JP2019117758A - Induction heating cooker - Google Patents

Abstract

To improve convenience.SOLUTION: An induction heating cooker (1) comprises: a heating plate (10) that has a plurality of heat generation parts (12a, 12b) subjected to induction heating and a heat transfer part (11) for conducting heat generated at the plurality of heat generation parts; a top plate (22) that mounts the heating plate; a plurality of heating coils (23a, 23b) arranged below the top plate and arranged in a region where the plurality of heat generation parts are projected when seen from a thickness direction (a Z direction) of the heating plate, and that performs induction heating of the plurality of heat generation parts, respectively; a plurality of inverters (42a, 42b) that supply a high-frequency current to each of the plurality of heating coils; and a controller (41) that controls an output of each of the plurality of inverters.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an induction heating cooker.

  As an induction heating cooker, the induction heating cooker of patent document 1 is known, for example. In the induction heating cooker described in Patent Document 1, a plurality of heating coils are provided below one heating plate, and the power of the plurality of heating coils is individually varied.

Unexamined-Japanese-Patent No. 5-242959 gazette

  However, Patent Document 1 still has room for improvement in terms of improving convenience.

  Therefore, an object of the present invention is to solve the above-mentioned problems, and to provide an induction heating cooker that can improve convenience.

In order to achieve the above object, an induction heating cooker according to an aspect of the present invention,
A heating plate having a plurality of heat generating parts to be inductively heated, and a heat transfer part that conducts heat generated by the plurality of heat generating parts;
A top plate on which the heating plate is placed;
And a plurality of heating coils disposed below the top plate and disposed in a region where the plurality of heating portions are projected when viewed from the thickness direction of the heating plate, and inductively heating the plurality of heating portions, ,
A plurality of inverters for supplying a high frequency current to each of the plurality of heating coils;
A control unit configured to control an output of each of the plurality of inverters;
Equipped with

  According to the induction heating cooker of the present invention, the convenience can be improved.

FIG. 1 is a perspective view of an example of an induction heating cooker according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the induction heating cooker of FIG. FIG. 3 is a bottom view of an example heating plate. FIG. 4 is a perspective view of an example of the main body. FIG. 5A is a cross-sectional view of the induction heating cooker of FIG. 1 taken along the line B-B. FIG. 5B is a partially enlarged cross-sectional view of the Z1 portion of the induction heating cooker of FIG. 5A. FIG. 6 is a perspective view when an example of the induction heating cooker according to the embodiment of the present invention is viewed from below. FIG. 7 is an exemplary control block diagram. FIG. 8 is a circuit diagram of a part of an exemplary control circuit of the induction heating cooker 1 according to the embodiment of the present invention. FIG. 9 is a schematic diagram showing an internal configuration of an exemplary body. FIG. 10 is a schematic partial configuration diagram showing an example of the configuration inside the main body around the cooling fan disposed on one end side of the main body. FIG. 11 is another schematic partial configuration diagram showing an example of the configuration inside the main body around the cooling fan arranged on one end side of the main body. FIG. 12A is a diagram showing an example of heating control of the induction heating cooker 1 according to the embodiment of the present invention. FIG. 12B is a diagram showing another example of the heating control of the induction heating cooker 1 according to the embodiment of the present invention. FIG. 13 is a diagram showing an example of detailed heating control of the induction heating cooker 1 according to the embodiment of the present invention. FIG. 14 is a graph showing an example of an experimental result when a heating experiment is performed in the induction heating cooker according to the embodiment of the present invention. FIG. 15: is a schematic block diagram of an example of the state which attached the flame | frame to the induction heating cooker which concerns on embodiment of this invention.

(Findings that formed the basis of this disclosure)
As an induction heating cooker, what carries out induction heating of the heating plate which heats cooking matter by a plurality of heating coils is known.

  In such an induction heating cooker, induction heating of the whole bottom part of a heating plate is carried out by a plurality of heating coils. Therefore, even when the heating plate is inductively heated by any of the plurality of heating coils, the entire bottom of the heating plate is heated.

  For example, consider a case where the heating plate is divided into a plurality of heating areas for heating a plurality of food items to be heated. In this case, even if the plurality of heating coils heat the plurality of heating regions at different temperatures, it is difficult to realize the heating temperature set by the user or the like in each of the plurality of heating regions.

  Therefore, in such an induction heating cooker, in each of the several heating area | regions on a heating plate, a cooking material can not be heated at desired heating temperature, but it has become inconvenient for a user.

  Therefore, the inventors of the present invention conducted intensive studies to achieve the set heating temperature in each of the plurality of heating areas on the heating plate. The inventors of the present invention have a configuration of an induction heating cooker in which a heating plate having a plurality of induction heating parts and a heat transfer part that conducts heat generated in the plurality of heating parts is inductively heated by a plurality of heating coils. The following invention was reached.

The induction heating cooker of the first aspect of the present invention is
A heating plate having a plurality of heat generating parts to be inductively heated, and a heat transfer part that conducts heat generated by the plurality of heat generating parts;
A top plate on which the heating plate is placed;
And a plurality of heating coils disposed below the top plate and disposed in a region where the plurality of heating portions are projected when viewed from the thickness direction of the heating plate, and inductively heating the plurality of heating portions, ,
A plurality of inverters for supplying a high frequency current to each of the plurality of heating coils;
A control unit configured to control an output of each of the plurality of inverters;
Equipped with

  In the induction heating cooker according to the second aspect of the present invention, the plurality of heat generating portions may be formed of a metal material having a higher electrical resistance value than the metal material forming the heat transfer portion.

In the induction heating cooker according to the third aspect of the present invention, the heating plate has a symmetrical shape with respect to a center line of the heating plate extending in the width direction,
The plurality of heat generating portions may be provided symmetrically with respect to the center line of the heating plate.

  In the induction heating cooker according to the fourth aspect of the present invention, the heating plate has a positioning portion which protrudes from the lower surface of the heating plate toward the top plate and is located at the outer edge of the top plate. It is also good.

  In the induction heating cooker according to the fifth aspect of the present invention, the heating plate protrudes from the lower surface of the heating plate toward the top plate along the lengthwise direction of the heating plate and the outer edge of the top plate It may have a rib located at

  In the induction heating cooker according to the sixth aspect of the present invention, the lower end of the rib may be located below the upper surface of the top plate and above the lower surface of the top plate.

  In the induction heating cooker according to the seventh aspect of the present invention, the heating plate may have a leg portion extending from the lower surface of the heating plate to the top plate only on the outside of the plurality of heat generating portions.

  In the induction heating cooker according to the eighth aspect of the present invention, the heating plate is capable of cooking across a plurality of heating areas to be heated by the plurality of heating portions, and partitions the plurality of heating areas. You may have a partition part.

  In the induction heating cooker according to the ninth aspect of the present invention, the partition portion is provided on the upper surface of the heating plate along a center line extending in the width direction of the heating plate when viewed from the thickness direction of the heating plate. It may be a recessed portion.

The induction heating cooker according to the tenth aspect of the present invention further comprises a frame disposed on the outer edge of the heating plate,
The frame may have a frame leg extending downward from the top plate and in contact with the outer edge of the main body on which the top plate is placed.

  In the induction heating cooker according to the eleventh aspect of the present invention, the rib may be located inside the outer surface of the heating plate.

  Hereinafter, embodiments of the present disclosure will be described with reference to the attached drawings. Moreover, in each figure, in order to make description easy, each element is shown exaggeratingly.

Embodiment
[overall structure]
An example of the induction heating cooker which concerns on embodiment of this invention is demonstrated. FIG. 1 is a perspective view of an example of an induction heating cooker 1 according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the induction heating cooker 1 of FIG. FIG. 3 is a perspective view of an example of the main body 20. FIG. In the drawings, the X, Y and Z directions respectively mean the width direction, the length direction and the thickness direction of the induction heating cooker 1.

  As shown in FIGS. 1 to 3, the induction heating cooker 1 includes a heating plate 10 and a main body 20 on which the heating plate 10 is placed.

[Heating plate]
The heating plate 10 is a plate on which the food is placed and heated on the upper surface. As shown in FIG. 1, the heating plate 10 is a thin plate-like flat plate. The heating plate 10 is formed in, for example, a rectangular shape as viewed in the thickness direction, that is, in the Z direction. The heating plate 10 has a left-right symmetrical shape with respect to a center line CL1 extending in the width direction, that is, the X direction. The center line CL1 extending in the width direction of the heating plate 10 means a line at equal distances from both ends in the longitudinal direction of the heating plate 10, that is, the Y direction, as viewed from the thickness direction of the heating plate 10.

  In the embodiment, the heating plate 10 is formed in a concave shape. Specifically, the heating plate 10 is formed by bending the outer edge of the flat plate member to the side opposite to the main body 20 side.

  As shown in FIG. 2, the heating plate 10 has a heat transfer portion 11, a plurality of heat generating portions 12 a and 12 b, a positioning portion 13, and a rib 14.

  Further, on the upper surface of the heating plate 10, a partition portion 15 for partitioning the plurality of heating areas A1 and A2 is formed. The plurality of heating areas A1 and A2 are areas heated by the plurality of heat generating portions 12a and 12b, respectively.

