JP2010198753A - Induction heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an induction heating cooker capable of efficiently heating an object to be heated without magnetically saturating a ferrite member. <P>SOLUTION: This induction heating cooker includes a plurality of connected coils disposed like a lattice, a plurality of bases disposed like a lattice in the lower parts of the respective connected coils, a plurality of cores passing through the centers of the respective connected coils and extending from the bases, links extending in at least either one of a longitudinal direction and a lateral direction to connect the bases adjacent to each other, and a high frequency power supply to supply a high frequency current to each of the connected coils. The base, the core, and the link are made of a high magnetic permeability material. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an induction heating cooker having a plurality of small-diameter heating coils, and more particularly to an induction heating cooker that can improve heating efficiency using ferrite.

  An induction heating cooker such as a so-called IH cooking heater supplies an eddy current to a heated object such as a pan (cooking utensil) by supplying a high frequency current of several tens kHz from an inverter circuit to a spirally wound heating coil. And the cooking utensil itself is heated.

  For example, a conventional electromagnetic cooker described in Patent Document 1 generally includes one or two heating coils, a plurality of rod-shaped ferrites arranged radially below the heating coils (see FIG. 2), and heating. And a top plate made of glass or the like disposed above the coil. In general, ferrite is a general term for ceramics mainly composed of iron oxide. In the present specification, the term “ferrite” refers to a member that is non-conductive, has high magnetic permeability, and has ferromagnetism. The plurality of radially extending rod-like ferrites can reduce the magnetic resistance of the magnetic path generated by the heating coil and increase the magnetic field generated by the heating coil without forming eddy currents inside. Therefore, providing the rod-shaped ferrite is extremely useful in that the heating efficiency of the pan can be substantially increased.

  However, in the rod-shaped ferrites radially arranged in Patent Document 1 (FIGS. 1 and 2 of Patent Document 1), the magnetic flux passing through the radially inner and outer protrusions constitutes a closed magnetic circuit, but per unit area The magnetic flux intensity, that is, the magnetic flux density, is greater at the inner protrusion than at the outer protrusion. In addition, when a central ferrite member that connects a plurality of inner protrusions is provided (not shown), the magnetic flux density inside thereof is further increased.

  In Patent Document 1, two heating coils are used. However, in Patent Document 2, six small-diameter coils are used, and similarly, ferrite members arranged radially are suggested (see FIGS. 1 and 2). . At this time, since the radial yoke core disposed below the coil intersects at the center portion, when a high-frequency current having an opposite phase is supplied to the opposing coil, the magnetic flux density at the center portion of the yoke core becomes extremely large.

Japanese Patent Laid-Open No. 03-226989 Japanese Patent Laid-Open No. 06-07952

  However, in general, ferrite has a limit value of magnetic flux density penetrating due to its constituent materials and the like (magnetic saturation), and may become a bottleneck in improving the heating efficiency of the pan. In particular, when a central coil arranged in the central part and a plurality of peripheral coils arranged in the peripheral part are connected by a radially extending ferrite, the ferrite including the coil arranged in the central part is caused by other peripheral coils. Because the magnetic flux concentrates, even if a large number of coils are provided, the central ferrite is magnetically saturated, the magnetic flux density of the ferrite in the central coil cannot be increased, and consequently the heating efficiency of the pan cannot be increased. There was a problem.

  Therefore, the induction heating cooker according to the present invention includes a plurality of connection coils arranged in a grid, a plurality of base portions arranged in a grid below each of the connection coils, and each of the connection coils. A plurality of core parts extending from the base part through the center, a link part extending in at least one of the vertical direction and the horizontal direction and connecting the base parts adjacent to each other, and a high frequency current supplied to each of the connecting coils And the base part, the core part, and the link part are made of a high magnetic permeability material.

  According to the present invention, by connecting a plurality of heating coils arranged in a lattice shape with a ferrite member extending in the vertical direction and the horizontal direction, the object to be heated is efficiently heated without magnetic saturation of the ferrite member. be able to.

