JP2011243469A - Induction heating cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively cool a heating coil by blowing cooling air on a winding groove on a top face of the heating coil.SOLUTION: An induction heating cooker has: a heating coil which is provided below a top plate and is mounted on a coil base having a plurality of pieces of ferrite arranged radially therein; a substrate for controlling driving of the heating coil; a fan device for cooling the heating coil and the substrate; an antistatic plate provided in a space between the top plate and the heating coil; a space of vertical two layers provided in a space between the antistatic plate and the heating coil with a partition plate therebetween which has a plurality of openings; and a coil cooling air passage for ejecting the cooling air to the heating coil from the space above the partition plate toward the heating coil below the partition plate through the openings.

Description

  The present invention relates to an induction heating cooker, and more particularly to its air-cooled air passage structure.

  An induction heating cooker is a device that performs cooking by using Joule heating due to eddy current generated in a bottom of a pan when magnetic lines generated by flowing a high-frequency current through a heating coil pass through a metal cooking pan. During cooking, heat is generated not only from the cooking pot but also from the heating coil and the substrate that controls the heating coil. Specifically, a heating coil that performs induction heating generates heat due to eddy current loss or Joule loss due to high-frequency current supplied from the substrate, while a switching element that generates high-frequency current generates heat on the substrate.

  In order to cool these components, conventionally, air cooling using a fan device has been performed. A conventional cooling air path structure of an induction heating cooker uses a fan device such as an axial fan or a centrifugal fan to forcibly air-cool a plurality of substrates and heating coils.

  In recent years, induction heating cookers have been developed as one of the functional improvements due to the increased penetration rate. In addition to magnetic metal pans such as iron pans, products that can induction heat non-magnetic metal pans such as aluminum pans and copper pans have been developed. Has been.

  In such products, when the cooking pan to be induction-heated is a metal with low skin resistance, such as aluminum or copper, a higher frequency current is passed through the heating coil to increase the magnetic coupling between the cooking pan and the heating coil. It is heated. Here, in order to use the skin effect in a heating coil that allows high-frequency current to flow, a coil winding of a bundle of several hundred to several thousand strands of insulation-coated strands of 0.1 mm or less is used. In such a heating coil, when a coil voltage to be supplied is high, a leakage current is likely to be generated in the cooking pan. Therefore, a conductor (antistatic plate) is interposed between the top plate and the heating coil and grounded. Taken.

  Also, in induction heating of non-magnetic metal pans with low magnetic permeability such as aluminum pans and copper pans, it is difficult to generate heat due to eddy current generated at the bottom of the pan, and the heating efficiency of cooking pans is lower than magnetic metal pans such as iron, Heat generation due to eddy current loss and Joule loss of the heating coil increases.

  Since the eddy current loss of the heating coil is caused by the magnetic lines of force on the cooking pan on the top plate, the heat generation density is higher on the upper surface side of the heating coil, which is the top rate side, and becomes larger as the induction heating of the nonmagnetic metal pan. Therefore, when heating an aluminum pan or a copper pan, it is important to cool the upper surface of the heating coil more than the lower surface of the heating coil.

  In order to facilitate the cooling of the upper surface of the heating coil, a gap of about 2 mm to 8 mm is provided between the antistatic plate and the heating coil disposed above the heating coil for induction heating the non-magnetic metal pan, so that the cooling air can flow. Some have air paths.

  For example, in Patent Document 1, as a cooling air path structure of a heating coil, a ventilation hole is provided in the center of the heating coil, and a gap is further provided between the heating coil and a flat plate (top plate) to cool from the fan. There is a disclosure of a configuration in which the wind is dispersed above and below the heating coil and the cooling air is diffused radially from the ventilation hole in the center of the coil.

  Japanese Patent Application Laid-Open No. H10-228561 discloses a configuration in which cooling air is supplied from the center or side of the heating coil to the gap between the heating coil and the top plate as a cooling air passage structure of the heating coil.

  In Patent Document 3, a radial cooling air flow is formed in the gap between the heating coil and the top plate, a flow path gap adjusting means is provided above the induction heating coil, and the air path gap is uneven or inclined. There is disclosure.

JP 2004-171926 A JP 2005-302735 A JP 2004-273224 A

  Since the winding of the heating coil used in the induction heating cooker capable of induction heating an aluminum pan or a copper pan is a bundle of strands of several hundred to several thousand strands, its outer diameter becomes thick. Therefore, when a heating coil that performs induction heating of a cooking pan by winding a winding with a large outer diameter for several tens of turns like a conventional heating coil, the coil surface has a space between the arc of the winding. A deep V-shaped coil winding groove is formed.

  If there are large irregularities on the surface of the heating coil, it is difficult to uniformly apply the cooling air to the irregularities, and it is particularly difficult to cool the coil winding groove that is the depression. In addition, even if the cooling air flows in parallel to the heating coil in the recesses such as the coil winding groove, it is difficult for the cooling air to hit. Therefore, even if the air volume is simply increased, it is difficult for the cooling effect to appear.

