JP5653172B2 - Induction heating cooker - Google Patents

Description

  The present invention relates to an induction heating cooker, and more particularly to a structure of a heating cabinet provided with a heater heated by an induction current.

  Many electromagnetic induction cookers have a heating chamber for cooking grilled fish and the like. The heating chamber is generally called a grill, an oven, or a roaster, and heaters used for them include electrical resistance heaters such as a sheathed heater, a radiant heater, or a ceramic heater.

  In addition to the induction heating cooker, a microwave oven, an oven toaster, and the like are generally known as a heating cooker having a heating chamber using such an electric resistance heater. In these cooking devices, an electric resistance heater supplied with power from a power source through a power supply terminal generates heat by Joule heat generated by energization, thereby cooking the food disposed in the heating chamber. That is, the foodstuff in the heating chamber is heated by convection due to the high-temperature air in the heating chamber heated by the electric resistance heater, or by radiant heat from the high-temperature electric resistance heater.

  According to many conventional heating chambers, the electric resistance heater is fixed in the heating chamber and fixedly connected to the power supply terminal, and thus cannot be detached from the heating chamber. However, since the electric resistance heater has oil smoke generated from food in the heating chamber, a cooking device in which the electric resistance heater can be easily detached from the heating chamber has been desired so that it can be easily cleaned.

In the past, cooking devices have been proposed in which the heater is detachable from the heating cabinet to increase convenience.
For example, in the conventional microwave oven described in Patent Document 1, a coil that is a high-frequency magnetic field generating means is disposed on a top wall (ceiling) of a heating chamber via a heat insulating member, and high-frequency power is supplied from a power converter to the coil. By heating the top wall of the heating chamber, the food in the heating chamber is radiated and heated from above.

  The microwave oven disclosed in Patent Document 1 includes an induction coil provided on a side wall of a heating cabinet, and a guided coil that is embedded in a leg portion of an oven tray that is configured to be removable with respect to the heating cabinet and that faces the induction coil. By supplying a high frequency current to the induction coil, a high frequency current is induced to the induced coil in a contactless manner, and a heater electrically connected to the induced coil is heated to place it on the oven pan and on it. The placed food can be heated. The heater of Patent Document 1 is a ribbon-like or linear heating element embedded in an oven dish.

  In addition, the induction coil and the induced coil of Patent Document 1 are each configured by winding a lead wire on both leg portions of a U-shaped ferrite core and configured so that both leg portions of each ferrite core face each other. It is possible to efficiently heat the oven pan (and thus the food placed thereon) with high reliability and safety (without passing through electrical contacts) and without generating leakage magnetic flux.

Further, another conventional microwave oven described in Patent Document 2 is provided with a heating coil for induction heating the outer peripheral portion of an oven dish configured to be removable from two left and right locations. The oven dish has a magnetic material such as an iron plate with a hollow film formed on at least a heated portion thereof. The heating coil includes a coil wound like a bobbin used in a sewing machine and a core that efficiently supplies the magnetic flux generated by the coil to the oven dish. The core is U-shaped, for example, and the magnetic flux forms a closed magnetic path by the outer peripheral portion of the core and the oven pan so that the high-frequency magnetic flux does not leak to other portions. The oven dish has a lower surface made of a magnetic material such as magnetic stainless steel, and an upper surface made of a highly thermally conductive material such as aluminum or copper. The magnetic material is induction-heated by the magnetic flux generated in the coil and the core, and this generated heat is transmitted to the entire oven pan made of a highly thermally conductive material.

  An IH cooking heater generally forms an alternating magnetic field around it by supplying a high frequency current to a disk-shaped induction heating coil disposed below the top plate (the alternating magnetic field is placed on the top plate). The chain is linked to the pan), and an eddy current is formed in the pan to heat the pan itself. At this time, a leakage magnetic flux that does not contribute to the heating of the pan among the alternating magnetic field formed around the induction heating coil is generated, which may cause radiation noise or malfunction of the control circuit of the peripheral device.

  Therefore, the IH cooking heaters described in Patent Document 3 and Patent Document 4 have an annular electromagnetic shield member made of aluminum, copper, or the like disposed around the outer edge in the radial direction of the induction heating coil, so that the leakage magnetic flux is effective. To try to suppress.

  In addition, the IH cooking heater described in Patent Document 5 arranges a partition plate made of a nonmagnetic conductive material such as aluminum below the heating coil, thereby generating an eddy current in the partition plate, and the magnetic flux is below the partition plate. It is configured not to leak.

