Rice cooker

Abstract

To provide a rice cooker capable of selectively cooking rice according to the information of rice such as the kind of the kind brand of the production area of rice, the milling degree of rice and a storage period after rice milling.SOLUTION: This rice cooker 100 is provided with a rice cooking control means 51 for controlling a rice cooking process for cooking rice and water, a display means 18 for selectably displaying the setting of the information of the rice for selecting the information of the rice such as the brand of the rice, the milling degree of the rice and a storage period after milling the rice and an operation means 19 capable of selectively operating the information of the rice displayed at the display means 18. The soaking and boiling process includes a soaking process of soaking rice in unheated water and an enzymatic activity process of soaking rice in heated water by increasing the temperature of rice to be cooked after the soaking process, and the rice cooking control means 51 is configured to perform control according to the time T1 of the soaking process corresponding to the setting of information on the selected rice.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a rice cooker that has a soaking process that promotes water absorption by rice during rice cooking control. [Background technology]

[0002] Conventionally, as an example of this type of rice cooker, Patent Document 1 discloses a soaking process in which, when rice cooking begins, the rice is soaked for about 15 minutes without heating the inner pot (31) to reduce the moisture content of the rice to nearly 30%, and after the soaking process, a water absorption and gelatinization process is carried out in which the inner pot (31) is heated using a sheath heater (12) to increase the temperature of the water to be cooked to nearly 60°C, and the rice absorbs water while gelatinizing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-213413 Summary of the Invention [Problem to be solved by the invention]

[0004] It is known that the water absorption rate of rice varies depending on the type of rice, variety, and brand, the rice's production area, the degree of pounding, the storage period after milling, etc. However, in Patent Document 1, the soaking time is uniform and is not changed depending on the rice variety or production area, etc., so it may not be possible to cook rice differently depending on the type of rice, variety, and brand, the rice's production area, the degree of pounding, the storage period after milling, etc.

[0005] In view of the above circumstances, the present invention aims to provide a rice cooker that can cook rice in different ways depending on rice information such as the type of rice growing area, variety, and brand, the degree of polishing, and the storage period after polishing. [Means for solving the problem]

[0006] The rice cooker of the present invention is equipped with a control means for controlling the rice cooking process in which rice and water are cooked, and a selection means for selecting information about the rice.The rice cooking process includes a soaking process in which the rice is soaked in unheated water to promote water absorption by the rice.The soaking process includes a soaking process in which the rice is soaked in unheated water, and an enzyme activation process in which the temperature of the food to be cooked is raised and the rice is soaked in the heated water after the soaking process.The control means controls the soaking process time according to the selected information about the rice. [Effects of the Invention]

[0007] According to the rice cooker of the present invention, rice can be cooked differently depending on the rice information. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view of a rice cooker showing a first embodiment of the present invention. [Figure 2] FIG. [Figure 3] 1A and 1B are a cross-sectional view and a plan view from the bottom side of the inner frame and the heating coil, respectively. [Figure 4] FIG. 2 is a block diagram showing the electrical configuration of the rice cooker. [Figure 5] FIG. 1 is an explanatory diagram showing an overview of the rice cooking system. [Figure 6] This is a top view of the LCD displaying the rice cooking / keep warm screen. [Figure 7] FIG. 10 is an explanatory diagram showing how to display the first process display area in the same as above. [Figure 8] FIG. 10 is an explanatory diagram showing how the cooking time display is displayed. [Figure 9] 10 is a graph showing the change over time in the temperature of the pot, the output of the heating coil, and the output of the vacuum pump during the rice cooking process and the keep-warm process. [Figure 10]This is a graph showing the change in pot temperature over time of a conventional rice cooker and the change in pot temperature over time of the rice cooker of this embodiment, by amount of food being cooked, during the capacity determination process of the soaking cooking process. [Figure 11] FIG. 3 is a block diagram showing the electrical configuration of a rice cooker showing a modified example of the first embodiment of the present invention. [Figure 12] 10 is a graph showing the change over time in the temperature of the pot, the output of the heating coil, the output of the cooling means, and the output of the vacuum pump during the rice cooking process and the keeping-warm process. [Figure 13] FIG. 10 is a diagram showing the change over time in the water level and rice height in the pot, starting from the point when polished rice in the rice cooker according to the second embodiment of the present invention is washed with water and the water level in the pot is adjusted using the washed water. [Figure 14] FIG. 2 is a block diagram showing the electrical configuration of the rice cooker. [Figure 15] As above, this is a table showing the relationship between the temperature of the water in the pot, the time it takes for the water level and rice height in the pot to stabilize, the specified temperature in the enzyme activation process, the output of the heating coil in the rice cooking process, the time for the steaming process, and the keeping-warm temperature in the keeping-warm process. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, preferred embodiments of the rice cooker of the present invention will be described with reference to the accompanying drawings. Note that common parts will be designated by common reference numerals throughout these drawings. [Example]

[0010] FIGS. 1 to 10 show a first embodiment of a rice cooker 100 according to the present invention. First, the overall configuration of rice cooker 100 will be described with reference to FIGS. 1 and 2. Reference numeral 1 denotes a main body, which, when viewed from above, has a generally rectangular shape with a front, rear, left, and right sides facing each other, and an open top. Reference numeral 2 denotes a lid that can be opened and closed to cover the top opening of main body 1. Similar to main body 1, lid 2 also has a generally rectangular shape with a front, rear, left, and right sides facing each other, and an approximately flat top. Main body 1 has a pot housing 3 with an open top. When lid 2 is opened, a bottomed pot 4, which serves as a container for water and rice to be cooked, is removably housed in pot housing 3. Pot housing 3 is constructed by combining a bowl-shaped resin inner frame 5 and other components, and the overall shape is cylindrical with a bottom.

[0011] Pot 4 has a main material 7 made of aluminum, which has good thermal conductivity, and a heating element 8 made of a magnetic metal plate such as ferritic stainless steel, bonded to the outer surface of main material 7 from the lower side to the bottom. Additionally, on the outer surface of inner frame 5, which faces the lower side of pot 4 toward the bottom, a heating coil 11 is provided as a heating means for electromagnetic induction heating of heating element 8 of pot 4. When high-frequency current is supplied to heating coil 11, the alternating magnetic field generated by heating coil 11 causes heating element 8 of pot 4 to heat, heating the food inside pot 4 during cooking and keeping warm. Heating coil 11 will be explained in more detail later. A pot sensor 12, which serves as a pot temperature detection means, is located in the center of the bottom of inner frame 5 so that it makes elastic contact with the outer bottom surface of pot 4.

[0012] A hinge 13 is provided at the rear of the lid 2, which connects it to the main body 1. A lid operating body 14 is provided in an exposed state on the front upper surface of the lid 2, and when the lid operating body 14 is pressed, the engagement between the main body 1 and the lid 2 is released, and a hinge spring (not shown) provided at the upper rear of the main body 1 causes the lid 2 to open, with the hinge axis of the hinge 13 as the center of rotation.

[0013] A steam vent 15 is provided on the upper rear surface of the lid 2, which exhausts steam generated from the food being cooked in the pot 4 to the outside of the rice cooker 100. In addition to the steam vent 15 and the lid operating mechanism 14, the upper surface of the lid 2 is also provided with a display means 18 consisting of an LCD (Liquid Crystal Display) 16 as a screen display unit and an LED (Light Emitting Diode) display 17 as a status display unit for displaying various information related to rice cooking, and an operating means 19 consisting of a touch sensor and located above the LCD 16 for starting rice cooking and selecting the time and cooking course. A control PC (Printed Circuit) board 21 is also located on the underside of the display means 18 and operating means 19.

[0014] The LED display 17 displays the actual status of the rice cooker 100. In this embodiment, the "RESERVED" LED indicator lights when a timer is set, the "KEEP WARM" LED indicator lights when the rice cooker is in the KEEP WARM state, the "VACUUM" LED indicator lights when the pressure inside the pot 4 is reduced below atmospheric pressure by the pressure reducing means 38 (described later), and the "PRESSURE" LED indicator lights when the pressure inside the pot 4 is increased from the time pressure inside the pot 4 begins to build up during cooking until the rice is cooked. Therefore, even when the backlight of the LCD 16 is dimmed, the user can check the LED display 17 to understand the current status of the rice cooker 100 at a glance. In this embodiment, the LED display 17 is located directly in front of the LCD 16, but it may also be located away from the LCD 16. Alternatively, the LED display 17 may be omitted, and the display contents of the LED display 17 may be displayed on the LCD 16.

[0015] The operating means 19, which is composed of a touch sensor, is configured such that a plurality of components are arranged as touch keys, each of which is connected by pattern wiring between a transparent electrode section made of a conductive polymer and a contact section connected to the control PC board 21, and by performing a touch operation on one of a plurality of button display sections displayed on the LCD 16, the touch key arranged above that button display section and corresponding to that button display section is touched and that button display section is selected.

[0016] In this way, taking into consideration user operability and safety, lid operating member 14 is located on the front of the top surface of rice cooker 100, closer to the user, and steam vent 15 is located on the rear of the top surface of rice cooker 100, farther from the user. This allows for ample space on the top surface of lid 2 between lid operating member 14 and steam vent 15 for display means 18. This allows for larger display means 18 and operating means 19 located above it, improving the visibility of display means 18 and the operability of operating means 19. Furthermore, apart from operating means 19 above LCD 16, the top surface of lid 2 does not contain any operating means, such as physical keys and buttons like a rice cooker key or an off key, as found on conventional rice cookers. Operating rice cooker 100 can be performed using operating means 19 alone, eliminating the need to search for buttons and improving operability. This also results in a very sleek appearance, and allows for a compact space for display means 18 and operating means 19, which are precision components. In addition, by removing the physical keys and buttons, the top surface of the cover 2 can be made approximately flat, making it easier to wipe and clean, improving cleanability.

[0017] An inner lid assembly 23 is disposed below the lid 2 and serves as the lower component of the lid 2. The inner lid assembly 23 is made of a metal material and has a disk shape with approximately the same diameter as the upper opening of the pot 4. The inner lid assembly 23 includes an inner lid 24 that covers the upper opening of the pot 4, a lid gasket 25 as an elastic member provided around the entire outer periphery of the inner lid 24 to seal the gap between the inner lid 24 and the pot 4, and a pressure regulator 26 that adjusts the internal pressure of the pot 4. The annular lid gasket 25 abuts against the top surface, which is the opening of the pot 4, when the lid 2 is closed as shown in FIG. 2, to close the gap between the pot 4 and the inner lid 24 and seal out steam generated from the pot 4.

[0018] Lid opening / closing detection means 27 is provided inside lid 2 near hinge 13 to detect whether lid 2 is open or closed. Lid opening / closing detection means 27 may be optical, mechanical, magnetic, or any other type of detection system as long as it can output a detection signal in response to the opening or closing of lid 2. Also provided inside lid 2 are lid heater 31 as lid heating means for heating inner lid 24 and a thermistor-type lid temperature sensor 32 for controlling the temperature of inner lid 24 using lid heater 31. Also formed inside lid 2 is steam exhaust path 33 that connects steam vent 15 and pressure adjustment unit 26 and serves as a passageway for releasing steam generated in pot 4 to the outside.

[0019] Pressure adjustment unit 26 is provided with a pressure adjustment valve 34 that opens and closes steam exhaust path 33 between the inside of pot 4 and steam vent 15. Pressure adjustment valve 34 is ball-shaped and operates in conjunction with a solenoid 35 provided inside lid 2. Solenoid 35 rotates pressure adjustment valve 34 to open steam exhaust path 33 when steam inside pot 4 is to be released to the outside and to close steam exhaust path 33 when the pressure inside pot 4 is to be pressurized or reduced. When pressurizing, high-frequency current is applied to heating coil 11 to heat the food inside pot 4, causing the food to boil and generate steam. This steam fills pot 4, and when the internal pressure of pot 4 reaches a predetermined value, pressure adjustment valve 34 opens steam exhaust path 33 against its own weight, thereby maintaining the pressure inside pot 4 at or above atmospheric pressure. A pressure sensor 36 (see FIG. 4) is provided inside lid 2 facing pressure adjustment unit 26 to detect the pressure inside pot 4.