  In Patent Document 1, since only the ventilation hole formed in the center of the heating coil is an air passage that guides the cooling air to the gap between the heating coil and the top plate, the cooling air is parallel to the heating coil in the circumferential direction of the heating coil. Therefore, only the convex portion is cooled with respect to the irregularities on the coil surface, and the concave portion (coil winding groove) is hardly cooled. Further, the cooling air flowing on the upper surface side of the coil has a lower wind speed toward the outer peripheral side of the coil, a temperature difference is likely to occur at the inner and outer periphery of the coil, and is likely to be higher at the outer peripheral side of the coil.

  In other words, when a radial uniform cooling air flow from the center of the heating coil is formed in the gap between the heating coil and the top plate, a flow in the winding direction (circumferential direction) of the heating coil is difficult to occur. The cooling air is difficult to hit.

  Further, Patent Document 2 describes a structure for blowing cooling air to the heating coil. The cooling air flows into the gap between the heating coil and the top plate from the horizontal direction, and a cooling air passage at the center of the heating coil. However, as in Patent Document 1, it does not have any configuration for improving the cooling performance for the recesses on the surface of the heating coil.

  Moreover, even if patent document 3 is the flow-path clearance adjustment means provided in the space above a heating coil, the expansion / contraction of the clearance gap is made | formed in the radial direction of the heating coil, Since a flow in the coil winding direction (circumferential direction) hardly occurs and the cooling air cannot be guided to the narrow V-shaped coil winding groove, the coil surface with large irregularities cannot be efficiently cooled.

  The present invention has been made to solve at least one of the above problems.

  In order to solve the above-mentioned problem, in claim 1, a top plate on which a cooking pan is placed, a heating coil unit that is disposed below the top plate and induction-heats the cooking pan, and a high-frequency current is supplied to the heating coil unit. An induction heating cooker comprising: a board on which electronic components are supplied; and a fan device that supplies cooling air for cooling the heating coil unit and the board, wherein the heating coil unit includes a coil base, The fan device comprises: a heating coil disposed on an upper surface of the coil base; a partition plate disposed above the heating coil; and an antistatic plate disposed above the partition plate. The cooling air supplied between the antistatic plate and the partition plate passes through a plurality of openings provided in the partition plate and the partition plate and the heating coil. Is supplied to, it was to cool the upper surface of the heating coil.

  According to a fifth aspect of the present invention, there is provided a top plate for placing the cooking pan, a heating coil unit disposed below the top plate for induction heating the cooking pan, and an electronic component for supplying a high frequency current to the heating coil unit. An induction heating cooker comprising: the heating coil unit; and a fan device that supplies cooling air for cooling the substrate, the heating coil unit comprising: a coil base; A heating coil disposed on the upper surface and an antistatic plate disposed above the heating coil, and the cooling air supplied from the fan device between the top plate and the antistatic plate, Cooling the upper surface of the heating coil that is supplied between the antistatic plate and the heating coil through a plurality of openings provided in the antistatic plate. It was.

  According to the present invention, since the cooling air flowing along the coil winding groove of the heating coil can be supplied, the heating coil can be efficiently cooled even when the coil winding groove of the heating coil is deep.

The exploded perspective view of the induction heating cooking appliance of Example 1. FIG. FIG. 3 is a side sectional view of the induction heating cooker according to the first embodiment. FIG. 2 is a side cross-sectional view of the coil cooling unit in FIG. 1. The air flow above the heating coil of Example 1. FIG. The side sectional view which expanded the coil cooling part of Drawing 3. The disassembled perspective view of the coil cooling part of FIG. Side surface sectional drawing of the coil cooling part of Example 2. FIG. Side surface sectional drawing of the coil cooling part of Example 3. FIG. Side surface sectional drawing of the induction heating cooking appliance of Example 3. FIG. Side surface sectional drawing of the coil cooling part of Example 4. FIG. FIG. 11 is an enlarged side cross-sectional view of the coil cooling unit of FIG. 10. The disassembled perspective view of the coil cooling part of FIG. Side surface sectional drawing of the induction heating cooking appliance of Example 5. FIG. Side surface sectional drawing to which the coil cooling part of Example 6 was expanded. The example of a shape of the partition plate of FIG. Side surface sectional drawing of the coil cooling part of Example 7. FIG. FIG. 17 is an exploded perspective view of the coil cooling unit of FIG. 16.

  Hereinafter, an induction heating cooker according to an embodiment of the present invention is an IH cooking heater having electromagnetic induction heating means composed of a heating coil, an inverter circuit, etc., and particularly induction of nonmagnetic metal pans such as aluminum pans and copper pans. An explanation will be given by taking an example of an IH cooking heater that can be heated.

