Rice cooker

Abstract

To provide a rice cooker capable of determining an amount of rice to be cooked according to intended uses.SOLUTION: A rice cooker 2 includes a pot 25 for storing rice to be cooked, a heating coil 31 for heating the pot 25, a pot temperature sensor 46 for detecting the temperature of the pot 25, and a heating control circuit plate 42 for controlling the heating coil 31. The heating control circuit plate 42 changes the temperature of the pot 25 detected by the pot temperature sensor 46 by heating the pot 25 with the heating coil 31, and determines an amount of rice to be cooked on the basis of the change in the temperature with a plurality of determination methods.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a rice cooker. [Background technology]

[0002] A rice cooker is known that includes a pot that holds rice and water to be cooked, a heating coil that heats the pot, a rice cooking control unit that controls the heating coil, and a pot sensor that detects the temperature of the bottom of the pot. The heating coil includes a side coil and a bottom coil. The rice cooking control unit heats the pot without using the bottom coil, which is the heating coil located closest to the pot sensor, and determines the amount of rice to be cooked. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-136129 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional rice cookers control the side coil to heat the pot at a predetermined output for a predetermined first time, control the side coil to stop heating the pot for a predetermined second time after the first time has elapsed, and determine the amount of rice to be cooked based on the temperature of the pot after the second time has elapsed.

[0005] The determination of the amount of food to be cooked based on the temperature of the pot may be based only on the temperature of the pot at the end of the specified second hour, or may be based on the difference between the temperature of the pot at the end of the specified second hour and the temperature of the pot at the start of the specified first hour, or may be based on the difference between the temperature of the pot at the end of the specified second hour and the temperature of the pot at the end of the specified first hour when heating stops.

[0006] However, the method for determining the amount of food cooked by conventional rice cookers can be affected by factors such as the voltage, room temperature, and water temperature at the time of cooking. In other words, even if the same amount of food is placed in the pot, the determined amount can vary depending on factors such as the voltage applied to the rice cooker at the time of determination, the ambient temperature of the rice cooker, and the water temperature in the pot. For example, when the ambient temperature of the rice cooker is low, the accuracy of the determination decreases. Furthermore, the detection performance of a temperature sensor at low temperatures is generally lower than that at high temperatures.

[0007] Therefore, an object of the present invention is to provide a rice cooker that can further improve the accuracy of determining the amount of food being cooked. [Means for solving the problem]

[0008] In order to solve the above problems, a rice cooker according to an embodiment of the present invention comprises a pot that contains the food to be cooked, a heating unit that heats the pot, a temperature detection unit that detects the temperature of the pot, and a control unit that controls the heating unit, and the control unit executes a cooked rice amount determination process in which the heating unit heats the pot, thereby changing the temperature of the pot detected by the temperature detection unit, and determines the amount of the food to be cooked based on the change in temperature, and a preheating process in which the heating unit heats the pot before the cooked rice amount determination process, thereby increasing the initial temperature of the pot in the cooked rice amount determination process. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram of a rice cooking system according to an embodiment of the present invention. [Figure 2] 1 is a perspective view of a rice cooker according to an embodiment of the present invention; [Figure 3] 1 is a vertical cross-sectional view of a rice cooker according to an embodiment of the present invention. [Figure 4] FIG. 2 is a cross-sectional view of the inner frame and heating coil of the rice cooker according to the embodiment. [Figure 5] FIG. 2 is a bottom view of the inner frame and heating coil of the rice cooker according to the embodiment. [Figure 6] FIG. 2 is a control block diagram of the rice cooker according to the embodiment of the present invention. [Figure 7] 4A and 4B are diagrams showing the change in temperature in the pot over time and the change in output of the heating coil over time during the rice cooking operation of the rice cooker of this embodiment. [Figure 8] FIG. 2 is a diagram showing a first determination method as an example of a method for determining the amount of cooked rice in a rice cooker according to an embodiment of the present invention. [Figure 9] FIG. 10 is a diagram showing a second determination method as another example of a method for determining the amount of cooked rice in a rice cooker according to an embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing a second example of the first determination method for the rice cooker according to the embodiment of the present invention. [Figure 11] FIG. 10 is a diagram showing a second example of a second determination method for a rice cooker according to an embodiment of the present invention. [Figure 12] 1 is a front view of an example of an information terminal according to an embodiment of the present invention; [Figure 13] FIG. 1 is a block diagram of a smartphone as an example of an information terminal according to an embodiment of the present invention. [Figure 14] FIG. 3 is a diagram illustrating a first example of a first screen displayed on a display unit of an information terminal according to an embodiment of the present invention. [Figure 15] FIG. 10 is a diagram illustrating a second example of the first screen displayed on the display unit of the information terminal according to the embodiment of the present invention. [Figure 16] FIG. 10 is a diagram illustrating an example of a first sub-screen displayed on a display unit of an information terminal according to an embodiment of the present invention. [Figure 17] FIG. 10 is a diagram illustrating a first example of a second sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention. [Figure 18] FIG. 10 is a diagram illustrating a second example of a second sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention. [Figure 19] FIG. 10 is a diagram illustrating a third example of a second sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention. [Figure 20] FIG. 10 is a diagram illustrating a first example of a third sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention. [Figure 21] FIG. 10 is a diagram illustrating a second example of a third sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention. [Figure 22]FIG. 10 is a diagram illustrating a third example of a third sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] The rice cooking system, terminal device, program, and remaining rice amount display method according to the present invention will be described below with reference to Figures 1 to 22. Note that the same or corresponding components are denoted by the same reference numerals in the drawings.

[0011] FIG. 1 is a block diagram of a rice cooking system according to an embodiment of the present invention.

[0012] As shown in FIG. 1, a rice cooking system 1 according to an embodiment of the present invention provides information transmitted by a rice cooker 2 to an external device in a state in which the information terminal 3 can receive the information. The rice cooking system 1 may also provide information transmitted by the information terminal 3 to an external device in a state in which the rice cooker 2 in the home can receive the information. The information transmitted by the rice cooker 2 to an external device includes the current state and settings of the rice cooker 2. In other words, the rice cooking system 1 provides an environment in which the current state and settings of the rice cooker 2 in the home can be checked from the information terminal 3 while away from home, and an environment in which the rice cooker 2 in the home can be remotely controlled. For example, a user of the rice cooking system 1 can check the current state and settings of the rice cooker 2 while away from home, and operate the rice cooker 2 according to the current state and settings.

[0013] The rice cooking system 1 comprises a rice cooker 2 that cooks rice and water to cook the rice, and at least one information terminal 3 that is used to check the status of the rice cooking operation of the rice cooker 2 and to remotely control the rice cooker 2. The rice cooking system 1 only needs to include at least the rice cooker 2 and the information terminal 3. The rice cooker 2 and the information terminal 3 may establish a direct two-way communication environment using short-range wireless communication 5 such as NFC (Near Field Communication) or Bluetooth, or may establish a direct two-way communication environment via a home Wi-Fi network or the like.

[0014] The rice cooking system 1 may include a rice cooker 2, at least one information terminal 3, a server 7 that establishes communication between the rice cooker 2 and the information terminal 3, and a storage device 8 that stores information for establishing communication between the rice cooker 2 and the information terminal 3.

[0015] The rice cooker 2, information terminal 3, server 7, and storage device 8 are each communicatively connected to a network NW via a telecommunications network 11. The network NW may be, for example, the Internet, a cellular network, a Wi-Fi network, a low power wide area network (LPWA), a wide area network (WAN), a local area network (LAN), or other public or dedicated lines, depending on the situation.

[0016] The telecommunications network 11 includes a short-range wireless communication network 5, an external communication network 12, an in-house communication network 13, and a relay device 15 that relays information between the external communication network 12 and the in-house communication network 13.

[0017] The external communication network 12 includes a network NW. The repeater 15, server 7, and information terminal 3 are connected to the network NW via a public telephone network, a mobile phone network, etc. The rice cooking system 1 provides the user with a simple communication environment between the rice cooker 2 and the information terminal 3 by using the Internet as an intermediary.

[0018] The local area network 13 is a wireless or wired telecommunications network including a repeater 15, and is a so-called intranet.

[0019] The repeater 15 is, for example, at least one of a wireless router and a modem.

[0020] The rice cooker 2 is communicably connected to an in-house communication network 13. The rice cooker 2 can communicate with the server 7 via a repeater 15 installed in the user's residence.

[0021] The server 7 manages the rice cooker 2. The server 7 manages, for example, information relating to the device registration of the rice cooker 2, and information relating to the current state and settings of the rice cooker 2, including the status of the rice cooking operation of the rice cooker 2.

[0022] The server 7 also establishes a communication line via the network NW that allows two-way communication of information between the rice cooker 2 and the information terminal 3. The server 7 is, for example, a cloud server, and is composed of one or more server devices. The server 7 may also include an information processing unit that performs edge computing or fog computing, such as an information processing unit included in a router in the network NW. The server 7 is not limited to a cloud server, and may also be a computer in the user's residence, or a home router such as a wireless router.

[0023] The server 7 communicates with a large number of rice cookers 2 and a large number of information terminals 3 via the network NW. The server 7 assigns an identifier to each of the multiple rice cookers 2. The rice cooking system 1 establishes two-way communication between the information terminals 3 and the rice cookers 2 using the identifiers managed by the server 7.

[0024] For ease of explanation, "information related to rice cooker 2, including the device registration of rice cooker 2, the operating status of rice cooker 2, and the state of rice cooker 2" will be referred to as "rice cooker information" below.

[0025] The storage device 8 stores various types of information. The server 7 can refer to the information stored in the storage device 8. That is, the server 7 can receive the desired information in response to a specific request sent to the storage device 8. The information stored in the storage device 8 includes, for example, information sent from the rice cooker 2 and information sent from the information terminal 3.

[0026] The information terminal 3 is communicatively connected to at least one of the external communication network 12 and the local communication network 13. The information terminal 3 is a terminal device used by a user of the rice cooking system 1 to check the current status and current settings of the rice cooker 2 and to remotely control the rice cooker 2. The information terminal 3 may be a mobile terminal device such as a smartphone or tablet, or a terminal device that is not suitable for portability and is permanently installed in the home, such as a personal computer or smart speaker. The information terminal 3 communicates directly and bidirectionally with the rice cooker 2 via short-range wireless communication 5 or a repeater 15. The information terminal 3 is connected to the network NW via a public wireless line or a mobile phone line and can also communicate bidirectionally with the server 7. The information terminal 3 obtains information regarding the current status and current settings of the rice cooker 2 from the server 7 and outputs the current status and current settings of the rice cooker 2 on the screen of the information terminal 3.

[0027] An information terminal 3 such as a smartphone or tablet terminal device acquires information with or without the intervention of a server 7 and outputs the status of the rice cooker 2 on the screen of the information terminal 3. The information terminal 3 such as a smartphone or tablet terminal device also causes the linked rice cooker 2 to perform processing in response to user operations. When the smart speaker detects that a speaker has uttered a specific word, it uses this as a trigger to identify the speaker's subsequent questions and requests using natural language processing, converts a reaction or response according to the identified content into voice and outputs it, or causes the linked rice cooker 2 to perform processing according to the identified content. A similar natural language processing function may be installed in a portable information terminal 3 such as a smartphone, or in the rice cooker 2.

[0028] It is preferable that the information transmitted and received within the rice cooking system 1, including the rice cooker 2, information terminal 3, and server 7, is variable-length information with an amount of information appropriate to the needs. In other words, the information transmitted and received within the rice cooking system 1 may include all information regarding the current state and current settings of the rice cooker 2, or may include only a portion of the information regarding the current state of the rice cooker 2, or may include only a portion of the information regarding the current settings.

[0029] Furthermore, it is preferable that the rice cooker 2, information terminal 3, and server 7 share the current state and current settings of the rice cooker 2 without delay. Therefore, it is preferable that the rice cooker 2, information terminal 3, and server 7 mutually transmit and receive information indicating the current state and current settings of the rice cooker 2 at predetermined time intervals, for example, every five minutes. Therefore, the information terminal 3 and server 7 individually obtain information from the rice cooker 2 at predetermined time intervals and transmit the information to the rice cooker 2. It is sufficient that at least the rice cooker 2 and information terminal 3 share the current state and current settings of the rice cooker 2 without delay.

[0030] FIG. 2 is a perspective view of the rice cooker according to the embodiment of the present invention.

[0031] FIG. 3 is a vertical cross-sectional view of the rice cooker according to the embodiment of the present invention.

[0032] 2 is a perspective view of the rice cooker 2 according to this embodiment, seen from diagonally above the front right of the rice cooker 2. In other words, the front, right side, and top of the rice cooker 2 are visible in FIG. 2, while the back, left side, and bottom of the rice cooker 2 are hidden.

[0033] 2 and 3, rice cooker 2 according to this embodiment includes rectangular main body 23 having pot housing section 21 that opens upward, pot 25 housed in pot housing section 21, lid 26 that fits over the top of main body 23 to open and close pot housing section 21, hinge mechanism 27 that supports lid 26 on main body 23 so that it can be opened and closed, and power line 28 that can be connected to an external power source, such as a commercial AC power outlet. When lid 26 is opened upward on main body 23, pot 25 can be removed from pot housing section 21.

[0034] Rice cooker 2 heats and cooks rice and water contained in pot 25 using heating coil 31, and keeps the cooked rice (cooked rice) warm by heating it using heating coil 31. Rice cooker 2 cooks the food using a cooking course that is alternatively selected from a plurality of cooking courses.

[0035] Each cooking course has cooking conditions for cooking rice to rice. The cooking conditions include, for example, the type of rice, the cooking method for cooking the rice to rice, the hardness of the cooked rice, and the cooking time for cooking the rice to rice. Each cooking course includes at least two of these cooking conditions.

[0036] Each rice cooking course heats the food in pot 25 under a predetermined pressure. Each rice cooking course has processes that are set according to the brand of rice and the rice polishing ratio. Each process includes, for example, a soaking process that promotes the water absorption of rice placed in pot 25, a boiling and heating process that quickly raises the temperature of the food to the boiling point, a boiling continuation process that continues to boil the food, and a soaking process that maintains the temperature at a high enough temperature to prevent the rice from burning. Rice cooker 2 can also perform a warming process that keeps the rice in pot 25 at a predetermined warm temperature, either separately from the rice cooking course or consecutively to the rice cooking course.

[0037] Rice cooker 2 can also execute a cooking course that heats food other than the food placed in pot 25 using a predetermined heating pattern. Food includes the food to be cooked unless otherwise specified. Rice cooker 2 can also execute a maintenance course that boils water placed in pot 25 to use steam to lift dirt and remove odors from hard-to-clean parts inside rice cooker 2. For ease of explanation, the rice cooking course, cooking course, and maintenance course will hereinafter be collectively referred to simply as "courses."

[0038] Pot 25 is a container with a bottom that contains water and rice to be cooked. Pot 25 has a main body 25a made of aluminum, which has high thermal conductivity, and a heating element 25b that is joined to the main body from the lower outer periphery to cover the bottom. The heating element is made of a magnetic metal plate, such as ferritic stainless steel. Pot 25 has a flange 32 that protrudes radially outward and runs around the entire periphery.

