JP7788630B2 - rice cooker - Google Patents

Description

The present invention relates to a rice cooker.

A conventional rice cooker known is a fully automatic rice cooker that integrates the entire process of storing, washing, and cooking rice. Conventional rice cookers include a rice storage section for storing rice, a rice washing space for washing the rice, and a rice cooking section (see Patent Document 1).

JP 5-220047

With conventional rice cookers, it is not possible to know how much rice is stored in the rice storage compartment, making it impossible to determine how many cups of rice can be cooked, and there is room for improvement in terms of usability.

Therefore, the object of the present invention is to solve the above-mentioned problem by providing a rice cooker equipped with a rice container for storing rice, which can estimate the amount of rice contained in the rice container.

In order to achieve the above object, the present invention is configured as follows.
A rice cooker according to one aspect of the present invention comprises:
A pot and
A housing that houses the pot;
a rice container for storing rice;
a rice supply unit that supplies rice from the rice container into the pot;
and a capacitance detection unit provided on the outer surface of the rice container and having a detection electrode that forms capacitance with the rice contained in the rice container.

According to the present invention, in a rice cooker equipped with a rice container for storing rice, the amount of rice contained in the rice container can be estimated.

1 is a perspective view of a rice cooker according to an embodiment of the present invention; 2 is a cross-sectional view taken along line II-II in FIG. 1; FIG. 2 is a perspective view of the rice cooker according to the embodiment with the rice container lid open. FIG. 2 is a perspective view showing the internal structure of the rice cooker according to the embodiment. FIG. 2 is a perspective view showing a rice container and a capacitance detection unit according to the embodiment. FIG. 2 is a perspective view showing a rice container and a capacitance detection unit according to the embodiment. FIG. 7 is a perspective view showing a cross section taken along line VII-VII in FIG. 6; FIG. 10 is a side view of the capacitance detection unit according to the embodiment, viewed from a direction intersecting the outer surface of the second side wall. FIG. 2 is a block diagram of the rice cooker according to the embodiment.

(Findings that form the basis of the present invention)
The present inventors conducted extensive research to estimate the amount of rice contained in a rice container and came to the following findings.

The following methods can be used to estimate the amount of rice contained in a rice container.

For example, it is possible to install an optical sensor in a rice container and estimate the amount of rice contained in the container. However, with this method, the optical sensor will detect dirt (e.g., rice powder) adhering to the rice container, reducing the accuracy of estimating the amount of rice. In other words, there are problems specific to estimating the amount of rice, making it difficult to accurately estimate the amount of rice contained in a rice container using an optical sensor.

Another possibility is to install a mechanical sensor in a rice container to estimate the amount of rice inside. However, this method requires that the mechanical sensor come into contact with the rice inside the container, so the mechanical sensor must be installed inside the container. If a mechanical sensor is installed inside the container, it is difficult to keep the inside of the container hygienic, and if the mechanical sensor were to fall off, there is a risk that the mechanical sensor could become a foreign object and become mixed into the container.

The inventors therefore discovered a configuration in which the amount of rice contained in a rice container is detected using a capacitance detection unit. Compared to optical sensors, a capacitance detection unit (e.g., a capacitance sensor) can detect the presence or absence of rice in the rice container without being affected by dirt such as rice flour inside the container. Furthermore, since the capacitance detection unit can detect the presence or absence of rice even when installed on the outside surface of the rice container, it does not need to be installed inside the rice container. In other words, when a capacitance detection unit is used, the inside of the rice container can be kept hygienic, and even if the capacitance detection unit falls off the rice container, it will not become mixed in as a foreign object inside the rice container. Based on these new findings, the inventors arrived at the following invention.

According to one aspect of the present invention,
A pot and
A housing that houses the pot;
a rice container for storing rice;
a rice supply unit that supplies rice from the rice container into the pot;
and a capacitance detection unit provided on the outer surface of the rice container and having a detection electrode that forms capacitance with the rice contained in the rice container.

With this configuration, the presence or absence of rice at the location of the detection electrode in the rice container can be detected by changes in the capacitance of the detection electrode. This makes it possible to estimate the amount of rice contained in the rice container.

In addition, the presence or absence of rice at the location of the rice container where the detection electrode is attached can be detected non-contact by changes in the capacitance of the detection electrode, so unlike when using a contact-type sensor, the inside of the rice container can be kept hygienic.

In addition, because the detection electrode is attached to the outer surface of the rice container, even if the detection electrode is accidentally detached from the rice container, it can be prevented from entering the inside of the rice container.

The capacitance detection unit may include a plurality of detection electrodes, which may be arranged side by side at intervals in the height direction of the rice container.

With this configuration, multiple detection electrodes are arranged in a row in the height direction of the rice container, making it possible to detect the presence or absence of rice at multiple positions in the height direction of the rice container. This allows for even more accurate estimation of the amount of rice contained in the rice container.

The rice container may be formed so that the cross-sectional area perpendicular to the height direction decreases from the top to the bottom of the rice container, and the multiple detection electrodes may be three or more detection electrodes arranged so that the spacing between them increases from the top to the bottom of the rice container.

If the cross-sectional area of the rice container perpendicular to the height direction decreases from top to bottom, and three or more detection electrodes are arranged in a row at equal intervals along the height of the rice container, the amount of rice contained between the detection electrodes will decrease from top to bottom of the rice container, making it impossible to detect a consistent amount of rice. In contrast, with this configuration, three or more detection electrodes are arranged so that the intervals between them increase from top to bottom of the rice container, which reduces the variation in the amount of rice contained between the detection electrodes compared to when three or more detection electrodes are arranged in a row at equal intervals along the height of the rice container.

When viewed from a direction intersecting the outer surface on which the detection electrode is attached, the horizontal dimension of the detection electrode may be greater than the vertical dimension of the rice container.

If rice is unevenly distributed inside the rice container, even if the same amount of rice is contained inside the rice container, the capacitance of the detection electrode will vary depending on the distribution of the rice, and it may not be possible to accurately detect the presence or absence of rice at the height position in the rice container where the detection electrode is attached. In contrast, with this configuration, the horizontal dimension of the detection electrode is larger than the height position of the rice container, so the presence or absence of rice can be detected by the detection electrode over a wider horizontal range compared to when the horizontal dimension of the detection electrode is smaller than the height position of the rice container. Therefore, even if rice is unevenly distributed inside the rice container, it is possible to prevent a decrease in the accuracy of detecting the presence or absence of rice at the height position in the rice container where the detection electrode is attached.

The rice container may have a first side wall facing the pot and a second side wall facing the first side wall and located on the opposite side of the pot from the first side wall, and the detection electrode may be attached to the second side wall.

The capacitance of the detection electrode changes depending on the ambient temperature, so the presence or absence of rice at the location of the detection electrode in the rice container may not be accurately detected due to the influence of heat generated when the pot is heated. In contrast, with this configuration, the detection electrode is attached to the outer surface of the second side wall, which is located on the opposite side of the first side wall from the pot. Therefore, compared to when the detection electrode is attached to the first side wall, the detection electrode is less affected by the heat generated when the pot is heated. As a result, it is possible to prevent a decrease in the accuracy of detecting the presence or absence of rice at the location of the detection electrode in the rice container.

