JP7577052B2 - Rice cooker - Google Patents

Description

The present invention relates to a rice cooker with a structure that prevents sticky rice and other ingredients from boiling over.

It has been common practice in rice cookers to separate the steam and sticky rice generated in the inner pot during cooking, release the steam to the outside, and return the sticky rice to the inner pot. For example, Patent Document 1 discloses a rice cooker in which an inner lid is made up of an upper plate and a lower plate with a space between them, sticky rice steam in the inner pot is introduced into the space through a steam inlet hole in the lower plate, the sticky rice and steam are separated in this space, and the steam is discharged to the outside through a steam exhaust hole in the upper plate and a steam exhaust part in the outer lid, and the sticky rice that has accumulated in the recess of the space is returned to the inner pot when cooking is finished and the pressure in the inner pot drops, opening the opening and closing valve on the lower plate.

Patent No. 6448372

However, in the rice cooker described in Patent Document 1, when multiple inner lids are used to create a space to separate the sticky rice, it is necessary to connect the upper and lower plates with hinges, which increases the number of parts and makes the structure complicated.

This disclosure has been made to solve these problems, and aims to provide a rice cooker that has a simple inner lid configuration but can adequately separate steam and sticky rice, and can suppress a drop in temperature inside the inner pot caused by the influence of outside air.

The rice cooker disclosed herein is a rice cooker comprising a main body having an inner pot with an open top, a heating means for heating the inner pot and an inner pot storage section for housing the inner pot, and a lid connected to the main body by a hinge and covering the top of the main body. The lid comprises an outer lid covering the top of the main body, and an inner lid detachably attached to the bottom surface of the outer lid facing the main body and placed in a position covering the opening on the top of the inner pot. The outer lid has a steam path section with a concave shape formed on the main body side of the outer lid, and a steam exhaust port formed on the upper wall surface of the steam path section and on the rear side of the main body, forming an opening that communicates with the top surface of the lid. The inner lid has a sticky rice reservoir section with a concave shape and a bottom surface portion protruding toward the inner pot side, which is located opposite the steam path section, and a steam inlet port forming an opening that communicates with the inside of the inner pot. The sticky rice reservoir section is characterized by having a sticky rice return hole that forms an opening that communicates with the inside of the inner pot on the bottom surface at a position offset toward the center of the inner pot when viewed from above from the steam exhaust port.

The rice cooker disclosed herein is provided with a sticky rice return hole that forms an opening that communicates with the inside of the inner pot on the bottom surface at a position offset toward the center of the inner pot when viewed from above relative to the steam exhaust port, making it possible to obtain a rice cooker that can adequately recover sticky rice despite a simple inner lid configuration and can prevent the temperature drop of the heated items inside the inner pot caused by outside air.

1 is an external perspective view of the rice cooker of the first embodiment with the lid closed; FIG. 1 is an external perspective view of the rice cooker according to the first embodiment with the lid open; FIG. 1 is an external perspective view of the rice cooker according to the first embodiment with the inner lid removed; FIG. 1 is a schematic vertical cross-sectional view of a rice cooker according to a first embodiment. FIG. 1 is an external oblique view of the inner lid of the rice cooker according to the first embodiment, viewed from the bottom side. FIG. 4 is a bottom view of the inner lid of the rice cooker according to the first embodiment. FIG. 4 is a partially enlarged view of the underside of the inner lid of the rice cooker according to the first embodiment. FIG. A cross-sectional view of the inner lid of the rice cooker according to embodiment 1. 2 is a schematic vertical cross-sectional view of the steam path and its surroundings of the rice cooker according to the first embodiment. FIG. A diagram showing the flow of sticky rice and steam in the steam path of the rice cooker in embodiment 1. 1 shows the change in sticky foam passing through the steam inlet of the rice cooker of embodiment 1. 11 is a schematic vertical cross-sectional view of the steam path and its surroundings of a rice cooker according to a second embodiment. FIG. 11 is a schematic vertical cross-sectional view of the steam path and its surroundings of a rice cooker according to embodiment 3. FIG. 13 is a schematic vertical cross-sectional view of the steam passage and its surroundings of a rice cooker according to embodiment 3, showing the valve body in an open state. FIG. 13 is a schematic vertical cross-sectional view of the steam path and its surroundings of a rice cooker according to embodiment 4. FIG.

Below, an embodiment incorporating the technology of the present disclosure will be described with reference to the drawings. Note that the embodiment described below is only one example, and the invention is not limited to the configuration described in the embodiment. Also, the drawings below are only one example of a configuration incorporating the technology of the present disclosure, and the size relationships between the various components may differ from the actual ones.