It is a perspective view which shows roughly the whole induction heating cooking appliance by Embodiment 1 which concerns on this invention. It is the top view which looked at the induction heating cooking appliance shown in FIG. 1 when the top plate was removed from upper direction. It is the top view which looked at the induction heating part when a heating coil was removed from the upper direction. It is sectional drawing when it sees from the IV-IV line of FIG. It is sectional drawing when it sees from the VV line | wire of FIG. It is a top view similar to FIG. 2 of the induction heating part containing the radially extending ferrite member which concerns on the prior art as a comparative example. It is a top view similar to FIG. 2 of the induction heating cooking appliance by the modification of Embodiment 1. FIG. It is sectional drawing similar to FIG. 4 of the induction heating cooking appliance by another modification of Embodiment 1. FIG. It is sectional drawing similar to FIG. 4 of the induction heating cooking appliance by another modification of Embodiment 1. FIG. It is a top view similar to FIG. 2 of the induction heating cooking appliance by Embodiment 2 which concerns on this invention. It is the same top view as FIG. 3 which looked at the induction heating part when the heating coil was removed from upper direction. FIG. 12 is a plan view similar to FIG. 11 of an induction heating unit according to a modification of the second embodiment. It is a top view similar to FIG. 10 of the induction heating cooking appliance by another modification of Embodiment 2. FIG. It is sectional drawing when it sees from the XIV-XIV line | wire of FIG. It is a top view similar to FIG. 2 of the induction heating cooking appliance by Embodiment 3 which concerns on this invention. It is sectional drawing when it sees from the XV-XV line | wire of FIG. It is a top view similar to FIG. 2 of the induction heating cooking appliance by Embodiment 4 which concerns on this invention. It is a top view similar to FIG. 2 of the induction heating cooking appliance by Embodiment 5 which concerns on this invention. It is a top view similar to FIG. 2 of the induction heating cooking appliance by the modification of Embodiment 5. FIG. It is a top view similar to FIG. 2 of the induction heating cooking appliance by Embodiment 6 which concerns on this invention. It is a top view similar to FIG. 2 of the induction heating cooking appliance by the modification of Embodiment 6. FIG.

  Embodiments of an induction heating cooker according to the present invention will be described below with reference to the accompanying drawings. In the description of each embodiment, a term indicating a direction (for example, “upward” and “downward”) is used as appropriate for easy understanding. Does not limit the present invention.

Embodiment 1 FIG.
The first embodiment of the induction heating cooker according to the present invention will be described in detail below with reference to FIGS. As shown in FIG. 1, the induction heating cooker 1 of the present invention generally includes a housing 7, a top plate 8 formed of glass or the like disposed on the uppermost portion thereof, an induction heating unit 10, and a user. And an operation unit 9 for adjusting the heating capacity of the induction heating unit 10. FIG. 2 is a plan view of the induction heating unit 10 viewed from above when the top plate 8 is removed.

  As shown in FIG. 2, the induction heating unit 10 according to Embodiment 1 includes a plurality of heating coils 11 arranged in a lattice shape (3 rows × 3 columns) in the housing 7. FIG. 3 is a plan view of the induction heating unit 10 with the heating coil 11 removed as viewed from above. The induction heating unit 10 in FIG. 3 includes a base unit 12 similarly arranged in a lattice form below each heating coil 11, and penetrates the center of each heating coil 11 upward from the base unit 12 (front side of the drawing). 2) and a link portion 14 extending in the vertical direction and the horizontal direction in the lattice arrangement of FIG. 2 and connecting the base portions 12 of the heating coils 11 adjacent to each other. Since the heating coil 11 according to the first embodiment is magnetically coupled to the adjacent heating coil 11 via the link portion 14, it is hereinafter referred to as “connected coil”. Further, the base portion 12, the core portion 13, and the link portion 14 are made of a non-conductive ferromagnetic material (ferrite material) and may be connected after being formed as separate members, or may be formed as an integral one. These are collectively referred to below as “ferrite member 15”. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 2, and includes the heated body (pot) P on the top plate 8.