The rice container may have a thin-walled portion that is thinner than adjacent portions, and the detection electrode may be attached to the thin-walled portion.

The shorter the distance between the detection electrode and the object to be detected, the easier it is to detect the presence or absence of the object to be detected. With this configuration, the detection electrode is attached to a thinner section that is thinner than the adjacent section, so the distance between the detection electrode and the rice is shorter than when the detection electrode is attached to the adjacent section. As a result, the presence or absence of rice at the position in the rice container where the detection electrode is attached can be detected with high accuracy.

The capacitance detection unit may include wiring connected to the detection electrode, and the rice container may include a thick portion that is thicker than the portion where the detection electrode is provided, with at least a portion of the wiring contacting the outer surface of the thick portion.

The capacitance detected by the capacitance detection unit includes not only the capacitance formed between the detection electrode and the rice, but also the parasitic capacitance formed between the rice and the wiring connected to the detection electrode. Therefore, an increase in parasitic capacitance can reduce the accuracy of detecting the presence or absence of rice at the location where the detection electrode is attached. In contrast, with this configuration, at least a portion of the wiring is in contact with the outer surface of the thick-walled portion, which is thicker than the area where the detection electrode is attached, making it possible to increase the distance between the wiring and the rice contained in the rice container. This reduces the parasitic capacitance formed between the wiring and the rice, preventing a decrease in the accuracy of detecting the presence or absence of rice at the location where the detection electrode is attached in the rice container.

The capacitance detection unit may include a reference electrode, which may be arranged to face a portion of the rice container other than the portion in which rice is stored.

Because the capacitance of the detection electrode changes due to environmental factors such as the temperature surrounding the detection electrode, it may not be possible to accurately detect the presence or absence of rice at the location of the rice container where the detection electrode is attached. In contrast, with this configuration, the reference electrode is positioned facing a different part of the rice container from the part containing the rice, thereby improving detection accuracy. More specifically, because the reference electrode is positioned facing a different part of the rice container from the part containing the rice, capacitance is less likely to occur between the rice contained in the rice container and the reference electrode compared to when the reference electrode is positioned facing the part containing the rice. Therefore, by detecting the capacitance of the reference electrode, it is possible to detect fluctuations in capacitance due to the influence of environmental factors (e.g., the temperature surrounding the detection electrode and reference electrode) on both the detection electrode and the reference electrode. Therefore, for example, by calculating the difference between the capacitance of the detection electrode and the capacitance of the reference electrode, noise components due to environmental factors can be removed. As a result, a decrease in detection accuracy for the presence or absence of rice at the location of the detection electrode can be suppressed.

The rice cooker may include an estimation unit that estimates the remaining amount of rice contained in the rice container, and a supply amount setting unit that sets the amount of rice to be supplied from the rice container to the pot by the rice supply unit. The estimation unit may estimate the remaining amount of rice based on the capacitance of the detection electrode, and then, when the supply amount is set by the supply amount setting unit, estimate the amount of rice contained in the rice container by subtracting the supply amount set by the supply amount setting unit from the estimated remaining amount of rice.

With this configuration, by subtracting the supply amount set by the supply amount setting unit from the remaining rice amount estimated based on the capacitance of the detection electrode, the remaining rice amount can be continuously estimated even if the rice container contains an amount of rice that cannot be detected by the detection electrode.

The rice container may include a rice container lid that opens and closes the rice container inlet, and the estimation unit may estimate the remaining amount of rice based on the capacitance of the detection electrode when the rice container lid is opened or closed.

When the estimation unit determines that no capacitance is formed between the rice contained in the rice container and the detection electrode, it may estimate the remaining amount of rice based on the capacitance of the detection electrode when capacitance was formed between the rice contained in the rice container and the detection electrode.

The rice cooker includes a rice container lid that opens and closes the rice container inlet of the rice container, a water container that contains water, a water supply unit that supplies water from the water container into the pot, a timer that measures the time during which the rice container lid is not opened or closed, and a control unit that controls the amount of water supplied. If the time measured by the timer exceeds a certain period, the control unit may control the water supply unit to supply an amount of water into the pot that is greater than the amount appropriate for the amount of rice to be cooked.

After rice is placed in the rice container and a certain amount of time has passed, it may dry out (i.e., the moisture content of the rice may decrease). In this case, if the rice is cooked with an amount of water appropriate for the amount of rice to be cooked, it may not be possible to cook the desired rice (for example, the rice may become harder than desired). Furthermore, if the rice container lid is not opened or closed for a certain period of time, the rice placed in the rice container may have dried out. With this configuration, if the rice container lid is not opened or closed for a certain period of time, an amount of water greater than the amount appropriate for the amount of rice to be cooked is supplied to the pot. Therefore, even if the rice supplied from the rice container to the pot is dry, the rice can absorb a sufficient amount of moisture. As a result, the desired rice can be cooked.

The rice container cooking device comprises a rice container lid that opens and closes the rice container inlet of the rice container, a water container that contains water, a water supply unit that supplies water from the water container into the pot, a timing unit that measures the time during which the rice container lid is not opened or closed, and a control unit that executes a soaking process, a heating process, a boiling maintenance process, and a steaming process. If the time measured by the timing unit exceeds a certain time, the control unit may execute the soaking process for a longer time than is appropriate for the amount of rice to be cooked in the soaking process.

With this configuration, if the rice container lid has not been opened or closed for a certain period of time, the soaking process is carried out for a longer period of time than is appropriate for the amount of rice to be cooked. This allows the rice to absorb a sufficient amount of water even if the rice supplied from the rice container to the pot is dry. As a result, the desired rice can be cooked.

The rice cooker comprises a rice container lid that opens and closes the rice container inlet of the rice container, a water container that contains water, a water supply unit that supplies water from the water container into the pot, a timing unit that measures the time during which the rice container lid is not opened or closed, and a control unit that executes a soaking process, a heating process, a boiling maintenance process, and a steaming process. If the time measured by the timing unit exceeds a certain time, the control unit may execute the soaking process at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked in the soaking process.

Dry rice is prone to cracking, and if cracked rice is cooked, the starch dissolves from the rice into the water during the soaking process, making the cooked rice sticky. As a result, the rice may not be cooked to the desired consistency. With this configuration, if the rice container lid is not opened or closed for a certain period of time, the soaking process is carried out at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked. As a result, even if the rice supplied from the rice container to the pot is dry and cracked, the starch is less likely to dissolve from the rice into the water during the soaking process, preventing the cooked rice from becoming sticky and allowing the desired consistency to be cooked.

The rice cooker comprises a water container for storing water, a water supply unit for supplying the water from the water container into the pot, a timing unit for measuring the time during which the amount of rice detected by the capacitance detection unit remains unchanged, and a control unit for controlling the amount of water supplied. If the time measured by the timing unit exceeds a certain period, the control unit may control the water supply unit to supply an amount of water into the pot that is greater than the amount appropriate for the amount of rice to be cooked.

