JP7576752B2 - Rice cooker - Google Patents

Description

The present invention relates to a rice cooker.

A known conventional rice cooker is a fully automatic rice cooker that integrates a series of processes including rice storage, washing, and cooking. A conventional rice cooker includes 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 A

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

The object of the present invention is therefore to solve the above problems by providing a rice cooker equipped with a rice container for storing rice, which is capable of estimating 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 includes:
A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
and a capacitance detection unit provided on an 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. Cross-sectional view taken along line II-II in FIG. 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 an internal structure of the rice cooker according to the embodiment. FIG. 2 is a perspective view showing the rice container and a capacitance detection unit according to the embodiment. FIG. 2 is a perspective view showing the 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. 11 is a side view of the capacitance detection unit according to the embodiment, as viewed in a direction intersecting with the outer surface of the second side wall. FIG. 2 is a block diagram of the rice cooker according to the embodiment.

(Findings on which the present invention is based)
As a result of extensive research into estimating the amount of rice contained in a rice container, the present inventors have come 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 the rice container and estimate the amount of rice contained in the rice 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, and it is difficult to accurately estimate the amount of rice contained in the rice container using an optical sensor.

For example, a mechanical sensor could be installed in the rice container to estimate the amount of rice in the rice container. However, this method requires that the mechanical sensor come into contact with the rice in the rice container, and therefore the mechanical sensor needs to be installed inside the rice container. If a mechanical sensor is installed inside the rice container, it is difficult to keep the inside of the rice container hygienic, and if the mechanical sensor should fall off the rice container, there is a risk that the mechanical sensor will become a foreign object and become mixed into the rice container.

The inventors have therefore discovered a configuration in which the amount of rice contained in a rice container is detected by 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 rice container. Furthermore, the capacitance detection unit can detect the presence or absence of rice in the rice container even if it is provided on the outer surface of the rice container, so 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, the capacitance detection unit will not be mixed into the rice container as a foreign object. Based on these novel findings, the inventors have arrived at the following invention.

According to one aspect of the present invention,
A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to 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 position where the detection electrode is provided in the rice container can be detected by the change in capacitance of the detection electrode. This makes it possible to estimate the amount of rice contained in the rice container.

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

In addition, because the detection electrode is attached to the outer surface of the rice container, even if the detection electrode is peeled off from the rice container, it is possible to prevent the detection electrode from becoming mixed into the inside of the rice container.

The capacitance detection unit may include a plurality of the detection electrodes, which may be arranged in a row 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 is 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.

When the cross-sectional area perpendicular to the height direction of the rice container is formed to decrease from the top to the bottom of the rice container, if three or more detection electrodes are arranged in a row at equal intervals in the height direction of the rice container, the amount of rice contained between the detection electrodes decreases from the top to the bottom of the rice container, and rice cannot be detected at a constant amount. In contrast, with this configuration, three or more detection electrodes are arranged so that the intervals between the detection electrodes increase from the top to the bottom of the rice container, so the variation in the amount of rice contained between the detection electrodes can be reduced compared to when three or more detection electrodes are arranged in a row at equal intervals in the height direction of the rice container.

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

When 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 may vary depending on the distribution of the rice, and the presence or absence of rice at the height position of the rice container where the detection electrode is attached may not be detected accurately. In contrast, with this configuration, the horizontal dimension of the detection electrode is larger than the dimension of the detection electrode in the height direction of the rice container, so the presence or absence of rice can be detected by the detection electrode over a wider range in the horizontal direction compared to when the dimension of the detection electrode in the horizontal direction is smaller than the dimension of the detection electrode in the height direction of the rice container. Therefore, even if rice is unevenly distributed inside the rice container, it is possible to suppress a decrease in the accuracy of detecting the presence or absence of rice at the height position of 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 surrounding temperature, so the presence or absence of rice at the position of the rice container where the detection electrode is attached 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 located on the opposite side of the first side wall from the pot, so the detection electrode is less affected by heat generated when the pot is heated compared to when the detection electrode is attached to the first side wall. As a result, it is possible to suppress a decrease in the accuracy of detection of the presence or absence of rice at the position of the rice container where the detection electrode is attached.

