JP2023099921A - rice cooker - Google Patents

Abstract

To obtain a rice cooker that can improve heating power by improving cooling performance for cooling a power supply board.SOLUTION: A rice cooker comprises: a main body having a cylindrical shape of which an upper end part and a lower end part are open; a bottom case covering the opening of the lower end part of the main body, and in which an intake port and an exhaust port are formed; an inner pot detachably housed inside the main body; a heating part arranged in the main body, and for heating the inner pot; a power supply board 20 arranged in the main body, and for driving the heating part; a heat dissipation fin 32 arranged on the power supply board; and a cooling fan 21 arranged in the intake port of the bottom case, and for blowing cooling air taken from the intake port, toward the heat dissipation fin and the power supply board. When a width direction X of the main body is defined as a first direction, a plurality of heat dissipation members of the heat dissipation fin are arranged in parallel at intervals in the first direction, and a width L1 of the cooling fan in the first direction is larger than a width L2 of the heat dissipation fin in the first direction.SELECTED DRAWING: Figure 13

Description

The present disclosure relates to a rice cooker having a power supply board.

As a conventional example, there is a rice cooker that has an air intake port and a cooling fan on the bottom portion of the main body rear and cools a power supply substrate arranged on the main body rear (see, for example, Patent Document 1).

The rice cooker described in Patent Document 1 detachably accommodates a bottomed cylindrical inner pot that accommodates food to be cooked, such as rice, inside an inner case provided in a main body. The rice cooker described in Patent Document 1 has an induction heating coil that heats the bottom of the inner pot. The power board uses power from an external power source, such as a commercial power source, to power the induction heating coil. Thereby, the inner pot receives an induced current from the induction heating coil and generates heat by electromagnetic induction. The heat is generated to heat and cook the food contained in the inner pot.

JP 2012-75510 A

In the rice cooker described in Patent Document 1, when an attempt is made to increase the heating amount of the induction heating coil, the heat generation amount of the power supply board also increases at the same time. was there.

The present disclosure has been made to solve such problems, and aims to obtain a rice cooker that can improve heating power by improving the cooling performance of cooling the power supply board. .

A rice cooker according to the present disclosure includes a main body having a cylindrical shape with an upper end and a lower end opened, a bottom case covering the opening at the lower end of the main body and having an air intake port and an air outlet, and an inner pot detachably housed inside; a heating unit arranged in the main body for heating the inner pot; a power substrate arranged in the main body for driving the heating unit; and a cooling fan disposed at the air inlet of the bottom case and blowing cooling air taken in from the air inlet toward the heat radiating fins and the power supply substrate, wherein the width direction of the main body is When the first direction is assumed to be the first direction, the heat radiation fins have a plurality of heat radiation members juxtaposed at intervals in the first direction, and the width of the cooling fan in the first direction is equal to the first width of the heat radiation fins. It is greater than the width in the direction.

According to the rice cooker according to the present disclosure, when the width direction of the main body is taken as the first direction, the width of the cooling fan in the first direction is made larger than the width of the heat radiating fins in the first direction, so that the wind force of the cooling fan is increased. In addition, the function of the heat radiation fins is effectively used to improve the cooling performance for cooling the power supply board. By improving the cooling performance in this way, the power supply board can be cooled efficiently, so even if the heating power of the rice cooker is increased, the temperature rise of the power supply board can be suppressed. As a result, it becomes possible to improve the heating power of the rice cooker.

1 is a perspective view showing the appearance of a rice cooker according to Embodiment 1; FIG. 1 is a cross-sectional view showing the configuration of a rice cooker according to Embodiment 1; FIG. 1 is a perspective view showing a configuration of a rice cooker according to Embodiment 1; FIG. 4 is a perspective view showing the configuration of a bottom case provided in the rice cooker according to Embodiment 1. FIG. 2 is a perspective view showing the configuration of a power supply board provided in the rice cooker according to Embodiment 1. FIG. 2 is a perspective view showing the configuration of a power supply board provided in the rice cooker according to Embodiment 1. FIG. 4 is a front view showing the front of the power supply board provided in the rice cooker according to Embodiment 1. FIG. 3 is a perspective view showing a power supply board provided in the rice cooker according to Embodiment 1. FIG. FIG. 4 is an explanatory diagram showing the positional relationship among the power supply board, heat radiation fins, and cooling fan in the rice cooker according to Embodiment 1; FIG. 4 is an explanatory diagram showing the positional relationship among the power supply board, heat radiation fins, and cooling fan in the rice cooker according to Embodiment 1; FIG. 4 is an explanatory diagram showing the positional relationship among the power supply board, heat radiation fins, and cooling fan in the rice cooker according to Embodiment 1; FIG. 4 is an explanatory diagram showing the positional relationship among the power supply board, heat radiation fins, and cooling fan in the rice cooker according to Embodiment 1; FIG. 4 is an explanatory diagram showing the size relationship in the width direction between the radiation fins and the cooling fan in the rice cooker according to Embodiment 1; FIG. 2 is a perspective view showing the configuration of a fin cover in the rice cooker according to Embodiment 1; FIG. 2 is a perspective view showing the configuration of a fin cover in the rice cooker according to Embodiment 1; 4 is a plan view showing the configuration of the fin cover in the rice cooker according to Embodiment 1. FIG. FIG. 2 is a perspective view showing the configuration of a fin cover in the rice cooker according to Embodiment 1; FIG. 2 is a perspective view showing the configuration of a fin cover in the rice cooker according to Embodiment 1; 4 is a front view showing the rear portion of the fin cover provided in the rice cooker according to Embodiment 1. FIG. FIG. 20 is a partially enlarged view of FIG. 19; 4 is a perspective view showing the rear portion of the fin cover provided in the rice cooker according to Embodiment 1. FIG. FIG. 22 is a partially enlarged view of FIG. 21; FIG. 4 is an explanatory diagram showing the size relationship between the size in the width direction and the size in the height direction of the heat radiating fins in the rice cooker according to Embodiment 1; FIG. 3 is a diagram in which arrows indicating the direction of flow of cooling air are added to FIG. 2 ; 8 is a diagram in which arrows indicating the direction of flow of cooling air are added to FIG. 7; FIG. FIG. 21 is a diagram in which arrows indicating the direction of flow of cooling air are added to FIG. 20 ; FIG. 4 is a cross-sectional view showing a method of arranging a cooling fan provided in the rice cooker according to Embodiment 1; FIG. 28 is a partially enlarged view of FIG. 27; FIG. 10 is a perspective view showing a configuration of a fin cover provided in the rice cooker according to Modification 1 of Embodiment 1; FIG. 10 is a perspective view showing a state in which the fin cover is mounted on the power supply board in the rice cooker according to Modification 1 of Embodiment 1; FIG. 9 is a plan view showing the configuration of a fin cover provided in the rice cooker according to Modification 1 of Embodiment 1; FIG. 9 is a plan view showing the configuration of a fin cover provided in the rice cooker according to Modification 1 of Embodiment 1;

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the rice cooker which concerns on this indication is described with reference to drawings. The present disclosure is not limited to the following embodiments, and various modifications can be made without departing from the gist of the present disclosure. In addition, the present disclosure includes all combinations of configurations that can be combined among configurations shown in the following embodiments and modifications thereof. Also, in each figure, the same reference numerals denote the same or corresponding parts, which are common throughout the specification. In each drawing, the relative dimensional relationship, shape, etc. of each component may differ from the actual one. In each drawing, Z is the height direction of the rice cooker, and Y is the depth direction of the rice cooker. Also, X is the width direction of the rice cooker. The height direction Z is, for example, the vertical direction. In the height direction Z, Z1 is the upward direction and Z2 is the downward direction when the rice cooker is arranged in the normal direction. In the depth direction Y, Y1 is the front direction (or front side) of the rice cooker, and Y2 is the back direction (or back side) of the rice cooker. In the width direction X, X1 is the right direction (or right side) when the rice cooker is arranged in the normal direction and the rice cooker is viewed from the front, and X2 is the left direction (or left side). The width direction X is sometimes called the first direction. The height direction Z is sometimes called the second direction. The depth direction Y is sometimes called a third direction.