If the amount of rice detected by the capacitance detection unit remains unchanged for a certain period of time, the rice contained in the rice container may be dry. With this configuration, if the rice container lid is not opened or closed for a certain period of time, a larger amount of water than the amount of rice appropriate for the amount of rice to be cooked is supplied to the pot. Therefore, even if the rice supplied from the rice container to the pot is dry, the rice can absorb a sufficient amount of water. As a result, the desired rice can be cooked.

The cooking pot comprises a water container for storing water, a water supply unit for supplying water from the water container into the pot, a timing unit for measuring the time during which the amount of rice detected by the capacitance detection unit remains unchanged, and a control unit for executing a soaking process, a heating process, a boiling maintenance process, and a steaming process. If the time measured by the timing unit exceeds a certain period of time, the control unit may execute the soaking process for a period of time longer than that appropriate for the amount of rice to be cooked in the soaking process.

With this configuration, if the amount of rice detected by the capacitance detection unit remains unchanged for a certain period of time, the soaking process is carried out for a longer period of time than is appropriate for the amount of rice to be cooked. This allows the rice to absorb a sufficient amount of water even if the rice supplied from the rice container to the pot is dry. As a result, the desired rice can be cooked.

The cooking device comprises a water container for storing water, a water supply unit for supplying water from the water container into the pot, a timing unit for measuring the time during which the amount of rice detected by the capacitance detection unit remains unchanged, and a control unit for executing a soaking process, a heating process, a boiling maintenance process, and a steaming process. If the time measured by the timing unit exceeds a certain period of time, the control unit may execute the soaking process at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked in the soaking process.

With this configuration, if the amount of rice detected by the capacitance detection unit remains unchanged for a certain period of time, the soaking process is carried out at a temperature lower than the soaking temperature appropriate for the amount of rice being cooked. Therefore, even if the rice supplied from the rice container to the pot is dry and cracked, the starch is less likely to dissolve from the rice into the water during the soaking process, preventing the cooked rice from becoming sticky and allowing you to cook the rice to the desired consistency.

Embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to these embodiments. In addition, substantially identical components in the drawings are designated by the same reference numerals.

Furthermore, for the sake of convenience, the following uses terms indicating directions such as "upper," "lower," "front," and "rear," assuming normal use, but this is not intended to limit the use state of the rice cooker according to the present invention.

(Embodiment)
The overall configuration of a rice cooker according to one embodiment of the present invention will be described. FIG. 1 is a perspective view of the rice cooker according to this embodiment. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. The rice cooker 1 according to this embodiment is a so-called fully automatic rice cooker, which can automatically perform all processes from supplying rice and water to the pot to cooking the rice. Furthermore, in this embodiment, rice that does not need to be washed, so-called no-wash rice, is used as the rice to be cooked. Note that the rice to be cooked is not limited to no-wash rice, and may also be polished rice.

Referring to Figure 1, the rice cooker 1 according to this embodiment comprises a housing 10, a main body lid 11 that covers the top of the housing 10, and a rice storage compartment 20 that is located on the side of the housing 10 and that stores rice.

Referring to Figure 2, the rice cooker 1 of this embodiment includes a cylindrical pot 30 with a bottom. The pot 30 is housed within the housing 10. Rice is placed in the pot 30 during cooking.

A hinge portion 10a is provided at the upper rear portion of the housing 10. The main body lid 11 is attached to the hinge portion 10a. The main body lid 11 rotates around the hinge portion 10a to cover the opening of the pot 30 in an openable and closable manner.

The rice cooker 1 of this embodiment is equipped with a heating unit 40 that heats the pot 30. The heating unit 40 of this embodiment is an induction heating coil that inductively heats the pot 30 when electricity is applied. The heating unit 40 is located inside the housing 10. More specifically, the heating unit 40 is located within the housing 10 so as to face the bottom surface of the pot 30 and the lower part of the side surface of the pot 30.

The rice cooker 1 of this embodiment includes a water storage unit 50 that stores water. The water storage unit 50 is disposed inside the housing 10. The water storage unit 50 is in fluid communication with the inside of the pot 30 through a water supply pipe (not shown). The water supply pipe is provided with a water supply pump (not shown). When the water supply pump is driven, water in the water storage unit 50 is supplied into the pot 30 through the water supply pipe. The water storage unit 50 of this embodiment is an example of a water container according to the present invention. Furthermore, the water supply pipe and the water supply pump of this embodiment constitute an example of a water supply unit according to the present invention.

The rice cooker 1 of this embodiment is equipped with a main body control unit 60 that controls the overall operation of the rice cooker 1.

Figure 3 is a perspective view of the rice cooker according to this embodiment with the rice container lid open. Figure 4 is a perspective view showing the internal structure of the rice cooker according to this embodiment.

Referring to Figures 3 and 4, the rice storage section 20 comprises a rice container 70 for storing rice, a cylindrical section 21, an outer cover 22, and a rice container lid 23.

The rice container 70 is box-shaped and contains rice in its internal space. The height direction of the rice container 70 coincides with the vertical direction Z.

As shown in FIG. 4, the rice container 70 is in fluid communication with the inside of the pot 30 (shown in FIG. 2) through the rice supply pipe 80. The rice supply pipe 80 is connected to the rice container 70 via a rice measuring unit 81. The rice measuring unit 81 measures the amount of rice supplied from the rice container 70 and supplies the specified amount of rice to the rice supply pipe 80. A rice supply fan (not shown) is provided in the rice supply pipe 80. When the rice supply fan is driven, the rice supplied from the rice container 70 to the rice supply pipe 80 is supplied into the pot 30 through the rice supply pipe 80. The rice supply pipe 80, rice measuring unit 81, and rice supply fan of this embodiment constitute an example of a rice supply unit according to the present invention.

The cylindrical portion 21 is cylindrical and extends in the height direction of the rice container 70. The cylindrical portion 21 forms the upper part of the rice storage portion 20. The cylindrical portion 21 is attached to the upper end of the rice container 70.

The outer cover 22 covers the sides of the rice container 70, preventing the rice container 70 from being exposed to the outside. However, the outer cover 22 is located below the tubular portion 21 and does not cover it. The outer cover 22 is made of ABS resin, which has a relative dielectric constant of 2.4 to 4.1.

The rice container lid 23 is attached to a hinge 21a located at the rear of the tube 21. The rice container lid 23 rotates around the hinge 21a to freely open and close the rice container inlet 70a (described below) of the rice container 70.

Figure 5 is a perspective view showing a rice container and a capacitance detection unit according to this embodiment. Figure 6 is a perspective view showing a rice container and a capacitance detection unit according to this embodiment. Figure 5 is a perspective view of the rice container seen from the pot side, and Figure 6 is a perspective view of the rice container seen from the opposite side of the pot. Figure 7 is a perspective view showing a cross section taken along line VII-VII in Figure 6.