[0020] Reference numeral 38 denotes a pressure reducing means for lowering the pressure inside pot 4 below normal atmospheric pressure when lid 2 is closed on main body 1. After pot 4 is placed in pot holder 3 and lid 2 is closed, pressure reducing means 38 reduces the internal pressure of sealed pot 4 by energizing solenoid 35 and closing pressure regulator valve 34 to block steam exhaust path 33. When the pressure inside pot 4 drops below atmospheric pressure by a certain value, pressure reducing pump 39, which powers pressure reducing means 38, stops operating, maintaining the inside of pot 4 at a reduced pressure. Furthermore, when the pressure inside pot 4 is to be restored from the reduced pressure state to the same pressure as the outside air, pressure reducing pump 39 stops operating and a path (not shown) connecting pressure reducing pump 39 to the inside of pot 4 is opened. In other words, pressure reducing means 38 also serves as a pressure return means for restoring the inside of pot 4 from the reduced pressure state to the same pressure as the outside air.

[0021] Additionally, a unitized heating board assembly 42 including control means 41 is disposed inside main body 1. Control means 41 is configured to electrically control each part of rice cooker 100 and is equipped with a control IC 43 constituting a microcomputer, storage means 44 (see FIG. 4) such as a readable and writable memory that stores various information and data, and timing means 45 (see FIG. 4) such as a timer that can measure the time related to cooking rice. In particular, control means 41 is configured to control the temperature of the bottom of pot 4 mainly by controlling heating coil 11 based on the temperature detected by pot sensor 12, and to control the temperature of inner lid 24, which faces the food to be cooked, mainly by controlling lid heater 31 based on the temperature detected by lid temperature sensor 32.

[0022] FIG. 3 shows a cross-sectional view and a plan view from the bottom side of the inner frame 5 and heating coil 11. Referring to FIG. 3, heating coil 11 in this embodiment is comprised of a side coil 11-1 as a first coil and a bottom coil 11-2 as a second coil. Side coil 11-1 and bottom coil 11-2 are each provided on the outer surface of inner frame 5, i.e., the outer surface of pot accommodating section 3, facing pot 4. Specifically, when pot 4 is accommodated in pot accommodating section 3, bottom coil 11-2 is disposed as a bottom heater facing the outer surface of the bottom of pot 4, and side coil 11-1 is disposed as a lower-side heater outside and above bottom coil 11-2, facing the outer surface of the lower side of pot 4. In this embodiment, the maximum output of the heating coil 11 is, for example, 1400 W for both the side coil 11-1 and the bottom coil 11-2, but these values ​​are merely examples, and the output balance between the side coil 11-1 and the bottom coil 11-2 may be set as desired depending on the heating characteristics of the rice cooker. In this embodiment, the heating coil 11 is composed of two heating coils, but the present invention is not limited to this and may be composed of more heating coils. In this case, each heating coil is arranged concentrically facing from the bottom to the lower side of the pot 4, and multiple heating coils are arranged vertically. Furthermore, the side coil 11-1 and the bottom coil 11-2 may each be individually formed in a spiral shape or in a concentric circular shape, and there are no particular restrictions on the shape of each heating coil.

[0023] Here, we will explain how heat transfers when the heating coil 11 is activated. When the side coil 11-1 is energized, the outer surface of the lower side of the pot 4, which faces the side coil 11-1, first becomes hot. This heat then transfers via the main material 7 to the water in the food being cooked that is in contact with the lower side. Heat transfer to the food occurs primarily along with the water. However, where rice is present, the water movement is limited to the narrow gaps between the rice grains, slowing the transfer of water and heat. On the other hand, where rice is not present, convection promotes the transfer of water and heat. Therefore, the water in the upper part of the food, where rice is not present because it sinks to the bottom, becomes hotter after the water in the lower part of the food being cooked that is in contact with the side. Then, in the center of the food being cooked, the water and heat from the upper part of the food, which has become hotter, moves to the middle part of the food, which is colder, and then to the lower part of the food being cooked. This phenomenon is known as thermal convection, and in this embodiment, it is described as external convection.

[0024] When the bottom coil 11-2 is energized, the outer surface of the bottom of the pot 4, which faces the bottom coil 11-2, first becomes hot, and this heat is transferred via the main material 7 to the water in the food being cooked that is in contact with the bottom. Here, because the rice in the lower part of the food is submerged, the upper part of the lower part is covered with the rice and water, and the temperature and pressure of this water rise. Then, the water in the lower part, whose temperature and pressure have increased, moves upward through the gaps between the rice grains and is blown upward. As a result, the water whose temperature has risen in the lower part, i.e., the hot water, moves together with the heat to the middle part of the food, and then to the upper part. This phenomenon is known as blowing up, and in this embodiment it is described as internal convection.

[0025] Therefore, when electricity is alternately applied to the side coil 11-1 and the bottom coil 11-2, external and internal convection of heat occurs alternately in the food being cooked in the pot 4, which promotes stirring of the water in the food being cooked in the pot 4 and reduces uneven heating.

[0026] 4 shows the electrical configuration of the rice cooker of this embodiment. In the figure, the input port of the control means 41 is electrically connected to the aforementioned pot sensor 12, lid temperature sensor 32, pressure sensor 36, lid open / close detection means 27, and operation means 19, as well as to a transmitting / receiving means 49. The output port of the control means 41 is electrically connected to the aforementioned solenoid 35, pressure reducing pump 39, and display means 18, as well as to a side coil driving means 46 connected to the side coil 11-1, a bottom coil driving means 47 connected to the bottom coil 11-2, and a lid heater driving means 48 connected to the lid heater 31.

[0027] The transmitting / receiving means 49 enables the sending and receiving of information to and from an information terminal 62 held by a user via communication means 61, such as a wired or wireless network. The information terminal 62, which serves as an external terminal that serves as a remote control, is configured as, for example, a smartphone or tablet terminal separate from the rice cooker 100, and, like the display unit 61 of the rice cooker 100, mainly includes a display unit 63 that enables a screen display such as an LCD, and an operation unit 64 using a touch sensor provided on the surface of the display unit 63. An information processing program, such as an application program, is stored in the storage medium of the information terminal 62, and the information processing program is activated to function, thereby transmitting and receiving information to and from the transmitting / receiving means 49 via the communication means 62.

[0028] Side coil driving means 46 receives a heating control signal from control means 41 and supplies a high-frequency current to side coil 11-1 to energize it, while bottom coil driving means 47 receives a heating control signal from control means 41 and supplies a high-frequency current to bottom coil 11-2 to energize it. These side coil driving means 46 and bottom coil driving means 47 are configured with, for example, a power supply circuit, an inverter, an IH driving circuit, and switch elements, and can increase or decrease the output from side coil 11-1 and bottom coil 11-2 to pot 4 by changing the cycle of the high-frequency current supplied to side coil 11-1 and bottom coil 11-2 or the ratio of ON time per cycle (ON ratio). Lid heater driving means 48 receives a heating control signal from control means 41 and supplies DC or AC current to lid heater 31 to drive it. In this embodiment, an example is described in which the current supplied to the side coil 11-1 and the bottom coil 11-2 is selectively switched by a switch element, but the present invention is not limited to this and may include a period in which the side coil 11-1 and the bottom coil 11-2 are simultaneously energized.

[0029] The control means 41 receives operation signals from the operation means 19, information from the transmission / reception means 49, temperature detection signals from the pot sensor 12 and lid temperature sensor 32, pressure detection signals from the pressure sensor 36, and detection signals from the lid opening / closing detection means 27, and outputs a display control signal to the display means 18. It also outputs heating control signals to side coil driving means 46 and bottom coil driving means 47 which energize the side coil 11-1 and bottom coil 11-2 of the heating coil 11, and to the lid heater driving means 48 which drives the lid heater 31, and outputs drive control signals to the solenoid 35 which operates the pressure regulating valve 34 and the pressure reducing pump 39 of the pressure reducing means 38. The control means 41 has rice cooking control means 51, keep-warm control means 52, and display control means 53 in the control IC 43 as functions in the control sequence of the program read out from the storage means 44.

[0030] The rice cooking control means 51, upon receiving a command to start rice cooking from the operating means 19, performs a rice cooking process that sequentially executes a soaking process to promote the absorption of water by the rice placed in the pot 4, a boiling heating process that quickly raises the temperature of the food to boiling, a boiling continuation heating process that keeps the food boiling, and a soaking process that maintains the rice at a high temperature without burning it, and controls rice cooking by heating the food in the pot 4 at a desired pressure. The keep-warm control means 52 also performs a keep-warm process that controls the rice in the pot 4 to maintain a predetermined keep-warm temperature. The display control means 49 generates various control signals based on the operating signal from the operating means 19 and controls the display operation of the display means 18.

[0031] The memory means 44 stores rice cooking courses corresponding to, for example, each rice setting, cooking method setting, hardness setting, etc., and the rice setting, cooking method setting, hardness setting, etc. of the rice cooking course stored in the memory means 44 are displayed selectably on the display means 18, and the rice cooking course is selected and set by selecting and setting these using the operation means 19. The memory means 44 also stores a plurality of heating patterns, which are patterns for driving the heating coil 11, lid heater 31, pressure regulating valve 34, and pressure reducing means 38, i.e., at what timing and output the heating coil 11, lid heater 31, pressure regulating valve 34, and pressure reducing means 38 are driven, and power supply patterns, which are patterns for supplying power to the side coil 11-1 and bottom coil 11-2, i.e., at what timing and output power the side coil 11-1 and bottom coil 11-2 are energized when the heating coil 11 is driven.The rice cooking control means 51 and keep-warm control means 52 control the heating coil 11, lid heater 31, pressure regulating valve 34, and pressure reducing means 38 using these heating patterns and power supply patterns.

[0032] The current pattern in this embodiment is a pattern that includes the current conduction time and output of the side coil 11-1 and the bottom coil 11-2. For example, the side coil 11-1 is energized with output W1 and current conduction time T1, and then the coil is switched and the bottom coil 11-2 is energized with output W2 and current conduction time T2, and this is repeated for a predetermined period. Note that the current conduction pattern also includes one in which only one of the current conduction time and output of the coil is varied while the other is kept constant. For example, this includes a case in which the current conduction time is constant among multiple coils but the output differs among each coil, or a case in which the output is constant among multiple coils but the current conduction time differs among each coil.

[0033] Here, "switching the current conduction pattern" means switching the current conduction pattern itself. For example, in the above example, this means switching from a current conduction pattern in which the side coil 11-1 is energized with output W1 and current conduction time T1, and then the bottom coil 11-2 is energized with output W2 and current conduction time T2, to a current conduction pattern in which, at a predetermined timing, the side coil 11-1 is energized with output W3 and current conduction time T3, and then the bottom coil 11-2 is energized with output W4 and current conduction time T4, and this is repeated.

[0034] The energization pattern may include a switching time during which all coils are turned off when the coils are switched. That is, the energization pattern may be such that one coil is energized for a predetermined energization time and output → switching time 1 → the other coil is energized for a predetermined energization time and output → switching time 2, and this cycle is repeated. Here, switching time 1 and switching time 2 may be the same time or different times.