[0039] The planar shape of main body 23 is rectangular. Main body 23 defines the front, back, left side, right side, and bottom of rice cooker 2 below lid 26. Main body 23 includes a bottom plate 35 that defines the bottom surface of main body 23, an upper frame 36 that covers the top of bottom plate 35 and defines part of the top surface and the side surfaces of main body 23, a bowl-shaped inner frame 37 that is integrally molded with upper frame 36, and an outer frame 38 that defines the remainder of the top surface of main body 23.

[0040] The bottom plate 35, upper frame 36, and outer frame 38 form the outer shell of the main body 23. The bottom plate 35 and upper frame 36 are molded from synthetic resin, such as polypropylene (PP). The outer frame 38 is molded from a metal material, such as stainless steel.

[0041] Upper frame 36 and inner frame 37 define pot accommodating section 21. Inner frame 37 corresponds to the bottom plate of pot accommodating section 21. Inner frame 37 is a molded product made of synthetic resin, for example, polyethylene terephthalate (PET).

[0042] Main body 23 also has control unit housing chamber 39 defined between the outer casing and pot housing section 21. The outer casing of main body 23 has vent hole 41 that directs outside air into control unit housing chamber 39. Vent hole 41 is preferably located on the bottom or side of main body 23.

[0043] Furthermore, the main body 23 is equipped with a heating control circuit board 42 housed in the control unit housing chamber 39. The heating control circuit board 42 is equipped with a microprocessor and a storage device that stores digital information such as various calculation programs executed by the microprocessor, parameters, etc. The storage device stores various settings (arguments) related to multiple preset courses.

[0044] The main body 23 also includes a heat sink 43 attached to the microprocessor of the heating control circuit board 42 and a cooling fan 45 for blowing air onto the heat sink 43 .

[0045] The heat sink 43 is made of a material with good thermal conductivity, such as aluminum. The cooling fan 45 is located below or to the side of the heat sink 43. The cooling performance of the combined heat sink 43 and cooling fan 45 is set to maintain the temperature of the microprocessor within the operating temperature range. The cooling fan 45 and the vent 41 of the main body 23 are preferably positioned so that they sandwich the pot 25. This positioning relationship contributes to the miniaturization of the product.

[0046] Furthermore, the main body 23 is provided with a heating coil 31 provided on the outer surface of the inner frame 37 and a pot temperature sensor 46 provided in the center of the bottom surface of the inner frame 37 to detect the temperature of the bottom of the pot 25.

[0047] Heating coil 31 is arranged to face the lower outer circumferential surface and bottom surface of pot 25 housed in pot housing section 21. Heating coil 31 generates an alternating magnetic field to heat heating element 25b of pot 25 by electromagnetic induction.

[0048] Pot temperature sensor 46 has a thermistor that detects the temperature of the bottom of pot 25. The temperature of the bottom of pot 25 will hereinafter be referred to as the "pot bottom temperature." Pot temperature sensor 46 is pressed against the bottom surface of pot 25 by spring force. The pot bottom temperature detected by pot temperature sensor 46 is used primarily to control the heating temperature of pot 25 by heating coil 31.

[0049] Hinge mechanism 27 includes hinge shaft 51 that swingably connects main body 23 and lid 26, and hinge spring 52 that applies a spring force to lid 26 so that lid 26, which closes pot housing section 21, opens upward on main body 23 around hinge shaft 51. Hinge shaft 51 is located near the upper part of the back surface of main body 23.

[0050] The planar shape of lid 26 is rectangular and covers main body 23. Lid 26 defines the front, back, left side, right side, and top of rice cooker 2 above main body 23. Lid 26 includes an outer lid 55 placed on the top of rice cooker 2, an outer lid cover 56 placed between outer lid 55 and main body 23, a metal heat sink 57 attached to outer lid cover 56, a lid heater 58 attached to heat sink 57, and an inner lid unit 59 detachably attached to outer lid cover 56 and detachably mounted below heat sink 57.

[0051] The inner lid unit 59 comprises a metal inner lid 61 that is positioned below the heat sink 57 and in contact with the heat sink 57, a lid gasket 62 that is provided on the outer periphery of the inner lid 61, and a gasket base 63 that integrates the inner lid 61 and the lid gasket 62.

[0052] Heat sink 57 and inner lid 61 are formed from anodized aluminum or stainless steel plate material. Inner lid 61 corresponds to the bottom surface of lid body 26. Inner lid 61 has a disk shape with substantially the same diameter as the upper opening of pot 25.

[0053] Lid gasket 62 is, for example, a molded product made of silicone rubber or fluororubber. Lid gasket 62 is a sealing material that seals the gap between pot 25 and inner lid 61 when lid 26 is closed. Lid gasket 62 comes into contact with the upper surface of flange 32 of pot 25 when lid 26 is closed.

[0054] When the lid body 26 to which the inner lid unit 59 is attached is closed, the lid gasket 62 is pressed against the upper surface of the flange portion 32 of the pot 25, and the inner lid unit 59 tightly covers the upper opening of the pot 25, sealing it so that steam generated when the pot 25 is heated does not leak from between the pot 25 and the inner lid unit 59.

[0055] The lid heater 58 is, for example, a cord heater. The lid heater 58 heats the heat sink 57, thereby heating the inner lid 61 that is in contact with the heat sink 57.

[0056] The lid 26 also has a steam outlet 65 that is removably attached to the rear half of the upper surface of the lid 26 and discharges steam generated from the food being cooked in the pot 25 to the outside of the rice cooker 2, a steam exhaust passage 66 that directs steam in the pot 25 to the steam outlet 65, and a pressure regulating valve 67 that allows or blocks the flow of gas in the steam exhaust passage 66.

[0057] The steam discharge passage 66 connects the steam port 65 and the pressure adjusting valve 67 .

[0058] Pressure regulating valve 67 is, for example, a solenoid valve. When pressure regulating valve 67 is opened, the inside of pot 25 is connected to the outside of rice cooker 2. At this time, pressure regulating valve 67 opens the inside of pot 25 to the atmosphere. Steam generated in pot 25 is released to the outside of rice cooker 2. When pressure regulating valve 67 is closed, the connection between the inside of pot 25 and the outside of rice cooker 2 is severed, restricting the flow of gas in and out through steam exhaust passage 66. At this time, pressure regulating valve 67 seals the inside of pot 25. Steam generated in pot 25 increases the internal pressure of pot 25 above atmospheric pressure. The internal pressure of pot 25 can also be reduced below atmospheric pressure by sucking out the gas inside pot 25 with pressure regulating valve 67 closed.

[0059] Pressure regulating valve 67 includes ball-shaped valve element 67a that allows or blocks the flow of gas through steam exhaust passage 66, and solenoid 67b that opens and closes valve element 67a. When steam in pot 25 is to be released to the outside of rice cooker 2, solenoid 67b rotates valve element 67a in one direction to open steam exhaust passage 66. When the internal pressure of pot 25 is to be increased or decreased, solenoid 67b rotates valve element 67a in the other direction to close steam exhaust passage 66. When the food to be cooked in pot 25 boils, generating steam, and this steam fills pot 25, causing the internal pressure of pot 25 to exceed a predetermined value, valve element 67a is pushed up by the internal pressure of pot 25 to open steam exhaust passage 66. When the internal pressure of pot 25 falls below the predetermined value, valve element 67a closes steam exhaust passage 66 under its own weight. Such operation of valve body 67a maintains the pressure inside pot 25 at or above atmospheric pressure.

[0060] Furthermore, the lid 26 is provided with a vacuum pump 68 that reduces the pressure inside the pot 25 when the lid 26 is closed.

[0061] The suction side of pressure reduction pump 68 is connected to pressure reduction hole 69 in inner lid 61. Pressure reduction pump 68 discharges gas from pot 25 through pressure reduction hole 69 to the outside of rice cooker 2, thereby reducing the internal pressure of pot 25. To reduce the internal pressure of pot 25, pot 25 is placed in pot housing portion 21, lid 26 is closed, and pressure adjustment valve 67 is closed. To restore the internal pressure of pot 25 from a reduced pressure state to atmospheric pressure, pressure reduction pump 68 is stopped and pressure adjustment valve 67 is opened. This connects the inside of pot 25 to the outside of rice cooker 2, allowing outside air to flow into pot 25. The passage connecting pressure reduction pump 68 and pressure reduction hole 69 may be equipped with an on-off valve that allows or blocks the flow of gas.

[0062] In other words, the pressure reducing pump 68 and the pressure adjusting valve 67 function as a pressure reducing section that can reduce the internal pressure of the pot 25 to a reduced pressure state lower than atmospheric pressure, and the pressure adjusting valve 67 also functions as a pressurizing section that can pressurize the internal pressure of the pot 25 to a pressurized state higher than atmospheric pressure.

[0063] The lid body 26 also includes a lid opening operation button 71 provided on the front half of the top surface of the lid body 26, a lid locking mechanism 72 that locks the opening and closing of the lid body 26, an operation panel 73 as an input / output device, and an input / output control circuit board 75 that controls the operation of the operation panel 73.

[0064] When lid-opening operation button 71 is operated, the lock between lid body 26, which closes pot accommodating section 21, and main body 23 is released. When lid body 26 and main body 23 are unlocked, the spring force of hinge spring 52 opens lid body 26 around hinge shaft 51 as the rotation center.

[0065] The lid locking mechanism 72 locks the lid 26 when the main body 23 is closed. The lid locking mechanism 72 unlocks the lid 26 in response to the operation of the lid-opening button 71. The lid locking mechanism 72 restricts the opening of the lid 26 even if the lid-opening button 71 is operated once if the internal pressure of the pot 25 is increased or decreased. If the lid-opening button 71 is operated again within a predetermined period of time, the lid locking mechanism 72 operates the pressure regulator valve 67 and the vacuum pump 68 to restore the internal pressure of the pot 25 to atmospheric pressure, and then releases the restriction on the opening of the lid 26. The lid locking operation of the lid locking mechanism 72 is controlled by the heating control circuit board 42. The detailed structure and control content of the lid locking mechanism 72 may be known technology, such as that described in JP 2015-171545 A. The lid locking operation of the lid locking mechanism 72 is not always performed. When the lid locking operation is not being performed, the lid 26 can be opened by operating the lid opening operation button 71 once.

[0066] The operation panel 73 includes a display unit 76 that displays various information, and an operation unit 77 that accepts various operations.

[0067] Display unit 76 is an output device that visually displays the current state of rice cooker 2. Display unit 76 is, for example, a display and a light-emitting diode (LED). The display is a liquid crystal display (LCD) panel or an organic electroluminescence (organic light-emitting diode) panel.

[0068] The display unit 76 includes multiple light-emitting diodes, including an LED that lights up the word "RESERVED" (Fig. 2) when a rice cooking operation has been scheduled and is on standby; an LED that lights up the word "KEEP WARM" (Fig. 2) when the food in the pot 25 is being kept warm; an LED that lights up the word "VACUUM" (Fig. 2) when the internal pressure of the pot 25 is reduced below atmospheric pressure; and an LED that lights up the word "PRESSURIZED" (Fig. 2) when the internal pressure of the pot 25 is increased above atmospheric pressure after the rice cooking operation. Therefore, even when the display is dimmed, the user can easily recognize the current status of the rice cooker 2. The light-emitting diodes may be the same color or different colors. The user can more easily recognize the current status of the rice cooker 2 by the difference in light-emitting colors. The display and the light-emitting diodes may be installed close to each other or far apart. The indications provided by these light-emitting diodes may be displayed on the display.

[0069] The operation unit 77 is an input device, a so-called touch sensor. The operation unit 77 is arranged directly above the display unit 76 so as to cover the display unit 76. The touch sensor has a plurality of key elements arranged on a plane. Each key element has a transparent electrode portion, for example, made of a conductive polymer, a contact portion connected to the input / output control circuit board 75, and pattern wiring connecting the transparent electrode portion and the contact portion. By pressing, touching, or bringing a fingertip against any of the display elements displayed on the display unit 76, the key element arranged directly above that display element is operated. The operation received by this key element is output to the input / output control circuit board 75 as a selection of the display element of the display unit 76 displayed directly below it.

[0070] The input / output control circuit board 75 is housed in the lid 26 and is located directly below the operation panel 73. The input / output control circuit board 75 is equipped with a microprocessor, a storage device that stores digital information such as various calculation programs and parameters executed by the microprocessor, and a real-time clock (RTC) with a timekeeping function. The storage device stores various settings (arguments) related to multiple preset courses. The real-time clock has a clock function that keeps track of the current time on the rice cooker 2 and a timekeeping function. The real-time clock may be located on either the heating control circuit board 42 or the input / output control circuit board 75.

[0071] A user of rice cooker 2 can select and input rice cooking conditions such as the type of rice, cooking method, hardness, and cooking time using operation unit 77. Based on the course set by operating operation unit 77, rice cooker 2 performs operations such as waiting for rice cooking, heating rice and water, keeping rice warm, and setting the rice cooking timer to standby.

[0072] It is assumed that a user of the rice cooker 2 will operate the operation panel 73 while standing in a position facing the front of the rice cooker 2. Therefore, the rice cooker 2 according to this embodiment is equipped with a lid-opening operation button 71 located in the front half of the top surface, closer to the user facing the front of the rice cooker 2, and a steam vent 65 located in the rear half of the top surface, farther from the user facing the front of the rice cooker 2. As a result, the rice cooker 2 according to this embodiment easily ensures a large space for arranging the display unit 76 between the lid-opening operation button 71 and the steam vent 65, and the size of the operation unit 77 located directly above the display unit 76 can be set as large as possible. Therefore, the rice cooker 2 can achieve high visibility of the display unit 76, high operability of the operation unit 77, and high safety against steam emitted from the steam vent 65.

[0073] Furthermore, the rice cooker 2 according to this embodiment does not have physical operation keys, such as a rice cooker key and an off key, as found in conventional rice cookers, and can be operated using only the operation unit 77. Therefore, the rice cooker 2 according to this embodiment eliminates the need to search for operation keys and provides intuitive operability. Furthermore, the rice cooker 2 without physical operation keys can improve space utilization efficiency by combining the display unit 76 and operation unit 77, making it easier to design a much sleek exterior compared to conventional rice cookers in which the input and output devices are separated. Furthermore, the top surface of the rice cooker 2, which does not have physical operation keys, can be made flat with almost no irregularities or gently curved. The top surface shape of this rice cooker 2 makes it easy to clean, such as by wiping.

[0074] FIG. 4 is a cross-sectional view of the inner frame and heating coil of the rice cooker according to this embodiment.

[0075] FIG. 5 is a bottom view of the inner frame and heating coil of the rice cooker according to this embodiment.

[0076] As shown in FIGS. 4 and 5, the heating coil 31 of the rice cooker 2 according to this embodiment includes a plurality of coils 11u and 11d.

[0077] First coil 31u is provided on the outer surface of inner frame 37, and second coil 31d is provided on the outer bottom surface of inner frame 37. First coil 31u faces the lower part of the outer surface of pot 25 across inner frame 37. Second coil 31d faces the outer bottom surface of pot 25 across inner frame 37.