  FIG. 4 is a bottom view of an example of the heating plate 10. As shown in FIG. 4, a plurality of legs 16 is provided on the lower surface of the heating plate 10.

<Heat transfer section>
The heat transfer portion 11 constitutes the outer shape of the heating plate 10, and is connected to the plurality of heat generating portions 12a and 12b. The heat transfer portion 11 is formed of a metal material that conducts the heat generated by the plurality of heat generating portions 12a and 12b, and is formed of a nonmagnetic material. In the present specification, “nonmagnetic material” means a material that is not a ferromagnetic material and has a magnetic permeability lower than that of the plurality of heat generating portions 12 a and 12 b.

Moreover, the heat transfer part 11 is formed with a metal material whose electric resistance, ie, a specific resistance, is smaller than the metal material which forms several heat-emitting part 12a, 12b. For example, the metal resistance of the metal material forming the heat transfer portion 11 is preferably 1.5 × 10 ⁻⁸ mΩ or more and less than 3.0 × 10 ⁻⁸ mΩ in an environment of 20 ° C. The metal resistance of the embodiment is 2.7 × 10 ⁻⁸ mΩ.

  Moreover, the heat transfer part 11 is formed with the metal material whose heat conductivity is larger than the metal material which forms several heat-emitting part 12a, 12b.

  For example, as a material of the heat transfer part 11, aluminum, nonmagnetic stainless steel, etc. are mentioned. Examples of nonmagnetic stainless steel include austenitic stainless steel.

  In the embodiment, the heat transfer portion 11 is formed of aluminum. Aluminum is hard to be inductively heated because it is hard to be affected by the magnetic field. For this reason, by connecting the first heat generating portion 12 a and the second heat generating portion 12 b via the heat transfer portion 11, it is easy to separate the heating region to be inductively heated. On the other hand, aluminum is a metal that easily conducts heat, so it is easy to conduct the heat generated in each of the plurality of heat generating portions 12 a and 12 b in the heating region. The thermal conductivity of aluminum is 240 W / m · K in an environment of 100 ° C. Furthermore, since aluminum is a lighter metal than iron or the like, the heating plate 10 can be made lighter. Therefore, the heating plate 10 can be easily lifted.

<Heating portion>
As shown in FIGS. 2 and 4, the plurality of heat generating portions 12 a and 12 b are formed on the lower surface of the heating plate 10, that is, the lower surface of the heat transfer portion 11. The plurality of heat generating portions 12 a and 12 b are aligned in the longitudinal direction of the heating plate 10, that is, in the Y direction. Further, the plurality of heat generating portions 12 a and 12 b are formed apart from each other in the length direction of the heating plate 10, and are connected via the heat transfer portion 11. Specifically, the plurality of heat generating portions 12a and 12b are connected across the heat transfer portion 11 so as not to be directly connected to each other.

  In the embodiment, the plurality of heat generating portions 12 a and 12 b are provided symmetrically with respect to the center line CL 1 of the heating plate 10. The plurality of heat generating portions 12a and 12b are formed in the same size and the same shape. Specifically, the plurality of heat generating portions 12a and 12b are formed, for example, in an annular shape. Further, when viewed from the lower surface side of the heating plate 10, the plurality of heat generating portions 12a and 12b are formed with a plurality of positioning irregularities.

  When viewed in the thickness direction of the heating plate 10, the plurality of heat generating portions 12a and 12b are formed to have a larger area than the plurality of heating coils 23a and 23b housed inside the main body 20.

  The plurality of heat generating portions 12a and 12b are formed of a metal material that can generate heat by electromagnetic induction. The plurality of heat generating portions 12a and 12b are formed of a magnetic material. In other words, the metal material forming the plurality of heat generating portions 12 a and 12 b has a permeability higher than that of the metal material forming the heat transfer portion 11.

The plurality of heat generating portions 12 a and 12 b are formed of a metal material having a higher electrical resistance value than the metal material forming the heat transfer portion 11. For example, the electrical resistance of the metal material forming the plurality of heat generating portions 12a and 12b is preferably 10 × 10 ⁻⁸ mΩ or more and 70 × 10 ⁻⁸ mΩ or less in an environment of 20 ° C. More preferably, the electrical resistance of the metal material forming the plurality of heat generating portions 12a and 12b is 60 × 10 ⁻⁸ mΩ or more and 70 × 10 ⁻⁸ mΩ or less.

  For example, as a material for forming the plurality of heat generating parts 12a and 12b, iron, stainless steel, etc. may be mentioned. Examples of stainless steel include SUS304 and SUS430. The thermal conductivity of SUS304 and SUS430 is 16 W / m · K and 26 W / m · K, respectively, in an environment of 100 ° C.

<Positioning unit>
As shown in FIG. 2, the positioning portion 13 protrudes from the lower surface of the heating plate 10 toward the top plate 22 mounted on the main body 20, and is positioned at the outer edge of the top plate 22. The positioning unit 13 positions the heating plate 10 when the heating plate 10 is placed on the main body 20.

  The heating plate 10 has a plurality of positioning portions 13. In the embodiment, the heating plate 10 has four positioning portions 13. The plurality of positioning portions 13 are provided at the four corners of the heating plate 10. The plurality of positioning portions 13 respectively project from the corner of the heating plate 10 toward the main body 20 side. When the heating plate 10 is placed on the main body 20, the plurality of positioning portions 13 are arranged to surround the corner of the top plate 22, respectively. The plurality of positioning portions 13 are each formed of a bent plate-like member so as to correspond to the shape of the corner portion of the top plate 22.

  Thus, the heating plate 10 can be positioned on the top plate 22 of the main body 20 by forming the positioning portion 13 on the outer edge of the heating plate 10.

<Rib>
As shown in FIGS. 2 and 4, the ribs 14 project from the lower surface of the heating plate 10 toward the top plate 22 placed on the main body 20 along the length direction of the heating plate 10, that is, the Y direction. , Located on the outer edge of the top plate.

  The heating plate 10 has a plurality of ribs 14. In the embodiment, the heating plate 10 has two ribs 14. The plurality of ribs 14 are respectively formed along the outer edge of the heating plate 10 in the longitudinal direction. Further, the plurality of ribs 14 extending along the outer edge in the longitudinal direction of the heating plate 10 are each integrally formed with the positioning portion 13 formed at the corner of the heating plate 10. The plurality of ribs 14 are each formed in a plate shape.

  FIG. 5A is a cross-sectional view of the induction heating cooker 1 of FIG. 1 taken along the line B-B. FIG. 5B is a partially enlarged cross-sectional view of the Z1 portion of the induction heating cooker 1 of FIG. 5A. As shown in FIGS. 5A and 5B, a plurality of ribs 14 are formed along the outer edge of the heating plate 10 in the longitudinal direction, ie, the Y direction. The plurality of ribs 14 are formed to project from the lower surface of the heating plate 10 toward the top plate 22 and are disposed along the outer edge 22 a in the longitudinal direction of the top plate 22.

  The ribs 14 are located inside the outer surface 10 a of the heating plate 10. The outer side surface 10a is a surface visually recognized from the outside. By arranging the ribs 14 inside the outer side surface 10 a, the influence on the appearance can be reduced.

  As shown in FIG. 5B, the lower end 14 a of the rib 14 is located below the upper surface 22 b of the top plate 22 placed on the main body 20 and above the lower surface 22 c of the top plate 22. Therefore, a gap S1 is formed between the lower end 14a of the rib 14 and the main body 20.

  In the embodiment, the rib 14 has a thickness equal to the thickness of the heat transfer portion 11 in which the heating area of the heating plate 10 is formed. For example, the thickness of the rib 14 may be 0.5 times or more and 1.5 times or less the thickness of the heat transfer portion 11.

  Thus, heat is accumulated at the longitudinal outer edge of the heating plate 10 by forming the ribs 14 projecting toward the top plate 22 along the longitudinal outer edge of the heating plate 10, and the heating plate 10 heat retention can be enhanced. In addition, the ribs 14 can prevent air from flowing into the lower part of the heating plate 10 without deteriorating the design, and the heat retention can be prevented from being lowered. Furthermore, the ribs 14 can increase the strength of the heating plate 10 and suppress the thermal deformation of the heating plate 10.

  Further, by providing the gap S <b> 1 between the rib 14 and the main body 20, direct conduction of heat of the heating plate 10 from the outer edge of the heating plate 10 to the main body 20 can be suppressed.

<Partition part>
The partition unit 15 partitions the plurality of heating areas A1 and A2 formed on the upper surface of the heating plate 10. In the embodiment, the partition portion 15 is provided on the upper surface of the heating plate 10 along the center line CL1 extending in the width direction of the heating plate 10 when viewed from the thickness direction of the heating plate 10.

  Thus, the partition unit 15 partitions the first heating area A1 heated by the first heat generating section 12a and the second heating area A2 heated by the second heat generating section 12b.

  The partition 15 is, for example, a recess extending along a center line CL1 extending in the width direction of the heating plate 10. By forming the partition portion 15 as a recess, the food can be easily heated across the first heating area A1 and the second heating area A2.