The induction heating cooker 1 according to the present invention includes a high-frequency power source (not shown) having an inverter circuit that supplies a high-frequency current independently to each connecting coil 11. An example of the high-frequency power source of the present invention supplies a high-frequency current to each connection coil 11 arranged in a grid in FIG. 2, and each of the connection coils 11 shown in the uppermost stage in FIG. The phase is spatially sequentially switched so as to be S pole-N pole-S pole in the middle stage of FIG. 2 and N pole-S pole-N pole in the bottom stage of FIG. Reverse). That is, the high-frequency power source of the present invention supplies high-frequency currents having opposite phases to the connecting coils 11 adjacent to each other, and supplies high-frequency currents having the same phase to the connecting coils 11 disposed on the diagonal lines. As a result, the pot current is concentrated, and the pot heat generation is proportional to the square of R × I ² and the current, so that the pot heat generation increases and the heating efficiency is improved. This is used in cooking modes where heating efficiency is important. At this time, the high-frequency magnetic field generated in the coupling coil 11 shown in FIG. 4 forms a closed magnetic path (shown by a broken line 16 in FIG. 4) in the ferrite member 15 and the pan bottom P, and is caused by the high magnetic permeability of the ferrite member 15. The surrounding magnetic flux is attracted, and the heat generation efficiency at the pan bottom P can be increased. 2 passes through the core portion 13 of the coupling coil 11 shown in the middle of FIG. 2 through the magnetic flux generated by the coupling coils 11 adjacent in the vertical and horizontal directions, and is five times as much as the magnetic flux generated by one set of the coupling coils. The magnetic flux concentrates.
Note that, depending on the cooking mode, a current may be applied to the coil without spatially sequentially switching the phases so as to be N pole-S pole-N pole.

  FIG. 5 is a cross-sectional view taken along line VV in FIG. As shown in FIG. 5, the connecting coil 11 disposed on the diagonal line is supplied with the high-frequency current having the same phase, and the ferrite member 15 is not provided between them, so that the magnetic flux is chained between the coils. They do not interact and do not strengthen each other.

  On the other hand, as suggested in the above-mentioned Patent Documents 1 and 2, the connecting coil 11 arranged in a lattice shape is used with the ferrite members 15 (link portions 14) arranged radially as shown in FIG. When connected, the core portion 13 of the connecting coil 11 arranged in the middle of FIG. 6 passes through the magnetic flux generated by the connecting coils 11 adjacent in the vertical direction, the horizontal direction, and the diagonal direction. About 10 times as much magnetic flux is concentrated as compared with the magnetic flux generated in the above.

  As described above, the ferrite member 15 has a limit in the magnetic flux density that can be penetrated due to its constituent materials and the like, and even if many coils are provided, the ferrite member is magnetically saturated (the magnetic flux density is a predetermined value). The heat generation efficiency of the object to be heated (pan) P cannot be improved. Therefore, when the connecting members 11 arranged in a lattice shape are magnetically coupled using the radially arranged ferrite members 15 as shown in FIG. 6, the magnetic flux is applied to a part of the core portion that is a common magnetic path. The core portion is magnetically saturated due to the concentration of the magnetic flux, thereby limiting the magnetic flux density in each coil, and the object to be heated P cannot be efficiently heated.

  However, according to the induction heating cooker 1 of the present invention, the connecting coil 11 arranged in a lattice shape is connected using the ferrite member 15 (link portion 14) extending in the vertical direction and the horizontal direction. The to-be-heated body P can be efficiently heated without magnetically saturating the core 13 thus formed.

  In addition, although the connection coil 11 of the induction heating cooking appliance 1 which concerns on Embodiment 1 is connected by the link part 14 extended in a horizontal direction and a vertical direction, the link part extended only in any one of a horizontal direction and a vertical direction. 14 may be connected. That is, the connecting coil 11 shown in FIG. 7 is connected only by the link part 14 extended in a horizontal direction. As a result, the magnetic flux of the ferrite member 15 is concentrated in each link portion 14 of the coupling coil 11 arranged in the center of the first to third rows, as compared with the magnetic flux generated by one set of coupling coils. Saturation can be prevented.