Embodiment 1.
FIG. 1 is a perspective view showing the appearance of a rice cooker according to Embodiment 1. FIG. 2 is a cross-sectional view showing the configuration of the rice cooker according to Embodiment 1. FIG. FIG. 2 shows a cross-sectional shape taken along a plane parallel to the YZ plane. As shown in FIGS. 1 and 2, the rice cooker 100 includes a main body 1 which is an outer case, an inner case 2 fixed inside the main body 1, an induction heating coil 3, a temperature sensor 4, and a bottom case 8. and have

A main body 1 forming a side surface of the rice cooker 100 has a cylindrical shape. The body 1 may be rectangular in plan view, or may be circular or elliptical. Alternatively, the main body 1 may have a rectangular rear side and a circular or semi-circular front side in plan view. The upper and lower ends of body 1 are open. A bottom case 8 is provided at the lower end of the main body 1 . The bottom case 8 is attached to the main body 1 so as to cover the open lower end of the main body 1 . The main body 1 and the bottom case 8 form an outer shell of a cylindrical rice cooker 100 with a bottom. The bottom case 8 is made of synthetic resin such as PP (polypropylene). The main body 1 is made of resin such as PC (polycarbonate) or ABS (acrylonitrile, butadiene, styrene). In addition, the main body 1 is not limited to resin, and may be formed of a metal member such as stainless steel.

The inner case 2 has a bottomed cylindrical shape with an open upper end. The inner case 2 has a circular shape, a substantially circular shape, or an elliptical shape in plan view. Inside the inner case 2, an inner hook 5, which will be described later, is detachably accommodated.

The induction heating coil 3 is a coil for electromagnetic induction heating provided on the outer wall of the inner case 2 . The induction heating coil 3 is arranged on the bottom of the inner case 2 and on the side surface near the bottom. The induction heating coil 3 is spirally wound, for example. High-frequency current is supplied to the induction heating coil 3 via, for example, a rectifier circuit and an inverter circuit provided on the power supply board 20 . The induction heating coil 3 constitutes a “heating section” that heats the inner pot 5 . The “heating unit” is not limited to the induction heating coil 3, and may be of any other configuration as long as it can heat the inner pot 5.

The temperature sensor 4 is provided on a lid body 7 which will be described later. The lid 7 is attached to the main body 1 so as to be openable and closable so as to cover the open upper end of the main body 1 . A temperature sensor 4 detects the temperature inside the inner pot 5 . The temperature sensor 4 is arranged, for example, so as to pass through a through-hole formed in an inner lid 7b that constitutes the lid 7. As shown in FIG. The number of temperature sensors is not limited to one, and in addition to the temperature sensor 4 on the lid side, a temperature sensor on the pot bottom side may be provided at the bottom of the inner case 2 .

Furthermore, the rice cooker 100 has an inner pot 5 , a hinge portion 6 , a lid body 7 and a lid heater 9 .

The inner pot 5 has a bottomed tubular shape with an open upper end. The inner pot 5 has a circular shape, a substantially circular shape, or an elliptical shape in plan view. The inner hook 5 is detachably housed in the inner case 2 provided in the main body 1 . The inner pot 5 accommodates food to be cooked, such as rice and water. The inner pot 5 receives an induced current from the induction heating coil 3, and the inner pot 5 itself generates heat due to electromagnetic induction. The food to be heated and cooked in the inner pot 5 is cooked by the heat generation. A flange portion 50 is provided on the periphery of the opening of the inner hook 5 . The flange portion 50 is provided along the circumferential direction of the opening of the inner hook 5 over the entire circumference of the opening. As shown in FIG. 2, the flange portion 50 has an L-shaped cross section. The flange portion 50 is composed of a horizontal portion 50a extending horizontally from the peripheral edge of the opening of the inner hook 5 and a vertical portion 50b standing upward Z1 from the outer peripheral edge of the horizontal portion 50a. It is configured. A horizontal portion 50 a of the flange portion 50 extends in the radial direction of the inner hook 5 from the peripheral portion of the opening of the inner hook 5 toward the outside of the inner hook 5 . That is, the horizontal portion 50a is provided so as to be parallel to the XY plane. The horizontal portion 50a has a donut shape in plan view. The vertical portion 50b is provided on the outer peripheral edge of the horizontal portion 50a. The vertical portion 50b is erected from the outer peripheral edge of the horizontal portion 50a in the upward direction Z1. The extending direction of the vertical portion 50b and the extending direction of the horizontal portion 50a intersect with each other, for example, are perpendicular to each other.

The hinge portion 6 is provided on the back portion of the main body 1 . The lid 7 is attached to the main body 1 via the hinge portion 6 so as to be openable and closable. The lid body 7 is composed of an outer lid 7a, an inner lid 7b, and lid packing (not shown).

The outer lid 7a is provided on the main body 1 via a hinge portion 6 so as to be openable and closable. The outer lid 7a is arranged so as to cover the opening at the upper end of the main body 1 .

The inner lid 7b is a lid that covers the inner pot 5 and is arranged inside the outer lid 7a. A lid packing (not shown), which is a sealing material, is attached to the peripheral portion of the inner lid 7b. The lid packing is composed of an elastic member such as silicone rubber. The lid packing ensures sealing between the flange portion 50 of the inner pot 5 and the inner lid 7b. The inner lid 7b is attached to the inner wall surface of the outer lid 7a by the user when the outer lid 7a is in the open state. As a result, the outer lid 7a and the inner lid 7b are connected to each other, and when the outer lid 7a is opened and closed, the inner lid 7b is opened and closed simultaneously with the outer lid 7a. The inner lid 7b and the outer lid 7a constitute a lid body 7 that covers the inner pot 5. As shown in FIG. The inner lid 7b is detachably attached to the outer lid 7a, and the user removes the inner lid 7b from the outer lid 7a when cleaning the inner lid 7b.

The outer lid 7a is arranged above the inner lid 7b so as to cover the inner lid 7b. The outer lid 7a is provided on the main body 1 via a hinge portion 6 so as to be openable and closable. The outer lid 7a is arranged to cover the opening of the main body 1 and the opening of the inner hook 5 in the closed state. In addition, when the outer lid 7a is open, the food to be cooked can be put in and taken out of the inner pot 5. As shown in FIG. Furthermore, when the outer lid 7a is open, the inner pot 5 itself can be taken in and out from the main body 1.例文帳に追加

The lid heater 9 is provided inside the lid body 7 . As described above, since the induction heating coil 3 is arranged below the inner pot 5, the temperature of the upper portion of the inner pot 5 increases to It tends to be lower than the temperature of Therefore, in Embodiment 1, the lid heater 9 is arranged inside the lid body 7 . A lid heater 9 heats the upper portion of the inner pot 5 . By using both the induction heating coil 3 and the lid heater 9, temperature unevenness in the inner pot 5 and condensation on the inner lid 7b can be suppressed. As a result, the rice can be cooked deliciously, and the deliciousness of the rice can be maintained even during heat retention.