  In addition, by forming the partition portion 15 as a recess, the thickness of the heat transfer portion 11 at the boundary between the first heating area A1 and the second heating area A2 can be made thinner than the thickness of the other flat parts. it can. Thereby, the area which conducts heat in partition part 15 can be made small, and it can control that heat is mutually conducted between 1st heating field A1 and 2nd heating field A2.

<Legs>
The legs 16 extend from the lower surface of the heating plate 10 to the top plate 22 to support the heating plate 10 on the top plate 22. As shown in FIG. 4, the leg portion 16 is provided only on the outside of the plurality of heat generating portions 12 a and 12 b. Specifically, the legs 16 are provided only on the outside of the plurality of heat generating portions 12a and 12b in the length direction of the heating plate 10, that is, in the Y direction. The leg portion 16 is formed of, for example, a cylindrical member extending from the lower surface of the heating plate 10 to the top plate 22.

  In the embodiment, the heating plate 10 has a plurality of legs 16. The plurality of legs 16 are aligned at equal intervals in the width direction of the heating plate 10, that is, in the X direction only on the outside of the plurality of heat generating portions 12a and 12b.

  Thus, by providing the legs 16 on the lower surface of the heating plate 10, the distance between the heating coils 23a and 23b and the heating portions 12a and 12b can be kept constant. Further, by providing the leg portions 16 only on the outside of the plurality of heat generating portions 12a and 12b, the heating plate 10 can be stably supported even when the heating plate 10 is warped by heat.

[Body]
The main body 20 mounts the heating plate 10 on the upper surface, and heats the heating plate 10. As shown in FIG. 3, in the main body 20, the top plate 22 is mounted on the upper surface of the housing 21 that constitutes the outer shape of the main body 20. Further, the main body 20 is provided with an operation display unit 30 on the front of the housing 21.

  As shown in FIG. 2, the main body 20 accommodates a plurality of heating coils 23 a and 23 b, a plurality of temperature detection units 24 a and 24 b, a control board 40, and a cooling fan 51 in a housing 21. ing.

  FIG. 6 is a perspective view of the exemplary induction heating cooker 1 according to the embodiment of the present invention as viewed from below. As shown in FIG. 6, in the main body 20, a lower surface opening 25a is formed in the lower surface on one end side in the length direction of the main body 20 to which the cooling fan 51 is attached, that is, in the Y direction. A side opening 25 b is formed on the side surface at one end side in the length direction of the main body 20. The lower surface opening 25 a and the side opening 25 b are openings for sucking air from the outside of the main body 20 to the inside.

  On the other hand, a lower surface exhaust port 26 a is formed on the lower surface of the other end side in the length direction of the main body 20. Further, as shown in FIG. 2, a side surface exhaust port 26 b is formed on the side surface on the other end side in the length direction of the main body 20. The lower surface exhaust port 26 a and the side surface exhaust port 26 b are exhaust ports for exhausting air from the inside to the outside of the main body 20.

  Further, as shown in FIG. 6, on the side surface on one end side in the length direction of the main body 20, a connection terminal 27 for connecting a power cord for supplying power to the control board 40 is provided.

<Case>
The housing 21 has a first housing 21 a and a second housing 21 b. The first housing 21 a constitutes an outer shape of the upper side of the main body 20. The second housing 21 b constitutes the outer shape of the lower side of the main body 20.

<Top plate>
The top plate 22 is an electrically insulating flat plate on which the heating plate 10 is mounted. The top plate 22 is formed of, for example, an electrical insulator such as glass or ceramic. The top plate 22 is placed on the upper surface of the main body 20, that is, the upper surface of the first housing 21a.

<Operation display section>
The operation display unit 30 has an operation unit 31 for operating functions and settings of the induction heating cooker 1 and a display unit 32 for displaying functions and settings of the induction heating cooker 1. The operation unit 31 determines, for example, the switching on / off of the power supply of the induction heating cooker 1 by the user operating a switch, the heating temperature, the timer, and / or the course selection. The display unit 32 displays, for example, power on / off, a set heating temperature, a set timer, a selected course, and / or a warning when an abnormality is detected. The operation unit 31 and the display unit 32 are controlled by a control unit mounted on the control board 40.

<Heating coil>
The plurality of heating coils 23a and 23b are respectively disposed below the top plate 22 and in a region in which the plurality of heat generating portions 12a and 12b are projected when viewed from the thickness direction of the heating plate 10, that is, the Z direction. ing. In the embodiment, the plurality of heating coils 23a and 23b are disposed at positions facing the plurality of heat generating portions 12a and 12b, respectively. That is, the plurality of heating coils 23a and 23b are in a one-to-one arrangement relationship with the plurality of heat generating portions 12a and 12b, respectively.

  In this specification, the heating coil disposed in the area where the first heat generating portion 12a is projected is the first heating coil 23a, and the heating coil disposed in the area where the second heat generating portion 12b is projected is the second heating coil Description will be made as 23b.

  The first heating coil 23 a and the second heating coil 23 b are each supplied with high frequency current from a plurality of inverters mounted on the control substrate 40. Thereby, while the 1st heating coil 23a carries out induction heating of the 1st exothermic part 12a, the 2nd heating coil 23b carries out induction heating of the 2nd exothermic part 12b.

  In the embodiment, the first heating coil 23 a is attached to the flat mounting plate 52 and disposed adjacent to the cooling fan 51.

<Temperature detection unit>
The plurality of temperature detectors 24a and 24b respectively detect the temperatures of the heating regions A1 and A2. That is, the plurality of temperature detection units 24a and 24b respectively detect the temperatures of the plurality of heat generation units 12a and 12b. The plurality of temperature detection units 24 a and 24 b are disposed on the lower surface of the top plate 22 at positions where the plurality of heating coils 23 a and 23 b are disposed. The plurality of temperature detection units 24a and 24b are disposed in a one-to-one relationship with the plurality of heating coils 23a and 23b, respectively.

  The plurality of temperature detection units 24a and 24b are configured by, for example, a thermistor or an infrared temperature sensor.

  In this specification, the temperature detection unit that detects the temperature of the first heating area A1 will be described as a first temperature detection unit 24a, and the temperature detection unit that detects the temperature of the second heating area A2 will be described as a second temperature detection unit 24b. .

  In the embodiment, the first temperature detection unit 24a is disposed at the center of the first heating coil 23a, and the second temperature detection unit 24b is disposed at the center of the second heating coil 23b. Thereby, the temperatures of the first heat generating portion 12a and the second heat generating portion 12b can be measured with higher accuracy.

  Information on the temperatures detected by the plurality of temperature detection units 24 a and 24 b is transmitted to a control unit mounted on the control board 40.

<Control board>
The control board 40 is a board on which a circuit for controlling the induction heating cooker 1 is mounted. FIG. 7 is an exemplary control block diagram of the induction heating cooker 1. As shown in FIG. 7, the control board 40 includes a control unit 41, a plurality of inverters 42a and 42b, and a plurality of temperature calculation units 43a and 43b. Further, the control unit 41 is connected to the operation unit 31, the display unit 32, and the notification unit 33.

  In the present specification, an inverter supplying high frequency current to the first heating coil 23a will be described as a first inverter 42a, and an inverter supplying high frequency current to the second heating coil 23b will be described as a second inverter 42b. Further, a temperature calculation unit that calculates the temperature of the first heat generating unit 12a based on the temperature information detected by the first temperature detection unit 24a is the first temperature calculation unit 43a, and the temperature detected by the second temperature detection unit 24b A temperature calculation unit that calculates the temperature of the second heat generation unit 12b based on the information will be described as a second temperature calculation unit 43b.

  The elements constituting the control board 40 are, for example, a memory (not shown) storing a program for causing these elements to function, and a processing circuit (not shown) corresponding to a processor such as a CPU (Central Processing Unit) And the processor may function as these elements by executing a program.

<Control unit>
The control unit 41 controls the output of each of the plurality of inverters 42a and 42b. Specifically, the control unit 41 receives information on the heating temperature set by the operation unit 31 from the operation unit 31, and outputs each of the plurality of inverters 42a and 42b based on the received information on the heating temperature. Control.

  For example, the user sets the heating temperature of the first heating area A1 via the operation unit 31. The operation unit 31 transmits information of the set heating temperature to the control unit 41. The control unit 41 receives the information on the heating temperature of the first heating area A1 from the operation unit 31, and sets the output of the first inverter 42a based on the received information on the heating temperature. For example, the control unit 41 sets the frequency and the output time of the high frequency current supplied from the first inverter 42a to the first heating coil 23a. Next, the control unit 41 causes the first heating coil 23a to output a high frequency current based on the determined output.

  As described above, the control unit 41 controls the output of the first inverter 42 a based on the heating temperature of the first heating area A <b> 1 set by the operation unit 31. Similarly, the control unit 41 controls the output of the second inverter 42b based on the heating temperature of the second heating area A2 set by the operation unit 31.

  By such control, the control unit 41 individually separates the first heating area A1 heated by the first heat generating section 12a of the heating plate 10 and the second heating area A2 heated by the second heat generating section 12b. The temperature can be adjusted.

