JP7227493B2 - rice cooker - Google Patents

Description

The present invention relates to the technology of rice cookers.

Conventionally, rice cookers have been improved in various ways in order to meet the need to eat more delicious rice. For example, it is as described in Patent Document 1. In addition, some conventional rice cookers have a ceramic inner pot for cooking rice (earthenware pot), which is characterized by being able to cook delicious rice just like it was cooked in an earthenware pot. For example, it is as described in Patent Documents 2 and 3.

It is effective as a method for eating more delicious rice to cook only the amount of rice to be eaten at each meal and always eat freshly cooked rice. However, with the conventional rice cookers disclosed in Patent Documents 1 to 3, when cooking an amount of rice close to the maximum amount of rice to be cooked (5 go or 5.5 go), good rice cooking results are obtained (that is, However, when a small amount of rice such as 1 go is cooked, there is a problem that the taste of the rice deteriorates compared to when the rice is cooked with the maximum amount of rice. Furthermore, when a small amount of rice, which is less than the maximum amount of rice to be cooked, is kept warm, the portion where no rice exists in the rice cooking space inside the inner pot becomes wider, and the portion near the lower portion of the rice cooking space near the rice and the portion away from the rice. A temperature difference occurs between the upper part and the upper part. Due to this temperature difference, condensed water tends to form inside the inner pot. I have a problem.

In other words, with conventional rice cookers, it is difficult to cook a small amount of rice of about 1 go deliciously, and it is also difficult to keep a small amount of rice of about 1 go warm in a delicious state.

JP 2018-201667 A JP 2015-217151 A JP 2015-226593 A

The present invention has been made in view of such current problems. It provides a rice cooker.

A rice cooker according to the present invention includes an inner pot having a bottom located at a lower end and an opening located at an upper end;
A rice cooking space formed by an inner lid that seals the opening of the inner pot, a heating unit that heats the inner pot, and the inner pot and the inner lid is in contact with the bottom and accommodates food to be cooked. and a non-rice-cooking space, which is a space in contact with the inner lid and located above the small rice-cooking space, and a position inside the rice-cooking space of the inner pot, a locking portion protruding radially inward from the inner diameter of the opening of the inner pot and capable of locking the inner lid, wherein the inner pot is provided at an upper end of the locking portion; A planar locking surface formed thereon and a recess formed by recessing a space between the opening and the locking portion radially outward from an inner diameter of the opening are formed, and the recess and the locking portion are formed. are continuous, and the locking surface is expanded radially outward from the opening.

According to the rice cooker of the present invention, since the concave portion is formed in addition to the engaging surface in the inner pot, when the inner lid is removed, a wide area is secured for collecting sauce in the engaging portion. As a result, it becomes difficult for condiments and the like adhering to the inner lid to drip onto the rice, and it is possible to prevent the deterioration of the taste of the cooked rice. As a result, even if the rice is cooked in a small amount with respect to the capacity of the inner pot, delicious rice can be automatically cooked, and the rice can be kept warm while maintaining a delicious state.

The present invention further comprises a control device for controlling the operation of the heating section, the heating section includes a lid heater for heating the inner pot from above, and the control device controls the use of the inner lid. It is preferable that the heating amount of the lid heater is reduced in the heat retaining step after rice is cooked without using the inner lid as compared with the heat retaining step after rice is cooked without using the inner lid.

According to this configuration, in the rice cooking space in the inner pot, the boundary between the portion heated by the lid heater at the top and the portion near the rice at the bottom can be the vicinity of the recess and the locking surface. The tsuyu can be efficiently held by the concave portion and the locking surface. As a result, the rice can be kept warm while maintaining its delicious state.

In the present invention, the inner lid has a disk-shaped horizontal plate portion, a vertical plate portion surrounding the outer periphery of the horizontal plate portion, and a flange projecting radially outward from the vertical plate portion, and It is preferable that an enlarged-diameter portion, which is formed by enlarging the vertical plate portion to have an outer diameter that substantially matches the inner diameter of the engaging portion, is formed adjacent to the vertical plate portion and the flange portion.

According to this configuration, when the recessed portion is provided in the inner pot, rattling of the inner lid locked by the locking portion can be suppressed. By suppressing rattling of the inner lid, it is possible to suppress the occurrence of a gap between the inner pot and the inner lid, and to secure the airtightness of the rice cooking space, thereby making it possible to cook a small amount of rice deliciously. can be done.

In the present invention, the inner pot is preferably made of ceramic.

According to this configuration, even if the rice is cooked in a small amount with respect to the capacity of the inner pot made of ceramic, delicious rice can be automatically cooked, and the rice can be kept warm while maintaining the delicious state.