JP-A-6-42761 Japanese Patent Laid-Open No. 6-18044 JP-A-57-115795 Japanese Patent No. 4148212 JP 2009-283393 A

The problems of the cooking device described in the above patent document will be described below.
In the microwave oven described in Patent Document 1, an induction coil wound around a U-shaped ferrite core and a ribbon-shaped or linear heating element electrically connected thereto are made of a high thermal conductive ceramic. Therefore, the manufacturing process is complicated, and the legs of the oven dish in which the induced coil is embedded are enlarged. Patent Document 1 describes that the coil is miniaturized by driving with a high-frequency magnetic field, and that an air-core coil that does not require a core is used, but enlargement of the legs of the oven dish is avoided. In addition, the complexity of the manufacturing process is not solved. Furthermore, the oven dish is heated at the time of cooking. In particular, since the covering member for the conductive wire forming the induced coil is required to have high heat resistance, the cost of manufacturing the induced coil is increased, and the conductive wire of the induced coil is increased. It is not easy to maintain the reliability of the electrical connection between the heater and the heating element.

  Moreover, although the microwave oven described in patent document 2 carries out induction heating of the outer peripheral part of the oven plate comprised with magnetic materials, such as iron, using the heating coil arrange | positioned at the side wall of a heating cabinet, The central part of the oven dish is not as hot as the outer peripheral part (the temperature varies greatly), and the food placed on the central part of the oven dish cannot be heated sufficiently. Also, if the thickness of the high thermal conductivity material is increased to transfer sufficient heat to the center of the oven pan, the oven pan will become thicker and heavier overall, so the effective volume in the heating chamber will be smaller and heavier. Is inconvenient.

  The IH cooking heaters described in Patent Literature 3 to Patent Literature 5 use an electromagnetic shielding member made of aluminum, copper, or the like to suppress leakage magnetic flux, but have high cleaning properties that allow the heater to be freely detached from the heating chamber. There is no suggestion of a heating chamber such as a grill or oven.

  The present invention has been made to solve the above-described problems, and provides a heating cooker having a heater with a simple structure, and in particular, the leakage magnetic flux of the induction heating coil for the heating cabinet has induction heating for the heating cabinet. An object of the present invention is to provide an induction cooking device having a simple cooling structure while reducing the influence on a power supply circuit board that supplies a high-frequency current to a coil.

Induction heating cooker according to the present invention includes a heating chamber for the article to be heated is accommodated, is provided inside the heating chamber, a heater made of electrically closed conductor outside the heating chamber, the heating chamber provided on one side, and the induction heating coil heating chamber for heating by flowing an induced current to the heater, the heating chamber coil base that holds the induction heating coil for heating housing, an induction heating coil for heating housing from the outside A magnetic body which is provided so as to cover and strengthens the magnetic flux generated from the induction heating coil for the heating chamber in the direction interlinking with the heater, and is arranged on one side of the heating chamber outside the heating chamber, for the heating chamber A power supply circuit board that supplies high-frequency current to the induction heating coil, and an induction heating coil and power supply circuit for the heating cabinet that are installed so as to blow air from the direction along the gap between the induction heating coil for heating cabinet and the power supply circuit board Board A single cooling fan for retirement, to partition in air passages of the cooling air cooling fan causes the power supply circuit board side and the heating chamber for induction heating coil side, the power supply circuit board and the heating chamber for induction heating coil And a magnetic shielding plate disposed therebetween.

  According to the induction heating cooker according to the present invention, a heating chamber induction heating coil that heats an induction current through a heater of the heating chamber, and a power supply circuit board that supplies a high frequency current to the heating chamber induction heating coil are heated. The magnetic field strength in the power supply circuit board by the induction heating coil for the heating cabinet is increased because it is arranged in the space on one side of the cabinet, the magnetic shield is provided between the two, and the single cooling fan for cooling both is provided. Thus, the influence of the leakage magnetic flux of the induction heating coil for the heating cabinet on the power supply circuit board can be reduced, and an induction heating cooker having a simple cooling structure can be obtained.

It is a disassembled perspective view of the induction heating cooking appliance which concerns on Embodiment 1 of this invention. It is sectional drawing from the front surface of the heating chamber periphery of the induction heating cooking appliance shown in FIG. It is a perspective view of the heating cabinet periphery of the induction heating cooking appliance shown in FIG. It is an expanded sectional view from the front around the side plate of the heating chamber of the induction heating cooker shown in FIG. It is sectional drawing from the upper surface around the heating chamber of the induction heating cooking appliance shown in FIG. It is a perspective view of a power supply board circuit case periphery of the induction heating cooker shown in FIG. It is sectional drawing from the upper surface of the heating chamber periphery of the induction heating cooking appliance which concerns on Embodiment 2 of this invention. It is sectional drawing of the power supply board circuit case periphery of the induction heating cooking appliance which concerns on Embodiment 3 of this invention. It is a perspective view of the periphery of the power supply circuit board case of the induction heating cooker shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is an exploded perspective view of induction heating cooker 100 according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view from the front of the vicinity of the heating chamber 6 of the induction heating cooker 100 shown in FIG. FIG. 3 is a perspective view of the vicinity of the heating chamber 6 of the induction heating cooker 100 shown in FIG. 4 is an enlarged cross-sectional view from the front surface around the side plate 12 of the heating chamber 6 of the induction heating cooker 100 shown in FIG. FIG. 5 is a cross-sectional view from the upper surface around the heating chamber 6 of the induction heating cooker 100 shown in FIG. The induction heating cooker 100 is demonstrated based on FIGS.

