JP7291016B2 - rice cooker - Google Patents

Description

The present invention relates to a rice cooker.

Conventionally, a rice cooker equipped with a plurality of IH (Induction Heating) coils is known (see Patent Documents 1 and 2, for example). This type of rice cooker is provided with a temperature sensor that detects the temperature of the pot, and various substrates that control power supply to the IH coil based on the detected temperature.

However, in the conventional rice cooker, the temperature sensor and the layout of the board are not sufficiently considered.

JP-A-5-317172 JP-A-5-253058

An object of the present invention is to provide a rice cooker in which a temperature sensor and a substrate can be appropriately laid out.

As a means for solving the above-mentioned problems, the present invention provides a bottomed cylindrical pot housing portion for housing a pot, a rice cooker main body having a rice cooker main body outer shell, and a rice cooker main body arranged on the bottom side of the pot housing portion. a coil for induction-heating the pot; a substrate arranged in a front space formed between the outer shell of the rice cooker main body and the pot housing portion; a temperature sensor that abuts on the pot and the other end of which is arranged in a lateral space of the arrangement area of the substrate.

With this configuration, the substrates and the temperature sensors can be appropriately distributed on both sides of the front space, and the empty space in the front space can be effectively used.

A fan for taking in air from the outside of the rice cooker body shell and a first substrate on which a heat-generating component is mounted are provided in the rear space formed between the rice cooker body shell and the pot accommodating portion. It is preferable that a second substrate on which a non-heat generating component is mounted is arranged in the front space.

With this configuration, the air blown by the fan can be directly supplied to the first substrate, which is arranged in the rear space and on which the heat-generating components are mounted, to effectively cool the first substrate. By arranging the second substrate, which does not require much cooling by blowing air, in the front space, it is possible to effectively utilize the empty space in the main body of the rice cooker.

A pair of the coils are arranged in each region obtained by dividing the bottom side of the pot housing portion into two, and a passage for supplying air from the fan to the front space is provided between the pair of coils. is preferably formed.

With this configuration, it is possible to supply air to the second substrate arranged in the front space as well, thereby enhancing the cooling effect.

It is preferable that a third substrate on which a heat generating component is mounted is arranged in the front space.

With this configuration, the third substrate that cannot be arranged in the rear space can be separated and arranged in the front space, so that the empty space in the front space can be effectively used. Even if the third board is arranged in the front space, the air can be supplied from the fan through the passage, so that the board can be sufficiently cooled.

It is preferable that the third substrate is arranged closer to the passage than the second substrate.

This configuration makes it easier to cool the third substrate.

It is preferable to provide a first channel for blowing air from the fan directly to the first substrate and a second channel for blowing air to the passage.

With this configuration, the air from the fan is directly blown through the first flow path to the first board on which the heat-generating component is mounted to effectively cool it, while the air is arranged in the front space from the second flow path through the passage. The second substrate or the third substrate can also be cooled.

It is preferable that a substrate space in which the third substrate is arranged is formed in the front space, and an air inlet portion of the substrate space opens toward the passage side.

With this configuration, the air guided to the front space through the passage can smoothly flow into the substrate space, and the third substrate can be effectively cooled. Also, the third board itself is protected by being arranged in the board space, and there is no risk of damage during assembly work or the like.

According to the present invention, the temperature sensor and the substrate can be appropriately laid out by effectively utilizing the empty space in the front space.

1 is a perspective view of a rice cooker according to this embodiment; FIG. Fig. 2 is an exploded perspective view of the rice cooker shown in Fig. 1 with the lid removed and the pot and the outer shell of the rice cooker main body removed; 2 is a perspective view of the rice cooker main body shown in FIG. 1 as viewed from below; FIG. 2 is an exploded perspective view of the main body of the rice cooker shown in FIG. 1; FIG. FIG. 5 is a perspective view of a protective frame shown in FIG. 4; FIG. 5 is a perspective view of the protective frame shown in FIG. 4 and parts attached to the protective frame as viewed from the bottom side; FIG. 7 is an exploded perspective view showing a state in which some parts are removed from the protective frame shown in FIG. 6; Fig. 2 is a plan sectional view of the rice cooker shown in Fig. 1; It is a schematic diagram of the side cross section of the rice cooker shown in FIG. 2 is a block diagram showing electrical wiring of the rice cooker shown in FIG. 1; FIG.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a perspective view of a rice cooker according to this embodiment. In the following description, in FIG. 1, the direction diagonally downward to the left is "front", the direction diagonally upward to the right is "rear", the direction diagonally upward to the left is "left", and the direction diagonally downward to the right is " "right", the upward direction as "top", and the downward direction as "bottom".

