JP6887395B2 - Induction heating cooker - Google Patents

Description

The present invention relates to an induction heating cooker.

An induction heating cooker is a device that performs cooking by utilizing Joule heating by an eddy current generated at the bottom of a metal pot when a magnetic field line generated by passing a high frequency current through a heating coil passes through a metal pot. At the time of heating, heat is generated not only from the pan but also from the heating coil and the substrate that controls the heating coil, so that the fan device is used to perform blast cooling.

There are two types of induction heating cookers, a stationary type that is installed on the table of the system kitchen and a built-in type that is built into the kitchen. Both are grills equipped with a heat source such as an electric heater as well as induction heating of the cooking pot on the top plate. It has a structure for cooking such as grilling fish in the kitchen.

In these conventional induction heating cookers, the main parts to be cooled are a plurality of heating coils and a substrate. Structurally, the heating coils are stored near the top plate above the main body and the substrate is stored in the surplus space on the side of the grill. The configuration is common.

In recent years, induction heating cookers have changed the litz wire material of the heating coil from copper to aluminum from the viewpoint of expanding the volume of the grill, increasing the thermal power (power consumption), and reducing the cost from the viewpoint of improving convenience and comfort. There is a tendency for the mounting density and heat generation of built-in components to increase.

Since most system kitchens in Japan have specified dimensions, the maximum external dimensions are roughly fixed regardless of the type of induction heating cooker, and the heating coil and substrate can be cooled in a limited space. It is necessary to construct the optimum air passage.

In a conventional general induction heating cooker, the substrate is installed in a resin box shape or a flat plate (board stand) for insulation from the metal main body outer shell, and is arranged in multiple stages in the vertical direction of the main body. A fan device is provided in a part of the air passage that flows through the substrate, and cooling air is circulated on each substrate to cool the substrate and the overheating coil.

Also in Patent Document 1, "In the main body, the grill heating portion and the side of the grill heating portion are arranged, and the output control board and the cooling fan are housed inside, and the side surface and the upper portion are closed. A resin substrate case is installed, and the substrate case has a case intake port provided at an upper position corresponding to an intake port and a plurality of cooling ports provided at an upper position of the substrate case, and is inside the substrate case. An air passage is formed from the case intake port to a plurality of cooling ports, a cooling fan is arranged upstream of the air passage, and an output control board is arranged downstream, and the air sucked from the case intake port cools the output control board. After that, the air is discharged from a plurality of cooling ports, and the air discharged from the plurality of cooling ports cools the plurality of heating coils. ”The air circulating in the substrate case is applied to the outer shell of the substrate case. The structure is such that cooling air is blown from the arranged openings toward the heating coil.

JP-A-2007-149704

Conventional induction heating cookers such as Patent Document 1 have a storage structure with a high mounting density in which a plurality of substrates are divided on the side of the grill and arranged on top of each other in the vertical direction. Efficient cooling is an issue. For this reason, the substrate and the cooling fan (fan device) are housed in a narrow space inside the substrate case, and it is difficult to take a cooling air passage, which makes it complicated. The air passage for cooling the substrate and the heating coil becomes long, and the flow resistance of the cooling air increases, so that the load on the cooling fan increases and the motor power increases. In addition, the turbulence of the wind speed distribution and the increase in ventilation resistance caused by the complicated air passages deteriorate the ventilation performance of the cooling fan, which causes a decrease in the cooling performance of parts and an increase in fan noise (operating noise). .. Further, stagnation of the flow is likely to occur in the substrate case, hot air is retained, and the substrate is likely to fail.

In addition, since the gap between the grill storage and the board case becomes smaller, heat infiltration into the board side increases when the grill storage is used, which raises the temperature of parts on the board and deteriorates reliability such as shortening the life of parts. Become.