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 thin-walled portion that is thinner than the adjacent portion, so the distance between the detection electrode and the rice is shorter than when the detection electrode is attached to the adjacent portion. 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, the rice container may include a thick portion that is thicker than the portion where the detection electrode is provided, and at least a portion of the wiring may be in contact with the outer surface of the thick portion.

The capacitance detected by the capacitance detection unit includes the capacitance formed between the detection electrode and the rice, as well as the parasitic capacitance formed between the rice and the wiring connected to the detection electrode. For this reason, if the parasitic capacitance increases, the accuracy of detecting the presence or absence of rice at the position where the detection electrode is attached may decrease. In contrast, with this configuration, at least a portion of the wiring is in contact with the outer surface of the thick-walled portion that is thicker than the portion where the detection electrode is provided, so the distance between the rice contained in the rice container and the wiring can be increased. This reduces the parasitic capacitance formed between the wiring and the rice, and suppresses a decrease in the accuracy of detecting the presence or absence of rice at the position where the detection electrode is attached in the rice container.

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

The capacitance of the detection electrode changes due to environmental factors such as the temperature around the detection electrode, so the presence or absence of rice at the position where the detection electrode is attached in the rice container may not be detected accurately. In contrast, in this configuration, the reference electrode is provided to face a part of the rice container that is different from the part where rice is stored, so the detection accuracy can be improved. More specifically, since the reference electrode is provided to face a part of the rice container that is different from the part where rice is stored, capacitance is less likely to occur between the rice stored in the rice container and the reference electrode compared to when the reference electrode is provided to face the part where rice is stored in the rice container. Therefore, by detecting the capacitance of the reference electrode, it is possible to detect the change in capacitance due to the influence of environmental factors (e.g., the temperature around the detection electrode and the reference electrode) that the detection electrode and the reference electrode are subjected to. Therefore, for example, by taking 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, it is possible to suppress a decrease in the detection accuracy of the presence or absence of rice at the position where the detection electrode is attached in the rice container.

The rice cooker may include an estimation unit that estimates the amount of remaining 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, and the estimation unit may estimate the amount of remaining rice based on the capacitance of the detection electrode, and 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 amount of remaining rice.

According to this configuration, by subtracting the supply amount set by the supply amount setting unit from the remaining amount of rice estimated based on the capacitance of the detection electrode, the remaining amount of rice 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, the estimation unit may estimate the remaining amount of rice based on the capacitance of the detection electrode when capacitance is formed between the rice contained in the rice container and the detection electrode.

The rice container has a 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 the water in 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. When the time measured by the timer unit exceeds a certain time, the control unit may control the water supply unit to supply an amount of water into the pot that is greater than the amount of water appropriate for the amount of rice to be cooked.

After rice is placed in the rice container, the rice may dry out (i.e., the moisture content of the rice may decrease) after a certain period of time. In this case, if the rice is cooked with an amount of water appropriate for the amount of rice to be cooked, the desired rice may not be cooked (for example, the rice may become harder than desired). Also, if the rice container lid is not opened or closed for a certain period of time, the rice stored in the rice container may dry out. With this configuration, when the rice container lid 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 into the pot, so that 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 has a lid for opening and closing the rice container inlet of the rice container, a water container for storing water, a water supply unit for supplying the water in the water container into the pot, a timer unit for measuring the time during which the rice container lid is not opened or closed, and a control unit for executing a soaking process, a temperature increase process, a boiling maintenance process, and a steaming process. When the time measured by the timer unit exceeds a certain time, the control unit may execute the soaking process for a time longer than the soaking time appropriate for the amount of rice to be cooked in the soaking process.

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 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 container 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 the water in the water container to the pot, a timer 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. When the time measured by the timer exceeds a certain time, the control unit may execute the soaking process at a temperature lower than the soaking temperature suitable for the amount of rice to be cooked in the soaking process.

Dry rice is prone to cracking, and when cracked rice is cooked, starch dissolves from the rice into the water during the soaking process, making the cooked rice sticky. As a result, it may not be possible to cook the desired rice. With this configuration, if the time during which the rice container lid is not opened or closed exceeds 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 to the pot from the rice container is dry and cracked, 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.