[0078] The transfer of heat when the heating coil 31 is energized will be described.

[0079] When the first coil 31u is energized, the lower portion of the outer surface of the pot 25 first heats up, and the heat from this portion is conducted to the main material 25a of the pot 25 and transferred to the water contained in the food that is in contact with the lower portion of the inner surface of the pot 25. Heat transfer within the food occurs primarily through water movement, i.e., convection. Where rice is present in the food, water movement is limited to the narrow gaps between the rice grains, slowing the movement of water and heat. Where rice is not present, the movement of water and heat, i.e., convection, becomes active. Therefore, after the water in contact with the lower portion of the inner surface, the water in the upper portion of the food first heats up. Because the rice grains sink to the bottom of the pot 25 due to their own weight, the upper portion of the food contains almost no rice grains and essentially only water. Subsequently, in the center of the food, the water and heat from the upper portion, which has become hot, move to the middle portion of the food, which is still cooler, and then to the lower portion of the food. This phenomenon is so-called thermal convection, and is called "external convection" due to the first coil 31u.

[0080] Furthermore, when second coil 31d is energized, the outer surface of the bottom of pot 25 heats up first, and the heat from this area is conducted to main material 25a of pot 25 and transferred to the inner surface of the bottom of pot 25, i.e., the water contained in the lower portion of the food that is in contact with the bottom. Because the rice grains sink to the bottom of pot 25 due to their own weight, the bottom of the pot is covered with rice and water contained in the lower portion of the food. Therefore, the heat from the bottom of the pot increases the temperature and pressure of the water covering the bottom of the pot. Then, the water at the bottom of the pot, whose temperature and pressure have increased, moves upward through the gaps between the rice grains contained in the food. In other words, the water heated in the lower portion of the food, i.e., the hot water, moves together with the heat to the middle portion of the food, and then to the upper portion of the food. This phenomenon is known as "blowing up" and is called "internal convection" caused by second coil 31d.

[0081] When current is alternately applied to first coil 31u and second coil 31d, external convection and internal convection alternately occur in the food to be cooked in pot 25. In other words, when current is alternately applied to first coil 31u and second coil 31d, the alternating external and internal convection promotes stirring of the water contained in the food to be cooked in pot 25, thereby reducing uneven heating of the food to be cooked.

[0082] The heating control circuit board 42 of the rice cooker 2 according to this embodiment operates the heating coil 31 in a plurality of current patterns that are various combinations of the current conduction time of the first coil 31u, the current conduction time of the second coil 31d, the output of the first coil 31u, and the output of the second coil 31d. These multiple current conduction patterns are stored in the memory unit.

[0083] One type of energization pattern includes energizing the first coil 31u with a first output W1 and a first energization time T1, and then energizing the second coil 31d with a second output W2 and a second energization time T2. Each energization time T1 and T2 is preferably several seconds or longer. This allows external and internal convection to alternately occur in the food being cooked in the pot 25 for a predetermined period of time or longer. The alternating occurrence of external and internal convection promotes agitation of the water in the food being cooked in the pot 25 and reduces uneven heating.

[0084] It is preferable that the first current application time T1 and the second current application time T2 are different from each other. In other words, it is preferable that the time during which external convection occurs is different from the time during which internal convection occurs in a certain current application type.

[0085] The energization type may include one in which either the energization time or output of the heating coil 31 is varied while the other is kept constant. The energization time of each coil 31, 31d may be constant while the output of each coil 31, 31d may be different. Alternatively, the output of each coil 31, 31d may be constant while the energization time of each coil 31, 31d may be different.

[0086] The multiple energization patterns may include a de-energization period during which all of the heating coils 31 are de-energized. That is, the energization pattern is such that one of the two coils 31, 31d is energized for a predetermined energization time and with a predetermined output, and then, after a first de-energization period has elapsed, the other of the two coils 31, 31d is energized for a predetermined energization time and with a predetermined output, and then a second de-energization period is awaited. The first de-energization period and the second de-energization period may be the same or different.

[0087] The energization pattern may also include one in which current is intermittently applied to only one of the two coils 31, 31d, and no current is applied to the other of the two coils 31, 31d (no current is applied). Such an energization pattern applies current to one of the two coils 31, 31d for a predetermined current application time and at a predetermined current output, and does not apply current to both of the two coils 31, 31d for the predetermined current application time. Such an energization pattern is suitable for a heat retention process.

[0088] These current application patterns are repeated for a predetermined time or a predetermined number of times.

[0089] When the energization type is switched, the first energization type switches from energizing the first coil 31u with a first output W1 and a first energization time T1, and then energizing the second coil 31d with a second output W2 and a second energization time T2, to energizing the first coil 31u with a third output W3 and a third energization time T3, and then energizing the second coil 31d with a fourth output W4 and a fourth energization time T4. Each energization type is repeatedly executed for a predetermined time or a predetermined number of times before and after the switching.

[0090] The content of each energization type and the combination of multiple energization types are suitably set for each process included in the course.

[0091] In the energization type, the output of the first coil 31u and the output of the second coil 31d are adjusted by, for example, PWM control (Pulse Width Modulation).

[0092] FIG. 6 is a control block diagram of a rice cooker according to an embodiment of the present invention.

[0093] As shown in Figures 2 to 5 and Figure 6, the rice cooker 2 according to this embodiment operates in cooperation with the input / output control circuit board 75 and the heating control circuit board 42. The input / output control circuit board 75 and the heating control circuit board 42 input and output control signals in both directions. The input / output control circuit board 75 outputs a heating control signal to the heating control circuit board 42, and the heating control circuit board 42 outputs a display control signal to the input / output control circuit board 75.

[0094] The rice cooker 2 also includes a coil drive circuit 81 that supplies current to the heating coil 31, a lid heater drive circuit 83 that supplies current to the lid heater 58, a lid temperature sensor 85 that detects the temperature of the inner lid 61, a lid opening / closing sensor 86 that is provided inside the lid body 26 and detects the opening and closing of the lid body 26, a pressure sensor 87 that detects the internal pressure of the pot 25, an alarm unit 88, and a communication module 89 as a transmitter / receiver that establishes two-way communication between the rice cooker 2 and the information terminal 3.

[0095] The coil drive circuit 81 includes a first drive circuit 81u that applies a high-frequency current to the first coil 31u based on a first heating control signal output from the heating control circuit board 42, and a second drive circuit 81d that applies a high-frequency current to the second coil 31d based on a second heating control signal output from the heating control circuit board 42. The two coil drive circuits 81u and 81d are, for example, at least one of a power supply circuit, an inverter, an IH (Induction Heating) drive circuit, and a switching element. The coil drive circuit 81 increases or decreases the output of the two coils 11u and 11d by changing at least one of the period and the duty cycle of the high-frequency current applied to the two coils 11u and 11d.

[0096] For ease of explanation, it is assumed that the rice cooker 2 is equipped with a switching element that selectively selects whether to energize the two coils 11u and 11d. The rice cooker 2 may be capable of energizing the two coils 11u and 11d simultaneously. In other words, there may be a period during which the two coils 11u and 11d are energized simultaneously.

[0097] The lid heater drive circuit 83 applies DC or AC current to the lid heater 58 based on the lid heating control signal output from the heating control circuit board 42 .

[0098] The lid temperature sensor 85 is a thermistor. The lid temperature sensor 85 detects the temperature of the heat sink 57. The temperature detected by the lid temperature sensor 85, i.e., the temperature of the heat sink 57, correlates with the temperature of the inner lid 61. In other words, the temperature of the inner lid 61 can be inferred from the temperature detected by the lid temperature sensor 85. The temperature of the inner lid 61 inferred from the temperature detected by the lid temperature sensor 85 will hereinafter be referred to as the "lid temperature." The lid temperature detected by the lid temperature sensor 85 is used exclusively to manage the heating temperature of the inner lid 61 by the lid heater 58.

[0099] The lid opening / closing sensor 86 is preferably disposed near the hinge mechanism 27. The lid opening / closing sensor 86 may be a sensor of any detection type, such as an optical type, a mechanical type, or a magnetic type, as long as it can output a detection signal based on the opening or closing of the lid 26 to the input / output control circuit board 75. For example, when the lid 26 is open and tilted relative to the main body 23, the lid opening / closing sensor 86 detects the tilted position of the lid 26. Furthermore, for example, when the lid 26 is closed, the lid opening / closing sensor 86 detects the position of the lid 26.

[0100] Pressure sensor 87 is provided inside lid 26 and detects the pressure on the pot 25 side of pressure regulating valve 67 of steam exhaust passage 66, that is, the pressure equivalent to the internal pressure of pot 25, and outputs the result to heating control circuit board 42.

[0101] The notification unit 88 is at least one of the following: a light source that lights up or flashes, such as a lamp or a light-emitting diode (LED), which appeals to the visual sense of the user of the rice cooker 2; a sound device that emits an electrically synthesized voice or buzzer sound, which appeals to the auditory sense of the user of the rice cooker 2; or a vibrator, which appeals to the tactile sense of the user of the rice cooker 2.

[0102] The communication module 89 is built into the lid 26. The communication module 89 is a transmitter that transmits information from the rice cooker 2 to the information terminal 3, and a receiver that receives information transmitted by the information terminal 3. The communication module 89 is preferably capable of bidirectional communication with multiple information terminals 3 individually. In other words, the communication module 89 is preferably a transmitter that can transmit information from the rice cooker 2 to multiple information terminals 3 individually, and a receiver that can receive information transmitted individually by multiple information terminals 3. In other words, it is preferable that a single rice cooker 2 and multiple information terminals 3 are capable of bidirectional communication individually. In other words, it is preferable that the rice cooker 2 and multiple information terminals 3 are capable of bidirectional communication in a one-to-many relationship.

[0103] The information received by the communication module 89 from the information terminal 3 includes the setting conditions for each course that can be executed by the rice cooker 2. The information sent by the communication module 89 to the information terminal 3 includes the current state and current settings of the rice cooker 2. Of the information stored in the memory device of the heating control circuit board 42, the communication module 89 preferably sends at least the current state and current settings of the rice cooker 2 to the information terminal 3 and the server 7 at predetermined intervals.

[0104] The inputs to the input / output control circuit board 75 are operation signals output by the respective key elements of the operation unit 77 and display control signals output by the heating control circuit board 42. Based on these inputs, the input / output control circuit board 75 controls the display operation of the display unit 76, controls the operation of the notification unit 88, and outputs a heating control signal to the heating control circuit board 42.

[0105] The microprocessor of the input / output control circuit board 75 executes a predetermined program to function as an input signal generation unit 92 that generates control signals corresponding to the operation signals output by each key element, a display control unit 93 that controls the display operation of the display unit 76, and a condition setting unit 95 that works in conjunction with the input signal generation unit 92 and the display control unit 93 to enable the presentation, selection, and setting of various conditions that can be selected by the key elements.

[0106] The condition setting unit 95 sequentially presents a plurality of courses including, for example, a cooking course, a rice cooking course, and a maintenance course, and allows the user to select and set a desired course.

[0107] The memory device of the input / output control circuit board 75 stores rice cooking courses corresponding to various conditions that can be selected using key elements, such as rice brand, cooking method, hardness, etc. The display unit 76 displays the various conditions of the courses stored in the memory device, and by accepting operations to select these conditions using the operation unit 77, the course can be selected and set appropriately.

[0108] The heating control circuit board 42 of the main body 23 controls the temperature of the pot 25 and the temperature of the inner lid 61 by adjusting the heating coil 31 and the lid heater 58 during cooking and keeping the rice warm, based on the pot bottom temperature detected by the pot temperature sensor 46 and the lid temperature detected by the lid temperature sensor 85.

[0109] The inputs to the heating control circuit board 42 are the temperature detection signal output by the pot temperature sensor 46, the temperature detection signal output by the lid temperature sensor 85, the internal pressure detection signal output by the pressure sensor 87, the lid open / close detection signal output by the lid open / close sensor 86, and the heating control signal output by the input / output control circuit board 75.

[0110] Based on these inputs, heating control circuit board 42 controls heating coil 31, which heats pot 25 during rice cooking and keeping warm, and lid heater 58, which heats inner lid 61. Heating control circuit board 42 controls the temperature of the bottom of pot 25 mainly by controlling heating coil 31 based on the temperature detection signal output by pot temperature sensor 46. Heating control circuit board 42 controls the temperature of inner lid 61 mainly by controlling lid heater 58 based on the temperature detection signal output by lid temperature sensor 85.

[0111] In addition, the heating control circuit board 42 controls the opening and closing operation of the pressure regulating valve 67 in the steam exhaust passage 66, the decompression operation of the decompression pump 68, and the lid locking operation of the lid locking mechanism 72 based on the internal pressure detection signal output by the pressure sensor 87.

[0112] The microprocessor of the heating control circuit board 42 functions as a rice cooking control unit 97 and a keep-warm control unit 98 by executing a predetermined program.

[0113] When a command to start cooking is input to the operation unit 77, the rice cooking control unit 97 performs the rice cooking operation by sequentially executing a soaking cooking process, a boiling heating process, a continuing boiling process, and a steaming process. Also, when a command to start cooking is input to the operation unit 77, the rice cooking control unit 97 sequentially executes the cooking processes.

[0114] The heat retention control unit 98 executes a heat retention process, which includes a simple heat retention process for keeping the rice in the pot 25 at a predetermined heat retention temperature, and a reheating heat retention process for reheating rice in the pot 25 that is lower than the predetermined heat retention temperature, to the predetermined heat retention temperature.

[0115] The memory device of the heating control circuit board 42 stores pressurization / depressurization types that combine various drive timings for the pressure regulating valve 67 and the pressure reducing pump 68, as well as current supply types for the first coil 31u and the second coil 31d, and combinations of their execution timings for each course.

[0116] The states of the rice cooker 2 include, for example, "standby," in which the rice is waiting without performing any process, "adding soaking," in which the rice is soaked in extra water, "cooking," in which the rice and water are cooked to make rice, "keeping warm," in which the temperature of the rice is maintained, and "reserving cooking," in which the rice is waiting to start cooking at a predetermined set time. Any of the states currently being executed by the rice cooker 2, namely, "standby," "adding soaking," "cooking," "keeping warm," and "reserving cooking," are included in the current state of the rice cooker 2.

[0117] Next, an example of the rice cooking course executed by the rice cooker 2, that is, the rice cooking operation, will be described.

[0118] The food to be cooked is placed in pot 25. Next, pot 25 containing the food to be cooked is placed in pot accommodating section 21 of main body 23, and lid 26 is closed.

[0119] When the rice cooker 2's power plug is inserted into a commercial AC power outlet, the rice cooker 2 starts up in an initial state in which it is not cooking rice or keeping it warm. This initial state is also called a standby state or a stopped state. After the rice cooker 2 starts up, the communication module 89 of the rice cooker 2 preferably establishes communication with the telecommunications network 11 and transmits and receives information indicating the current state and settings of the rice cooker 2 at predetermined time intervals, for example, every five minutes.