Referring to Figures 5 and 6, the rice container 70 is box-shaped and open at the top. The material of the rice container 70 in this embodiment is polypropylene. The relative dielectric constant of polypropylene is 2.0 to 2.6. In other words, the relative dielectric constant of the rice container 70 is higher than that of air (approximately 1.0) and lower than that of rice (3.5 to 3.7).

The rice container 70 has a rice container inlet 70a through which rice is introduced and a rice container outlet 70b for supplying rice to the rice measuring section 81 (shown in Figure 4).

The rice container inlet 70a is located at the top end of the rice container 70. The rice container inlet 70a is an opening that opens upward. The internal space of the rice container 70 and the internal space of the tubular portion 21 (shown in Figure 3) are in communication with each other via the rice container inlet 70a.

The rice container outlet 70b is located at the bottom end of the rice container 70. The rice container outlet 70b is an opening that opens toward the rear. The rice measuring unit 81 (shown in Figure 4) is connected to the rice container outlet 70b.

The rice container 70 has a front wall 71, a rear wall 72, a first side wall 73, and a second side wall 74. The front wall 71, the rear wall 72, the first side wall 73, and the second side wall 74 form the portion of the rice container 70 in which rice is stored.

The front wall 71 forms one side (front side) of the rice container 70 in the front-to-back direction Y. The front wall 71 extends along the lateral direction X and the vertical direction Z. The lateral direction X, the front-to-back direction Y, and the vertical direction Z are perpendicular to one another.

The rear wall 72 forms the other (rear) surface of the rice container 70 in the front-to-rear direction Y. The rear wall 72 is spaced apart from the front wall 71 in the front-to-rear direction Y. The rear wall 72 includes a vertical wall portion 72a and an inclined wall portion 72b that is connected to the lower end of the vertical wall portion 72a.

The vertical wall portion 72a extends along the horizontal direction X and the vertical direction Z. More specifically, the vertical wall portion 72a is arranged parallel to the front wall 71.

The inclined wall portion 72b extends downward at an angle so as to approach the front wall 71. As a result, in the area where the inclined wall portion 72b is provided, the cross-sectional area perpendicular to the height direction of the rice container 70 decreases from the top to the bottom of the rice container 70. In other words, in the area where the inclined wall portion 72b is provided, the volume per unit height of the rice container 70 decreases from the top to the bottom of the rice container 70.

The first side wall 73 forms one side of the rice container 70 in the lateral direction X (the side facing the page in Figure 6). The first side wall 73 extends along the front-to-back direction Y and the up-to-down direction Z. The first side wall 73 is positioned opposite the housing 10 (shown in Figure 2). More specifically, the first side wall 73 is positioned opposite the pot 30 (shown in Figure 2) housed within the housing 10.

The second side wall 74 forms the other side of the rice container 70 in the horizontal direction X (the far side of the page in Figure 6). The second side wall 74 extends along the front-to-rear direction Y and the up-down direction Z. The second side wall 74 is spaced apart from the first side wall 73 in the horizontal direction X. The second side wall 74 faces the first side wall 73 and is located on the opposite side of the first side wall 73 from the pot 30 (shown in Figure 2). In other words, the distance between the second side wall 74 and the pot 30 (more specifically, the distance in the horizontal direction X) is longer than the distance between the first side wall 73 and the pot 30 (more specifically, the distance in the horizontal direction X).

As shown in FIG. 5, the second side wall 74 is formed with a first mounting portion 75 to which a detection electrode 91 (described later) is attached, and ribs 76A and 76B. The first mounting portion 75 is located rearward of the center of the second side wall 74 in the fore-and-aft direction, i.e., closer to the rear wall 72. In the following description, when there is no need to specifically distinguish between the ribs 76A and 76B, one of them may be simply referred to as the rib 76.

As shown in FIG. 7 , the first mounting portion 75 is formed on the outer surface of the second side wall 74 so as to be recessed toward the first side wall 73 (i.e., toward the internal space of the rice container 70). In this embodiment, the outer surface of the first mounting portion 75 is flat. The first mounting portion 75 is thinner than the adjacent portion (e.g., the adjacent portion 74a or the portion of the second side wall 74 where the rib 76A is provided). Specifically, the thickness t1 of the first mounting portion 75 (in this embodiment, the dimension in the horizontal direction X) is 1.5 mm. The thickness t2 of the adjacent portion 74a (in this embodiment, the dimension in the horizontal direction X) is 2.3 mm. Furthermore, the thickness t3 of the portion of the second side wall 74 where the rib 76 is provided is 3.0 mm. The first mounting portion 75 in this embodiment is an example of a thin-walled portion according to the present invention.

The rib 76 protrudes in the lateral direction X from the outer surface of the second side wall 74 and extends in the vertical direction Z. The ribs 76A and 76B are spaced apart from each other in the front-to-rear direction Y. The rib 76A is located adjacent to the first mounting portion 75. The ribs 76A and 76B in this embodiment are an example of a thick portion according to the present invention. The height (dimension in the lateral direction X) of the rib 76 in this embodiment, i.e., the amount of protrusion D from the outer surface of the second side wall 74, is 0.7 mm.

Referring to Figures 5 and 6, a rice transfer blade (not shown) is located at the bottom of the internal space of the rice container 70. The rice transfer blade rotates when a driving force is transmitted from the motor. As a result, rice contained in the internal space of the rice container 70 is supplied to the rice measuring unit 81 (shown in Figure 4) via the rice container outlet 70b.

The rice container 70 of this embodiment has a roughly semi-cylindrical storage section 77 that houses the rice-transporting blade. The storage section 77 is located at the bottom of the rice container 70. The rice container outlet 70b is located behind the storage section 77.

As shown in FIG. 5, the rice container 70 of this embodiment has a second mounting portion 78 to which a reference electrode 92 (described later) is attached. The second mounting portion 78 is a different portion of the rice container 70 from the portion where rice is stored (specifically, the portion formed by the front wall 71, rear wall 72, first side wall 73, and second side wall 74). The second mounting portion 78 is provided to the side of the storage portion 77 and below the second side wall 74 (more specifically, the first mounting portion 75). The second mounting portion 78 of this embodiment consists of three ribs that protrude in the lateral direction X from the outer surface of the storage portion 77 and extend in the vertical direction Z. The three ribs are spaced apart from each other in the front-to-back direction Y.

As shown in Figures 5 and 6, the rice cooker 1 of this embodiment is equipped with a capacitance detection unit 90 attached to the rice container 70. The capacitance detection unit 90 of this embodiment is a capacitance-type sensor.

Figure 8 is a side view of the capacitance detection unit according to this embodiment, viewed from a direction intersecting the outer surface of the second side wall.

The capacitance detection unit 90 includes multiple (five in this embodiment) detection electrodes 91A-91E, a reference electrode 92, and a sensor control unit 93. In the following description, when there is no need to particularly distinguish between the five detection electrodes 91A-91E, one of the five detection electrodes 91A-91E may be simply referred to as the detection electrode 91.

The detection electrode 91 is provided on the outer surface of the rice container 70 (shown in Figure 5). More specifically, the detection electrode 91 is attached to the first mounting portion 75 (shown in Figure 5) of the second side wall 74. In other words, the detection electrode 91 is attached to the portion of the rice container 70 that contains rice. The detection electrode 91 forms a capacitance with the rice contained in the rice container 70.