According to the rice cooker of the present invention, it is possible to cook deliciously a small amount of rice of about 1 go, which is less than the maximum amount of rice to be cooked, and to keep the rice warm while maintaining a delicious state.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows the rice cooker which concerns on this invention. A right side sectional view showing a rice cooker provided with an inner pot and an inner lid. Control block diagram of the rice cooker. The bottom view which shows the cover part (state which attached the inner cover) of the rice cooker. The bottom view which shows the cover part (with the inner cover removed) of the rice cooker. A view showing the inner hook, (A) a plan view, and (B) a cross-sectional view taken along the line AA in FIG. 6(A). The figure which shows an inner cover, (A) Top view, (B) Side view. Cross-sectional view showing the inner lid, (A) a cross-sectional view taken along line BB in FIG. 7(A), and (B) a cross-sectional view taken along line CC in FIG. 7(A). The top view which shows the combination state of an inner pot and an inner lid. FIG. 10 is a cross-sectional view taken along line DD in FIG. 9, showing the combined state of the inner hook and the inner lid; Cross-sectional schematic diagram showing the state of formation of the rice cooking space by the combination of the inner pot and the inner lid, (A) Diagram showing the rice cooking space without the inner lid inner lid, (B) Rice cooking space with the inner lid inner lid illustration. Schematic cross-sectional views showing the temperature distribution in the rice cooking space after rice is cooked, (A) when the heating amount of the lid heater is suppressed, (B) when the heating amount of the lid heater is not suppressed.

[Overall configuration of rice cooker]
A rice cooker 1 shown in FIGS. 1 and 2 is an embodiment of the rice cooker according to the present invention, and includes a rice cooker body 2 and a lid 3 . For convenience of explanation, the front-rear direction, the left-right direction, and the up-down direction are defined for the rice cooker 1 as indicated by the arrows shown in FIGS. 1 and 2 . Also, in the following description, front, rear, left, right, top, bottom, etc. refer to states in which each part constituting the rice cooker 1 is assembled in a predetermined position when the rice cooker 1 is used. Orientation is indicated as a reference.

The rice cooker main body 2 is a portion forming part of the outer shell of the rice cooker 1, is arranged below the lid 3, and forms a space for accommodating an inner pot (an inner pot 4 described later). The lid body 3 is a part that forms part of the outer shell of the rice cooker 1, is arranged above the rice cooker main body 2, and seals the housing space of the inner pot formed inside the rice cooker main body 2. configured as possible.

The rice cooker 1 includes an inner pot 4, a container member 5, a heating section 6, an inner lid 7, an inner lid 8, and a control device 9, as shown in FIGS. The container member 5 , part of the heating unit 6 , and the control device 9 are housed inside the rice cooker main body 2 . The container member 5 housed in the rice cooker main body 2 is a container-shaped member for keeping the inner pot 4 warm or storing heat, and is part of the space for housing the inner pot 4 in the rice cooker main body 2. constitutes A portion of the heating unit 6 is housed inside the lid 3 . The inner lid 7 is arranged on the lower surface of the lid body 3 (the surface located inside the rice cooker 1 when the rice is cooked).

The lid 3 has a hinge 3a. The lid 3 is connected to the upper portion of the rear end of the rice cooker body 2 via a hinge 3a, and is configured to be rotatable between postures facing in the front-rear direction and substantially in the vertical direction.

The inner pot 4 is a portion forming part of a space for cooking rice in the rice cooker 1 (hereinafter referred to as a rice cooking space), and is used while being housed in the rice cooker main body 2 . In addition, the rice cooker 1 is provided with an inner lid 8 that is arranged inside the inner pot 4 for use. The rice cooking space is a space for cooking food (for example, rice and water), and is a space that allows convection of the food during cooking. It should be noted that the rice cooking space of the rice cooker 1 can also be used to heat and cook foods other than rice.

The heating unit 6 is means for heating the inner pot 4, and is composed of main heaters 6a and 6b, a side heater 6c, a shoulder heater 6d, and a lid heater 6e. The main heaters 6a and 6b constitute a series of main heaters. The main heater 6a is arranged below the container member 5, and the main heater 6b is curved between the bottom portion 5a and the side portion 5b of the container member 5. It is arranged on the back side of the portion 5c. In addition, the heating unit 6 has a side heater 6c arranged on the back side of the side portion 5b of the container member 5, a shoulder heater 6d arranged above the container member 5 in the rice cooker body 2, and a lid heater 6e arranged on the lid body 3. is placed inside the

The heating section 6 induction-heats the bottom portion 5a of the container member 5 with the main heater 6a, induction-heats the curved portion 5c of the container member 5 with the main heater 6b, and induction-heats the side portion 5b of the container member 5 with the side heater 6c. Then, the inner pot 4 is heated by heating the inside of the inner pot 4 from the lid body 3 side. Further, the heating section 6 heats the shoulder portion of the inner pot 4 with the shoulder heater 6d. The outputs of the heaters 6a, 6b, 6c, 6d, and 6e constituting the heating unit 6 can be individually controlled by the control device 9 in accordance with user settings, programs preset in the control device 9, and the like. .

