JPH04355093A - Inductive heating device - Google Patents

Abstract

PURPOSE:To obtain an inductive heating device excellent in uniform heating power of a large area while capable of suppressing a temperature rise of an inductive heating coil and to lower cost. CONSTITUTION:A groove 4 is provided on one side surface of a coil frame 1 consisting of an insulating material having heat resistance and not being heated by an electromagnetic inducting action separated by a partition 5 and an induced heating coil 6 is arranged inside this groove 4. A heating device having high heating efficiency and able to suppress a temperature rise of an inductive heating coil and to lower cost.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction heating device using electromagnetic induction heating means.

0002

2. Description of the Related Art FIG. 14 is a schematic diagram of a general electromagnetic induction cooking device. In the figure, 41 is a cooker case, 4
2 is a coil support provided in the case 41, on the upper surface of which adjacent conductors are tightly wound (hereinafter referred to as close contact).
An induction heating coil 43 (hereinafter simply referred to as a coil) is provided. A plurality of ferrite plates 44 are radially attached to the lower surface of the coil support 42 and are used to increase the inductance of the coil 43. 45 is made of an insulating material that has heat resistance and transmits electromagnetic waves, such as glass ceramics, and is attached to the upper opening of the case 41; The heat insulating material 47 is a cooking pot made of iron-based material that generates heat by electromagnetic induction. Generally, the outer diameter of the cooking pot 47 is about 200 mm, and the outer diameter of the coil 43 is smaller than this, about 180 mm.
The number of turns of 3 is 18 to 20, and the inductance is 60 to 80.
μH.

[0003] In the above heating cooker, for example, a cooking pot 47 containing a food to be cooked containing an appropriate amount of water is placed on a pot holder 45, and a coil 43 receives a frequency of 20 to 50 KHz.
When a high frequency current of about
As shown in Fig. 5, a heating pattern with two peaks generates a ring shape around each peak and heats up.
Cooked. In addition, the vertical axis of FIG. 15 shows the temperature difference of the cooking pot 47, and the difference t is 80 to 100 degrees.

[0004] In this case, if there is no water in the cooking pot 47, the temperature at the bottom of the pot will rise to 300°C, so the pot holder 45 is made of a heat-resistant inorganic material as described above. . In addition, in order to protect the coil 43 from high heat in this way, it is necessary to separate the coil 43 and the cooking pot 47 to a certain extent (for example, 8 to 10 mm), and for this reason, it is necessary to increase the degree of coupling between the two. A plurality of ferrite plates 44 are attached to the coil support 42 to improve thermal efficiency.

[0005] Conventional heating cookers heat the food using a heating pattern as shown in FIG. 15, which results in poor heating efficiency and uneven heating, which prevents delicious cooking. In addition, expensive ferrite must be used to increase the degree of coupling and improve thermal efficiency, and furthermore, when used for high-temperature heating, the high self-heating of the coil 43 causes deterioration of the insulation between adjacent conductors. There are many other problems.

In order to solve this problem, a cooking device as shown in FIG.
(See Publication No. 681). This cooking device has a pot mounting base 45a shaped like a deep pot, uses a deep pot-shaped cooking pot 47a, and has a tightly wound first coil 33a arranged opposite to the bottom of the cooking pot 47a. At the same time, a closely wound second coil 43b is arranged opposite to the lower part of the side wall of the cooking pot 47a, and both are connected in series. In addition, 42 is a coil support body, and 44 is a ferrite plate attached to the lower surface of the coil support body 42.

In the above cooking device, the cooking pot 47a generates heat not only at the bottom but also at the side wall, so the heat capacity of the cooking pot 47a can be increased compared to the heating cooker explained in FIG. Uniformity can be improved.

[0008]

[Problems to be Solved by the Invention] In the above cooker, the coils 43a and 43b are large in size in order to generate heat over a wide range from the bottom to the side wall of the cooking pot 47a, resulting in a large inductance and Oscillation cannot be made within the occupied frequency band of 20 to 100 KHz defined by the Ministry of Health. For this reason, the coil is connected to the first coil 43a.
The coil is divided into a second coil 43b, but the split coil is more complicated to manufacture than a simple close-contact coil, and the manufacturing process is increased, and ferrite 44 is used to increase the inductance. Therefore, an increase in costs is unavoidable.