The cooking device includes a water container for storing water, a water supply unit for supplying the water in 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. When the time measured by the timing unit exceeds a certain period of time, the control unit may control the water supply unit to supply an amount of water into the pot that is greater than the amount of water 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, an amount of water greater than the amount of rice appropriate for the amount of rice to be cooked is supplied to the pot, so that 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 includes a water container for storing water, a water supply unit for supplying the water in 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. When the time measured by the timing unit exceeds a certain time, the control unit may execute the soaking process for a period of time longer than the soaking time 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 pot includes a water container for storing water, a water supply unit for supplying the water in the water container into the pot, a timer 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. When the time measured by the timer unit exceeds a certain period of time, the control unit may execute the soaking process at a temperature lower than the soaking temperature suitable for the amount of rice to be cooked in the soaking process.

According to 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 to be cooked. Therefore, even if the rice supplied to the pot from the rice container is dry and cracked, the starch is less likely to dissolve from the rice into the water during the soaking process, so the cooked rice is less sticky and the desired rice can be cooked.

The following describes an embodiment of the present invention with reference to the drawings. Note that the present invention is not limited to this embodiment. In addition, substantially identical components in the drawings are given the same reference numerals.

In addition, 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 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 pre-washed rice, is used as the rice to be cooked. Note that the rice to be cooked is not limited to pre-washed rice, and may be polished rice.

Referring to FIG. 1, the rice cooker 1 according to this embodiment includes a housing 10, a main body lid 11 that covers the upper part of the housing 10, and a rice storage section 20 that is disposed on the side of the housing 10 and that stores rice.

Referring to FIG. 2, the rice cooker 1 of this embodiment includes a bottomed, cylindrical pot 30. 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 includes 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 disposed inside the housing 10. More specifically, the heating unit 40 is disposed 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, the 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. 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 operation of the entire rice cooker 1.

Figure 3 is a perspective view of the rice cooker according to this embodiment with the rice container lid open. Also, 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 includes a rice container 70 for storing rice, a tube section 21, an outer cover 22, and a rice container lid 23.

The rice container 70 is box-shaped with rice stored 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 through 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. The rice supply pipe 80 is provided with a rice supply fan (not shown). 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 portion 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. This prevents the rice container 70 from being exposed to the outside. On the other hand, the outer cover 22 is located below the tube portion 21 and does not cover the tube portion 21. The material of the outer cover 22 is ABS resin. The relative dielectric constant of ABS resin is 2.4 to 4.1.

The rice container lid 23 is attached to a hinge portion 21a provided at the rear of the tube portion 21. The rice container lid 23 rotates around the hinge portion 21a to freely open and close the rice container inlet 70a (described later) 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 to 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 the relative dielectric constant of air (approximately 1.0) and lower than the relative dielectric constant of rice (3.5 to 3.7).

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

The rice container inlet 70a is provided at the upper 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 tube portion 21 (shown in Figure 3) are in communication with each other via the rice container inlet 70a.

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

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-rear direction Y. The front wall 71 extends along the lateral direction X and the vertical direction Z. The lateral direction X, the front-to-rear direction Y, and the height direction Z are mutually perpendicular.

The rear wall 72 constitutes the other side (rear side) of the rice container 70 in the front-rear direction Y, and is disposed at a distance from the front wall 71 in the front-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 disposed 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 range 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 range 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 constitutes one side of the rice container 70 in the horizontal direction X (the side facing the page in FIG. 6). The first side wall 73 extends along the front-rear direction Y and the up-down direction Z. The first side wall 73 is disposed opposite the housing 10 (shown in FIG. 2). More specifically, the first side wall 73 is disposed opposite the pot 30 (shown in FIG. 2) contained within the housing 10.

The second side wall 74 constitutes the other side of the rice container 70 in the horizontal direction X (the rear side of the paper in FIG. 6). The second side wall 74 extends along the front-rear direction Y and the up-down direction Z. The second side wall 74 is disposed at a distance from the first side wall 73 in the horizontal direction X. The second side wall 74 faces the first side wall 73 and is disposed on the opposite side of the pot 30 (shown in FIG. 2) from the first side wall 73. 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 attachment portion 75 to which a detection electrode 91 (described later) is attached, and ribs 76A and 76B. The first attachment portion 75 is disposed rearward of the center of the second side wall 74 in the front-to-rear direction, that is, closer to the rear wall 72. In the following description, when there is no need to distinguish between the ribs 76A and 76B, one of them may simply be referred to as rib 76.