In order to solve the above problems, the induction heating cooker according to the present invention includes a main body, a top plate installed on the upper surface of the main body, two left and right heating coils provided below the top plate, and left and right heating coils. A grill storage provided below one of the heating coils, a substrate case for storing a substrate provided on either the left or right side of the grill storage, and an inverter for supplying high-frequency power to the heating coil housed in the substrate case. On the inverter board on which the circuit is mounted, the control board that supplies and controls power to the grill storage housed in the board case, the case lid that covers the board case from above and mounts the heating coil, and the board case. In an induction heating cooker equipped with a fan device for sucking cooling air, the inverter board and the control board are housed in two upper and lower stages in the board case, and the board case is in the gap between the grill and the inverter circuit. A duct that flows through the upper surface of the case lid from below is arranged.

The details will be described in the embodiment for carrying out the invention.

According to the present invention, it is possible to realize an air-cooled structure capable of suppressing a rise in substrate temperature when using a grill and retention of hot air in a substrate case and suppressing failure.

Perspective view of the induction heating cooker of Example 1 An exploded perspective view of the induction heating cooker shown in FIG. Schematic diagram of the side cross section cut along the AA line shown in FIG. Schematic diagram of the front cross section cut along the CC line shown in FIG. An exploded perspective view of the substrate case of Example 2 and the parts housed in the case lid. Side sectional view of the induction heating cooker of Example 2 Schematic diagram of the front cross section of the induction heating cooker of FIG. Top sectional view of the substrate case of FIG. Top sectional view of the case lid of FIG. Modification 1 of FIG. Modification example 2 of FIG. Top sectional view of the case lid of FIG. An exploded perspective view of the substrate case of Example 3 and the parts housed in the case lid. Schematic diagram of the side cross section of the induction heating cooker of Example 3

Examples of the present invention will be described in detail with reference to the drawings as appropriate. In addition, front and back, up and down, left and right are defined as shown in FIG. 1 and the like with reference to the line of sight of the user facing the induction heating cooker Z (see FIG. 1).

<Structure of induction heating cooker>
1 is a perspective view of the induction heating cooker Z of the first embodiment, FIG. 2 is an exploded perspective view of FIG. 1, FIG. 3 is a schematic view of a side cross section cut along the line AA shown in FIG. 1, and FIG. 4 is a schematic view. It is a schematic view of the front cross section cut by the CC line shown in FIG.

First, as an example, a case where the induction heating cooker Z (see FIG. 1) is a stationary type IH (Induction Heating) cooking heater provided with a grill storage 5 for heating an object to be cooked with an electric heater or the like will be described. In the present invention, an induction heating cooker having a grill storage 5 and having a substrate 7 arranged in two upper and lower stages on the side of the grill storage 5 and having an air passage formed by a fan device 9 installed upstream of the substrate 7. If so, it can be easily applied.

The induction heating cooker Z is a device in which an eddy current is generated at the bottom of a metal cooking pot (not shown), and Joule heat generated by the eddy current generates heat in the cooking pot itself. In FIG. 2, the eddy current is generated when a high-frequency current of, for example, about 20 kHz to 40 kHz is passed through the heating coils 3a and 3b, and the magnetic flux changes with time. The induction heating cooker Z mainly includes a main body 1, a top plate 2, heating coils 3a and 3b, a substrate case 8, a case lid 6, and a grill storage 5.

The main body 1 is a housing having an outer shell corresponding to the space (predetermined left-right width, front-rear width, height) in which the induction heating cooker Z is installed, and exhibits a box shape (concave shape) with an open upper part. There is. A grill storage 5 on the left side, a substrate case 8 and a case lid 6 on the right side, a heating coil 3 located above them, and the like are installed on the main body 1, and a top plate 2 is installed so as to cover the lid from above. ing.

The substrate case 8 has an inverter substrate 7a for supplying a high-frequency current to the heating coils 3a and 3b by an inverter circuit (not shown), and a control for heating and controlling the grill storage 5 with a relay (not shown) or the like. It houses the substrate 7b.