  1 to 6, the induction heating cooker according to the first embodiment will be described with reference to a built-in type IH cooking heater having two IH heating units and one radiant heating unit on the upper surface and a roaster on the front surface. explain. In addition, it is good also as a structure provided with a 3 ports IH heating part on the upper surface instead of the structure which provides 2 ports of IH heating parts and the 1-radiant heating part on the upper surface. Further, a stationary IH cooking heater may be used instead of the built-in type IH cooking heater.

  FIG. 1 is an exploded perspective view showing the internal structure of the built-in type IH cooking heater, and has three pan mounting portions 90 a, 90 b, and 90 c on a top plate 9. Cooking pans (iron pans, aluminum pans, etc.) that can be induction heated are placed on the pan mounting part 90a or 90b and cooked, and cooking pans (such as earthen pans) that cannot be induction heated are placed on the pan mounting part 90c. Cook with heat.

  On the top surface of the IH cooking heater main body, there are provided a top plate 9, an intake port 9a and an exhaust port 9b for allowing air inside and out of the main body to enter and exit, and an operation unit 61 for operating the heating power of IH heating and radiant heating. The intake port 9a communicates with the lower intake portion 5a, and the exhaust port 9b communicates with the lower exhaust duct 10. Below the operation unit 61, a display unit 65 that displays information such as IH heating and thermal power of the radiant heating is provided.

  Further, a heating coil unit 22 is provided below the pot placement units 90a and 90b, and an electric heater 29 is provided below the pot placement unit 90c. Since the structures of the left and right heating coil units 22 are the same, the following description will focus on the right heating coil unit 22.

  As shown in FIG. 1, the heating coil unit 22 is held by a plurality of coil holding portions 27. The coil holding part 27 is an elastic holding part using a spring or the like, and the heating coil unit 22 is pressed against the top plate 9 by the coil holding part 27. As a result, the distance between the cooking pan and the heating coil unit 22 is kept constant, and stable induction heating can be realized.

  A roaster 1 is provided on the front left side of the main body for grilling fish with a heater. Further, an operation panel 60 for operating the heating power of the roaster 1 is provided on the front right side of the main body. The operation panel 60 is provided with an operation button 60a and a power switch 60b. A substrate storage case 5 to be described later is provided behind the operation panel 60. The air distribution duct 7, the outlet 7a, the jet chamber 70, and the jet hole 70a will be described later.

  Here, the IH cooking heater of this embodiment can induction heat both a magnetic metal pan and a non-magnetic metal pan. When heating a magnetic metal pan such as an iron pan or a stainless steel pan, a high frequency current of about 20 kHz is applied to the heating coil. When heating a non-magnetic metal pan such as an aluminum pan or a copper pan, a high-frequency current of 60 kHz or more is passed through the heating coil 220.

  When a high-frequency current is passed through a copper wire, a phenomenon called “skin effect” occurs. This is a phenomenon in which the high-frequency current flows in a concentrated manner on the skin side rather than the entire cross section of the copper wire. The higher the frequency of the high-frequency current, the greater the influence of the skin effect. For this reason, the electric resistance when a high frequency current of 60 kHz for heating the nonmagnetic metal pan is passed is larger than the electric resistance when a high frequency current of 20 kHz for heating the magnetic metal pan is passed, and the current flowing through the heating coil As a result, when a high-frequency current of 60 kHz is passed, the input power to the heating coil becomes small.

  In order to solve this problem, in the IH cooking heater of the present embodiment, about 1200 thin copper wires (element wires) having a diameter of about 0.05 mm and having an insulating film are bundled to form an insulating film, which is further twisted. The heating coil 220 was formed by spirally winding a coil winding coated with an insulating film. In this way, by increasing the total surface area of the copper wire of the heating coil 220, the influence of the skin effect can be reduced, that is, the electrical resistance can be reduced, and the amount of current flowing through the heating coil 220 is increased, that is, An increase in input power of the heating coil 220 can be realized. In addition, the diameter, the number, etc. of the strands mentioned here are examples, and the application object of this invention is not necessarily limited to the above-mentioned numerical value.

  However, the coil winding formed in this way is as thick as about 2 to 5 mm in diameter, and the recesses formed between the coil windings become deep, which makes it difficult to cool the recesses. Below, the structure for efficiently cooling the recessed part of the heating coil 220 is demonstrated in detail.

  First, the configuration of the heating coil unit 22 will be described in detail using the perspective exploded view of FIG. Ferrites 24 are provided radially on the coil base 21 at the bottom. The ferrite 24 is substantially U-shaped and is installed so that the two convex portions are on top. On the upper surface of the coil base 21, the heating coil 220 described above is placed and fixed by adhesion. By disposing the ferrite 24 below the heating coil 220, the magnetic flux generated in the heating coil 220 can be prevented from leaking downward, and the magnetic flux can be efficiently directed upward.