Further, as shown in FIG. 8, the link portion 14 of two link elements (first and second link elements 14a, 14b) of the coupling coil 11 is divided into, by providing a predetermined small distance d ₁ between them, There is an advantage that it is easier to manufacture. Note that the minute distance d ₁ provided between the first and second link elements 14 a and 14 b is preferably smaller than the distance d ₂ from the core portion 13 to the heated body P.

  Furthermore, in the induction heating cooker 1 according to the first embodiment, the object to be heated P may be heated by using the ferrite member 15 without the core portion 13 (not shown). In this case, since there is no core part 13, compared with the case where the magnetic flux which a coil generate | occur | produces and the core 13 exists, the emitted-heat amount falls with the same coil current, and efficiency falls. However, there is an advantage that it can be configured at low cost.

  Moreover, in the induction heating cooking appliance 1 which concerns on Embodiment 1, as shown in FIG. 9, at least 1 edge part 17 extended upwards (parallel to the core part 13) from the base part 12 of the connection coil 11 arrange | positioned around. May be provided. At this time, the high-frequency magnetic field generated in the left and right connecting coils 11 shown in FIG. 9 is similarly closed in the base part 12, the edge part 17, the pot bottom P, and the core part 13 adjacent to the edge part (broken line in FIG. 9). 18) and can be reduced from the magnetic flux (magnetic flux 16 shown in FIG. 4) passing through the core portion 13 disposed in the center. Thus, the core 13 of the coupling coil 11 disposed in the center is not magnetically saturated, and the amount of heat generated in the pan is not reduced even in the same coil current as compared with the case where it is saturated. can do.

Embodiment 2. FIG.
Next, Embodiment 2 of the induction heating cooker according to the present invention will be described in detail below with reference to FIGS. The induction heating cooker 2 according to the second embodiment is roughly the induction heating cooker of the first embodiment except that the base portion 12 and the link portion 14 of the first embodiment are integrally configured as a base plate 21. 1 has the same configuration as that of FIG.

  FIG. 10 is a plan view of the induction heating unit 20 according to the second embodiment, and FIG. 11 is a plan view of the induction heating unit 20 with the connecting coil 11 removed as viewed from above. As described above, the induction heating unit 20 shown in FIG. 10 and FIG. 11 includes the connection coil 11 arranged in a lattice shape, the base plate 21 configured integrally with the base unit 12 and the link unit 14 of the first embodiment. And a plurality of core portions 13 extending upward from the base plate 21. The ferrite member according to the second embodiment is much easier to manufacture than the ferrite member prepared by separately connecting the base portion 12 and the link portion 14 of the first embodiment.

  According to the second embodiment, as in the first embodiment, anti-phase high-frequency currents are supplied to adjacent coupling coils 11, and in-phase high-frequency currents are supplied to diagonally connected coils 11. Supplied. Therefore, according to the induction heating unit 20 according to the second embodiment, similarly to the first embodiment, the opposite-phase magnetic fluxes generated in the coupling coils 11 adjacent in the vertical direction and the horizontal direction in FIG. In addition, the heating efficiency of the pot bottom P can be increased, and the heated object P can be efficiently heated without magnetically saturating the core portion 13 of the coupling coil 11 disposed in the center.

  Moreover, as shown in FIG. 12, in the base plate 21 of Embodiment 2, you may provide the opening part 22 between the connection coils 11 arrange | positioned on a diagonal line. In general, the coupling coil 11 generates heat due to its own Joule heat when energized, and must be maintained within a predetermined operating temperature range in order to perform proper control. Therefore, it is preferable to cool the connecting coil 11 by applying cooling air to the connecting coil 11 through the opening 22, and the opening 22 is very preferable for guiding the cooling air. Moreover, by providing the opening part 22 and reducing the area of the base plate 21, it can contribute to reduction of raw materials and weight reduction.