As shown in FIG. 2 , the inner lid 7 is arranged on the lower surface of the lid 3 . 4 and 5, the inner lid 7 is detachable from the lid 3. As shown in FIGS. As shown in FIGS. 2 and 4, the outer peripheral portion of the inner lid 7 is formed with a ring-shaped upper seal portion 7a extending radially outward and a ring-shaped side seal portion 7b extending downward. The upper seal portion 7a and the side seal portion 7b seal the gap between the inner lid 7 and the inner pot 4. As shown in FIG.

Further, a lid heater 6 e that constitutes a part of the heating section 6 is arranged inside the inner lid 7 of the lid body 3 .

Furthermore, as shown in FIGS. 2 to 4, the lid 3 includes a steam exhaust unit 13 for exhausting steam generated during rice cooking. The steam discharge unit 13 has two large and small steam discharge ports 13a and 13b. Each of the steam discharge ports 13a and 13b is opened to the lower surface of the inner lid 7, and the steam port 3c formed on the upper surface of the lid 3 passes through the exhaust passage 3b formed inside the lid 3. communicates with

The steam discharge unit 13 includes valve bodies 13c and 13d for opening and closing the respective steam discharge ports 13a and 13b. , the steam outlets 13a and 13b can be opened and closed. A part of the steam discharge unit 13 is provided on the inner lid 7 . The inner lid 7 is detachable from the lid body 3, and when the inner lid 7 is removed as shown in FIG. 5, the lid sensor 12 arranged in the exhaust passage 3b is exposed.

In the rice cooker 1, when the lid body 3 is closed with the inner pot 4 housed in the rice cooker main body 2, the upper surface seal portion 7a of the inner lid 7 comes into contact with the upper end portion 4f of the inner pot 4, The side seal portion 7 b abuts against the inner peripheral portion of the hook 4 , and the upper opening of the inner hook 4 is sealed by the inner lid 7 . At this time, a rice cooking space (a rice cooking space CA to be described later) in the rice cooker 1 is formed by the inner pot 4 and the inner lid 7 .

As shown in FIG. 3, the control device 9 is a device for controlling the rice cooking operation of the rice cooker 1, and is composed of a so-called microcomputer. The control device 9 is connected to the heating section 6, the operating section 10, the center sensor 11, the lid sensor 12, the steam discharge unit 13, and the like.

As shown in FIGS. 1 and 3, the operation unit 10 is a part for the user to give operation instructions to the rice cooker 1, and includes an operation switch 10a, a display unit 10b, and a notification unit 10c. The user selects the desired degree of cooking by operating the operation switch 10a. Specifically, the rice cooker 1 is equipped with a small-volume rice cooking mode in which 1 go of rice can be cooked deliciously. A rice cooking space is divided and rice is cooked in a smaller rice cooking space suitable for cooking a small amount of rice. The display unit 10b is configured by a screen that can display the selection of the degree of rice cooking by the user, the progress of rice cooking, and the like. The notification unit 10c is a part for notifying the user of the completion of cooking, an abnormality of the rice cooker 1, etc. by sound or display, and is configured by a speaker, an indicator lamp, and the like.

When the user selects the rice cooking mode using the operation unit 10, the control device 9 adjusts the output of the heating unit 6 according to the program corresponding to the selected rice cooking mode. Further, the detection results of the center sensor 11 and the lid sensor 12 are fed back to the control device 9, and the output to the heating section 6 is further adjusted. The center sensor 11 is a temperature sensor that detects the temperature of the inner pot 4, and the lid sensor 12 is a temperature sensor that detects the temperature of the gas (steam) discharged from the inner pot 4 via the steam discharge unit 13. .

The rice cooker 1 has modes such as a small rice cooking mode suitable for cooking a small amount of rice of about 1 go and a normal rice cooking mode suitable for cooking a normal amount of rice. For this reason, the control device 9 is preset with a program corresponding to each mode such as a small amount of rice cooking mode and a normal rice cooking mode. The control device 9 automatically selects a program according to the mode selected by the user and controls the heating section 6 .

[Detailed configuration of the inner pot]
Here, the inner hook 4 will be described in more detail. The inner pot 4 is an embodiment of the inner pot that constitutes the rice cooker 1 .

As shown in FIGS. 6 and 7, the inner pot 4 is a substantially cylindrical container with a bottom for containing water and cooked food such as rice, and has a bottom portion 4a, a side portion 4b, and a curved portion 4c. ing. The inner pot 4 is made of ceramic (a so-called clay pot). The inner pot 4 has a bottom portion 4a at its lower end and an opening 4h at its upper end. An opening 4 h of the inner pot 4 is configured to be sealed by an inner lid 7 .