  Above the heating coil 220, a partition plate 26 having a plurality of openings 26a is disposed. The partition plate 26 may be a thin insulating material, and for example, a mica plate is suitable. On the upper surface of the partition plate 26, an inner circumferential spacer 20a and an outer circumferential spacer 20b are provided. The inner circumferential spacer 20a is composed of a plurality of protrusions, and the outer circumferential spacer 20b is composed of an annular wall surface. The partition plate 26 is supported by the coil base 21 at the center, and a coil upper surface cooling lower air passage 2b described later is formed between the heating coil 220 and the partition plate 26.

  On the partition plate 26, an antistatic plate 25 made of a conductive material is placed. Since the outer peripheral side spacer 20b contacts (seal) the antistatic plate 25 in the entire periphery, the coil upper surface cooling upper air passage 2a surrounded by these and the outer peripheral side spacer 20b is interposed between the antistatic plate 25 and the partition plate 26. Is formed.

  A temperature sensor 23 elastically fixed to the coil base 21 is provided at the center of the heating coil unit 22. The temperature sensor 23 is for indirectly detecting the temperature of the cooking pan from the temperature of the top plate 9, and for example, a contact-type temperature sensor such as a thermistor is used. As shown in FIG. 6, the temperature sensor 23 is placed on the sensor base 23 b, is urged upward by the spring 23 c, and is pressed against the top plate 9.

  Next, the outline of the cooling air path structure of the IH cooking heater of Example 1 will be described with reference to FIG. FIG. 2 is a side cross-sectional view of the IH cooking heater at the center position of the right side pan mounting portion 90a of FIG.

  As shown in FIG. 2, a substrate storage case 5 is provided behind the operation panel 60. Substrates 51 are stacked in the substrate storage case 5, and each substrate 51 is electrically connected to an electronic component 52 and a high heating element 59 that supply a high-frequency current to the heating coil 220 and to the heating coil 220. A heat sink 55 and the like are mounted. A fan device 4 is provided behind the substrate storage case 5. The fan device 4 includes a centrifugal fan 3 such as a turbo fan, a casing 30 that houses the centrifugal fan 3, a fan motor 39 that drives the centrifugal fan 3, and a motor support base 35 that supports the fan motor 39. It arrange | positions so that it may have a rotating shaft of the fan motor 39 in the front-back horizontal direction. Here, the fan device 4 is provided behind the substrate storage case 5. However, when the air inlet 9 a is provided in front of the main body, the fan device 4 is provided in front of the substrate storage case 5. Also good.

  When the fan device 4 is driven, the air intake 50a supplied through the air intake 9a and the air intake portion 5a is supplied to the substrate storage case via the plurality of air outlets 37 provided in the motor support base 35 as indicated by arrows. 5 is supplied to cool the substrate 51, the electronic component 52, the high heat generating element 59, and the like. The air that has cooled the substrate 51 and the like passes through the vent 5b on the upper surface of the substrate storage case 5 and is discharged to the outside of the substrate storage case 5 as the exhaust 50b. On the other hand, a part of the air emitted from the fan device 4 is supplied to the air distribution duct 7 provided above the substrate storage case 5 without passing through the substrate storage case 5, that is, without increasing the temperature. Heading to the coil unit 22.

  Next, the cooling air passage structure for cooling the heating coil 220 will be described in more detail using FIG. 3 in which the vicinity of the heating coil unit 22 of FIG. 2 is enlarged.

  First, the cooling air path for cooling the lower surface of the heating coil 220 will be described. The exhaust 50b discharged from the vent 5b enters the jet chamber 70, and is jetted from the plurality of jet holes 70a provided on the upper surface of the jet chamber 70 toward the lower surface of the heating coil 220, thereby cooling the lower surface of the heating coil 220. Further, a part of the air supplied to the air distribution duct 7 is ejected from the plurality of jet holes 70 a provided on the upper surface of the air distribution duct 7 toward the lower surface of the heating coil 220 to cool the lower surface of the heating coil 220. Here, as the jet hole 70a has a smaller diameter, high-speed air can collide with the heating coil, and the heating coil 220 can be effectively cooled. Further, the temperature distribution on the lower surface of the heating coil can be adjusted by arbitrarily setting the arrangement of the jet holes 70a, that is, the cooling location of the heating coil 220.

  Next, a cooling air path for cooling the upper surface of the heating coil 220 will be described. As shown in FIG. 3, a coil upper surface cooling upper air passage 2 a is formed between the antistatic plate 25 and the partition plate 26, and a coil upper surface cooling lower air passage 2 b is formed between the partition plate 26 and the heating coil 220. . The cooling air guided to the center of the coil upper surface cooling upper air passage 2a through the air outlet 7a provided on the upper surface of the end portion of the air distribution duct 7 and the coil cooling air passage 2 flows radially toward the outer periphery, It is supplied to the coil upper surface cooling lower air passage 2b through the opening 26a to cool the upper surface of the heating coil 220. The air that has cooled the heating coil 220 flows around the coil base 21 and is exhausted to the outside through the exhaust port 9b.