  Further, as shown in FIG. 13, a plurality of diagonal protrusions 23 made of a high magnetic permeability material may be provided between the coupling coils 11 disposed on the diagonal line. At this time, since the high-frequency current having the same phase is supplied to the coupling coil 11 disposed on the diagonal line, the magnetic flux generated in the diagonal protrusion 23 is oriented in the same direction as shown in FIG. It is possible to increase the heat generation efficiency at the pan bottom P.

  In induction heating cookers 1 and 2 according to the above-described embodiment, a sensor (not shown) that detects whether or not heated object P is arranged above each coupling coil 11 may be provided. At this time, the high-frequency power source does not necessarily supply the high-frequency current to all the connecting coils 11, and supplies the high-frequency current only to the connecting coil 11 in which it is detected that the body P to be heated is disposed above. Also good. As a result, since the high-frequency current is supplied only to the appropriate coupling coil 11 based on the position where the user places the pan P or the size of the pan P, wasteful power consumption can be avoided.

  Further, the connecting coil 11 according to the above-described embodiment has been described as being arranged in a 3 × 3 grid, but m rows × n columns (m, 2 × 2 and 4 × 4 columns, etc.) You may use the connection coil 11 arranged by n being a natural number of 2 or more.

Embodiment 3 FIG.
Next, the third embodiment of the induction heating cooker according to the present invention will be described in detail with reference to FIGS. 15 and 16. The induction heating unit 30 according to the third embodiment includes a plurality of heating coils 31 arranged in a lattice shape (3 rows × 3 columns) as shown in the figure, and a base unit 32 arranged below each heating coil 31. A core portion 33 that extends through the center of each heating coil 31 and extends upward from the base portion 32, and a peripheral portion 34 that extends upward (in parallel with the core portion 33) around each heating coil 31. Have However, unlike the induction heating unit 10, the induction heating unit 30 according to the third embodiment does not include a link unit that connects the base units 32 of the heating coils 31 adjacent to each other. That is, since the heating coils 31 according to the third embodiment are not connected to each other by the link portions and are independent, they are hereinafter referred to as “independent coils”. The ferrite member 35 according to the third embodiment includes a base portion 32, a core portion 33, and a peripheral edge portion 34. 16 is a cross-sectional view taken along line XV-XV in FIG.

  As in the first embodiment, the high-frequency power supply according to the third embodiment supplies high-frequency currents with opposite phases to the independent coils 31 adjacent to each other, and the high-frequency currents with the same phase supplied to the independent coils 31 arranged diagonally. Supply.

  In general, when a high-frequency current is supplied to one of the connecting coils 11 described in the first embodiment and not supplied to the other, the magnetic flux generated by one connecting coil 11 is linked to the other connecting coil 11, and the magnetic flux is A counter electromotive force to be countered is generated in the other coupling coil 11 and an induced current flows (magnetic coupling occurs). When coupling occurs, it becomes difficult for the high-frequency power source to supply an appropriate high-frequency current to the individual coupling coils 11, and wasteful power may be consumed. Therefore, it is preferable to suppress the coupling generated in the connecting coil 11 as much as possible.

  On the other hand, since the independent coil 31 according to the third embodiment is independent, magnetic coupling with the adjacent independent coil 31 hardly occurs (dashed line 36 in FIG. 16). Therefore, when it is desired to supply a high-frequency current only to an appropriate heating coil based on the arrangement position and dimensions of the object to be heated P, it is particularly effective to employ the independent coil 31 of the third embodiment. In addition, although you may abbreviate | omit about the core part 33 of the independent coil 31 shown in FIG. 16, the heat_generation | fever efficiency of the to-be-heated body P falls at this time.

Embodiment 4 FIG.
Next, the fourth embodiment of the induction heating cooker according to the present invention will be described in detail with reference to FIG. As described in the above embodiment, it is preferable to use the coupling coil 11 in order to increase the magnetic flux density of the closed magnetic path passing through the ferrite member 15 and the heated object P. Based on this, it is preferable to use the independent coil 31 when it is desired to control the individual heating coils independently. Therefore, Embodiment 4 intends to provide an induction heating cooker 4 that combines the coupling coil 11 and the independent coil 31 and takes advantage of the respective advantages.