Embodiment 1.
Fig. 1 is an external perspective view of the rice cooker with the lid closed. Fig. 2 is an external perspective view with the lid open. Fig. 3 is an external perspective view with the inner lid removed from Fig. 2. Fig. 4 is a schematic vertical cross-sectional view of the rice cooker. Fig. 5 is an external perspective view of the inner lid as seen from the bottom side. Fig. 6 is a bottom view of the inner lid. Fig. 7 is a partially enlarged view of the bottom surface of the inner lid. Fig. 8 is a vertical cross-sectional view of the inner lid. Fig. 9 is a schematic vertical cross-sectional view of the steam path and its surroundings.
For ease of explanation, the directions indicated by dotted arrows in FIG. 1 are the front and rear (dorsal) directions, the directions indicated by solid arrows are the right and left directions or lateral directions, and the directions indicated by thick arrows are the up and down directions.

As shown in Figures 1 to 4, the rice cooker 100 is mainly composed of a main body 1 and a lid 2.

The main body 1 is structured to store the inner pot 3 inside, and is provided with an inner pot storage section 11 that forms a storage space for storing the inner pot 3 inside. The main body 1 also has a heating coil 12 provided under the bottom surface of the inner pot storage section 11 and a body heater 13 provided on the side of the inner pot storage section 11 as heating means for induction heating the inner pot 3. The main body 1 also has a bottom thermistor 15 provided in the center of the bottom surface of the inner pot storage section 11 to detect the temperature of the inner pot 3, and a power supply board 17 provided at the rear inside the main body 1 and on which a circuit is mounted to supply power converted from a commercial power source to the heating coil 12 and the body heater 13 by converting it into high-frequency power. The front of the main body 1 is provided with a lid opening button 16 that is used when releasing the fixing of the support structure that fixes the lid body 2 in a state where the top surface of the main body 1 is closed.

The lid body 2 comprises an outer lid 20 that covers the entire top surface of the main body 1, and an inner lid 30 that is detachably attached to the underside of the outer lid 20 facing the main body 1. The outer lid 20 is rotatably connected to the rear of the main body 1, and has a support structure that allows the entire lid body 2 to be rotatably connected to the main body 1 and fixed to the main body 1 while covering the top surface of the main body 1. In addition, the inner lid 30 is installed in a position that covers the opening on the top surface of the inner pot 3 when the lid body 2 is fixed in a position that closes the top surface of the main body 1.

The inner pot 3 holds the food to be cooked, such as rice, and is cylindrical with a bottom. Specifically, the inner pot 3 is made up of a bottom 3a with a slightly upwardly convex central portion, a cylindrical outer periphery 3b that is continuous with the bottom 3a, and a stepped upper outer periphery 3c that spreads outward from the upper end of the outer periphery 3b, and is shaped so that the top side is open. The outer periphery 3b is structured so that the inner wall diameter of the cylinder is larger at the center than the bottom 3a side and the upper outer periphery 3c side. The upper outer periphery 3c is also structured so that the inner wall diameter of the cylinder is larger than the inner wall diameter of the outer periphery 3b. Specifically, the inner diameter Rb of a circle horizontally cutting the upper outer periphery 3c is 1.1Ra, which is the inner diameter Ra of a circle horizontally cutting the outer periphery 3b. In other words, when viewed from above, the inner pot 3 is structured so that the opening of the upper outer periphery 3c is larger than the upper side of the outer periphery 3b.

The heating coil 12 and the body heater 13 are heating means for induction heating the inner pot 3, and are each a coil formed in a circular ring shape. The heating coil 12 and the body heater 13 generate heat by receiving power from the power supply board 17, which is commercial power converted into high-frequency power, and heat the inner pot 3.

The bottom thermistor 15 is a temperature sensor that contacts the bottom surface of the inner pot 3. The bottom thermistor 15 transmits information about the detected temperature of the inner pot 3 to the power supply board 17 as a power signal.

When the user presses the lid-open button 16, the outer lid 20 is released from the main body 1. This allows the user to open the lid 2 and remove the inner pot 3 stored in the main body 1 or the rice inside the inner pot 3.

The power supply board 17 is composed of components such as switching elements that make up an inverter circuit, and generates high-frequency power supplied from a commercial power source to the heating coil 12 and the body heater 13. During the rice cooking process, the power supply board 17 also adjusts the amount of heat from the heating coil 12 and the body heater 13 so that the temperature of the inner pot 3 detected by the bottom thermistor 15 becomes a predetermined temperature, thereby controlling the amount of heat applied to the heated object in the inner pot 3. Specifically, the power supply board 17 controls the temperature of the inner pot 3 detected by the bottom thermistor 15 to maintain a predetermined temperature by adjusting the number of times and the interval at which the power supply to the heating coil 12 is switched on and off.

Next, the structure of the outer lid 20 will be explained in more detail.

The outer lid 20 has a connection part 26 on the rear side of the outer lid 20 to the main body 1, and the connection part 26 is rotatably connected to the hinge part 14 at the rear upper part of the main body 1. With this structure, the outer lid 20 rotatably connects the entire lid body 2 to the main body 1. As a result, the main body 1 can be fixed in a position where the lid body 2 covers the top surface of the main body 1, thereby improving the airtightness of the inner pot 3 inside. In addition, the main body 1 can be rotated to a position where the lid body 2 does not cover the top surface of the main body 1, allowing the inner pot 3 to be stored and the user to remove the rice from the inner pot 3.