  The flow of the cooling air in the coil upper surface cooling upper air passage 2a and the coil upper surface cooling lower air passage 2b shown in FIG. 3 will be described in detail with reference to FIGS.

  FIG. 5 is an enlarged view of a portion indicated by A in FIG. As shown in FIG. 5, a convex portion formed by the coil winding 22a and a coil winding groove 22b (substantially V-shaped concave portion) formed between the coil windings 22a exist on the upper surface of the heating coil 220. To do.

  The cooling air supplied to the coil upper surface cooling upper air passage 2a through the coil cooling air passage 2 flows outward through the coil upper surface cooling upper air passage 2a, and a part thereof passes through the opening 26a of the partition plate 26. The coil upper surface cooling lower air passage 2b is supplied so as to be sprayed on the upper surface of the heating coil 220. As shown in FIG. 6, since the opening 26a is a narrow opening, the cooling air passing therethrough is supplied to the coil upper surface cooling lower air passage 2b by increasing the wind speed.

  The high-speed cooling air supplied to the coil upper surface cooling lower air passage 2b flows toward the outside of the heating coil 220, and efficiently cools the convex portion on the upper surface of the heating coil 220 around the region directly under the opening 26a. .

  Further, a part of the cooling air blown to the upper surface of the heating coil 220 is divided into left and right when colliding with the downstream side of the convex portion on the upper surface of the heating coil 220, and flows in the circumferential direction along the concave portion of the heating coil 220, The concave portion on the upper surface of the heating coil 220 is mainly cooled.

  The flow of cooling air for cooling the coil winding groove 22b will be described in more detail with reference to FIG. FIG. 4 is a plan view of the partition plate 26 and the heating coil 220. As shown here, the plurality of openings 26 a provided in the partition plate 26 are disposed concentrically and radially on the projection surface directly above the heating coil 220. Here, an example in which the two openings 26a on the inner peripheral side and the outer peripheral side are arranged on one radiation line is shown, but they may be arranged in a staggered manner by shifting them. Further, the number of concentric circles and straight lines formed by the plurality of openings 26a is not limited to those shown here, and the temperature distribution of the heating coil 220 can be arbitrarily controlled by appropriately setting these.

  Thus, in the present embodiment, the cooling air that flows radially and the cooling air that flows in the circumferential direction can be supplied to the upper surface of the heating coil 220. For this reason, in addition to being able to cool efficiently the convex part of the upper surface of heating coil 220, the concave part can also be efficiently cooled.

  About the operation | movement of the IH cooking heater of Example 1 demonstrated above, the case where a cooking pan is mounted in the pan mounting part 90a is demonstrated to an example.

  For example, after placing the cooking pan containing water on the pan mounting portion 90a, the power switch 60b of the operation panel 60 is turned on, and the operation portion 61 is operated to start heating. The operation state is displayed on the display unit 65, and heating control according to the heating power adjustment amount is performed.

  At the same time as the current flows through the heating coil 220, the fan device 4 operates. When a high frequency current is supplied to the heating coil 220, the temperature of the heating coil 220, the high heating element 59, the electronic component 52, the substrate 51, etc. rises. 3 to 5, the lower surface of the heating coil 220 is cooled by the cooling air blown from the jet hole 70a, and the air distribution duct 7, the coil cooling air passage 2, the coil upper surface cooling upper air passage 2a, The upper surface of the heating coil 220 generating a large amount of heat is efficiently cooled by the cooling air supplied through the coil upper surface cooling lower air passage 2b. Thereby, the temperature of the heating coil 220 during cooking can be kept below a desired temperature.

  Here, the fan device 4 may control the air volume stepwise or steplessly in advance by the heating adjustment amount, or by ON / OFF control or intermittent operation while measuring the temperature of the heating coil 220 or the high heat generating component 59. You may make it the structure which adjusts air volume.

  As described above, according to the IH cooking heater of the first embodiment, the flow of the cooling air toward the outer periphery and the flow of the cooling air toward the circumferential direction can be created on the upper surface of the heating coil 220. In addition to realizing cooling of the convex portion on the upper surface of the heating coil 220, the cooling of the concave portion can be effectively performed by supplying cooling air directly to the concave portion. Further, by adjusting the arrangement and number of the openings 26a on the partition plate 26, it becomes easy to concentrate cooling air and supply the cooling air to the portion where the heating coil 220 generates a large amount of heat.

  Example 2 will be described with reference to FIG. Note that the description of the configuration equivalent to that of the first embodiment is omitted.

  FIG. 7 is a side cross-sectional view of the vicinity of the heating coil unit 22 of the second embodiment. In addition to the cooling air ascending air path provided around the temperature sensor 23 shown in FIG. It is characterized in that a cooling air ascending air passage is also provided on the outer peripheral side of the inner peripheral convex portion.

  That is, in this embodiment, the inner diameter of the heating coil 220 is larger than the inner diameter of the U-shaped ferrite 24 opened upward, and the inner protrusion of the ferrite 24 and the heating coil 220 are arranged so as to leave a gap. The inner diameter of the heating coil 220 including the inner protrusions of the ferrite 24 is entirely the coil cooling air passage 2.