The inverter board 7a on which the high heat generating element 72 that generates a large amount of heat is mounted is provided with a heat sink 79 for diffusing and cooling the heat over a wide area. The heat sink 79 is a radiator that absorbs heat from the high heat generating element 72, which is an electronic component having high heat generation, and dissipates heat to the air flowing in through the fan device 9.

The heat sink 79 has a plurality of fins (not shown) extending substantially horizontally with the inverter substrate 7a, and the fins are directed toward the discharge port 95 so that air can flow. The heat sink 79 is installed on the upstream side near the fan device 9, and is arranged so that the high heat generating element 72 having a large heat generation amount is first cooled by the air flowing in through the discharge port 95. By arranging the heat sink 79 in the vicinity of the discharge port in this way, the high heat generating element 72 is efficiently cooled.

Here, the inverter circuit includes a plurality of switching elements (for example, IGBT: Insulated Gate Bipolar Transistor). Examples of the high heat generating element 72 include two switching elements used in a half bridge circuit and a diode bridge in a rectifier circuit. Further, the electronic components 71 on the substrates 7a and 7b are integrated circuits, inverter circuits, capacitors, etc. used for configuring an inverter circuit, supplying a high-frequency current to the heating coil 3, driving a fan device 9, and the like. It is a resistor or the like.

In the board case 8, the inverter board 7a on which a heavy object such as a heat sink 79 is installed is arranged in the lower stage, and the control board 7b having a smaller component heat generation amount than the inverter board 7a is arranged in the upper stage. That is, the case lid 6 is installed above the control board 7b housed in the board case 8, and most of the electronic components are housed in the board case 8 and the case lid 6 molded from an insulating material such as resin, and the fan. The main ventilation path of the device 9 is composed of a substrate case 8 and a case lid 6.

A fan device 9 is provided on the back side of the main body 1 of the inverter board 7a arranged in the board case 8, and outside air is sucked from the intake opening H1 provided on the rear right side of the top plate 2 and blown out toward the inverter board 7a. It is composed. That is, the fan device 9 is arranged on the most upstream side in the air passage from the intake opening H1 to the exhaust opening H2.

In the present invention, the duct 80 is molded in the case lid 6 to form an air passage penetrating the case lid 6 in the vertical direction. The duct 80 is provided between the heat sink 79 and the grill storage 5 that form the inverter circuit in the inverter board 7a, and forms an air passage that flows from the space between the control board 7b and the inverter board 7a to the upper surface of the case lid 6. Further, the duct 80 is configured to suppress heat intrusion of heat energy generated in the grill storage 5 into the substrate case 8 side. By forming the duct 80 into a rectangular shape such as a rectangle that is long in the front-rear direction of the main body, a large area for shielding the left and right can be obtained, and the cross-sectional area of the air passage can be widened to reduce the flow resistance.

The heating coil 3 is installed below the top plate 2, and a temperature sensor 34 that detects the temperature of the bottom of the pot is installed near the center of the heating coil 3. Further, the heating coil 3 is arranged on the downstream side away from the fan device 9, and after the cooling air passes through the substrate case 8, the heating coil 3a passes through the air guide duct D1 provided on the case lid 6. 3b is designed to be cooled. The air duct D1 faces the lower surfaces of the heating coils 3a and 3b, and the air blown from the fan device 9 is diverted toward the two heating coils 3a and 3b. As a result, the air from the fan device 9 can be directly blown from the lower side to the heating coils 3 provided on the left and right sides.

The heating coil 3 is a coil wound with a litz wire through which a high-frequency current flows by driving an inverter circuit (not shown) of the inverter board 7, and is mounted on a coil base 31. In this embodiment, heating coils 3a and 3b are provided one on each side in a plan view. The coil base 31 is supported by three support portions 32 (for example, springs), and the support portions 32 provide an upward urging force. As a result, the heating coil is pressed against the lower surface of the top plate 2, and the distance between the cooking pan and the heating coil 3 is kept constant.