In the rice cooker 1, since the inner pot 4 is made of ceramic, delicious rice can be cooked even when a small amount of rice is cooked by the action of radiant heat radiated from the ceramic. The rice cooker 1 can automatically cook rice having texture as if it was cooked in an earthenware pot without worrying about the heat level. In the rice cooker 1, as shown in this embodiment, the inner pot 4 is preferably made of ceramic, but in the rice cooker 1, an inner pot made of a material other than ceramic (for example, made of metal) is used. can also

A locking portion 4d is formed on the inner peripheral surface of the side portion 4b of the inner hook 4. As shown in FIG. The locking portion 4d is a ring-shaped projection for locking the inner lid 8. As shown in FIG. At the upper end of the side portion 4b of the inner hook 4, a collar portion 4e and an upper end portion 4f are formed. The collar portion 4 e is a part that serves as a clue when the user holds the inner pot 4 . The upper end portion 4f is a portion that abuts on the upper surface seal portion 7a of the inner lid 7, and has an inclination that is slightly downward toward the radially inner side of the inner hook 4. As shown in FIG.

In addition, the locking portion 4d also functions as a weir that prevents rice from flowing out when the inner pot 4 is used to wash the rice. When a scale indicating the amount of water to be cooked is provided on the inner wall of the inner pot 4, it is preferable that the engaging portion 4d is provided above the position of the scale (that is, a position that does not interfere with the scale).

The opening 4h is a portion opened at the upper end of the inner hook 4, and has an inner diameter d1 as shown in FIG. 6(B). The engaging portion 4d is formed below the opening portion 4h and has an inner diameter d2. In addition, the engaging portion 4d of the inner hook 4 has an inner diameter d2. The inner diameter d2 of the engaging portion 4d is smaller than the inner diameter d1 of the opening 4h. Therefore, the top of the engaging portion 4d protrudes inward from the opening 4h in the plan view and side cross-sectional view of the inner hook 4 .

A substantially planar locking surface 4g is formed on the upper portion of the locking portion 4d. The locking surface 4g is a planar portion that contacts the collar portion 8g of the inner lid 8 and locks the inner lid 8 to the inner hook 4. As shown in FIG. In addition, the angle of the plane of the engaging surface 4g is substantially horizontal so that the engaging surface 4g functions as a part for collecting the concoction on its upper part, and so that the concoction does not flow down below the engaging surface 4g due to its own weight. It is preferable to

Further, the inner hook 4 has a recess 4k between the locking surface 4g and the opening 4h. The recess 4k is a portion formed by recessing a space between the lower end of the opening 4h and the engaging portion 4d in the radial direction, and has an inner diameter d3 larger than the inner diameter d1 of the opening 4h. The lower end of the concave portion 4k is continuous with the locking surface 4g of the locking portion 4d. That is, the locking surface 4g of the locking portion 4d constitutes a planar portion that is expanded to a range that is expanded outward from the opening 4h of the inner diameter d1. As a result, it is possible to accumulate a large amount of soup, suppress the occurrence of dripping of soup on the rice, and improve the heat retention of the rice.

[Detailed configuration of inner lid]
Next, the inner lid 8 will be described in further detail. The inner lid 8 is an embodiment of the inner lid that constitutes the rice cooker 1 .

As shown in FIGS. 7 and 8, the inner lid 8 has a horizontal plate portion 8a and a vertical plate portion 8b. The horizontal plate portion 8a is composed of a substantially disc-shaped member, and the vertical plate portion 8b is composed of a cylindrical member whose diameter decreases from the top to the bottom. The inner lid 8 is configured by arranging a substantially disk-shaped horizontal plate portion 8a so as to surround it with a cylindrical vertical plate portion 8b. are doing. The inner lid 8 is made of ceramic like the inner pot 4 .

In the rice cooker 1, by making the inner lid 8 made of ceramic, it is possible to eliminate the difference in thermal conductivity when combined with the inner pot 4, which is also made of ceramic. 4 can be reduced. Since the temperature difference between each part during heat retention is a factor that causes the formation of thickening, suppressing the temperature difference suppresses the formation of thickening, thereby making it possible to keep the rice more delicious.

The horizontal plate portion 8a has an upper surface 8c and a lower surface 8d, and is provided with a handle portion 8e protruding upward from the upper surface 8c. The upper surface 8c is a convex curved surface that is downwardly curved radially outward from the boundary with the handle portion 8e to the vertical plate portion 8b. The lower end of the vertical plate portion 8b is positioned below the lower end of the horizontal plate portion 8a. For this reason, a concave portion is formed at the lower end of the inner lid 8 by the lower surface 8d of the horizontal plate portion 8a and the vertical plate portion 8b. A substantially conical side peripheral surface 8h is formed on the outer peripheral portion of the inner lid 8 by the outer peripheral surface of the vertical plate portion 8b.