  Specifically, as shown in FIG. 17, the induction heating unit 40 according to the fourth embodiment has a plurality (five) of connection coils 11 arranged in a cross shape and sandwiches the connection coils 11 around the connection coils 11. The connection coil 11 and the independent coil 31 are arranged in a lattice shape (3 rows × 3 columns). Below each connecting coil 11, a first base portion 12, a first core portion 13 extending through the center of each connecting coil 11 and extending upward from the first base portion 12, and a connecting coil adjacent to each other 11 link portions 14 for connecting the first base portions 12 in a cross shape. On the other hand, below each independent coil 31, a second base portion 32, a second core portion 33 extending through the center of each independent coil 31 and extending upward from the second base portion 32, and each independent coil A peripheral edge 34 extending upward from the second base portion 32 is disposed around the periphery 31. Although not shown, the induction heating unit 40 includes a high-frequency power source that supplies a high-frequency current independently to each of the coupling coil 11 and the independent coil 31. The first and second base parts 12, 32, the first and second core parts 13, 33, the link part 14, and the peripheral part 34 are formed using a high magnetic permeability material. The high-frequency power source supplies high-frequency currents having opposite phases to the adjacent connection coils 11 arranged in a cross shape, and the independent coil 31 has high-frequency currents having opposite phases to the connection coils 11 adjacent in the vertical and horizontal directions. Supply current.

  According to the induction heating cooker 4 of Embodiment 4, the magnetic flux density is increased and the efficiency is increased by supplying a high-frequency current to the connection coil 11 with respect to the heated object P disposed in the center of the induction heating unit 40. It can be heated well, and by supplying a high-frequency current to the independent coil 31 in addition to the connecting coil 11, the heated object P having a larger diameter can be efficiently heated with a stronger heating power (heating capacity).

Embodiment 5 FIG.
Next, Embodiment 5 of the induction heating cooker according to the present invention will be described in detail below with reference to FIGS. 18 and 19. As in the fourth embodiment, the fifth embodiment is intended to provide the induction heating cooker 5 that combines the coupling coil 11 and the independent coil 31 to make the best use of each advantage.

  As shown in FIG. 18, the induction heating unit 50 according to the fifth embodiment is generally disposed inside the link unit 14 and the four connection coils 11 in which the base unit is connected in a loop shape by the link unit 14. It has at least one inner independent coil 31a and a plurality of (four) outer independent coils 31b disposed outside the link portion 14, and the coupling coil 11, the inner independent coil 31a, and the outer independent coil 31b are latticed. Are arranged in a shape (3 rows × 3 columns).

  More specifically, below each connecting coil 11, a first base portion 12, and a first core portion 13 extending through the center of each connecting coil 11 and extending upward from the first base portion 12, A link portion 14 for connecting the first base portions 12 of the connecting coils 11 adjacent to each other in a loop shape is provided. On the other hand, below the inner independent coil 31a, the inner (second) base portion 32a and the inner (second) base portion extending through the center of the inner independent coil 31a and extending upward from the inner (second) base portion 32a. And an inner (first) peripheral edge 34a extending upward from the inner (second) base 32a around the inner independent coil 31a. Further, below the outer independent coil 31b, an outer (third) base portion 32b and an outer (third) extending through the center of the outer independent coil 31b and extending upward from the outer (third) base portion 32b. And an outer (second) peripheral edge 34b extending upward from the outer (third) base 32b around the outer independent coil 31b. Although not shown, the induction heating unit 50 includes a high-frequency power source that supplies a high-frequency current independently to each of the coupling coil 11, the inner independent coil 31a, and the outer independent coil 31b. (First to third) base parts 12, 32a, 32b, (first to third) core parts 13, 33a, 33b, link part 14, and inner and outer (first and second) The peripheral portions 34a and 34b are formed using a high magnetic permeability material. The high-frequency power supply supplies high-frequency currents having opposite phases to the adjacent coupling coils 11 connected in a loop.