[0120] In the initial state, each time a key element of the operation unit 77 is operated, an operation signal corresponding to the operated key element is input to the input signal generation unit 92. The condition setting unit 95 works in cooperation with the input signal generation unit 92 to change the rice cooking course setting, and works in cooperation with the display control unit 93 to display the changed setting on the display unit 76. The display unit 76 visually presents the current rice cooking course setting corresponding to the operated key element to the user of the rice cooker 2.

[0121] When a key element corresponding to the selection of the rice cooking course is operated, an operation signal corresponding to the selection of the rice cooking course is input to the input signal generation unit 92. The condition setting unit 95 stores the rice cooking course displayed on the display unit 76 in a storage device, and outputs a heating pattern corresponding to the selected rice cooking course to the heating control circuit board 42.

[0122] FIG. 7 is a diagram showing the change over time in the temperature inside the pot and the change over time in the output of the heating coil during the rice cooking operation of the rice cooker of this embodiment.

[0123] 7 shows the time variation of the pan temperature Ti and the time variation of the output P of heating coil 31. For ease of explanation, the output P of heating coil 31 is simplified by treating the two coils 11u and 11d as a single coil. For ease of explanation, the pan temperature Ti is assumed to be the pan bottom temperature detected by pan temperature sensor 46.

[0124] As shown in Figure 7, the rice cooking control unit 97 of the rice cooker 2 according to this embodiment performs rice cooking operations including a soaking cooking process, a boiling heating process, a continued boiling process, and a steaming process according to the heating pattern corresponding to the selected rice cooking course, to cook the food to be cooked until it is cooked rice. The control that executes each process is called by the name of the process. For example, the control that executes the soaking cooking process is called soaking cooking control.

[0125] The soaking process includes a preheating process, a cooking amount determination process for determining the amount of cooked rice, and a soaking process for promoting water absorption by the rice contained in the food to be cooked. Note that the entire soaking process is sometimes called the soaking process in a broad sense, and the soaking process within the soaking process is sometimes called the soaking process in a narrow sense.

[0126] When the soaking process starts, the rice cooking control unit 97 temporarily reduces the internal pressure of the pot 25, restores it to atmospheric pressure, and then operates the pressure reducing pump 68 and pressure adjusting valve 67 to restore the reduced pressure again.

[0127] First, the rice cooking control unit 97 operates the solenoid 67b to close the steam exhaust passage 66 with the pressure regulating valve 67, allowing gas to flow through the path connecting the inside of the pot 25 and the vacuum pump 68, and operates the vacuum pump 68 to remove the gas from inside the pot 25.

[0128] Next, rice cooking control unit 97 operates solenoid 67b to cause pressure regulating valve 67 to open steam discharge passage 66, connecting the inside of pot 25 to the outside of rice cooker 2. Outside air then flows into pot 25, which is in a reduced pressure state, from steam vent 65 through steam discharge passage 66, and the internal pressure of pot 25 returns to atmospheric pressure. After that, rice cooking control unit 97 further operates solenoid 67b to cause pressure regulating valve 67 to close steam discharge passage 66, allowing gas to flow through the path connecting pot 25 and reduced pressure pump 68, and operates reduced pressure pump 68 to remove the gas from inside pot 25.

[0129] In other words, when the soaking process starts, the internal pressure of pot 25 fluctuates. The fluctuations in the internal pressure of pot 25 expel the air inside the rice and allow water to penetrate to the center of the rice in place of the expelled air.

[0130] The display control unit 93 lights up the light-emitting diode directly below the character string "vacuum" each time the internal pressure of the pot 25 is reduced below atmospheric pressure, and turns off the light-emitting diode directly below the character string "vacuum" each time the internal pressure of the pot 25 is restored to atmospheric pressure.

[0131] The start of the soaking process also marks the start of the preheating process, which involves heating pot 25 with heating coil 31 before the rice volume determination process, thereby raising the initial temperature of pot 25 and, ultimately, the initial temperature of the food being cooked.

[0132] The rice cooking control unit 97, which executes the preheating process, energizes the heating coil 31 at a predetermined output and for a predetermined preheating time to raise the temperature of the food to be cooked. The energization type applied to the preheating process does not depend on the amount of rice to be cooked, as it is executed before the rice cooking amount determination process. The energization type applied to the preheating process may be a specific energization type, or it may vary depending on the pan temperature Ti. The energization type applied to the preheating process may be a specific energization type corrected depending on the pan temperature Ti, or it may be selected from multiple energization types with different outputs and energization times for the heating coil 31 depending on the pan temperature Ti.

[0133] In other words, the preheating step may vary the amount of heat input from heating coil 31 to pot 25 and the food to be cooked based on the initial temperature of the food to be cooked in the preheating step. In the preheating step, if the initial temperature Tps of pot 25 in the preheating step is lower than a predetermined temperature, for example, 23 degrees Celsius, pot 25 is heated by heating coil 31, and if the initial temperature Tps of pot 25 in the preheating step is equal to or higher than the predetermined temperature, no current is applied to heating coil 31 and pot 25 is not heated. In other words, if the initial temperature Tps of pot 25 in the preheating step is equal to or higher than the predetermined temperature, the preheating step is not substantially performed.

[0134] Furthermore, in the preheating step, the lower the initial temperature of the food to be cooked in the preheating step, the longer the heating of pot 25 may be continued by heating coil 31. In the preheating step, if the initial temperature Tps of pot 25 in the preheating step is lower than a first predetermined temperature, for example, 13 degrees Celsius, heating coil 31 heats pot 25 continuously for a first predetermined time, for example, 5 minutes, whereas if the initial temperature Tps of pot 25 in the preheating step is equal to or higher than the first predetermined temperature and lower than a second predetermined temperature, for example, 23 degrees Celsius, heating coil 31 heats pot 25 continuously for a second predetermined time shorter than the first predetermined time, for example, 3 minutes.

[0135] The temperature of the pot 25 is affected by the temperature of the rice, the temperature of the water, and the temperature of the atmosphere around the rice cooker 2, but it usually represents the temperature of the food being cooked.

[0136] The preheating process is carried out for, for example, about 5 minutes so as not to unnecessarily extend the time required for the entire rice cooking operation and so as to be able to properly heat the low-temperature food to be cooked.

[0137] When the preheating process is completed, the rice cooking control unit 97 moves to the rice cooking amount determination process. The rice cooking control unit 97 heats the pot 25 with the heating coil 31 to change the pot temperature Ti detected by the lid temperature sensor 85, and determines the amount of rice to be cooked based on the change in the pot temperature Ti.

[0138] Lid temperature sensor 85 detects the temperature of the outer surface of pot 25, and heating coil 31 electromagnetically heats heating element 25b located on the outer surface of pot 25. Therefore, it is expected that the difference between pot temperature Ti detected when heating coil 31 is energized and the temperature of the food being cooked will be larger than the difference between pot temperature Ti detected when heating coil 31 is de-energized and the temperature of the food being cooked.

[0139] Therefore, it is preferable that the rice cooking control unit 97 has a non-heating period in which the heating coil 31 is stopped and the pot 25 is not heated after the preheating process and before the rice cooking amount determination process is started. In other words, it is preferable that the soaking process has a non-heating period in which the heating coil 31 is stopped after the preheating process and before the initial temperature of the pot 25 is detected in the rice cooking amount determination process. By doing so, the pot temperature sensor 46 can reduce the discrepancy between the pot temperature Ti and the temperature of the food to be cooked, and more accurately detect the initial temperature of the food to be cooked in the rice cooking amount determination process. More accurate detection of the initial temperature of the food to be cooked in the rice cooking amount determination process improves the accuracy of determining the amount of cooked rice.

[0140] Furthermore, if there are multiple heating coils 31, the rice cooking control unit 97 can use at least one of the heating coils 31 to heat the pot 25. By doing so, the rice cooking control unit 97 can increase the temperature of the food to be cooked in the rice cooking amount determination process, for example, the initial temperature, thereby improving the accuracy of determining the amount of cooked rice.

[0141] The non-heating period may be, for example, about 30 seconds so as not to unnecessarily extend the time required for the entire rice cooking operation and so that the pot temperature sensor 46 can properly detect the initial temperature of the food being cooked in the rice amount determination process.

[0142] The rice cooking control unit 97, which executes the rice cooking amount determination process, energizes the heating coil 31 at a predetermined output and for a predetermined energization time, and then stops the heating coil 31. The rice cooking control unit 97 determines the amount of rice cooked based on the change in the pot temperature Ti during the rice cooking amount determination process.

[0143] Here, we define the initial temperature Ts of the pot 25 in the rice cooking amount determination process, the maximum temperature Tmax of the pot 25 in the rice cooking amount determination process, the final temperature Te of the pot 25 in the rice cooking amount determination process, a first variable V1 obtained by subtracting the initial temperature Ts from the final temperature Te, and a second variable V2 obtained by subtracting the final temperature Te from the maximum temperature Tmax.

[0144] The rice cooking control unit 97, which executes the rice cooking amount determination process, energizes the heating coil 31 to heat the food from its initial temperature Ts to its maximum temperature Tmax. The rice cooking control unit 97 may predetermine the output and energization time of the heating coil 31 and allow the food to reach its maximum temperature Tmax, or it may control the output and energization time of the heating coil 31 so that the food reaches the predetermined maximum temperature Tmax. When the food reaches the maximum temperature Tmax, the rice cooking control unit 97 cuts off the power to the heating coil 31 for a predetermined temperature-reducing time, stopping the heating coil 31. This causes the temperature of the food to drop. The rice cooking control unit 97 may predetermine the time to allow the final temperature Te of the food to be determined, or it may wait until the food reaches the predetermined final temperature Te before completing the rice cooking amount determination process. The rice cooking control unit 97 determines the amount of rice cooked based on changes in the pot temperature Ti, i.e., the initial temperature Ts, the maximum temperature Tmax, and the final temperature Te.

[0145] The specified power-on time is set so that a temperature drop occurs that allows the amount of cooked rice to be determined after the food to be cooked has been heated by the heating coil 31. The heating coil 31 that is powered in the rice cooking amount determination step may be the second coil 31d that is closer to the pan temperature sensor 46, the first coil 31u that is farther from the pan temperature sensor 46, or all of the heating coils 31. By powering only the first coil 31u that is farther from the pan temperature sensor 46 in the rice cooking amount determination step, the influence of the heating coil 31 on the detection result of the pan temperature sensor 46 is reduced, and the accuracy of determining the amount of cooked rice can be improved.

[0146] When the temperature rising time is over, the rice cooking control unit 97 shifts to the soaking process.

[0147] The rice cooking control unit 97 that executes the soaking process energizes the heating coil 31 to heat the pot 25. The energization type applied to the soaking process may be a specific energization type that does not depend on the amount of rice cooked determined in the rice cooking amount determination process, or may be selected from a plurality of cooking types that differ in output and energization time of the heating coil 31 according to the amount of rice cooked, or may be a specific energization type corrected according to the amount of rice cooked.

[0148] Furthermore, the rice cooking control unit 97 energizes or cuts off the heating coil 31 throughout the entire soaking process so that the temperature Ti inside the pot does not exceed 60° C. In this way, the rice cooker 2 prevents the rice from gelatinizing during the soaking process, avoiding poorly cooked rice.

[0149] When the soaking time is over, the rice cooking control unit 97 shifts to the boiling heating process.

[0150] During the boiling heating process, the rice cooking control unit 97 energizes the heating coil 31 until it detects that the food has boiled. The rice cooking control unit 97 heats the food in the pot 25 more strongly than during the soaking cooking process, raising the temperature of the food to boiling temperature in a short period of time. The rice cooking control unit 97 stops the pressure reducing pump 68 and opens the pressure adjusting valve 67. This immediately restores the internal pressure of the pot 25 to atmospheric pressure. The display control unit 93 turns off the light-emitting diode located directly below the word "vacuum."

[0151] The power supply pattern used to boil the food preferably sequentially consists of energizing the first coil 31u, de-energizing a period, energizing the second coil 31d, and de-energizing a period. The rice cooking control unit 97 also preferably changes the power supply time of the heating coil 31 according to the amount of rice to be cooked. For example, the power supply time of the second coil 31d is changed inversely proportional to the amount of rice to be cooked, the power supply time of the first coil 31u is set to be directly proportional to the amount of rice to be cooked, and the repetition interval of the power supply pattern, i.e., the power supply pattern cycle, is set to be directly proportional to the amount of rice to be cooked.

[0152] Thereafter, when the temperature of the bottom of pot 25 reaches or exceeds a predetermined temperature, for example, 90°C, and the temperature of inner lid 61 reaches or exceeds a predetermined temperature, for example, 90°C, the rice cooking control unit 97 opens the pressure regulating valve 67 and begins detecting the boiling of the food to be cooked under atmospheric pressure. The display control unit 93 lights up the light-emitting diode located directly below the word "Pressurize" based on the internal pressure of pot 25 detected by pressure sensor 87. The rice cooking control unit 97 monitors the rate of temperature rise per unit time of the bottom of pot 25 or the rate of temperature rise per unit time of the inner lid 61, and determines that the food to be cooked has boiled when these rates of temperature rise fall below a predetermined rate.

[0153] The type of current flow used in the process of determining whether the food has boiled is different from the type of current flow used to boil the food. Also, it is preferable that the rice cooking control unit 97 change the time of current flow to the heating coil 31 depending on the amount of rice to be cooked, even in the process of determining whether the food has boiled.

[0154] To determine whether the water contained in the food being cooked is boiling, the rice cooking control unit 97 calculates the rate of increase per unit time of the pan temperature Ti or the rate of increase per unit time of the lid temperature. If the rate of increase of the pan temperature Ti is equal to or less than a predetermined temperature increase rate, for example, 3 degrees Celsius or less in 120 seconds, the rice cooking control unit 97 determines that the first boiling determination condition based on the pan temperature Ti is met. If the rate of increase of the lid temperature is equal to or less than a predetermined temperature increase rate, for example, 1 degree Celsius or less in 60 seconds, the rice cooking control unit 97 determines that the second boiling determination condition based on the lid temperature is met. If either or both of the two boiling determination conditions are met, the rice cooking control unit 97 determines that the food being cooked has boiled.

[0155] The judgment value for the rate of temperature rise of the pan temperature Ti and the judgment value for the rate of temperature rise of the lid temperature may differ depending on the amount of rice cooked. The rice cooking control unit 97 may determine that the food to be cooked has boiled when either the first boiling judgment condition or the second boiling judgment condition is met.

[0156] Incidentally, some rice cooking courses do not require the rice volume determination process during the soaking cooking process. For example, in a quick-cooking course designed to complete rice cooking as quickly as possible, it is not appropriate to perform the rice volume determination process during the soaking cooking process. Therefore, when a rice cooking course is being performed in which the rice volume determination process during the soaking cooking process is not required, the rice cooker 2 according to this embodiment determines the rice volume during the boiling heating process. The determination of the rice volume during the boiling heating process is conveniently referred to as the third determination method. The third determination method classifies the rice volume into multiple levels based on the time required for the pot temperature Ti of the pot 25 detected by the lid temperature sensor 85 to reach a predetermined determination temperature, for example, 70°C, and then boil. In other words, the third determination method determines the rice volume based on a time threshold.