The inner lid 8 has a plurality of (three in this embodiment) steam holes 8f passing through the horizontal plate portion 8a near the boundary between the horizontal plate portion 8a and the vertical plate portion 8b. In this embodiment, the three steam holes 8f, 8f, 8f are arranged around the center P of the inner lid 8 at equal intervals (120° pitch).

In addition, the inner lid 8 has a flange portion 8g that protrudes radially outward from the side peripheral surface 8h at the upper end of the vertical plate portion 8b. The collar portion 8g has a ring shape as a whole and has an outer diameter d4. The outer diameter d4 of the collar portion 8g is larger than the inner diameter d2 of the engaging portion 4d of the inner hook 4 and smaller than the inner diameter d3 of the recess 4k. In the rice cooker 1, by making the outer diameter d4 of the flange 8g smaller than the inner diameter d3 of the recess 4k, the inner lid 8 can be arranged in the engaging portion 4d. In addition, in the rice cooker 1, by making the outer diameter d4 of the collar portion 8g larger than the inner diameter d2 of the engaging portion 4d, the inner lid 8 extends beyond the engaging portion 4d toward the bottom portion 4a of the inner pot 4. It prevents it from falling off.

Further, the inner lid 8 is provided with an enlarged diameter portion 8k whose diameter is enlarged so as to fill the space between the side peripheral surface 8h and the flange portion 8g. The enlarged diameter portion 8k is a convex portion adjacent to the side peripheral surface 8h and the flange portion 8g, and is indicated by being filled with ink in FIGS. 8A and 8B. The enlarged-diameter portion 8k is configured such that the outer diameter d5 of the portion where the diameter is enlarged most in the radial direction is smaller than the inner diameter d2 of the locking portion 4d (that is, d5<d2). Here, in the rice cooker 1, by minimizing the difference in dimension between the outer diameter d5 of the enlarged diameter portion 8k and the inner diameter d2 of the locking portion 4d, the large diameter portion 8k suspends from the locking portion 4d. This suppresses the displacement (rattling) of the inner lid 8 in the radial direction.

[Combination state of inner pot and inner lid]
As shown in FIGS. 9 and 10, the inner lid 8 is suspended with respect to the inner hook 4 by placing the collar portion 8g on the locking surface 4g of the inner hook 4, and It is arranged at a predetermined position in the middle. The upper end of the inner lid 8 is positioned below the upper end of the inner hook 4 while the flange 8g is locked by the locking portion 4d.

The radial displacement of the inner lid 8 is restricted by the enlarged diameter portion 8k coming into contact with the top portion of the locking portion 4d. Although the enlarged diameter portion 8k shown in the present embodiment is configured to be provided continuously along the entire circumference of the side peripheral surface 8h, it can be divided into a plurality of portions as long as the displacement of the inner lid 8 can be controlled. It is good also as a structure provided.

[Description of the rice cooking space]
Next, the rice cooking space of the rice cooker 1 will be described.

When the inner lid 8 is not used, the rice cooker 1 forms the rice cooking space CA by sealing the upper opening of the inner pot 4 with the inner lid 7 as shown in FIG. 11(A). The rice cooking space CA is a space in which an amount of food (rice, water, etc.) corresponding to the maximum amount of rice to be cooked in the inner pot 4 can be cooked. When the inner lid 8 is not used, the rice cooker 1 can cook rice in the rice cooking space CA, and the rice and water are heated and cooked while the rice and water convect in the rice cooking space CA.

When the inner lid 8 is used, the rice cooker 1 separates the rice cooking space CA formed by the inner pot 4 and the inner lid 7 from the small rice cooking space CA1 by the inner lid 8, as shown in FIG. 11(B). It can be divided into a rice cooking space CA2. The small rice-cooking space CA1 is a lower portion of the rice-cooking space CA and is in contact with the bottom portion 4a. The non-rice-cooking space CA2 is an upper portion of the rice-cooking space CA and is in contact with the inner lid 7 .

As shown in FIG. 11(B), when the flange 8g is locked by the locking part 4d and the inner lid 8 is combined with the inner pot 4 at a predetermined position, the entire inner lid 8 is positioned inside the rice cooking space CA. placed. The inner lid 8 divides the rice cooking space CA into a lower portion and an upper portion, forming a small rice cooking space CA1 having a smaller volume than the rice cooking space CA and a non-cooking space CA2 that is basically not used for cooking.

