to each other with a predetermined interval, and a current is passed through the heating coil by the secondary induction between the opposed output terminal and the feeding conductor.

Therefore, the power supply to the heating coil can be performed without contact with the current transformer.
No sparks are generated due to contact or connection failure does not occur. For this reason, the periodic maintenance or replacement work which is required in the conventional induction hardening apparatus becomes unnecessary, and the time loss and the cost increase accompanying the replacement work can be eliminated.

Further, the output terminal and the power feeding conductor have a loop-shaped portion, and one of them is fitted into the inside of the other so that they face each other at a predetermined interval. Therefore, the generated magnetic field lines can be used as electromotive force of the heating coil without leakage, which is very efficient.

Further, the moving mechanism is constructed so that at least one of the current transformer and each heating coil is moved so that the output terminal and the power feeding terminal face each other with a predetermined gap. Therefore, it is possible to optimally arrange each component and mechanism according to the installation location of the high-frequency heating device, the number of heating coils, and the like.

Further, the moving mechanism moves each heating coil, and only the feeding conductor of the heating coil in the heating position is made to face the output terminal of the current transformer. Therefore, it is possible to cool the heated work and to carry in and out the work with the heating coil that is not in the heating position, so that the work can be efficiently heated.

Further, in the moving mechanism, a rotary table in which a plurality of heating coils are radially arranged, driving means for rotating the rotary table, and a power supply terminal of the heating coil facing an output terminal of the current transformer. In order to do so, each heating coil has an advancing / retreating means for advancing / retreating on the rotary table. With this configuration, 3
A suitable configuration can be provided when having more than one heating coil.

[Brief description of drawings]

FIG. 1 is a schematic side view showing the configuration of a high-frequency heating device according to a first embodiment of the present invention.

FIG. 2 is a schematic perspective view of a heating coil used in this high-frequency heating device.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 1 showing a state in which an output terminal of a current transformer used in this high frequency heating device and a power supply terminal of a heating coil face each other.

FIG. 4 is a schematic cross-sectional view showing a state in which an output terminal of a current transformer used in this high-frequency heating device and a power supply terminal of a heating coil face each other.

FIG. 5 is a schematic side view showing the configuration of a high-frequency heating device using another moving mechanism.

FIG. 6 is a schematic side view showing a configuration of a high-frequency heating device according to a second embodiment of the present invention.

FIG. 7 is a schematic plan view showing the configuration of a high-frequency heating device according to a third embodiment of the present invention.

8A and 8B are diagrams showing a schematic configuration of a conventional high-frequency heating apparatus of this type, wherein FIG. 8A is a schematic plan view and FIG. 8B is a schematic side view.

[Explanation of symbols]

 100A, 100B heating coil 200 current transformer 210 output terminal 300 moving mechanism W work

Claims (5)

[Claims] 1. A high frequency heating apparatus having one current transformer and a plurality of heating coils fed from the current transformer, wherein each heating coil sequentially heats a workpiece, and an output terminal of the current transformer. And a moving mechanism for relatively moving the feeding conductor of each heating coil, the moving mechanism sequentially opposes the output terminal and the feeding conductors of the plurality of heating coils at a predetermined interval. A high-frequency heating device, characterized in that a current is caused to flow through a heating coil by secondary induction between an output terminal and a power supply conductor which face each other. 2. The output terminal and the power supply conductor have a loop-shaped portion, and one of them is fitted into the inside of the other so that they face each other with a predetermined interval. Item 1. The high frequency heating device according to item 1. 3. The moving mechanism, wherein at least one of the current transformer and each heating coil is moved so that the output terminal and the power feeding terminal are opposed to each other at a predetermined interval. High frequency heating device. 4. The moving mechanism moves each heating coil, and the feeding conductor of only the heating coil at the heating position is opposed to the output terminal of the current transformer. The high frequency heating device according to claim 1. 5. The moving mechanism comprises a rotary table in which a plurality of heating coils are radially arranged, drive means for rotating the rotary table, and a power supply terminal of the heating coil facing an output terminal of a current transformer. In order to do so, each heating coil is provided with an advancing / retreating moving means for advancing / retreating on the rotary table.
The high-frequency heating device described.