[0157] The rice cooking control unit 97 in this embodiment energizes the heating coil 31 with multiple different energization patterns during the boiling heating process, and energizes the heating coil 31 with even different energization patterns during the process of determining whether the rice has boiled. In other words, the rice cooker 2 finely adjusts the energization pattern to suit the boiling of the water contained in the food, reducing uneven cooking of the rice.

[0158] Furthermore, the rice cooking control unit 97 can select, correct, or change the current supply type depending on the amount of rice to be cooked. In this way, the rice cooker 2 can carefully apply the current supply type that is best suited to the amount of rice to be cooked, reducing unevenness in the cooking of rice.

[0159] When the boiling heating process is completed, the rice cooking control unit 97 transitions to the boiling continuation process.

[0160] During the boiling continuation process, the rice cooking control unit 97 switches the power supply to the heating coil 31 to maintain the temperature of the bottom of the pot 25 at a predetermined temperature or higher, for example, 98 degrees Celsius or higher, and continuously powers the lid heater 58 to maintain the temperature of the inner lid 61 at a predetermined temperature or higher, for example, 98 degrees Celsius or higher.

[0161] If the pot temperature Ti reaches or exceeds a predetermined temperature, or if the temperature rises at a predetermined rate, for example, 0.5 degrees Celsius or more in 10 seconds, the rice cooking control unit 97 determines that the water in the pot 25 is starting to run out. When the rice cooking control unit 97 determines that the water in the pot 25 is starting to run out, it extends the power supply time for the heating coil 31.

[0162] When the rate of temperature rise at the bottom of the pot 25 reaches a predetermined rate or exceeds a predetermined temperature, or when the temperature reaches a dry-up temperature at which excess water in the pot 25 disappears, such as 120 degrees Celsius, the rice cooking control unit 97 determines that the food is cooked and ends the boiling continuation process.

[0163] When the boiling continuation process is completed, the rice cooking control unit 97 transitions to the soaking process.

[0164] During the soaking process, the rice cooking control unit 97 switches the power supply to the lid heater 58 based on the lid temperature to prevent condensation from forming on the inner lid 61. The rice cooking control unit 97 also switches the power supply to the heating coil 31 based on the pot temperature Ti to manage the temperature of the food being cooked. The soaking process continues for a predetermined period of time.

[0165] When the soaking process is completed, the rice cooking control unit 97 completes the rice cooking operation, and the keep-warm control unit 98 starts the keep-warm process.

[0166] When the rice cooking operation is completed, the heating control circuit board 42 outputs a display control signal corresponding to the completion of the rice cooking operation. The input / output control circuit board 75 receives this display control signal and controls the display operation of the display unit 76 and the notification operation of the notification unit 88 to notify the user that the rice cooking operation is completed.

[0167] Keep-warm control unit 98 causes heating coil 31 to generate heat until the temperature of the rice drops from the freshly cooked temperature, essentially 100°C, to the keep-warm temperature, essentially 73°C, and continues to cause heating coil 31 to generate heat even after the keep-warm temperature has stabilized at 73°C. Keep-warm control unit 98 adjusts the output of heating coil 31 so that the temperature of the bottom of pot 25 remains constant.

[0168] The rice cooker 2 can also reheat the rice in the pot 25.

[0169] Next, the method for determining the amount of cooked rice by the rice cooker 2 will be described in more detail.

[0170] Fig. 8 is a diagram showing a first determination method as an example of a method for determining the amount of cooked rice in a rice cooker according to an embodiment of the present invention. Fig. 9 is a diagram showing a second determination method as another example of a method for determining the amount of cooked rice in a rice cooker according to an embodiment of the present invention.

[0171] As shown in Figures 8 and 9, the rice cooking control unit 97 of the rice cooker 2 of this embodiment heats the pot 25 with the heating coil 31, changing the temperature at the bottom of the pot detected by the pot temperature sensor 46, and determines the amount of cooked rice using multiple determination methods based on the change in the temperature at the bottom of the pot.

[0172] First, a first variable V1 is defined as the final temperature Te of the pot 25 minus the initial temperature Ts of the pot 25 in the rice cooking amount determination process (first variable V1 = final temperature Te - initial temperature Ts), and a second variable V2 is defined as the maximum temperature Tmax of the pot 25 minus the final temperature Te of the pot 25 (second variable V2 = maximum temperature Tmax - final temperature Te). Figures 8 and 9 are plotted with the first variable V1 on the horizontal axis and the second variable V2 on the vertical axis. Therefore, the first and second determination methods share the pot bottom temperature (pot temperature Ti) detected by the pot temperature sensor 46. In other words, the first and second determination methods are implemented based on the detection results of the pot temperature sensor 46, without the need to add a detector for detecting physical quantities to the rice cooker 2. In other words, when the first and second determination methods are implemented as software executed by the rice cooking control unit 97, modifications to the hardware of the rice cooker 2 are kept to a minimum.

[0173] 8 and 9 also show data D4 detected when cooking an item containing 4 cups of rice, data D3 detected when cooking an item containing 3 cups of rice, data D2 detected when cooking an item containing 2 cups of rice, data D1.5 detected when cooking an item containing 1.5 cups of rice, data D1 detected when cooking an item containing 1 cup of rice, and data D0.5 detected when cooking an item containing 0.5 cups of rice. For ease of explanation, "data detected when cooking an item" will be referred to simply as "determination data" below.

[0174] As shown in Figure 8, the first determination method determines the amount of cooked rice based on at least one first threshold A that is perpendicular to the horizontal axis and parallel to the vertical axis and takes a constant for the first variable V1, and at least one second threshold B that is parallel to the horizontal axis and perpendicular to the vertical axis and takes a constant for the second variable V2. In other words, the thresholds of the first determination method are depicted as a straight line with no slope when illustrated with the first variable V1 on the horizontal axis and the second variable V2 on the vertical axis.

[0175] For example, thresholds a1, a2, and a3 are set as first thresholds A, and threshold b1 is set as second threshold B. Threshold a1 is the smallest and threshold a3 is the largest. In other words, there is a relationship of (threshold a1)<(threshold a2)<(threshold a3).

[0176] The amount of cooked rice is determined into four classes based on thresholds A and B. For convenience, the four classes are called "extra large," "large," "medium," and "small" in order of the amount of cooked rice. An extra large class is determined to be 4 go or more according to the shakkan system, a large class is determined to be 3 go, a medium class is determined to be 2 go or 1.5 go, and a small class is determined to be 1 go or 0.5 go of rice.

[0177] A value below threshold a1 is determined to be extra large regardless of threshold B. A value above threshold a1 and below threshold a2 and above threshold b1 is determined to be extra large. A value above threshold a1 and below threshold a2 and below threshold b1 is determined to be large. A value above threshold a2 and below threshold a3 and above threshold b1 is determined to be large. A value above threshold a2 and below threshold a3 and below threshold b1 is determined to be medium. A value above threshold a3 and above threshold b1 is determined to be medium. A value above threshold a3 and below threshold b1 is determined to be small.

[0178] As shown in Figure 9, the second determination method determines the amount of cooked rice based on a threshold value α ((threshold value α) = (coefficient) × (first variable V1) + (second variable V2)), which is expressed by at least one linear function with a positive slope. The threshold value α has a positive slope that is not zero. In other words, the threshold value of the second determination method is described as a straight line sloping upward to the right when illustrated with the first variable V1 on the horizontal axis and the second variable V2 on the vertical axis. When there are multiple threshold values ​​α, the respective threshold values ​​α do not intersect with each other within the temperature conditions to which the cooked food is exposed in the cooked rice amount determination process, that is, the temperature range higher than the melting point and lower than the boiling point of the cooked food.

[0179] For example, thresholds α1, α2, α3, α4, and α5 are set from the side closest to the horizontal axis. The intercepts on the vertical axis are set such that threshold α1 is the smallest and threshold α5 is the largest. In other words, there is a relationship of (intercept of threshold α1)<(intercept of threshold α2)<(intercept of threshold α3)<(intercept of threshold α5)<(intercept of threshold α5). The intercepts correspond to the value of the second variable V2 when the first variable V1 is zero.

[0180] In the second determination method according to this embodiment, the linear function does not include a relationship in which the slope is zero.

[0181] The amount of cooked rice is determined into six classes based on these thresholds α1 to α5. The six classes are called "extra large determination," "large determination," "medium determination," "small / medium determination," "small determination," and "very small determination," in order of the largest amount of cooked rice. An extra large determination is for cooked rice containing 4 go or more according to the shakkanho system, a large determination is 3 go, a medium determination is 2 go, a small determination is 1.5 go, a small determination is 1 go, and a very small determination is for cooked rice containing 0.5 go. In other words, the definitions of the classes "extra large determination," "large determination," "medium determination," and "small determination" in the first determination method are the same as the definitions of the classes in the first determination method.

[0182] A value equal to or greater than the threshold α5 is determined to be extra large. A value equal to or greater than the threshold α4 but less than the threshold α5 is determined to be large. A value equal to or greater than the threshold α3 but less than the threshold α4 is determined to be medium. A value equal to or greater than the threshold α2 but less than the threshold α3 is determined to be small or medium. A value equal to or greater than the threshold α1 but less than the threshold α2 is determined to be small. A value less than the threshold α1 is determined to be extremely small.

[0183] The inventors discovered that the respective determination data shown in Figures 8 and 9 are affected by factors such as the level of the power supply voltage supplied to the rice cooker 2, the ambient temperature around the rice cooker 2, and the temperature of the food to be cooked in the rice cooker 2. The temperature of the water contained in the food is dominant in determining the temperature of the food. Even for the same amount of food, the lower the power supply voltage, ambient temperature, and food temperature, the more the determination data obtained in the rice cooking amount determination process tends to shift downward and to the left. The higher the power supply voltage, ambient temperature, and food temperature, the more the determination data obtained in the rice cooking amount determination process tends to shift upward and to the right. Note that the subscript "d" is added to the data shown in Figures 8 and 9 to indicate a downward and to the left shift, and the subscript "u" is added to indicate a upward and to the right shift.

[0184] For ease of explanation, factors such as the level of the power supply voltage supplied to the rice cooker 2, the level of the ambient temperature around the rice cooker 2, and the level of the temperature of the food to be cooked placed in the rice cooker 2 are referred to as factors affecting the judgment accuracy.

[0185] Here, we focus on the judgment data for the cooked rice containing 2 cups of rice shown in Figure 8. It is preferable that this judgment data be judged as "medium." However, with the first judgment method shown in Figure 8, it was found that when at least one of the factors affecting the judgment accuracy is low, the judgment data may deviate into the "high judgment" range. In other words, the first judgment method may erroneously judge the amount of cooked rice as one level higher than the level that should actually be judged. However, the factors affecting the judgment accuracy may combine randomly, causing a large overlapping shift in the judgment data, or they may cancel each other out and suppress a shift in the judgment data.

[0186] The rice cooking amount determined in the rice cooking amount determination process is used in subsequent processes, and an erroneous determination of the rice cooking amount by one level higher does not significantly affect the taste of the rice. However, in recent years, the rice cooking amount has been utilized in applications other than rice cooking, such as rice consumption management and a monitoring function for monitoring the living conditions of the user of the rice cooker 2, i.e., the monitoring target, based on rice consumption amount. In such applications, a more accurate determination of the rice cooking amount may be required than in rice cooking. In other words, in rice consumption management, a difference in the determination result of one cup, which corresponds to a difference in the level of erroneous determination, may significantly distort the cumulative consumption value. For example, if the rice cooking amount is repeatedly determined to be one cup higher than the actual value, the cumulative rice consumption value may be higher than the actual value, which may lead to a false impression that there is insufficient rice remaining, even when there is still rice in stock. Furthermore, when it comes to monitoring functions, considering the general consumption of the age group of the person being monitored, changes or fluctuations in the judgment results for one cup may cause unnecessary concern for the person being monitored.

[0187] Therefore, the second determination method in FIG. 9 has thresholds (threshold α1, threshold α2, threshold α3, threshold α4, and threshold α5) described by a linear function along the shift direction of data due to the determination accuracy influence factors.

[0188] For ease of explanation, the cooked rice amount determined by the first determination method will be referred to as the first determination amount, and the determined amount determined by the second determination method will be referred to as the second determination amount. In other words, the second determination method determines the second determination amount, which has better determination accuracy than the first determination amount.

[0189] Of the factors that affect the judgment accuracy, the factor that can be easily controlled by the rice cooker 2 is the temperature of the food to be cooked placed in the rice cooker 2. The rice cooker 2 can easily raise the temperature of the food to be cooked by heating the pot 25 with the heating coil 31.

[0190] Furthermore, the detection performance of the thermistor that serves as lid temperature sensor 85 at low temperatures is lower than that at high temperatures. The decline in the detection performance of lid temperature sensor 85 at low temperatures can also lead to an erroneous determination of the amount of cooked rice. By heating pot 25 with heating coil 31 to raise the temperature of the food being cooked, rice cooker 2 can obtain data for determination in the temperature range where lid temperature sensor 85 has high detection performance.

[0191] Therefore, the rice cooker 2 according to this embodiment executes a preheating process in which the heating coil 31 heats the pot 25 before the cooked rice amount determination process to raise the initial temperature of the pot 25 in the cooked rice amount determination process, i.e., the initial value of the temperature at the bottom of the pot. The preheating process improves the accuracy of any method of determining the cooked rice amount, including the first determination method, which is executed based on the change in the temperature at the bottom of the pot during the soaking process, and the second determination method. For example, when determining the cooked rice amount for food containing 2 cups of rice using the first determination method, the tendency for the determination data to shift downward and to the left due to a low temperature of the food is suppressed, improving the accuracy of determining the cooked rice amount using the first determination method.

[0192] The minimum time for the preheating process is preferably set depending on the accuracy of the rice cooking amount determination. The minimum time for the preheating process is preferably equal to or longer than the minimum amount of rice cooking that can be determined, for example, the shortest time required to determine between a minimum amount of rice cooking and a larger amount of rice cooking.

[0193] Furthermore, it is preferable that the amount of heat input in the preheating process be set according to the accuracy of the rice cooking amount determination. Raising the temperature of an object with a low initial temperature and shifting the determination data to the upper right improves the accuracy of determining the amount of cooked rice, while raising the temperature of an object with a high initial temperature and shifting the determination data to the upper right may worsen the accuracy of determining the amount of cooked rice. Therefore, it is preferable that the amount of heat input to the object in the preheating process be changed based on the initial temperature of the object in the preheating process. By doing so, the initial temperature of the object in the rice cooking amount determination process can be controlled to a temperature range that is more appropriate in terms of the accuracy of the determination.

[0194] The rice cooker 2 determines the amount of food to be cooked based on changes in the pan temperature Ti using multiple methods, namely, a first determination method and a second determination method. The first determination method and the second determination method classify the amount of rice to be cooked into multiple levels.