  The induction heating cooker 100 according to the present invention cooks the heated cooking container 2 placed on the top plate 3 on the upper surface of the main body case 1 by induction heating with the induction heating coil 4a or by heating with the radiant heater 4b. It is possible to do. Further, the induction heating cooker 100 has a grill function for directly cooking the article to be heated 50 by radiant heat of a heater provided in a heating chamber 6 described later, and the temperatures of the upper heater 10 and the lower heater 11 are set to predetermined temperatures. And the oven function of heating the air in the heating chamber 6 and cooking the object to be heated 50 with the heated air.

  The top plate 3 is arrange | positioned at the upper surface side of the main body case 1, is comprised with heat-resistant glass etc., and mounts the to-be-heated cooking containers 2, such as a pan. In the induction heating cooker 100, three pan mounting portions 1a are formed on the upper surface side of the top plate 3, and positions corresponding to the induction heating coil 4a and the radiant heater 4b provided in the main body case 1 are shown. It is a mark for placing the cooked cooking container 2.

In the main body case 1, as shown in FIG. 1, an induction heating coil 4a, a radiant heater 4b, a coil base 4c, a power circuit board case 5, a cooling fan 17 (see FIG. 5), a duct 19 (see FIG. 6) and A heating cabinet 6 is provided.
Further, on the right side of the front surface of the main body case 1, a front operation unit 20a for setting a main power switch (not shown) of the induction heating cooker 20, the induction heating coil 4a, the radiant heater 4b, the heating power of the heating chamber 6, and the like. Is provided. Further, on the front portion of the top plate 3, a top surface for performing operations such as selection of the heating port of the induction heating coil 4a, the radiant heater 4b, and the heating chamber 6, setting of thermal power, selection of a cooking menu, start of heating, and heating stop. An operation unit 20b is provided. Furthermore, a control unit (not shown) that controls the heating operation, the display of the heating state, and the like is provided in the main body case 1.

  In the induction heating coil 4, an eddy current is generated in the cooked cooking container 2 placed above the induction heating coil 4 by the magnetic lines generated by the current, and the cooked cooking container 2 itself generates heat.

  The coil base 4c mounts the induction heating coil 4a. The coil base 4c is provided with ferrite or the like for preventing the magnetic flux generated from the induction heating coil 4a from flowing downward and concentrating the magnetic flux on the cooking container 2 to be heated. The coil base 4 c is supported from below by a support member (not shown) and is pressed against the top plate 3.

  The power supply circuit board case 5 is made of, for example, a heat-resistant resin, and when receiving an instruction from the user via the operation unit 20, the induction heating coil 4 a and the induction heating coil 13 for the heating cabinet are changed based on the contents of the instruction. A power supply circuit board 16 to be driven is accommodated.

  The radiant heater 4b is supplied with AC power of a normal commercial frequency, and the radiant heat is generated by the radiant heater 4b itself, thereby heating the cooking container 2 to be heated.

  The cooling fan 17 blows air for cooling the power circuit board 16, the induction heating coil 4 a, the heating chamber induction heating coil 13 and the heating chamber coil base 14, which will be described later. The configuration of the cooling fan 17 is not particularly limited. For example, a sirocco fan (blower fan) that is one of centrifugal fans may be employed.

  The duct 19 is disposed on the lower side of the coil base 4c, and cools the power circuit board 16, the heating induction coil 13 and the heating coil base 14, and a part of the air from the cooling fan 17 on the upper surface. It is possible to guide toward the induction heating coil 4a side through the opening 19a provided in the head.

  The heating chamber 6 can be placed with an object to be heated 50 (for example, fish) when grilling or baking. The heating chamber 6 is provided below the main body case 1. Hereinafter, the heating chamber 6 will be described in detail.

  As shown in FIGS. 1 and 2, the heating chamber 6 includes a front surface portion 6a (see FIG. 5) that is opened and closed by a door 7 to which a handle 7a is attached, a back surface portion 6b, a bottom surface portion 6c, an upper surface portion 6d, and left and right It is comprised by the box shape of the side part. The side surface portion of the heating chamber 6 includes one side plate 12a on the right side and the other side plate 12b on the left side as viewed from the front of the heating chamber 6 (see FIG. 2). In addition, a tray 8, a grill 9, an upper heater 10 and a lower heater 11 are provided in the heating chamber 6. Further, an induction heating coil 13 for heating chamber, a coil base 14 for heating chamber, and a magnetic body 15 are provided outside the right side of one side plate 12a of the heating chamber 6.

  The front surface portion 6 a is attached to the front surface when the heating chamber 6 is viewed from the front, and constitutes a part of the heating chamber 6. Although the shape of the front surface part 6a is not specifically limited, For example, the rectangular board material with arbitrary thickness may be sufficient. A door 7 is attached to the front surface portion 6a. The door 7 is a member that covers the front surface of the heating chamber 6.