Also referring to FIG. 2, the rice cooker includes a rice cooker body 1, a lid body 2 rotatably supported by a hinge portion 41 of the rice cooker body, and a pan 3 housed therein. A rice cooking switch 4, a display section 5, and the like are exposed on the upper surface of the lid 2. As shown in FIG. Also referring to FIG. 3 , the rice cooker main body 1 includes a rice cooker main body outer shell 1 a and a pot accommodating portion 8 in which the pot 3 is accommodated. The outer shell 1a of the rice cooker main body has a box-like shape which is substantially rectangular in plan view, and has an air intake port 6 formed in the rear portion of the bottom surface and a lower portion of the rear surface, and an exhaust port 7 formed in the front portion of the bottom surface. . As shown in FIG. 4 , the pot housing portion 8 has a protective frame 9 , an inner body 10 and shoulder members 11 .

Referring also to FIG. 5 , the protective frame 9 is made of a non-magnetic material such as a synthetic resin material and has a bottomed cylindrical shape, and includes a hollow cylindrical cylindrical portion 12 and a dish-shaped bottom portion 13 .

A substrate mounting portion 14 is formed on the front side of the protective frame 9 . The substrate mounting portion 14 has a rectangular plate-like shape, with an upper end protruding above the cylindrical portion 12 and a lower end protruding below the bottom portion 13 . A first mounting portion 15 and a second mounting portion 16 adjacent to the lower side thereof are provided on the outer surface side of the substrate mounting portion 14 . A first guide wall 17 projecting forward is formed on the upper edge and left and right edges of the first mounting portion 15 . A power supply board 18 corresponding to the second board of the present invention is arranged along the first guide wall 17 on the first mounting portion 15 and fixed by screwing. The second mounting portion 16 and the first mounting portion 15 are separated by a second guide wall 19 . However, the second guide wall 19 is not formed at the lower end of the second attachment portion 16 . A terminal block substrate 20 corresponding to the third substrate of the present invention is arranged along the second guide wall 19 on the second mounting portion 16 and fixed with screws. A lower end portion of the terminal board 20 protrudes downward from the board mounting portion 14 . A board cover 21 is attached to the board mounting portion 14 to cover the power supply board 18 and the terminal block board 20 . The upper end portion and left and right side portions of the board cover 21 abut against the first guide wall 17 and form a gap with the second guide wall 19 . As shown in FIG. 9 , the lower end of the board cover 21 is bent toward the board mounting portion 14 and positioned below the lower end of the terminal block board 20 . An air inflow portion 14 a is formed by the substrate mounting portion 14 and the lower end portion of the substrate cover 21 . The air inflow portion 14 a facilitates the flow of air from a later-described passage 38 into the board space 14 b defined by the board mounting portion 14 and the board cover 21 . In the board space 14b, the terminal block board 20 on which the heat-generating component is mounted is arranged on the side of the air inlet portion 14a, and the power supply board 18 is arranged on the far side. Therefore, the terminal board 20 can be preferentially cooled. Further, notch portions 21a are formed on both left and right sides of the board cover 21 so that the air that has flowed into the board space 14b can flow out.