  Further, the control unit 41 controls the output of each of the plurality of inverters 42a and 42b based on the information of the temperature detected by the plurality of temperature detection units 24a and 24b. For example, while the heating plate 10 is being heated, the first temperature detection unit 24a detects temperature information of the first heat generating unit 12a, that is, temperature information of the first heating area A1. The temperature information detected by the first temperature detection unit 24 a is transmitted to the first temperature calculation unit 43 a of the control unit 41. The first temperature calculator 43a calculates the temperature of the first heat generator 12a based on the detected temperature information. The calculated temperature of the first heat generating unit 12 a is transmitted to the control unit 41. The control unit 41 compares the calculated temperature of the first heat generating unit 12 a with the heating temperature of the first heating area A <b> 1 set by the operation unit 31. The control unit 41 adjusts the output of the first inverter 42 a based on the comparison result so that the temperature of the first heat generating unit 12 a becomes equal to the heating temperature set by the operation unit 31.

  As described above, the control unit 41 controls the output of the first inverter 42a based on the temperature information of the first heating unit 12a detected by the first temperature detection unit 24a, that is, the temperature information of the first heating area A1. ing. Similarly, the control unit 41 controls the output of the second inverter 42b based on the temperature information of the second heat generating unit 12b detected by the second temperature detection unit 24b, that is, the temperature information of the second heating area A2. There is.

  With such control, the control unit 41 can easily realize the set heating temperature in the first heating area A1 and the second heating area A2, and can easily maintain the set heating temperature. .

  Further, the control unit 41 transmits, to the display unit 32, information such as the heating temperature of the first heating area A1 and the second heating area A2 set by the operation unit 31, a timer, and / or a course, for example. The display unit 32 displays the set heating temperature, the timer, and / or the information of the course based on the information received from the control unit 41.

  Further, the control unit 41 sets the temperature of the first heating area A1 and the second heating area A2 to a heating temperature based on the temperature information detected by the first temperature detection section 24a and the second temperature detection section 24b. If it judges that it has become, the notification unit 33 is controlled to notify the user. For example, when the preheating is completed, the control unit 41 may perform notification by sound with a buzzer or the like.

<Inverter>
The plurality of inverters 42 a and 42 b supply high frequency current to the plurality of heating coils 23 a and 23 b according to the output set by the control unit 41. FIG. 8 is a circuit diagram of a part of an exemplary control circuit of the induction heating cooker 1 according to the embodiment of the present invention. As shown in FIG. 8, the first inverter 42 a is connected to the first heating coil 23 a via the smoothing capacitor C <b> 1. The second inverter 42b is connected to the second heating coil 23b via the smoothing capacitor C1. The first heating coil 23a and the capacitor C2 are connected in parallel, and the second heating coil 23b and the capacitor C3 are connected in parallel.

  The plurality of inverters 42a and 42b have switching elements SW1 and SW2, respectively. In the embodiment, the first inverter 42a includes the first switching element SW1, and the second inverter 42b includes the second switching element SW2.

  Each of the first switching element SW1 and the second switching element SW2 is a switch that generates a high frequency current based on the pulse wave input from the control unit 41. That is, the first switching element SW1 and the second switching element SW2 are switches for supplying high frequency current to the first heating coil 23a and the second heating coil 23b from the first inverter 42a and the second inverter 42b, respectively. The first switching element SW1 and the second switching element SW2 use Insulated Gate Bipolar Transistors (IGBTs). When a pulse wave is input from the control unit 41, the IGBT converts a direct current supplied from an alternating current power supply via a DC converter into a high frequency current corresponding to a desired output. The IGBT converts a direct current into a high frequency current based on the pulse wave set by the control unit 41.

  The first inverter 42 a is turned on while the pulse wave is input from the control unit 41 to the first switching element SW 1. While the first inverter 42 a is turned on, the first switching element SW 1 is used to generate a high frequency current based on the pulse wave input from the control unit 41. The first inverter 42a supplies the generated high frequency current to the first heating coil 23a. The first inverter 42a is turned off when the pulse wave is not input from the control unit 41 to the first switching element SW1, and stops the supply of the high frequency current to the first heating coil 23a.

  Similarly, while the pulse wave is being input from the control unit 41 to the second switching element SW2, the second inverter 42b is turned on. The second inverter 42 b generates a high frequency current based on the pulse wave input from the control unit 41 using the second switching element SW 2. The second inverter 42b supplies the generated high frequency current to the second heating coil 23b. The second inverter 42b is turned off when the pulse wave is not input from the control unit 41 to the second switching element SW2, and stops the supply of the high frequency current to the second heating coil 23b.

  As described above, in the induction heating cooker 1, each of the plurality of inverters 42a and 42b uses one switching element (IGBT) to supply high-frequency current to one heating coil. With such a configuration, cost can be reduced as compared with a configuration in which one inverter uses two switching elements to supply high frequency current to a plurality of heating coils. Further, since the amount of heat generation can be suppressed, the heat sink for exhausting heat can be made smaller. As a result, the induction heating cooker 1 can be thinned.

<Temperature calculation unit>
The plurality of temperature calculation units 43a and 43b respectively calculate the temperatures of the plurality of heating areas A1 and A2 based on the information of the temperatures detected by the plurality of temperature detection units 24a and 24b. Specifically, the first temperature calculation unit 43a and the second temperature calculation unit 43b respectively receive the first heating area A1 and the second heating area from the first temperature detection section 24a and the second temperature detection section 24b, respectively. Receive temperature information. The first temperature calculation unit 43a and the second temperature calculation unit 43b calculate the respective temperatures of the first heating area A1 and the second heating area based on the information on the temperature. The first temperature calculation unit 43a and the second temperature calculation unit 43b transmit information of the calculated temperature to the control unit 41.

<Cooling fan>
As shown in FIG. 2, the cooling fan 51 is a turbo fan that blows cooling air into the main body 20. The cooling fan 51 blows air from the outside of the main body 20 to cool the plurality of heating coils 23 a and 23 b, the plurality of inverters 42 a and 42 b, and the control unit 41 housed in the main body 20. Specifically, the cooling fan 51 sucks air from the outside of the main body 20 from the lower surface opening 25 a and the side opening 25 b provided on one end side of the main body 20, and sends the air to the inside of the main body 20.

  FIG. 9 is a schematic diagram showing an internal configuration of an exemplary body. As shown in FIG. 9, the cooling fan 51 has a rotation axis CR <b> 1 extending in the thickness direction of the main body 20, that is, in the Z direction. The cooling fan 51 is attached to one end side in the longitudinal direction of the main body 20. The cooling fan 51 is attached to a fan casing 53 integrally formed with an attachment plate 52 to which the first heating coil 23a is attached.

<Fan casing>
FIG. 10 is a schematic partial configuration diagram showing an example of the configuration inside the main body around the cooling fan 51 disposed on one end side of the main body 20. As shown in FIG. FIG. 11 is another schematic partial configuration diagram showing an example of the configuration inside the main body around the cooling fan 51 disposed on one end side of the main body 20. As shown in FIG.

  As shown to FIGS. 9-11, the fan casing 53 is a case which accommodates the cooling fan 51 inside. An intake port 54 for taking in air is provided on the upper surface 53 a of the fan casing 53. On the other hand, the lower surface 53b of the fan casing 53 is closed by the second housing 21b as shown in FIG. That is, the lower surface 53b of the fan casing 53 is formed by the second housing 21b.

  As shown in FIGS. 9 and 10, the intake port 54 communicates with the lower surface opening 25a provided on the lower surface at one end side of the main body 20. Further, the intake port 54 communicates with the side opening 25 b provided on the side surface on one end side of the main body 20. Therefore, when the cooling fan 51 is driven, air outside the main body 20 is drawn from the lower surface opening 25a and the side surface opening 25b. As shown by arrow FL1 in FIG. 10, the air outside the main body 20 flows into the intake port 54 provided on the upper surface 53a of the fan casing 53 through the lower surface opening 25a and the side surface opening 25b.

  The lower surface opening 25 a is located above the lower surface 53 b of the fan casing 53. That is, the lower surface 53b of the fan casing 53 is located below the lower surface opening 25a. With such a configuration, air from the lower surface opening 25 a can easily flow into the air inlet 54 provided on the upper surface 53 a of the fan casing 53.

  The fan casing 53 has an air outlet 55 for blowing air from the cooling fan 51 to the first heating coil 23a on the side surface on which the first heating coil 23a is disposed. The air outlet 55 is provided below the lower surface of the mounting plate 52 to which the first heating coil 23a is attached. As a result, as shown by arrow FL2 in FIG. 10, the air from the cooling fan 51 is blown toward the first heating coil 23a through the blowing port 55.

  As described above, the cooling fan 51 sucks in the cooling air from the intake port 54 provided on the upper surface 53 a of the fan casing 53, and the air from the air vent 55 provided on the side surface of the fan casing 53 is the first heating coil. It is blowing air to 23a.

  With such a configuration, the amount of air blown into the main body 20 can be increased in order to cool the plurality of heating coils 23a and 23b, so that the cooling effect can be improved.

