JP2011124115A - Heating coil for induction heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce heating loss and to improve productivity of a heating coil for an induction heating device. <P>SOLUTION: A magnetic body 7 is fixed to a belt-like insulator 6 by an adhesive 8 to form a spacer 9, and an electric conductor 5 is arranged in a spiral shape with a gap between turns. Putting the spacer 9 in the gap and fixing the electric conductor 5 and the spacer by adhesives 10a, 10b makes it easy to form a spiral shape with a bent part, and an arrangement of putting both the electric conductor and the spacer in the spiral area makes it easy to arrange the magnetic body between the turns of the electric conductor. When arranging only a space part without the magnetic body between the turns of the electric conductor, it is easily arranged by simply inserting a spacer between turns of the electric conductor, if the spacer is formed by excluding the magnetic body only for that part when the spacer is formed. This leads to excellent productivity, and hence, improvement of the heating coil cooling performance by reducing high frequency resistance of the heating coil electric conductor and reducing the heating loss. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an induction heating apparatus configured to easily manufacture a heating coil with reduced loss and improved cooling performance.

  Conventionally, this kind of heating coil for induction heating devices has a magnetic material inserted between spiral electric conductors (see, for example, Patent Document 1).

  FIG. 9 shows a conventional heating coil for induction heating apparatus described in Patent Document 1. In FIG. As shown in FIG. 9, the electric conductor 41 is formed in a spiral shape, and the magnetic body 42 is inserted between the electric conductors 41 on the inner periphery of the electric conductor 41. Further, a space is provided between the electric conductors 41 in the middle and outer peripheral portions.

  FIG. 10 is a schematic view of the electromagnetic environment around adjacent coils.

  Generally, when a current flows in parallel to adjacent electrical conductors, a proximity effect is generated in which the current is less likely to flow due to the influence of a magnetic field generated from each electrical conductor. For example, FIG. 10 shows a coil wire 43 as an electric conductor and a magnetic flux 44 generated from the coil wire.

  It is assumed that a current flows through the coil wire 43 in FIG. The distribution of the current in the coil wire 43 is biased in a direction away from the adjacent coil wire due to the magnetic flux 44 generated from the adjacent coil wires.

  The shading of the color of the coil wire 43 in FIG. 10 represents the current density, and the dark portion indicates that the current density is high. A series of phenomena that cause this current distribution bias is generally called a proximity effect. Due to this proximity effect, the resistance of the heating coil (especially, the high frequency resistance when a high frequency current is passed) increases, and the heat loss of the heating coil increases.

  Conventionally, in order to solve this problem, by inserting a magnetic body 42 between the turns of the electric conductor 41 as shown in FIG. 9, a magnetic field is generated when a current flows through the electric conductor 1. However, the proximity effect can be reduced by the magnetic flux acting on the magnetic body 42 provided between the turns of the electric conductor 41. As a result, the resistance of the heating coil is reduced and the heating coil is reduced. The heat loss of is reduced.

JP 2002-43044 A

  However, the conventional configuration has a problem that it is difficult to manufacture because the magnetic body 42 is inserted between the turns of the spiral electric conductor 41. In particular, it was difficult to process the magnetic body 42 into a spiral shape and insert it between the electrical conductors 41.

For example, it has been extremely difficult to insert between the spiral electric conductors 41 using the powdery magnetic body 42. In addition, it is difficult to maintain the dimension of the portion without the magnetic body 42, that is, only the space between the electric conductors 41 at a predetermined value. Furthermore, the magnetic body 42 is basically conductive, and it has been difficult to ensure insulation between the electric conductors 41.

  An object of the present invention is to solve the conventional problems described above, and to provide a heating coil for an induction heating apparatus that improves productivity, reduces heat loss, and improves the cooling performance of the heating coil. To do.

  In order to solve the above-described conventional problems, the heating coil for an induction heating device according to the present invention is provided with a spacer having a magnetic material fixed on at least one surface of a strip-shaped insulator, and is provided in a gap between turns of a spiral electric conductor. An insulator is provided.