The outer lid 20 has an operation panel 21 equipped with various operation buttons such as a rice cooking button on the front side of the upper surface thereof. In addition, an operation board 22 on which various input switches corresponding to the various operation buttons are mounted is provided inside the outer lid 20.
The operation board 22 outputs control signals based on inputs from various input switches to the power supply board 17. The circuits constituting the operation board 22 can be configured with hardware such as a circuit device that realizes the functions, or can be configured with a calculation device such as a CPU or a microcomputer and software that defines the operation of the circuit device.

In addition, a lid sensor 23 that detects the temperature inside the inner pot 3 is provided on the underside of the outer lid 20. The lid sensor 23 outputs a detected signal to the power supply board 17.

The outer lid 20 has a steam path 27 formed on the inner lower surface on the main body 1 side, which is a wall surface that is greatly recessed on the upper surface side of the outer lid 20 toward the rear of the rice cooker 100, where a connection part 26 that connects to the hinge part 14 is located from near the center of the inner pot 3 when viewed from above the rice cooker 100. The outer lid 20 is configured to form a large space between the inner lid 30 and the main body 1 side by this steam path 27. In addition, the steam path 27 forms a steam exhaust port 28, which is an opening that communicates with the outside of the rice cooker 100, on the upper wall surface of the steam path 27 and on the rear side of the main body 1. In other words, the steam exhaust port 28 is an opening that communicates between the large space formed between the steam path 27 and the inner lid 30 and the outside of the rice cooker 100.
In addition, the outer lid 20 has an inner lid release lever 24 on the front side of the inner side surface, and two support parts 25 spaced apart on the rear side of the inner side surface. The inner lid release lever 24 is released from the engagement of the inner lid 30 with the outer lid 20 by the user pushing in the lever.

Next, the inner lid 30 will be described in more detail using Figures 5 to 8 and 12.

The inner lid 30 is detachably attached to the underside of the outer lid 20 facing the main body 1. The inner lid 30 is positioned to close the upper opening of the inner pot 3 when the lid 2 is closed on the top of the main body 1. The inner lid 30 is mainly made of sheet metal, which is a disk-shaped plate material such as aluminum or stainless steel, and has a first protrusion 31 formed of a resin material and attached to the periphery of the sheet metal, and a second protrusion 32 provided in a position opposite the first protrusion 31. The inner lid 30 can be fixed to the outer lid 20 by inserting the first protrusion 31 into the support portion 25 of the outer lid 20 and fastening the second protrusion 32 to the recess 24 of the outer lid 20.

The sheet metal portion of the inner lid 30 is formed with a concave sticky container 33 that protrudes toward the inner pot 3, and a flat plate portion 34 around the sticky container 33.

The sticky rice reservoir 33 is formed in the area from near the center of the inner pot 3 to the first protrusion 31 side at the rear of the rice cooker 100, and has a concave shape that protrudes downward toward the main body 1 side opposite the outer lid 20. The concave shape of the sticky rice reservoir 33 is formed by drawing the plate-shaped sheet metal material using a metal press. The sticky rice reservoir 33 has a structure that has a bottom surface 38 that is a flat surface that protrudes toward the inner pot 3 side, and an inclined portion 39 that is a surface that inclines from the flat portion 34 toward the bottom surface 38. The sticky rice reservoir 33 is configured to be in a position facing the steam path portion 27 of the outer lid 20 when the inner lid 30 is attached to the outer lid 20, and the steam path portion 27 and the sticky rice reservoir 33 form a large space between the outer lid 20 and the inner lid 30.

The flat portion 34 has a structure including a peripheral portion 34a around the sticky reservoir portion 33 which maintains its flat shape, and a flat portion 34b on which a plurality of small projections and recesses are formed.
The peripheral portion 34a is provided at a position facing the end surface 27a of the steam path portion 27 on the inner lid 30 side when the inner lid 30 is attached to the outer lid 20, and becomes a part of the wall surface forming the large space between the outer lid 20 and the inner lid 30. The peripheral portion 34a forms a steam inlet 37, which is a through hole that communicates both sides of the plate-like shape, in the range that becomes the wall surface forming the large space between the outer lid 20 and the inner lid 30 and at the center of the inner kettle 3.
The flat portion 34b is formed with a sensor hole 34c which is a hole that communicates between the outer lid 20 and the inner pot 3. The lid sensor 23 is provided at a position where the temperature inside the inner pot 3 can be detected from the sensor hole 34c when the inner lid 30 is attached to the outer lid 20.

In this embodiment, a gap is provided between the peripheral portion 34a and the end face 27a to prevent heat from the inner lid 30 from being transferred to the outer lid 20. The above configuration is not limited to this structure as long as it can prevent steam from leaking outside the large space while suppressing heat conduction. For example, the steam path portion 27 may be formed from a highly insulating material to connect part or all of the area between the peripheral portion 34a and the end face 27a, or a material with insulating properties may be provided at the tip of the end face 27a to make contact via that material.