The small rice-cooking space CA1 is a space suitable for cooking a small amount (for example, 1 go) of food (rice, water, etc.) compared to the maximum rice-cooking amount of the inner pot 4 . When the inner lid 8 is used, the rice cooker 1 can cook rice only in the small rice-cooking space CA1, and the rice and water are heated and cooked in the small rice-cooking space CA1 while convection. In addition, when the inner lid 8 is used, the rice cooker 1 does not put food into the non-rice-cooking space CA2, and constitutes a distribution path for the steam emitted from the small rice-cooking space CA1 toward the steam discharge unit 13. there is

That is, the rice cooker 1 shown in this embodiment includes an inner pot 4 having a bottom portion 4a located at the lower end and an opening portion 4h located at the upper end, an inner lid 7 sealing the opening portion 4h of the inner pot 4, A heating unit 6 for heating the inner pot 4 is provided, and cooking is performed in the rice cooking space CA formed by the inner pot 4 and the inner lid 7 . The rice cooker 1 includes a rice cooking space CA that is in contact with the bottom portion 4a and is a space in which cooked food is stored, and a non-cooking space that is in contact with the inner lid 7 and is located above the small rice cooking space CA1. It has an inner lid 8 that partitions into a space CA2. The inner pot 4 is formed with a locking portion 4d capable of locking the inner lid 8 at a position inside the rice cooking space CA. The inner lid 8 is locked by the locking portion 4d and arranged inside the rice cooking space CA. With such a configuration, the rice cooker 1 can automatically cook delicious rice even if the rice is cooked in a small amount with respect to the capacity of the inner pot 4 .

[Role of non-cooking space]
In the rice cooker 1, steam emitted from the small rice cooking space CA1 through the steam holes 8f of the inner lid 8 is led to the steam discharge unit 13 through the non-rice cooking space CA2. That is, the rice cooker 1 has a non-rice-cooking space CA2 serving as a steam discharge path. Since the steam in the non-rice-cooking space CA2 is used to heat the inner lid 8 from above, it is possible to evaporate and reduce the condensation accumulated on the upper surface 8c of the inner lid 8 and the handle portion 8e.

[Effect of providing concave part]
Since the inner hook 4 is provided with the concave portion 4k, the area of the locking surface 4g of the locking portion 4d is enlarged. In the rice cooker 1, when the inner lid 8 is removed after the rice is cooked in the small-volume rice cooking mode, the recess 4k and the locking surface 4g function as parts for receiving the scum generated in the inner pot 4. The area of the part that receives Tsuyu has been expanded. Further, since the concoction accumulated on the engaging surface 4g evaporates due to the heat stored in the inner pot 4, the engaging surface 4g also functions as a portion for evaporating the concoction. In the rice cooker 1, by providing the concave portion 4k and the locking surface 4g, it is possible to prevent the flavor of the cooked rice from deteriorating due to dripping of sauce onto the cooked rice.

[Effects of providing the enlarged diameter part]
By providing the recessed portion 4k in the inner hook 4, there is a margin that allows the collar portion 8g of the inner lid 8 to be displaced radially outward. Displacement (rattling) of the inner lid 8 is suppressed by bringing the enlarged diameter portion 8k into contact with the top portion. If the inner lid 8 rattles during rice cooking, a gap is generated between the inner pot 4 and the inner lid 8, and the rice cannot be cooked while the small rice cooking space CA1 is kept constant. is provided, the small rice-cooking space CA1 can be kept constant, thereby making it possible to cook delicious rice.

That is, the rice cooker 1 includes an inner pot 4 having a bottom portion 4a and an opening 4h, an inner lid 7 sealing the opening 4h of the inner pot 4, a heating portion 6 for heating the inner pot 4, and an inner pot. The rice cooking space CA formed by 4 and the inner lid 7 is divided into a small rice cooking space CA1 that is in contact with the bottom part 4a and is a space for storing the cooked food, and a space that is in contact with the inner lid 7 and is located above the small rice cooking space CA1. An inner lid 8 that divides into a non-rice cooking space CA2, and a position inside the rice cooking space CA of the inner pot 4, protruding radially inward from the inner diameter d1 of the opening 4h of the inner pot 4, and the inner lid 8 The inner hook 4 has a planar locking surface 4g formed at the upper end of the locking portion 4d, and a space between the opening 4h and the locking portion 4d. A recess 4k is recessed radially outward from the inner diameter d1 of the opening 4h. It is

According to the rice cooker 1 having such a configuration, even when cooking a small amount of rice, which is less than the capacity of the inner pot 4, about 1 go, delicious rice can be automatically cooked and delicious. It is possible to keep the rice warm while maintaining the condition.

Further, in the rice cooker 1, the inner lid 8 includes a disk-shaped horizontal plate portion 8a, a vertical plate portion 8b surrounding the outer periphery of the horizontal plate portion 8a, and a collar portion 8g protruding radially outward from the vertical plate portion 8b. , and the enlarged diameter portion 8k formed by enlarging the vertical plate portion 8b to an outer diameter d4 substantially matching the inner diameter d2 of the locking portion 4d is adjacent to the side peripheral surface 8h of the vertical plate portion 8b and the collar portion 8g. formed by

According to such a configuration, when the recess 4k is provided in the inner hook 4, rattling of the inner lid 8 locked by the locking portion 4d can be suppressed. By suppressing rattling of the inner lid 8, the generation of a gap between the inner pot 4 and the inner lid 8 is suppressed, and by keeping the rice cooking space CA constant, a small amount of rice can be cooked deliciously. In addition, it is possible to keep a small amount of rice warm while keeping it in a delicious state.