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 inner space of the rice container 70). The outer surface of the first mounting portion 75 in this embodiment is a flat surface. The first mounting portion 75 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). Specifically, the thickness t1 of the first mounting portion 75 (dimension in the horizontal direction X in this embodiment) is 1.5 mm. The thickness t2 of the adjacent portion 74a (dimension in the horizontal direction X in this embodiment) is 2.3 mm. In addition, the thickness t3 of the portion where the rib 76 of the second side wall 74 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 from the outer surface of the second side wall 74 in the lateral direction X 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 disposed 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 disposed at the bottom of the internal space of the rice container 70. The rice transfer blade rotates by receiving a driving force from a motor. As a result, the rice contained in the internal space of the rice container 70 is supplied to the rice measuring section 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 transport blade. The storage section 77 is provided at the bottom of the rice container 70. The rice container outlet 70b is provided behind the storage section 77.

As shown in FIG. 5, the rice container 70 of this embodiment has a second attachment portion 78 to which a reference electrode 92, which will be described later, is attached. The second attachment portion 78 is a portion of the rice container 70 that is different from the portion in which rice is stored (specifically, the portion formed by the front wall 71, the rear wall 72, the first side wall 73, and the second side wall 74). The second attachment portion 78 is provided on the side of the storage portion 77 and below the second side wall 74 (more specifically, the first attachment portion 75). The second attachment 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-rear direction Y.

As shown in Figs. 5 and 6, the rice cooker 1 of this embodiment includes 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 simply be referred to as a detection electrode 91.

The detection electrode 91 is provided on the outer surface of the rice container 70 (shown in FIG. 5). More specifically, the detection electrode 91 is attached to the first mounting portion 75 (shown in FIG. 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.

The detection electrode 91 in this embodiment 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 the long side extends in the front-rear direction Y and the short side extends in the up-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-rear direction Y) is greater than the height dimension H of the detection electrode 91 (i.e., the up-down direction Z). In other words, the length of the long side of the detection electrode 91 is greater 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.

The detection electrodes 91A to 91E are arranged side by side at intervals in the height direction (i.e., the vertical direction Z). The detection electrodes 91A to 91E are also arranged to extend parallel to one another. More specifically, the detection electrodes 91A to 91E are arranged so that the intervals between the detection electrodes 91 (the heightwise distance between the detection electrodes 91) become wider from the top to the bottom of the rice container 70. Specifically, the interval S1 between the detection electrodes 91A and 91B is wider than the interval S2 between the detection electrodes 91B and 91C. The interval S2 between the detection electrodes 91B and 91C is wider than the interval S3 between the detection electrodes 91C and 91D. The interval S3 between the detection electrodes 91C and 91D is wider than the interval S4 between the detection electrodes 91D and 91E. These intervals are set so that the amount of rice contained between the detection electrodes 91 is about two cups (360 ml). In other words, the detection electrodes 91A-91E are positioned 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 FIG. 6), the horizontal dimension (front-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 FIG. 5). More specifically, the reference electrode 92 is attached to the second attachment portion 78 of the rice container 70. That is, the reference electrode 92 is attached to a portion of the rice container 70 that is different from the portion in which rice is contained. As a result, the reference electrode 92 does not form a capacitance with the rice contained in the rice container 70. That is, 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. That is, the reference electrode 92 may be attached to any position within a range in which the rice in the rice container 70 is not detected.

The detection electrodes 91A-91E and the sensor control unit 93 are connected to each other via wiring 94A-94E. The reference electrode 92 and the sensor control unit 93 are connected to each other via wiring 94F. In the following description, when there is no need to distinguish between the wirings 94A-94F, one of them 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, 76B (shown in FIG. 5). More specifically, the capacitance detection unit 90 is attached to the rice container 70 so that the portions of the wiring 94A-94F that extend in the height direction of the rice container 70 (shown by the two-dot chain line in FIG. 8) are positioned above the ribs 76A, 76B.