In this way, the lid body 2 forms a large space between the inner lid 30 and the outer lid 20 by the steam path section 27 of the outer lid 20 and the sticky rice storage section 33 of the inner lid 30 provided at a position opposite the steam path section 27. This space takes in steam containing sticky rice in the inner pot 3 from the steam inlet 37 of the inner lid 30, promotes separation of the sticky rice from the steam in this space, and discharges the steam to the outside of the rice cooker 100 from the steam outlet 28 provided in the steam path section 27 of the outer lid 20. In other words, this space is a duct that spatially connects the inner pot 3 and the outside of the rice cooker 100, and is a sticky rice recovery structure that recovers sticky rice from the taken-in steam and returns it to the inner pot 3. Therefore, in the rest of this disclosure, this space will be described as a sticky rice recovery space.

Here, in this embodiment, the sticky material recovery space is formed not only by the steam path section 27 and sticky material reservoir section 33, but also by including the peripheral section 34a of the inner lid 30. However, the peripheral section 34a is not a necessary component for forming the sticky material recovery space. For example, the end face 27a of the steam path section 27 can be formed to match the shape of the sticky material reservoir section 33, or the end face 27a of the steam path section 27 can be extended to a position where it protrudes into the recessed space of the sticky material reservoir section 33, thereby forming a sticky material recovery space without including the peripheral section 34a.

The sticky material reservoir 33 has a sticky material return hole 35 formed in the bottom surface 38, which is the flat surface that protrudes most toward the inner pot 3, and which serves as a hole that connects the inside of the inner pot 3 with the sticky material recovery space. The sticky material return hole 35 is equipped with an opening/closing valve 36 that moves up and down according to the steam pressure inside the inner pot 3 to open and close the sticky material return hole 35. The opening/closing valve 36 is structured so that it opens when the pressure inside the inner pot 3 is close to atmospheric pressure and closes when the pressure inside the inner pot 3 is at any value higher than atmospheric pressure. In this embodiment, the opening/closing valve 36 is made of heat-resistant silicone rubber, but it may also be made of, for example, a material with high hydrolysis resistance, such as syndiotactic polystyrene resin (SPS).

The sticky rice return hole 35 is provided at a position that does not overlap the steam exhaust port 28 from the top surface of the rice cooker 100, and is provided on the wall opposite the steam exhaust port 28 across the sticky rice recovery space. Specifically, the sticky rice return hole 35 is provided on the bottom surface 38 of the sticky rice reservoir 33, which is closer to the center of the inner pot 3 than the steam exhaust port 28. Here, the center of the inner pot 3 corresponds to, for example, the central axis if the inner pot is cylindrical. Here, in this disclosure, the positional relationship between the sticky rice return hole 35 and the steam exhaust port 28 is referred to as "diagonally opposite positions" and will be explained.

In this way, by locating the sticky material return hole 35 diagonally opposite the steam exhaust port 28 in the sticky material recovery space, the distance between the steam exhaust port 28 and the sticky material return hole 35 can be increased within the limited space of the sticky material recovery space. As a result, even if outside air enters through the steam exhaust port 28 when the pressure inside the inner pot 3 temporarily drops to the point where the on-off valve 36 opens, the gas in the sticky material recovery space will first flow into the inner pot 3, making it possible to suppress a drop in temperature of the heated items inside the inner pot 3 due to the inflow of outside air.

Furthermore, two steam inlets 37 are provided in the peripheral portion 34a of the flat plate portion 34, close to the connection portion with the inclined portion 38 of the sticky material reservoir 33. In this way, by forming the steam inlet 37 close to the sticky material reservoir 33, the sticky material that separates when passing through the steam inlet 37 can be efficiently collected in the sticky material reservoir 33. In the case of a structure that does not include the peripheral portion 34a as the wall surface of the sticky material recovery space, the steam inlet 37 is provided on the side away from the bottom portion 39 of the inclined portion 38 of the sticky material reservoir 33. By configuring in this way, the sticky material that separates when passing through the steam inlet 37 can be efficiently collected in the sticky material reservoir 33.
The steam inlet 37 has an elliptical shape with a minor axis of 1.5 mm and a major axis of 4 mm.
The steam inlet 37 is provided at a position that does not overlap the steam exhaust port 28 from the top surface of the rice cooker 100 and is diagonally opposite the steam exhaust port 28 on the opposite wall surface across the sticky rice recovery space. In addition, the steam inlet 37 is provided at a position closer to the center of the inner pot 3 than the steam exhaust port 28, similar to the sticky rice return hole 35.