Furthermore, the rice cooker 100 has a power supply board 20, a cooling fan 21, and heat radiation fins 32 (see FIG. 5). As shown in FIG. 2 , the power board 20 is arranged on the rear surface of the main body 1 . The power substrate 20 is erected in the Z direction. The power supply substrate 20 is arranged such that its main surface (that is, the mounting surface) is parallel or substantially parallel to the height direction Z and perpendicular or substantially perpendicular to the XY plane. The power supply board 20 supplies high-frequency current to the induction heating coil 3 using power from an external power supply such as a commercial power supply to drive the induction heating coil 3 .

The radiation fins 32 are arranged on the power supply board 20 . The heat dissipation fins 32 dissipate heat from heat-generating components mounted on the power supply board 20 to cool the power supply board 20 . The radiation fins 32 will be described later. Further, as shown in FIG. 2, the cooling fan 21 is arranged below the power supply substrate 20 . The cooling fan 21 is arranged with respect to an air intake port 30 (described later) formed in the bottom case 8 . Cooling fan 21 blows outside air (cooling air) taken in from intake port 30 toward power supply board 20 and heat dissipation fins 32 to cool power supply board 20 and heat dissipation fins 32 .

The bottom case 8 is provided with an intake port 30 , an exhaust port 31 , and a cord reel 22 . The intake port 30 takes in cooling air for cooling the power supply substrate 20 and the heat radiation fins 32 from the outside, as described above. The exhaust port 31 discharges the cooling air after cooling the power supply substrate 20 and the heat radiation fins 32 to the outside. A power cord having one end connected to a power plug 23 is accommodated in the cord reel 22 . The other end of the power cord is connected to the power substrate 20 . The power plug 23 is detachably connected to an external power source such as a commercial power source.

Further, as shown in FIGS. 1 and 2 , an operation display section 24 is provided on the top surface of the lid 7 . The operation display unit 24 is provided with switches, various buttons, and a display screen such as a display. The user can cause the rice cooker 100 to perform various operations by operating various buttons on the operation display unit 24 . The display screen also displays the state of cooking with heat, the content of the cooking menu set by the user's operation, and the like. An operation board 25 is connected to the operation display section 24 . The content of the operation on the operation display unit 24 is transmitted to the control unit (not shown) via the operation board 25 .

Detection results of the temperature sensor 4 and other sensors are input to the control unit. In addition, various settings such as a heat cooking menu input by the user to the operation display unit 24 are transmitted to the control unit. The control unit controls operations of the power supply board 20 and the cooling fan 21 based on the detection results of the temperature sensor 4 and other sensors and various settings input to the operation display unit 24 . A control part is comprised from a processor and memory, for example. Each function of the control unit is implemented by the processor executing a program stored in the memory.

Next, the operation of rice cooker 100 will be described. When operating the rice cooker 100 , the user first puts ingredients such as rice and water into the inner pot 5 . These ingredients are the food to be cooked by the rice cooker 100 .

After that, when the user holds the flange portion 50 of the inner hook 5 and places the inner hook 5 on the inner case 2 and closes the outer lid 7a, the lid packing of the inner lid 7b is pushed into the flange portion 50 of the inner hook 5. , and the internal space of the rice cooker 100 is hermetically sealed.

As described above, the outer lid 7a is rotatable with the hinge portion 6 as a starting point, and opens and closes the opening at the upper end portion of the main body 1. As shown in FIG. The outer lid 7a is always biased by the hinge portion 6 in the opening direction. The outer lid 7a in the closed state is locked to the main body 1 by, for example, a latch portion (not shown) provided on the front surface of the outer lid 7a. When the user presses a lid open button (not shown), the latch portion that locks the outer lid 7a and the main body 1 is released, and the biasing force of the hinge portion 6 opens the outer lid 7a. become.

Next, when the user selects a rice cooking menu on the operation display unit 24 and turns on the switch of the operation display unit 24, rice cooking in the rice cooker 100 is started. Although FIG. 1 shows an example in which the operation display unit 24 is installed on the outer lid 7a, it is not limited to this case, and the operation display unit 24 is installed on the front surface of the main body 1. good too. Also, the operation display unit 24 may be provided at a location other than the main body 1 . That is, if the rice cooker 100 has a remote controller (not shown), the remote controller may be provided with the operation display unit 24 . Alternatively, the operation display unit 24 may be provided as an application program in a portable mobile terminal such as a smart phone carried by the user.

When the rice cooker 100 starts cooking, the induction heating coil 3 is supplied with a high-frequency current from the power supply board 20 . As a result, a high-frequency magnetic field is generated from the induction heating coil 3, and the surface of the inner pot 5 facing the heating coil (that is, the bottom surface of the inner pot 5) magnetically coupled to the induction heating coil 3 is excited, and the bottom portion of the inner pot 5 is excited. Eddy currents are induced in Joule heat is generated by this eddy current and the resistance of the inner pot 5, and the bottom surface of the inner pot 5 is heated to heat the food.

Next, the configuration of the bottom case 8 will be described with reference to FIGS. 3 and 4. FIG. 3 is a perspective view showing the configuration of the rice cooker according to Embodiment 1. FIG. 4 is a perspective view showing the configuration of the bottom case provided in the rice cooker according to Embodiment 1. FIG. FIG. 3 shows the state of the rice cooker 100 viewed from the downward direction Z2. Therefore, it should be noted that the directions of the upward direction Z1 and the downward direction Z2 are opposite to those in FIG. FIG. 4 shows the bottom case 8 removed from the main body 1 as viewed from above Z1. In FIG. 4, the directions of the upward direction Z1 and the downward direction Z2 are the same as in FIG.

The bottom case 8 is attached to the main body 1 so as to cover the opening at the lower end of the main body 1, as described above. As shown in FIGS. 3 and 4, the above-described cord reel 22 is provided in the central portion of the bottom case 8 . In addition, in the depth direction Y of the bottom case 8, an air intake port 30 is provided in a region on the back side of the main body 1 (closer to the back direction Y2). Further, in the bottom case 8, an exhaust port 31 is provided in a region on the front side of the main body 1 (closer to the front direction Y1). Moreover, as shown in FIGS. 2 and 4 , a cooling fan 21 is provided above the intake port 30 . Both the intake port 30 and the exhaust port 31 have a plurality of slits penetrating through the plate thickness of the bottom case 8 . The inside and outside of the bottom case 8 are communicated through these slits, and the cooling airflow can flow through these slits with reduced pressure loss. By providing a plurality of slits in the intake port 30 and the exhaust port 31 , foreign matter such as dust can be prevented from entering the main body 1 from the outside through the intake port 30 and the exhaust port 31 .