[0035] The energization time and output of the side coil 11-1 and bottom coil 11-2 in each energization pattern may be values ​​determined by the inventors through extensive experiments, etc. For example, it is preferable that the energization time of the side coil 11-1 and bottom coil 11-2 is several seconds or more, respectively, which causes external and internal convection of heat to occur alternately in the food to be cooked in the pot 4 for a predetermined period of time or more, promoting the stirring of the water in the food to be cooked in the pot 4 and reducing uneven heating.

[0036] The inventors of the present invention have also found that it is preferable that the time for generating external convection and internal convection is not the same in current conduction pattern 1. In other words, it is preferable that the current conduction times for side coil 11-1 and bottom coil 11-2 are not the same in current conduction pattern 1, and that the current conduction times for the switched coils are different before and after coil switching during repetition.

[0037] In addition, in the heat retention process, as will be described later, there is also a current pattern in which one coil is energized while the other coil is not energized. In this current pattern, one coil is energized for a predetermined time and output, and then the coil is de-energized for a predetermined time, and this cycle is repeated.

[0038] Figure 5 shows a schematic diagram of the overall configuration of a rice cooker system including a rice cooker 100 according to this embodiment. In the figure, the rice cooker 100 installed in a house R is capable of transmitting and receiving information to and from a server 101 on the cloud via communication means 61 such as the Internet, and is also configured to be able to remotely display information about the rice cooker 100 on a display unit 63 of an information terminal 62. In this embodiment, the transmitting and receiving means 49 of the rice cooker 100 is configured to exchange various types of data with the server 101 connected to the transmitting and receiving means 49 via the communication means 61, in addition to the information terminal 62.

[0039] Server 101 stores information about rice cooking, such as information about all rice cooking courses. In addition, the transmitting / receiving means 49 of rice cooker 100 and server 101 are configured to be able to transmit and receive information about rice cooking via communication means 61, such as information about rice cooking courses depending on rice settings, such as the brand of rice, the pounding precision of the rice, and the storage period after milling, and water settings, such as water quality information, such as water hardness.

[0040] The operation of the rice cooker system configured as described above will now be described. When an application (not shown) serving as an information processing program is launched on information terminal 62, a signal is sent to transmission / reception means 49 of rice cooker 100 via communication means 61. When transmission / reception means 49 of rice cooker 100 receives this signal, control means 41 of rice cooker 100 sends information about the current rice cooking course to information terminal 62 via communication means 61. When information terminal 62 receives this information, information about the current rice cooking course of rice cooker 100 is remotely displayed on display means 63 of information terminal 62.

[0041] Here, when the operation means 64 of the information terminal 62 is used to select and send information on rice cooking course settings such as the brand of rice, the rice milling precision, the storage period for rice after milling, and water quality information, or information on reserved cooking settings, this information is sent to the server 101 via the communication means 61. When the server 101 receives this information, it sends information on the rice cooking course and reserved cooking corresponding to this information to the rice cooker 100 via the communication means 61. Upon receiving this information, the control means 41 of the rice cooker 100 stores the received rice cooking course and reserved cooking information as the current rice cooking course in the storage means 44. If this information is reserved cooking, reserved cooking will begin in the rice cooker 100, and if this information is a rice cooking course, the rice cooker 100 will be ready to start cooking if an instruction to start cooking is given.

[0042] In this embodiment, after the control means 41 sends a signal permitting remote-controlled rice cooking, the control means 41 sends information about the current rice cooking course, such as the rice brand, rice milling accuracy, storage period after milling, and water quality information, to the information terminal 62 via the communication means 61. By launching an information processing program on the information terminal 62, it is possible to remotely display and remotely control the rice cooking course settings of the rice cooker 100 on the display unit 63 of the information terminal 62. Therefore, even if the user is in a location far from the rice cooker 100, the user can set the rice cooking course of the rice cooker 100 and know the estimated time for rice cooking to be completed by displaying the required cooking time, which is the time required for the rice cooking process.

[0043] In this embodiment, the transmitting / receiving means 49 of the information terminal 62 and the rice cooker 100 are both connected to a network that serves as the communication means 61, and are configured to be able to transmit and receive data to and from each other via that network, but this is just one example, and the information terminal 62 and the rice cooker 100 may also be configured to be able to transmit and receive data directly via the communication means 61. Furthermore, instead of the information terminal 62, a device that is installed indoors or otherwise connectable to a network, such as a personal computer, may be used as an external terminal.

[0044] 6 shows a top view of LCD 16, and the upper side of each drawing will be referred to as "top," the lower side as "bottom," the left side as "left," and the right side as "right." In the figure, LCD 16 is displaying rice cooking / keeping warm screen G1, and when the user selects and operates operation means 19 to start cooking the food, display control means 53 causes LCD 16 to display the rice cooking / keeping warm screen G1 layout as shown in FIG. 6 as the screen to be displayed on LCD 16 during the rice cooking process and the keep warm process.

[0045] The rice cooking / keep-warm screen G1 will be explained with reference to Figure 6. At the top of the screen, a first process display area A1 is formed with three lamp indicators D1 to D3 lined up horizontally. More specifically, with reference to Figure 7, the following lamp indicators are lined up horizontally in order to display the process currently being performed by the rice cooker 100: standby process lamp indicator D1, which lights up as shown in (A) to indicate that the current process is a standby process before moving on to the rice cooking process in the scheduled rice cooking; heating process lamp indicator D2, which flashes as shown in (B) to indicate that the current process is the soaking process in the rice cooking process and lights up as shown in (C) to indicate that the current process is the boiling and heating process or the continuous boiling process in the rice cooking process; and soaking / keep-warm process lamp indicator D3, which flashes as shown in (D) to indicate that the current process is the soaking process in the rice cooking process and lights up as shown in (E) to indicate that the current process is the keep-warm process.

[0046] Returning to Figure 6, below the first process display area A1, a second process display area A2 is formed, with process indicators D4 to D8 arranged side by side. Here, the process indicator D4 for "standby" includes the text "standby." Similarly, the process indicator D5 for "soaking" includes the text "soaking," the process indicator D6 for "cooking rice" includes the text "cooking rice," the process indicator D7 for "steaming" includes the text "steaming," and the process indicator D8 for "keeping warm" includes the text "keeping warm."

[0047] The process indicators D4 to D8 display the processes that the rice cooker 100 will carry out or the process that is currently being carried out. In this embodiment, the display control means 53 controls the LCD 16 so that the process indicators D4 to D8 corresponding to processes that the rice cooker 100 will not carry out or processes that have been carried out are not displayed, but the cursor C (not shown) is positioned on the process indicators D4 to D8 corresponding to the process that the rice cooker 100 is currently carrying out and displayed in white letters, and the process indicators D4 to D8 corresponding to the processes that the rice cooker 100 will carry out are displayed.

[0048] Below the second process display area A2, there is a time display area A3 that displays the current time and the remaining time in the rice cooking process. Specifically, on the left side of the time display area A3, a "clock" text display D11, which suggests that the numbers displayed on the time display D12 are the current time, and a time display D12 that displays the current time are arranged vertically. On the right side of the time display area A3, there are a cooking time text display D13, which suggests that the numbers displayed on the cooking time display D14 are times related to cooking completion, and a cooking time display D14 that displays the cooking completion time, which is the estimated time when rice cooking will be completed, arranged vertically. The cooking time text display D13 currently displays the text "Cooking completion time," suggesting to people looking at the time display area A3 that the numbers displayed on the cooking time display D14 are the cooking completion time, which is the time when rice cooking will be completed. As shown in FIG. 8, each time the time adjustment button display B15 (described later) is touched, the display control means 53 controls the LCD 16 to change the display of the cooking time display D14 in the following order: (A) cooking time → (B) cooking time, which is the time required for the cooking process in the current cooking course setting → (C) remaining cooking time, which is the time until the cooking process is completed → (A) cooking time. Accordingly, the display control means 53 controls the LCD 16 to change the display of the cooking time text display D13 in the following order: (A) "cooking time" → (B) cooking time → (C) remaining cooking time → (A) "cooking time", as shown in FIG. 8.

[0049] In this embodiment, the first step display area A1, the second step display area A2, and the time display area A3 function as display means for displaying various information related to rice cooking. The second step display area A2 and the time display area A3 are displayed within a rectangular frame 71, which functions as status display means for displaying the status of the rice cooker 1.

[0050] Returning to FIG. 6, a time adjustment display area A4 is formed on the right side of the frame 71, allowing adjustment of the time display D12 and the cooking completion time display D14. Specifically, in the time adjustment display area A4, a time adjustment button display B15, a value increase button display B16, and a value decrease button display B17 are arranged vertically. The time adjustment button display B15 includes a clock mark display D15 displaying a clock mark. Similarly, the value increase button display B16 includes a "▲" mark display D16, and the value decrease button display B17 includes a "▼" mark display D17.

[0051] The time adjustment button display B15, the value increase button display B16, and the value decrease button display B17 are operated to adjust the display on the time display D12 and the display on the cooking time display D14. For example, when the time adjustment button display B15 is touched to set the time for scheduled cooking, the control means 51 receives an operation signal from the operation means 29 arranged over the time adjustment button display B15, and the display control means 53 controls the LCD16 to change the display on the cooking time text display D13 and the cooking time display D14, as described above. Also, when the time adjustment button display B15 is pressed and held, for example, the display control means 53 controls the LCD16 to flash the time display D12, thereby notifying the user that the display on the time display D12 can be changed. Here, when the numeric value increase button display B16 or the numeric value decrease button display B17 is touched, the display control means 53 controls the LCD 16 to change the display of the blinking display, for example, the cooking time display D14, to correspond to the touched button display.

[0052] At the bottom left of the rice cooking / keep warm screen G1, a process adjustment display area A5 is formed, which allows you to adjust whether or not a process is on, and on the right side of the process adjustment display area A5, an "Off" button display B25 and a "Cook rice" button display B26 are arranged side by side. Here, the "Off" button display B25 includes a text display D25 that reads "Off," and the "Cook rice" button display B26 includes a text display D26 that reads "Cook rice."

[0053] At the top of the process adjustment display area A5 is a text display D21 reading "Process Selection," which reminds the user that the button displays B22 to B24 are operated to select whether or not a process is included, and below the "Process Selection" text display D21 are a button display B22 for moving the cursor left, a button display B24 for deciding the process, and a button display B23 for moving the cursor right, arranged side by side. Here, the button display B22 for moving the cursor left includes a left-pointing triangle mark D22, and similarly, the button display B24 for deciding the process includes a black circle mark D24, and the button display B23 for moving the cursor right includes a right-pointing triangle mark D23.

[0054] The cursor left button display B22, the step selection button display B24, and the cursor right button display B23 are operated when selecting whether or not to include a step in the rice cooking or keep-warm process, for example, when setting the rice cooking course of the rice cooker 100. Explaining in more detail, for example, when the rice setting, cooking method setting, and hardness setting are input, the display control means 53 controls the LCD 16 to display the rice cooking / keep-warm screen G. Here, when the step selection button display B24 is touched while the frame 71 is in the state shown in FIG. 6, the display control means 53 controls the LCD 16 to align the cursor C with one of the step displays D4 to D8 in the second step display area A2, for example, the last selected step, and to blink the cursor C, thereby informing the user that the user can select whether or not to include a step. In this state, when the button display B22 for moving the cursor left or the button display B23 for moving the cursor right is touched, the display control means 53 controls the LCD 16 to move the cursor C left or right and blink in accordance with the touched button display, for example, to move the cursor C to the "soaked" process display D5 and blink it.

[0055] Here, when the process selection button display B24 is touched, the display control means 53 controls the LCD 16 to turn off the process display where the cursor C is currently located if it is lit, or to turn on if it is off, for example, to turn off the process display D5 for "soaking" from a lit state. The display control means 53 also controls the LCD 16 to extract information about the currently displayed process from the rice cooking process information stored in the storage means 54, for example, information about the standby process, boiling and heating process, continued boiling process, steaming process, and keep warm process in this case, and calculates the expected end time of the rice cooking process when the current time is used as the start time, and displays this information on the cooking time display D14.