As shown in FIG. 1, the grill storage 5 on the left side of the front surface of the main body 1 is provided with a door portion 5a on the front surface for installing a food to be cooked (not shown) by sliding back and forth. Further, the top plate 2 is composed of a plate-shaped glass (not shown) on which a pan to be cooked is placed and a frame portion (not shown) that holds the outer circumference of the plate-shaped glass so as to cover the main body 1 from above. It is installed in. The top plate 2 includes a two-port pot mounting portion 21 corresponding to the installation positions of the two heating coils 3a and 3b, an operation portion P0 for adjusting the heating and cooling of the pot to be cooked, and an intake opening H1. , Has an exhaust opening H2. An exhaust cover 25 having a plurality of holes is placed on the intake opening H1 (right side) and the exhaust opening H2 (left side) of the top plate 2, so that cooking utensils such as chopsticks and spoons and dust can be easily removed. It has a structure that does not infiltrate.

FIG. 3 is a schematic view of a side cross section cut along the line AA shown in FIG. 1, and mainly shows the positional relationship between the heating coil 3a on the right side, the inverter board 7a, and the fan device 9. Here, the fan device 9 shown in this embodiment is a multi-blade fan, and the rotation axis is in the left-right direction of the main body. Therefore, the intake port 9a is arranged so as to be in the side surface direction of the fan device, and the discharge port 95 is arranged so as to be in the front direction of the main body. An intake opening H1 for taking in air from the outside by driving the fan device 9 is provided on the rear surface side of the top plate 2. The discharge port 95 of the fan device 9 is located between the bottom surface of the substrate case 8 and the control substrate 7b, and the blown air (mainstream) flows toward the heat sink 79 between the inverter substrate 7a and the control substrate 7b. After that, the mainstream flows toward the inlet of the duct 80 provided in the case lid 6, and forms a flow that flows through the duct 80 from the inverter substrate 7a to the air duct D1 connected to the duct 80. The air guide duct D1 is provided from a discharge port D facing the heating coil 3a, and the air supplied from the duct 80 is used for cooling the heating coil 3a. Here, when the air flowing into the duct 80 from the inverter board 7a flows through the duct 80, the wind speed distribution toward the downstream side of the duct 80 is formed because the air flows with a substantially constant air passage cross-sectional area, and the wind pressure is maintained. The air can be blown to the heating coil 3a at a high wind speed. Therefore, the heat transfer between the heating coil 3a and the air is improved, and heat can be efficiently taken and cooled even with a small air volume.

Further, as described above, the substrate case 8 houses the substrates 7a and 7b and the fan device 9, and the substrate case 8 and the case lid 6 are combined up and down, and the intake opening H1 and the cooling air passage of the heating coil 3a are combined. It constitutes an air passage that is almost sealed except for the parts. The mating portion 6a of the substrate case 8 and the case lid 6 may be fixed by overlapping a part or the whole of the outer circumference as shown in the figure, or by forming a flange shape and widening the contact surface. Good. These are structural examples for suppressing air leakage from the gap between the mating portion 6a of the substrate case 8 and the case lid 6, for example, a structure in which a sponge-like sealing member is arranged on the mating portion 6a of the substrate case 8 and the case lid 6. It may be. The mating portion 6a can suppress leakage of air flowing through the substrate case 8 and improve the cooling efficiency of the substrate 7 on which the electronic component 71 is mounted and the heating coil 3a.

The board base 73 is an insulating member (resin member) for fixing the control board 7b. The substrate base 73 is, for example, supported in a plurality of ribs (not shown) protruding inward from the inner wall surface of the substrate case 8 and supported by screws, for example, and fixed in the substrate case 8. In this embodiment, the control board 7b arranged above the inverter board 7a is not provided with a dedicated cooling air passage, and the control board 7b generates less heat.