In this way, the sticky rice recovery space formed between the inner lid 30 and the outer lid 20 of the lid body 2 communicates with the inside of the inner pot 3 via the steam inlet 37 and sticky rice return hole 35 formed in the inner lid 30 at a position toward the center of the inner pot 3. On the other hand, the sticky rice recovery space communicates with the outside of the rice cooker 100 via the steam exhaust port 28 provided on the upper surface facing the sticky rice reservoir section 33 of the steam path section 27 of the outer lid 20 at a position that does not overlap with the steam inlet 37 and sticky rice return hole 35 when viewed from above the rice cooker 100 and at a position on the rear side of the outer lid 20.
In addition, the sticky rice returning hole 35 is formed on the steam flow outlet 37 side, which is rearward in the front-to-back direction, and on the inner kettle 3 side, which is lower in the up-down direction, compared to the position of the steam flow inlet 37.

In this way, by locating the steam inlet 37 diagonally opposite the steam exhaust port 28 in the sticky rice recovery space, the distance between the steam exhaust port 28 and the steam inlet 37 can be increased within the limited space of the sticky rice recovery space. As a result, even if the pressure inside the inner pot 3 temporarily drops and outside air enters through the steam exhaust port 28, the gas in the sticky rice recovery space will first flow into the inner pot 3, making it possible to suppress a drop in temperature of the heated items inside the inner pot 3 due to the inflow of outside air.

Furthermore, by providing the sticky paste return hole 35 at a position lower than the steam inlet 37, the sticky paste recovered from the steam can be efficiently returned to the inner pot 3. In the case of a configuration without the flat plate portion 34, the steam inlet 37 can be formed in the slope portion 39 that forms the convex portion of the sticky paste reservoir portion 33 to obtain the same effect.
In addition, by providing the steam inlet 37 on the center side of the inner pot 3, which is farther from the steam exhaust outlet 37 than the steam return hole 35, the distance between the steam inlet 37, which is always open, and the steam exhaust outlet 37 can be increased, so that the temperature drop of the heated object inside the inner pot 3 due to the inflow of outside air can be further suppressed.

In addition, the sticky paste recovery space is formed by an inner lid 30, part of whose wall is heated to a high temperature, so that the invading outside air is heated by the heat of the inner lid 30 as it passes through the sticky paste recovery space. Therefore, even if more outside air subsequently invades the inside of the inner pot 3, the temperature drop of the heated items inside the inner pot 3 can be suppressed.

Next, the rice cooking process in the rice cooker 100 will be described.
A user first puts rice and water into the inner pot 3, and then presses the rice cooking button. The rice cooker 100 then starts the rice cooking process, heating the inner pot 3 using the heating coil 12 and the body heater 13 to cook the rice.

During the rice cooking process, the rice and water in the inner pot 3 are heated by the heating means, and some of the ingredients held in the rice are dissolved in the water by the heat. When the rice is then heated further and reaches or exceeds the evaporation temperature of the water, the water in the inner pot 3 turns into steam. At that time, the rice ingredients dissolved in the water create stickiness, and sticky bubbles that encase the steam are generated in the inner pot 3.

In the rice cooking process, the rice is heated to continuously generate steam, so sticky bubbles are also continuously generated and rise toward the top of the inner pot 3 to fill the upper space inside the inner pot 3. When the sticky bubbles reach the upper outer periphery 3c, which is stepped outward from the upper part of the outer periphery 3b of the inner pot 3, some of the bubbles near the inner pot 3 break and the central part is distributed slightly raised.

The sticky foam that reaches near the center of the inner lid 30 passes through the steam inlet 37 formed in the inner lid 30 and enters the sticky foam recovery space between the top surface of the inner lid 30 and the lid body 2. The sticky foam is broken and liquefied as it passes through the steam inlet 37, and is stored as sticky foam in the sticky foam storage section 33 located below the sticky foam recovery space. The steam that separates from the sticky foam is discharged to the outside through the steam exhaust port 28.

After that, when the rice cooking process is finished, the pressure inside the inner pot 3 drops, the on-off valve 36 drops due to its own weight and the weight of the sticky rice, and the connecting port 35 opens, through which the sticky rice stored in the sticky rice storage section 33 is returned to the inner pot 3. The sticky rice contains the umami components of rice, so by returning this sticky rice to the inner pot 3, delicious rice can be cooked.

Here, the sticky paste return hole 35 is provided in the bottom surface portion 38, which is the lowest part of the sticky paste storage portion 33, so that the structure is capable of efficiently returning the liquefied sticky paste into the inner pot 3. In addition, if the bottom surface portion 38 is inclined so that the amount of depression toward the inner pot 3 increases toward the sticky paste return hole 35, the sticky paste can be returned even more efficiently into the inner pot 3.

Next, the phenomenon of recovering sticky matter in the sticky matter recovery space will be explained with reference to Figures 10 and 11. Figure 10 shows the flow of sticky matter and steam in the steam path, and Figure 11 shows the change in sticky matter bubbles passing through the steam inlet 37.

When the food in the inner pot 3 is heated, the sticky foam in the inner pot 3 fills the upper space in the inner pot 3 due to the internal pressure (a), and after reaching the inner lid 30, it enters the inner lid 30 through the steam inlet 37 (b), as shown in Figure 11.