[0056] By configuring it in this way, the user can set the rice cooking process by selecting whether or not to include any steps, for example, by omitting the standby step, soaking step, or steaming step and manually soaking the rice or steaming the rice after the continuous boiling step in their own way, or by performing a rice cooking process in which the rice is promptly frozen after cooking without performing the keep warm step.This prevents the user from excessively overlapping the soaking step or steaming step already included in the rice cooking process, which could result in extra cooking time being spent or the taste of the cooked rice being reduced.

[0057] The "OFF" button display B25 is operated when stopping cooking rice or keeping it warm. When the "OFF" button display B25 is touched, the rice cooking control means 51 controls the cooking of the food in the pot 4 to stop heating or scheduled cooking and to turn it off, and the display control means 53 controls the LCD 16 to display the rice cooking / keeping it warm screen G1 with the settings from the most recent time rice was cooked, i.e., the settings stored in the memory means 48.

[0058] The "cooking rice" button display section B26 is operated when starting rice cooking or scheduled rice cooking, and when the "cooking rice" button display section B26 is touched, the rice cooking control means 51 stores the process settings currently displayed on the rice cooking / keep warm screen G1 in the memory means 54 as the settings for this rice cooking course, and controls the start of cooking for the food to be cooked in the main body 11 using the settings for this rice cooking course stored in the memory means 54.

[0059] Next, the operation of the rice cooker with the above configuration in the rice cooking process and the warming process will be described. Figure 9 shows the relationship between the pot temperature t, which is the temperature detected by the pot temperature sensor 12, and the output P of the heating coil 11 in the rice cooking process and the warming process of the rice cooker 100 of this embodiment. C and the output P of the pressure reducing pump 39 P The graphs show the changes over time in and . Also, Figure 9 shows the case where all the steps in the rice cooking process are performed without skipping any, and the process moves to the keep-warm step after the rice cooking process is completed.

[0060] 9, the operation of this embodiment during rice cooking will be described. First, rice as the food to be cooked and water as the liquid are placed in pot 4, and after placing this pot 4 in pot housing 3, lid 2 is closed. Around the same time, when the rice cooker is turned on, main body 1 and lid 2 enter the initial off (standby) state in which neither rice cooking nor keeping warm is taking place.

[0061] Then, using the remote control from the information terminal 62 or the operation means 19, rice settings such as the brand of rice, the precision of the rice pounding, the storage period after milling, the cooking method, the hardness, the water quality information, and other rice cooking course settings are set, and then the "cooking rice" button display B26 is touched to give the command to start cooking, and the rice cooking control means 51 will start the rice cooking process, which performs each of the cooking operations of the soaking cooking process, the boiling heating process, the continued boiling process, and the soaking process on the food to be cooked in the pot 4 in accordance with the heating pattern set for this rice cooking course.

[0062] When the rice cooking process starts, the process moves to the soaking process, and the rice cooking control means 51 controls the operation of the solenoid 35 and the vacuum pump 39 based on the pressure inside the pot 4 detected by the pressure sensor 36, so that the pressure inside the pot 4 is reduced below atmospheric pressure during the soaking process. Specifically, when the soaking process starts, the rice cooking control means 51 controls the solenoid 35 to close the steam exhaust path 33 with the pressure adjustment valve 34. Then, in this state, based on the pressure detected by the pressure sensor 36, the rice cooking control means 51 opens the path of the pressure reduction means 38 and continuously operates the vacuum pump 39, performing a vacuum by using the vacuum pump 39 to remove the air from inside the sealed pot 4. The display control means 53 also controls the LED display unit 17 to light up the "vacuum" process LED indicator, and controls the LCD 16 to display the rice cooking / keep warm screen G1 and move the cursor C to the "soaking" process indicator D5. After that, the rice cooking control means 51 controls the pressure reducing means 38 so that the pressure inside the pot 4 is maintained at a reduced pressure lower than atmospheric pressure and below a certain value. In this way, the inside of the pot 4 is kept in a reduced pressure state throughout the entire period of the soaking cooking process. The display control means 49 also controls the LCD 16 to blink the lamp indicator D2 for the heating process, and controls the LED display unit 17 to light up the LED indicator for the "vacuum" process.

[0063] Furthermore, when the soaking cooking process is started, rice cooking control means 51 performs a soaking and water absorption process in which it determines the time for the rice to absorb water based on the temperature detected at the bottom of pot 4 by pot temperature sensor 12. For example, in this embodiment, if polished rice is selected as the rice setting, rice cooking control means 51 determines that the soaking and water absorption process time T1 should be set to 120 minutes when the temperature detected by pot temperature sensor 12 is 5°C or lower, similarly determines that the soaking and water absorption process time T1 should be set to 90 minutes when the temperature detected by pot temperature sensor 12 is higher than 5°C but lower than 10°C, determines that the soaking and water absorption process time T1 should be set to 75 minutes when the temperature detected by pot temperature sensor 12 is higher than 10°C but lower than 20°C, and determines that the soaking and water absorption process time T1 should be set to 60 minutes when the temperature detected by pot temperature sensor 12 is higher than 20°C. In this embodiment, the time is set to the time it takes for the rice to absorb water until it is saturated, and the time for the rice to absorb water to the core is set according to the temperature of the water used for cooking rice, preventing the time for the rice to absorb water from becoming too short and preventing the rice cooking time from being unnecessarily long due to the soaking water absorption process. Furthermore, the rice cooking control means 51 controls the soaking process time T1 so that it is longer the lower the detected temperature of the bottom of the pot 4 at the start of the soaking process, ensuring that the rice absorbs water to the core in accordance with the water temperature. Note that these values ​​are merely examples, and the present invention is not limited to these.

[0064] In this embodiment, the rice cooking control means 51 changes the time T1 of the soaking and water absorption process depending on the selected hardness setting. For example, for settings from "normal" to "soft," the time T1 of the soaking and water absorption process is set to the time required for the rice to absorb water until saturated, as described above. This suppresses uneven gelatinization from the surface to the center of the rice grains, resulting in an overall sticky texture. On the other hand, for the hardest setting, the time T1 of the soaking and water absorption process is set to 0 minutes, omitting the soaking and water absorption process, resulting in the surface of the cooked rice grains being sticky due to gelatinization, while the interior of the rice grains has a chewy texture. For settings from "hard" to "normal," the time T1 of the soaking and water absorption process is set to 0 minutes to the time required for the rice to absorb water until saturated, depending on the setting. As the setting becomes "hard," the time T1 of the soaking and water absorption process decreases. This configuration allows rice to be cooked appropriately according to the user's preferences.

[0065] In this embodiment, the rice cooking control means 51 is configured to change the time T1 of the soaking and water absorption process depending on the type of rice (production area, variety, brand), rice milling level, storage period after milling, water hardness, etc. For example, when a production area, variety, brand rice with slow water absorption is set, when 50% polished rice with low milling level is set, or when rice stored one month after milling is set, the time T1 of the soaking and water absorption process is changed to 150% of the soaking time for normal polished rice. Also, when the hardness of the water in the pot 4 exceeds 80 mg / L, the time T1 is changed to 150% of the soaking time for normal polished rice, which is the soaking time for polished rice in soft water with a hardness of 30 to 50 mg / L, which is suitable for rice cooking. When brown rice is set, the time T1 of the soaking and water absorption process is changed to 300% of the soaking time for normal polished rice. By configuring it in this way, it is possible to set an appropriate soaking time T1 according to rice settings such as the rice brand, rice milling accuracy, and storage period after milling, as well as water quality information, and it is possible to cook rice appropriately according to the rice information.In addition, the required cooking time can be displayed more reliably, improving usability.

[0066] When the rice cooking control means 51 receives a timing signal from the timing means 45 indicating that the time T1 has elapsed since the soaking and water absorption process, it ends the soaking and water absorption process and moves to the enzyme activation process of the next soaking and cooking process. The rice cooking control means 51 outputs a heating control signal to the side coil driving means 46, and cooks the rice at a predetermined output for a predetermined time T i The side coil 11-1 is controlled so that the pot 4 is heated only for a time T i After the predetermined time T ii The side coil 11-1 is controlled to stop heating the pot 4 only at time T ii A capacity determination step is performed to determine the cooking capacity, which is the amount of rice to be cooked, based on the pot temperature t1 after a predetermined time T ii is the time when heating stops T i The time is set to a time that will allow a temperature drop that will enable capacity determination. In this embodiment, in the capacity determination process, bottom coil 11-2, which is the heating coil 11 closest to pot sensor 12, is not used, and only side coil 11-1, which is the heating coil 11 farthest from pot sensor 12, is used to heat pot 4. This prevents pot sensor 12 from being affected by the heating of heating coil 11, and prevents a deterioration in the accuracy of temperature detection by pot sensor 12.

[0067] In this embodiment, the time T i The time T is set to 30 seconds or more, and this "30 seconds" is the time required to distinguish between the minimum capacity, which is the minimum capacity judgment, and other capacities. ii This "1 minute" is the time required to determine the minimum capacity and other capacities. For example, in the "quick cooking" course, which prioritizes time in the rice cooking course, the time T i is 30 seconds, time T ii may be set to 1 minute.

[0068] In this embodiment, the time T iWhen the rice cooking control means 51 receives a detection signal from the pot sensor indicating that the pot temperature t has reached 60°C, the rice cooking control means 51 stops heating the pot 4 at the time of receiving the detection signal, and then continues heating for a predetermined time T ii The side coil 11-1 is controlled so that heating to the pot 4 is stopped only when the temperature of the rice and water to be cooked exceeds 60°C. If the rice and water to be cooked exceed 60°C, gelatinization of the rice will be promoted as the rice absorbs water, which may result in poorly cooked rice. Therefore, in the capacity determination process, the pot temperature t1 is set to be less than 60°C to prevent gelatinization of the rice as it absorbs water.

[0069] FIG. 10 is a graph showing the change in the temperature of the pot of a conventional rice cooker over time and the change in the temperature of the pot of the rice cooker of this embodiment over time for each amount of food being cooked during the capacity determination process of the soaking cooking process. 0O , t 0B , t 0M , t 0S is a graph of the temperature detected by the pot sensor 12 when the amount of rice to be cooked is extra large, large, medium, and small in a conventional rice cooker, and t shown by the dotted line 1O , t 1B , t 1M , t 1S 1 is a graph of the pot temperature t1, which is the temperature detected by the pot sensor 12 when the amount of rice to be cooked is extra large, large, medium, and small in the rice cooker of this embodiment. Conventionally, the pot 4 is heated using both the side coil 11-1 and the bottom coil 11-2, and t 0S In some cases, the temperature at the bottom of the pot 4 may rise too high, for example, reaching nearly 60°C, causing the rice to gelatinize. Therefore, in this embodiment, only the side coil 11-1 is used, and the output of the entire heating coil 11 is reduced compared to conventional rice cookers to heat the pot 4, thereby preventing the temperature at the bottom of the pot 4 from rising.

[0070] In this embodiment, the time T ii The rice cooking control means 51 determines the rice cooking volume based on the pot temperature t at the end of the time T ii The capacity determination based on the pot temperature t1 at the end of time T ii Even if it is only due to the pot temperature t1 at the end of time Tii Even if it is based on the difference between the pot temperature t1 at the end of the cooking process and the pot temperature at the start of the cooking process, ii The pot temperature at the end of the cooking time t1 and the time when heating stopped T i The pot temperature t at the start of the soaking process may be set to a predetermined fixed value.