  The door 7 is provided with a handle 7a protruding forward. When the user grasps the handle 7a and moves the door 7 in the front-rear direction, a pair of left and right metal rails (not shown) connected to the door 7, a tray 8 and a grill 9 described later are interlocked with each other in the front-rear direction. To open and close the heating chamber 6. In addition, this metal rail should just be movable back and forth along the rail receiving part (not shown) formed in the both sides | surfaces in the heating chamber 6. FIG.

  The bottom surface portion 6 c is attached to the bottom surface when the heating chamber 6 is viewed from the front, and constitutes a part of the heating chamber 6. Although the shape of the bottom face part 6c is not specifically limited, For example, the rectangular board material with arbitrary thickness may be sufficient.

  As shown in FIGS. 2 and 4, one side plate 12 a is formed with an upper recess 121 a and a lower recess 121 b that are recessed from the right side to the outside when the heating chamber 6 is viewed from the front. It constitutes a part of the heating cabinet 6. As shown in FIG. 2, an upper heater 10 and a lower heater 11 (described later) are attached to the upper recess 121a and the lower recess 121b, respectively, substantially parallel to the surface on which the induction heating cooker 100 is placed. The side plate 12a is made of a non-magnetic ceramic material having heat resistance. The shape of the concave portion of the side plate 12a is not limited to a substantially rectangular parallelepiped shape as shown in FIGS. 2 to 4, but in the following description, it is assumed that it has a substantially rectangular parallelepiped shape.

  The saucer 8 has a substantially rectangular parallelepiped shape without an upper surface, and can store, for example, water or oil therein. Usually, the receiving tray 8 is detachably supported on the left and right ends on the metal rail. Therefore, the tray 8 can be detached from the metal rail alone.

  The grill net 9 is placed on the tray 8. As shown in FIGS. 1 and 2, the grill 9 is composed of a plurality of front and rear wires, and the cross section viewed from the side has a C shape with the right side (rear side) open. The grill 9 includes a grill upper surface (an upper surface having a letter C shape in section C) and a lower surface of the grill net (a lower surface having a letter C shape in section C), and a lower heater 11 to be described later is disposed therebetween. An object to be heated 50 can be placed on the upper surface of the grill. Further, the lower surface of the grill net comes into contact with the tray 8, whereby the grill net 9 is held on the tray 8.

  As shown in FIG. 5, the upper heater 10 is composed of an electrically closed, closed-loop conductor. Moreover, as shown in FIG. 2, when viewed from the front, the right side of the upper heater 10 is placed on the lower surface of the upper recess 121a, and the left side of the upper heater 10 projects from the other side plate 12b to the heating chamber 6 side. It is mounted on the formed mounting shelf (not shown) and provided on a surface substantially parallel to the bottom surface portion 6c (or the surface on which the induction heating cooker 100 is mounted). The upper recess 121a and the mounting shelf support the upper heater 10. Similarly to the upper heater 10, the lower heater 11 is also made of an electrically closed conductor. When viewed from the front, the right side of the lower heater 11 is placed on the lower surface of the lower recess 121b, and the left side of the lower heater 11 is a shelf (not shown) that protrudes from the other side plate 12b to the heating chamber 6 side. It is placed and provided on a surface substantially parallel to the bottom surface portion 6c (or the surface on which the induction heating cooker 100 is placed). Further, the lower recess 121 b and the mounting shelf support the lower heater 11. In addition, although the shape of the upper heater 10 and the lower heater 11 is not specifically limited, it is good in a shape which has a breadth in the surface substantially parallel to the bottom face part 6c. Further, the upper heater 10 and the lower heater 11 are preferably made of a metal having a large volume resistivity or resistivity.

  The induction heating coil 13 for a heating cabinet is a metal wire wound in an annular shape for inducing an induction current in the upper heater 10 and the lower heater 11. As shown in FIGS. 2 to 5, the induction heating coil 13 for the heating chamber is wound in the front-rear direction of the heating chamber 6 on the right side of the side plate 12 a of the heating chamber 6 and outside the upper recess 121 a and the lower recess 121 b. It is provided by being rotated (refer to induction heating coil 13 for a heating chamber indicated by a broken line in FIG. 3). The heating chamber induction heating coil 13 is held by a heating chamber coil base 14 to be described later.

  In addition, in induction heating cooking appliance 100, either surface of induction heating coil 13 for heating cabinets and coil base 14 for heating cabinets is in contact, and, thereby, induction heating coil 13 for heating cabinets is held And

  The coil base 14 for a heating chamber has a shape corresponding to the recesses (the upper recess 121a and the lower recess 121b) formed in the side plate 12a. As an example of such a shape, the shape of the coil base 14 for a heating chamber will be described below. As shown in FIGS. 2 and 4, the heating chamber coil base 14 is provided so as to cover the upper recess 121 a, the lower recess 121 b, and the heating chamber induction heating coil 13, and is parallel to the side surface of the induction heating cooker 100. The cross section of the rough surface is U-shaped. In addition, the coil base 15 for heating chambers is good to comprise from material (for example, PET) with high heat resistance.