[0195] Here, let's assume that suitable rice cooking courses have already been set for each of the four classes ("extra large," "large," "medium," and "small") based on the first determination method. These preset rice cooking courses differ in one or more of the following settings: rice type, cooking method, cooked rice hardness, and cooking time. Rice types include, for example, over 60 different brands of rice, as well as rice with different degrees of polishing, such as brown rice, polished rice, and polished rice. The number of rice cooking courses is calculated by multiplying the number of selectable settings, such as the number of cooking method settings, the number of selectable hardness settings, and the number of selectable cooking time settings, by the number of rice types. The total number of rice cooking courses may exceed 2,000. In other words, rice cooker 2 may be capable of implementing a large number of rice cooking courses exceeding 2,000, and the rice cooker 2 cooks rice by selectively selecting, adjusting, and correcting a cooking course from the numerous rice cooking courses according to the amount of rice to be cooked. The settings for these numerous rice cooking courses and the changes to the cooking courses depending on the amount of rice cooked are information that already has intangible asset value, and acquiring them would require a huge amount of work time. If we continue to make effective use of the existing rice cooking courses that have such value, it would be unrealistic to immediately abandon the first determination method and completely switch to the second determination method.

[0196] Therefore, the rice cooker 2 mainly uses the first determination method to control the rice cooking operation based on the rice cooking amount, and the second determination method for purposes other than rice cooking. However, the first determination method and the second determination method may be combined and used to control the rice cooking operation. For example, for the "extra large determination," "large determination," "medium determination," and "small determination" results that overlap between the first determination method and the second determination method, the determination method applied to the rice cooking amount determination process may be switched to the second determination method sequentially, starting with the rice cooking courses for which operation verification based on the rice cooking amount determined by the second determination method has been completed. Furthermore, the determination method applied to the rice cooking amount determination process may be switched to the second determination method sequentially, starting with the rice cooking courses for which the settings corresponding to the "small / medium determination" and "extra small determination," which are not included in the first determination method but are only included in the second determination method, have been confirmed.

[0197] In recent years, lifestyles have changed, leading to a trend toward individual meals. As a result, the average amount of rice cooked at one time by rice cooker 2 has tended to decrease compared to the past. Therefore, the number of classes for the second judgment amount is greater than the number of classes for the first judgment amount. The increments of the classes for the second judgment amount are smaller on the side of smaller rice amounts than on the side of larger rice amounts. In other words, by making "small / medium judgment" and "extremely small judgment" judgments as in the second judgment method, it is possible to finely control rice cooking operations more optimally from various perspectives, such as power consumption and taste, even for cooking rice for relatively small amounts of rice, such as 1.5 cups and 0.5 cups. Furthermore, by accurately determining the amount of rice cooked for relatively small amounts, such as 1.5 cups to 0.5 cups, rice cooker 2 can manage rice consumption and its monitoring function, which is based on rice consumption, to better adapt to modern lifestyles.

[0198] The first and second determination methods are performed in the soaking cooking process, while the third determination method, which is performed in a process after the soaking cooking process, for example, in the boiling heating process, determines the amount of cooked rice based on a threshold value related to time. In other words, the third determination method determines the amount of cooked rice based on a threshold value that cannot be shown in Figures 8 and 9.

[0199] In addition to the rice cooking course, the courses include a cooking course and a maintenance course, but the rice cooking control unit 97 does not determine the amount of rice to be cooked in the cooking course or maintenance course. In other words, the first, second, and third determination methods are not executed in the cooking course and maintenance course.

[0200] Furthermore, the rice cooking control unit 97 does not transmit the amount of rice cooked to the outside of the machine during the cooking course and maintenance course. In other words, during the cooking course and maintenance course, the first, second, and third determination methods are not executed, and the amount of rice cooked is not transmitted to the information terminal 3 and the server 7.

[0201] Fig. 10 is a diagram showing a second example of the first determination method for a rice cooker according to an embodiment of the present invention. Fig. 11 is a diagram showing a second example of the second determination method for a rice cooker according to an embodiment of the present invention.

[0202] The first determination method shown in Fig. 11 and the second determination method shown in Fig. 12 are applied to a rice cooking course for cooking porridge, i.e., a porridge cooking course, whereas the first determination method shown in Fig. 8 and the second determination method shown in Fig. 9 are applied to a course for cooking regular cooked rice.

[0203] 10 and 11 commonly illustrate data D1 detected when porridge is made with food containing 1 go of rice, data D0.5 detected when porridge is made with food containing 0.5 go of rice, and data D0.25 detected when porridge is made with food containing 0.25 go of rice. The threshold values ​​for the first determination method in Fig. 10 are shown in accordance with Fig. 8. The threshold values ​​for the second determination method in Fig. 11 are shown in accordance with Fig. 9. However, an oversized rice is determined to be 1 go or more according to the shakkanho system, a large rice is determined to be 0.5 go, and a small rice is determined to be 0.25 go of rice.

[0204] The ratio of rice to water in porridge is significantly different from that in regular cooked rice, with the proportion of water being extremely high, meaning that the heat capacity of the cooked rice is significantly different. Therefore, it can be seen that the factors affecting the accuracy of the determination have a stronger influence in the first determination method. On the other hand, the second determination method is not affected by the factors affecting the accuracy of the determination and can determine the amount of cooked rice with high accuracy.

[0205] In other words, the first and second determination methods classify the amount of rice to be cooked into multiple levels based on at least one threshold value set for each rice cooking course. This allows the rice cooker 2 to determine the amount of rice to be cooked by applying a determination method suitable for each of the multiple rice cooking courses.

[0206] The change in pan bottom temperature (change in pan temperature Ti) detected by pan temperature sensor 46 used in the first and second determination methods is not limited to a combination of at least one temperature increase and at least one temperature decrease, as shown in FIG. 7 , in which heating coil 31 is energized to increase pan temperature Ti from initial temperature Ts to maximum temperature Tmax, and then heating coil 31 is stopped to decrease pan temperature Ti from maximum temperature Tmax to final temperature Te. The change in pan temperature Ti need only include at least one increase in pan temperature Ti. For example, the change in pan temperature Ti may be a combination of a first increase in pan temperature Ti due to a high heat input and a rise or fall in pan temperature Ti due to a low heat input. The change in pan temperature Ti may also be a change due to only the first increase in pan temperature Ti. Furthermore, the change in pan temperature Ti may be a combination of at least one increase in pan temperature Ti followed by multiple increases in pan temperature Ti or multiple decreases in pan temperature Ti. In other words, rice cooker 2 may be able to implement a plurality of methods for determining the amount of cooked rice based on the change in the temperature at the bottom of the pot detected by pot temperature sensor 46.

[0207] FIG. 12 is a front view of an example of an information terminal according to an embodiment of the present invention.

[0208] 12, an information terminal 3 according to an embodiment of the present invention is, for example, a smartphone. The information terminal 3 includes, for example, a display unit 101 as an output device, an input device 102 that accepts user input, a communication module 103 that can send and receive various information, and a terminal control unit 105.

[0209] The display unit 101 is a display capable of displaying various types of information.

[0210] The input device 102 is, for example, a touch panel 102a that is provided over the display unit 101. The input device 102 may be a voice input unit 102b that accepts voice input.

[0211] The communication module 103 is capable of communicating with the rice cooker 2 via short-range wireless communication 5. The communication module 103 is connected to the network NW either directly or via a repeater 15. The communication module 103 may be capable of communicating with the rice cooker 2 and the server 7 via the network NW.

[0212] FIG. 13 is a block diagram of a smartphone as an example of an information terminal according to an embodiment of the present invention.

[0213] As shown in FIG. 13, the terminal control unit 105 of the information terminal 3 includes a CPU, a memory serving as a storage unit 107, a timer serving as a timekeeping unit, and an input / output interface.

[0214] An input port of the terminal control unit 105 is connected to the input device 102 and the communication module 103. An output port of the terminal control unit 105 is connected to the display unit 101 as an output device and the communication module 103.

[0215] The terminal control unit 105 receives, at an input port, an operation signal output by the input device 102. The terminal control unit 105 also receives, at an input port, information received by the communication module 103.

[0216] The terminal control unit 105 outputs a display control signal from the output port to the display unit 101. The terminal control unit 105 outputs information to be transmitted outside the information terminal 3 to the communication module 103 from the output port.

[0217] These functions of the terminal control unit 105 are realized by the CPU executing programs recorded in memory. The programs cause the terminal control unit 105 to realize, for example, a communication control function 108 and a display control function 109. The programs for realizing these functions in the information terminal 3 are hereinafter referred to as "management applications."

[0218] The communication control function 108 controls the communication operation of the communication module 103. The communication control function 108 operates the communication module 103 to transmit various information from the information terminal 3 to the rice cooker 2 directly without going through the server 7, or indirectly via the server 7, and to receive various information transmitted by the rice cooker 2.

[0219] It is preferable that the rice cooker 2, information terminal 3, and server 7 share the current state and settings of the rice cooker 2 without delay. Therefore, it is preferable that the rice cooker 2, information terminal 3, and server 7 exchange information indicating the current state and settings of the rice cooker 2 at predetermined intervals, for example, every five minutes. Therefore, the information terminal 3 and server 7 individually obtain information from the rice cooker 2 at predetermined intervals and send the information to the rice cooker 2. It is sufficient for at least the rice cooker 2 and information terminal 3 to share the current state and settings of the rice cooker 2 without delay. From the perspective of load balancing, the server 7 and storage device 8 do not need to continuously store or retain the current state and settings of the rice cooker 2. It is preferable that the communication module 111 of the rice cooker 2 transmit all or part of the information stored in the storage device of the heating control circuit board 42 to the information terminal 3 and server 7 at predetermined intervals. It is preferable that the communication module 103 of the information terminal 3 receive the information transmitted by the rice cooker 2 at predetermined intervals.

[0220] The display control function 109 controls the display operation of the display unit 101. The display control function 109 causes the display unit 101 to display various screens.

[0221] The display control function 109 displays a plurality of elements, such as backgrounds and character strings, on the display unit 101, based on, for example, various information received by the communication module 103. The display control function 109 displays, for example, information received by the communication control function 108 on the display unit 101. For ease of explanation, "a plurality of elements, such as backgrounds, images, symbols, character strings, etc., that the display control function 109 displays on the display unit 101, based on, for example, various information received by the communication module 103" will be referred to as "display elements" hereinafter.

[0222] However, rice as a consumer product is primarily a staple food, and it is difficult for users of Rice Cooker 2 to tolerate being out of stock (running out of stock). Therefore, users of Rice Cooker 2 may replenish their inventory in a timely manner without the help of a system that supports rice ordering. Furthermore, users of Rice Cooker 2 may purchase new rice at the time of shipment, regardless of the amount of stock.

[0223] On the other hand, due to recent changes in food culture, it is now expected that rice will be consumed in dishes other than rice, such as risotto, without using a rice cooker 2.

[0224] Therefore, the rice cooking system 1 according to this embodiment has a remaining rice amount display function that displays the remaining amount of rice, i.e., the inventory amount, to the user. Note that the terms "remaining amount of rice" and "inventory amount of rice" are used interchangeably.

[0225] The remaining rice amount display function executed by the rice cooking system 1 will be described below in accordance with a specific input / output interface.

[0226] FIG. 14 is a diagram showing a first example of a first screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0227] FIG. 15 is a diagram showing a second example of the first screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0228] The first screen WS1 shown in FIGS. 14 and 15 is an example of a so-called top screen of the information terminal 3.

[0229] 14 and 15, when the management application is started, the display unit 101 of the information terminal 3 according to this embodiment displays a first screen WS1 as an initial screen. The display content of the display unit 101 is controlled by a display control function 109.

[0230] That is, the rice cooking system 1 comprises a communication module 103 as a receiving unit capable of receiving the current status of the rice cooker 2, a memory unit 107 that stores the remaining amount of rice as a consumable item, and a display unit 101 that can display a first screen WS1 that simultaneously displays the current status of the rice cooker 2 and the remaining amount of rice. The remaining rice amount display function executed by the rice cooking system 1 receives the current status of the rice cooker 2, records the remaining amount of rice as a consumable item, and simultaneously displays the current status of the rice cooker 2 and the remaining amount of rice. The rice cooking system 1 that executes the remaining rice amount display function embodies a method for displaying the remaining amount of rice.

[0231] The first screen WS1 includes a plurality of first display elements 201.

[0232] The multiple first display elements 201 include, from the top of the first screen WS1, a model identification string 201a, a setting screen call icon 201b, a support screen call icon 201c, a model icon 201d, a status display string 201e, a brand send button 201f, a remaining rice amount adjustment button 201g, a rice cooking history call button 201h, a course introduction call button 201i, and a background 201j.

[0233] The model identification string 201a displays the model identification of the rice cooker 2 selected as the target for management by the management app as a string, for example, "rice cooker." The model identification may be, for example, the model name, the model number, or a string arbitrarily set by the user.

[0234] The setting screen call icon 201b displays, for example, a combination of an image of a "gear" and the character string "settings." When the setting screen call icon 201b is touched, the screen displayed on the display unit 101 transitions to the setting screen.

[0235] The support screen call icon 201c displays, for example, a combination of an image of a "speech bubble" and the character string "support." When the support screen call icon 201c is touched, the screen displayed on the display unit 101 transitions to the support screen.

[0236] The model icon 201d displays a large image that evokes the rice cooker 2 selected as the object to be managed by the management application.

[0237] The status display string 201e displays the current status of the rice cooker 2 selected as the target for management by the management app as a string, for example, "Stopped." The current status of the rice cooker 2 includes "Running," which indicates that rice is being cooked, "Stopped," which indicates that rice is not being cooked, and "Offline," which indicates that communication between the rice cooker 2 and the information terminal 3 cannot be established. If a status other than "Offline" is displayed, the rice cooker 2 is online.

[0238] The brand send button 201f includes a first title character string 201k that displays "Brand Send" as a character string, and a brand send screen call icon 201m that displays, for example, ">" as an image. The first title character string 201k is displayed left-justified on the brand send button 201f, and the brand send screen call icon 201m is displayed right-justified on the brand send button 201f.

[0239] The rice remaining amount adjustment button 201g functions as an adjustment input unit that accepts adjustment operations related to the remaining amount of rice. The rice remaining amount adjustment button 201g includes a second title string 201n that displays "rice stock amount" as a string of characters, a stock amount string 201o, and a rice remaining amount adjustment input unit call icon 201p that displays, for example, an image of ">". The second title string 201n is displayed left-justified on the rice remaining amount adjustment button 201g, the rice remaining amount adjustment input unit call icon 201p is displayed right-justified on the rice remaining amount adjustment button 201g, and the stock amount string 201o is displayed immediately to the left of the rice remaining amount adjustment input unit call icon 201p.

[0240] 14 displays the rice inventory amount by combining the word "approximately," a numerical value such as "10.00," and a unit such as "kg" representing kilograms. The inventory amount string 201o corresponds to the display when the rice inventory amount grasped by the rice cooking system 1 and stored in the memory unit 107 is approximately 10.00 kilograms.

[0241] The inventory quantity string 201o in FIG. 15 can display the rice inventory quantity in the SI unit of kilograms or in the unit "go" based on the shakkanho system. The unit applied to the rice inventory quantity can be switched and selected on the setting screen that is displayed by touching the setting screen call icon 201b. When the unit applied to the rice inventory quantity is switched to "go" on the setting screen, the inventory quantity string 201o displays the rice inventory quantity by combining the string "approximately," a numerical value such as "66.6," and a unit such as "go." The rice cooking system 1 converts the unit using 1 go of rice = approximately 150 grams (g).