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

Referring to FIG. 9, the main body control unit 60 is electrically connected to the heating unit 40, the supply amount setting unit 61, the rice measuring unit 81, the opening/closing sensor 62 that detects the opening/closing of the rice container lid 23 (shown in FIG. 3), and the sensor control unit 93 of the capacitance detection unit 90. In addition, although not shown, the main body control unit 60 is electrically connected to the rice measuring unit 81 and the rice fan of the rice supply unit (more specifically, the rice supply pipe 80, the rice measuring unit 81, and the rice supply fan), and the water supply pump of the water supply unit (more specifically, the water supply pipe and the water supply 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 an input/output circuit, and software implemented in 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 increasing 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-absorbed by soaking it in water that is lower than the gelatinization temperature (e.g., 55 degrees) while the heating unit 40 heats the pot 30. The temperature increase 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 according to the amount of rice to be cooked input by the user through, 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 FIG. 4) to supply the amount of rice set by the supply amount setting unit 61 to the rice supply pipe 80.

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

The sensor control unit 93 is composed of hardware such as a computer and input/output circuits, and software implemented in 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 the wiring 94 (shown in FIG. 8). Depending on the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70, the capacitance of the corresponding detection electrode 91 changes. The sensor control unit 93 measures the change in capacitance of the detection electrode 91 based on the change in the measurement 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, the sensor control unit 93 of this embodiment detects the presence of rice at the position where the detection electrode 91 is attached in the rice container 70 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 value. 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 of 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 "no rice present" 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) from the detection result on 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 result for the detection electrodes 91A to 91E indicates "rice present", the estimation unit 60a estimates that 10 cups of rice are contained in the rice container 70. Also, when the detection result for the detection electrode 91A indicates "no rice" and the detection result for the detection electrodes 91B to 91E indicates "rice present", the estimation unit 60a estimates that 8 cups of rice are contained in the rice container 70. When the detection result for the detection electrodes 91A to 91B indicates "no rice" and the detection result for the detection electrodes 91C to 91E indicates "rice present", the estimation unit 60a estimates that 6 cups of rice are contained in the rice container 70. The estimation unit 60a estimates that four cups of rice are contained in the rice container 70 when the detection result for the detection electrodes 91A-91C indicates "no rice" and the detection result for the detection electrodes 91D-91E indicates "rice present." The estimation unit 60a estimates that two cups of rice are contained in the rice container 70 when the detection result for the detection electrodes 91A-91D indicates "no rice" and the detection result for the detection electrode 91E indicates "rice present."

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, an SSD (Solid State Drive), a magnetic storage device such as a hard disk, or other storage device alone or in an appropriate combination thereof. 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 retain the memory of the estimated remaining amount even if the power supply from an 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 FIG. 3) is not opened or closed. In other words, the timer measures the time that has elapsed since the opening/closing sensor 62 last detected that the rice container lid 23 was closed.

The timing unit of this embodiment also 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 "no rice present") for any of the detection electrodes 91A-91E. In yet other words, the timing unit measures the time that has elapsed 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.

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

In addition, when the detection result for the detection electrode 91E changes from "rice present" to "no rice", the estimation unit 60a of this embodiment newly estimates that two cups of rice are contained in the rice container 70. 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 to 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 estimates a new estimated remaining amount by subtracting the above 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 to 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 a larger amount of water than is appropriate for the amount of rice to be cooked into the pot 30 when the time during which the rice container lid 23 (shown in FIG. 3) has not been opened or closed as measured by the timer exceeds a certain period of time (e.g., 2 or 3 days). Here, the amount of water appropriate for the amount of rice to be cooked is an amount of water determined based on the amount of cooked rice and 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 execute the soaking process for a longer time than is appropriate for the amount of rice to be cooked in the soaking process when the time during which the rice container lid 23 (shown in FIG. 3) has not been opened or closed as measured by the timer 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 cooked rice, hardness, etc., input by the user via an input unit (not shown) or the like.