  Further, since the intake port 54 is provided on the upper surface 53a of the fan casing 53, the inflow of water can be suppressed. For example, even if there is water below the bottom of the main body 20, the air can be taken in from the air inlet 54 provided on the upper surface 53a of the fan casing 53, so water is less likely to be sucked into the air inlet 54. For this reason, it can suppress that water flows in from the inlet port 54 of the fan casing 53. FIG.

  Further, since the air is taken in from the intake port 54 provided on the upper surface 53 a of the fan casing 53, the lower surface 53 b of the fan casing 53 can be closed. Therefore, the cooling fan 51 can be disposed close to the bottom surface of the main body 20. That is, the height of the main body 20 can be lowered. As a result, according to the induction heating cooker 1, the thickness of the device can be reduced as compared with the configuration in which the intake port is provided on the lower surface of the fan casing. As a result, the induction heating cooker 1 can be miniaturized.

  In the inside of the main body 20, a partition rib 56 is provided which partitions an area in which the cooling fan 51 is disposed and an area in which the first heating coil 23a is disposed. The partition rib 56 separates a flow path in which the air flows from the outside of the main body 20 to the intake port 54 of the fan casing 53 and a flow path in which the air flows from the air outlet 55 of the fan casing 53 to the first heating coil 23a. There is. Specifically, the partition rib 56 is formed of a plate-like member extending from the upper surface of the mounting plate 52 to which the first heating coil 23 a is attached toward the upper surface of the main body 20.

  With such a configuration, the flow of air from the first heating coil 23 a side to the air intake port 54 of the fan casing 53 can be blocked by the partition rib 56. As a result, air warmed by the heat of the first heating coil 23a can be suppressed from being drawn into the air intake port 54.

  As shown in FIG. 11, in the inside of the main body 20, a drainage rib 57 extending in the thickness direction of the main body 20, that is, in the Z direction is formed in the flow path between the side opening 25b and the air intake 54 of the fan casing 53. ing. The drainage rib 57 is a plate-like member extending in the width direction of the main body 20, that is, in the X direction. The upper surface 57 a of the drainage rib 57 is formed at a position higher than the air inlet 54 of the fan casing 53.

  With such a configuration, when water intrudes into the interior of the main body 20 from the outside of the main body 20 through the side opening 25b, the drain rib 57 can suppress water from flowing into the intake port 54. .

  Moreover, the connection terminal 27 which connects the power supply cord which supplies electric power to the induction heating cooker 1 is provided in the side of the one end side of the main body 20. Thus, by not providing the connection terminal 27 on the other end side where the exhaust ports 26a and 26b are provided, it is possible to suppress the heating of the connection terminal 27 due to the air warmed inside the main body 20.

[Heating control]
Next, exemplary heating control of the induction heating cooker 1 will be described.

  FIG. 12A is a diagram showing an example of heating control of the induction heating cooker 1 according to the embodiment of the present invention. 12A shows the control of the output of the first inverter 42a by the control unit 41, the control of the output of the second inverter 42b, and the entire output. The total output means the sum of the output of the first inverter 42a and the output of the second inverter 42b. Further, the control shown in FIG. 12A shows the control of the outputs of the first inverter 42a and the second inverter 42b when heating both the first heating area A1 and the second heating area A2 of the heating plate 10 at the same heating temperature. .

  As shown in FIG. 12A, in the case where both the first heating area A1 and the second heating area A2 of the heating plate 10 are heated at the same heating temperature, as shown in FIG. 12A, both the first inverter 42a and the second inverter 42b Set the output to P1. P1 is, for example, the output of the inverter calculated based on the heating temperature set by the operation unit 31. That is, P1 is an output corresponding to the desired heating temperature set by the user.

  Next, the control unit 41 sequentially switches the output of the first inverter 42a and the output of the second inverter 42b by sequentially switching on and off of the first inverter 42a and the second inverter 42b. Thereby, the supply of the high frequency current from the first inverter 42a to the first heating coil 23a and the supply of the high frequency current from the second inverter 42b to the second heating coil 23b are sequentially switched. As a result, the first heating area A1 and the second heating area A2 are sequentially heated by sequentially induction heating the first heat generating portion 12a and the second heat generating portion 12b. Thereby, the first heating area A1 and the second heating area A2 are heated to the same temperature.

  In the embodiment, the control unit 41 controls the two inverters 42a and 42b, and alternately switches the output of the first inverter 42a and the output of the second inverter 42b. That is, the control unit 41 alternately switches the supply of the high frequency current from the first inverter 42a to the first heating coil 23a and the supply of the high frequency current from the second inverter 42b to the second heating coil 23b.

  Specifically, when heating is started, the control unit 41 turns on the first inverter 42a by inputting a pulse wave to the first switching element SW1. While the first inverter 42 a is on, the first inverter 42 a generates a high frequency current based on the pulse wave input from the control unit 41. The first inverter 42a supplies the generated high frequency current to the first heating coil 23a. Here, the control unit 41 starts the output of the first inverter 42a from 0 and gradually raises it to P1.

  When the output of the first inverter 42a reaches P1, the control unit 41 stops the input of the pulse wave to the first switching element SW1, and switches the first inverter 42a from on to off. Thereby, the supply of the high frequency current from the first inverter 42a to the first heating coil 23a is stopped. That is, the output of the first inverter 42a is stopped.

  Next, the control unit 41 switches the second inverter 42b from off to on by inputting a pulse wave to the second switching element SW2. While the second inverter 42 b is on, the second inverter 42 b generates a high frequency current based on the pulse wave input from the control unit 41. The second inverter 42b supplies the generated high frequency current to the second heating coil 23b. Here, the control unit 41 starts the output of the second inverter 42b from 0 and gradually raises it to P1.

  When the output of the second inverter 42b reaches P1, the control unit 41 stops the input of the pulse wave to the second switching element SW2, and switches the second inverter 42b from on to off. Thereby, the supply of the high frequency current from the second inverter 42b to the second heating coil 23b is stopped. That is, the output of the second inverter 42b is stopped.

  In the heating control shown in FIG. 12A, the output of the first inverter 42a and the output of the second inverter 42b described above are sequentially switched to sequentially heat the first heating coil 23a and the second heating coil 23b.

  Thus, the control unit 41 switches the output of the first inverter 42 a and the output of the second inverter 42 b alternately to make the entire output P 1. Thus, the entire surface of the heating plate 10 can be uniformly heated at a predetermined heating temperature.

  Also, by alternately switching the output of the first inverter 42a and the output of the second inverter 42b, the supply of the high frequency current from the first inverter 42a and the supply of the high frequency current from the second inverter 42b are alternately performed. There is. That is, when the high frequency current is supplied from the first inverter 42a to the first heating coil 23a, the supply of the high frequency current from the second inverter 42b to the second heating coil 23b is stopped. On the other hand, when the high frequency current is supplied from the second inverter 42b to the second heating coil 23b, the supply of the high frequency current from the first inverter 42a to the first heating coil 23a is stopped.

  Further, since the high frequency current is not simultaneously supplied to the first heating coil 23a and the second heating coil 23b, the electromagnetic wave generated from the first heating coil 23a and the electromagnetic wave generated from the second heating coil 23b do not interfere with each other. For this reason, it can suppress that the interference sound by interference of these electromagnetic waves arises.

  When both the first inverter 42a and the second inverter 42b are turned on to simultaneously supply a high frequency current to the plurality of heating coils 23a and 23b, interference noise may occur. For example, when the output of the first inverter 42a and the output of the second inverter 42b are different, the frequency of the high frequency current is different, and interference noise may be generated due to interference of electromagnetic waves generated from the respective inverters. is there. According to the induction heating cooker 1, high frequency current is alternately supplied to the first heating coil 23a and the second heating coil 23b in order to switch the first inverter 42a and the second inverter 42b on and off alternately. For this reason, high frequency current is not simultaneously supplied to the plurality of heating coils 23a and 23b, and it is possible to suppress the generation of interference noise. That is, according to the induction heating cooker 1, generation | occurrence | production of the interference sound which a user feels unpleasant can be suppressed.

  In addition, when the first inverter 42a is switched from off to on, the control unit 41 starts the output of the first inverter 42a from 0 each time and gradually raises it to P1. Also, when the second inverter 42 b switches from off to on, the control unit 41 starts the output of the second inverter 42 b from 0 each time, and gradually raises it to P 1.

  Thus, the control unit 41 reduces the output at the start of the output of the first inverter 42a and the second inverter 42b each time the output of the first inverter 42a and the output of the second inverter 42b are switched. By controlling in this manner, when the output of the first inverter 42a and the output of the second inverter 42b are switched, the load on the first inverter 42a and the second inverter 42b can be reduced.

  FIG. 12B is a diagram showing another example of the heating control of the induction heating cooker 1 according to the embodiment of the present invention. In the heating control shown in FIG. 12B, the control unit 41 sets the next output based on the previous output information of the first inverter 42a and the second inverter 42b. The heating control shown in FIG. 12B is the same as the heating control shown in FIG. 12A in that the control unit 41 sequentially switches the output of the first inverter 42a and the output of the second inverter 42b.

  As shown in FIG. 12B, the control unit 41 stores the output information of the first inverter 42a when the first inverter 42a is on and the output information of the second inverter 42b when the second inverter 42b is on. . The control unit 41 controls the outputs of the first inverter 42 a and the second inverter 42 b based on the stored output information.