However, since the substrate base 73 to be stored and fixed in the substrate case 8 has a configuration in which a gap is easily provided in the fitting portion with the substrate case, the cooling air flowing into the control substrate 7b is easily secured and designed. be able to. Therefore, the board base 73 is arranged according to the size and shape of the control board 7b and the duct 80, and the notch portion 73a of the board base 73 and the inlet of the duct 80 are fitted and arranged.

FIG. 4 is a schematic view of a front cross section cut along the line CC shown in FIG. The heating chamber 50 in the grill 5 located on the left side of the front is, for example, a space for arranging cooked foods such as fish, and an electric heater (upper heater 51, lower heater 52) which is a heat source and fish and the like are placed. It has a grill 54 and a saucer 53 arranged below the grill 54. As described above, the heating chamber 50 is arranged in the left region inside the main body 1 in a plan view, and the internal saucer 53 and the like can slide in the front-rear direction with respect to the main body 1 in conjunction with the door portion 5a. There is.

The heat source of the heating chamber 50 is not limited to the electric heater, and the food may be heated by microwaves, steam, or a combination thereof. Alternatively, a temperature controller may be provided to heat the oven.

Inside the substrate case 8 and the case lid 6 located on the front right side of the grill storage 5, two substrates 7a and 7b are arranged so as to be stacked in the vertical direction of the main body 1. By placing the inverter board 7a on the bottom surface of the board case 8 and the control board 7b on the resin board base 73, the charging parts (not shown) of the boards 7a and 7b can be handled without directly touching the parts. Becomes easier. In this embodiment, the board base 73 is not provided on the inverter board 7a that can be directly installed on the board case 8, but the board base 73 is provided for each board so that the work at the time of assembly is good. May be good. Since the substrates 7a and 7b are arranged at intervals above and below, a discharge port 95 of the fan device 9 is provided in the gap, and cooling air is supplied. An air duct D1 is provided on the upper surface of the case lid 6 in accordance with the position of the duct 80, and the cooling air is guided to the discharge portion D below the heating coils 3a and 3b (FIG. 4). The discharge port 95 of the fan device 9 is arranged behind the inverter board 7a provided with the heat sink 79.

<Heating operation and air flow in the board case>
A pan to be cooked (not shown) is placed on the pan mounting portion 21 (corresponding to the heating coil 3a) on the right side of the top plate 2 shown in FIG. Start. The operation unit P0 is, for example, a touch key, and can be operated by touching the key printed on the top plate 2.

A high-frequency current is supplied from the inverter circuit of the inverter board 7a to the heating coil 3a located below the cooking pot in response to a command from a control device (for example, installed in the operation unit P0) to induce and heat the cooking pot. To do. When the cooking pot is induced and heated by the heating coil 3a, in addition to the heating coil 3a, the high heat generating element 72 and the electronic component 71 of the inverter board 7a constituting the inverter circuit also generate heat.

With the start of cooking, the fan device 9 is driven in response to a command from the control device. When the fan device 9 is driven, a negative pressure is generated on the intake port 9a side, and air is sucked from the intake opening H1. The air discharged from the discharge port 95 of the fan device 9 is blown toward the heat sink 79 provided in the gap between the substrate base 73 of the control board 7b and the inverter board 7a, and is on the inverter board 7a on which the inverter circuit of the heating coil 3a is mounted. Heat is absorbed from the heat sink 79.

The high heat generating element 72 is cooled by heat dissipation via the heat sink 79, and the other electronic components 71 mounted on the inverter board 7a are also cooled by heat exchange with air. The air that has cooled the inverter substrate 7a enters the duct 80 through the notch 73a of the substrate base 73, is guided to the discharge portion D of the air duct D1 above the case lid 6 via the duct 80, and is guided to the discharge portion D of the air duct D1 above the case lid 6 to heat the heating coil 3a. Flow toward. The air that has cooled the heating coil 3a cools the filter substrate 7d and is discharged through the exhaust opening H2.