Next, the configuration of the power supply substrate 20 and the radiation fins 32 will be described with reference to FIGS. 5 and 6. FIG. 5 and 6 are perspective views showing the configuration of the power supply board provided in the rice cooker according to Embodiment 1. FIG. FIG. 5 shows the power supply board 20 viewed from the power supply board surface portion 201 side, which is the mounting surface on which the components 205 are mounted. The side of the power supply board surface portion 201 is hereinafter referred to as the front side of the power supply board 20 . FIG. 6 shows a state in which the power supply board 20 is viewed from the back surface portion 204 side of the power supply board 20 . At least one of the plurality of components 205 mounted on the power supply substrate surface portion 201 is a heat-generating component such as a semiconductor switching element that constitutes an inverter circuit and a rectifier circuit. Also, at least one of the plurality of components 205 mounted on the power supply substrate surface portion 201 is a consumable component such as an electrolytic capacitor that is easily damaged by heat and the life of the component is likely to be affected by heat. Since failure of the power supply board 20 leads to failure of the entire rice cooker 100 , it is important for the rice cooker 100 to improve the cooling performance of the power supply board 20 .

As shown in FIGS. 5 and 6, the power supply board 20 has a box shape as a whole. The power board 20 has a power board surface portion 201 on which components 205 are mounted, a top surface portion 202 , a pair of side surface portions 203 , and a back surface portion 204 . The power supply substrate 20 has an open bottom end. A cooling fan 21 is arranged in the opening at the lower end of the power supply board 20, as shown in FIGS. 9 and 10 described later. Further, the power supply board 20 is configured by a back surface member 200 having an open front surface and a plate-like back surface. The front side surface of the back member 200 is the above-described power supply board surface portion 201 , and the back side surface of the back member 200 is the above-described back portion 204 . In this way, the power supply board 20 has a box shape with at least a portion open, and the power supply board surface portion 201, which is the mounting surface, forms a part of the box shape of the power supply board 20. As shown in FIG. As shown in FIG. 5 , the heat dissipation fins 32 are arranged in the central portion of the power supply substrate surface portion 201 of the power supply substrate 20 . The heat dissipation fins 32 are arranged in the central portion of the power supply substrate surface portion 201 in the width direction X, but are arranged on the lower Z2 side of the power supply substrate surface portion 201 in the height direction Z. As shown in FIG. Therefore, a space is formed between the upper end portion of the radiation fins 32 and the upper surface portion 202 of the power supply board 20 . A space is also formed between the side surface portion of the radiation fins 32 and the side surface portion 203 of the power supply board 20 . That is, a U-shaped space is formed so as to cover the upper and side portions of the radiation fins 32, and the cooling air flows through the space (see arrow D in FIG. 25). How the cooling air flows will be described later.

The heat radiating fins 32 have a plurality of heat radiating members 32a arranged side by side with an interval W2 (see FIG. 31) in the width direction X, and a base portion 32b to which the heat radiating members 32a are cantilevered. . The base 32b has, for example, a rectangular plate-like shape. The plurality of heat radiating members 32a protrude from the base portion 32b toward the back direction Y2 of the depth direction Y. As shown in FIG. The plurality of heat dissipation members 32a are arranged parallel to each other. Each of the heat dissipation members 32a has a plate-like shape. The longitudinal direction of the heat radiating member 32a extends along the height direction Z, and the short direction of the heat radiating member 32a extends along the depth direction Y. As shown in FIG. The heat radiating member 32a and the base 32b are arranged in directions crossing each other. The heat radiating member 32a and the base 32b are, for example, orthogonal to each other. The heat radiation fins 32 are attached to the power supply substrate surface portion 201 of the power supply substrate 20 by means of attachments 206 such as screws (see FIG. 7). Therefore, in the central portion of the heat radiating fins 32 in the width direction X, the space W1 for arranging the heat radiating member 32a is larger than the space W2 for the other portions in order to secure a space for arranging the fixture 206. ing. The heat radiation fins 32 are made of metal with high thermal conductivity such as aluminum.

7 is a front view showing the front of the power board provided in the rice cooker according to Embodiment 1. FIG. 8 is a perspective view showing a power supply board provided in the rice cooker according to Embodiment 1. FIG. 7 and 8 show a state in which the power supply board 20 is mounted on the main body 1 of the rice cooker 100. FIG. 7 and 8 show a part of the interior of the main body 1 as seen through for explanation. As shown in FIGS. 7 and 8, the power supply board 20 is arranged on the rear surface of the main body 1 . A cooling fan 21 is arranged below the power supply board 20 . An intake port 30 provided in the bottom case 8 is provided below the cooling fan 21 . Further, as shown in FIG. 7, the heat dissipation fins 32 are attached to the power supply substrate surface portion 201 of the power supply substrate 20 with attachments 206 such as screws.

9 to 12 are explanatory diagrams showing the positional relationship among the power supply board, heat radiation fins, and cooling fan in the rice cooker according to Embodiment 1. FIG. 9 shows the state of the power supply board 20 viewed from the front side, and FIG. 10 shows the state of the power supply board 20 viewed from the rear side. 11 is a perspective view showing a cross section of the power supply substrate 20 cut along the XY plane passing through point A in FIG. FIG. 12 is a plan view showing a cross section of the power substrate cut along the XY plane passing through point A in FIG. A point A is a point positioned toward the downward direction Z2 from the central portion of the power supply board 20 in the height direction Z. As shown in FIG.

As shown in FIG. 12, the back surface member 200 composed of the power supply board surface portion 201 and the back surface portion 204 of the power supply substrate 20 is arranged at the central portion in the depth direction Y of the cooling fan 21 in plan view. As shown in FIG. 10, the back member 200 of the power supply board 20 is formed in a plate shape as a whole and has a rectangular shape when viewed from the back side. Further, the back member 200 extends along the width direction X in a plan view, as shown in FIG. 12 . As shown in FIG. 10, the back member 200 is erected from the upper surface of the cooling fan 21 in the upward direction Z1. As shown in FIG. 12, the cooling fan 21 has a rectangular shape in plan view. As shown in FIG. 12, the rear member 200 of the power supply board 20 is arranged so as to cross the central portion of the cooling fan 21 in the Y direction in the X direction. Cooling fan 21 blows outside air (cooling air) sucked from air inlet 30 toward power supply board 20 and heat radiation fins 32 . The cooling air blown by the cooling fan 21 hits both the power supply substrate surface portion 201 and the rear surface portion 204 of the power supply substrate 20 . The details of how the cooling air flows will be described later.

FIG. 13 is an explanatory diagram showing the size relationship in the width direction between the radiation fins and the cooling fan in the rice cooker according to Embodiment 1. FIG. As shown in FIG. 13, both the cooling fan 21 and the heat radiation fins 32 have a rectangular shape when viewed from the front. At this time, the size of the cooling fan 21 in the width direction X is defined as width L1, and the size of the heat radiation fin 32 in the width direction X is defined as width L2. As shown in FIG. 13, the width L1 of the cooling fan 21 is larger than the width L2 of the radiation fins 32. As shown in FIG. In conventional rice cookers, the width of the cooling fan and the width of the radiation fins are the same. In Embodiment 1, cooling fan 21 having a size larger than radiation fins 32 is used so that width L1 of cooling fan 21 is greater than width L2 of radiation fins 32 . In general, as the size of the cooling fan 21 increases, the amount of cooling air taken in by the cooling fan 21 from the intake port 30 increases accordingly. Thereby, the cooling performance for cooling the power supply board 20 is improved.