[Lid heater control method]
In the rice cooker 1, when the small-volume rice cooking mode is selected, the control device 9 controls the amount of heating by the lid heater 6e in the subsequent heat-retaining control of rice compared to when the normal rice-cooking mode is selected. , is configured to be low. It should be noted that the heating amount of the lid heater 6e in the heat retention control can be configured to be the same in both the small amount rice cooking mode and the normal rice cooking mode. FIGS. 12A and 12B schematically show the temperature distribution in the rice cooking space CA within the inner pot 4 after the small amount of rice cooking mode is selected. In the small-volume rice cooking mode, the amount of cooked rice is small, so the proportion of the space other than the portion occupied by the rice in the rice cooking space CA is higher than when the rice is cooked in the normal rice cooking mode.

FIG. 12(B) schematically shows the temperature distribution in the inner pot 4 when the heating amount by the lid heater 6e is the same as when rice is cooked in the normal rice cooking mode. In this case, "warm air" is accumulated in the upper area affected by heating by the lid heater 6e, and "cold air" whose temperature is lower than that of "warm air" is accumulated in the lower area. there is A temperature difference is generated between the area where the "warm air" accumulates and the area where the "cold air" accumulates. In FIGS. 12(A) and 12(B), the boundary of the portion where this temperature difference occurs is represented as a "boundary", and it has been confirmed that condensation is likely to occur in the vicinity of this "boundary".

FIG. 12(A) schematically shows the temperature distribution in the inner pot 4 when the heating amount by the lid heater 6e is kept lower than when the normal rice cooking mode is selected. In the rice cooker 1, by suppressing the heating amount of the lid heater 6e, the area where "warm air" accumulates narrows in the upward direction, the "boundary" between the "warm air" and the "cold air", and the recess 4k and the locking surface 4g. It is pulled up to the vicinity of the existing area. With such a configuration, the rice cooker 1 is configured to effectively hold the stains generated in the vicinity of the "boundary" by the concave portion 4k and the engaging surface 4g.

In the configuration shown in FIG. 12(B), the amount of tsuyu accumulated in the recess 4k and the locking surface 4g was about 0.1 g, whereas in the configuration shown in FIG. The amount of congee collected on the surface 4g increased to about 0.4g. From this result, when a small amount of rice of about 1 go is cooked, the amount of heating by the lid heater 6e is suppressed, and it is configured to cause condensation in the vicinity of the area where the recess 4k and the locking surface 4g exist. So, it is possible to suppress the dripping of tsuyu on the cooked rice. As a result, a small amount of deliciously cooked rice of about 1 go can be kept warm in a delicious state.

That is, the rice cooker 1 further includes a control device 9 that controls the operation of the heating portion 6. The heating portion 6 includes a lid heater 6e that heats the inner pot 4 from above. In the heat retention process after rice cooking using the lid 8, the heating amount of the lid heater 6e is reduced compared to the heat retention process after rice cooking without using the inner lid 8. - 特許庁

According to the rice cooker 1 having such a configuration, in the rice cooking space CA in the inner pot 4, the "boundary" between the portion heated by the lid heater 6e at the top and the portion near the rice at the bottom is defined as the recess 4k and It can be positioned in the vicinity of the engaging surface 4g, and the resulting tsunami can be efficiently held by the recessed portion 4k and the engaging surface 4g. As a result, a small amount of deliciously cooked rice of about 1 go can be kept warm while maintaining its delicious state.

In addition, in the rice cooker 1, since the inner pot 4 is made of ceramic, even if the rice is cooked in a small amount, which is smaller than the capacity of the inner pot 4 made of ceramic, delicious rice is automatically cooked and a delicious state is maintained. It can keep warm.

The rice cooker 1 shown in this embodiment can cook a small amount of rice, about 1 go, deliciously. Therefore, there is a problem that the taste of deliciously cooked rice deteriorates. For this reason, the rice cooker 1 has a mechanism that prompts the user to take out the inner lid 8 immediately after the rice cooking is completed. Specifically, in the rice cooker 1 , opening and closing of the lid 3 is detected by a tilt sensor (not shown) incorporated in the lid 3 . In the rice cooker 1, after the rice-cooking process in the small-volume rice-cooking mode is completed, a voice announcement prompting stirring of the cooked rice is periodically played until the lid body 3 is opened. there is At the same time, the rice cooker 1 operates the cooling fan 15 (see FIG. 2) arranged in the rice cooker main body 2 until the lid 3 is opened, thereby lowering the temperature of the inner pot 4 and the like. , is configured to be able to suppress the generation of burnt.