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 suitable for the amount of rice to be cooked in the soaking process 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 time (e.g., 2 or 3 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 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 suitable for the amount of rice to be cooked in the soaking process. Here, the soaking temperature suitable 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 and 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 when the time during which there is no change in the amount of rice detected by the detection electrode 91 measured by the timer exceeds 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 soaking time than is appropriate for the amount of rice to be cooked in the soaking process when the time during which there is no change in the amount of rice detected by the detection electrode 91 measured by the timer exceeds 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 suitable for the amount of rice to be cooked in the soaking process when the time during which there is no change in the amount of rice detected by the detection electrode 91 measured by the timer exceeds a certain period of time (e.g., 2 or 3 days). More specifically, the main body control unit 60 controls the heating unit 40 so that the temperature in the pot 30 is maintained at a temperature lower than the soaking temperature suitable for the amount of rice to be cooked in the soaking process when the time during which there is no change in the amount of rice detected by the detection electrode 91 measured by the timer exceeds a certain period of time.

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 the change in capacitance of the detection electrode 91. This makes it possible to estimate the amount of rice contained in the rice container 70.

In addition, because the change in capacitance of the detection electrode 91 can detect the presence or absence of rice at the position of the rice container 70 where the detection electrode 91 is attached in a non-contact manner, the inside of the rice container 70 can be kept hygienic, unlike when a contact-type sensor is used.

In addition, since the detection electrode 91 is attached to the outer surface of the rice container 70, even if the detection electrode 91 is peeled off from the rice container 70, the detection electrode 91 can be prevented from entering the inside 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), so that the presence or absence of rice can be detected at multiple positions in the height direction of the rice container 70. This allows the amount of rice contained in the rice container 70 to be estimated with even greater accuracy.

In the present embodiment, when the cross-sectional area perpendicular to the height direction of the rice container 70 is formed to decrease from the top to the bottom of the rice container 70, if the detection electrodes 91A-91E are arranged at equal intervals in the height direction 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 the present 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, so the variation in the amount of rice contained between the detection electrodes 91 can be reduced compared to the case where three or more detection electrodes 91 are arranged at equal intervals in the height direction of the rice container 70.

As shown in FIG. 6, when rice (indicated by reference symbol R in FIG. 6) is unevenly distributed inside the rice container 70, even if the same amount of rice is contained in the rice container 70, the capacitance of the detection electrode 91 varies depending on the distribution of the rice, and the presence or absence of rice at the height position where the detection electrode 91 is attached in the rice container 70 may not be detected accurately. In contrast, according to this embodiment, the dimension L of the detection electrode 91 in the horizontal direction (i.e., the front-back direction Y) is larger than the dimension H of the detection electrode 91 in the height direction (i.e., the up-down direction Z) of the rice container 70. Therefore, compared to the case where 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, the presence or absence of rice can be detected by the detection electrode 91 over a wide range in the horizontal direction. Therefore, even if rice is unevenly distributed inside the rice container 70, the decrease in the detection accuracy of the presence or absence of rice at the height position 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 surrounding temperature, so 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 located on the opposite side of the first side wall 73 from the pot 30, so the detection electrode 91 is less affected by the heat generated when the pot 30 is heated compared to when the detection electrode 91 is attached to the first side wall 73. As a result, it is possible to suppress a decrease in the accuracy of detection of 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 (e.g., the adjacent portion 74a or the portion of the second side wall 74 where the rib 76A is provided), and therefore the distance between the detection electrode 91 and the rice is shorter than 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 the capacitance formed between the detection electrode 91 and the rice, as well as the parasitic capacitance formed between the rice and the wiring 94 connected to the detection electrode 91 and the reference electrode 92. For this reason, if the parasitic capacitance increases, the accuracy of detection of the presence or absence of rice at the position where the detection electrode 91 is attached may decrease. In contrast, according to this embodiment, at least a part of the wiring 94 is in contact with the outer surface of the ribs 76A, 76B, which is thicker than the part where the detection electrode 91 is provided, so that the distance between the rice contained in the rice container 70 and the wiring 94 can be increased. This reduces the parasitic capacitance formed between the wiring 94 and the rice, and suppresses the decrease in the accuracy of detection of the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70.

In addition, 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-rear direction Y. Therefore, air exists 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 provided 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 of the rice container 70 where the detection electrode 91 is attached can be suppressed.