  For example, when heating is started, the control unit 41 inputs a pulse wave to the first switching element SW1, and turns on the first inverter 42a. Thereby, the supply of the high frequency current from the first inverter 42a to the first heating coil 23a is started. When the supply of the high frequency current is started, the control unit 41 gradually increases the output of the first inverter 42a from 0 to P1.

  Further, the control unit 41 stores the output information of the first inverter 42a when the first inverter 42a is on. The output information includes, for example, the output of the first inverter 42 a and the output time.

  Next, the control unit 41 sets the output of the first inverter 42a when the first inverter 42a is turned on next, based on the stored output information. The details of the setting of the output of the inverter based on the output information will be described in “Details of heating control” described later.

  In the stored output information, when the first output of the first inverter 42a is P1 in the stored output information, the control unit 41 sets the second output of the first inverter 42a to be output next to P1. Specifically, the control unit 41 sets the second output of the first inverter 42a not to start from 0 and gradually increase to P1, but to start from P1 from the beginning.

The control unit 41, in the stored output information, based on the first output time ts ₁ of the first inverter 42a of previous sets a second output time ts ₂ of the next first inverter 42a. The output time is the time during which the pulse wave is input to the switching element and the inverter is turned on, that is, the time during which the inverter is supplying high frequency current to the heating coil.

In the heating control shown in FIG. 12B, when the first inverter 42a is turned on for the second time and thereafter, the control unit 41 sets P1 constant without decreasing the output of the first inverter 42a. The control unit 41 has set the output time _{ts 1, ts 2, ts 3} all the same time.

The control unit 41 also performs the same control as the control of the output of the first inverter 42 a with regard to the control of the output of the second inverter 42 b. That is, when the second inverter 42b is turned on for the second time and thereafter, the control unit 41 sets P1 constant without reducing the output of the second inverter 42b. In addition, the control unit 41 sets the output times ts ₁₁ , ts ₁₂ , and ts ₁₃ to the same time.

  By controlling in this manner, the high frequency current can be efficiently output from the first inverter 42a and the second inverter 42b, and the heating plate 10 can be efficiently heated.

  In the heating control shown in FIG. 12B, the control unit 41 does not reduce the outputs of the first inverter 42a and the second inverter 42b when the first inverter 42a and the second inverter 42b are turned on for the second time and thereafter. Although an example in which P1 is constant has been described, the present invention is not limited to this. For example, the control unit 41 may change the next output based on the previous output of the first inverter 42a and the second inverter 42b.

Further, in the heating control shown in FIG. 12B, the control unit 41 sets all the output times ts ₁ , ts ₂ and ts ₃ of the first inverter 42 a to the same time, and the output times ts ₁₁ and ts _{12 of} the second inverter 42 b. , Ts ₁₃ are all set to the same time, but the present invention is not limited to this. For example, the control unit 41 sets the next output times ts ₂ and ts ₁₂ to times different from the previous output times ts ₁ and ts ₁₁ based on the previous outputs of the first inverter 42 a and the second inverter 42 b. It is also good.

[Details of heating control]
Next, an example of detailed heating control of the induction heating cooker 1 will be described.

  FIG. 13 is a diagram showing an example of detailed heating control of the induction heating cooker 1 according to the embodiment of the present invention. FIG. 13 illustrates an example of control of pulse waves by the control unit 41. FIG. 13 shows the first pulse wave input to the first switching element SW1 of the first inverter 42a and the second pulse wave input to the second switching element SW2 of the second inverter 42b.

  As shown in FIG. 13, the control unit 41 inputs the first pulse wave to the first switching element SW1 of the first inverter 42a and the input of the second pulse wave to the second switching element SW2 of the second inverter 42b. And alternately. Thereby, the control unit 41 alternately supplies the high frequency current from the first inverter 42a to the first heating coil 23a and the supply of the high frequency current from the second inverter 42b to the second heating coil 23b. .

The control of the first pulse wave of the control unit 41 that controls the output of the first inverter 42a will be described. The control unit 41 sets the output of the first inverter 42 a based on, for example, the heating temperature set by the operation unit 31. Specifically, the control unit 41 sets the on-time of the first pulse wave input to the first switching element SW1 of the first inverter 42a. Control unit 41, a duty of the first pulse wave on / off as certain conditions, by setting the on-time of the first pulse wave, and sets the first frequency f ₁ of the first pulse wave . Further, the control unit 41 sets the first output time ts ₁ based on the on time of the first pulse wave.

The control unit 41 turns on the first inverter 42a by inputting the first pulse wave to the first switching element SW1. During the first output time ts ₁ of the first inverter 42a is turned on, the first inverter 42a, based on the first pulse wave input from the control unit 41, a high frequency direct current by the first switching element SW1 Convert to current. Thereby, the first inverter 42a supplies a high frequency current to the first heating coil 23a. At this time, the control unit 41 stores the last ON-time t ₁ of the first pulse wave at the first output time ts _1.

Control unit 41, based on the last on-time t ₁ of the first pulse wave at the first output time ts _1, then the second first pulse wave at the output time ts ₂ when the first inverter 42a is turned on to set up the first on-time t ₂ of.

In the embodiment, the control unit 41, the first on-time t ₂ of the first pulse wave at the second output time ts ₂ of the next time first inverter 42a is turned on, first at the first output time ts ₁ same to set the last of on-time t ₁ of 1 pulse wave.

Thus, the control unit 41 can then be first inverter 42a sets the second frequency f ₂ of the second first pulse wave at the output time ts ₂ when turned on. In the embodiment, the control unit 41 has set the second frequency f ₂ the same as the first frequency f _1.

The control unit 41, based on the first on-time _{t 2} of the first pulse wave at the second output time ts _2, sets a second output time ts _2. In embodiments, the first on-time t ₂ of the first pulse wave at the second output time ts ₂ have been set equal to the last on-time t ₁ of the first pulse wave at the first output time ts ₁ Therefore, the second output time ts ₂ is set to the same time as ts ₁ first output time.

Thus, the control unit 41, the first pulse wave when the first inverter 42a last time based on the last on-time t ₁ of the first pulse wave when on, then the first inverter 42a is turned on The first on-time t ₂ is set. Thus, the first inverter 42a can output the next first inverter 42a based on the previous output information. As a result, the first heating area A1 of the heating plate 10 can be efficiently heated.

  The control of the second pulse wave by the control unit 41 that controls the output of the second inverter 42 b is also similar to the control of the first pulse wave.

The control unit 41 sets the on time of the second pulse wave input to the second switching element SW2 of the second inverter 42b. Next, the control unit 41 turns on the second inverter 42b by inputting the second pulse wave to the second switching element SW2. During the first output time ts ₁₁ of the second inverter 42b is turned on, the second inverter 42b, based on the second pulse wave input from the control unit 41, a high frequency direct current by the second switching element SW2 Convert to current. Thereby, the second inverter 42b supplies a high frequency current to the second heating coil 23b. At this time, the control unit 41 stores the last ON-time _{t 11} of the second pulse wave at the first output time _{ts 11.}

Control unit 41, based on the last on-time _{t 11} of the second pulse wave at the first output time _{ts 11,} sets the first on-time _{t 12} of the second pulse wave at the second output time _{ts 12.} Thus, the control unit 41 sets the second frequency _{f 12} of the second pulse wave of the second inverter 42b at a second output time _{ts 12.}

In the embodiment, the control unit 41 includes a first frequency _{f 11} of the second pulse wave at the first output time _{ts 11,} and a second pulse wave second frequency _{f 12} of the same at the second output time _{ts 12} It is set. The control unit 41, a second output time _{ts 12,} are set at the same time as the first output time _{ts 11.}

  Thus, the control unit 41 stores, as output information, the last on-time of the pulse wave in the previous output time, and the first on-time of the next pulse wave based on the last on-time of the pulse wave. It is set. By performing such control, the output information of the previous time can be taken over and the output of the inverter can be controlled, so that each heating region of the heating plate 10 can be efficiently heated.

In the heating control shown in FIG. 13, the control unit 41 sets the first output times ts ₁ and ts ₁₁ and the second output times ts ₂ and ts ₁₂ in the first inverter 42 a and the second inverter 42 b to the same. Although the example to set was demonstrated, it is not limited to this. For example, when the setting of the heating temperature is changed during heating, the control unit 41 sets the first output times ts ₁ and ts ₁₁ and the second output times ts ₂ and ts ₁₂ to different times. May be

Also, the output times ts ₁ and ts ₂ of the first inverter 42 a may be different from the output times ts ₁₁ and ts _{12 of} the second inverter 42 b. The output times ts ₁ , ts ₂ , ts ₁₁ and ts ₁₂ may be set according to the magnitudes of the outputs of the first inverter 42 a and the second inverter 42 b.

Further, the control unit 41 compares the outputs of the plurality of inverters 42a and 42b in the drive cycles tc ₁ and tc _{2 at which} the plurality of inverters 42a and 42b are switched on and off, and based on the difference between the outputs, the drive cycle tc ₁ , Tc ₂ may be adjusted.