The sticky bubbles that form inside the inner kettle 3 vary depending on the situation, but most are 4-5 mm or larger in diameter, and in some cases can be several centimeters in size. In contrast, the steam inlet 37 has a short diameter of 1.5 mm, which is very small compared to the diameter of the sticky bubbles. Due to this difference in size, as the sticky bubbles are pushed upward as they pass through the steam inlet 37, the liquid film of the sticky bubbles is stretched and thinned, and eventually the bubbles break. When the sticky bubbles break, the steam inside and the liquid sticky matter are separated.

As shown in FIG. 10, the separated liquid sticky substance flows into the sticky substance reservoir 33 under its own weight, passes through the side portion 39, and accumulates in the bottom portion 38. Meanwhile, the steam that has separated from the sticky substance flows backward and is released to the outside through the steam exhaust port 28.

Thus, even in rice cooker 100 in which the sticky rice recovery space is formed by inner lid 30 and outer lid 20 made of a single plate, by configuring the sticky rice recovery space with a steam inlet 37 and sticky rice return hole 35 diagonally opposite the steam exhaust port 28, the sticky rice can be separated from the steam, recovered, and returned to the inner pot 3. As a result, even though the inner lid 30 is formed from a single plate, the sticky rice can be recovered and returned to the inner pot 3, making it possible to provide delicious rice to the user.

In addition, by locating the sticky rice return hole 35 at a position diagonally opposite the steam exhaust port 28 and toward the center of the inner pot 3 when viewed from the top of the rice cooker 100, it is possible to increase the distance between the steam exhaust port 28 and the sticky rice return hole 35 within the limited space of the sticky rice recovery space. As a result, even if outside air enters through the steam exhaust port 28 when the pressure inside the inner pot 3 temporarily drops to the point where the on-off valve 36 opens, the gas in the sticky rice recovery space will first flow into the inner pot 3, making it possible to suppress a drop in the temperature of the heated items inside the inner pot 3 due to the inflow of outside air.

In addition, by locating the steam inlet 37 at a position diagonally opposite the steam exhaust port 28 and toward the center of the inner pot 3 when viewed from the top of the rice cooker 100, it is possible to increase the distance between the steam exhaust port 28 and the steam inlet 37 within the limited space of the sticky rice recovery space. As a result, even if the pressure inside the inner pot 3 temporarily drops and outside air enters through the steam exhaust port 28, the gas in the sticky rice recovery space will first flow into the inner pot 3, making it possible to suppress a drop in temperature of the heated items inside the inner pot 3 due to the inflow of outside air.

In addition, the steam inlet 37 is located farther away from the steam outlet 28 than the sticky rice return hole 35, which has an on-off valve 36, so that the inflow of outside air into the inner kettle 3 can be further suppressed.

In this way, delicious rice can be provided to users by preventing the temperature of the heated items inside the inner pot 3 from dropping due to outside air entering the inside.

Embodiment 2.
FIG. 12 is a schematic vertical cross-sectional view of the sticky rice recovery space and its surroundings of a rice cooker in embodiment 2.
In embodiment 2, a shielding wall 29 is added to the sticky rice recovery space between the inner lid 30 and the outer lid 20 formed by the sticky rice storage section 33 and the steam path section 27 of the lid body 2 of the rice cooker 100 in embodiment 1.

The shielding wall 29 is disposed in the sticky rice recovery space at a position between the steam inlet 37, sticky rice return hole 35, and steam exhaust port 28. Specifically, the shielding wall 29 is provided so as to protrude toward the sticky rice reservoir 33 from the wall surface of the upper surface of the steam path section 27 between the steam inlet 37, sticky rice return hole 35, and steam exhaust port 28. The shielding wall 29 also provides a gap between itself and at least the inner lid 30 for steam to pass through. In addition, the tip of the shielding wall 29 is structured to protrude downward in the vertical direction to a position closer to the inner kettle 3 than the steam inlet 37.
In addition, the gap between the peripheral portion 34a and the end face 27a is blocked from ventilation by an insulating elastic body 27b provided in the steam path portion 27, preventing steam from escaping from the gap to the outside of the large space.

In this way, by providing the shielding wall 29 at a position sandwiched between the steam inlet 37 and the sticky rice return hole 35 of the sticky rice recovery space and the steam exhaust port 28, the path from the steam exhaust port 28 to the steam inlet 37 and the sticky rice return hole 35 can be lengthened. As a result, even if outside air flows in from the steam exhaust port 28, it is less likely to flow into the inner pot 3 through the steam inlet 37 and the sticky rice return hole 35. Therefore, by providing the shielding wall 29, it is possible to prevent the outside air flowing in from the steam exhaust port 28 from flowing into the inner pot 3, and it is possible to prevent a decrease in the temperature of the heated object inside the inner pot 3 due to the inflow of outside air.