In this embodiment, the detection electrode 91 is rectangular. The detection electrode 91 is attached to the second side wall 74 (shown in FIG. 6) of the rice container 70 so that its long sides extend in the front-to-rear direction Y and its short sides extend in the up-to-down direction Z. In this embodiment, when viewed from a direction intersecting the outer surface of the second side wall 74 (shown in FIG. 6), the horizontal dimension L of the detection electrode 91 (i.e., the front-to-rear direction Y) is greater than the height dimension H of the detection electrode 91 (i.e., the up-to-down direction Z). In other words, the length of the long side of the detection electrode 91 is longer than the length of the short side. The horizontal dimension L of the detection electrode 91 is, for example, 45 mm. The height dimension H of the detection electrode 91 is, for example, 5 mm.

Detection electrodes 91A-91E are arranged side by side at intervals in the height direction (i.e., the vertical direction Z). Furthermore, detection electrodes 91A-91E are arranged so that they extend parallel to one another. More specifically, detection electrodes 91A-91E are arranged so that the spacing between detection electrodes 91 (the heightwise distance between detection electrodes 91) increases from the top to the bottom of rice container 70. Specifically, spacing S1 between detection electrodes 91A and 91B is wider than spacing S2 between detection electrodes 91B and 91C. Spacing S2 between detection electrodes 91B and 91C is wider than spacing S3 between detection electrodes 91C and 91D. Spacing S3 between detection electrodes 91C and 91D is wider than spacing S4 between detection electrodes 91D and 91E. These spacings are set so that the amount of rice contained between detection electrodes 91 is approximately two cups (360 ml). In other words, the detection electrodes 91A-91E are arranged to detect the amount of rice contained in the rice container 70 every two cups.

The reference electrode 92 is square-shaped. When viewed from a direction intersecting the outer surface of the second side wall 74 (shown in Figure 6), the horizontal dimension (front-to-back direction Y) of the reference electrode 92 in this embodiment is equal to the height dimension (up-down direction Z) of the reference electrode 92. The area of the reference electrode 92 is equal to the area of the detection electrode 91.

The reference electrode 92 is attached to the outer surface of the rice container 70 (shown in Figure 5). More specifically, the reference electrode 92 is attached to the second attachment portion 78 of the rice container 70. In other words, the reference electrode 92 is attached to a portion of the rice container 70 that is different from the portion where rice is stored. This prevents the reference electrode 92 from forming capacitance with the rice stored in the rice container 70. In other words, the reference electrode 92 is positioned so as not to detect the rice in the rice container 70. The attachment position of the reference electrode 92 is not limited to this. In other words, the reference electrode 92 may be attached at any position within the range where it does not detect the rice in the rice container 70.

Detection electrodes 91A-91E and sensor control unit 93 are connected to each other via wiring 94A-94E. Reference electrode 92 and sensor control unit 93 are connected to each other via wiring 94F. In the following description, when there is no need to distinguish between wiring 94A-94F, one of these may simply be referred to as wiring 94.

In this embodiment, the capacitance detection unit 90 is positioned so that at least a portion of the wiring 94 is attached to the outer surfaces of the ribs 76A and 76B (shown in Figure 5). More specifically, the capacitance detection unit 90 is attached to the rice container 70 so that the portions of the wiring 94A-94F extending in the height direction of the rice container 70 (shown by the two-dot chain line in Figure 8) are positioned above the ribs 76A and 76B.

Figure 9 is a block diagram of the rice cooker 1 according to this embodiment.

Referring to Figure 9, the main body control unit 60 is electrically connected to the heating unit 40, supply amount setting unit 61, rice measuring unit 81, an opening/closing sensor 62 that detects the opening/closing of the rice container lid 23 (shown in Figure 3), and a sensor control unit 93 of the capacitance detection unit 90. Also, although not shown, the main body control unit 60 is electrically connected to the rice measuring unit 81 and the rice feeding fan of the rice supply unit (more specifically, the rice feeding pipe 80, rice measuring unit 81, and rice feeding fan), and the water feeding pump of the water supply unit (more specifically, the water feeding pipe and water feeding pump).

The main body control unit 60 controls the overall operation of the rice cooker 1. The main body control unit 60 is composed of hardware such as a computer and input/output circuits, and software implemented on the computer. The main body control unit 60 controls the heating unit 40 during rice cooking. The main body control unit 60 also controls the heating unit 40 to perform a soaking process, a temperature-raising process, a boiling maintenance process, and a steaming process. The main body control unit 60 of this embodiment is an example of a control unit according to the present invention.

The soaking process is a process in which the rice is pre-soaked in water that is lower than the gelatinization temperature (e.g., 55°C) while the heating unit 40 heats the pot 30, thereby allowing the rice to absorb water. The temperature-raising process is a process in which the heating unit 40 heats the pot 30 and brings the inside of the pot 30 to a boiling state. The boiling maintenance process is a process in which the heating unit 40 heats the pot 30 and maintains the boiling state inside the pot 30. The steaming process is a process in which the inside of the pot 30 is kept at a high temperature so that the rice gelatinizes all the way to the core.

The main body control unit 60 controls the rice measuring unit 81 and the rice supply fan to control the amount of rice supplied from the rice container 70 to the pot 30. The main body control unit 60 also controls the water supply pump to control the amount of water supplied from the water storage unit 50 to the pot 30.

The supply amount setting unit 61 sets the amount of rice to be supplied to the pot 30 during cooking, based on the amount of rice to be cooked input by the user via, for example, an input unit (not shown) such as a touch panel provided on the top surface of the main body lid 11 or an information terminal device such as a smartphone.

The main body control unit 60 controls the rice measuring unit 81 (shown in Figure 4) to supply the amount of rice set by the supply amount setting unit 61 to the rice delivery pipe 80.

The sensor control unit 93 is electrically connected to the detection electrodes 91A-91E and the reference electrode 92.

The sensor control unit 93 consists of hardware such as a computer and input/output circuits, and software implemented on the computer.

The sensor control unit 93 drives the detection electrode 91 and the reference electrode 92. More specifically, the sensor control unit 93 applies a measurement potential to the detection electrode 91 and the reference electrode 92 via wiring 94 (shown in FIG. 8). The capacitance of the corresponding detection electrode 91 changes depending on the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70. The sensor control unit 93 measures the change in capacitance of the detection electrode 91 based on the change in the measured potential of the detection electrode 91. The sensor control unit 93 detects the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70 (shown in FIG. 5) based on the change in capacitance of the detection electrode 91. Specifically, in this embodiment, the sensor control unit 93 detects the presence of rice at the position where the detection electrode 91 is attached when the difference between the capacitance of the detection electrode 91 and the capacitance of the reference electrode 92 is equal to or greater than a predetermined threshold. On the other hand, when the capacitance of the detection electrode 91 minus the capacitance of the reference electrode 92 is less than a predetermined threshold, it is detected that there is no rice at the position of the rice container 70 where the detection electrode 91 is attached. The predetermined threshold is, for example, the capacitance value of the detection electrode 91 when 50% of the area of the detection electrode 91 is in indirect contact with rice via the rice container 70. The sensor control unit 93 outputs the detection result regarding the presence or absence of rice at the position of the rice container 70 where the detection electrode 91 is attached to the main body control unit 60. More specifically, the sensor control unit 93 outputs the detection result of "rice present" or "rice absent" at the position of the rice container 70 where the detection electrode 91 is attached to the main body control unit 60.