As shown in FIG. 8, a cylindrical insertion portion 22 is formed in the vicinity of the side of the board mounting portion 14 . The position where the insertion portion 22 is formed is a straight line obtained by rotating a straight line (first center line CL1) that divides the protective frame 9 into left and right sides when viewed from the bottom side by a predetermined angle (for example, 30°) counterclockwise. It is on (the second center line CL2). A side sensor 23 (see FIG. 5), which is an example of the temperature sensor of the present invention, is attached to the insertion portion 22 . The side sensor 23 is composed of a sensor portion 23a and a holder portion 23b. The sensor portion 23a is biased in the protruding direction by a spring (not shown) provided inside the holder portion 23b. When the side sensor 23 is attached to the insertion portion 22 , the sensor portion 23 a protrudes into the pot housing portion 8 and can be press-contacted with the pot 3 . The front wall of the rice cooker main body outer shell 1a is formed in a straight line, and the front portion of the protective frame 9 is formed in an arc shape. For this reason, the front space formed between the front wall of the outer shell 1a of the rice cooker main body and the front portion of the protective frame 9 has the smallest gap in the left-right direction at the first center line CL1 and widens toward the left and right sides. It's becoming Therefore, the power supply board 18 and the terminal block board 20 are arranged from the left part to the right part of the first center line CL1 part, and the side sensor 23 is arranged in the remaining part on the right side. In other words, the side sensor 23 can be arranged on the right side by arranging the power supply board 18 and the terminal block board 20 with their positions shifted to the left side. As a result, it becomes possible to effectively utilize the empty space in the front space.

Returning to FIG. 4 , a substrate holder 24 is attached to the rear side of the protective frame 9 . The substrate holder 24 has both side walls 24a connected by a connecting wall 24b. Mounting pieces 24c extending obliquely downward toward the front are formed on both sides of the connecting wall 24b. An IH substrate 25 and a resonance substrate 26 corresponding to the first substrate of the present invention are screwed and fixed to bosses 24d (one of which is not shown) projecting from the connecting wall 24b. Heat-generating components such as IGBTs and diode bridges are mounted on the IH board 25, and heat-generating components such as a resonance capacitor are mounted on the resonance board 26, respectively. A rear space BS formed between the rear wall of the rice cooker main body outer shell 1a and the rear portion of the protective frame 9 is divided into two parts in the front-rear direction by the IH board 25 . A fan 27 is attached between the pair of attachment pieces 24c. By driving the fan 27, ambient air is sucked through the intake port 6 formed on the rear side of the bottom surface of the rice cooker main body outer shell 1a and sent to each of the rear spaces BS divided by the IH board 25. As shown in FIG. 9, the rear area of the rear space BS is the first flow path P1 that blows the air from the fan 27 directly to the IH substrate. A front area of the rear space BS is the second flow path P2 that guides the air from the fan 27 to the substrate space of the front space FS through the passage 38 . Here, the cross-sectional area of the first flow path P1 is set larger than that of the second flow path P2. This is because most of the boards on which heat-generating components are mounted are arranged in the rear space BS, so that these boards are effectively cooled. The IH board 25 is formed together with the terminal block board 20 by mounting various electronic components on a single board, soldering it in a solder bath, and then cutting it. As shown in FIG. 8, a cord reel 29 that automatically winds a cord having a power plug 28 is arranged on the side of the substrate holder 24 . Like the front space FS, the rear space BS is narrow at the first center line CL1 portion and wide on both the left and right sides. Therefore, the cord reel 29 is arranged on the left side of the rear space BS, and the IH board 25 is arranged from the right part to part of the left part of the first center line CL1. The terminal block substrate 20 is arranged inside the IH substrate 25 at the portion where the space on the right side of the rear space BS is widened. In other words, by arranging the terminal board 20 and the cord reel 29 in the portions wider than the central portion on both the left and right sides, the empty space of the rear space BS is effectively utilized.

As shown in FIG. 5, the upper opening of the protective frame 9 has a stepped shape, and recesses 30 are formed at three locations on the stepped portion. A rubber piece (not shown) is attached to each recess 30 . The rubber piece is pressed against the outer peripheral surface of the pan 3 accommodated in the pan accommodating portion 8 to stabilize the accommodated state of the pan 3. - 特許庁

As shown in FIG. 7, two sets of coils 31, ferrite holders 32, and reflectors 33 are attached to the bottom surface of the protective frame 9. As shown in FIG. These are arranged in respective regions divided into two around a second center line CL2 passing through the center of the bottom portion 13 of the protective frame 9 and the center of the insertion portion 22 in which the side sensor 23 is arranged (Fig. 6).