  As a result, the productivity of inserting the magnetic material between the turns of the spiral electric conductor is greatly improved for the following four reasons. First, by fixing the magnetic body to the strip-shaped insulator in advance, it becomes easy to form a spiral shape having a curved portion even with respect to various forms of magnetic bodies (for example, forms such as powder). Second, if both the electric conductor and the spacer are spirally wound, a magnetic material can be easily provided between the turns of the electric conductor. Thirdly, even when creating a space-only part with no magnetic material between the turns of the electrical conductor, if only that part is formed by removing the magnetic material in advance when forming the spacer, a spacer is inserted between the turns of the electrical conductor. It can be easily formed by just doing. Fourth, the spacer is made of an insulator, and the insulation between the turns of the electric conductor can be easily secured.

  The heating coil for an induction heating device of the present invention can form a magnetic body easily at a predetermined location between turns of a spiral electric conductor, and is extremely excellent in productivity. Of course, by forming a magnetic body between the turns of the electrical conductor, reducing the proximity effect that occurs between the turns of the electrical conductor, lowering the high-frequency resistance of the electrical conductor of the heating coil and reducing the heat loss, the result As a result, the cooling performance of the heating coil can be improved.

Sectional drawing of the heating coil for induction heating apparatus in Embodiment 1 of this invention Sectional drawing of the heating coil for induction heating apparatuses in Embodiment 2 of this invention The principal part perspective view of the heating coil for induction heating apparatuses in Embodiment 2 of this invention Sectional drawing of the heating coil for induction heating apparatuses in Embodiment 3 of this invention The principal part perspective view of the heating coil for induction heating apparatuses in Embodiment 3 of this invention Sectional drawing of the heating coil for induction heating apparatuses in Embodiment 4 of this invention The principal part perspective view of the heating coil for induction heating apparatuses in Embodiment 4 of this invention Sectional drawing of the form which used the heating coil for induction heating apparatuses in Embodiment 5 of this invention for the induction heating cooking appliance. Sectional view of a conventional heating coil for induction heating devices Schematic diagram of electromagnetic environment around neighboring coils

  According to a first aspect of the present invention, by providing a spacer having a magnetic material fixed on at least one surface of a strip-shaped insulator, forming an electric conductor in a spiral shape with a gap, and providing a spacer in a gap between turns of the electric conductor Since the spacer is formed by fixing the magnetic material to the strip-shaped insulator in advance, the magnetic material that is difficult to process in a spiral shape can be formed in a spiral shape with the magnetic material held in the spacer. A magnetic body can be easily formed between the turns of the electric conductor by the process of winding the conductor and the spacer together, and a heating coil for an induction heating apparatus with excellent productivity can be provided.

  In the second invention, in particular, in the first invention, by providing the spacer with the magnetic body fixed inside the two strip-shaped insulators, the magnetic body is sandwiched between the insulators from both sides. It is possible to securely hold the magnetic body. Also, the insulation between the turns of the electric conductor can be ensured because the magnetic body is sandwiched between the two strip-shaped insulators.

  In the third invention, in particular, at least a part of the spacer of the first or second invention has a configuration in which a magnetic material is not provided between the turns of the electric conductor by making a place where no magnetic material is provided, so that only a space is desired. Easy to configure. That is, it can be easily produced by forming a space between the turns of the spiral electric conductor while ensuring a predetermined dimension and providing a magnetic body at a desired position between the turns.

  According to a fourth aspect of the present invention, in particular, in any one of the first to third aspects, the magnetic material is provided with a portion having a large thickness and a portion having a small thickness, or a portion having a magnetic material and a portion having no magnetic material. And the spacer can be easily formed in a spiral shape.

  In particular, the fifth aspect of the invention provides a powdery magnetic material obtained by mixing a powdery magnetic material with the equipment having an adhesive component in any one of the first to fourth inventions, and fixing it to a belt-like insulator. You can handle your body easily.