14 and 15 are perspective views showing the configuration of the fin cover in the rice cooker according to Embodiment 1. FIG. Moreover, FIG. 16 is a plan view showing the configuration of the fin cover in the rice cooker according to Embodiment 1. As shown in FIG. As shown in FIGS. 14 to 16, the rice cooker 100 has a fin cover 33 that covers the radiation fins 32. As shown in FIGS. The fin cover 33 is arranged so as to cover the radiation fins 32 and is fixed to the power supply substrate surface portion 201 of the power supply substrate 20 . Specifically, as shown in FIG. 14, the front side opening of the power supply board 20 and the opening of the fin cover 33 are arranged to face each other, and as shown in FIGS. , a fin cover 33 is attached so as to cover the radiating fins 32 .

17 and 18 are perspective views showing the configuration of the fin cover in the rice cooker according to Embodiment 1. FIG. 17 shows the state of the fin cover 33 viewed from the rear portion 330 side, and FIG. 18 shows the state of the fin cover 33 viewed from the front side. As shown in FIGS. 17 and 18, the fin cover 33 has a back portion 330 and a pair of side portions 331. As shown in FIGS. The side portions 331 are arranged to face each other. The side portion 331 extends in the height direction Z. As shown in FIG. In addition, the rear portion 330 also extends in the height direction Z. As shown in FIG. The fin cover 33 has a box shape as a whole, and is open at an upper end portion 334, a lower end portion 335, and a front portion. Both the back portion 330 and the side portion 331 are rectangular plate members. The back portion 330 and the side portion 331 are arranged adjacent to each other and joined together. The back surface portion 330 and the side surface portion 331 are arranged in directions crossing each other. For example, the back surface portion 330 and the side surface portion 331 are perpendicular to each other. Therefore, the upper end portion 334 of the fin cover 33 has a U-shape in plan view. A tapered portion 332 is provided at the lower end of each side portion 331 . The tapered portion 332 is arranged so as to be inclined with respect to the height direction Z. As shown in FIG. The tapered portions 332 are formed in a tapered shape such that the distance therebetween gradually decreases in the upward direction Z1. In other words, the tapered portions 332 are inclined so as to diverge in the downward direction Z2. That is, the tapered portion 332 is formed so as to widen toward the outside of the fin cover 33 as it goes in the downward direction Z2. Back portion 330 is joined to side portion 331 and tapered portion 332 . Therefore, the lower end region 330a of the back surface portion 330 gradually increases in size in the width direction X in an inversely tapered manner toward the downward direction Z2 in accordance with the tapered portion 332 . That is, the lower end region 330a of the back surface portion 330 has a trapezoidal shape in which the upper side is shorter than the lower side. As shown in FIG. 17, a space 337 is formed inside the fin cover 33 . As shown in FIGS. 14 to 16, the space 337 accommodates the radiating fins 32 . Further, as shown in FIGS. 17 and 18, the fin cover 33 is provided with projections 336 for fixing the fin cover 33 to the power supply board 20 as required.

19 is a front view showing the rear portion of the fin cover provided in the rice cooker according to Embodiment 1. FIG. 20 is a partially enlarged view of FIG. 19. FIG. 19 and 20 show the fin cover 33 mounted on the main body 1 of the rice cooker 100. FIG. In FIGS. 19 and 20, a part of the configuration is seen through for explanation. The power supply board 20 and the fin cover 33 are actually arranged inside the main body 1 and are not exposed to the outside, as shown in FIG. The fin cover 33 is arranged so as to cover the radiation fins 32 (see FIG. 9) and is fixed to the power supply board surface portion 201 of the power supply board 20 . As shown in FIGS. 19 and 20 , a fin cover 33 is arranged in the central portion of the power supply board surface portion 201 of the power supply board 20 so as to cover the radiation fins 32 . The fin cover 33 is arranged at the central portion in the width direction X, but is arranged on the lower Z2 side of the power supply substrate surface portion 201 in the height direction Z. As shown in FIG.

21 is a perspective view showing the rear portion of the fin cover provided in the rice cooker according to Embodiment 1. FIG. 22 is a partially enlarged view of FIG. 21. FIG. In FIGS. 21 and 22, a part of the configuration is seen through for explanation. As shown in FIG. 22 , the fin cover 33 has a first opening 40 through which the cooling air taken in by the cooling fan 21 is taken into the power supply board 20 . Further, the fin cover 33 has a second opening 41 through which the cooling air taken in from the first opening 40 cools the heat radiating fins 32 and then is discharged. The first opening 40 consists of the lower end 335 of the fin cover 33 shown in FIGS. 17 and 18, and the second opening 41 consists of the upper end 334 of the fin cover 33 shown in FIGS. there is Both the first opening 40 and the second opening 41 have a rectangular shape in plan view. At this time, assuming that the opening area of the first opening 40 is an opening area R1 and the opening area of the second opening 41 is an opening area R2, the opening area R2 of the second opening 41 is, as shown in FIG. It is smaller than the opening area R1 of the first opening 40 .

Also, the first opening 40 of the fin cover 33 is formed to match the width of the cooling fan 21 as shown in FIGS. 20 and 22 . Therefore, the size of the first opening 40 of the fin cover 33 in the width direction X is the same as the width L1 of the cooling fan 21 (see FIG. 13). As a result, the cooling air discharged from the large-diameter cooling fan 21 is efficiently taken into the fin cover 33 through the first openings 40 and flows into the radiating fins 32 . Further, since the cooling fan 21 is covered with the fin cover 33 on the side of the power board surface portion 201 of the power board 20, it is possible to suppress the return of the cooling air to the intake side of the cooling fan 21. FIG. As a result, loss of cooling air can be eliminated.

On the other hand, the second openings 41 of the fin cover 33 are formed to match the width of the radiation fins 32, as shown in FIGS. Therefore, the size of the second opening 41 of the fin cover 33 in the width direction X is the same as the width L2 of the heat radiating fins 32 (see FIG. 13). That is, the side portion 331 of the fin cover 33 is arranged along the side portion in the width direction X of the radiating fins 32 . As a result, it is possible to prevent the cooling air from passing through a space of the heat radiating fins 32 away from the heat radiating member 32a. Assuming that the second opening 41 has the same opening area as the first opening 40, in that case, the side surface of the radiation fin 32 in the width direction X and the side surface 331 of the fin cover 33 There will be a space between In that case, part of the cooling air passes through the space of the heat radiating fins 32 away from the heat radiating member 32a. In that case, the heat exchange efficiency between the cooling air and the heat radiating member 32a is lowered. Therefore, in the first embodiment, the second opening of the fin cover 33 is arranged to prevent a space from being formed between the side surface of the heat radiating fin 32 in the width direction X and the side surface 331 of the fin cover 33. 41 are formed in accordance with the width of the radiation fins 32 . As a result, it is possible to prevent the cooling air from passing through a space away from the heat radiating member 32a of the heat radiating fins 32 inside the fin cover 33. can be guessed.

Thus, in Embodiment 1, the fin cover 33 is provided to cover the radiation fins 32 . The fin cover 33 has a first opening 40 through which the cooling air taken in from the cooling fan 21 is taken into the heat radiating fins 32, and a first opening 40 through which the cooling air taken in from the first opening 40 cools the heat radiating fins 32 and then is discharged. 2 openings 41; In this way, the fin cover 33 covering the heat radiating fins 32 has the first opening 40 and the second opening 41 , so that the cooling air flows between the first opening 40 and the second opening 41 . A flowing air path is formed. As a result, the airflow of the cooling air discharged from the cooling fan 21 flows along the heat radiating members 32a of the heat radiating fins 32, so that the heat radiating members 32a of the heat radiating fins 32 can be efficiently exposed to the cooling air. Thereby, the heat dissipation performance of the power supply substrate 20 can be further improved.