The main body control unit 60 includes an estimation unit 60a, a memory unit 60b, and a timing unit (not shown).

The estimation unit 60a estimates the amount of rice contained in the rice container 70 (shown in FIG. 5) based on the detection results regarding the presence or absence of rice input from the sensor control unit 93 to the main body control unit 60. More specifically, when the detection results for detection electrodes 91A-91E indicate "rice present," the estimation unit 60a estimates that the rice container 70 contains 10 cups of rice. Furthermore, when the detection result for detection electrode 91A indicates "no rice" and the detection results for detection electrodes 91B-91E indicate "rice present," the estimation unit 60a estimates that the rice container 70 contains 8 cups of rice. When the detection result for detection electrodes 91A-91B indicates "no rice" and the detection results for detection electrodes 91C-91E indicate "rice present," the estimation unit 60a estimates that the rice container 70 contains 6 cups of rice. When the detection result for detection electrodes 91A-91C indicates "no rice" and the detection result for detection electrodes 91D-91E indicates "rice present," the estimation unit 60a estimates that four cups of rice are contained in the rice container 70. When the detection result for detection electrodes 91A-91D indicates "no rice" and the detection result for detection electrode 91E indicates "rice present," the estimation unit 60a estimates that two cups of rice are contained in the rice container 70.

The memory unit 60b is a recording medium that records various information, including programs and data necessary to realize the functions of the rice cooker 1. The memory unit 60b is realized, for example, by a semiconductor memory device such as a flash memory or an SSD (Solid State Drive), a magnetic storage device such as a hard disk, or other storage device, either alone or in combination as appropriate. The memory unit 60b stores the amount of rice contained in the rice container 70 estimated by the estimation unit 60a (hereinafter sometimes referred to as the estimated remaining amount). The memory unit 60b continues to store the estimated remaining amount even if the power supply from the external power source (not shown) to the rice cooker 1 is cut off.

In this embodiment, the timer measures the time during which the rice container lid 23 (shown in Figure 3) is not opened or closed. In other words, the timer measures the elapsed time since the opening/closing sensor 62 last detected that the rice container lid 23 was closed.

In addition, the timing unit of this embodiment measures the time during which there is no change in the amount of rice detected by the detection electrode 91. In other words, the timing unit measures the time during which there is no change in the detection result (i.e., "rice present" or "rice absent") for any of the detection electrodes 91A-91E. In yet other words, the timing unit measures the elapsed time since the last change in the detection result for any of the detection electrodes 91A-91E.

In this embodiment, the estimation unit 60a performs an update process to update the estimated remaining amount stored in the memory unit 60b.

In this embodiment, when the opening/closing sensor 62 detects that the rice container lid 23 has been closed, the estimation unit 60a newly estimates the amount of rice contained in the rice container 70 from the capacitance of the detection electrode 91. The estimation unit 60a then updates the estimated remaining amount stored in the memory unit 60b with the newly estimated remaining amount. In other words, the memory unit 60b stores the newly estimated remaining amount.

Furthermore, in this embodiment, when the detection result for the detection electrode 91E changes from "rice present" to "rice absent," the estimation unit 60a newly estimates that the rice container 70 contains two cups of rice. In other words, when the estimation unit 60a determines that no capacitance is formed between the rice contained in the rice container 70 and the detection electrode 91E, it newly estimates the estimated remaining amount based on the capacitance of the detection electrode 91 when capacitance was formed between the rice contained in the rice container 70 and the detection electrode 91E. The estimation unit 60a updates the estimated remaining amount stored in the memory unit 60b with the newly estimated estimated remaining amount. In other words, the memory unit 60b stores the newly estimated estimated remaining amount.

When the supply amount setting unit 61 sets the amount of rice to be supplied to the pot 30, the estimation unit 60a calculates a new estimated remaining amount by subtracting the supply amount from the estimated remaining amount stored in the memory unit 60b. The estimation unit 60a then updates the estimated remaining amount stored in the memory unit 60b with the newly estimated estimated remaining amount. In other words, the memory unit 60b stores the newly estimated estimated remaining amount.

In this embodiment, the main body control unit 60 controls the water supply unit (more specifically, the water pump) to supply more water than is appropriate for the amount of rice to be cooked into the pot 30 if the time measured by the timer unit during which the rice container lid 23 (shown in Figure 3) has not been opened or closed exceeds a certain period of time (e.g., two or three days). Here, the amount of water appropriate for the amount of rice to be cooked is determined based on the amount of rice to be cooked, the hardness of the rice, and other factors input by the user via an input unit (not shown) or the like.

Additionally or alternatively, the main body control unit 60 of this embodiment may execute the soaking process for a longer time than is appropriate for the amount of rice to be cooked if the time measured by the timer unit during which the rice container lid 23 (shown in FIG. 3) has not been opened or closed exceeds a certain period of time (e.g., 2 or 3 days). Here, the soaking time appropriate for the amount of rice to be cooked in the soaking process is a soaking time determined based on the amount of rice to be cooked, hardness, etc., input by the user via an input unit (not shown) or the like.

Additionally or alternatively, the main body control unit 60 of this embodiment may perform the soaking process at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked when the time measured by the timer during which the rice container lid 23 (shown in FIG. 3) has not been opened or closed exceeds a certain period of time (e.g., two or three days). More specifically, when the time measured by the timer during which the rice container lid 23 has not been opened or closed exceeds a certain period of time, the main body control unit 60 controls the heating unit 40 so that the temperature inside the pot 30 is maintained at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked. Here, the soaking temperature appropriate for the amount of rice to be cooked in the soaking process is a soaking temperature determined based on the amount of rice to be cooked, hardness, etc., input by the user via an input unit (not shown) or the like.

In addition, in this embodiment, the main body control unit 60 controls the water supply unit to supply an amount of water into the pot 30 that is greater than the amount of water appropriate for the amount of rice to be cooked if the amount of rice measured by the detection electrode 91 and measured by the timer unit remains unchanged for a certain period of time (e.g., 2 or 3 days).

Additionally or alternatively, the main body control unit 60 of this embodiment may execute the soaking process for a longer time than is appropriate for the amount of rice to be cooked if the amount of rice measured by the detection electrode 91 and measured by the timer does not change for a certain period of time (e.g., 2 or 3 days).

In addition, or alternatively, the main body control unit 60 of this embodiment may execute the soaking process at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked during the soaking process if the time period during which the amount of rice detected by the detection electrode 91 measured by the timer exceeds a certain period (e.g., two or three days). More specifically, if the time period during which the amount of rice detected by the detection electrode 91 measured by the timer exceeds a certain period, the main body control unit 60 controls the heating unit 40 so that the temperature inside the pot 30 during the soaking process is maintained at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked.