  The magnetic body 15 includes a first magnetic body 15a and a second magnetic body 15b. The first magnetic body 15a and the second magnetic body 15b have the same shape, but are installed in different places. As shown in FIGS. 2 to 4, the first magnetic body 15 a and the second magnetic body 15 b are substantially U-shaped in cross section, and each has a shape so as to cover the heating chamber coil base 14. . However, the shape of the magnetic body 15 is not particularly limited as long as the magnetic flux generated from the induction heating coil 13 for the heating chamber is strengthened in the direction of interlinking with the upper heater 10 and the lower heater 11. In induction heating cooking appliance 100 concerning form 1, it explains as what has the above-mentioned shape.

The first magnetic body 15a and the second magnetic body 15b are provided so as to cover a substantially central portion in the front-rear direction outside the upper concave portion 121a and a substantially central portion in the front-rear direction outside the lower concave portion 121b.
In addition, the 1st magnetic body 15a and the 2nd magnetic body 15b are provided so that the upper heater 10 and the lower heater 11 provided in the inside of the heating chamber 6 may be covered to the dotted line C, as shown in FIG. Good. Here, the dotted line C is a position penetrating the inside of the conductor loop of the upper heater 10 and the lower heater 11. By doing so, the magnetic flux in the direction interlinking with the upper heater 10 and the lower heater 11 (indicated by closed curves A and B with arrows in FIG. 4) is strengthened.

  As shown in FIG. 6, the power circuit board case 5 includes a first opening 5 c on the duct 19 side and a second opening 5 d on the upper surface. The first opening 5 c communicates with the duct 17 and is an entrance for introducing a part of the cooling air of the cooling fan 17 into the power circuit board case 5. The second opening 5d is an outlet for blowing upward the air that has cooled the inside of the power circuit board case 5.

  In the power circuit board case 5, the heating chamber power circuit board 16 a on which the heating chamber power circuit 5 a for driving the heating chamber induction heating coil 13 is mounted, and the induction heating disposed below the top plate 3. A top power circuit board 16b on which a top power circuit 5b for driving the coil 4a is mounted is provided, and each power circuit generates a current having a predetermined frequency and a predetermined current value. Is possible. The heating chamber power supply circuit board 16a is connected to the heating chamber induction heating coil 13 via a supply line (not shown) so as to supply current from the supply line to the heating chamber induction heating coil 13. It has become. Similarly, the top power supply circuit board 16b is connected to the induction heating coil 4a via a supply line (not shown), and supplies current from the supply line to the induction heating coil 4a. These supply lines are constituted by stranded wires in order to suppress radiation of radio waves from the supply lines.

  As shown in FIG. 5, the cooling fan 17 is provided behind the power circuit board case 5 and the heating coil base 14. The cooling fan 17 is sucked from the intake port 1 c behind the right induction heating coil 4 a via the intake / exhaust cover 1 b behind the top plate 3. Cooling air from the cooling fan 17 is supplied from the outlet of the cooling fan 17 to the power circuit board case 5, the heating chamber induction heating coil 13, and the heating chamber coil base 14 via the duct 19.

  The cooling air supplied to the power circuit board case 5 cools the power circuit board 16 and then blows upward from the outlet (not shown) of the power circuit board case 5 to surround the induction heating coil 4a and the radiant heater 4b. Cool down. Then, after the surroundings of the induction heating coil 4a and the radiant heater 4b are cooled, they are exhausted from the exhaust port 1d behind the left induction heating coil 4a and exhausted to the outside of the main body case 1 through the intake / exhaust cover 1b.

The cooling air supplied to the heating chamber induction heating coil 13 and the heating chamber coil base 14 cools the heating chamber induction heating coil 13 and the heating chamber coil base 14. And it exhausts from the exhaust port (not shown) of the main body case 1 front surface.
In the first embodiment, the exhaust gas is exhausted from the exhaust port on the front surface of the main body case 1. You may comprise so that the circumference | surroundings of 4b may be cooled.

  A magnetic shielding plate 24 is disposed between the power circuit board case 5 in which the power circuit board 16 is accommodated, the heating chamber induction heating coil 13 and the heating chamber coil base 14. The material of the magnetic shield 24 is made of aluminum or copper. The magnetic flux generated by the induction heating coil 13 for the heating cabinet does not interlink with the upper heater 10 and the lower heater 11, and in particular, the magnetic shield plate 24 cancels this magnetic flux against the magnetic flux leaking to the power circuit board 16 side. An eddy current flows to reduce the magnetic flux from the magnetic shield plate 24 toward the power circuit board case 5 side.

Next, operation | movement is demonstrated taking operation by the heating chamber 6 as an example.
When the main power switch of the front operation unit 20a is turned on, electric power is supplied to the induction heating cooker 100. The door 7 is pulled forward by holding the handle 7 a and the object to be heated 50 such as fish is placed on the grill net 9, and then the door 7 is pushed in so that the object to be heated 50 is accommodated in the heating chamber 6. And the front operation part 20a or the top | upper surface operation part 20b selects the heating operation in the heating cabinet 6, and the command which starts a heating is output to a control part.