The coil 31 is wound in an annular shape and has a substantially elliptical shape in a plan view. Each coil 31 includes a linear portion 31a along the second center line CL2 of the bottom portion 13 and an arc portion 31b along the curved portion on the outer diameter side of the bottom portion 13 . Lead wires (not shown) are connected to both ends of each coil 31 . The lead wires are passed through an insulating tube (not shown). Each coil 31 is arranged on the bottom surface of the protective frame 9 and guided on the inner diameter side by a plurality of bosses 9 a protruding from the bottom surface of the protective frame 9 . Each coil 31 is arranged in respective regions on both sides of a second center line CL2 rotated by a predetermined angle (for example, 30°) in a clockwise direction when viewed from the bottom side with respect to the first center line CL1. ing. A gap is formed between the linear portions 31a of the coils 31. As shown in FIG.

The ferrite holder 32 comprises a fan-shaped flat portion 32a, and an arm portion 32b and an extension piece 32c obliquely extending therefrom. The flat portion 32a covers the linear portion 31a of the coil 31 and the inner portion of the arcuate portion 31b, and the arm portion 32b and the extension piece 32c cover part of the arcuate portion 31b of the coil 31, respectively. Ferrite support portions 34 are formed at three locations on the upper surface of the planar portion 32a. A ferrite support portion 34 is also formed on the arm portion 32b. Each ferrite support portion 34 supports a rod-shaped ferrite 35 (only one is shown in FIG. 4) having a rectangular cross section. The ferrite 35 has high magnetic permeability and converges the magnetic flux generated by energizing the coil 31 . As a result, the leakage magnetic flux is suppressed, the magnetic flux is concentrated in the pot 3, and the pot 3 is effectively heated. A fuse support portion 36 extending obliquely is formed between the center of the plane portion 32a and the ferrite support portion 34 on one side. A thermal fuse 37 (only one is shown in FIG. 7) is elastically supported by the fuse support portion 36 . The ferrite holder 32 is fixed to the boss 9a of the protective frame 9 by screwing. The ferrite holder 32 positions the coil 31 by having its bottom surface along the surface of the coil 31 while being fixed to the protective frame 9 .

The reflector 33 has substantially the same shape as the ferrite holder 32 and is arranged in contact with the lower surface of the ferrite holder 32 . The reflector 33 is made of a material such as copper, aluminum, or the like, which has an electrical resistance smaller than that of the pot 3 . The reflector 33 prevents the high-frequency magnetic field generated by energizing the coil 31 from adversely affecting peripheral devices.

As shown in FIG. 6, a passage 38 is formed between the coil 31, the ferrite holder 32 and the reflector 33. As shown in FIG. The passageway 38 extends along a second centerline CL2 inclined with respect to the first centerline CL1. A lead wire connected to each coil 31 is arranged in the passage 38 while being covered with an insulating tube. Each lead extends rearward and is electrically connected to the IH substrate 25 . By forming the passage 38, the air taken into the rear space BS from the outside by the driving of the fan 27 can flow to the front space FS.

Returning to FIG. 4 , the inner barrel 10 is made of a cylindrical metal material and is attached to a step formed in the upper opening of the protective frame 9 . The inner barrel 10 has an inner diameter slightly larger than that of the pot 3 and is sandwiched between the protective frame 9 and the shoulder member 11. - 特許庁

The shoulder member 11 is made of a synthetic resin material and attached to the upper opening of the outer shell 1a of the rice cooker main body. A plurality of bosses (not shown) protrude from the lower surface of the shoulder member 11, and a barrel reinforcing plate 39 arranged between the inner barrel 10 and the rice cooker main body outer shell 1a is screwed and fixed. The trunk reinforcing plate 39 is formed with an opening cylindrical portion 39a having the same inner diameter as that of the inner trunk 10 . Inner body spacers 40 are attached to recesses 30 formed at five locations at the lower end of the open cylindrical portion 39a. The inner body spacer 40 abuts on the outer peripheral surface of the pot 3 accommodated in the pot accommodating portion 8 to position the pot 3 .