In addition, by configuring the shielding wall 29 so that it protrudes from the steam path section 27 toward the sticky material storage section 3, even if the sticky material liquefies in the sticky material recovery space on the steam exhaust port 28 side of the shielding wall 29, it can be recovered in the sticky material storage section 33.

In addition, because the tip of the shielding wall 29 protrudes further toward the inner pot 3 than the steam inlet 37, the distance between the steam inlet 37, which is always open, and the steam exhaust port 28 can be increased. This makes it possible to further suppress the effect of outside air entering through the steam exhaust port 28 on the temperature drop of the heated items in the inner pot 3. Also, when the outside air entering through the steam exhaust port 28 passes near the tip of the shielding wall 29, it passes close to the inner lid 30, so the outside air can be further warmed by the inner lid 30. This also makes it possible to further suppress the effect of outside air entering through the steam exhaust port 28 on the temperature drop of the heated items in the inner pot 3.

In this way, delicious rice can be provided to users by preventing the temperature inside the inner pot 3 from dropping due to the influence of outside air.

Embodiment 3.
FIG. 13 is a schematic vertical cross-sectional view of the steam path and its surroundings of the rice cooker in the third embodiment.
In the sticky substance recovery space of the second embodiment, the valve body 40 having elasticity is provided on the steam exhaust port 28 side of the shielding wall 29. The valve body 40 in the present embodiment is made of silicone resin, but may be made of a material such as elastic rubber.

The valve body 40 in the third embodiment is provided so as to suppress ventilation between the steam inlet 37 and the sticky rice return hole 35 and the steam outlet 28 when no cooking or other operation is being performed.
The valve body 40 is configured to have a hole in a part thereof to allow ventilation, and is not structured to completely block ventilation. This structure prevents strong pressure from being applied to the valve body 40 due to a pressure drop in the inner kettle 3. The present disclosure does not exclude valve body 40 that completely blocks ventilation.

The valve body 40 is positioned on the steam exhaust port 28 side of the shielding wall 29 in a position that covers at least a portion of the inner lid 30 when viewed from the top of the rice cooker 100, so as to prevent outside air flowing in from the steam exhaust port 28 from coming into contact with the inner lid 30. In this embodiment, the valve body 40 is configured so that one end is fixed to the shielding wall 29 and the other end is deformable. Furthermore, when the pressure inside the inner pot 3 is not high, the tip of the other end of the valve body 40 that is not fixed is placed on the flat plate portion 34 of the inner lid 30 by gravity. Furthermore, in this state, the valve body 40 is positioned so as to cover and conceal the inner lid 30 that faces the steam exhaust port 28 when viewed from above the rice cooker 100.

Next, the function of the valve body 40 will be described with reference to FIG.
FIG. 14 is a schematic vertical cross-sectional view of the steam passage and its surroundings in the rice cooker in the third embodiment, showing a state in which the pressure in the inner pot 3 rises and the valve body 40 is open, as during the rice cooking process.

When the rice cooker 100 is cooking rice, the inner pot 3 is heated by the heating means, generating steam and increasing the pressure inside the inner pot 3. The generated steam flows from inside the inner pot 3 through the steam inlet 37 into the sticky rice recovery space and is discharged outside the rice cooker 100 through the steam outlet 28. At that time, the valve body 40 is displaced in the opening direction when the pressure inside the inner pot 3 rises above a predetermined level. This blocks the steam path when the amount of steam generated is low, thereby preventing excess steam from being discharged.

The valve body 40 is also configured to suppress the flow of air between the steam exhaust port 28 and the steam inlet 37 and sticky return hole 35 when the pressure inside the inner pot 3 is not high. This makes it possible to suppress the temperature drop inside the inner pot 3 throughout operation, thereby reducing the power required for heating. Also, when keeping the pot warm, yellowing can be suppressed by suppressing the inflow of outside air into the inner pot.

The valve body 40 is also configured to suppress the flow of air between the steam exhaust port 28 and the steam inlet 37 and sticky rice return hole 35 when the pressure inside the inner pot 3 drops momentarily. This makes it possible to maintain boiling by suppressing the effect of the temperature drop caused by the inflow of outside air, even if the pressure inside the inner pot 3 suddenly drops during the rice cooking process.

By adopting the configuration of embodiment 3 in this way, it is possible to prevent the temperature inside the inner pot 3 from decreasing due to the inflow of outside air, thereby saving energy and preventing rice deterioration.

In the third embodiment, the valve body 40 is made of an elastic body, but this is not limited thereto. For example, the valve body 40 may be closed by the weight of a weight or may be opened and closed by using an external power source such as a solenoid.

Fourth embodiment
FIG. 15 is a schematic vertical cross-sectional view of the steam path and its surroundings of a rice cooker in accordance with the fourth embodiment.