  In particular, the sixth invention provides a magnetic material which is sintered by providing a magnetic body sintered in a rod shape in any one of the first to fourth inventions, and fixing the magnetic bodies side by side to a strip-like insulator. You can handle your body easily.

  In the seventh invention, in particular, in any one of the first to sixth inventions, an adhesive member is provided on at least a part of the surface of the spacer facing the electric conductor, and the spacer and the electric conductor are fixed, and the spiral processing is performed. The shape of the subsequent heating coil can be maintained, the handling of the heating coil at the time of assembly is improved, and the productivity can be improved.

  In an eighth aspect of the present invention, in particular, the electric conductor is composed of a plurality of conductor wires in any one of the first to seventh aspects of the invention. It becomes easy to process, and it becomes easy to process the electric conductor itself in a spiral shape, thereby improving productivity. Further, since the surface area of the electric conductor is increased, the high frequency resistance of the electric conductor itself can be reduced, and as a result, the heat loss of the heating coil can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows a cross-sectional view of a heating coil for an induction heating apparatus according to a first embodiment of the present invention.

  In FIG. 1, the electric conductor 5 is formed, for example, in a spiral shape with a gap between turns of a copper wire. A strip-like insulator 6 (for example, a thin plate-like mica plate) has a plate-like magnetic body 7 fixed on one side with an adhesive 8 to form a spacer 9.

  In addition, in the spacer 9, the magnetic material 7 is bonded to the insulator 6 in advance only at the inner peripheral portion and the outer peripheral portion of the spiral electric conductor 5. Therefore, the intermediate peripheral portion is only the insulator 6. ing. Reference numerals 10a and 10b denote adhesives which are configured by adhering and fixing spacers 9 in the gaps between the spiral electric conductors 5.

  About the heating coil for induction heating apparatuses comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, a high frequency current is passed through the electric conductor 5 of the heating coil for the induction heating device to induce induction heating. At that time, a magnetic field is generated from the electric conductor 5 and the current is suppressed between the turns of the electric conductor 5. The action (proximity effect) tries to increase the high-frequency resistance of the heating coil, but in the present embodiment, the magnetic flux generated from the electric conductor 5 is concentrated on the magnetic body 7 provided between the turns of the electric conductor 5. Thus, the action (proximity effect) of suppressing the current between the turns of the electric conductor 5 can be reduced, the high frequency resistance of the heating coil can be reduced, and as a result, the heat loss of the heating coil can be reduced.

  In addition, since the spacer 9 is configured by adhering and fixing the magnetic body 7 to the strip-shaped insulator 6 in advance, it can be easily formed into a spiral shape, and the thickness of the insulator 6 can be adjusted even if the magnetic body 7 is thin. By doing so, the dimension between the turns of the electric conductor 5 can be secured.

  Furthermore, by processing the electric conductor 5 and the spacer 9 together, the magnetic body 7 can be easily formed between the turns of the electric conductor 5, and the productivity is extremely excellent.

  Further, in this embodiment, the magnetic body 7 is provided on the inner and outer peripheral portions where the influence of the magnetic field between turns is particularly large. In such processing, the magnetic body 7 is bonded and fixed to the insulator 6 in advance. At this time, it is sufficient to consider the place where the magnetic body 7 is fixed at the time of creating the spacer 9, and there is also an advantage that the fixing position of the magnetic body 7 can be freely changed.

  Further, many of the magnetic bodies 7 have conductivity and require insulation between the turns of the electric conductor 5, but in the present embodiment, the spacer 9 itself is composed of the insulator 6, and the electric conductor Insulation between 5 turns is also secured.

  Of course, when the magnetic body 7 is very excellent in electrical conductivity, it is necessary to consider conducting in the longitudinal direction of the magnetic body 7, but in this case, in the longitudinal direction of the insulator 6. Thus, if places where the magnetic body 7 is not fixed are provided in some places, conduction in the longitudinal direction stops at this place, and can be easily solved.