The capacitance of the detection electrode 91 changes under the influence of environmental factors such as the temperature around the detection electrode 91, so the presence or absence of rice at the position where the detection electrode 91 is attached in the rice container 70 may not be detected accurately. In contrast, in this configuration, the reference electrode 92 is provided to face the second attachment portion 78, which is a portion of the rice container 70 different from the portion where rice is contained, so that the detection accuracy can be improved. More specifically, since the reference electrode 92 is provided to face the second attachment portion 78, which is a portion of the rice container 70 different from the portion where rice is contained, capacitance is less likely to occur between the rice contained in the rice container 70 and the reference electrode 92, compared to when the reference electrode 92 is provided to face the portion of the rice container 70 where rice is contained. Therefore, by detecting the capacitance of the reference electrode 92, it is possible to detect the fluctuation in capacitance due to the influence of environmental factors (for example, the temperature around the detection electrode 91 and the reference electrode 92) to which the reference electrode 92 is subjected together with the detection electrode 91. For this reason, 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 suppress a decrease in the detection accuracy of the presence or absence of rice at the position of 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 stored in the rice container 70, the rice may dry out (i.e., the moisture content of the rice may decrease) after a certain period of time. In this case, if the rice is cooked with an amount of water appropriate for the amount of rice to be cooked, regardless of the dryness of the rice, the desired rice may not be cooked (for example, the rice may become harder than the desired hardness). In addition, if the time during which the rice container lid 23 is not opened or closed exceeds a certain period of time, the rice stored in the rice container 70 may be dry. According to this embodiment, when the time during which the rice container lid 23 is not opened or closed exceeds 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 into the pot 30, so that 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.

According to this embodiment, if the time during which the rice container lid 23 is not opened or closed exceeds a certain time, the soaking process is performed for a longer time than is appropriate for the amount of rice to be cooked in the soaking process, so that 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 when cracked rice is cooked, starch dissolves from the rice into the water during the soaking process, making the cooked rice sticky. As a result, it may not be possible to cook the desired rice. According to this embodiment, if the time during which the rice container lid 23 is not opened or closed exceeds 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, starch is less likely to dissolve from the rice into the water during the soaking process, so the cooked rice can be prevented from becoming sticky, and the desired rice can be cooked.

When 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, when 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.

According to 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 performed 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 70 to the pot 30 is dry. As a result, the desired rice can be cooked.

According to 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 in the soaking process. 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, so the cooked rice is less likely to become sticky, and the desired rice can be cooked.

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

Any of the various embodiments described above can be combined as appropriate to achieve the effects of each.

Although the present disclosure has been fully described in connection with the preferred embodiment with appropriate reference to the drawings, various modifications and alterations will be apparent to those skilled in the art. Such modifications and alterations 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 cover 20 Rice storage section 21 Tube section 21a Hinge section 22 Outer cover 23 Rice container cover 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 sending pipe 81 Rice measuring section 90 Capacitive detection section 91, 91A to 91E Detection electrode 92 Reference electrode 93 Sensor control section 94, 94A to 94F Wiring

Claims (16)