FIG. 23 is an explanatory diagram showing the size relationship between the size in the width direction and the size in the height direction of the heat radiation fins in the rice cooker according to Embodiment 1. FIG. As shown in FIG. 23, the radiation fins 32 have a rectangular shape when viewed from the front. At this time, the size of the heat radiating fins 32 in the width direction X is defined as the width L2, and the size of the heat radiating fins 32 in the height direction Z is defined as the height H1. As shown in FIG. 23, the height H1 of the radiation fins 32 is greater than the width L2 of the radiation fins 32. As shown in FIG. Most of the heat of the power supply board 20 is dissipated by heat exchange between the heat dissipating member 32a of the heat dissipating fins 32 and the cooling air. Also, the cooling air flows along the height direction Z. As shown in FIG. Therefore, by increasing the height H1 of the heat radiating fins 32, the heat exchanging surface where heat is exchanged between the heat radiating member 32a of the heat radiating fins 32 and the cooling air is lengthened, thereby improving the heat exchange efficiency.

Next, the direction in which the cooling air flows will be described with reference to FIGS. 24 and 25. FIG. FIG. 24 is a diagram in which arrows indicating the direction of cooling air flow are added to FIG. FIG. 25 is a diagram in which arrows indicating the direction of cooling air flow are added to FIG.

As shown in FIG. 24, more than half of the cooling air generated by driving the cooling fan 21 flows into the fin cover 33, and the remaining cooling air flows to the induction heating coil 3 side. The cooling air that has flowed into the fin cover 33 rises inside the radiating fins 32 while cooling the heat radiating member 32a of the fin cover 32, as indicated by arrow B in FIG. It is discharged into the power supply substrate 20 through the opening 41 . Then, it flows through the power supply board 20 while cooling the components 205 (see FIG. 25) mounted on the power supply board 20 and flows from the lower opening of the power supply board 20 toward the central portion of the bottom case 8 . After that, the cooling air is discharged to the outside of rice cooker 100 through exhaust port 31 formed in bottom case 8 .

On the other hand, as indicated by arrows C1 and C2 in FIG. 24, the cooling air that has flowed toward the induction heating coil 3 has a "part" that flows upward, and the "other part" that flows horizontally. As indicated by arrow C1, the "portion" that flows upward rises with the space between inner case 2 and back surface portion 204 of power supply board 20 as an air path, and hits inner lid 7b. After that, the cooling air flows into the gap between the main body 1 and the inner case 2 of the rice cooker 100 . The cooling air is discharged to the outside of the rice cooker 100 from the exhaust port 31 formed in the bottom case 8 while absorbing heat from the induction heating coil 3 entering the gap. 24, the cooling air flowing in the "other portion" in the horizontal direction is directed to the space between the bottom surface of the inner case 2 and the bottom case 8 and the bottom surface of the inner case 2, as indicated by the arrow C2 in FIG. flow around. The cooling air is discharged to the outside of the rice cooker 100 from the exhaust port 31 formed in the bottom case 8 while cooling the induction heating coil 3 and the cord reel 22 .

In FIG. 25, arrows indicate the direction in which the cooling air flows in the power supply board 20 described with reference to FIG. The cooling fan 21 is driven to generate cooling air directed upward Z1. The cooling air directed upward Z1 flows toward the heat dissipation member 32a (see FIGS. 11 and 12) of the heat dissipation fins 32, as indicated by the outline arrow B in FIG. As a result, the cooling air passes through the heat radiating fins 32, thereby cooling the heat radiating members 32a of the heat radiating fins 32. As shown in FIG. The cooling air that has flowed in the upward direction Z1 inside the heat radiating fins 32 is discharged inside the power supply board 20 through the second openings 41 (see FIG. 22) of the fin cover 33 . Then, as indicated by an arrow D in FIG. 25, it hits the upper surface portion 202 of the power supply substrate 20 and develops toward the left side surface portion 203 and the right side surface portion 203 of the power supply substrate 20 . After that, the cooling air flows through the power supply board 20 in the downward direction Z2. The cooling air that has flowed downward Z2 flows into the central portion of the bottom case 8 of the rice cooker 100 through the gap at the bottom of the power supply board 20 . The cooling air flowing toward the central portion of the bottom case 8 flows toward the induction heating coil 3 provided in the inner pot 5 and cools the induction heating coil 3 . After that, the rice is discharged to the outside of the rice cooker 100 through the exhaust port 31 formed in the bottom case 8 .

Next, cooling air flowing along the fin cover 33 will be described with reference to FIG. FIG. 26 is a diagram in which arrows indicating the direction of cooling air flow are added to FIG. 20 . Although the fin cover 33 is not shown in FIG. 25 for explanation, the fin cover 33 is attached to the radiation fins 32 . Therefore, the cooling air flows along the fin covers 33 .

First, how the cooling air flows inside the fin cover 33 will be described. As described above with reference to FIG. 22, the opening area R1 of the first opening 40 of the fin cover 33 is larger than the opening area R2 of the second opening 41 . A tapered portion 332 is provided at the lower end portion of the side portion 331 of the fin cover 33 . Therefore, as indicated by arrow B in FIG. 26 , the cooling air drawn into the power supply board 20 by the cooling fan 21 flows along the inner wall of the tapered portion 332 of the fin cover 33 . At this time, the cooling air path is gradually narrowed by the inner wall of the tapered portion 332 of the fin cover 33 toward the upward direction Z1. This increases the flow velocity of the cooling air. In this manner, the taper portion 332 of the fin cover 33 increases the flow velocity of the cooling air, so that the cooling air can efficiently hit the radiating fins 32 . By providing the tapered portion 332 in this way, the flow velocity of the cooling air flowing through the power supply substrate 20 can be increased, thereby improving the cooling efficiency.

Next, how the cooling air flows outside the fin cover 33 will be described. As indicated by arrow D in FIG. 26 , the cooling air flowing out from the second opening 41 at the upper end of the fin cover 33 flows along the outer wall of the side surface 331 of the fin cover 33 . After that, the cooling air flows along the outer wall of the tapered portion 332 of the fin cover 33 . The tapered portions 332 widen in directions away from each other as they go downward in the height direction Z2. In this manner, the cooling air flows along the outer wall of the tapered portion 332, so that the cooling air spreads to the left and right as shown in FIG. As a result, the cooling air tends to flow toward the central portion of the bottom case 8 of the rice cooker 100 from the gap at the bottom of the power supply board 20 . The cooling air flowing toward the central portion of bottom case 8 is discharged to the outside of rice cooker 100 through exhaust port 31 formed in bottom case 8 . By providing the tapered portion 332 in this manner, the cooling air flowing outside the fin cover 33 can be guided, thereby improving the cooling efficiency.

Next, a method of arranging cooling fan 21 in rice cooker 100 according to Embodiment 1 will be described with reference to FIGS. 27 and 28. FIG. 27 is a cross-sectional view showing a method of arranging cooling fans provided in the rice cooker according to Embodiment 1. FIG. 28 is a partially enlarged view of FIG. 27. FIG.