  According to the fifth embodiment, the outer independent coil 31b may be omitted, the inner independent coil 31a may be omitted, and only the connecting coil 11 connected in a loop shape is provided, and adjacent to each other. You may provide the induction heating cooking appliance 5 which supplied the high frequency current of the antiphase to the connection coil 11. FIG. Moreover, in said Embodiment 5, although the induction heating cooking appliance 5 which connected the four connection coils 11 in the loop shape was demonstrated, as shown in FIG. 19, the six connection coils 11 were connected in the loop shape. It may be a thing. However, according to the fifth embodiment, since it is necessary to supply high-frequency currents having opposite phases to the coupling coils 11 adjacent to each other, the number of coupling coils 11 coupled in a loop shape must be an even number.

Embodiment 6 FIG.
Next, the sixth embodiment of the induction heating cooker according to the present invention will be described in detail with reference to FIGS. 20 and 21. FIG. The induction heating cooker 6 according to the sixth embodiment generally has the same configuration as the induction heating cooker 1 of the first embodiment except that the connecting coil 11 has a rectangular planar shape. Description of is omitted.

  As described above, each coupling coil 61 of the induction heating unit 60 shown in FIG. 20 has a rectangular planar shape. In general, when the heating coil forms a magnetic flux, the heated object P made of metal generates an induced current that cancels the magnetic flux and is heated by Joule heat generated thereby. Therefore, the drive current flowing in the heating coil and the induced current generated in the heated object flow in the reverse direction in principle. That is, the induced current generated in the heated object that is induced by the coupling coils arranged in a lattice form becomes an eddy current that flows in the opposite direction along the circumference of the coupling coil. When the connecting coil 11 having the circular planar shape of the first embodiment is used, the eddy current generated by the two adjacent connecting coils 11 is pinpointed at the position where the connecting coil is closest because the connecting coil is circular. As a result, the current in the pan is concentrated and increased. On the other hand, when the connecting coil 61 having the rectangular planar shape according to the sixth embodiment is used, the eddy current generated by the two adjacent connecting coils 61 is linear in the vertical direction or the horizontal direction in the substantial region 62. Current is concentrated over a longer distance than a circular coil. By increasing the strength of the eddy current flowing along a predetermined direction (longitudinal direction or lateral direction), surreal heat is generated in the heated body P by the square, and this distance is increased in the rectangular coil, so that the heat generation efficiency is increased. It becomes possible.

  Although the sixth embodiment has been described with reference to the first embodiment, the invention according to the sixth embodiment can be similarly applied not only to the connection coil 61 but also to the independent coil 31. It can be applied to any of the above first to fifth embodiments.

  Further, as shown in FIG. 21, according to the sixth embodiment, the rectangular coils 61a and 61b arranged in the periphery are designed to be larger than the rectangular coil 61c arranged in the center, and conform to the size of the heated object P. You may make it make it.

1 to 6: induction heating cooker, 10 to 60: induction heating unit, 7: housing, 8: top plate, 9: operation unit, 11, 31: coupling coil, 12, 32: base unit, 13, 33: core Portion, 14: link portion, 14a, 14b: first and second link elements, 15, 35: ferrite member, 17: edge portion, 21: base plate, 22: opening portion, 23: diagonal projection portion, 31 : Independent coil, 34: peripheral part, 61: rectangular coil, P: heated body (pan).

Claims (15)