  With this configuration, it is possible to further reduce the airflow resistance of the air flowing into the coil upper surface cooling upper air passage 2a, and it is possible to expect an effect of increasing the operating air volume of the fan device 4 or reducing the fan noise by lowering the airflow resistance.

  Therefore, it becomes easy for air to flow into the coil upper surface cooling upper air passage 2a, and the cooling air can be efficiently supplied to the opening 26a of the partition plate 26 to lower the coil temperature.

  A third embodiment will be described with reference to FIGS. Note that the description of the configuration equivalent to that of the first embodiment is omitted.

  FIG. 8 is a side sectional view of the vicinity of the heating coil unit 22 of the third embodiment. Instead of the heating coil 220 shown in FIG. A heating coil was used.

  As shown in FIG. 8, in Example 3, the partition plate 26 does not exist above the inner coil 221, and the partition plate 26 exists only above the outer coil 222. That is, the coil upper surface cooling upper air passage 2 a and the coil upper surface cooling lower air passage 2 b partitioned by the partition plate 26 exist only above the outer coil 222. In addition, an air passage communicating the lower surface and the upper surface of the heating coil was provided outside the inner coil 221.

  While omitting the partition plate above the inner coil 221 and providing an air passage that communicates the lower surface and the upper surface of the heating coil outside the inner coil 221, the ventilation resistance in the vicinity of the inner coil 221 can be suppressed.

  Further, on the upper surface of the outer coil 222, the flow of the cooling air in the circumferential direction along the coil winding groove 22b described in FIG. 4 is formed by the high-speed cooling air that has passed through the opening 26a. Can be cooled.

  This is because the Joule heat generation of the outer coil 222 having a long wire length is larger than the Joule heat generation of the inner coil 221 having a short wire length, and thus a configuration for improving the cooling performance of the outer coil 222 is necessary. is there. In addition, since the flow rate of the cooling air supplied from the center of the heating coil becomes lower as it goes toward the outer periphery and cooling is likely to be difficult, it is desirable to arrange a configuration that increases the flow rate of the cooling air near the outer coil 222. is there.

  By adopting such a configuration, it is possible to improve the cooling performance of the outer coil 222 that is difficult to cool, and to provide a cooling air passage structure that further suppresses ventilation resistance.

  FIG. 9 is an outline of the cooling air passage structure of the IH cooking heater of the third embodiment, and the shape of the air passage on the upper surface of the substrate storage case 5 shown in FIG. The high heat generating element 59 mounted on 51 is moved to the middle substrate. That is, the cooling air that has exited the fan device 4 and has cooled the uppermost substrate 51 (the relatively low-temperature cooling air that has not cooled the high heating element 59), and the lowermost and middle substrate 51 that have exited the fan device 4. Both of the cooling air that has been cooled (relatively high-temperature cooling air that has cooled the high heating element 59) are supplied to the air distribution duct 7. The cooling air supplied through the air outlet 7a of the air distribution duct 7 is blown to the lower surface of the heating coil, cools the heating coil from the lower surface, and is supplied to the upper surface of the heating coil through the coil cooling air passage 2. The heating coil is cooled from the upper surface.

  In the IH cooking heater shown in FIG. 9, the cooling air passage structure can be simplified as compared with the first embodiment.

  Here, a double heating coil will be described as an example, but for example, a triple heating coil may be used.

  A fourth embodiment will be described with reference to FIGS. Note that the description of the configuration equivalent to that of the first embodiment is omitted.

  FIG. 10 is a side sectional view of the vicinity of the heating coil unit 22 of the fourth embodiment, in which the shape of the partition plate 26 shown in FIG. 3 of the first embodiment is modified. In other words, in this embodiment, the partition plate 26 is inclined so as to approach the antistatic plate 25 toward the outer periphery. Thus, the coil upper surface cooling upper air passage 2a becomes narrower toward the outer periphery, and the coil upper surface cooling lower air passage 2b becomes wider toward the outer periphery.

  FIG. 11 is an enlarged view of the main part of FIG. As shown here, by enlarging the entrance portion of the coil upper surface cooling upper air passage 2a, the ventilation resistance of the coil upper surface cooling upper air passage 2a can be suppressed, and the cooling air can be efficiently supplied to the opening 26a. Further, by inclining the opening 26a, the cooling air flowing through the coil upper surface cooling upper air passage 2a can be efficiently guided to the opening 26a and supplied to the coil upper surface cooling lower air passage 2b. Further, since the coil upper surface cooling lower air passage 2b becomes narrower toward the outer periphery, the speed of the cooling air supplied to the heating coil 220 from the outer opening 26a is supplied to the heating coil 220 from the inner opening 26a. The cooling air can be made faster than the speed of the cooling air, and cooling on the outer peripheral side of the heating coil 220 can be performed more efficiently.