According to this embodiment, the presence or absence of rice at the position where the detection electrode 91 is provided in the rice container 70 can be detected by measuring changes in the capacitance of the detection electrode 91. This makes it possible to estimate the amount of rice contained in the rice container 70.

In addition, the presence or absence of rice at the location of the rice container 70 where the detection electrode 91 is attached can be detected non-contact based on changes in the capacitance of the detection electrode 91. Therefore, unlike when a contact-type sensor is used, the inside of the rice container 70 can be kept hygienic.

In addition, because the detection electrode 91 is attached to the outer surface of the rice container 70, even if the detection electrode 91 is accidentally detached from the rice container 70, the detection electrode 91 can be prevented from entering the interior of the rice container 70.

In this embodiment, the five detection electrodes 91A-91E are arranged in a row in the height direction of the rice container 70 (i.e., the vertical direction Z), making it possible to detect the presence or absence of rice at multiple positions in the height direction of the rice container 70. This allows for even more accurate estimation of the amount of rice contained in the rice container 70.

When the cross-sectional area of the rice container 70 perpendicular to the height direction is formed to decrease from the top to the bottom of the rice container 70, as in this embodiment, and the detection electrodes 91A-91E are arranged in a line at equal intervals along the height of the rice container 70, the amount of rice contained between the detection electrodes 91 decreases from the top to the bottom of the rice container 70, and rice cannot be detected at a constant amount. In contrast, according to this embodiment, the detection electrodes 91A-91E are arranged so that the intervals between the detection electrodes 91 become narrower from the top to the bottom of the rice container 70, which reduces the variation in the amount of rice contained between the detection electrodes 91 compared to when three or more detection electrodes 91 are arranged in a line at equal intervals along the height of the rice container 70.

As shown in FIG. 6 , if rice (denoted by reference symbol R in FIG. 6 ) is unevenly distributed inside the rice container 70, the capacitance of the detection electrode 91 may vary depending on the distribution of rice, even if the same amount of rice is contained inside the rice container 70. This may prevent accurate detection of the presence or absence of rice at the height where the detection electrode 91 is attached in the rice container 70. In contrast, according to this embodiment, the dimension L of the detection electrode 91 in the horizontal direction (i.e., the front-to-back direction Y) is greater than the dimension H of the detection electrode 91 in the height direction (i.e., the up-to-down direction Z) of the rice container 70. This allows the detection electrode 91 to detect the presence or absence of rice over a wider horizontal range than when the dimension of the detection electrode 91 in the horizontal direction is smaller than the dimension of the detection electrode 91 in the height direction of the rice container 70. Therefore, even if rice is unevenly distributed inside the rice container 70, a decrease in the accuracy of detecting the presence or absence of rice at the height where the detection electrode 91 is attached in the rice container 70 can be suppressed.

The capacitance of the detection electrode 91 changes depending on the ambient temperature, and the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70 may not be accurately detected due to the influence of heat generated when the pot 30 is heated. In contrast, according to this embodiment, the detection electrode 91 is attached to the outer surface of the second side wall 74, which is located on the opposite side of the first side wall 73 from the pot 30. Therefore, compared to when the detection electrode 91 is attached to the first side wall 73, the detection electrode 91 is less affected by the heat generated when the pot 30 is heated. As a result, it is possible to prevent a decrease in the accuracy of detecting the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70.

The shorter the distance between the detection electrode 91 and the object to be detected, the easier it is to detect the presence or absence of the object to be detected. According to this embodiment, the detection electrode 91 is attached to the first mounting portion 75, which is thinner than the adjacent portion (for example, the adjacent portion 74a or the portion of the second side wall 74 where the rib 76A is provided). This shortens the distance between the detection electrode 91 and the rice compared to when the detection electrode 91 is attached to the adjacent portion. As a result, the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70 can be detected with high accuracy.

The capacitance detected by the capacitance detection unit 90 includes not only the capacitance formed between the detection electrode 91 and the rice, but also the parasitic capacitance formed between the rice and the wiring 94 connected to the detection electrode 91 and reference electrode 92. Therefore, an increase in parasitic capacitance can reduce the accuracy of detecting the presence or absence of rice at the location where the detection electrode 91 is attached. In contrast, according to this embodiment, at least a portion of the wiring 94 is in contact with the outer surfaces of the ribs 76A, 76B, which are thicker than the portion where the detection electrode 91 is attached, thereby increasing the distance between the rice contained in the rice container 70 and the wiring 94. This reduces the parasitic capacitance formed between the wiring 94 and the rice, preventing a decrease in the accuracy of detecting the presence or absence of rice at the location where the detection electrode 91 is attached in the rice container 70.

Furthermore, in this embodiment, the thick portion according to the present invention is composed of ribs 76A, 76B spaced apart from each other in the front-to-rear direction Y. As a result, air is present in the space between the ribs 76A, 76B. This allows a layer of air with a lower dielectric constant than the dielectric constant of the rice container 70 to be formed between the portion of the wiring 94 attached to the ribs 76A, 76B and the rice contained in the rice container 70. As a result, the parasitic capacitance formed between the wiring 94 and the rice can be reduced, and a decrease in the detection accuracy of the presence or absence of rice at the position in the rice container 70 where the detection electrode 91 is attached can be suppressed.

Because the capacitance of the detection electrode 91 changes due to environmental factors such as the temperature surrounding the detection electrode 91, it may not be possible to accurately detect the presence or absence of rice at the location of the rice container 70 where the detection electrode 91 is attached. In contrast, with this configuration, the reference electrode 92 is positioned facing the second mounting portion 78, which is a portion of the rice container 70 different from the portion where rice is stored, thereby improving detection accuracy. More specifically, because the reference electrode 92 is positioned facing the second mounting portion 78, which is a portion of the rice container 70 different from the portion where rice is stored, capacitance is less likely to occur between the rice stored in the rice container 70 and the reference electrode 92, compared to when the reference electrode 92 is positioned facing the portion of the rice container 70 where rice is stored. Therefore, by detecting the capacitance of the reference electrode 92, fluctuations in capacitance due to environmental factors (e.g., the temperature surrounding the detection electrode 91 and reference electrode 92) that both the detection electrode 91 and the reference electrode 92 are exposed to can be detected. Therefore, for example, noise components due to environmental factors can be removed by calculating the difference between the capacitance of the detection electrode 91 and the capacitance of the reference electrode 92. As a result, it is possible to prevent a decrease in the accuracy of detecting the presence or absence of rice at the position in the rice container 70 where the detection electrode 91 is attached.

According to this embodiment, by subtracting the supply amount set by the supply amount setting unit 61 from the remaining rice amount estimated based on the capacitance of the detection electrode 91, the remaining rice amount can be continuously estimated even if the rice container 70 contains an amount of rice that cannot be detected by the detection electrode 91.