[0071] In this embodiment, the time T ii The rice cooking capacity is determined only by the pot temperature t at the end of the cooking time. ii For the temperature of the pot at the end of the cooking time, a threshold range is set for each of the cases where the amount of rice to be cooked is extra large, large, medium, and small. ii The determination can be made based on the range in which the pan temperature falls at the end of the time T ii At the end of this embodiment, 1O , t 1B , t 1M , and t 1S The temperature difference between the 0O , t 0B , t 0M , and t 0S It can be seen that the temperature difference between the two is greater than the temperature difference between the two. In other words, the rice cooker of this embodiment can improve grouping accuracy and more accurately determine the rice cooking capacity by the amount of the larger temperature difference. Note that the present invention is not limited to this, and the method of determining the rice cooking capacity is one example.

[0072] The rice cooking control means 51 receives the time T iiWhen a timing signal indicating that the time has elapsed is received, the process moves to the soaking step of the soaking cooking process, and the rice cooking control means 51 outputs a heating control signal to the side coil driving means 46 and the bottom coil driving means 47 based on the temperature detected at the bottom of the pot 4 by the pot temperature sensor 12, controlling the side coil 11-1 and the bottom coil 11-2 to alternately energize, heating the pot 4, and as shown in Figure 9, is configured to raise and maintain the water temperature in the pot 4 to a predetermined temperature, for example, from 40°C to a maximum of 60°C, preferably 45°C to 55°C, thereby promoting the rice's absorption of water.

[0073] Specifically, the rice cooking control means 51 controls the rice cooking so that the side coil 11-1 and the bottom coil 11-2 are alternately energized with a duty ratio of A% for the bottom coil 11-2 and a duty ratio of B% for the side coil 11-1. Furthermore, throughout the entire rice cooking process, when there is a switchover between energizing the side coil 11-1 and energizing the bottom coil 11-2, the rice cooking control means 51 controls the rice cooking so that a switching time is inserted between the side coil 11-1 and the bottom coil 11-2, during which both the side coil 11-1 and the bottom coil 11-2 are turned off. The length of this switching time may be constant or may vary depending on the rice cooking process. Alternatively, the rice cooking control may not require a switching time. In this embodiment, the rice cooking control means 51 controls the side coil 11-1 and the bottom coil 11-2 with a constant current pattern during the soaking process regardless of the amount of food to be cooked determined in the capacity determination process, but it may also be controlled to change the duty ratio of the side coil 11-1 and the bottom coil 11-2 and change the current pattern depending on the amount of food to be cooked determined in the capacity determination process.

[0074] In this embodiment, the time T2 for the enzyme activation step is set to approximately 0 to 60 minutes, allowing the user to select the time required to bring out the sweetness of the rice being cooked according to preference. For example, if time T2 is set to 0 minutes, the enzyme activation step is skipped, and the rice cooking control means 51 transitions to the boiling heating step after completing the soaking and water absorption step. Therefore, setting time T2 to 0 minutes is similar to a conventional rice cooking method in which the soaking cooking step is manually skipped, suppressing the activity of the enzymes contained in the rice and resulting in cooked rice with a refreshing, crisp taste. On the other hand, if time T2 is set to a longer time, for example, 30 to 60 minutes, cooked rice will have a sticky, sweet taste. If time T2 is set to 15 to 30 minutes, cooked rice will have a taste with moderate stickiness and sweetness. Therefore, in this embodiment, the time T2 of the enzyme activation step can be extended to bring out the sweetness of the rice, or the time T2 can be shortened or omitted to reduce the stickiness and sweetness of the rice, making it possible to appropriately cook rice with different textures such as stickiness after cooking and different sweetness to suit your taste.

[0075] In this embodiment, the water temperature in pot 4 during the enzyme activation step is set according to the rice variety and brand of rice produced in that region, and the water temperature is set when the brand of rice is selected. This is because the characteristics of reducing sugar production vary depending on the rice variety, and the water temperature is set to maximize reducing sugar production capacity depending on the rice variety and brand of rice produced in that region. For example, for varieties such as Hinohikari, Hitomebore, Akitakomachi, and Koshihikari, or rice produced in northern Japan, the water temperature in pot 4 during the enzyme activation step is set to a high temperature of 50°C to 60°C. For varieties such as Kinuhikari and rice produced in southern Japan, the water temperature in pot 4 during the enzyme activation step is set to a low temperature of 30°C to 40°C. On the other hand, for varieties such as Hinohikari, Hitomebore, Akitakomachi, and Koshihikari, or rice produced in northern Japan, the water temperature in pot 4 during the enzyme activation step is set to a low temperature of 30°C to 40°C, thereby suppressing the production of reducing sugars as described above and enabling rice to be cooked with a refreshing taste.

[0076] Thereafter, when the rice cooking control means 51 receives a timing signal from the timing means 45 indicating that the time T1 of the soaking and water absorption process and the time T2 of the enzyme activation process have elapsed since the start of the simmering process, it ends the simmering cooking process and proceeds to the next boiling and heating process.

[0077] When proceeding to the boiling and heating process, the rice cooking control means 51 outputs heating control signals to the side coil driving means 46 and the bottom coil driving means 47 respectively, and controls to alternately energize the side coil 11-1 and the bottom coil 11-2 so as to heat the rice to be cooked in the pot 4 more strongly than in the simmering cooking process, and performs a heating process which is a process of heating until boiling of the rice to be cooked is detected.

[0078] Specifically, when proceeding to the heating process, the rice cooking control means 51 first slightly increases the duty ratio C% of the bottom coil 11-2 compared to the duty ratio A% in the simmering process (C > A) at the beginning of the heating process, and also makes the duty ratio of the side coil 11-1 and the duty ratio of the bottom coil 11-2 substantially the same, and controls in an energization pattern of alternately energizing the side coil 11-1 and the bottom coil 11-2 with an output slightly stronger than that in the simmering cooking process. Here, the rice cooking control means 51 changes the energization time of the side coil 11-1 and the bottom coil 11-2 according to the amount of the rice to be cooked determined in the capacity determination process in the boiling and heating process. For example, if the duty ratio of the bottom coil 11-2 is D% when the amount of the cooked rice is extremely large, E% when the amount of the cooked rice is large, F% when the amount of the cooked rice is medium, and G% when the amount of the cooked rice is small, the duty ratio is set to be larger in the order of D < E < F < G, and the duty ratio of the side coil 11-1 is set to D > E > F > G.

[0079] Furthermore, when the process moves to the boiling heating process, the rice cooking control means 51 controls the solenoid 35 to rotate the pressure regulating valve 34 to open the steam exhaust path 33, putting the inside of the pot 4 in communication with the outside of the main body 1, and releasing the steam from the food to the outside of the main body 1 from the steam outlet 15 via the steam exhaust path 33. The display control means 53 then controls the LED display unit 17 to turn off the "vacuum" process LED indicator, and controls the LCD 16 to move the cursor C from the "soaking" process indicator D5 to the "cooking" process indicator D6.

[0080] Thereafter, when the rice cooking control means 51 receives a timing signal from the timing means 45 indicating that a predetermined time has elapsed since the start of the boiling heating process, it energizes the bottom coil 11-2 for a period of J seconds and the side coil 11-1 for a period of K seconds in one cycle for a time that is the same as or different from the time that the bottom coil 11-2 was energized for a period of H seconds and the time that the side coil 11-1 was energized for a period of I seconds in one cycle at the beginning of the heating process, and controls for a predetermined time with an energization pattern that energizes the side coil 11-1 and the bottom coil 11-2 alternately at an output that is the same as or lower than the output at the beginning of the heating process, in the pattern of bottom coil 11-2 energized → switching time → side coil 11-1 energized → switching time, and controls the output P B and output P S In the subsequent boiling heating process, boiling continuation process, and steaming process, the rice cooking control means 51 controls the heating coil 11 with a current pattern that alternately energizes the side coil 11-1 and the bottom coil 11-2 in the following pattern: bottom coil 11-2 energized → switching time → side coil 11-1 energized → switching time. The current duration of the bottom coil 11-2 is set longer in the order of extra-large≦large≦medium≦small, while the current duration of the side coil 11-1 is set longer in the order of small≦medium≦large≦extra-large. The cycle of the current pattern, which is the pattern of current flow through the side coil 11-1 and the bottom coil 11-2 when the heating coil 11 is driven, is set longer in the order of small≦medium≦large≦extra-large. Note that the present invention is not limited to these, and the cycle and settings of the current pattern are merely examples.

[0081] Then, when the rice cooking control means 51 receives a timing signal from the timing means 45 indicating that a predetermined time has elapsed, the rice cooking control means 51 controls the current supply pattern to alternately energize the side coil 11-1 and the bottom coil 11-2, while maintaining a predetermined output (H+I≧J+K≧L+M), so that the total current supply time (L+M seconds) of the bottom coil 11-2 (L seconds) and the side coil 11-1 (M seconds) in one cycle is the same as or shorter than the total current supply time (J+K seconds) of the bottom coil 11-2 (J seconds) and the side coil 11-1 (K seconds) in the previous cycle. Here, the current supply time of the bottom coil 11-2 is set to be longer in the order of extra large≦large≦medium≦small, as before, while the current supply time of the side coil 11-1 is set to be longer in the order of small≦medium≦large≦extra large. As a result of heating the food to be cooked inside the pot 4 using the side coil 11-1 and bottom coil 11-2 in this manner, the pot temperature t detected by the pot sensor 12 gradually increases, and accordingly the lid temperature detected by the lid temperature sensor 32 gradually increases.

[0082] Thereafter, when the rice cooking control means 51 receives a temperature detection signal from the pot sensor 12 indicating that the pot temperature t has reached a predetermined temperature or higher, for example, 90°C or higher, and / or receives a temperature detection signal from the lid temperature sensor 32 indicating that the lid temperature has reached a predetermined temperature or higher, for example, 90°C or higher, it begins detecting boiling of the food to be cooked under pressure.

[0083] Specifically, the rice cooking control means 51 controls the solenoid 35 to roll the pressure regulating valve 34 to block the steam discharge path 33, thereby sealing the interior of the pot 4. Since the rice cooking object inside the pot 4 is strongly heated as described above, the interior of the pot 4 is pressurized until the rice cooking object reaches above atmospheric pressure, for example, 1.2 atmospheres, and the water in the rice cooking object can be boiled in this pressurized state. Thereby, by boiling the water in the rice cooking object at the optimal gelatinization temperature of rice at 105 ° C (in the case of 1.2 atmospheres) in the pressurized state, it is possible to ensure the balance between the hardness and stickiness of the rice. Further, the display control means 53 controls the LED display unit 17 so as to light the process LED display unit of "pressure". The rice cooking control means 51 may control the solenoid 35 to adjust the pressure inside the pot 4 based on the detected pressure of the pressure sensor 36, for example, by setting the type of rice.

[0084] Also, the rice cooking control means 51 makes the total energization time N + O seconds of the energization time N seconds of the bottom coil 11-2 and the energization time O seconds of the side coil 11-1 in one cycle substantially equal to the total energization time L + M seconds in one cycle of the previous heating process. On the other hand, the energization time N seconds of the bottom coil 11-2 is made slightly shorter than the energization time L seconds of the bottom coil 11-2 in the previous heating process (N <L), and the energization time O seconds of the side coil 11-1 is made slightly longer than the energization time M seconds of the side coil 11-1 in the previous heating process (O> M), and the energization pattern is controlled to alternately energize the side coil 11-1 and the bottom coil 11-2. Therefore, the rice cooking control means 51 controls the bottom coil 11-2 and the side coil 11-1 with different energization patterns until boiling and after detecting boiling in the heating process. On the other hand, similar to the heating process, the rice cooking control means 51 controls the bottom coil 11-2 and the side coil 11-1 with different energization patterns according to the amount of the rice cooking object.