Similarly, when using the grill storage 5, the door 5a is slid forward to pull out the saucer 53 and the grill 54, and then a heated object such as a fish is placed on the grill 54 to be placed in the heating chamber 50. The heat treatment is started by operating the operation unit P0 by the user. The heating of the upper heater 51 and the lower heater 52 is controlled by the relay of the control board 7b according to, for example, the type of the object to be heated and the thermal power set by the operation unit P0. Since the heating chamber 50 becomes hot when the grill storage 5 is used, the fan device 9 is driven in order to suppress the temperature rise of the parts around the heating chamber 50. The air supplied from the fan device 9 passes through a duct 80 provided between the grill storage 5 and the substrate 7, thermally shields the grill storage 5 and the substrate 7, and also heats the substrate case 8 and the case on the heating chamber 50 side. The wall surface of the lid 6 is cooled. Therefore, while keeping the heating chamber 50 at a high temperature and suppressing the temperature rise of the surrounding parts, the cooking is continued.

<Effect>
According to the present invention, the cooling air to the inverter substrate 7a arranged at the lower stage of the substrate case is guided by the duct 80 to the discharge portion D for cooling the heating coil 3 with a small ventilation resistance, and each component in the main body 1 is guided. Can be cooled efficiently. Further, when the grill is used, the duct 80 suppresses the heat transfer from the grill storage side to the substrate 7, the substrate temperature rise and the retention of hot air in the substrate case are suppressed, and an air-cooled structure capable of suppressing a failure can be realized.

In the second embodiment, the configurations of the substrate case 8 and the fan device 9 are different from those in the first embodiment, but the other parts are the same as those in the first embodiment. Therefore, the different parts will be described, and the description of the parts overlapping with the first embodiment will be omitted.

5 is an exploded perspective view of the substrate case and the parts housed in the case lid according to the second embodiment, FIG. 6 is a side sectional view of the induction heating cooker, and FIG. 7 is a schematic front sectional view of the induction heating cooker of FIG. It is a figure. The fan device 9 of this embodiment has a configuration in which the impeller 91 is arranged in a casing 93 composed of a scroll portion 8a and a bell mouth portion 8b. As shown in FIG. 6, the motor 92 is arranged above the motor base 90, that is, in the casing 93, and the motor 92 that generates heat can be efficiently cooled by the rotation of the impeller 91, which is reliable at high speed rotation. It becomes a high operation. Further, since the heavy motor 92 can be arranged on the bottom surface side of the substrate case 8, that is, the highly rigid portion on the bottom surface side of the main body, the structure is less likely to cause vibration. In this embodiment, FIGS. 6 and 7 are shown. The discharge portion 95 of the fan device 9 is provided so as to straddle the board base 73 on which the control board 7b is arranged, and the cooling air is supplied from the fan device 9 to both the inverter board 7a and the control board 7b. That is, the cooling air constitutes two systems of air passages.

One is that cooling air flows through the heat sink 79 in which the high heat generating element 72 is installed as in the first embodiment toward the inverter board 7a provided on the lower side of the board case 8, and the air that has passed through the heat sink 79 is the grill storage. It flows toward the duct 80 arranged on the 5 side. The duct 80 molded into the case lid 6 forms an air passage through which the air flowing into the inverter board 7a passes through the control board 7b and directly passes the air to the upper end of the case lid 6. As shown in FIG. 7, an air duct D1 for cooling the heating coil 3b on the left side is provided above the duct 80, and the cooling air blown from the fan device 9 to the inverter substrate 7a cools the heating coil 3b on the left side. It is used for.

The other constitutes a flow that flows toward the control board 7b provided on the upper side of the board case 8 and blows out from the discharge portion D of the case lid 6 provided below the heating coil 3a on the right side. That is, in this embodiment, the duct 80 is used to cool the inverter board 7a and the heating coil 3b on the left side, and the control board 7b and the heating coil 3a on the right side.