A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
a capacitance detection unit provided on the outer surface of the rice container and having a detection electrode that forms a capacitance with the rice contained in the rice container;
The rice container comprises:
The front wall and
a rear wall disposed at a distance from the front wall and having an inclined wall portion extending from the upper side of the rice container toward the lower side thereof so as to approach the front wall;
a side wall on which the detection electrode is attached, the side wall connecting the front wall and the rear wall;
Equipped with
A rice cooker wherein, when viewed from a direction intersecting the side wall to which the detection electrode is attached, the dimension of the detection electrode in a horizontal direction is greater than the dimension of the detection electrode in a height direction of the rice container. The capacitance detection unit includes a plurality of the detection electrodes,
The rice cooker according to claim 1 , wherein the plurality of detection electrodes are arranged side by side at intervals from each other in a height direction of the rice container. The rice container is formed so that a cross-sectional area perpendicular to a height direction becomes smaller from the top to the bottom of the rice container,
The rice cooker according to claim 2 , wherein the plurality of detection electrodes are three or more detection electrodes, and are arranged such that the intervals between the detection electrodes become wider from the top to the bottom of the rice container. The side wall 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 a thin-walled portion that is thinner than an adjacent portion,
The rice cooker according to claim 1 , wherein the detection electrode is attached to the thin portion. the capacitance detection unit includes a wiring connected to the detection electrode,
The rice container has a thick-walled portion that is thicker than a portion where the detection electrode is provided,
The rice cooker according to claim 1 , wherein at least a portion of the wiring is in contact with an outer surface of the thick portion. The capacitance detection unit includes a reference electrode,
The rice cooker according to claim 1 , wherein the reference electrode is provided so as to face a portion of the rice container other than a portion in which rice is contained. An estimation unit that estimates the amount of rice remaining in the rice container;
a supply amount setting unit that sets the supply 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 capacitance of the detection electrode, and then, when the supply amount is set by the supply amount setting unit, 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 for opening and closing 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 the capacitance of the detection electrode when the rice container lid is opened or closed. The rice cooker according to claim 8 or 9, wherein when the estimation unit determines that no capacitance is formed between the rice contained in the rice container and the detection electrode, it estimates the amount of remaining rice based on the capacitance of the detection electrode when capacitance is formed between the rice contained in the rice container and the detection electrode. A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
a capacitance detection unit provided on an outer surface of the rice container and having a detection electrode that forms a capacitance with the rice contained in the rice container;
A rice container lid for opening and closing the rice container inlet of the rice container;
A water container for storing 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;
A control unit that controls the amount of water supplied,
When the time measured by the timing unit exceeds a certain time, the control unit controls the water supply unit to supply an amount of water into the pot that is greater than the amount of water appropriate for the amount of rice to be cooked. A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
a capacitance detection unit provided on an outer surface of the rice container and having a detection electrode that forms a capacitance with the rice contained in the rice container;
A rice container lid for opening and closing the rice container inlet of the rice container;
A water container for storing 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 executes a submersion process, a temperature increase process, a boiling maintenance process, and a steaming process,
When the time measured by the timing unit exceeds a certain time, the control unit executes the soaking process for a longer period of time than is appropriate for the amount of rice to be cooked in the soaking process. A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
a capacitance detection unit provided on an outer surface of the rice container and having a detection electrode that forms a capacitance with the rice contained in the rice container;
A rice container lid for opening and closing the rice container inlet of the rice container;
A water container for storing 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 executes a submersion process, a temperature increase process, a boiling maintenance process, and a steaming process,
When the time measured by the timing unit exceeds a certain time, the control unit executes the soaking process at a temperature lower than a soaking temperature suitable for the amount of rice to be cooked in the soaking process. A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
a capacitance detection unit provided on an outer surface of the rice container and having a detection electrode that forms a capacitance with the rice contained in the rice container;
A water container for storing water;
a water supply unit that supplies water from the water container into the pot;
A timer that measures the time during which the amount of rice detected by the capacitance detection unit remains unchanged;
A control unit that controls the amount of water supplied,
When the time measured by the timing unit exceeds a certain time, the control unit controls the water supply unit to supply an amount of water into the pot that is greater than the amount of water appropriate for the amount of rice to be cooked. A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
a capacitance detection unit provided on an outer surface of the rice container and having a detection electrode that forms a capacitance with the rice contained in the rice container;
A water container for storing water;
a water supply unit that supplies water from the water container into the pot;
A timer that measures the time during which the amount of rice detected by the capacitance detection unit remains unchanged;
and a control unit that executes a submersion process, a temperature increase process, a boiling maintenance process, and a steaming process,
When the time measured by the timing unit exceeds a certain time, the control unit executes the soaking process for a longer period of time than is appropriate for the amount of rice to be cooked in the soaking process. A pot and
A housing for housing the pan;
A rice container for storing rice;
A rice supply unit that supplies rice from the rice container to the pot;
a capacitance detection unit provided on an outer surface of the rice container and having a detection electrode that forms a capacitance with the rice contained in the rice container;
A water container for storing water;
a water supply unit that supplies water from the water container into the pot;
A timer that measures the time during which the amount of rice detected by the capacitance detection unit remains unchanged;
and a control unit that executes a submersion process, a temperature increase process, a boiling maintenance process, and a steaming process,
When the time measured by the timing unit exceeds a certain time, the control unit executes the soaking process at a temperature lower than a soaking temperature suitable for the amount of rice to be cooked in the soaking process.

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