After rice is placed in the rice container 70 and a certain amount of time has passed, the rice may dry out (i.e., the moisture content of the rice may decrease). In this case, if the amount of water appropriate for the amount of rice to be cooked is used regardless of the rice's dryness, the desired rice may not be cooked (for example, the rice may become harder than desired). Furthermore, if the rice container lid 23 is not opened or closed for a certain period of time, the rice placed in the rice container 70 may dry out. According to this embodiment, if the rice container lid 23 is not opened or closed for a certain period of time, an amount of water greater than the amount of rice appropriate for the amount of rice to be cooked is supplied to the pot 30. Therefore, even if the rice supplied from the rice container 70 to the pot 30 is dry, the rice can absorb a sufficient amount of moisture. As a result, the desired rice can be cooked.

In this embodiment, if the rice container lid 23 is not opened or closed for a certain period of time, the soaking process is carried out for a longer period of time than is appropriate for the amount of rice to be cooked. Therefore, even if the rice supplied from the rice container 70 to the pot 30 is dry, the rice can absorb a sufficient amount of water. As a result, the desired rice can be cooked.

Dry rice is prone to cracking, and if cracked rice is cooked, the starch dissolves from the rice into the water during the soaking process, making the cooked rice sticky. As a result, the rice may not be cooked to the desired quality. According to this embodiment, if the rice container lid 23 is not opened or closed for a certain period of time, the soaking process is carried out at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked. Therefore, even if the rice supplied from the rice container 70 to the pot 30 is dry and cracked, the starch is less likely to dissolve from the rice into the water during the soaking process, preventing the cooked rice from becoming sticky and allowing the desired rice to be cooked.

If the amount of rice detected by the capacitance detection unit 90 remains unchanged for a certain period of time, the rice contained in the rice container 70 may be dry. According to this embodiment, if the rice container lid 23 is not opened or closed for a certain period of time, an amount of water greater than the amount of rice appropriate for the amount of rice to be cooked is supplied to the pot 30. Therefore, even if the rice supplied from the rice container 70 to the pot 30 is dry, the rice can absorb a sufficient amount of water. As a result, the desired rice can be cooked.

In this embodiment, if the amount of rice detected by the capacitance detection unit 90 remains unchanged for a certain period of time, the soaking process is carried out for a longer period of time than is appropriate for the amount of rice to be cooked. This allows the rice to absorb a sufficient amount of water even if it is dry when supplied from the rice container 70 to the pot 30. As a result, the desired rice can be cooked.

In this embodiment, if the amount of rice detected by the capacitance detection unit 90 remains unchanged for a certain period of time, the soaking process is carried out at a temperature lower than the soaking temperature appropriate for the amount of rice to be cooked. Therefore, even if the rice supplied from the rice container 70 to the pot 30 is dry and cracked, the starch is less likely to dissolve from the rice into the water during the soaking process, preventing the cooked rice from becoming sticky and allowing the desired rice to be cooked.

In this embodiment, the thick portions according to the present invention are the ribs 76A and 76B, but are not limited to this.

In addition, by appropriately combining any of the various embodiments described above, it is possible to achieve the effects of each.

While the present disclosure has been fully described in connection with preferred embodiments, with appropriate reference to the drawings, various variations and modifications will be apparent to those skilled in the art. Such variations and modifications are to be understood as included within the scope of the present invention as defined by the appended claims, unless they depart therefrom.

REFERENCE SIGNS LIST 1 Rice cooker 10 Housing 10a Hinge section 11 Main body lid 20 Rice storage section 21 Cylinder section 21a Hinge section 22 Outer cover 23 Rice container lid 30 Pot 40 Heating section 50 Water storage section 60 Main body control section 60a Estimation section 60b Memory section 61 Supply amount setting section 62 Opening/closing sensor 70 Rice container 70a Rice container inlet 70b Rice container outlet 71 Front wall 72 Rear wall 72a Vertical wall section 72b Inclined wall section 73 First side wall 74 Second side wall 75 First mounting section (thin section)
76, 76A, 76B Rib (thick part)
77 Storage section 78 Second mounting section 80 Rice conveying pipe 81 Rice measuring section 90 Capacitance detection section 91, 91A to 91E Detection electrode 92 Reference electrode 93 Sensor control section 94, 94A to 94F Wiring

Claims (10)

A pot and
A housing that houses the pot;
a rice container for storing rice;
a rice supply unit that supplies rice from the rice container into the pot;
a capacitance detection unit provided on the outer surface of the rice container,
The capacitance detection unit
a detection electrode that forms a capacitance with the rice contained in the rice container;
a reference electrode that forms a capacitance with a portion of the rice container other than the portion where rice is stored;
Wiring connected to the detection electrode;
Equipped with
the rice container includes at least one first rib disposed on an outer surface of the rice container;
At least a portion of the wiring is attached to an outer surface of the at least one first rib . the at least one first rib includes a plurality of first ribs spaced apart from one another;
The rice cooker according to claim 1 , wherein at least a portion of the wiring is attached to outer surfaces of the plurality of first ribs. The at least one first rib extends in a height direction of the rice container,
3. The rice cooker according to claim 1, wherein the capacitance detection unit is attached to the rice container so that a portion of the wiring extending in a height direction of the rice container is positioned on the at least one first rib. The rice cooker according to claim 1 , wherein the reference electrode is provided so as to face a portion of the rice container that is different from a portion in which rice is stored. The rice container is
a first side wall facing the pot;
a second side wall facing the first side wall and positioned on the opposite side of the pot with respect to the first side wall,
The rice cooker according to claim 1 , wherein the detection electrode is attached to the second side wall. The rice container has an attachment portion that is a portion of the rice container different from a portion in which rice is stored, the attachment portion being disposed on an outer surface of the rice container and having a plurality of second ribs that are spaced apart from one another;
The rice cooker according to claim 5 , wherein the reference electrode is attached to the attachment portion. The rice cooker according to claim 1 , wherein an area of the reference electrode is equal to an area of the detection electrode. an estimation unit that estimates the amount of rice remaining in the rice container;
a supply amount setting unit that sets the amount of rice to be supplied from the rice container to the pot by the rice supply unit,
8. The rice cooker according to claim 1, wherein the estimation unit estimates the remaining amount of rice based on the difference between the capacitance of the detection electrode and the capacitance of the reference electrode, and then, when the supply amount setting unit sets the supply amount, estimates the amount of rice contained in the rice container by subtracting the supply amount set by the supply amount setting unit from the estimated remaining amount of rice. A rice container lid is provided to open and close the rice container inlet of the rice container,
The rice cooker according to claim 8 , wherein the estimation unit estimates the remaining amount of rice based on a difference between the capacitance of the detection electrode and the capacitance of the reference electrode when the rice container lid is opened or closed. 10. The rice cooker according to claim 8, wherein when it is determined that no capacitance is formed between the rice contained in the rice container and the detection electrode, the estimation unit estimates the remaining amount of rice based on the difference between the capacitance of the detection electrode when capacitance is formed between the rice contained in the rice container and the detection electrode and the capacitance of the reference electrode.