Furthermore, since this cooking device has a heating pattern with four peaks, the temperature difference of the cooking pot 47a (
(see FIG. 15) and the heating unevenness is slightly improved, but many problems still remain, such as the non-uniform heating.

The present invention has been made to solve the above-mentioned problems, and aims to provide an induction heating device that has excellent uniform heating performance over a large area, can suppress the temperature rise of the coil, and can further reduce costs. That is.

[0011]

[Means for Solving the Problems] The induction heating device according to the present invention has a coil frame made of an insulating material that is heat resistant and does not generate heat due to electromagnetic induction, and a groove is provided on one surface of the coil frame with a partition wall in between. An induction heating coil is placed inside.

In the above induction heating device, the induction heating coil is press-fitted into the coil frame, or the induction heating coil is provided in an area wider than the bottom of the object to be heated, and furthermore, the coil frame is placed on a mounting table for the object to be heated. It is also used as

[0013]

[Operation] The object to be heated is placed on the coil frame on which the induction heating coil is arranged, or placed close to the coil frame, and a high frequency current is supplied to the induction heating coil. As a result, the object to be heated generates heat due to the electromagnetic induction action with the induction heating coil.

[0014]

[Embodiment] FIG. 1 schematically shows an embodiment of the present invention, with a cross-sectional view,
FIG. 2 is a bottom view thereof. In the figure, numeral 1 denotes a pot holder that also serves as a coil winding frame, and 6 denotes a coil provided on the pot holder 1. The pot holder 1 is made of a heat-resistant material such as heat-resistant plastic or ceramics and is transparent to electromagnetic waves, that is, an insulating material that does not generate heat due to electromagnetic induction, and has a concave portion 2 and is approximately dish-shaped. As shown in FIGS. 2 and 3, a spiral groove 4 is provided on the lower surface of the bottom portion with a partition wall 5 in between. In the embodiment, the width d1 of this groove is set to about 90% of the diameter d of the coil 6, the width w of the partition wall 5 is set to about 70% of the diameter d of the coil 6, and the coil 6 is deformed into a slightly elliptical shape. It was press-fitted into groove 4. Note that the width d1 of the groove 4 may be formed to be approximately equal to or slightly larger than the diameter d of the coil 6, and the coil 6 may be installed and fixed within the groove 4 using a heat-resistant adhesive. The coil 6 is arranged from near the center of the pot holder 2 to outside the lower projected area of a cooking pot 7, which will be described later.

[0015] As described above, the coil 6 according to the present invention is fixed in the groove 4 across the partition wall, and since the pot holder 1 is made of an insulating material, special insulation treatment is applied between the coils 6. There is no need for this, and adjacent conductors are separated from each other to form a so-called sparsely wound coil. According to the regulations of the Ministry of Posts and Telecommunications, the occupied frequency band is 20 to 100 KHz as mentioned above, so in this embodiment, the number of turns is 18 to 2 so that the inductance of the coil 6 resonates at 60 to 80 μH.
Adjust the wire diameter and pitch so that it is 0 times, and increase the coil diameter by 3
It was set to 0 cm. 7 is a cooking pot housed in the recess 3 of the coil frame 3, and is made of a magnetic material with high resistivity and high relative permeability;
That is, it is made of a material that generates heat by electromagnetic induction.

Reference numeral 10 denotes a driving device for the coil 6, and a circuit of an embodiment thereof is shown in FIG. 11 is a full-wave rectifier circuit, 12 is a smoothing capacitor connected to its output side, 6 is a coil, 13
is a switching element 14 connected in series with the coil 6;
is a resonant capacitor connected in parallel to the coil 6, 15 is a regenerative diode connected in parallel to the switching element 13, and 16 is a regenerative diode connected in parallel to the switching element 1 by a frequency control signal.
3, a variable frequency controller that outputs a variable frequency; 17;
is the power plug.

In the drive circuit as described above, an alternating current from a power source is converted to direct current by a full-wave rectifier circuit 11, smoothed by a smoothing capacitor 12, and applied to a resonant circuit consisting of a coil 6 and a resonant capacitor 14. . On the other hand, the output of the variable frequency controller 16 is applied to the switching element 13 to turn it on and off, causing a high frequency current to flow through the coil 6. The frequency of the high frequency current flowing through the coil 6 is controlled by a variable frequency controller 16.