<Air passage configuration with fan device>
8 is a top sectional view of the substrate case of FIG. 6, and FIG. 9 is a top sectional view of the case lid of FIG. In this embodiment, the impeller 91 shown in FIG. 5 is surrounded by a casing 93 including a motor base 90, a scroll portion 8a, and a bell mouth portion 8b to form a fan device 9. A motor 92 is installed on the lower side of the motor base 90, and an impeller 91 is installed on the rotation shaft of the motor 92. Here, the rotation axis of the motor 92 is in the vertical direction of the main body 1 which is perpendicular to the arrangement surface of the substrate 7. The bell mouth portion 8b is a substantially circular intake port 9a smaller than the outer diameter of the impeller 91 (see FIG. 6). The air passage around the impeller 91 flows into the scroll portion 8a from the intake port 9a of the bell mouth portion 8b, and then blows out from the discharge port 95.

The fan device 9 has a configuration in which the impeller 91 is inserted into the scroll portion 8a integrally molded with the substrate case 8. In this embodiment, as shown in FIG. 8, the orthogonal flow path portion 93 is integrally molded behind the substrate storage portion 8e, and the scroll portion 8a constituting the wall surface of the orthogonal flow path portion 93 and the frame of the substrate case 8 are formed. The structure is such that the portion 8d is connected and supported by a plurality of ribs 8c. Therefore, in this structure, there are few connection paths for vibration transmission caused by minute eccentricity, surface runout, etc. of the impeller 91.

In this embodiment, the impeller 91 is a multi-blade fan, but an impeller whose intake direction (intake unit 9a) and discharge direction (discharge unit 95) are orthogonal to each other may be, for example, a centrifugal fan. The multi-blade fan is effective when increasing the height of the discharge port 95, and is suitable for this embodiment in which two air passages are used.

Further, in the case lid 6 of this embodiment, the space between the duct 80 and the discharge portion D is separated as shown in FIG. 9 when viewed from the discharge port 95. Similar to the first embodiment, the end portion of the duct 80 is in close contact with the cutout portion 73a (see FIG. 5) of the substrate base 73, and has a structure that suppresses air leakage at the joint. ..

<Modification example 1>
FIG. 10 is a modification of FIG. 8, and the configuration of the case lid 6 is different from that of FIG. 8, but the other parts are the same. Therefore, the different parts will be described, and the description of overlapping parts such as the air passage configuration in the fan device 9 will be omitted.

In this modification, the duct 80 of the case lid 6 is composed of a separate part from the case lid 6. That is, the duct 80 can be installed by inserting the case lid 6 from above the case lid 6 after attaching the case lid 6 to the substrate case 8. In this configuration, since the duct 80 is pressed against the notch 73a of the lower substrate base 73 to be assembled, it is possible to prevent the joint from leaking. The detachable duct 80 can be easily integrated with the air duct D1, and a configuration for efficiently guiding the cooling air without increasing the number of parts can be realized.

<Modification 2>
FIG. 11 is a modification of FIG. 8, and the configuration of the case lid 6 shown in FIG. 12 is different from that of FIG. 8, but the other parts are the same. Therefore, the different parts will be described, and the description of overlapping parts such as the air passage configuration in the fan device 9 will be omitted.

In this modification, the air passage of the case lid 6 that supplies the cooling air to the heating coil 3a on the right side via the control board 7b is a rib 8c that is aligned with the position of the discharge portion D. That is, the discharge portion D for supplying the cooling air to the heating coil 3 is provided not on the upper side but on the side side. This is a consideration against internal intrusion of liquid such as water due to a crack in the top plate 2 in the induction heating cooker. Since the discharge portion D can serve as an inlet for the liquid communicating with the substrate 7, the reliability of the induction heating cooker can be improved even with respect to a failure due to an external factor by this modification.

<Effect>
According to the present invention, air passages from the fan device 9 to the heating coils 3a and 3b and the substrates 7a and 7b can be individually provided to simplify the air passages and facilitate the supply of cooling air to the heating coils 3 downstream. .. Further, it is possible to provide an induction heating cooker in which the ventilation resistance of the air passage can be reduced by arranging the air passages in parallel and the operation noise is suppressed by reducing the load on the fan device 9.