  FIG. 12 is an exploded perspective view of the heating coil unit 22 of the fourth embodiment. Since the antistatic plate 25 and the partition plate 26 are closest to each other at the outermost peripheral portion, the antistatic plate 25 and the partition plate 26 may be tightly fixed at the outermost peripheral portion. By tightly fixing the outer peripheral side, the outer peripheral spacer 20b shown in FIG. 3 can be omitted, and the structure can be further simplified. In addition, the partition plate 26 may be manufactured by molding and may be inclined, or may be provided with slits radially and bent in a conical shape to be inclined.

  According to the fourth embodiment, it is possible to efficiently supply the coil cooling air to the opening of the partition plate by widening the gap at the entrance portion on the upper surface side of the heating coil and suppressing the ventilation resistance of the air passage flowing above the partition plate.

  Example 5 will be described with reference to FIG. Note that the description of the configuration equivalent to that of the first embodiment is omitted.

  FIG. 13 is a side sectional view of the vicinity of the heating coil unit 22 of the fifth embodiment. The shape of the partition plate 26 shown in FIG. 8 of the third embodiment is modified as shown in FIG. 11 of the fourth embodiment. Is. That is, the configuration in which the partition plate 26 does not exist above the inner coil 221 and the effect obtained thereby are as described in the third embodiment, and the configuration in which the partition plate 26 above the outer coil 222 is inclined. The effects obtained thereby are as described in the fourth embodiment.

  Embodiment 4 will be described with reference to FIGS. Note that the description of the configuration equivalent to that of the first embodiment is omitted.

  FIG. 14 is a side cross-sectional view of the main part of the heating coil unit 22 of the sixth embodiment, in which the shape of the sensor base 23b shown in FIG. 11 of the fourth embodiment is modified. That is, the radius of the sensor base 23b is increased and a downward push pin 23d is provided on the outer periphery of the sensor base 23b.

  FIG. 15 is a plan view of the partition plate 26 according to the sixth embodiment, in which the shape of the partition plate 26 shown in FIG. 4 according to the first embodiment is modified. That is, on the partition plate 26, radial openings 26a and slit grooves 26b opened on the inner peripheral side are alternately provided, and the inner peripheral side of the opening 26a is used as a push pin contact portion 26d. As shown in FIG. 14, the partition plate 26 shown here is arranged between the heating coil 220 and the antistatic plate 25, so that the partition plate 26 itself is not provided with a desired inclination in advance, on the inner peripheral side. The inner peripheral side of the flat partition plate 26 is pushed down by the provided push pin 23d, and a desired conical shape can be obtained. Therefore, the entrance side of the coil upper surface cooling upper air passage 2a can be easily regulated to a desired height. In the present embodiment, the configuration in which the push pin 23d is provided on the sensor base 23b is illustrated, but the configuration of the push pin is not limited to the above as long as the push pin contact portion 26d of the partition plate 26 can be pushed down. .

  According to the IH cooking heater of the sixth embodiment, in addition to the effects obtained by the configuration of the fourth embodiment, an additional effect that the manufacturing of the partition plate 26 becomes easy can be obtained.

  In addition, the partition plate 26 of FIG. 15 is provided with an opening 26a in addition to the slit groove 26b, and the arrangement and size can be appropriately adjusted according to the cooling state. The number and width of the slit grooves 26b are the same. Here, as the number of the slit grooves 26b is increased, the number of the push pins 23d is increased to block the air inlet of the coil upper surface cooling upper air passage 2a. From 8 shown in 15 to about ± 4 is a reasonable number. The slit groove 26b only needs to be easily bent and deformed, and the coil cooling performance can be adjusted by the arrangement and size of the opening 26a.

  Embodiment 7 will be described with reference to FIGS. Note that the description of the configuration equivalent to that of the first embodiment is omitted.

  FIG. 17 is a perspective exploded view of the heating coil unit 22 of the seventh embodiment. As shown here, an inner circumferential spacer 20a, an outer circumferential spacer 20b, and an opening 25a are provided on the antistatic plate 25. Yes. As apparent from FIG. 17, the heating coil unit 22 of the seventeenth embodiment is not provided with the partition plate 26 shown in the first embodiment and the like, and the coil upper surface cooling is performed between the top plate 9 and the antistatic plate 25. An upper air passage 2 a is provided, and a coil upper surface cooling lower air passage 2 b is provided between the heating coil 220 and the antistatic plate 25.

  FIG. 16 is a side sectional view of the vicinity of the heating coil unit 22 of the seventh embodiment. The cooling air supplied to the coil upper surface cooling upper air passage 2 a through the coil cooling air passage 2 is blown to the heating coil 220 through the opening 25 a of the antistatic plate 25.

  According to the IH cooking heater of the seventh embodiment, in addition to the effects obtained by the configuration of the first embodiment, the configuration of the heating coil unit 22 can be simplified.