Next, the operation of the present invention constructed as described above will be explained. First, food to be cooked is placed in the cooking pot 7 and set on the pot holder 1. Then, the power switch is turned on and a high frequency current of about 20 to 50 KHz is caused to flow through the coil 6. Magnetic flux is generated by the excitation of the coil 6, and alternating eddy currents are generated in the cooking pot 7 due to electromagnetic induction.
generates heat to 200-260°C to heat and cook the food. During this time, the temperature of the cooking pot 7 is detected by a temperature sensor (not shown), and the variable frequency controller 16 is controlled based on the detection result to control the frequency of the high frequency current flowing through the coil 10. The heat generation of the cooking pot 7 and therefore the heat level can be adjusted.

In the present invention configured as described above,
Since the coils 6 are loosely wound and arranged at approximately equal intervals from the vicinity of the center of the pot holder 2 to the area reaching the lower projected area of the cooking pot 7, the cooking pot 7 is evenly wound as shown in FIG. The heating efficiency is increased by generating heat, and the food to be cooked in the cooking pot 7 can be heated uniformly. In addition, in FIG. 5, the vertical axis represents the temperature difference of the cooking pot 7, and in this example, the difference t is 30 to 40 degrees.

In the above description, the coil 6 is arranged in a spiral shape, but it may be arranged in a rectangular or other arbitrary pattern. In addition, although an example was shown in which the coil 6 was provided on the bottom surface of the pot mounting table 1, the coil 6 was arranged on the top surface of the pot mounting table 1,
The cooking pot 7 may be placed through an insulating plate through which electromagnetic waves pass.

Furthermore, although the case where the coil 6 is placed directly on the pot holder 1 has been shown, a coil winding frame may be separately provided and attached to the pot holder 1. In this case, the coil 6 may be installed directly on the pot holder 1. 1 may be made of a material that generates heat by electromagnetic induction, and a cooking pot made of a non-magnetic material may be placed on this to heat it.

FIG. 6 is a schematic diagram of an embodiment in which the present invention is applied to a rice cooker, and FIG. 7 is a bottom view thereof. In the figure, 1a is a pot mounting stand that also serves as a deep pot-shaped coil winding frame whose bottom and side walls are connected by an inclined surface or an arcuate surface, 7a is a pot mounting stand with an inward protrusion 8 provided at the center of the bottom. In the cooking pot housed in the cooking pot 1a, the materials constituting the pot mounting stand 1a and the cooking pot 7a are the same as those in the embodiment shown in FIG.

[0023] Grooves 4 are provided on the outer surface of the pan mounting table 1a from the bottom to the side wall, with partition walls 5 interposed therebetween, and the spacing between the grooves 4, and therefore the width w of the partition wall 5, differs depending on the location. That is, the vicinity of the center of the bottom is the cooking pot 7a.
A protrusion 8 provided at the bottom of the cooking pot 7a and the coil 6
Since the distance between the partition wall 5 and
The width w2 of the partition wall 5 is increased slightly and the coil 6 is wound slightly sparsely, and the width w3 of the partition wall 5 is increased and the coil 6 is wound loosely in the part extending from near the outer periphery of the bottom to the outer wall via the slope.
The width of the partition wall 5 was made w1 < w2 < w3, and the coil 6 was connected to the pot mounting table 1 by the same means as in the embodiment shown in FIGS. 1 to 3.
It was arranged in the groove 4 of a.

In this embodiment configured as described above,
Put rice and an appropriate amount of water in the cooking pot 7a, set it on the pot stand 1a, turn on the power, and set the coil 6 to 20 to 50 KHz.
When a high-frequency current is applied to the cooking pot 7a, the cooking pot 7a rapidly generates heat, heats the water inside, and cooks rice. During this time, the temperature of the cooking pot 7a is detected by a temperature sensor (not shown), and based on this result, the frequency of the high-frequency current flowing through the coil 6 is controlled to adjust the heat generation of the cooking pot 7a, and therefore the heat level. .

In this embodiment, the coil 6 is arranged up to the vicinity of the side wall of the cooking pot 7a, and the distribution amount of the coil 6 can be set according to the shape of the cooking pot 7a. Since a three-dimensional heating design is also possible, delicious rice can be cooked even with a thin and inexpensive cooking pot with a small heat capacity.