In the third embodiment, the configurations of the case lid 6 and the fan device 9 are different from those in FIG. 5, but the other parts are the same as those in the second embodiment. Therefore, the different parts will be described, and the description of the parts overlapping with the second embodiment will be omitted.

FIG. 13 is an exploded perspective view of the substrate case of Example 3 and the parts housed in the case lid, and FIG. 14 is a schematic view of a side cross section of the induction heating cooker of Example 3. In this embodiment, the control board 7b installed on the board base 73 has a shape that matches the cutout portion 73a. The wider the mounting area of the electronic component on the substrate 7, the more likely the wiring pattern can be and the more stable the circuit can be configured in which noise is less likely to occur. Further, wirings such as the temperature sensor 34 (see FIG. 2), the operation unit P0, and the power switch P3 (see FIG. 1) provided in the heating coil 3 are connected to the control board 7b, and for example, the connector (not shown). ) Is arranged as a relay board 70 exposed to the outside of the case lid 6 on a part of the control board 7b, so that wiring at the time of assembly becomes easy. Here, by using the relay board 70 as a part of the control board 7b and partitioning the space with the case lid 6, components can be efficiently mounted without affecting the air passage in the board case.

Further, in the fan device 9 of this embodiment, the intake port 9a is located below the substrate case 8. The configuration in which the intake port 9a faces downward makes it more difficult for the liquid scattered from the intake opening H1 to enter, and the cause of failure can be suppressed. The present invention can be applied regardless of the type and arrangement of the fan device 9.

1 ... Main body, 2 ... Top plate, 3 ... Heating coil (3a, 3b), 5 ... Grill storage, 6 ... Case lid, 7 ... Substrate (7a, 7b), 7a ... Inverter board, 7b ... Control board, 8 ... Board case, 9 ... Fan device, 9a ... Intake port, 70 ... Relay board, 71 ... Electronic components, 72・ ・ ・ High heat generation element, 73 ・ ・ ・ Board stand, 73a ・ ・ ・ Notch, 79 ・ ・ ・ Heat sink, 80 ・ ・ ・ Duct, 90 ・ ・ ・ Motor stand, 91 ・ ・ ・ Impeller, 92 ・ ・-Motor, 93 ... Casing, D ... Discharge part, D1 ... Air duct, H1 ... Intake opening, H2 ... Exhaust opening, H3 ... Exhaust air guide

Claims (4)

With the main body
A top plate installed on the upper surface of the main body and
At least two heating coils on the left and right below the top plate,
A grill storage provided below one of the two heating coils on the left and right, and
A board case for storing a board provided on either the left or right side of the grill, and a board case.
An inverter board equipped with an inverter circuit that supplies high-frequency power to the heating coil housed in the board case, and
A control board that supplies and controls power to the grill that is housed in the board case,
A case lid that covers the substrate case from above and mounts the heating coil, and
The substrate case is provided with a fan device for sucking cooling air.
The inverter board and the control board are housed in the board case in two upper and lower stages.
An induction heating cooker characterized in that a duct that flows from below the substrate case to the upper surface of the case lid is arranged in a gap between the grill and the inverter circuit. The induction heating cooker according to claim 1, wherein the duct is integrally molded with the case lid. The inverter board is arranged on the lower side of the board case, the control board is placed on the upper part of the board case via a resin base, a notch is provided in the resin base, and the notch and the duct are formed. The induction heating cooker according to claim 1 or 2, wherein the induction heating cooker is arranged so as to be fitted. The fan device is characterized in that it is connected to an air passage that supplies cooling air from the inverter board to the heating coil on the left side via the duct and an air passage that supplies cooling air from the control board to the heating coil on the right side. The induction heating cooker according to any one of claims 1 to 3.

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