  The antistatic plate 25 is for suppressing leakage current that is likely to occur in the cooking pan, and the total area of the openings 25a is preferably 10% or less. In the present embodiment, only the exhaust of the substrate storage case 5 is supplied to the air distribution duct 7, but a part or all of the cooling air supplied to the air distribution duct 7 is directly supplied from the fan device 4. It is also good.

  According to the seventh embodiment, by using the opening 25a of the antistatic plate 25, a flow toward the upper surface side of the heating coil can be configured at low cost without using a partition plate or the like. In addition, a partition plate is not required in the gap between the top plate and the heating coil, and the distance between the heating coil and the cooking pan is reduced accordingly, so that the heating efficiency can be improved.

DESCRIPTION OF SYMBOLS 1 Roaster 2 Coil cooling air path 2a Coil upper surface cooling upper air path 2b Coil upper surface cooling lower air path 3 Centrifugal fan 4 Fan apparatus 5 Board storage case 7 Air distribution duct 8 Ventilation duct 9 Top plate 9a Intake port 9b Exhaust port 10 Exhaust duct 20a Inner peripheral spacer 20b Outer peripheral spacer 21 Coil base 22 Heating coil unit 22a Winding wire 22b Coil groove 23 Temperature sensor 23b Sensor base 23d Push pin 24 Ferrite 25 Antistatic plate 26 Partition plate 26a Opening 26b Slit groove 27 Coil holding part 30 Casing 35 Motor support 37 Air outlet 39 Fan motor 51 Substrate 52 Electronic component 55 Heat sink 59 High heat generating element 60 Operation panel 70 Jet chamber 90 Pot mounting part 220 Heating coil 221 Inner coil 222 Outer coil

Claims (8)

A top plate on which the cooking pan is placed; a heating coil unit that is disposed below the top plate and that induction-heats the cooking pan; and a substrate on which electronic components that supply high-frequency current to the heating coil unit are mounted; An induction heating cooker comprising a heating coil unit and a fan device that supplies cooling air for cooling the substrate,
The heating coil unit is
A coil base, a heating coil disposed on the upper surface of the coil base, a partition plate disposed above the heating coil, and an antistatic plate disposed above the partition plate,
Cooling air supplied from the fan device between the antistatic plate and the partition plate is supplied between the partition plate and the heating coil through a plurality of openings provided in the partition plate, and the heating An induction heating cooker characterized by cooling an upper surface of a coil. The induction heating cooker according to claim 1,
The induction heating cooker characterized in that the plurality of openings provided in the partition plate are provided concentrically or radially. The induction heating cooker according to claim 1,
The heating coil unit can heat an aluminum cooking pot,
There are concave and convex portions formed by coil winding on the upper surface of the heating coil,
Through a plurality of openings provided in the partition plate, a part of the cooling air supplied between the partition plate and the heating coil flows in the circumferential direction along the recess formed by the coil winding. By this, the recessed part of the said heating coil is cooled, The induction heating cooking appliance characterized by the above-mentioned. The induction heating cooker according to claim 1,
An induction heating cooker characterized in that the partition plate is inclined so as to approach the antistatic plate toward the outer periphery. The induction heating cooker according to claim 1,
An annular outer peripheral spacer is provided on the outer periphery of the upper surface of the partition plate, and the outer peripheral side of the coil cooling upper air passage formed between the antistatic plate and the partition plate is sealed by the outer peripheral spacer. An induction heating cooker characterized by having A top plate on which the cooking pan is placed; a heating coil unit that is disposed below the top plate and that induction-heats the cooking pan; and a substrate on which electronic components that supply high-frequency current to the heating coil unit are mounted; An induction heating cooker comprising a heating coil unit and a fan device that supplies cooling air for cooling the substrate,
The heating coil unit is
A coil base, a heating coil disposed on the upper surface of the coil base, and an antistatic plate disposed above the heating coil.
Cooling air supplied from the fan device between the top plate and the antistatic plate is supplied between the antistatic plate and the heating coil through a plurality of openings provided in the antistatic plate. An induction heating cooker that cools an upper surface of the heating coil. A top plate on which the cooking pan is placed; a heating coil unit that is disposed below the top plate and that induction-heats the cooking pan; and a substrate on which electronic components that supply high-frequency current to the heating coil unit are mounted; An induction heating cooker comprising a heating coil unit and a fan device that supplies cooling air for cooling the substrate,
An induction heating cooker, wherein the cooling air is supplied to an upper surface of the heating coil through an opening provided directly above the heating coil of the heating coil unit. A top plate on which the cooking pan is placed; a heating coil unit that is disposed below the top plate and that induction-heats the cooking pan; and a substrate on which electronic components that supply high-frequency current to the heating coil unit are mounted; An induction heating cooker comprising a heating coil unit and a fan device that supplies cooling air for cooling the substrate,
An induction heating cooker characterized in that cooling air is supplied to the heating coil from directly above the heating coil of the heating coil unit to cool the recess on the upper surface of the heating coil.

Images