In the fourth embodiment, the sticky rice storage section 33 has a steam inlet 37 provided above the inclined portion 39 on the center side of the inner pot 3 in the front-to-rear direction as viewed from above the rice cooker 100. In addition, the sticky rice recovery space is provided with a shielding wall 29 that suppresses the flow of air from the steam inlet 37 and the steam exhaust port 28 described in the second embodiment.

When the steam inlet 37 is provided on the sloped portion 39 of the sticky foam storage section 33, the sticky foam that liquefies when passing through the steam inlet 37 flows directly along the sloped portion 39 toward the bottom portion 38. This reduces the amount of sticky foam remaining around the steam inlet 37, making sticky foam bubbles that pass through the steam inlet 37 more likely to break, improving the separation performance between the sticky foam and steam. In addition, because the steam inlet 37 is formed on a slope, gravity is applied diagonally to the sticky foam that passes through the steam inlet 37, making it more likely to break, improving the separation performance between the sticky foam and steam.

In addition, by forming the steam inlet 37 on a slope facing the shielding wall 29, and by positioning the shielding wall 29 in a perpendicular direction as viewed from the steam inlet 37, even if sticky foam or steam is ejected from the steam inlet 37, it will not fly out directly from the steam exhaust port 28. Also, by colliding the ejected sticky foam or steam with the shielding wall 29, it is possible to promote the liquefaction of the sticky foam or steam.

By doing this, the sticky foam separation performance is improved, and a rice cooker 100 can be provided that is less likely to boil over even when boiled over with high heat.

1. Main body,
2 Lid body,
3. Inner pot,
3a bottom,
3b outer periphery,
3c upper outer periphery,
11 Inner pot storage section,
12 heating coil,
13 Body heater,
14 hinge portion,
15 Bottom thermistor,
16 Lid opening button,
17 power supply board,
20 outer cover,
21 Operation panel,
22 Operation board,
23 lid sensor,
24 Inner lid release lever,
25 support part,
26 connection portion,
27 steam path portion,
27a end surface,
27b elastic body,
28 steam exhaust port,
29 shielding wall,
30 inner lid,
31 first protrusion,
32 second protrusion,
33 Sticky storage section,
34, flat plate portion 34a peripheral portion,
34b flat portion 34c sensor hole portion,
35. Oneba return hole,
36 shut-off valve,
37, 37a steam inlet,
38 Bottom surface portion 39 Slope portion 40, 40a Valve body,
100 Rice cooker

Claims (11)

A rice cooker comprising: a main body having an inner pot with an open top, a heating means for heating the inner pot, and an inner pot storage section for accommodating the inner pot; and a lid body that is hinged to the main body and covers the upper part of the main body,
The lid body includes an outer lid that covers the upper surface of the main body, and an inner lid that is detachably attached to the lower surface of the outer lid that is the main body side and is installed in a position that covers the opening on the upper surface of the inner pot,
The outer lid has a steam path portion having a recessed shape formed on the outer lid's side on the main body side, and a steam exhaust port formed on an upper wall surface of the steam path portion and on the rear side of the main body, forming an opening communicating with an upper surface of the lid body,
The inner lid has a sticky rice storage portion having a concave shape with a bottom surface portion protruding toward the inner pot side, which is provided at a position opposite to the steam path portion, and a steam inlet forming an opening communicating with the inside of the inner pot,
This rice cooker is characterized in that the sticky rice storage section is provided with a sticky rice return hole in the bottom portion at a position shifted toward the center of the inner pot when viewed from above relative to the steam exhaust port, which forms an opening that communicates with the inside of the inner pot. 2. The rice cooker according to claim 1, wherein the steam inlet is disposed at a position offset toward the center of the inner pot relative to the steam exhaust port when viewed from above, and on a surface facing the wall surface that forms the steam exhaust port. 3. The rice cooker according to claim 1, wherein the steam inlet is provided at a position closer to the center of the inner pot than the sticky rice returning hole. 4. The rice cooker according to claim 1, wherein the steam inlet is provided closer to the center of the inner pot than the bottom surface of the sticky rice reservoir. The rice cooker according to any one of claims 1 to 4, characterized in that the steam path section is provided with a shielding wall that protrudes downward from the upper wall surface toward the inner pot side at a position between the sticky rice return hole and the steam exhaust port. The rice cooker according to claim 5, wherein the shielding wall has a tip that protrudes into the recess of the sticky rice reservoir . The rice cooker according to claim 5 or 6, characterized in that the tip of the shielding wall protrudes beyond the steam inlet toward the inner pot. The rice cooker according to any one of claims 5 to 7, characterized in that the steam path portion is provided with a valve body on the steam exhaust port side of the shielding wall. 9. The rice cooker according to claim 1, wherein the steam inlet is formed on a slope of the sticky rice reservoir. 9. The rice cooker according to claim 6, wherein the steam inlet is formed in a slope portion that is inclined toward the shielding wall. The rice cooker according to any one of claims 1 to 10, characterized in that the inner pot has a bottom, a cylindrical outer periphery continuing from the bottom, and an upper outer periphery that is stepped outward from the upper end portion of the outer periphery.

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