  When the heating operation of the heating chamber 6 is started, the heating chamber power supply circuit 5a supplies a predetermined high-frequency current to the heating chamber induction heating coil 13 via a supply line. The induction heating coil 13 for the heating cabinet supplied with the high frequency current generates a high frequency magnetic field by magnetomotive force, and the upper heater 10 has the first magnetic body 15a as a magnetic path and the vicinity of one end on the side plate 12a side. An alternating magnetic flux is generated which is linked through the inner side of the conductor loop of the upper heater 10 and returns through the first magnetic body 15a again from the vicinity of the other end.

  In the upper heater 10 that is linked to the alternating magnetic flux, an induced current is generated in a direction that cancels the alternating magnetic flux, and Joule heat is generated by the electric resistance of the upper heater 10. The object to be heated 50 is heated from above by the Joule heat of the upper heater 10 and cooked.

  On the other hand, similarly to the case of the upper heater 10, the lower heater 11 has the second magnetic body 15 b as a magnetic path and the inner side of the conductor loop of the lower heater 11 from the vicinity of one end on the side plate 12 a side. An alternating magnetic flux is generated which is linked through and returned through the second magnetic body 15b again from the vicinity of the other end. However, in the case of the lower heater 11, the direction of the interlinkage magnetic flux is opposite to that of the upper heater, and as shown in FIG. 3, when the direction of the magnetic flux interlinkage with the upper heater 10 at an instant is upward. The direction of the magnetic flux interlinking with the lower heater 11 is downward.

  An induced current is also generated in the lower heater 11 interlinking with the alternating magnetic flux, and Joule heat is generated by the electric resistance of the lower heater 11. The object to be heated 50 is heated from below by the Joule heat of the lower heater 11 and cooked. Thus, since the to-be-heated material 50 is heated from upper direction and the downward direction, it can cook efficiently.

  Also, the one side plate 12a of the heating chamber 6 is formed with a recess 121a in which a part of the one side plate 12a is recessed outward when the heating chamber 6 is viewed from the front, and the first magnetic body Since 15a is configured in a U-shaped cross section according to the shape of the recess 121a, the magnetic flux generated by the induction heating coil 13 for the heating chamber can be efficiently guided into the recess 121a.

  Furthermore, since the upper heater 10 is provided in the recess 121a so that a part thereof is covered with the magnetic body 15a when the heating chamber 6 is viewed from the front, the magnetic flux generated by the induction heating coil 13 for the heating chamber is generated. Interlinks with the upper heater 10 efficiently. As a result, an induced current can be efficiently passed through the upper heater 10, and heat can be efficiently generated by this current. The lower heater 11 has the same effect.

  Among the magnetic fluxes generated by the induction heating coil 13 for the heating chamber, there is a leakage magnetic flux leaking around the heating chamber 6 in addition to the magnetic flux contributing to the heat generation of each heater in linkage with the upper heater 10 and the lower heater 11. These leakage magnetic fluxes generate heat in a member made of metal such as iron, and may cause malfunction when linked with a power circuit board.

  Therefore, a magnetic shield plate 24 is provided between the induction heating coil 13 for the heating cabinet and the power circuit board 16. Therefore, the magnetic field intensity in the power supply circuit board 16 by the induction heating coil 13 for the heating cabinet is reduced, and the influence of the leakage magnetic flux of the induction heating coil 13 for the heating cabinet on the power supply circuit board 16 can be reduced.

  When the heating operation of the heating chamber 6 is started, the cooling fan 17 is also rotated at the same time. The induction heating coil 13 for a heating cabinet supplied with the high frequency current generates heat due to the electric resistance of the coil winding itself. Furthermore, when the first magnetic body 15a and the second magnetic body 15b have hysteresis, the time waveform of the magnetic flux in the magnetic body is distorted, and hysteresis loss occurs. As a result, the induction heating coil 13 for the heating cabinet generates heat.

  When the cooling fan 17 is driven to rotate, the cooling fan 17 is supplied from the outlet of the cooling fan 17 to the power circuit board case 5, the heating chamber induction heating coil 13, and the heating chamber coil base 14 via the duct 19. Since a part of the cooling air is guided from the first opening 19a on the upper surface of the duct 19 toward the induction heating coil 4a, the induction heating coil 4a and the like are efficiently used by the air before cooling the inside of the power circuit board case 5. Can be cooled.

  Cooling air is supplied to the power supply circuit board case 5 from the first opening 5c to cool the power supply circuit board 16, and then blown upward from the second opening 5d on the upper surface of the power supply circuit board case 5 to generate an induction heating coil. Cool around 4a and the radiant heater 4b. Then, the air is sucked from the exhaust port 1d behind the left induction heating coil 4a, and exhausted to the outside of the main body case 1 through the intake / exhaust cover 1b.