[0085] The rice cooking control means 51 also calculates the slope of the detected temperatures, which indicates how much the temperatures detected by the pot sensor 12 and the lid temperature sensor 32 rise over a specified time period. Specifically, if the rice cooking control means 51 calculates that the rise in the pot temperature t (the temperature at the bottom of the pot 4) from the temperature detected by the pot sensor 12 has fallen below a specified rate of rise, such as 3°C or less in 120 seconds, it determines that boiling has been detected due to a change in the rate of rise of the pot temperature t. Alternatively, the rice cooking control means 51 may determine that boiling has been detected due to a change in the rate of rise of the lid temperature t2 if it calculates that the rise in the lid temperature (the temperature of the inner lid 24) from the temperature detected by the lid temperature sensor 32 has fallen below a specified rate of rise, such as 1°C or less in 60 seconds. When the rice cooking control means 51 detects boiling due to a change in the rate of rise of the pot temperature t, it proceeds to the next boiling continuation step. The rice cooking control means 51 may be configured to detect boiling due to a change in the rate of temperature rise of the pan temperature t and transition to the next boiling continuation step when it detects boiling due to a change in the rate of temperature rise of the lid temperature. Here, the predetermined temperature rise rates of the pan temperature t and the lid temperature used to detect boiling may be adjusted and set according to the amount of rice to be cooked determined in the capacity determination step. The method of boiling detection is one example, and the present invention is not limited to this.

[0086] In this embodiment, during the boiling heating process, which raises the temperature of the food to a boil in a short period of time, the rice cooking control means 51 controls the side coil 11-1 and the bottom coil 11-2 with three different current conduction patterns during the heating process until it detects boiling due to a change in the rate of temperature rise of the pan temperature t and / or boiling due to a change in the rate of temperature rise of the lid temperature. Even after detecting boiling, the rice cooking control means 51 continues to control the side coil 11-1 and the bottom coil 11-2 with a different current conduction pattern, switching the current conduction pattern of the heating coil 11 multiple times. This allows for precise adjustments to the appropriate current conduction pattern until the water in the food reaches a boil, reducing the risk of uneven cooking of the rice. However, the present invention is not limited to this. For example, the rice cooking control means 51 may switch the current conduction pattern of the heating coil 11 at least once during the boiling heating process until the water in the food reaches a boil, such as by detecting boiling and switching the current conduction pattern of the heating coil 11. In addition, the rice cooking control means 51 controls the bottom coil 11-2 and the side coil 11-1 with different current patterns depending on the amount of food being cooked, and by carefully changing the appropriate current pattern depending on the amount of food being cooked, the risk of uneven cooking of rice is reduced.

[0087] When the process moves to the continuing boiling process, the rice cooking control means 51 controls the heating coil 11 to be energized or deenergized until the pot temperature t reaches a predetermined temperature based on the temperature detection signal from the pot sensor 12, and also controls the lid heater 33 to be continuously energized so that the lid temperature t is maintained at a predetermined temperature, such as 98°C or higher, based on the temperature detected by the lid temperature sensor 32, thereby continuing to boil the food being cooked. During the continuing boiling process, the length of one cycle of the current flow pattern for the side coil 11-1 and bottom coil 11-2 when the heating coil 11 is driven is set to be longer than in the stable #1 process, i.e., the time during which the heating coil 11 is turned off.

[0088] Furthermore, once the process shifts to the boiling continuation process, the rice cooking control means 51 periodically controls the solenoid 35 to be energized and deenergized, and periodically opens and closes the steam exhaust path 33 with the pressure regulating valve 34, in order to repeatedly change the pressure inside the pot 4 between normal pressure and a pressure higher than atmospheric pressure.

[0089] When the rice cooking control means 51 calculates that the water inside the pot 4 starts to disappear during the boiling continuation process and the temperature at the bottom of the pot 4 has reached a predetermined temperature or higher from the temperature detected by the pot temperature sensor 15, or the temperature has risen at a predetermined rate of temperature rise, such as 0.5°C or more in 10 seconds, it begins to detect whether the rice being cooked is done.

[0090] When the rice cooking control means 51 starts detecting whether the rice is done, the rice cooking control means 51 controls the solenoid 35 to close the steam exhaust path 33 with the pressure regulating valve 34. The rice cooking control means 51 also increases the power supply time Q seconds to the bottom coil 11-2 per cycle compared to the power supply time O seconds to the bottom coil 11-2 per cycle in the stabilization #2 step (Q>O), while setting the power supply time R seconds to the side coil 11-1 per cycle to be less than the power supply time P seconds to the side coil 11-1 per cycle in the stabilization #2 step (R≦P), controlling the power supply pattern to alternately power the side coil 11-1 and bottom coil 11-2. Therefore, when detecting whether the rice is done, the power supply time Q seconds to the bottom coil 11-2 per cycle is set longer than the power supply time R seconds to the side coil 11-1. When detecting whether the rice is done, there is almost no water in the pot 4 and no internal or external convection occurs, so by energizing the bottom coil 11-2 for a longer time than the side coil 11-1, the water remaining in the bottom of the pot 4 can be heated more efficiently from the bottom side. Here, the energization time for the bottom coil 11-2 is set to be longer in the order of extra large ≧ large ≧ medium ≧ small, as before, and the energization time for the side coil 11-1 is also set to be longer in the order of extra large ≧ large ≧ medium ≧ small.

[0091] When the rice cooking control means 51 receives a temperature detection signal from the pot sensor 12 indicating that the pot temperature t has reached a predetermined dry-up temperature, for example 120°C, or calculates from the temperature detection signal from the pot sensor 12 that the pot temperature t has risen at a predetermined temperature rise rate or more, for example 0.5°C or more in 10 seconds, it determines that the water inside the pot 4 has run out and the rice to be cooked is ready, and proceeds to the next soaking process.

[0092] During the soaking process, the rice cooking control means 51 controls the lid heater 33 to continuously energize so that the lid temperature is maintained at a predetermined temperature based on the temperature detected by the lid temperature sensor 32, preventing condensation from forming on the inner lid 24 and maintaining a high temperature inside the pot 4 so that the rice does not burn. The heating coil 11 is continuously energized and deenergized for a predetermined period of time to control the temperature at the bottom of the pot 4. Even during this soaking process, the heating coil 11 is turned on and off to some extent, so the rice cooking control means 51 controls the power supply pattern in a manner similar to that used when detecting doneness, which has a short cycle time. The rice cooking control means 51 also controls the solenoid 35 to rotate the pressure regulator valve 34 to open the steam exhaust path 33, connecting the inside of the pot 4 to the outside of the main body 1, and releasing steam from the food to the outside of the main body 1 through the steam exhaust path 33 and the steam vent 15. The display control means 53 also controls the LED display unit 17 to turn off the "pressure" process LED display unit, and controls the LCD 16 to move the cursor C from the "cooking rice" process display unit D6 to the "steaming" process display unit D7.

[0093] Here, the rice cooking control means 51 controls the power on / off of the heating coil 11 by changing the heating amount and the steaming time T4 based on the information on the hardness setting of the rice cooking course. For example, when the hardness setting of the rice cooking course is "hard," the rice cooking control means 51 controls the power on / off of the heating coil 11 so that the heating amount is stronger than normal, and controls the steaming time T4 so that it is shorter than the normal steaming time. On the other hand, when the hardness setting of the rice cooking course is "soft," the rice cooking control means 51 controls the power on / off of the heating coil 11 so that the heating amount is weaker than normal, and controls the steaming time T4 so that it is longer than the normal steaming time.

[0094] In addition, when the rice cooking control means 51 receives a detection signal from the pot sensor indicating that the pot temperature t has dropped to the above-mentioned predetermined temperature, for example, 100°C, the rice cooking control means 51 controls the output P of the heating coil 11 for a short period of time. C After the short time has elapsed, the heating coil 11 is controlled to increase the output P CThis process is repeated twice to remove excess moisture from the cooked rice and improve its flavor.

[0095] Thereafter, when the rice cooking control means 51 receives a timing signal from the timing means 45 indicating that the soaking process time T4 has elapsed, the soaking process ends, the rice cooking process is completed, and the rice is transferred to the keep-warm process by the keep-warm control means 52.

[0096] In this embodiment, even after the rice cooking control means 51 detects boiling due to a change in the rate of temperature rise of the pan temperature t and / or boiling due to a change in the rate of temperature rise of the lid temperature, it switches the current conduction pattern of the heating coil 11 when it detects that the food is cooked, and also controls the current conduction pattern of the heating coil 11 to be switched during the soaking process, so that the water for the food continues to boil until the rice is cooked, and by carefully changing the current conduction pattern to an appropriate level even when the temperature is maintained high enough to prevent the rice from burning, the risk of uneven cooking of the rice is reduced. However, the present invention is not limited to this, and it is sufficient if the rice cooking control means 51 is configured to control the current conduction pattern to be switched at least once even after the water for the food has boiled, such as by switching the current conduction pattern during the soaking process.

[0097] The warming process of this embodiment is composed of three periods: a freshly cooked period, which is a predetermined period after the start of the warming process or a period during which the temperature of the rice is at or above a predetermined temperature, for example, 90°C or higher; a temperature-lowering period, which follows the freshly cooked period and is a predetermined period, for example, within 60 minutes after the start of the warming process, during which the temperature of the rice is gradually lowered; and a warming period, which is more than 60 minutes after the start of the warming process, during which the temperature of the rice is maintained at a warming temperature in the warming temperature range, for example, 70°C to 76°C, at which the Maillard reaction in the rice can be suppressed.

[0098] In this embodiment, in the keep-warm process, the keep-warm control means 52 outputs a heating control signal to the bottom coil drive means 47 to control the bottom coil 11-2 so as to heat the pot 4 at a predetermined output, and controls the current pattern in the keep-warm process so that the side coil 11-1 is not used. This suppresses the generation of mechanical noise caused by a mechanical switch such as a relay when switching between the side coil 11-1 and the bottom coil 11-2, thereby reducing noise during the keep-warm process.

[0099] When the process shifts to the keep-warm step, the keep-warm control means 52 calculates the temperature of the rice to be cooked based on the temperature detected by the pot sensor 12, and controls the temperature of the pot 4 by turning on and off the bottom coil 11-2 so that the temperature of the rice is maintained at a predetermined temperature, for example, 90°C or higher. The keep-warm control means 52 also controls the temperature of the inner lid 24 by turning on and off the lid heater 22 based on the temperature detected by the lid temperature sensor 32 so that the temperature of the inner lid 24's surface facing the pot 4 is higher on average than the temperature of the rice in the pot 4. This prevents condensation on the inner lid 24's surface facing the pot 4 and prevents the sauce from dripping onto the rice, maintaining the rice in a freshly cooked state and tasting like freshly cooked rice. The display control means 53 then controls the LED display 17 to light the "keep-warm" process LED indicator and the LCD 16 to move the cursor C from the "steaming" process indicator D7 to the "keep-warm" process indicator D8. When the keep-warm control means 52 receives a timing signal from the timing means 45 indicating that a predetermined time, such as 30 minutes, has elapsed since the start of the fresh cooking period, the temperature-lowering period begins.