  As described above, in this embodiment, the spacer 9 having the magnetic body 7 fixed to at least one surface of the strip-shaped insulator 6 is provided, and the electric conductor 5 is formed in a spiral shape with a gap between turns. The magnetic body 7 is provided between the electric conductors 5 by providing the spacers 9 to reduce the high-frequency resistance of the coil when the electric conductors 5 are spiraled, reduce the heat loss, and achieve stable processing. Thus, it is possible to provide a heating coil for an induction heating apparatus with extremely improved productivity.

  In addition, when a magnetic field acts on the magnetic body of the present embodiment, the magnetic body itself self-heats slightly, but by using a soft magnetic body with little loss due to the magnetic field, the magnetic flux generated from the electric conductor 5 is reduced to the magnetic body. The self-heating generated when passing through can be reduced.

(Embodiment 2)
2 is a cross-sectional view of a heating coil for an induction heating device according to a second embodiment of the present invention, and FIG. 3 is a perspective view of a main part of the heating coil for the induction heating device according to a second embodiment of the present invention. It is shown.

2 and 3, the electric conductor 5 is formed in a spiral shape with a gap between turns, for example, a copper wire. The strip-shaped insulators 11a and 11b (for example, a thin plate-like mica plate) are obtained by attaching a powdery magnetic body 12 (for example, ferrite) to equipment (for example, a silicon adhesive) having an adhesive component between the insulators 11a and 11b. The mixed magnetic substance mixture 13 is enclosed.

  Also, the spacers 16 are formed by alternately providing the locations 14 and the locations 15 that the magnetic substance mixture 13 has between the insulators 11a and 11b. Further, the locations where the magnetic substance mixture 13 in the spacer 16 is provided in advance are only the inner and outer peripheral portions of the spiral electric conductor 5, and therefore, the middle peripheral portion is only the insulators 11a and 11b. ing. Reference numerals 17a and 17b denote adhesives which are configured by adhering and fixing the spacers 16 in the gaps between the spiral electric conductors 5.

  About the heating coil for induction heating apparatuses comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, description of operations similar to those of the first embodiment will be omitted. In the present embodiment, the powdered magnetic body 12 is mixed with the equipment having the adhesive component to form the magnetic body mixture 13, and this magnetic body mixture 13 is adhered to the insulators 11a and 11b. The amount of the magnetic body 12 to be attached to the insulators 11a and 11b can be easily changed by adjusting the ratio of the magnetic body mixture 13 or the composition ratio of the magnetic body mixture 13.

  Moreover, since the magnetic body mixture 13 is adhered between the insulators 11a and 11b, the magnetic body mixture 13 can be reliably held. In particular, the magnetic substance mixture 13 in which the powdery magnetic substance 12 is mixed is effective because the powdery magnetic substance 12 can be easily removed.

  Furthermore, since the magnetic body 12 is held between the insulators 11a and 11b, insulation between the turns of the electric conductor 5 can be ensured even if the magnetic body 12 is conductive.

  Further, since the insulators 11a and 11b are made of mica plates having excellent heat resistance, it is necessary to be concerned about the insulation deterioration between turns even if the electrical conductor 5 reaches a high temperature of about 300 ° C. There is no.

  Compared to a heating coil using ordinary enamel-coated wires, the heat resistance can be greatly improved. Furthermore, since ferrite belonging to the soft magnetic material is used for the magnetic material 12, self-heating when the magnetic field generated from the electric conductor 5 passes through the magnetic material can be greatly reduced.

  Further, by providing the spacer 16 with the portion 14 having the magnetic substance mixture 13 and the portion 15 not having the magnetic substance mixture 13, the spacer 16 itself can have flexibility, and the spacer 16 can be easily spiraled and produced. Improves.