[0242] In Japan, rice is generally traded in kilograms or grams at stores where consumers can easily obtain rice, while rice is consumed in "go" units when cooking rice in rice cookers 2. The inventory quantity string 201o, which can be displayed by switching units as shown in Figures 14 and 15, can easily present the user with an inventory quantity that flexibly corresponds to both the distribution and consumption patterns of rice in Japan.

[0243] The rice cooking history call button 201h displays, for example, an image resembling a heart mark combined with the text "Favorite rice cooking history." When the rice cooking history call button 201h is touched, the screen displayed on the display unit 101 changes to a screen presenting favorite rice cooking courses and the history of rice cooking courses used to date.

[0244] The course introduction call button 201i displays, for example, a small image resembling a rice cooker 2 in combination with the text "Course introduction." When the course introduction call button 201i is touched, the screen displayed on the display unit 101 transitions to a screen introducing rice cooking courses.

[0245] Meanwhile, rice cooker 2 determines the amount of rice to be cooked while it is in the process of cooking rice, that is, when its current state is "operating." Rice cooking system 1 transmits the amount of rice to be cooked determined by rice cooker 2 from rice cooker 2, which is received by information terminal 3 as the amount of rice consumed, and can determine the latest rice inventory by subtracting the amount of rice consumed from the rice inventory stored in memory unit 107 of information terminal 3, and present this latest inventory to the user. In other words, as long as the user of rice cooking system 1 consumes rice using rice cooker 2, they can easily know the latest rice inventory determined by rice cooking system 1 without having to perform any operations related to increasing or decreasing the rice inventory.

[0246] However, during the period from when rice is taken out of the storage location, for example, the rice bin, until the information terminal 3 recognizes the amount of rice cooked by the rice cooker 2 as the amount of consumption, the latest amount of consumption is not reflected in the rice inventory. If the amount of rice inventory decreases to the amount of rice consumed in a few times, or the amount of rice cooked in a few cooking operations, this indefinite period of inventory may lead to rice being out of stock.

[0247] Therefore, the first screen WS1 simultaneously displays the status display string 201e and the stock quantity string 201o. In other words, the rice cooking system 1 according to this embodiment simultaneously displays the current status of the rice cooker 2 and the remaining amount of rice on the first screen WS1. This allows the user of the rice cooking system 1 to easily check the current status of the rice cooker 2 and the remaining amount of rice at the same time, regardless of the physical distance between the rice cooker 2 and the user. A user who can simultaneously check the current status of the rice cooker 2 and the remaining amount of rice can easily estimate the actual amount of rice in stock, making it easy to avoid running out of rice.

[0248] However, with recent changes in food culture, it is now expected that rice will be consumed in dishes other than cooked rice, such as risotto, without using a rice cooker 2. Therefore, the rice cooking system 1 according to this embodiment provides the user with an environment in which they can adjust the remaining amount of rice. The remaining amount adjustment operation for adding or reducing the amount of rice in stock will be explained in conjunction with a specific input / output interface. Let us assume that the remaining rice amount adjustment button 201g on the first screen WS1 is touched.

[0249] FIG. 16 is a diagram showing an example of a first sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0250] 16 is an example of a screen of a management application executed on the information terminal 3, and is an example of an inventory adjustment screen displayed by touching the rice remaining amount adjustment button 201g on the first screen WS1. The first sub-screen SS1 is displayed as a pop-up so as to overlap the first screen WS1.

[0251] As shown in Figure 16, the rice cooking system 1 of this embodiment displays on the display unit 101 an addition input unit 211 that accepts a remaining amount addition operation to add to the remaining amount of rice, and a reduction input unit 212 that accepts a remaining amount reduction operation to reduce the remaining amount of rice, in response to a remaining amount adjustment operation accepted by the rice remaining amount adjustment button 201g.

[0252] When the rice remaining amount adjustment button 201g on the first screen WS1 is touched, the first sub-screen SS1 pops up and is displayed overlapping the first screen WS1. While the first sub-screen SS1 is displayed, each first display element 201 on the first screen WS1 is displayed in gray, for example, in light gray, and does not accept touch operations.

[0253] The first sub-screen SS1 includes a plurality of first sub-display elements 215.

[0254] The plurality of first sub-display elements 215 are, for example, from the top of the first sub-screen SS1, a first title 215a, a close button 215b displayed with a crossed-out character, a stock quantity character string 215c, a stock quantity annotation area 215e, a second title character string 215f displaying the character string "Adjust stock", a rice remaining amount reduction button 215g displaying an image resembling a "-" and the character string "Reduce rice", and an image resembling a "+" and the character string "Add rice". a reduction commentary string 215i that is arranged just below the rice remaining amount reduction button 215g and displays the text "When rice is used in a device other than a rice cooker" to explain how to use the rice remaining amount reduction button 215g; an additional commentary string 215j that is arranged just below the rice remaining amount addition button 215h and displays the text "When rice is purchased or replenished" to explain how to use the rice remaining amount addition button 215h; and a notification string 215k.

[0255] The first heading 215a displays, for example, a small image resembling a measuring cup in combination with the text "Rice stock amount (approximate)."

[0256] The inventory quantity string 215c displays the amount of rice in stock by combining the word "approximately," a numerical value, for example, "10.00," and a unit, for example, "kg" meaning kilograms. The inventory quantity string 215c also displays the word "approximately," a numerical value, for example, "66.6," and a unit, for example, "go," in a parenthesized area. The inventory quantity string 215c allows the user to easily recognize the current amount of rice in stock as tracked by the rice cooking system 1.

[0257] The inventory amount annotation area 215e displays, for example, a combination of an image resembling a rice cooker 2, an image resembling a rice bin, a speech bubble containing the text "Notify when low," and the text "Estimates the amount of rice used during cooking and automatically updates the inventory amount (this may differ from the actual inventory amount)." The inventory amount annotation area 215e makes it easy for the user to recognize that when rice is cooked in the rice cooker 2, the rice cooking system 1 automatically updates the rice inventory amount, in this case, reducing it.

[0258] When the Reduce Rice Remaining Amount button 215g is touched, the display unit 101 pops up a Reduce Rice Remaining Amount screen so that it overlaps the first sub-screen SS1. As displayed in the reduction annotation string 215i, the Reduce Rice Remaining Amount button 215g is a reduction input unit 212 that is operated by the user to intentionally reduce the rice inventory amount when rice is used outside the rice cooker 2, that is, when the rice consumption estimation by the rice cooker 2 is bypassed and the rice cooking system 1 is unable to grasp the consumption estimation by the rice cooker 2 and the rice inventory amount decreases.

[0259] When the rice remaining amount addition button 215h is touched, the display unit 101 pops up a rice remaining amount addition screen so that it overlaps with the first sub-screen SS1. As shown in the additional comment string 215j, the rice remaining amount addition button 215h is an additional input unit 211 that is operated by the user to intentionally add to the rice inventory.

[0260] The notification string 215k displays the word "Notification" left-justified, and the string "Notify when rice reaches 2 kg (approximately 13 cups) or less," which represents the stock notification setting value for notifying that rice stock is low, right-justified. The notification string 215k lets the user know that the rice cooking system 1 will provide some kind of notification if the rice stock falls below the stock notification setting value. It is preferable that the stock notification setting value can be set by the user. By touching the notification string 215k or the bubble in the stock amount annotation area 215e, a settings screen will be displayed where the stock notification setting value can be set as desired.

[0261] The rice cooking system 1 according to this embodiment displays the remaining rice amount addition button 215h as the additional input unit 211 that accepts a remaining amount addition operation for adding to the remaining rice amount, and the remaining rice amount reduction button 215g as the reduction input unit 212 that accepts a remaining amount reduction operation for reducing the remaining rice amount, separately, separately, and independently on the display unit 101. Therefore, the rice cooking system 1 can easily reduce the rice inventory stored in the memory unit 107 by the remaining amount reduction operation not only when rice is consumed using the rice cooker 2, but also when rice is consumed for purposes other than cooking rice without using the rice cooker 2. Furthermore, the rice cooking system 1 can easily increase the rice inventory by the remaining amount addition operation, regardless of the reason. In other words, the user of the rice cooking system 1 can simply operate the remaining rice amount addition button 215h to add to the rice inventory, or can simply operate the remaining rice amount reduction button 215g to reduce the rice inventory for purposes other than using the rice cooker 2. By providing such a clear user interface, the rice cooking system 1 prevents the user from accidentally increasing or decreasing the amount of rice in stock, and provides an environment in which the user can easily increase or decrease the amount of rice in stock.

[0262] In addition, the rice cooking system 1 and information terminal 3 according to this embodiment may display the first sub-screen SS1 having the reduction input section 212 and the additional input section 211 superimposed on the first screen WS1. Alternatively, the rice cooking system 1 and information terminal 3 may display the reduction input section 212 and the additional input section 211 in addition to the multiple first display elements 201 of the first screen WS1. Alternatively, the rice cooking system 1 and information terminal 3 may display a screen (second screen) having the reduction input section 212 and the additional input section 211 next to the first screen WS1. Alternatively, the rice cooking system 1 and information terminal 3 may display two completely separate screens, transitioning from the first screen WS1 to the screen (second screen) having the reduction input section 212 and the additional input section 211. The display elements of the second screen may be the same as those of the first sub-screen SS1, or the number of display elements may be increased or decreased. In other words, the rice cooking system 1 and information terminal 3 may display the inventory adjustment screen as a pop-up superimposed on the top screen, or may display the inventory adjustment screen next to the top screen, or may display the inventory adjustment screen in place of the top screen. In addition, the rice cooking system 1 and the information terminal 3 may add and display the reduction input section 212 and the additional input section 211 to the top screen in response to the remaining amount addition operation, that is, may display the top screen so as to add the function of an inventory adjustment screen.

[0263] Next, it is assumed that the rice remaining amount reduction button 215g on the first sub-screen SS1 is touched with the aim of reducing the amount of rice stock kept by the rice cooking system 1.

[0264] FIG. 17 is a diagram showing a first example of a second sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0265] FIG. 18 is a diagram showing a second example of the second sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0266] FIG. 19 is a diagram showing a third example of the second sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0267] 17 to 19 is an example of a screen of the management application executed on the information terminal 3, and is an example of a rice remaining amount reduction screen displayed by touching the rice remaining amount reduction button 215g. The second sub-screen SS2 is displayed as a pop-up so as to overlap the first sub-screen SS1.

[0268] As shown in Figures 17 to 19, the rice cooking system 1 of this embodiment displays the second sub-screen SS2, which is a rice remaining amount reduction screen for reducing the remaining amount of rice, on the display unit 101 in response to a remaining amount reduction operation accepted by the rice remaining amount reduction button 215g.

[0269] When the Reduce Rice Remaining Button 215g on the first sub-screen SS1 is touched, the second sub-screen SS2 pops up and is displayed overlapping the first sub-screen SS1. While the second sub-screen SS2 is displayed, each first sub-display element 215 on the first sub-screen SS1 and each first display element 201 on the first screen WS1 are displayed in gray, for example, in light gray, and do not accept touch operations.

[0270] The second sub-screen SS2 includes a plurality of second sub-display elements 221.

[0271] The multiple second sub-display elements 221 include, for example, from the top of the second sub-screen SS2, a first title string 221a that displays the text "Reduce rice," a second title string 221b that displays the text "Please set the amount of rice you want to reduce," a third title string 221c that displays the text "*1 cup = 150g," a fourth title string 221d that displays the "unit" as a string, a unit switching tab 221e that displays a combination of multiple text strings, such as "kg," "g," and "cup (go)," and multiple separator symbols, such as "|," that separate adjacent text strings, a numerical option 221f that displays multiple numerical values ​​as options arranged vertically so that any one option can be selected, a cancel button 221g that displays the text "cancel," and a decision button 221h that displays the text "decide."

[0272] The first title character string 221a allows the user to easily recognize that the second sub-screen SS2 is a rice remaining amount reduction screen for reducing the amount of rice in stock.

[0273] The second title character string 221b allows the user to easily understand how to use the second sub-screen SS2.

[0274] The third title character string 221c allows the user to easily recognize that one cup (1 gou) is approximately 150 grams (g).

[0275] The fourth title character string 221d allows the user to easily recognize that the character string displayed on the unit switching tab 221e means a unit.

[0276] The unit switching tab 221e lists options for the unit system applied to the numerical value options 221f. When the "kg" tab is selected in the unit switching tab 221e, the numerical value options 221f present options in kilograms, as shown in FIG. 17. When the "g" tab is selected in the unit switching tab 221e, the numerical value options 221f present options in grams, as shown in FIG. 18. When the "cup (go)" tab is selected in the unit switching tab 221e, the numerical value options 221f present options in cups, as shown in FIG. 19.

[0277] The numeric option 221f is a user interface known as a drum roll or picker. The numeric option 221f allows the user to easily recognize selectable options, i.e., the selectable numerical range and the change amount of the options. For example, the selectable numerical range in kilogram units is 1 kilogram to 30 kilograms, and the options in kilogram units are presented in discrete values ​​in 0.5 kilogram increments. For example, the selectable numerical range in gram units is 10 grams to 990 kilograms, and the options in gram units are presented in discrete values ​​in 10 grams. For example, the selectable numerical range in "cup" units is 1 cup to 5 cups, and the options in "cup" units are presented as integer values. The drum roll can be operated by tracing the options in the direction in which the options are arranged, i.e., upward or downward on the display unit 101 in this embodiment, while visually viewing adjacent options that are numerically consecutive. Therefore, the user can select an option while extremely easily grasping the selectable numerical range and the change amount of the options. In addition, the numerical value option 221f has a selectable range of numerical values, i.e., a variable range of quantity, that varies depending on the unit of measurement applied. Therefore, the user can select an option within an appropriate range according to the actual situation for each of the kilogram, gram, and "go" units.

[0278] When the cancel button 221g is touched, the rice inventory stored in the memory unit 107 is maintained regardless of the state of the unit switching tab 221e and the numerical option 221f, and the second sub-screen SS2 closes without any change and the first sub-screen SS1 returns.

[0279] When the decision button 221h is touched, the quantity of rice selected using the unit switching tab 221e and the numerical option 221f is reduced from the rice inventory stored in the memory unit 107, the second sub-screen SS2 closes, and the first sub-screen SS1 returns.

[0280] Next, suppose that the rice remaining amount addition button 215h on the first sub-screen SS1 is touched with the aim of adding to the rice stock amount that the rice cooking system 1 knows about.

[0281] FIG. 20 is a diagram showing a first example of the third sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0282] FIG. 21 is a diagram showing a second example of the third sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0283] FIG. 22 is a diagram showing a third example of the third sub-screen displayed on the display unit of the information terminal according to the embodiment of the present invention.

[0284] 20 to 22 is an example of a screen of the management application executed on the information terminal 3, and is an example of a rice remaining amount addition screen displayed by touching the rice remaining amount addition button 215h. The third sub-screen SS3 is displayed as a pop-up so as to overlap the first sub-screen SS1.