[0100] During the temperature-reducing period, heat retention control means 52 controls bottom coil 11-2 based on temperature t1 detected by pot sensor 12 to control the temperature of pot 4, and reduces the temperature of the rice in pot 4 to a heat retention temperature of, for example, 70°C to 76°C within the heat retention temperature range over a predetermined period of time, such as 60 minutes, after the start of the heat retention process. At the same time, heat retention control means 52 controls lid heater 31 based on the temperature detected by lid temperature sensor 32 to control the temperature of inner lid 24 and prevent condensation from forming on inner lid 24. During the temperature-reducing period, heat retention control means 52 may control solenoid 35 to close steam exhaust path 33 with pressure regulator valve 34. After degassing in the steaming step of the rice cooking process, communication between the inside and outside of pot 4 is blocked, and the temperature of rice (the food to be cooked) is reduced from near the boiling temperature to a heat retention temperature within the heat retention temperature range. This reduces the temperature of gases such as steam in pot 4, turning them into liquids such as water, and placing the inside of pot 4 in a reduced-pressure, degassed state. When the heat retention control means 52 determines that a predetermined time has elapsed since the start of the heat retention process and that the temperature of the rice inside the pot 4 has dropped to the heat retention temperature based on the temperature detected by the pot sensor 12, it moves on to the next heat retention period.

[0101] During the keep-warm period, the heat-retention control means 52 controls the temperature of the pot 4 by turning the bottom coil 11-2 on and off based on the temperature t detected by the pot sensor 12 to maintain the temperature of the rice within the keep-warm temperature range, for example, 70°C to 76°C. This prevents the rice in the pot 4 from yellowing or emitting a distinctive odor, which would otherwise cause the rice to deteriorate. At the same time, the heat-retention control means 52 controls the lid heater 31 based on the temperature detected by the lid temperature sensor 32 to control the temperature of the inner lid 24 and prevent condensation from forming on the inner lid 24. During the keep-warm period, the heat-retention control means 52 may also control the solenoid 35 to close the steam exhaust path 33 with the pressure regulator valve 34, thereby blocking communication between the inside and outside of the pot 4 and preventing the entry of putrefactive bacteria and food poisoning bacteria through the steam vent 17a and cold air from the outside. If the inside of the pot 4 is in a vacuum-deaerated state during the temperature-reducing period, this vacuum-deaerated state can be maintained.

[0102] As described above, the rice cooker 100 of this embodiment is equipped with rice cooking control means 51 as control means for controlling the rice cooking process that cooks rice and water as the food to be cooked, and display means 18 and operation means 19 that can select and operate the rice information displayed on display means 18 as selection means for selecting rice information such as the rice brand, rice pounding precision, and storage period after milling.The rice cooking process includes a soaking process to promote water absorption by the rice, and the soaking process includes a soaking process in which the rice is soaked in unheated water and an enzyme activation process in which the temperature of the food to be cooked is raised, for example, from 40°C to a maximum of 60°C, preferably 45°C to 55°C, and the rice is soaked in heated water at the enzyme activation temperature.The rice cooking control means 51 is configured to control the soaking process time T1 according to the selected rice information setting.

[0103] By configuring it in this way, it is possible to cook rice appropriately depending on rice information such as the brand of rice, the precision of pounding the rice, and the storage period after milling the rice.

[0104] Furthermore, rice cooker 100 of this embodiment is equipped with pot temperature sensor 12 as temperature detection means for detecting the temperature of pot 4 containing the food to be cooked, and rice cooking control means 51 is configured to control the soaking step time T1 according to the temperature of pot 4, which is based on the temperature of the water at the start of the rice cooking step. This makes it possible to set the time for the rice to absorb water all the way to the core according to the temperature of the water used for cooking rice, preventing the time for rice absorption from becoming too short and also preventing the rice cooking time from being unnecessarily long due to the soaking and water absorption step being unnecessarily long.

[0105] Furthermore, in the rice cooker 100 of this embodiment, the rice cooking control means 51 is configured to control the soaking process time T1 so that the lower the temperature of the pot 4 at the start of the rice cooking process, the longer the soaking process time T1, ensuring that the rice absorbs water to the core in accordance with the temperature of the water used for cooking the rice.

[0106] In addition, in the rice cooker 100 of this embodiment, the rice cooking control means 51 is configured to control the temperature of the food being cooked during the enzyme activation process so that it is raised to the enzyme activation temperature according to the rice information, and it is possible to set the water temperature to maximize the reducing sugar production ability according to the rice information, and it is also possible to appropriately cook rice with different textures such as stickiness after cooking and different sweetness.

[0107] 11 and 12 show a rice cooker 100' that is a modified example of the first embodiment. This modified example is configured to include cooling means 81 that cools the food to be cooked.

[0108] FIG. 11 shows the electrical configuration of the rice cooker 100' in this modified example. In the figure, 81 denotes a cooling means for cooling the water and rice in the pot 4. The cooling means 81 may be configured to cool the food, particularly the water, in the pot 4. For example, as in the cooling device or cold storage device disclosed in Japanese Patent Application Laid-Open No. 10-14758, a heat exchange plate with good thermal conductivity may be attached to the outside of the inner frame 5 while forming a space or gap, and the heat exchange plate may be cooled by a thermoelectric element to cool the food along with the pot 4. Alternatively, as disclosed in Japanese Patent Application Laid-Open No. 2020-74941, a Peltier unit may be provided on the lid 2 side to cool the food in the pot 4. Furthermore, ice or other cooling materials may be added to the pot 4 during the immersion water absorption process.

[0109] FIG. 12 shows the relationship between the pot temperature t', which is the temperature detected by the pot temperature sensor 12, and the output P' of the heating coil 11 during the rice cooking process and the keep-warm process of the rice cooker 100' of this modified example. C and the output P of the cooling means 81 R and the output P' of the decompression pump 39 PThe graphs show the changes over time in the above and the above. Referring to the same figure, the operation of this embodiment during rice cooking will be described. After setting rice settings such as the brand of rice, the degree of pounding, and the storage period after milling, as well as the cooking method, hardness, and water quality information, etc., via remote control from information terminal 62 or via operation means 19, when the "cook rice" button display B26 is touched to start cooking, rice cooking control means 51 starts the rice cooking process, which involves performing the soaking cooking process, boiling heating process, continued boiling process, and steaming process on the food in pot 4 according to the heating pattern set for the current rice cooking course.

[0110] When the rice cooking process is started, the process moves to the soaking cooking process, and the rice cooking control means 51 drives the cooling means 81 to perform the soaking water absorption process in which the rice is made to absorb water in cold water of a predetermined temperature.

[0111] Regarding the rate at which rice absorbs water, when the water temperature is 20°C or higher, rice initially absorbs water faster than when the water temperature is 10°C or lower. However, after about 60 minutes, the rate of water absorption slows down, and when the water temperature is 10°C or lower, the rate of water absorption is higher than when the water temperature is 20°C or higher. This is thought to be because when the water temperature is 20°C or higher, the starch granules on the surface of the rice grain swell after about 60 minutes, closing the gaps between the grains and inhibiting further water absorption. Therefore, by cooling and maintaining the water temperature in pot 4 at 20°C or lower, preferably 15°C or lower, the rate of water absorption when the rice in pot 4 reaches saturation is increased, eliminating uneven water absorption from the center to the surface of the rice grain.

[0112] Specifically, when the process moves to the immersion absorption process, the rice cooking control means 51 controls the cooling means 81 to operate based on the temperature of the bottom of the pot 4 detected by the pot temperature sensor 12, thereby cooling the food to be cooked and lowering the water temperature in the pot 4 to a predetermined temperature, for example, 0°C to 20°C or less, preferably 0°C to 15°C or less, and maintaining that temperature, as shown in Figure 12. Therefore, the immersion absorption process in this modified example functions as a cooling absorption process.

[0113] As in the first embodiment, the rice cooking control means 51 controls the solenoid 35 to close the steam exhaust path 33 with the pressure regulator valve 34. In this state, the rice cooking control means 51 opens the path of the pressure reduction means 38 based on pressure detection by the pressure sensor 36, and continuously operates the vacuum pump 39 to remove air from the sealed pot 4. The display control means 53 also controls the LED display 17 to light the "vacuum" process LED indicator and controls the LCD 16 to display the rice cooking / keep-warm screen G1 and move the cursor C to the "soaking" process indicator D5. The rice cooking control means 51 then controls the pressure reduction means 38 to maintain the pressure inside the pot 4 at a reduced pressure lower than atmospheric pressure, for example, at a constant value of approximately 0.3 atm to 0.7 atm. In this way, the inside of the pot 4 is maintained at a reduced pressure throughout the entire soaking process. The display control means 49 also controls the LCD 16 so that the lamp indicator D2 for the heating step flashes, and also controls the LED display unit 17 so that the LED indicator for the "vacuum" step lights up.

[0114] In this modified example, the time T1 for the soaking and water absorption step is set based on the set temperature of the water in pot 4 that is kept cooled and the set pressure in pot 4 that is kept reduced pressure. For example, when pot 4 is at atmospheric pressure and the water temperature in pot 4 is between 0°C and 20°C, the time T1 for the soaking and water absorption step is set to 90 to 120 minutes. Furthermore, when pot 4 is kept at reduced pressure, the air layer in pot 4 is depressurized and degassed, degassing the water in the rice being cooked. This removes dissolved gases, increasing the purity of the water and improving the rice's water absorption efficiency. Furthermore, reduced pressure reduces the air pressure acting on the water surface in pot 4, lowering the boiling point of the water. However, water molecules below the boiling point become more active, which increases the movement of the water in pot 4 and improves water absorption. Therefore, when pot 4 is kept at approximately 0.3 atm to 0.7 atm and the water temperature in pot 4 is between 0°C and 20°C, the time T1 for the soaking and water absorption step is reduced by half, for example, to 45 to 60 minutes. Note that this is just one example, and the higher the degree of pressure reduction, the greater the effect of promoting water absorption by rice, so these values ​​may be set according to the characteristics of the rice cooker.

[0115] When the rice cooking control means 51 receives a timing signal from the timing means 45 indicating that time T1 has elapsed since the soaking and water absorption step, it ends the soaking and water absorption step and moves on to the next enzyme activation step. In this way, in this modified example, after the rice is allowed to absorb water all the way to its core in cold water at 0°C to 20°C or less, the enzyme activity of the rice is promoted in the enzyme activation step, so gelatinization is promoted evenly all the way to the center of the rice grain and the sweetness of the rice is maximized to produce delicious cooked rice.

[0116] As described above, the rice cooker 100' of this modified example is configured with a cooling means 81 for cooling the food being cooked, which allows for uniform gelatinization to be promoted all the way to the center of the rice grains, and also allows for delicious cooked rice that brings out the maximum sweetness of the rice. [Example]

[0117] 13 to 15 show a second embodiment of a rice cooker 100" according to the present invention. This embodiment is provided with water level detection means 91 capable of detecting the water level in the pot 4, and the rice cooking control means 51 is configured to perform control in accordance with changes in the water level in the pot 4 detected by the water level detection means 91.

[0118] Figures 13(A) to (J) show observations of the changes over time in the water level and rice height in pot 4, starting from the point when two cups of polished Koshihikari rice produced in Minami Ward, Niigata City was washed in tap water from Minami Ward, Niigata City at approximately 15°C and the water level in pot 4 was adjusted to match the two-cup water level line using that tap water. Table 1 also tabulates the results of Figures 13(A) to (J). [Table 1] It can be seen from Figure 13 and Table 1 that the water level and rice height rise for the first 30 minutes after the rice has been soaked in water, but do not change significantly after 45 minutes. This shows that it takes approximately 30 minutes from the time the water level and rice height in pot 4 become approximately stable after 30 minutes have passed since the start of soaking, when the water level and rice height become approximately stable, until the water absorption rate of the rice becomes approximately stable.