  As described above, in the present embodiment, the magnetic material mixture 13 in which the powdery magnetic material 12 is mixed in the equipment having the adhesive component between the strip-shaped insulators 11a and 11b is sealed, and the magnetic material mixture 13 is sealed. Are provided alternately between the places 14 and no places 15 between the insulators 11a and 11b to form a spacer 16, and the electric conductor 5 is formed in a spiral shape with a gap between turns, and the spacer 16 is provided in the gap. By providing, the magnetic body 12 is provided between the electric conductors 5, the high-frequency resistance of the coil when the electric conductor 5 is formed in a spiral shape is reduced, the heat loss is reduced, and the powder-like magnetic body 12 is provided. Thus, it is possible to provide a heating coil for an induction heating apparatus that can perform stable processing, increase flexibility, improve productivity, and have excellent insulation between turns.

In the present embodiment, the portions 14 that the magnetic material mixture 13 has between the insulators 11 a and 11 b and the portions 15 that do not exist are alternately provided to increase the flexibility of the spacers 16. The flexibility of the spacer 16 may be increased by alternately creating a portion having a large thickness and a portion having a small thickness.

(Embodiment 3)
FIG. 4 is a cross-sectional view of a heating coil for an induction heating device according to a third embodiment of the present invention, and FIG. 5 is a perspective view of a main part of the heating coil for the induction heating device according to a third embodiment of the present invention. Is.

  4 and 5, the electric conductor 5 is formed, for example, in a spiral shape with a gap between turns of a copper wire. In the strip-shaped insulators 11a and 11b (for example, thin plate-like mica plates), a magnetic body 18 (for example, ferrite) sintered in a cylindrical shape is fixed with an adhesive 19 between the insulators 11a and 11b.

  Further, since the outer periphery of the magnetic body 18 is covered with the insulators 11a and 11b, there is no magnetic body 18 between the adjacent magnetic bodies 18 in which the insulators 11a and 11b are fixed by the adhesive 19. The spacer 21 is formed while providing the location 20.

  Further, the magnetic material 18 in the spacer 21 is provided in advance only on the inner and outer peripheral portions of the spiral electric conductor 5, and therefore the middle peripheral portion is only the insulators 11a and 11b. Yes. Reference numerals 17a and 17b denote adhesives which are configured by adhering and fixing the spacers 21 in the gaps between the spiral electric conductors 5.

  About the heating coil for induction heating apparatuses comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, description of operations similar to those of the first and second embodiments is omitted. In the present embodiment, even if the sintered magnetic body 18 is used, the flexibility of the spacer 21 can be made by the portion 20 where the magnetic body 18 is not present, and the spacer 21 is inserted into the space between the spiral electric conductors 5. Can do.

  In addition, the sintered ferrite magnetic body 18 has excellent properties of high magnetic permeability and low self-heating, but it is not flexible and difficult to form in a spiral shape. However, it can be solved by configuring as in the present embodiment.

  As described above, in the present embodiment, the magnetic body 18 sintered in a cylindrical shape is fixed between the strip-shaped insulators 11 a and 11 b with the adhesive 19, and the insulator 11 a is interposed between the adjacent magnetic bodies 18. , 11b are fixed with an adhesive 19 and a spacer 21 is formed while providing a portion 20 without a magnetic body 18, and the electric conductor 5 is spiraled with a gap between turns, and the spacer 21 is placed in the gap. By having it, it is set as the structure which provides the magnetic body 18 between the electrical conductors 5, and reduces the high frequency resistance of the coil at the time of making the electrical conductor 5 into a spiral shape, lowers heat loss, and is sintered with high permeability. By using the magnetic body 18, it is possible to provide a heating coil for an induction heating device that can perform stable processing, increase flexibility, improve productivity, and have excellent insulation between turns.

  In the first to third embodiments, the magnetic body is provided only on the inner and outer peripheral portions of the spiral electric conductor, and no magnetic body is provided on the middle peripheral portion. For example, you may provide a magnetic body only in an inner peripheral part, or all.