FIG. 8 is a schematic diagram of an embodiment in which the present invention is applied to a microwave oven. In the figure, 19 is the heating chamber 18
The inner box is made of a magnetic material with high resistivity and high relative magnetic permeability, that is, a material that generates heat by electromagnetic induction, and its inner surface is treated to reflect microwaves. The inner box 19 may have a bottom plate made entirely or partially of a material that generates heat due to electromagnetic induction, and the other portions may be made of a material that is heat resistant and does not generate heat due to electromagnetic induction.

1b is a coil frame disposed under the inner box 19, which is made of the same material as the pot holder 1 of the embodiment shown in FIG. coil 6
is installed. 20 is a planar mica heater provided above the inner box 19; 21 is a magnetron attached to the inner box 19; microwaves emitted from the magnetron 21 are sent to the heating chamber 18 through an opening 19a provided in the inner box 19;
Guided within. In this embodiment, the turntable on which the cooking container and the like are placed is omitted, and the cooking container and the like are placed directly on the bottom plate of the inner box 19, but the coil frame 1b and the inner box are A turntable may be attached in the heating chamber 18 to a shaft passing through the bottom plate 19, and this shaft may be rotated by a motor.

FIG. 9 is a circuit diagram showing an embodiment of the drive circuit for the magnetron 21 and the coil 6, where 11 is a full-wave rectifier circuit including an AC-DC converter and a switching circuit, 22 is an oscillator for the magnetron 21, and 6 is an oscillator. A coil is connected in parallel to 22, and 23 is a changeover switch.

In the drive circuit as described above, the power supply current supplied to the full-wave rectifier circuit 11 is converted into a high-frequency current. Now, when the changeover switch 23 is turned to the a side, the high frequency current is supplied to the oscillator 22, which oscillates and generates the magnetron 21.
Microwaves are emitted from the heating chamber 18 to the heating chamber 18. Further, when the changeover switch 23 is turned to the b side, a high frequency current flows through the induction heating coil 6, causing the inner box 19 disposed close to the induction heating coil 6 to generate heat due to electromagnetic induction. If a third contact c is provided and connected to the oscillator 22 and the coil 6 as shown by the broken line, both the magnetron 21 and the coil 6 can be operated simultaneously by turning the changeover switch 23 to the c side.

Next, the operation of the present invention constructed as described above will be explained. First, the food to be cooked is placed in a cooking container and housed in the heating chamber 18 either directly or placed on a turntable. When using this heating cooker as an oven range, set the selector switch 23 to the b side and set the coil 6 to the
A high frequency current is passed at about ~50KHz. The bottom plate of the inner box 19 rapidly generates heat to raise the temperature of the heating chamber 18 by radiation and air convection, thereby heating and cooking the food in the cooking container. In addition, if necessary, the mica heater 20 is energized,
If the food to be cooked is heated by the radiant heat or air convection, the cooking time can be further shortened.

Next, when using it as a microwave oven,
If the changeover switch 23 is set to the a side, the magnetron 21
Microwaves are outputted into the heating chamber 18 to heat and cook the food. In this case, the mica heater 20 may be energized to promote heating, or depending on the type of food to be cooked, the selector switch 23 may be set to the c side so that both the magnetron 21 and the coil 6 heat the food. .

As described above, in this embodiment, the magnetron 21 and the coil 6 can share the same power source, thereby reducing the cost, and since the bottom of the heating chamber 18 is directly heated, the heating efficiency is high. Thermal effects on others can be significantly reduced.

FIG. 10 is a schematic diagram of an embodiment in which the present invention is applied to a cordless iron, and FIG. 11 is a bottom view thereof. In the figure, 1c is a coil frame provided on a substrate 24 via an insulating plate 25, and is made of the same material as in each of the above-mentioned embodiments. It is set up. 26 is a wire mesh placed on the coil frame 1c, and this wire mesh 26 is provided to increase the inductance of the coil 6, and is made of a magnetic material with high resistivity and high relative permeability, such as iron or stainless steel. That is, it is made of a wire that generates heat due to electromagnetic induction. Reference numeral 28 denotes an iron, and at least the bottom portion thereof is made of a magnetic material with high resistivity and high relative permeability, that is, a material that generates heat by electromagnetic induction. 29 is a cloth to be ironed. In addition, the substrate 24, the insulating plate 25, the coil frame 1c, the wire mesh 2
6 is covered with a cover 27 and constitutes an ironing board 30.