In addition, the rice cooker 1 is configured to change the contents of the heat retention control depending on whether or not the opening/closing of the lid 3 is detected by an inclination sensor (not shown) incorporated in the lid 3 after the completion of rice cooking. ing. For example, when the tilt sensor does not detect opening/closing of the lid body 3, the controller 9 determines that the inner lid 8 has not yet been taken out, and performs heat retention control suitable for the state in which the inner lid 8 is present. . On the other hand, when the tilt sensor detects opening and closing of the lid 3, the controller 9 determines that the inner lid 8 has been taken out, and performs heat retention control suitable for the state without the inner lid 8.例文帳に追加A configuration without the tilt sensor, the voice announcement, the cooling fan 15, and the like may be used. Further, a sensor other than the tilt sensor (for example, the lid sensor 12) may be configured to detect that the lid 3 is opened and closed.

Alternatively, when the inclination sensor detects opening and closing of the lid body 3, the rice cooker 1 uses the temperature detected by the center sensor 11 and the lid sensor 12 to detect the temperature change in the inner pot 4, and the control device 9 determines whether or not the inner lid 8 is taken out based on the temperature change, and performs heat retention control suitable for the state without the inner lid 8, or performs heat retention control suitable for the state with the inner lid 8. or may be configured to determine. The control device 9 determines the presence or absence of the inner lid 8 by utilizing the fact that the temperature change in the inner pot 4 is gentler than when the inner lid 8 is removed when the inner lid 8 is present. be able to.

In addition, the rice cooker 1 is configured to reliably prevent the inner lid 8 from being set in the wrong direction by adjusting the dimensions of the inner pot 4 and the inner lid 8 . Specifically, as shown in FIGS. 11A and 11B, A is the thickness of the flange 8g of the inner lid 8, B is the height of the recess 4k of the inner pot 4, and B is the thickness of the entire inner lid 8. The dimensions A, B, and C of the above portions are adjusted so that the relation A<B<C is satisfied when C is assumed. In the rice cooker 1, for example, if A>B, the lid 3 will not be closed because the flange 8g will not fit in the recess 4k. Also, in the rice cooker 1, for example, if B>C, the lid body 3 can be closed when the inner lid 8 is placed upside down on the engaging portion 4d. For example, since the lid body 3 cannot be closed when the inner lid 8 is placed upside down on the engaging portion 4d, it is possible to reliably prevent the inner lid 8 from being set in the wrong direction.

In the present embodiment, the rice cooker 1 (so-called electric rice cooker) in which an induction heating type heat source (so-called IH heater) is employed for the heating unit 6 has been described as an example. However, the rice cooker 1 using gas as a heating power source (a so-called gas rice cooker) may be configured to use the inner lid 8 and the inner pot 4 .

1 Rice Cooker 4 Inner Pot 4d Locking Part 4g Locking Surface 4h Opening 4k Recess 6 Heating Part 7 Inner Lid 8 Middle Lid 8a Horizontal Plate 8b Vertical Plate 8g Flange 8k Expanded Diameter 9 Controller CA Rice Cooking Space CA1 Small rice-cooking space CA2 Non-rice-cooking space d1 Inner diameter (of the opening)

Claims (4)

an inner pot having a bottom positioned at the lower end and an opening positioned at the upper end;
an inner lid that seals the opening of the inner pot;
a heating unit that heats the inner pot;
The rice-cooking space formed by the inner pot and the inner lid is divided into a small rice-cooking space that is in contact with the bottom and is a space for storing food to be cooked, and a space that is in contact with the inner lid and is located above the small rice-cooking space. A non-cooking space, an inner lid that divides into,
a locking portion projecting radially inward from an inner diameter of an opening of the inner pot at a position inside the rice cooking space of the inner pot and capable of locking the inner lid;
A rice cooker comprising
The inner pot is
A planar locking surface formed on the upper end of the locking portion and a recess formed between the opening and the locking portion by recessing radially outward from the inner diameter of the opening are formed,
the concave portion and the locking portion are continuous,
The locking surface is
expanded radially outward from the opening,
A rice cooker characterized by: Further comprising a control device for controlling the operation of the heating unit,
The heating unit
It includes a lid heater that heats the inner pot from above,
By said controller,
In the heat retention step after cooking rice using the inner lid,
Compared to the heat retention process after cooking rice without using the inner lid,
the heating amount of the lid heater is reduced;
The rice cooker according to claim 1, characterized by: The inner lid is
a disk-shaped horizontal plate;
a vertical plate portion surrounding the outer periphery of the horizontal plate portion;
a collar portion protruding radially outward from the vertical plate portion;
has
An enlarged diameter portion, which is formed by enlarging the vertical plate portion to have an outer diameter that substantially matches the inner diameter of the locking portion, is formed adjacent to the vertical plate portion and the collar portion,
The rice cooker according to claim 1 or 2, characterized by: The inner pot is made of ceramic,
The rice cooker according to any one of claims 1 to 3, characterized by:

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