  In the first to third embodiments, a copper plate-like wire is used as the electric conductor. However, the electric conductor is not limited to an electric conductor. You may use for a conductor.

(Embodiment 4)
FIG. 6 is a sectional view of a heating coil for an induction heating device according to a fourth embodiment of the present invention, and FIG. 7 is a perspective view of a main part of the heating coil for the induction heating device according to a fourth embodiment of the present invention. Is.

  6 and 7, the electric conductor 22 having a thin insulating film on the surface of each of three thin copper plates (for example, about 0.2 mm thick) is formed in a spiral shape with a gap between turns. The strip-shaped insulators 11a and 11b (for example, a thin plate-like mica plate) are obtained by attaching a powdery magnetic body 12 (for example, ferrite) to equipment (for example, a silicon adhesive) having an adhesive component between the insulators 11a and 11b. The mixed magnetic substance mixture 13 is thinly sealed (for example, about 0.2 mm) to form a spacer 23.

  The adhesives 17 a and 17 b are configured to include the magnetic body 12 in all the turns of the electric conductor 22 by inserting and fixing the spacer 23 in the gap between the spiral electric conductors 22.

  About the heating coil for induction heating apparatuses comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, description of operations similar to those of the first to third embodiments is omitted. In the present embodiment, the spacer 23 can be made flexible by reducing the thickness of the magnetic material mixture 13 and providing it between the insulators 11 a and 11 b, and the spacer 23 is placed in the gap between the spiral electric conductors 22. Can be put.

  In addition, since the electric conductor 22 is composed of three thin copper plates, when a high frequency current is passed through the electric conductor 22, it tends to flow on the conductor surface. The surface area of the conductor 22 is increased to facilitate the flow of high-frequency current.

  That is, the high frequency resistance of the electric conductor 22 can be lowered, and the heat loss from the electric conductor 22 when a high frequency current flows through the electric conductor 22 can be reduced. Furthermore, by configuring the electric conductor 22 with three thin copper plates, the electric conductor 22 itself can be made flexible and can be easily processed into a spiral shape.

  As described above, in this embodiment, the magnetic material mixture 13 in which the powdered magnetic material 12 is mixed with the equipment having the adhesive component between the strip-shaped insulators 11a and 11b is enclosed with a small thickness. 23, the electric conductor 22 is composed of three thin copper plates, the electric conductor 22 is formed in a spiral shape with a gap between turns, and a spacer 23 is provided in the gap. With the configuration in which the magnetic body 12 is provided, it is possible to reduce the high frequency resistance of the coil when the electric conductor 22 is spirally formed.

  Further, the high-frequency resistance of the electric conductor 22 itself can be lowered by configuring the electric conductor 22 with three thin copper plates, and a heating coil for an induction heating apparatus with reduced heat loss can be provided. In addition, it is possible to provide a heating coil for an induction heating device that improves flexibility with respect to each of the spacer 23 and the electric conductor 22, improves productivity, and is excellent in insulation between turns.

In the present embodiment, the electric conductor 22 is composed of three thin copper plates that are thin in the circumferential direction. However, the electrical conductor 22 may be composed of any number of thin plates, and a plurality of thin copper plates may be formed in the vertical direction. The sheets may be stacked, and a plurality of clothes thin wires (about φ0.3 mm) may be provided. In short, by configuring the electric conductor with a plurality of wires, the high-frequency resistance of the electric conductor can be lowered by increasing the surface area relative to the total cross-sectional area of the electric conductor, and as a result, the heat loss of the heating coil is reduced. be able to.

  In the embodiment, the thickness of the copper plate of the electric conductor 22 is about 0.2 mm, and the thickness of the magnetic material mixture 13 is about 0.2 mm. Thickness can be used.

  In Embodiments 1 to 4, the spiral electric conductor and the spacer are fixed with an adhesive. However, a fusion varnish, a fusible resin, or the like is previously attached to the electric conductor or the spacer. If a spacer is attached between the spiral electric conductors, and then the electric conductor is energized to melt the fusion varnish or fusible resin, and the electric conductor and the spacer are fixed, the productivity is further improved. be able to.