Next, the operation of the embodiment configured as described above will be explained. First, the power is turned on and a high frequency current of about 5 A is passed through the coil 6 to heat the wire mesh 26 to an appropriate temperature by electromagnetic induction and maintain it in a standby state. Next, place the cloth 29 to be ironed on the ironing board 30,
An iron 28 is placed on top of it. When the iron 28 is placed on the coil 6, a high frequency current of about 12 to 13 A and 20 to 25 KHz is supplied to the coil 6 due to the change in inductance, and the bottom of the iron 28 is caused by electromagnetic induction with the bottom of the iron 28. generates heat, thereby ironing the cloth 29.

When the iron 28 is taken down from the ironing board 30 to sort or change cloth or to take a rest, a high frequency current of about 5 A flows through the coil 6 again, causing the wire mesh 26 to generate heat and keeping the ironing board 30 at an appropriate temperature. Therefore, there is no need to preheat the iron 28, and the user can immediately move on to the next ironing task.

In the above description, one coil 6 is provided on almost the entire surface of the ironing board 30, but the ironing board 30 may be provided with two or more coils. Further, the shape of the coil 6 is not limited to a square,
Oval, circular or other suitable patterns can be used. Furthermore, conventionally, it was not possible to pass current through the coil when the ironing board was under no load, but in this embodiment, a wire mesh 26 is placed above the coil 6 to increase the inductance of the coil 6, so that when the ironing board is under no load, the inductance of the coil 6 is increased. Also coil 6
A current can be passed through the metal mesh 26 to generate heat to maintain the ironing board 30 at an appropriate temperature.

In this embodiment as described above, since the iron-based wire mesh 26 is provided on the entire upper surface of the coil 6, a certain amount of current can be passed through the coil 6 without placing the iron 28 on it, and the ironing board 30 can be preheated. In addition, conventionally, the ironing board 30 was constructed by providing a plurality of closely wound small coils (for example, 4 to 6), but according to this embodiment, the ironing board can be constructed with a single loosely wound coil, which reduces the weight. It can be significantly reduced. Furthermore, since both sides of the cloth 29 to be ironed are heated by both the iron 28 and the ironing board 30, the ironing effect can be further enhanced.

FIG. 12 is a sectional view of an embodiment in which the present invention is applied to a hot air heater. In the figure, 31 is an outer case with a substantially U-shaped cross section, and is made of an insulating material that is heat-resistant and transmits electromagnetic waves, such as heat-resistant plastic, that is, an insulating material that does not generate heat due to electromagnetic induction. A large number of air intake ports 31a are provided.

Reference numeral 1d designates a coil frame disposed within the outer case 1, and a coil 6 is disposed within a groove 4 provided in the coil frame as in each of the previously described embodiments. Reference numeral 32 indicates a motor attached to approximately the center of the coil frame 1d, and reference numeral 33 indicates an air intake port provided in the coil frame 1d around the motor 32. 3
An inner case 4 is provided on the front side of the coil frame 1d and is fixed to the outer case 31. Like the outer case 31, it is made of an insulating material that is heat resistant and does not generate heat due to electromagnetic induction. A hole is provided through which the 32 output shafts are inserted. 34a is a plurality of ventilation holes provided around the above hole.

35 is the motor 32 inside the inner case 34.
As shown in Fig. 13, this is a blower turbo fan fixed to the output shaft of a disk 3 made of a magnetic material with high resistivity and high relative permeability, that is, a material that generates heat by electromagnetic induction.
6, and a plurality of vanes 37 made of a light metal material such as aluminum, fixed radially to the surface of a disc 36, and fixed to the output shaft of the motor 32. Note that 38 is a guard plate provided on the front surface of the outer case 31, and there are a plurality of air intake holes 38a near the center.
is provided, and a hot air outlet 40 is formed around it.

Next, the operation of the present invention constructed as described above will be explained. First, turn on the power and apply 20~50 to coil 6.
A high frequency current of approximately KHz is passed. Magnetic flux is generated by excitation of the coil, and the blower turbo fan 35 is generated by electromagnetic induction.
An alternating overcurrent occurs in the disk 36, causing the disk 36 to rapidly generate heat and heat the vane plate 37 attached thereto. On the other hand, when the power is turned on, the motor 32 is driven, and a blower turbo fan 35 fixed to the output shaft of the motor 32 is driven.
Rotate.