A hinge portion 41 is provided behind the shoulder member 11 . The hinge portion 41 is composed of a hinge fitting 42 , a hinge reinforcing plate 43 and a hinge cover 44 . The hinge fitting 42 and the hinge reinforcing plate 43 are screwed and fixed to the trunk reinforcing plate 39 . The hinge cover 44 is screwed to the shoulder member 11 and covers the hinge fitting 42 and the hinge reinforcing plate 43 . A battery substrate 45 is attached to the hinge cover 44 . The hinge portion 41 rotatably supports the lid body 2 .

FIG. 10 is a block diagram showing electrical wiring of the rice cooker according to this embodiment. A cord reel 29 is electrically connected to the IH board 25, and power is supplied from a commercial power source. A power supply board 18 is electrically connected to the IH board 25 . The power supply board 18 drops the voltage (100V) of the power input from the IH board 25 (for example, 20V and 5V). The power voltage-dropped by the power supply board 18 is returned to the IH board 25 . The IH board 25 is electrically connected to the battery board 45 . Electric power with a voltage drop (to 20 V) is input to the battery substrate 45, and the fan 27 is driven based on this input electric power. A display substrate 46 provided on the lid 2 is electrically connected to the battery substrate 45 . The display board 46 performs the display of the display section 5 and the like by using the power that is input from the battery board 45 and has the voltage dropped (to 5 V). The IH substrate 25 is electrically connected to the resonance substrate 26 . The resonance board 26 is electrically connected to the terminal block board 20 . The terminal board 20 controls the energization of the two coils 31 based on the voltage-dropped power (to 20V).

The rice cooker configured as described above is, for example, a small-sized rice cooker capable of cooking 3 cups or 5.5 cups. In this rice cooker, the rice cooking process is started when the rice cooking switch 4 is operated. In the rice cooking process, high-frequency current is supplied from the IH board 25 to the coil 31 at the following timings controlled by the resonance board 26 to perform the rice cooking process. Here, only the energization of the coil 31 and the driving of the fan 27 will be described.

That is, only one coil 31 is energized with a high-frequency current, and the pot 3 is induction-heated in the half region on the bottom side corresponding to this coil 31 . As a result, half of the pot 3 becomes a heating area, and vertical convection occurs. Similarly, a high-frequency current is applied only to the other coil 31, and the pot 3 is induction-heated in the remaining half area on the bottom side corresponding to this coil. As a result, the remaining half of the pot 3 becomes a heating area, and vertical convection occurs.

By alternately energizing the two coils 31 in this manner, vertical convection occurs alternately in the half region of the pot 3, and the convection state can be complicated. Therefore, an excellent stirring effect can be obtained as compared with the case of heating with a single coil 31, and it is possible to bring out the umami components (such as eluted sugar) contained in cooked rice.

In addition, the fan 27 is appropriately driven to allow outside air to flow into the rear space BS from the intake port 6 . As shown in FIG. 9, part of the inflowing air flows through the rear area of the rear space BS, ie, the first flow path P1, and is directly blown onto the IH substrate 25 and the terminal block substrate 20, thereby removing heat-generating components such as IGBTs. Cooling effectively. After that, it flows forward along the outer surfaces of the inner barrel 10 and the protective frame 9 and is discharged to the outside through the exhaust port 7 .

The remainder of the inflowing air flows through the front area of the rear space BS, ie, the second flow path P2, and is guided to the front space FS via the passage 38. As shown in FIG. Although lead wires covered with an insulating tube are arranged in the passage 38, it is possible to sufficiently flow air.

In the front space FS, an air inlet portion 14a formed by the board mounting portion 14 and the board cover 21 is open. Therefore, the air that has flowed into the front space FS from the passage 38 smoothly flows into the substrate space 14b. In the board space 14b, a terminal block board 20 on which a heat-generating component is mounted is arranged on the side of the air inlet portion 14a. Therefore, the terminal board 20 can be effectively cooled. The air that has flowed into the board space 14b cools the power supply board 18 as well, and then is discharged to the outside from the exhaust port 7 through the notch.