  In Embodiments 1 to 4, the electric conductor and the magnetic body (or magnetic substance mixture) have substantially the same width, but the width of the magnetic body is increased and the electric conductor is provided in the center. By the action of the magnetic field from the electric conductor, the action of suppressing the current between the turns of the electric conductor 5 (proximity effect) can be further suppressed by the magnetic body wider than the electric conductor, and the high frequency resistance of the heating coil is further reduced. As a result, the heat loss of the heating coil can be greatly reduced.

  In Embodiments 1 to 4, the spacer is provided on the outermost peripheral side of the coil. However, the electrical conductor may be provided on the outermost peripheral side of the coil. A spacer may be provided on the surface.

  In Embodiments 1 to 4, a thin plate-like mica plate is used for the spacer in the form of a spacer. However, a heat-resistant resin such as a fluororesin may be used. In short, the temperature of the heating coil is increased. It is sufficient that the insulator has a heat resistance that does not hinder the above.

(Embodiment 5)
FIG. 8: shows sectional drawing of the form which used the heating coil for induction heating apparatuses in the 5th Embodiment of this invention for the induction heating cooking appliance.

  In FIG. 8, the heating coil 24 uses the heating coil for induction heating apparatus of the fourth embodiment. Therefore, the configuration of the heating coil 24 is the same as that of the fourth embodiment (FIGS. 6 and 7), and only the component number and name are described here.

  The heating coil 24 is a magnetic body obtained by mixing the strip-shaped insulators 11a and 11b, the powder-shaped magnetic body 12, and the equipment (for example, silicon adhesive) having an adhesive component with the powder-shaped magnetic body 12 (for example, ferrite). The mixture 13, the adhesives 17 a and 17 b, and the three thin copper plates (for example, about 0.2 mm thick) are each configured by an electric conductor 22 and a spacer 23 provided with a thin insulating film on the surface. It is the same configuration.

  The upper and lower surfaces of the heating coil 24 are provided with an upper insulating plate 25 and a lower insulating plate 26 made of, for example, mica plates. It is provided radially from.

The heating coil base 28 that holds the rod-shaped magnetic body 27 is made of, for example, a heat-resistant resin such as PBT. A support plate 29 made of an aluminum plate supports the components around the heating coil 24. For example, the top plate 30 made of crystallized glass or the like is fixed to the upper surface of the outer shell 31 of the product so that a metal heated object 32 such as a pot can be placed on the top plate 30.

  A heating coil 24 is provided on the lower surface of the top plate 30, and an upper insulator 25 is provided between the top plate 30 and the heating coil 24. The drive circuit 33 is fixed on a resin circuit base 34 below the support plate 29 and supplies a high-frequency current to the heating coil 24. The cooling fan 35 sucks air from the outside of the outer shell 31 as indicated by an arrow A, cools heat generating components such as the drive circuit 33 and the heating coil 24, and exhausts the outside of the outer shell 31 as indicated by an arrow B.

  About the induction heating cooking appliance comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, a heated object 32 such as a pan is placed on the top plate 30, and a high frequency magnetic field is generated from the heating coil 24 by flowing a high frequency current from the driving circuit 33 to the heated coil 24. The high frequency magnetic field acts and induction heating occurs.

  At this time, the electric conductor 22 of the heating coil 24 has a configuration in which the magnetic body 12 is provided between the electric conductors 22 to reduce the high-frequency resistance when the electric conductor 22 is formed in a spiral shape. The high frequency resistance of the electric conductor 22 itself can also be lowered by using a thin copper plate, and the self-heating of the heating coil 24 is very low.

  Thereby, the cooling of the heating coil 24 can be reduced, and as a result, the cooling capacity of the cooling fan 35 can be reduced, and the cooling fan 35 can be reduced in size and noise.