A plurality of coupling coils arranged in a lattice pattern;
A plurality of base portions arranged in a lattice shape below each of the coupling coils;
A plurality of core portions extending from the base portion through the respective centers of the coupling coils;
A link portion extending in at least one of the vertical direction and the horizontal direction and connecting the base portions adjacent to each other;
A high-frequency power source for supplying a high-frequency current to each of the coupling coils,
The induction heating cooker, wherein the base part, the core part, and the link part are made of a high permeability material.   The induction heating cooker according to claim 1, wherein the link portion extends only in one of the vertical direction and the horizontal direction.   The induction heating cooker according to claim 1, further comprising at least one edge portion made of a high magnetic permeability material and extending in parallel with the core portion from the base portion of the coupling coil. The at least one link portion is divided into first and second link elements disposed a predetermined distance apart;
The induction heating cooker according to claim 1, wherein the predetermined distance is smaller than a distance from the core portion to the object to be heated.   The induction heating cooker according to claim 1, wherein the base portion and the link portion are integrally formed as a base plate.   The induction heating cooker according to claim 5, wherein the base plate has an opening between connecting coils disposed on a diagonal line.   The induction heating cooker according to claim 1, comprising a plurality of diagonal protrusions made of a high magnetic permeability material and extending in parallel with the core portion between the coupling coils disposed on the diagonal line.   The induction heating cooker according to claim 1, further comprising a plurality of sensors for detecting whether or not a heated object is disposed above each coupling coil.   Each induction coil has a rectangular planar shape, The induction heating cooking appliance of any one of Claims 1-8 characterized by the above-mentioned.   The induction heating cooker according to any one of claims 1 to 9, wherein a connecting coil arranged in the center in the vertical direction and the horizontal direction is larger than other connecting coils. A plurality of independent coils arranged in a lattice pattern;
A plurality of base portions disposed below each of the independent coils;
A plurality of core portions extending from the base portion through the respective centers of the independent coils;
A plurality of peripheral portions extending from the base portion in parallel with the core portion around each of the independent coils;
A high frequency power source for supplying a high frequency current to each of the independent coils,
The base portion, the core portion, and the peripheral portion are made of a high magnetic permeability material,
The induction heating cooker, wherein the high-frequency power source supplies a high-frequency current having an opposite phase to the independent coils adjacent to each other, and supplies the high-frequency current having the same phase to the independent coils arranged diagonally. A plurality of connecting coils arranged in a cross shape;
A plurality of first base portions arranged in a cross shape below each of the coupling coils;
A plurality of first core portions extending from the first base portion through the respective centers of the coupling coils;
A plurality of link portions connecting the first base portion in a cross shape;
A plurality of independent coils arranged in a lattice pattern;
A plurality of second base portions disposed below each of the independent coils;
A plurality of second core portions extending from the second base portion through the respective centers of the independent coils;
A plurality of peripheral portions extending from the second base portion in parallel with the second core portion around each of the independent coils;
A high frequency power source for supplying a high frequency current to each of the coupling coil and the independent coil;
The first and second base parts, the first and second core parts, the link part, and the peripheral part are made of a high permeability material,
The connecting coil is disposed between the independent coils;
The induction heating cooker, wherein the high-frequency power supply supplies a high-frequency current having an opposite phase to the connecting coils adjacent to each other. 4 or more even number of connecting coils;
A plurality of first base portions disposed below each of the coupling coils;
A plurality of first core portions extending from the base portion through the respective centers of the coupling coils;
A plurality of link portions connecting the first base portions adjacent to each other in a loop;
A high-frequency power source for supplying a high-frequency current to each of the coupling coils,
The first base portion, the first core portion, and the link portion are made of a high magnetic permeability material,
The induction heating cooker, wherein the high-frequency power supply supplies a high-frequency current having an opposite phase to the connecting coils adjacent to each other. At least one inner independent coil disposed inside the link part;
A plurality of second base portions disposed below each of the inner independent coils;
A plurality of second core portions extending from the second base portion through the respective centers of the inner independent coils;
A plurality of first peripheral portions extending from the second base portion in parallel with the second core portion around each of the inner independent coils;
The induction heating cooker according to claim 13, wherein the second base portion, the second core portion, and the first peripheral portion are made of a high magnetic permeability material. A plurality of outer independent coils disposed outside the link portion;
A plurality of third base portions disposed below each of the outer independent coils;
A plurality of third core portions extending from the third base portion through the respective centers of the outer independent coils;
A plurality of second peripheral portions extending from the third base portion in parallel with the third core portion around each of the outer independent coils;
The third base portion, the third core portion, and the second peripheral portion are made of a high magnetic permeability material,
The induction heating cooker according to claim 13 or 14, wherein the connecting coil, the inner independent coil, and the outer independent coil are arranged in a grid pattern.

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