The driving cycles tc ₁ and tc ₂ mean a period from when the first inverter 42 a is turned on to when the first inverter 42 a is turned on next. In other words, the drive cycles tc ₁ and tc ₂ mean the period from the input of the first pulse wave to the next input of the first pulse wave. As shown in FIG. 13, the driving period tc ₁ is a period obtained by summing the first output time of the first pulse wave ts ₁ and the first output time _{ts 11} of the second pulse wave. The driving period tc ₂ is a period in which the sum of second output time of the first pulse wave ts ₂ and a second output time _{ts 12} of the second pulse wave.

For example, the control unit 41 compares the outputs of the plurality of inverters 42a and 42b (that is, the consumption output of the induction heating cooker, and outputs per second) in the drive cycles tc ₁ and tc ₂ and outputs the outputs (that is, the induction When the difference between the output of the heating cooker and the output per second is relatively large, the drive cycles tc ₁ and tc ₂ may be extended as compared to the case where the difference is relatively small. Alternatively, the control unit 41 compares the outputs of the plurality of inverters 42 a and 42 b in the drive cycles tc ₁ and tc ₂ , and when the difference between the outputs is relatively small, the drive cycle compared to when relatively large. tc ₁ and tc ₂ may be shortened.

  By such control, it is possible to suppress an erroneous operation of the device due to the influence of the device such as illumination around the plurality of heating coils 23a and 23b.

In the heating control shown in FIG. 13, the control unit 41 sets the first on-times t ₂ and t ₁₂ of the pulse wave at the second output times ts ₂ and ts _{12 to} the pulses at the first output times ts ₁ and ts ₁₁ . been described, each configured the same as the last on-time t _1, t ₁₁ waves, but is not limited thereto. The controller 41 controls the first on time t ₂ , t ₁₂ of the pulse wave at the second output time ts ₂ , ts _{12 and} the last on time t ₁ , t ₁ of the pulse wave at the first output time ts ₁ , ts _{11 11} may be set differently.

For example, in the first output time ts ₁ of the first inverter 42a, illustrating a case where not reached the target output P1 set by the control unit 41. In this case, the control unit 41, the first inverter 42a, the first on-time _{t 2} of the first pulse wave at the second output time ts _2, the last on-time of the first pulse wave at the first output time ts ₁ It may be set longer than t ₁ .

  By such control, the inverter can be set to an appropriate output, and can be quickly heated to a desired heating temperature.

[effect]
According to the induction heating cooker 1 which concerns on Embodiment 1, the following effects can be produced.

  In the induction heating cooker 1, the heating plate 10 has a plurality of heat generating parts 12a, 12b. In addition, a plurality of heating coils 23a and 23b are respectively disposed in a region where the plurality of heat generating portions 12a and 12b are projected when viewed from the thickness direction of the heating plate 10. With such a configuration, a plurality of heating areas A1 and A2 respectively heated by the plurality of heat generating portions 12a and 12b are formed on one heating plate 10, and the plurality of heating areas A1 and A2 are individually heated. Can.

  Further, the heating temperature of each of the plurality of heating areas A1 and A2 can be adjusted individually by the control unit 41. For this reason, according to the induction heating cooker 1, the heating temperature set by the user can be realized in each of the plurality of heating areas A1 and A2. As a result, the user can heat the food at the set heating temperature in each of the plurality of heating areas A1 and A2. Therefore, according to the induction heating cooker 1, the convenience can be improved.

  The plurality of heat generating portions 12 a and 12 b are formed of a metal material having a higher electrical resistance value than the metal material forming the heat transfer portion 11. With such a configuration, the plurality of heat generating portions 12a and 12b can be easily inductively heated, and the heat transfer portion 11 can be less likely to be inductively heated. Thereby, the plurality of heating areas A1 and A2 can be separated to facilitate temperature control, and thus convenience can be further improved.

  The heating plate 10 has a symmetrical shape with respect to a center line CL1 of the heating plate 10 extending in the width direction. The plurality of heat generating portions 12 a and 12 b are provided symmetrically with respect to the center line CL 1 of the heating plate 10. With such a configuration, the heating plate 10 can be mounted on the main body 20 without distinction in the left-right direction. As a result, the convenience is further improved.

  The heating plate 10 has a positioning portion 13 which protrudes from the lower surface of the heating plate 10 toward the top plate 22 and is located at the outer edge 22 a of the top plate 22. With such a configuration, when the heating plate 10 is placed on the top plate 22, the heating plate 10 can be easily positioned on the top plate 22. As a result, the convenience is further improved.

  The heating plate 10 has a rib 14 projecting from the lower surface of the heating plate toward the top plate 22 along the lengthwise direction of the heating plate 10 and located at the outer edge 22 a of the top plate 22. Such a configuration can prevent the heating plate 10 from warping due to thermal deformation. In addition, heat accumulation in the ribs 14 can improve the heat retention of the outer edge of the heating plate 10. Furthermore, it is possible to suppress wind from flowing below the heating plate 10 and to improve the heat retention.

  The lower end 14 a of the rib 14 is located below the upper surface 22 b of the top plate 22 and above the lower surface 22 c of the top plate 22. With such a configuration, a gap S1 can be formed between the lower end 14a of the rib 14 and the upper surface of the main body 20. That is, since the rib 14 does not contact the main body 20, it is possible to suppress the conduction of heat from the rib 14 to the main body 20.

  The heating plate 10 has legs 16 extending from the lower surface of the heating plate 10 to the top plate 22 only on the outside of the plurality of heat generating parts 12 a and 12 b. With such a configuration, the heating plate 10 can be stably placed on the top plate 22.

  The heating plate 10 can be cooked across a plurality of heating areas A1 and A2 heated by the plurality of heat generating parts 12a and 12b, and has a partition part 15 that divides the plurality of heating areas A1 and A2. With such a configuration, the food can be heated across the plurality of heating areas A1 and A2, while the food is partitioned by the partition unit 15 and the food is heated in each of the plurality of heating areas A1 and A2 You can also. As a result, the convenience is further improved.

  The partition portion 15 is a recess provided on the upper surface of the heating plate 10 along a center line CL1 extending in the width direction of the heating plate 10 when viewed from the thickness direction of the heating plate 10. With such a configuration, since the food can be easily moved between the plurality of heating areas A1 and A2, the food can be more easily heated across the plurality of heating areas A1 and A2. As a result, the convenience is further improved.

  The ribs 14 are located inside the outer surface 10 a of the heating plate 10. With such a configuration, the ribs 14 can be provided without impairing the appearance of the heating plate 10.

Example 1
FIG. 14 is a graph showing an example of an experimental result when a heating experiment is performed in the induction heating cooker according to the embodiment of the present invention. The graph shown in FIG. 14 shows the first heating area A1 when the first heating area A1 of the heating plate 10 is heated to the first target heating temperature Tg1 and the second heating area A2 is heated to the second target heating temperature Tg2. And the results of measuring the temperature in the second heating area A2. The first target heating temperature Tg1 is 250 ° C., and the second target heating temperature Tg2 is 90 ° C. The first target heating temperature Tg1 and the second target heating temperature Tg2 are heating temperatures set by the operation unit 31.

  As shown in FIG. 14, the measurement temperature of the first heating area A1 reaches the first target heating temperature Tg1 in about 200 seconds, and maintains the first target heating temperature Tg1. In addition, the measurement temperature of the second heating area A2 also reaches the second target heating temperature Tg2 in about 200 seconds, and maintains the second target heating temperature Tg2.

  As described above, according to the induction heating cooker 1, the heating temperature is adjusted to the first target heating temperature Tg1 and the second target heating temperature Tg2 with high accuracy in the first heating area A1 and the second heating area A2, respectively. can do. That is, even if the left and right heating temperatures differ between the first heating area A1 and the second heating area A2, the temperatures of the heating areas A1 and A2 can be adjusted with high accuracy.

  Moreover, according to the induction heating cooker 1, the heating plate 10 can be efficiently heated, and can be heated to a desired heating temperature in a short time.

  Further, according to the induction heating cooker 1, since the temperature is controlled while detecting the temperatures of the first heating area A1 and the second heating area A2, the temperatures of the first heating area A1 and the second heating area A2 are respectively The first target heating temperature Tg1 and the second target heating temperature Tg2 can be maintained.

  In the embodiment, the heating plate 10 is described as a thin plate flat plate, but is not limited thereto. For example, the heating plate 10 may be a plate having a plurality of hemispherical recessed portions, a so-called grilled plate, a plate having a plurality of rectangular recessed portions, or a plate combining these plates. The combined plate may be, for example, a plate in which the first heating area A1 is flat, and the second heating area A2 may be a Takoyaki plate. Further, the shape of the heating plate 10 when viewed from the thickness direction is not limited to the rectangular shape. For example, the shape of the heating plate 10 when viewed in the thickness direction may be square, circular, or elliptical.

  Although the heating plate 10 demonstrated the example which has two heat-emitting part 12a, 12b in embodiment, it is not limited to this. The heating plate 10 may have two or more heat generating parts. Moreover, although the some heat-emitting part 12a, 12b demonstrated the example formed in cyclic | annular form, it is not limited to this. The shape of the plurality of heat generating portions 12a and 12b may be, for example, a circle, an ellipse, a triangle, a square, a rectangle, or a polygon.