In the first embodiment, as shown in FIGS. 27 and 28 , the cooling fan 21 is arranged such that the blowing direction E of the cooling air is closer to the power supply board 20 than the direction parallel to the power supply board surface portion 201 of the power supply board 20 . are arranged so as to incline in the direction of contact with the power supply board surface portion 201 of the .

As shown in FIG. 28, the cooling fan 21 is arranged such that the blowing direction E of the cooling air is tilted at an angle θ toward the power supply substrate surface portion 201 with respect to the direction parallel to the height direction Z. Specifically, the end portion 21a of the cooling fan 21 on the side of the power supply substrate surface portion 201 is arranged on the upward direction Z1 side of a plane passing through the central portion of the cooling fan 21 and parallel to the XY plane. In addition, the end 21b of the cooling fan 21 opposite to the power supply substrate surface 201 is arranged to be on the downward Z2 side of a plane passing through the central portion of the cooling fan 21 and parallel to the XY plane. Thus, as shown in FIG. 28, the cooling fan 21 is inclined so that the rear end 21a of the main body 1 is higher than the front end 21b. . Thus, the end portion 21a of the cooling fan 21 on the side of the power substrate surface portion 201 is arranged higher in the height direction Z than the end portion 21b of the cooling fan 21 on the side opposite to the power substrate surface portion 201 side. The ends 21a and 21b are both ends of the cooling fan 21 in the depth direction Y. As shown in FIG. The end portion 21a and the end portion 21b are arranged to face each other (see FIGS. 11 and 12).

According to Embodiment 1, as shown in FIG. 27 and FIG. Cooling air can be efficiently applied to the component 205 which is a heating element. As a result, the cooling performance of the power supply board 20 in the rice cooker 100 can be improved.

<Modification 1>
Next, Modification 1 of Embodiment 1 will be described with reference to FIGS. 29 to 32. FIG. 29 is a perspective view showing a configuration of a fin cover provided in the rice cooker according to Modification 1 of Embodiment 1. FIG. 30 is a perspective view showing a state where the fin cover is mounted on the power supply board in the rice cooker according to Modification 1 of Embodiment 1. FIG. 31 and 32 are plan views showing the configuration of the fin cover provided in the rice cooker according to Modification 1 of Embodiment 1. FIG. 31 shows the state of the fin cover viewed from the upper Z1 side of the height direction Z, and FIG. 32 shows the state of the fin cover viewed from the lower Z2 side of the height direction Z. As shown in FIG.

As shown in FIG. 29, in Modification 1, the inner surface of the fin cover 33A is provided with a convex portion 338 formed in a convex shape from the upper end portion 334 to the lower end portion 335 of the fin cover 33A. That is, the convex portion 338 is formed over the entire length in the height direction Z of the fin cover 33A.

As shown in FIGS. 29 to 32, the convex portion 338 is provided on the inner wall of the back surface portion 330 of the fin cover 33A. 31 and 32, the convex portion 338 protrudes from the inner wall of the back portion 330 in the front direction Y1 in the depth direction Y. As shown in FIG. The convex portion 338 protrudes from the inner wall of the back portion 330 toward the space 337 inside the fin cover 33A. When the fin cover 33A is attached to the heat radiating fins 32, the projections 338 are arranged parallel to the heat radiating members 32a of the heat radiating fins 32. As shown in FIG.

As shown in FIGS. 29 to 32, the convex portion 338 has a plate-like shape and is arranged in the center portion in the width direction X on the inner wall of the back portion 330 of the fin cover 33A. As described above, the heat dissipation fins 32 are attached to the power supply substrate 20 by the attachments 206 such as screws. Therefore, as shown in FIG. 31, in the central portion of the heat radiating fins 32 in the width direction X, in order to secure a space for arranging the mounting fixture 206, the interval W1 for arranging the heat radiating member 32a is set at the other portion. is larger than the interval W2. Since the gap W2 is narrow, the cooling air flowing through the gap of the gap W2 passes near the heat radiating member 32a of the heat radiating fins 32. As shown in FIG. Therefore, heat exchange between the heat radiating member 32a and the cooling air is efficiently performed. On the other hand, since the interval W1 is wider than the interval W2, part of the cooling air flowing through the gap of the interval W1 is separated from the heat radiating member 32a. In that case, the efficiency of heat exchange between the heat radiating member 32a and the cooling air is lowered. Therefore, in Modification 1, the convex portion 338 is arranged between the two heat radiating members 32a arranged at the interval W1. As a result, the cooling air flows through the narrow gap between the convex portion 338 and the heat radiating member 32a. As a result, the cooling air passes through the vicinity of the heat radiation member 32 a of the heat radiation fins 32 . Therefore, heat exchange between the heat radiating member 32a and the cooling air is efficiently performed.

Thus, in Modification 1, the protrusions 338 are provided in the region where the arrangement interval of the heat dissipation members 32a of the heat dissipation fins 32 is larger than that of the other heat dissipation members 32a. As a result, the cooling air flow path can be formed only in the vicinity of the heat radiating member 32a. As a result, the cooling air passes through the vicinity of the heat radiating member 32a of the heat radiating fins 32, so that heat is efficiently exchanged between the heat radiating member 32a and the cooling air, further improving the cooling performance.

In addition, although the convex part 338 may be formed over the full length in the depth direction Y of the fin cover 33A, in the modification 1, it is not the limitation. That is, in Modification 1, as shown in FIGS. 31 and 32, the convex portion 338 is formed to be shorter in the depth direction Y than the total length in the depth direction Y of the fin cover 33A. As described above, the heat dissipation fins 32 are attached to the power supply substrate 20 by the attachments 206 such as screws. Therefore, the convex portion 338 is formed to be shorter in the depth direction Y than the total length in the depth direction Y of the fin cover 33A so that the convex portion 338 does not come into contact with the fixture 206 .

Further, as shown in FIG. 29, the convex portion 338 has a V-shaped inclined portion 338a at the lower end portion. The inclined portion 338a is formed in a V shape protruding upwind in the direction in which the cooling air flows (that is, the direction toward the upward direction Z1). That is, when viewed from the front direction Y1 side of the depth direction Y, the inclined portion 338a has a V shape, that is, a triangular shape. The cross-sectional shape of the inclined portion 338a cut along a plane parallel to the XZ plane is triangular. The inclined portion 338a has the same rectangular shape as the convex portion 338 in plan view. That is, the inclined portion 338a is formed such that the plate thickness of the convex portion 338 gradually decreases in the downward direction Z2, and the tip portion (lower end portion) located on the windward side is sharp. That is, the inclined portion 338a is thinnest on the windward side, and gradually widens toward the leeward side.

Thus, the inclined portion 338a is provided to guide the cooling air discharged from the cooling fan 21. As shown in FIG. The cooling air discharged from the cooling fan 21 flows along the outer wall of the inclined portion 338 a and flows into the heat radiation fins 32 . Therefore, the airflow of the cooling air discharged from the cooling fan 21 is naturally guided to the radiating fins 32 without pressure loss.

If the inclined portion 338 a were not provided, the cooling air discharged from the cooling fan 21 would collide with the rectangular lower end portion of the convex portion 338 . In this case, the airflow of the cooling air discharged from the cooling fan 21 suffers pressure loss and the flow velocity decreases, and part of the cooling air flows toward the left and right of the convex portion 338, so that the heat radiation fins can be efficiently used. 32 is not guided.