When the blower turbo fan 35 rotates, the area around it becomes negative pressure, so the air at the rear of the outer case 1 flows from the air intake port 31a to the ventilation hole 33 of the coil frame 1d to the inner case 3.
The air is guided between the inner case 34 and the blower turbo fan 35 through the ventilation hole 34a of No. 4, and cools the disk 36 while moving along the disk 36, and is heated by absorbing the heat of the disk 36. , and is blown out from the hot air outlet 40 as warm air. In addition, the air in front of the outer case 31 is removed from the guard plate 3
The air is taken in between the guard plate 38 and the blower turbo fan 35 through the air intake hole 38a of No. 8, and cools the disk 36 and the blade plate 37 while moving along the disk 36, and absorbs the heat. It is heated, becomes hot air, and is blown out from the hot air outlet 40.

In this embodiment, since the disk 36 is uniformly heated by the loosely wound coil 6, there is no risk of the disk 36 being deformed, the heat dissipation efficiency is high, and the small and high power hot air You can get a heater.

[0044]

[Effects of the Invention] As described in detail above, the present invention constitutes an induction heating device using loosely wound coils, so it is possible to heat a large area while ensuring an appropriate inductance value, and to achieve uniform heating. Any heating pattern can be obtained including settings. Furthermore, even in a heating cooker (hot plate) that requires high temperatures, since the loosely wound coil prevents the coil from being affected by self-heating and mutual heating, it is possible to reduce the rise in coil temperature.

Furthermore, since the increase in coil temperature can be reduced, the distance between the heated body and the coil can be made shorter than before, and the degree of coupling increases, making it possible to improve heating efficiency by about 10%. Furthermore, since the ferrite can be omitted due to the increased degree of bonding, it has become possible to use inexpensive heat-resistant molded plastic in place of the expensive glass ceramics that were conventionally disposed between the coil and the heated body.

In addition, when manufacturing the coil, it is possible to adopt a method of pushing the conductor into a groove provided in the coil frame, so a tightly wound coil can be manufactured using a separate method as in the past, and then hardened with a thermosetting adhesive. There is no need for a complicated process such as bonding the coil to the support, and it can be easily manufactured using a relatively simple automatic machine, and the part into which the conductor is pressed becomes the structure of the product itself. , manufacturing efficiency is extremely high and costs can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view schematically showing an embodiment of the present invention.

FIG. 2 is a bottom view of FIG. 1;

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a circuit diagram of an embodiment of a coil drive circuit.

FIG. 5 is a schematic diagram showing a heating pattern of this example.

FIG. 6 is a schematic diagram of an embodiment in which the present invention is applied to a rice cooker.

FIG. 7 is a bottom view of FIG. 6;

FIG. 8 is a schematic diagram of an embodiment in which the present invention is applied to a microwave oven.

FIG. 9 is a circuit diagram of an embodiment of the drive circuit of FIG. 8;

FIG. 10 is a schematic diagram of an embodiment in which the present invention is applied to a cordless iron.

FIG. 11 is a bottom view of FIG. 10;

FIG. 12 is a schematic diagram of an embodiment in which the present invention is applied to a hot air heater.

13 is a plan view of the blower turbo fan of FIG. 12. FIG.

FIG. 14 is a schematic diagram of an example of a conventional heating cooker.

15 is a schematic diagram showing the heating pattern of FIG. 14. FIG.

FIG. 16 is a schematic diagram of another example of a conventional cooking device.

[Explanation of symbols]

1,1a　Pot stand 1b, 1c, 1d Coil frame 4 groove 5 Partition wall 6 Induction heating coil 7 Cooking pot 11 Full wave rectifier circuit 13 Switching element 14 Resonance capacitor 16 Variable frequency controller 18 Heating chamber 21 Magnetron 22 Oscillator 23 Selector switch 26 Wire mesh 28 Iron 32 Motor 35　Blower turbo fan 36 Disc

Claims (4)

[Claims] Claim 1: In a heating device using electromagnetic induction heating means, a coil frame made of an insulating material that is heat resistant and does not generate heat due to electromagnetic induction has a groove separated by a partition wall on one side of the coil frame, and a groove is provided in the groove. An induction heating device characterized by being equipped with an induction heating coil. 2. The induction heating device according to claim 1, wherein the induction heating coil is press-fitted into a groove in the coil frame. 3. The induction heating device according to claim 1, wherein the induction heating coil is provided in an area wider than the bottom of the object to be heated. 4. The induction heating apparatus according to claim 1, wherein the coil frame also serves as a mounting table for the object to be heated.