  Moreover, although several heat-emitting part 12a, 12b demonstrated the example formed in the same size and the same shape, it is not limited to this. For example, the plurality of heat generating portions 12a and 12b may be formed in different sizes and different shapes, respectively.

  In the embodiment, an example is described in which the heating plate 10 has a left-right symmetrical shape with respect to the center line CL1 extending in the width direction, but is not limited thereto. Further, although the example in which the plurality of heat generating portions 12a and 12b are provided symmetrically with respect to the center line CL1 is also described, the present invention is not limited to this. For example, when the heating plate 10 is attached to the main body 20 by forming the heating plate 10 and the plurality of heat generating portions 12 a and 12 b so as to have different left and right shapes, the mounting direction can be fixed. This can prevent the heating plate 10 from being attached to the main body 20 in the wrong direction.

  Although heating plate 10 explained an example which has a plurality of positioning parts 13 in an embodiment, it is not limited to this. The heating plate 10 may have one or more positioning portions 13. Moreover, although the several positioning part 13 demonstrated the example formed in the corner | angular part of the heating plate 10, it is not limited to this. The plurality of positioning portions 13 may be located at the outer edge of the top plate 22 placed on the main body 20.

  Moreover, although the heating plate 10 demonstrated the example positioned on the top plate 22 by the positioning part 13, it is not limited to this. For example, the heating plate 10 may be positioned by a frame attached to the outer edge of the main body 20.

  FIG. 15: is a schematic block diagram of an example of the state which attached the flame | frame 60 to the induction heating cooker 1 which concerns on embodiment of this invention. As shown in FIG. 15, the frame 60 is disposed to surround the outer edge of the heating plate 10. In addition, the frame 60 has a frame leg 61 that extends below the top plate 22 and contacts the outer edge of the main body 20 on which the top plate 22 is placed. In the example shown in FIG. 15, the frame 60 has a plurality of frame legs 61 in contact with a plurality of corners of the main body 20. With such a configuration, when the heating plate 10 is disposed inside the frame 60, the outer edge of the heating plate 10 contacts the inner wall of the frame 60. Thus, the heating plate 10 can be positioned by the frame 60 in a state in which the heating plate 10 is placed on the top plate 22.

  In the embodiment, although the heating plate 10 has been described for the example having the plurality of ribs 14, it is not limited thereto. The heating plate 10 may have one or more ribs 14. Moreover, although the rib 14 demonstrated the example integrally formed with the positioning part 13, it is not limited to this. The rib 14 may be formed of a member separate from the positioning portion 13.

  Although the partition part 15 demonstrated the example formed by the recessed part in embodiment, it is not limited to this. The partition part 15 may be formed of a convex part, for example. With such a configuration, the user can cook without mixing the food to be heated in the first heating area A1 and the food to be heated in the second heating area A2.

  Moreover, although the partition part 15 demonstrated the example provided along centerline CL1 extended in the width direction of the heating plate 10, it is not limited to this. The partition part 15 should just be able to partition several heating area | region A1, A2, and should just be provided in the upper surface of the heating plate 10 between several heat-emitting part 12a, 12b.

  In the embodiment, the heating plate 10 has been described as an example having a plurality of cylindrical legs 16, but is not limited thereto. For example, the legs 16 may have an oval shape or a polygonal shape.

  In the embodiment, the first heating coil 23a and the second heating coil 23b are respectively in a one-to-one correspondence with the area where the first heat generating portion 12a and the second heat generating portion 12b are projected when viewed from the thickness direction of the heating plate 10. Although the example arrange | positioned oppositely was demonstrated, it is not limited to this. A plurality of heating coils may be disposed to face each of the first heat generating portion 12a and the second heat generating portion 12b. For example, a plurality of first heating coils 23a may be arranged concentrically in a region where the first heat generating portion 12a is projected. Similarly, a plurality of second heating coils 23b may be arranged concentrically in a region where the second heat generating portion 12b is projected.

  Although a plurality of temperature detection parts 24a and 24b explained an example arranged at the center of a plurality of heating coils 23a and 23b by an embodiment, it is not limited to this.

  In the embodiment, an example in which the opening is the lower surface opening 25a and the side surface opening 25b has been described, but is not limited thereto. The opening may be one of the lower surface opening 25a and the side surface opening 25b. Similarly, although the exhaust port demonstrated the example which is the lower surface exhaust port 26a and the side surface exhaust port 26b, it is not limited to this. The exhaust port may be any one of the lower surface exhaust port 26a and the side surface exhaust port 26b.

  In the embodiment, the cooling fan 51 has been described as an example of a turbo fan, but is not limited thereto. The cooling fan 51 may be a fan capable of taking in air from the air inlet 54 provided on the upper surface 53 a of the fan casing 53 and blowing the air from the air outlet 55 provided on the side surface of the fan casing 53.

  In the embodiment, the lower surface 53b of the fan casing 53 has been described as an example formed by the second housing 21b, but is not limited thereto. The fan casing 53 may be formed of an integral member including the lower surface 53b. The lower surface 53b of the fan casing 53 may be formed of a member different from the second housing 21b, or may be formed of a combination of the second housing 21b and another member.

  While the invention has been fully described in connection with the preferred embodiments with reference to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art. Such variations and modifications are to be understood as included within the scope of the present invention as set forth in the appended claims, unless they depart therefrom.

  The induction heating cooker according to the present invention is useful for an induction heating cooker placed on, for example, a tabletop or a gas stand because it can improve the convenience of the user in cooking.

DESCRIPTION OF SYMBOLS 1 induction heating cooker 10 heating plate 10a outer side 11 heat-transfer part 12a exothermic part (1st exothermic part)
12b Heating part (second heating part)
13 Positioning portion 14 Rib 14a Lower end 15 Partition portion 16 Leg portion 20 Main body 21a First casing 21b Second casing 22 Top plate 22a Outer edge 22b Upper surface 22c Lower surface 23a Heating coil (1st heating coil)
23b Heating coil (second heating coil)
24a Temperature detection unit (first temperature detection unit)
24b Temperature detection unit (second temperature detection unit)
25a Bottom opening (opening)
25b side opening (opening)
26a Bottom exhaust vent (vent)
26b Side exhaust (outlet)
27 connection terminal 31 operation unit 32 display unit 33 notification unit 40 control board 41 control unit 42 a inverter (first inverter)
42b Inverter (2nd inverter)
43a Temperature calculation unit (first temperature calculation unit)
43b Temperature calculation unit (second temperature calculation unit)
Reference Signs List 51 cooling fan 52 mounting plate 53 fan casing 53a upper surface 53b lower surface 54 intake port 55 air outlet 56 partition rib 57 drain rib 57a upper surface 58 through hole 60 frame 61 frame leg portion

Claims (11)

A heating plate having a plurality of heat generating parts to be inductively heated, and a heat transfer part that conducts heat generated by the plurality of heat generating parts;
A top plate on which the heating plate is placed;
And a plurality of heating coils disposed below the top plate and disposed in a region where the plurality of heating portions are projected when viewed from the thickness direction of the heating plate, and inductively heating the plurality of heating portions, ,
A plurality of inverters for supplying a high frequency current to each of the plurality of heating coils;
A control unit configured to control an output of each of the plurality of inverters;
Equipped with an induction heating cooker.   The induction heating cooker according to claim 1, wherein the plurality of heat generating parts are formed of a metal material having a higher electric resistance value than the metal material forming the heat transfer part. The heating plate has a symmetrical shape with respect to a center line of the heating plate extending in the width direction,
The plurality of heat generating portions are provided symmetrically with respect to the center line of the heating plate.
The induction heating cooker of Claim 1 or 2.   The induction heating method according to any one of claims 1 to 3, wherein the heating plate has a positioning portion that protrudes from the lower surface of the heating plate toward the top plate and is located at the outer edge of the top plate. vessel.   The heating plate according to any one of claims 1 to 4, wherein the heating plate has a rib projecting from the lower surface of the heating plate toward the top plate along the lengthwise direction of the heating plate and located at the outer edge of the top plate. Induction heating cooker according to any one of the preceding claims.   The induction heating cooker according to claim 5, wherein the lower end of the rib is located below the upper surface of the top plate and above the lower surface of the top plate.   The induction heating cooker according to any one of claims 1 to 6, wherein the heating plate has legs extending from the lower surface of the heating plate to the top plate only on the outside of the plurality of heat generating parts.   The heating plate according to any one of claims 1 to 7, wherein the heating plate is capable of cooking across a plurality of heating areas heated by the plurality of heat generating parts, and has a partition part partitioning the plurality of heating areas. The induction heating cooker as described in a term.   The induction heating / cooking method according to claim 8, wherein the partition portion is a recess provided on the upper surface of the heating plate along a center line extending in the width direction of the heating plate when viewed from the thickness direction of the heating plate. vessel. And a frame disposed at an outer edge of the heating plate.
The induction heating cooker according to any one of claims 1 to 9, wherein the frame has frame legs extending downward from the top plate and in contact with the outer edge of the main body on which the top plate is placed.   The induction heating cooker according to claim 5, wherein the rib is located inside the outer surface of the heating plate.

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