[0285] As shown in Figures 20 to 22, the rice cooking system 1 of this embodiment displays the third sub-screen SS3, which is a rice remaining quantity addition screen for adding remaining rice, on the display unit 101 in response to a remaining quantity addition operation accepted by the rice remaining quantity addition button 215h.

[0286] When the Reduce Rice Remaining Button 215g on the first sub-screen SS1 is touched, the third sub-screen SS3 pops up and is displayed overlapping the first sub-screen SS1. While the third sub-screen SS3 is displayed, each first sub-display element 215 on the first sub-screen SS1 and each first display element 201 on the first screen WS1 are displayed in gray, for example, in light gray, and do not accept touch operations.

[0287] The third sub-screen SS3 includes a plurality of third sub-display elements 225.

[0288] The multiple third sub-display elements 225 include, for example, from the top of the third sub-screen SS3, a first title string 225a that displays the text ``Increase rice,'' a second title string 225b that displays the text ``Please set the amount of rice you want to increase,'' a third title string 225c that displays the text ``*1 cup = 150g,'' a fourth title string 225d that displays the ``unit'' as a string, a unit switching tab 225e that displays a combination of multiple text strings, such as ``kg,'' ``g,'' and ``cup (go),'' and multiple separator symbols, such as ``|,'' that separate adjacent text strings, a numerical option 225f that displays multiple numerical values ​​as options arranged vertically so that any one option can be selected, a cancel button 225g that displays the text ``cancel,'' and a decision button 225h that displays the text ``decide.''

[0289] The first title character string 225a allows the user to easily recognize that the third sub-screen SS3 is a rice remaining amount addition screen for adding rice to the stock amount.

[0290] The second title string 225b, the third title string 225c, the fourth title string 225d, the unit switching tab 225e, the numerical options 225f, the cancel button 225g, and the decide button 225h have the same display and function as the second title string 221b, the third title string 221c, the fourth title string 221d, the unit switching tab 221e, the numerical options 221f, the cancel button 221g, and the decide button 221h displayed on the second sub-screen SS2 shown in Figures 17 to 19, and are intended for the purpose of adding rice inventory.

[0291] 17 to 19 and 20 to 22, the second sub-screen SS2 and the third sub-screen SS3 include numerical value options 221f, 225f as a quantity input section 231 where the quantity related to the remaining amount of rice can be input, and unit switching tabs 221e, 225e as a unit selection section 232 where the unit related to the quantity can be selected. Therefore, the user of the rice cooking system 1 can add or reduce the amount of rice in stock in the unit appropriate for the situation, that is, in the SI units of kilograms or grams, and in the unit of "go (cup)" based on the shakkanho system.

[0292] For example, while it is assumed that rice is often purchased in kilograms or grams at retail stores, even if you occasionally receive new rice in "go" units from an acquaintance, you can add rice to your inventory in the unit appropriate for that occasion without converting units or re-measuring in SI units. Also, for example, even if you consume rice in grams for purposes other than cooking according to a cooking recipe, you can reduce your rice inventory in the unit appropriate for that occasion without converting units or re-measuring in "go" units.

[0293] Furthermore, the appearance of the numerical value options 221f, 225f and the unit switching tabs 221e, 225e is the same on the second sub-screen SS2 and the third sub-screen SS3. In other words, the user interface of the numerical value options 221f, 225f and the unit switching tabs 221e, 225e is the same. Therefore, the user can clearly distinguish whether they are adding or reducing the amount of rice stock by the difference in the screen, that is, the visual difference, and can immerse themselves in the operation without hesitation when inputting the quantity to be increased or decreased.

[0294] It is preferable that the initial unit in the unit switching tab 221e of the second sub-screen SS2 be different from the initial unit in the unit switching tab 225e of the third sub-screen SS3. For example, since it is assumed that rice is often purchased in kilograms at a store, it is preferable that the initial unit in the unit switching tab 225e on the third sub-screen SS3 as the remaining rice amount addition screen be "kilogram." Also, for example, assuming a case where rice is consumed in grams according to a cooking recipe for a purpose other than cooking rice, it is preferable that the initial unit in the unit switching tab 225e on the second sub-screen SS2 as the remaining rice amount reduction screen be "gram." Furthermore, for example, assuming a case where rice is consumed in "go" units according to a cooking recipe for a purpose other than cooking rice, it is preferable that the initial unit in the unit switching tab 225e on the second sub-screen SS2 as the remaining rice amount reduction screen be "cup (go)." In other words, when adding or reducing rice inventory, the rice cooking system 1 instantly presents an interface that allows the user to increase or decrease the rice inventory in units appropriate to the situation, allowing the user to easily immerse themselves in the operation of increasing or decreasing the rice inventory.

[0295] The rice cooker 2 according to this embodiment, configured as described above, heats the pot 25 with the heating coil 31, changing the temperature at the bottom of the pot detected by the pot temperature sensor 46, and determines the amount of cooked rice using multiple methods based on the change in the temperature at the bottom of the pot. As a result, the rice cooker 2 can provide more suitable rice amount determination results for various uses, including rice cooking.

[0296] Furthermore, the rice cooker 2 according to this embodiment executes a first determination method for determining a first determination amount and a second determination method for determining a second determination amount that is more accurate than the first determination amount. Therefore, the rice cooker 2 can perform rice cooking operations according to the amount of cooked rice determined conventionally, i.e., the first determination amount, and can also provide a more appropriate amount of cooked rice for applications requiring a determination result with different accuracy, i.e., the second determination amount, such as rice consumption management or a monitoring function of the rice cooker 2 that relies on rice consumption.

[0297] Furthermore, the rice cooker 2 according to this embodiment determines the amount of cooked rice using a first determination method and a second determination method that both use the pan bottom temperature detected by the pan temperature sensor 46. Therefore, the rice cooker 2 can generally execute multiple determination methods based on the detection results of a conventionally implemented detector, such as the pan temperature sensor 46, without adding an additional detector that detects physical quantities. If the multiple determination methods are implemented as software executed by the rice cooking control unit 97, the rice cooker 2 can execute the multiple determination methods, i.e., the first determination method and the second determination method, with minimal changes to the hardware.

[0298] In the past, rice cooking was often performed using whole-go portions, such as 1 go or 2 go. However, with the rise of individual meals in recent lifestyles, it is not uncommon for rice to be cooked in half-go portions, such as 0.5 go or 1.5 go. Therefore, the rice cooker 2 according to this embodiment executes a second determination method for determining the amount of rice to be cooked using a second determination amount with a larger number of classes than the first determination amount. This allows the rice cooker 2 to more appropriately determine the amount of rice to be cooked, even when cooking rice in finely chopped portions in 0.5 go increments.

[0299] Furthermore, the rice cooker 2 according to this embodiment executes a first determination method and a second determination method that classify the amount of rice to be cooked into multiple levels based on at least one threshold value set for each cooking course. Therefore, the rice cooker 2 can appropriately determine the amount of rice to be cooked even for an item whose heat capacity is significantly different from that of normal rice cooking, such as rice for cooking porridge.

[0300] Furthermore, the rice cooker 2 according to this embodiment executes the first and second determination methods executed in the soaking cooking step of the object to be heated, and the third determination method executed in a step after the soaking cooking step. Therefore, the rice cooker 2 can determine the amount of cooked rice by the third determination method even in a course where it is not appropriate to execute the cooked rice amount determination step in the soaking cooking step, such as the quick cooking course.

[0301] Furthermore, the rice cooker 2 according to this embodiment implements a third determination method that classifies the amount of cooked rice into multiple levels based on the time required for the rice to boil after the temperature at the bottom of the pot detected by the pot temperature sensor 46 reaches a predetermined determination temperature. Therefore, the rice cooker 2 can implement the third determination method without adding an additional detector that detects physical quantities, generally by using the detection results of a conventionally implemented detector, such as the pot temperature sensor 46, and the timing results of a timer built into the rice cooking control unit 97. If the third determination method is implemented as software executed by the rice cooking control unit 97, the rice cooker 2 can implement the third determination method with minimal changes to the hardware.

[0302] Furthermore, the rice cooker 2 according to this embodiment is equipped with a communication module 89 that transmits the second determination amount determined by the second determination method to an external device. Therefore, the rice cooker 2 can provide the rice cooking amount for applications that utilize the determination result of the rice cooking amount outside the rice cooker 2, such as rice consumption amount management or a monitoring function of the rice cooker 2 that relies on the rice consumption amount.

[0303] Furthermore, the rice cooker 2 according to this embodiment transmits the second determination amount used to manage the consumption amount of the cooked food to an external device. Therefore, the rice cooker 2 can provide the user with an environment in which they can easily check the amount of rice in stock, regardless of the physical distance between the rice cooker 2 and the user. In other words, the rice cooker 2 can easily make the user aware of the amount of rice in stock and easily encourage the user to take action to avoid running out of rice.

[0304] Furthermore, the rice cooker 2 according to this embodiment does not transmit the second determination amount to the outside of the machine during the cooking course and maintenance course. Therefore, the rice cooker 2 can reduce the load on the external communication network 12 and the rice cooking system 1 during courses where the determination result of the rice cooking amount does not naturally exist.

[0305] Furthermore, the rice cooker 2 according to this embodiment does not determine the amount of cooked rice during the cooking course and maintenance course. Therefore, the rice cooker 2 can finish courses that do not require time for the unnecessary rice amount determination process at an appropriate time.

[0306] Therefore, the rice cooker 2 according to the present invention can provide a rice cooker that can determine the amount of food to be cooked according to the purpose.

[0307] The rice cooker 2 according to this embodiment can execute the method for determining the amount of cooked rice and the process for determining the amount of cooked rice even when it is used independently, that is, in a so-called stand-alone form, without using a communication function and without being connected to the telecommunications network 11 and the rice cooking system 1. Furthermore, even if the rice cooker 2 does not have the communication function for connecting to the telecommunications network 11 and the rice cooking system 1, it can execute the method for determining the amount of cooked rice and the process for determining the amount of cooked rice.

[0308] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0309] 1...rice cooking system, 2...rice cooker, 3...information terminal, 5...short-range wireless communication, 7...server, 8...storage device, 11...telecommunications network, 12...external communication network, 13...in-house communication network, 15...relay device, 21...pot housing, 23...main body, 25...pot, 25a...main material, 25b...heating element, 26...lid, 27...hinge mechanism, 28...power line, 31...heating coil, 31u...first coil, 31d...second coil, 32...flange portion, 35...bottom plate, 36...upper frame, 37...inner frame, 38...outer frame, 39...controller housing chamber, 41...vent, 42...heating control circuit board, 43...radiator, 45...cooling fan, 46...pot temperature sensor Servo, 51... hinge shaft, 52... hinge spring, 55... outer lid, 56... outer lid cover, 57... heat sink, 58... lid heater, 59... inner lid unit, 61... inner lid, 62... lid gasket, 63... gasket base, 65... steam vent, 66... ​​steam exhaust passage, 67... pressure regulating valve, 67a... valve body, 67b... solenoid, 68... pressure reducing pump, 69... pressure reducing hole, 71... lid opening operation button, 72... lid lock mechanism, 73... operation panel, 75... input / output control circuit board, 76... display unit, 77... operation unit, 81... coil drive circuit, 81u... first drive circuit, 81d... second drive circuit, 83... lid heater drive circuit, 8 5...lid temperature sensor, 86...lid opening / closing sensor, 87...pressure sensor, 88...alarm unit, 89...communication module, 92...input signal generation unit, 93...display control unit, 95...condition setting unit, 97...rice cooking control unit, 98...keep warm control unit, 101...display unit, 102...input device, 102a...touch panel, 102b...voice input unit, 103...communication module, 105...terminal control unit, 107...memory unit, 108...communication control function, 109...display control function, 111...communication module, 201...first display element, 201a...model identification character string, 201b...setting screen call icon, 201c...support screen screen call icon, 201d...model icon, 201e...status display string, 201f...brand name send button, 201g...rice remaining amount adjustment button, 201h...rice cooking history call button, 201i...course introduction call button, 201j...background, 201k...first title string, 201m...brand name send screen call icon, 201n...second title string, 201o...stock amount string, 201p...rice remaining amount adjustment input section call icon, 211...additional input section, 212...reduction input section, 215...first sub-display element, 215a...first title, 215b...button, 215c...stock amount string, 215e...stock amount annotation area,215f...second title string, 215g...reduce remaining rice amount button, 215h...add remaining rice amount button, 215i...reduction annotation string, 215j...addition annotation string, 215k...notification string, 221...second sub-display element, 221a...first title string, 221b...second title string, 221c...third title string, 221d...fourth title string, 221e...unit switching tab, 221f...numerical options, 221g...cancel button, 221h...decision button, 225...third sub-display element, 225a...first title string, 225b...second title string, 225c...third title string, 225d...fourth title string, 225e...unit switching tab, 225f...numerical options, 225g...cancel button, 225h...decision button, 231...quantity input section, 232...unit selection section.

Claims

1. a pot for containing food to be cooked; A heating unit that heats the pot; a temperature detection unit that detects the temperature of the pot; a control unit that controls the heating unit, The control unit The rice cooker heats the pot with the heating unit, changing the temperature of the pot detected by the temperature detection unit, and determines the amount of the food being cooked based on the change in temperature using multiple determination methods.

2. The plurality of determination methods include: a first determination method for determining a first determination amount; and a second determination method for determining a second determination quantity having a higher determination accuracy than the first determination quantity.

3. The rice cooker according to claim 2 , wherein the first determination method and the second determination method commonly use the temperature detected by the temperature detection unit.

4. The first and second determination methods determine the amount of the food to be cooked into a plurality of classes, The rice cooker according to claim 2 or 3, wherein the number of classes of the second determination amount is greater than the number of classes of the first determination amount.

5. The control unit can execute a plurality of cooking courses each having a different type of food to be cooked and a different cooking method, The rice cooker according to claim 2 , wherein the first determination method and the second determination method determine the amount of the cooked rice into a plurality of levels based on at least one threshold value set for each of the rice cooking courses.

6. The control unit can execute a plurality of cooking courses each having a different type of food to be cooked and a different cooking method, The plurality of determination methods include: The first determination method and the second determination method executed in the soaking cooking process of the object to be heated; and a third determination method that is executed in a step subsequent to the soaking step.

7. The rice cooker according to claim 6, wherein the third determination method determines the amount of the food to be cooked into multiple classes based on the time required for the food to boil after the temperature of the pot detected by the temperature detection unit reaches a predetermined determination temperature.

8. The rice cooker according to claim 2 , further comprising a transmitter that transmits the second determination amount determined by the control unit to an outside of the rice cooker.

9. The rice cooker according to claim 8, wherein the second determination amount is used to manage consumption of the food to be cooked.

10. The control unit is capable of executing cooking courses other than the rice cooking course and a maintenance course for maintaining the appliance, The rice cooker according to claim 8 , wherein the transmitter does not transmit the second determination amount to the outside of the rice cooker during the cooking course and the maintenance course.

11. The rice cooker according to claim 1 or 2, wherein the control unit is capable of executing cooking courses other than the rice cooking course and a maintenance course for maintaining the appliance, and the amount of the food being cooked is not determined in the cooking course and the maintenance course.

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