According to the rice cooker according to the embodiment, the following effects can be obtained.
(1) The size of the front space FS is larger on the left and right sides than the central portion, but the side sensor 23, the power supply board 18, and the terminal block board 20 are arranged with their positions shifted left and right. . Therefore, the empty space in the front space FS can be effectively used to realize a lean layout. As a result, the rice cooker itself can be made compact.
(2) The size of the rear space BS is also larger on the left and right sides compared to the central portion, but the IH substrate 25, the resonance substrate 26 and the cord reel 29 are appropriately distributed to the left and right. Therefore, even the rear space BS can be made compact by effectively utilizing the empty space.
(3) The IH board 25 and the resonance board 26 on which heat-generating components are mounted are arranged in the rear space BS. Air taken in from the outside is directly supplied to these substrates by a fan 27 also arranged in the rear space BS. Therefore, the IH substrate 25 and the resonance substrate 26 can be effectively cooled.
(4) Between the pair of coils 31, a passage 38 is formed that extends linearly from the rear space BS to the front space FS. Therefore, the air from the fan 27 arranged in the rear space BS can be smoothly led to the terminal board 20 arranged in the front space FS to cool it.

The present invention is not limited to the configurations described in the above embodiments, and various modifications are possible.

In the above embodiment, the passage 38 is formed on the second center line CL2 rotated by a predetermined angle in the clockwise direction with respect to the first center line CL1. The arrangement may be symmetrical to that in FIG. In this case, the positions of the substrates, the side sensor 23, and the cord reel 29 are reversed left to right.

DESCRIPTION OF SYMBOLS 1... Rice cooker main body 1a... Rice cooker main body outer shell 2... Lid body 3... Pot 4... Rice cooking switch 5... Display part 6... Intake port 7... Exhaust port 8... Pot accommodating part 9... Protective frame 10... Inner body 11... Shoulder member 12 Cylindrical portion 13 Bottom portion 14 Substrate mounting portion 14a Air inflow portion 14b Substrate space 15 First mounting portion 16 Second mounting portion 17 First guide wall 18 Power supply substrate (second substrate)
19... Second guide wall 20... Terminal board (third board)
DESCRIPTION OF SYMBOLS 21... Substrate cover 22... Insertion part 23... Side sensor 24... Substrate holder 25... IH substrate (1st substrate)
26 Resonance substrate (first substrate)
27 Fan 28 Power supply plug 29 Cord reel 30 Recess 31 Coil 32 Ferrite holder 33 Reflector 34 Ferrite support 35 Ferrite 36 Fuse support 37 Thermal fuse 38 Passage 39 Body reinforcing plate DESCRIPTION OF SYMBOLS 40... Inner trunk|drum spacer 41... Hinge part 42... Hinge metal fitting 43... Hinge reinforcing plate 44... Hinge cover 45... Battery board 46... Display board

Claims (5)

A rice cooker main body having a bottomed cylindrical pot housing portion for housing a pot and a rice cooker main body outer shell;
a coil disposed on the bottom side of the pot housing portion for induction heating the pot;
a substrate arranged in a front space formed between the outer shell of the rice cooker main body and the pot accommodating portion;
a temperature sensor that is attached to the pan accommodating portion, has one end that abuts the pan, and the other end that is arranged laterally of the arrangement area of the substrate;
with
A fan for taking in air from the outside of the rice cooker main body shell and a first substrate on which a heat generating component is mounted are provided in the rear space formed between the rice cooker main body outer shell and the pot accommodating portion. is placed and
The substrate arranged in the front space includes a second substrate on which a non-heat generating component is mounted,
The coil is composed of a pair arranged in each region obtained by dividing the bottom side of the pot housing portion into two,
A rice cooker, wherein a passage is formed between the pair of coils so that air from the fan can be supplied to the front space. 2. The rice cooker according to claim 1 , wherein said substrate arranged in said front space includes a third substrate on which a heat generating component is mounted. The rice cooker according to claim 2 , wherein said third substrate is arranged closer to said passage than said second substrate. 4. The rice cooker according to any one of claims 1 to 3 , comprising: a first channel for blowing air from said fan directly to said first substrate; and a second channel for blowing air to said passage. . A substrate space in which the third substrate is arranged is formed in the front space,
The rice cooker according to claim 2 or 3 , wherein an air inlet portion of said substrate space opens toward said passage side.

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