  In this way, the cooling fan 17 cools the heating chamber power circuit board 16a and the top power circuit board 16b in the power circuit board case 5, and heats the power circuit components mounted on these boards. Can be protected from.

  Further, since the heating circuit power supply circuit board 16a and the top power supply circuit board 16b are accommodated in the power supply circuit board case 5, the power supply circuit board case 5 functions as a cooling air duct and is mounted on the power supply circuit board and these. It is possible to efficiently cool the power supply circuit components.

  On the other hand, the cooling air supplied to the heating chamber induction heating coil 13 and the heating chamber coil base 14 cools the heating chamber induction heating coil 13 and the heating chamber coil base 14. And it exhausts from the exhaust port (not shown) of the main body case 1 front surface. Thus, the induction heating coil 13 for heating chambers and the adjacent heating chamber coil base 14 are cooled by the cooling air from the cooling fan 17 to protect the induction heating coil 13 for heating chambers and peripheral components from heat. Can do.

  Thus, the induction heating coil 13 for heating chambers and the adjacent heating chamber coil base 14 are cooled by the cooling air from the cooling fan 17 to protect the induction heating coil 13 for heating chambers and peripheral components from heat. Can do.

  As described above, according to the induction heating cooker of the first embodiment, the heating circuit power circuit board and the top power circuit board in the power circuit board case are cooled by the cooling air from the single cooling fan. At the same time, since the induction heating coil for the heating cabinet and the adjacent coil base for the heating cabinet are cooled, an induction heating cooker with a simple cooling structure can be obtained. In addition, an induction heating coil for a heating chamber that heats an induction current through the heater of the heating chamber and a power circuit board that supplies a high-frequency current to the induction heating coil for the heating chamber are arranged in a space on one side of the heating chamber. In addition, since the magnetic shielding plate is provided between the two, the influence of the leakage magnetic flux of the induction heating coil for the heating cabinet on the power supply circuit board can be reduced.

Embodiment 2. FIG.
FIG. 7 is a cross-sectional view from the upper surface around the heating chamber 6 of the induction heating cooker 100 according to the second embodiment. The difference from the first embodiment is that an air volume distribution adjusting unit 24 a is provided at the windward end of the magnetic shield plate 24 disposed in the air path of the cooling fan 17. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and differences from the first embodiment will be mainly described.

  Usually, electronic components such as semiconductor switching elements used in the power supply circuit 5 mounted on the power supply circuit board 16 are weaker at a higher temperature than the induction heating coil 13 for the heating cabinet, and therefore the amount of air flowing to the power supply circuit board 16 side is heated. It is necessary to increase the amount of air flowing toward the induction heating coil 13 side. When the cooling air in the duct 19 is flowing uniformly, the air volume is distributed to the first opening 5c on the windward side of the power circuit board case 5 at the outlet on the downstream side of the duct 19 and the induction for the heating chamber. It is almost determined by the area ratio with the opening on the heating coil 13 side. This method of adjusting the area ratio and allocating the air volume has a low degree of freedom in design and requires a high cost, such as a need to change the mold in mass production design.

  On the other hand, by changing the length L and the inclination θ of the air volume distribution adjusting unit 24a in the magnetic shield plate 24, the distribution of the air volume flowing to the induction heating coil 13 side for the heating chamber and the air volume flowing to the power circuit board 16 side is distributed. Can be adjusted. The method of changing the length L and the inclination θ of the air volume distribution adjustment unit has the advantage that the degree of freedom in design is large, the adjustment is easy, and the cost is small.

  As described above, in the induction heating cooker according to the second embodiment, the magnetic shield plate is arranged in the air passage of the cooling air generated by the cooling fan, and the air passage is partitioned by the magnetic shield plate, so that the induction heating coil for the heating chamber is used. The amount of air flowing to the side and the amount of air flowing to the power supply circuit board can be adjusted with a simple configuration.

Embodiment 3 FIG.
FIG. 8 is a cross-sectional view around the power supply circuit board case 5 of the induction heating cooker 100 according to the third embodiment. In the third embodiment, the same parts as those in the first and second embodiments are denoted by the same reference numerals, and differences from the first embodiment will be mainly described.

  In the first or second embodiment, with respect to the cooling air generated by the cooling fan 17, the air path flowing toward the induction heating coil 13 for the heating cabinet and the air path flowing toward the power supply circuit board case 5 are in a parallel relationship. It is composed. On the other hand, in the third embodiment, as shown in FIG. 8, the air path on the power circuit board case 5 side and the air path on the induction heating coil 13 side for the heating cabinet are configured in series. Furthermore, the power circuit board case 5 side is arranged on the leeward side, and the induction heating coil 13 side for the heating cabinet is arranged on the leeward side.

  As shown in FIG. 8, the power circuit board case 5 and the induction heating coil 13 side for the heating chamber are arranged in parallel, and a magnetic shield plate 24 is arranged between them. As shown in FIG. 9, the power supply circuit board case 5 is provided with a first opening 5c on the windward side as in the first and second embodiments. On the other hand, the 2nd opening 5d provided in the leeward side is provided in the side surface by the side of the induction heating coil 13 side for heating cabinets.