  Further, the magnetic flux in the magnetic field generated from the heating coil 24 flows not only to the rod-shaped magnetic body 27 but also to the magnetic body 12 in the heating coil 24, and more magnetic flux concentrates on the bottom surface of the object to be heated 32. As a result, the magnetic field generated from the electric conductor 22 is easily transmitted to the object to be heated 32, and the heating efficiency of the object to be heated 32 is improved.

  Furthermore, since a mica plate is used for the strip-shaped insulators 11a and 11b between the turns of the electric conductor 22 of the heating coil 24, the insulation performance is reduced even when the heating coil 24 reaches a high temperature of about 300 ° C. There is no problem.

  Of course, the heat resistance of the insulating film applied to the surface of the electric conductor 22 needs to be taken into consideration, but since the adjacent electric conductors 22 in the turn have the same potential, there is no problem even if the insulating property is somewhat lowered. Therefore, normally, a space is provided between the top plate 30 and the heating coil 24 and the heating coil is cooled through cooling air. However, since the heating coil 24 of the present embodiment has high heat resistance, Since there is no problem even if the temperature of 32 becomes high, it can be provided in the vicinity of the top plate 30.

  By this action, the distance between the heating coil 24 and the object to be heated 31 can be shortened, and the magnetic field generated from the heating coil 24 can be easily transmitted to the object to be heated 32, and as a result, the heating efficiency of the object to be heated 32 is further improved. be able to.

  As described above, by using the heating coil for the induction heating device in the fourth embodiment for the induction heating cooker, the heat loss of the heating coil 24 can be reduced, and the heating coil 24 is structurally excellent in heat resistance. Therefore, the heating coil can be configured close to the lower surface of the top plate 30, the heating efficiency of the object to be heated 32 can be improved, the cooling of the heating coil 24 can be reduced, and the cooling fan 35 can be reduced in size. And noise reduction can be achieved.

  In the present embodiment, the heating coil according to the fourth embodiment is used as the heating coil 24. However, the heating coil according to the first to third embodiments may be used. What is necessary is just to use the heating coil which provided the spacer which fixed the magnetic body to at least one part of this insulator.

  As described above, the heating coil for an induction heating device according to the present invention has a high frequency resistance, a small heat loss, and a stable processing of a heating coil having excellent insulation between turns, thereby improving productivity. Therefore, the present invention can also be applied to industrial fields using induction heating.

5, 22 Electrical conductor 6, 11a, 11b Insulator 7, 12, 18 Magnetic body 9, 16, 21, 23 Spacer

Claims (8)

A heating coil for an induction heating device in which a spacer having a magnetic material fixed is provided on at least one surface of a strip-shaped insulator, and an electric conductor is formed in a spiral shape with a gap between the turns of the electric conductor. The heating coil for an induction heating device according to claim 1, further comprising a spacer having a magnetic material fixed inside two strip-shaped insulators. The heating coil for an induction heating device according to claim 1 or 2, wherein at least a part of the spacer is formed with a portion where no magnetic material is provided. The heating coil for induction heating devices according to any one of claims 1 to 3, wherein a portion with a large thickness and a portion with a small thickness of the magnetic material, or a portion with and without a magnetic material are provided alternately. The heating coil for an induction heating device according to any one of claims 1 to 4, wherein a powdery magnetic material is mixed with an equipment having an adhesive component and fixed to a belt-like insulator. The heating coil for induction heating devices according to any one of claims 1 to 4, wherein a magnetic body sintered in a rod shape is provided, and a plurality of the magnetic bodies are arranged and fixed on a strip-shaped insulator. The heating coil for an induction heating device according to any one of claims 1 to 6, wherein an adhesive member is provided on at least a part of a surface of the spacer facing the electric conductor, and the spacer and the electric conductor are fixed. The induction coil heating coil according to any one of claims 1 to 7, wherein the electric conductor is composed of a plurality of conductor wires.