In Modification 1, since the V-shaped inclined portion 338a is provided at the lower end portion of the convex portion 338, the cooling air discharged from the cooling fan 21 is guided to the radiating fins 32 without pressure loss. Thereby, the cooling air can be applied to the heat radiating fins 32 efficiently. As a result, the cooling performance is further improved.

As described above, in the rice cooker 100 according to Embodiment 1, the width L1 of the cooling fan 21 in the width direction X is larger than the width L2 of the radiation fins 32, as shown in FIG. By using the large-diameter cooling fan 21 in this way, the air volume of the cooling fan 21 is increased, and the heat radiation performance and cooling performance of the power supply board 20 are improved. As a result, even if the heating power of the rice cooker 100 is increased and the amount of heat generated by the power supply board 20 increases, the heat generated by the power supply board 20 can be efficiently dissipated, so that the temperature rise of the power supply board 20 can be suppressed. can be done. Therefore, the heating power of the rice cooker 100 can be increased compared to the conventional one. Therefore, in the rice cooker 100 according to Embodiment 1, the heating power of the rice cooker 100 can be improved by increasing the heating amount of the induction heating coil 3 . As a result, the rice can be cooked at a high temperature, so that the cooked rice has a better taste and can be cooked at a high speed.

Moreover, in the rice cooker 100 according to Embodiment 1, a fin cover 33 that covers the radiation fins 32 is provided. The fin cover 33 has a first opening 40 for introducing cooling air into the heat radiation fins 32 and a second opening 41 for discharging the cooling air after cooling the heat radiation fins 32 into the power supply board 20 . . As a result, the airflow emitted from the cooling fan 21 flows along the radiation fins 32 , so that the cooling air can efficiently hit the radiation fins 32 . As a result, the heat radiation performance and cooling performance of the power supply board 20 are improved.

Also, the opening area of the second opening 41 is formed to be smaller than the opening area of the first opening 40 . Therefore, the cooling air flowing through the inside of the fin cover 33 has a narrower air path as it goes downwind, so the air velocity gradually increases. By increasing the air velocity in this way, the cooling air can be efficiently applied to the heat radiating fins 32 . Also, the cooling air flowing outside the fin cover 33 flows along the outer wall of the tapered portion 332 of the fin cover 33 . The tapered portions 332 widen in directions away from each other as they go downward in the height direction Z2. In this manner, the cooling air flows along the outer wall of the tapered portion 332, so that the cooling air spreads to the left and right as shown in FIG. As a result, the cooling air tends to flow toward the central portion of the bottom case 8 of the rice cooker 100 from the gap at the bottom of the power supply board 20 . For these reasons, the heat radiation performance and cooling performance of the power supply board 20 are further improved.

1 Main Body 2 Inner Case 3 Induction Heating Coil 4 Temperature Sensor 5 Inner Pot 6 Hinge Part 7 Lid Body 7a Outer Lid 7b Inner Lid 8 Bottom Case 9 Lid Heater 20 Power Board 21 Cooling fan, 21a end, 21b end, 22 cord reel, 23 power plug, 24 operation display unit, 25 operation board, 30 intake port, 31 exhaust port, 32 heat dissipation fin, 32a heat dissipation member, 32b base, 33 fin cover, 33A Fin cover 40 First opening 41 Second opening 50 Flange 50a Horizontal part 50b Vertical part 100 Rice cooker 200 Rear member 201 Power board surface 202 Top surface 203 Side surface 204 Rear portion 205 Part 206 Fixture 330 Rear portion 330a Lower end region 331 Side portion 332 Taper portion 334 Upper end portion 335 Lower end portion 336 Protruding portion 337 Space 338 Protruding portion 338a Inclined portion B Arrow C1 Arrow C2 Arrow D Arrow E Blowing direction H1 Height L1 Width L2 Width R1 Opening area R2 Opening area X Width direction Y Depth direction Y1 Front direction Y2 Back direction Z Height direction, Z1 upward direction, Z2 downward direction, W1 interval, W2 interval, θ angle.

Claims (13)

a main body having a cylindrical shape with an upper end and a lower end opened;
a bottom case covering the opening at the lower end of the main body and having an intake port and an exhaust port;
an inner pot detachably housed inside the main body;
a heating unit arranged in the main body for heating the inner pot;
a power supply board arranged in the main body and driving the heating unit;
heat dissipation fins arranged on the power supply substrate;
a cooling fan disposed at the air inlet of the bottom case, for blowing cooling air taken in from the air inlet toward the heat radiating fins and the power supply substrate;
with
When the width direction of the main body is defined as a first direction,
The heat radiation fin has a plurality of heat radiation members arranged side by side at intervals in the first direction,
The width of the cooling fan in the first direction is greater than the width of the heat radiation fins in the first direction,
rice cooker. A fin cover that covers the heat radiation fins,
The fin cover is
a first opening that takes in the cooling air taken in from the air inlet by the cooling fan into the heat radiation fins;
a second opening for discharging the cooling air from the heat radiating fins after the cooling air taken in from the first opening cools the heat radiating fins;
having
The rice cooker according to claim 1. The opening area of the second opening is smaller than the opening area of the first opening,
The rice cooker according to claim 2. The first opening is formed to cover the cooling fan along the width of the cooling fan.
The rice cooker according to claim 2 or 3. The second opening is formed along the width of the radiation fin,
The rice cooker according to any one of claims 2-4. The fin cover has a box shape with at least a portion open,
When the height direction of the main body is the second direction,
The fin cover is
a pair of side portions extending in the second direction and arranged to face each other;
a pair of tapered portions provided at lower end portions of the side portions and widening in a direction away from each other in the downward direction in the second direction;
having
The rice cooker according to any one of claims 2-5. The cooling air taken into the heat radiating fins from the first opening of the fin cover flows along the inner wall of the tapered portion inside the fin cover,
The rice cooker according to claim 6. The cooling air discharged from the second opening of the fin cover toward the power supply board flows along the outer wall of the taper portion outside the fin cover and is guided by the outer wall of the taper portion. discharged from the exhaust port of the bottom case,
The rice cooker according to claim 6 or 7. The fin cover is provided on the inner surface of the fin cover and has a convex portion formed in a convex shape from the upper end portion to the lower end portion of the fin cover,
The rice cooker according to any one of claims 2-8. The convex portion has an inclined portion provided at a lower end portion of the convex portion,
The inclined portion is formed in a V shape protruding upwind in the direction in which the cooling air flows, and guides the cooling air taken in from the first opening to the heat radiating fins.
The rice cooker according to claim 9. The cooling fan is arranged such that the blowing direction of the cooling air is tilted in a direction in which the cooling air hits the mounting surface of the power supply board with respect to a direction parallel to the mounting surface on which the components are mounted of the power supply board. ing,
The rice cooker according to any one of claims 1-10. The power supply board has a box shape with at least a portion open,
The heat radiation fins are arranged in a central portion of a mounting surface forming a portion of the box-shaped shape of the power supply substrate,
The cooling air that has passed through the inside of the heat radiation fins is discharged from the heat radiation fins into the inside of the power supply board, cools the components mounted on the power supply board, and passes through the openings of the power supply board to the outside of the power supply board. discharged to the
The rice cooker according to any one of claims 1-11. When the depth direction of the main body is the third direction,
The power supply board and the air inlet are arranged on the back side in the third direction,
The exhaust port is arranged on the front side in the third direction,
The rice cooker according to any one of claims 1-12.

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