  The cooling air generated by the cooling fan 17 passes through the duct 19 and enters the power circuit board case 5 from the first opening 5c, as shown in FIG. 8D. Then, in the power circuit board case 5, the heating chamber power circuit board 16a on which the heating chamber power circuit 5a is mounted and the top power circuit board 16b on which the top power circuit 5b is mounted are cooled, 2 from the opening 5d. The cooling air blown out from the second opening 5 d cools the heating chamber induction heating coil 13 and the heating chamber coil base 14 along the outside of the side plate 12 of the heating chamber 6, and moves toward the rear of the main body case 1. The cooling air is exhausted from the exhaust port 1d to the outside of the main body case 1 via the intake / exhaust cover 1b.

  By configuring the air path on the power circuit board case 5 side and the air path on the induction heating coil 13 side in the heating chamber in series, the cooling air generated by the cooling fan 17 is supplied only to the power circuit board case 5 side. The cooling fan 17 can be reduced in size.

  Further, as described above, the electronic components such as the semiconductor switching elements used in the power supply circuit 5 mounted on the power supply circuit board 16 are weaker at a higher temperature than the induction heating coil 13 for the heating cabinet. First, the power circuit board 16 side is cooled. Then, the power supply circuit board 16 side is cooled, and the cooling air whose temperature has risen is caused to flow toward the induction heating coil 13 side for the heating cabinet to be cooled.

  As described above, according to the induction heating cooker of the third embodiment, the power supply circuit board is disposed on the upstream side of the cooling air generated by the cooling fan, and the heating chamber is provided on the downstream side of the cooling air that has cooled the power supply circuit board. Since the induction heating coil is arranged, the cooling fan can be reduced in size, and the power supply circuit board and the induction heating coil for the heating chamber can be efficiently cooled.

  DESCRIPTION OF SYMBOLS 1 Main body case, 1a Pan mounting part, 1b Intake / exhaust cover, 1c Inlet / exhaust, 1d Exhaust, 2 Heated cooking container, 3 Top plate, 4a Induction heating coil, 4b Radiant heater, 4c Coil base, 5 Power supply circuit board Case, 5a Power supply circuit for heating cabinet, 5b Power supply circuit for top surface, 5c First opening, 5d Second opening, 6 Heating cabinet, 6a Front portion, 6b Back portion, 6c Bottom portion, 6d Top portion, 7 Door 7a handle, 8 pan, 9 grill, 10 upper heater, 11 lower heater, 12a side plate, 12b side plate, 121a upper recess, 121b lower recess, 13 induction heating coil for heating chamber, 14 coil base for heating chamber, DESCRIPTION OF SYMBOLS 15 Magnetic body, 15a 1st magnetic body, 15b 2nd magnetic body, 16 power supply circuit board, 16a power supply circuit board for heating cabinets, 16b top surface electricity Source circuit board, 17 Cooling fan, 19 Duct, 19a Opening, 20a Front operation section, 20b Top operation section, 24 Magnetic shield, 24a Air volume distribution adjustment section, 50 Heated object, 100 Induction cooking device.

Claims (5)

A heating chamber in which an object to be heated is stored;
A heater made of an electrically closed conductor provided in the heating chamber;
Outside the heating chamber , provided on one side of the heating chamber, an induction heating coil for a heating chamber that heats the heater by flowing an induction current;
A coil base for a heating chamber for holding the induction heating coil for the heating chamber;
A magnetic body that is provided so as to cover the induction heating coil for the heating chamber from the outside, and that strengthens the magnetic flux generated from the induction heating coil for the heating chamber in a direction interlinking with the heater;
Outside the heating chamber , disposed on one side of the heating chamber, a power supply circuit board for supplying a high frequency current to the induction heating coil for the heating chamber,
A single cooling fan installed to blow air from a direction along a gap between the induction heating coil for heating cabinet and the power supply circuit board, and cooling the induction heating coil for heating cabinet and the power supply circuit board; ,
The air passage of the cooling air the cooling fan is generated so as to partition between the power supply circuit board side and the heating housing for induction heating coil side, is disposed between the power supply circuit board and the heating housing for the induction heating coil A magnetic shield,
Induction heating cooker with. 2. The induction heating cooker according to claim 1, wherein the magnetic shield plate is formed with an inclined portion constituting an air volume distribution adjusting portion at an upwind end portion of the air passage .   The power supply circuit board is disposed upstream of the cooling air generated by the cooling fan, and the induction heating coil for the heating chamber is disposed downstream of the cooling air that has cooled the power supply circuit board. The induction heating cooker according to 1. A board case for housing the power supply circuit board is provided, and a first opening and a second opening are provided on the upstream side and the downstream side of the board case with respect to the cooling air generated by the cooling fan, respectively. The induction heating cooker according to any one of claims 1 to 3.   The induction heating cooker according to claim 4, wherein the second opening is provided on a side surface on the induction heating coil side.

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