[0119] Table 2 shows the relationship between the temperature of the water in pot 4 and the time it takes for the water level and rice height in pot 4 to stabilize, as well as the time it takes for the rice's water absorption to stabilize. Here, the item "(C) Time it takes for the water absorption to stabilize" refers to "The effect of hot water soaking and cold water soaking on the water absorption rate of rice during rice cooking" (Journal of the Japanese Society of Cookery Science, vol. 48(3), 193-199, 2015). Also, the "*" in (A) Time it takes for the rice height or water level in the pot to stabilize is an assumed value, as will be described later. [Table 2] If the water used to cook rice in pot 4 is cold water at 10°C or below, it takes 120 minutes for the rice's water absorption to stabilize, so if it takes 30 minutes for the water level and rice height to stabilize, it will take 90 minutes from when the water level and rice height stabilize to when the rice's water absorption stabilizes. On the other hand, if the water is cold water at 10°C or below, as mentioned above, it will take longer for the water level and rice height to stabilize, so it is expected that it will take less than 90 minutes for the rice's water absorption to stabilize from when the water level and rice height stabilize. Similarly, if the water used to cook rice in pot 4 is warm water at 30°C or above, it will take 60 minutes for the rice's water absorption to stabilize, so if it takes 30 minutes for the water level and rice height to stabilize, it will take 90 minutes from when the water level and rice height stabilize to when the rice's water absorption stabilizes. On the other hand, if the water is warm (30°C or higher), as mentioned above, the water absorption rate is faster and the time it takes for the water level and rice height to stabilize is shorter. Therefore, it is expected that it will take less than 30 minutes for the rice's water absorption rate to stabilize after the water level and rice height have stabilized. Therefore, from Table 2, the following relationships can be derived: (B) = 2 × (A) and (C) = (A) + (B), or (C) = 3 × (A) and (B) = (C) - (A). By determining the time for (A), it is possible to determine (C), the soaking time required to reach near saturation, and the value (B), which is derived from (A) and (C). Therefore, by considering the appropriateness of the time for (A) in relation to the water temperature in pot 4, the accuracy of the rice cooking time can be further improved.

[0120] FIG. 14 shows the electrical configuration of rice cooker 100" in this modified example. In the same figure, 91 is water level detection means composed of, for example, an ultrasonic sensor, which detects the height of the rice to be cooked and the water level in pot 4. Water level detection means 91 can be configured to detect the height of the rice and water level in pot 4, and one example is the water level sensor configuration disclosed in Japanese Patent Application Laid-Open No. 05-261018. A CCB image sensor may also be used as water level detection means 91, and one example is the water level sensor, rice level sensor, or rice / water level sensor configuration disclosed in Japanese Patent Application Laid-Open No. 2012-152635.

[0121] Next, the operation of the rice cooker configured as described above in the rice cooking process and the rice keeping process will be described with reference to Figures 9 and 15. Figure 15 shows the time it takes for the temperature of the water in the pot 4 and the water level and rice height in the pot 4 to stabilize, the predetermined temperature in the enzyme activation process, and the output P of the heating coil 11 in the rice cooking process. C , the time T4 of the soaking process, and the temperature for keeping warm in the keeping warm process. In the rice cooker 100" of this embodiment, the setting of the time T1 of the soaking and water absorption process according to the temperature of the water in the pot 4 at the start of cooking, the setting of the temperature of the enzyme activation process according to the time for the water temperature in the pot 4 and the water level and rice height in the pot 4 to stabilize, the setting of the output of the heating coil 11 in the rice cooking process, the setting of the time T4 of the soaking process, and the setting of the temperature for keeping warm in the keeping warm process are stored in memory means 48, and these settings are changed by detecting the temperature of the water at the start of cooking and detecting the time for the water level and rice height to stabilize.

[0122] When the rice cooking process starts, the process moves to the soaking cooking process, and the rice cooking control means 51, as in the first embodiment, reduces the pressure inside the pot 4 to a reduced pressure lower than atmospheric pressure and performs a soaking water absorption process that determines the time for the rice to absorb water based on the temperature detected at the bottom of the pot 4 by the pot temperature sensor 12. Here, the rice cooking control means 51 stores the temperature at the bottom of the pot 4 at the start of the rice cooking process, i.e., the temperature of the water to be cooked, in the memory means 44. The rice cooking control means 51 then detects the height of the rice and the water level in the pot 4 at predetermined intervals, such as every minute, using the water level detection means 91 and stores the results in the memory means 44.

[0123] In this embodiment, the time T1 for the soaking and water absorption step is first set according to the temperature of the water in the pot 4 at the start of rice cooking. As shown in Table 2, the rice cooking control means 51 sets the time T1 for the soaking and water absorption step to 120 minutes if the water temperature is 10°C or lower according to the water temperature at the start of rice cooking stored in the memory means 44, and sets the time T1 for the soaking and water absorption step to 90 minutes if the water temperature is above 10°C but not higher than 20°C.

[0124] In the soaking water absorption step, the rice in pot 4 absorbs water, causing the rice height and water level in pot 4 to rise. When the rice cooking control means 51 determines, as detected by the water level detection means 91, that the change in the rice height or water level in pot 4 has reached a predetermined rate of change, for example, 0.5 mm or less per 5 minutes, it determines that the rice height or water level in pot 4 has stabilized, and calculates (A) the time at which the rice height or water level in the pot stabilizes, which is the time from the start of the rice cooking step to the determination, using the timing means 45. It then applies the water temperature at the start of rice cooking stored in the memory means 44 and the time (A) calculated this time to the tables of Figures 15(A) and (B) to calculate the predetermined temperature for the enzyme activation step, the output P of the heating coil 11 in the rice cooking step, C The time T4 for the soaking step and the temperature for the heat retention step are reset, and the time T1 for the soaking and water absorption step is reset based on the above-mentioned relational expression.

[0125] Specifically, when the rice is set to "fast" with a high water absorption rate, the predetermined temperature in the enzyme activation process is lowered compared to the "normal" setting, which is the normal setting in the current rice cooking course, and the output P of the heating coil 11 in the rice cooking process is C On the other hand, when the rice is set to "slow" mode, which means that the rice has a slow water absorption rate, the specified temperature in the enzyme activation step is increased compared to the "normal" mode, which is the normal setting for the current rice cooking course, and the output P of the heating coil 11 in the rice cooking step is lowered. C The time T4 of the soaking step is increased and the temperature of the warming step is increased.

[0126] For example, as shown in FIG. 13, if the water temperature at the start of rice cooking is 15°C, and (A) the time when the height of the rice and the water level in the pot 4 have stabilized is 30 minutes after the start of the rice cooking process, the rice cooking control means 51 derives "Fast (2)" from the table in FIG. 15(A), applies this "Fast (2)" to the table in FIG. 15(B), and, compared with "Normal", which is the normal setting for the current rice cooking course, lowers the temperature for the enzyme activation process from the normal setting of 45°C to 55°C and resets it to 35°C to 45°C, and reduces the output P of the heating coil 11 in the rice cooking process. C is reset to bW, increasing the temperature of the soaking step from the normal setting of dW, the time T4 of the soaking step is reset to i minutes, decreasing the time T4 of the soaking step from the normal setting of k minutes, and the keep-warm control means 52 resets the keep-warm temperature of the keep-warm step to q°C, decreasing the temperature of the keep-warm step from the normal setting of s°C. Furthermore, the rice cooking control means 51 applies the fact that the time of (A) is 30 minutes to the aforementioned relational equations (C) = 3 × (A) and (B) = (C) - (A), and resets the time T1 of the soaking and water absorption step to 30 minutes × 3 = 90 minutes. Note that the numerical values ​​in Figure 15 are merely examples, and the present invention is not limited to these.

[0127] Thereafter, when the rice cooking control means 51 receives a timing signal from the timing means 45 indicating that 60 minutes, which is the time (B) obtained by subtracting the time (A) from the time T1 of the soaking and water absorption process of 90 minutes, has elapsed since the time (A), the rice cooking control means 51 ends the soaking and water absorption process and moves on to the next enzyme activation process.

[0128] As described above, in this embodiment, the water level detection means 91 is provided which can detect the water level, which is the height of the water in the pot 4, and the height of the rice, and the rice cooking control means 51 and the rice keep-warm control means 52 are configured to perform control in response to changes in the water level and the height of the rice detected by the water level detection means 91. For example, after rice settings such as the brand of rice, the pounding accuracy, and the storage period after polishing, as well as settings for the cooking method, the hardness, and the water quality information are set and rice cooking courses are started, the water level detection means 91 is used to calculate (A) the time for the rice height or water level in the pot to stabilize, and to determine the water absorption rate of the rice when the rice is immersed in water in the pot 4 and (C) the time for the water absorption rate to stabilize, which is the time until saturated water absorption, and to set a predetermined temperature for the enzyme activation step, the output P of the heating coil 11 in the rice cooking step, CThe time T4 for the soaking process, the temperature for the keep-warm process, and the time T1 for the soaking and absorbing process are reset. This allows the time T1 for the soaking and absorbing process to be adjusted so that the rice in the pot 4 absorbs sufficient water, further improving the accuracy of the rice cooking time. Even if the user sets the wrong rice cooking course, for example, the rice can be cooked with the optimal setting according to the water absorption characteristics of the rice to be cooked. Furthermore, since the rice cooking course is reset based on detection by the water level detection means 91 after the rice cooking process has been set and the rice cooking process has begun, even if the water level detection means 91 detects incorrectly, the heating pattern of the heating coil 11 is not significantly affected because there is a basic rice cooking course setting, and the risk of the rice being cooked extremely poorly can be reduced.

[0129] As described above, the rice cooker 100" of this embodiment is configured to include water level detection means 91 that can detect the water level in the pot 4, and the time T1 of the soaking and water absorption process can be adjusted so that the rice in the pot 4 absorbs enough water, further improving the accuracy of the rice cooking time.

[0130] Furthermore, in the rice cooker 100" of this embodiment, the rice cooking control means 51 is configured to perform control in response to changes in the water level detected by the water level detection means 91, and rice can be cooked at the optimum setting according to the water absorption characteristics of the rice to be cooked.

[0131] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention. For example, the first and second embodiments and their modifications may be combined. Alternatively, the amount of food to be cooked may be displayed selectably on the display means 18, and the cooking course may be selected and set by selecting and setting the setting using the operation means 19. The amount of food to be cooked may also be confirmed in the capacity determination process. The numerical values ​​exemplified in the embodiments are merely examples, and may be modified as appropriate depending on the specifications of the rice cooker. [Explanation of symbols]

[0132] 4. Hotpot 12 Pot sensor (temperature detection means) 18 Display means (selection means) 19 Operating means 51 Rice cooking control means (control means) 81 Cooling means 91 Water level detection means 100,100',100" rice cooker T1 Dipping time

Claims

1. A control means for controlling a rice cooking process for cooking rice and water as food to be cooked; a selection means for selecting the information on the rice; The rice cooking process includes a soaking process for promoting water absorption of the rice, and the soaking process includes a soaking process for soaking the rice in the unheated water, and an enzyme activation process for raising the temperature of the food to be cooked and soaking the rice in the heated water after the soaking process. The control means controls the soaking time in accordance with the selected information about the rice.

2. A temperature detection means for detecting the temperature of the pot containing the food to be cooked is provided, 2. The rice cooker according to claim 1, wherein the control means controls the time of the soaking step in accordance with the temperature of the pot, which is based on the temperature of the water at the start of the rice cooking step.

3. 3. The rice cooker according to claim 2, wherein the control means controls the soaking step so that the lower the temperature of the pot at the start of the rice cooking step, the longer the time of the soaking step.

4. 3. The rice cooker according to claim 2, wherein the control means controls the temperature of the food to be cooked in the enzyme activation step so as to raise the temperature to an enzyme activation temperature corresponding to the rice information.

5. 3. The rice cooker according to claim 2, further comprising a water level detection means capable of detecting the water level in the pot.

6. 6. The rice cooker according to claim 5, wherein the control means performs control in response to a change in the water level detected by the water level detection means.

7. 7. The rice cooker according to claim 1, further comprising a cooling means for cooling the food to be cooked.

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