CN109124331B

CN109124331B - Rice cooker

Info

Publication number: CN109124331B
Application number: CN201810635060.9A
Authority: CN
Inventors: 中须慧; 塚原知里; 大矢弘; 山地宏和; 冈本大辅
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2017-06-28
Filing date: 2018-06-20
Publication date: 2021-09-14
Anticipated expiration: 2038-06-20
Also published as: CN109124331A

Abstract

Provided is a rice cooker that can control the rice cooking operation with high precision and enhance the taste of the food to be cooked. A rice cooker (1) has: a pot (5) that accommodates objects to be cooked; a heating unit (11) that heats the pot (5); and a pressure adjusting unit (13) that has a A pressure valve (4a) for releasing gas in ), the pressure adjustment part (13) adjusts the pressure in the pot (5) by adjusting the opening and closing state of the pressure valve (4a); the pressure detection part (22), It detects the pressure in the pot (13); and a control part (20) controls the heating part (11) and the pressure adjustment part (22) to execute the cooking process. The control unit (20) changes the control unit (20) to the heating unit (11) and the pressure adjustment unit (13) between a first state and a second state in which the modes of the pressure change in the pot (5) are different from each other. ) is controlled by at least one of the parties.

Description

Rice cooker

Technical Field

The disclosure herein relates to a rice cooker.

Background

Conventionally, there are known pressure rice cookers as follows: the rice cooker is sealed and cooked while being heated under a predetermined pressure. In a pressure cooker, contents (i.e., an object to be cooked and water) are heated in a sealed rice cooker. Therefore, the temperature in the rice cooker rises when the rice cooking is started, and the pressure in the rice cooker increases due to the evaporation of the moisture of the contents. When the pressure in the rice cooker reaches a set value, the control unit of the pressure rice cooker controls the heating power of a heating unit (heater) that heats the rice cooker, and heats the contents while maintaining the pressure in the rice cooker at the set value (see, for example, patent document 1).

In the rice cooker disclosed in patent document 1, when the pressure in the rice cooker is lower than a set value when a certain time has elapsed after the start of cooking, the heating power of the heater is changed to output the second heating power higher than the first heating power.

Patent document 1: japanese patent laid-open publication No. 2005-211577

However, in the conventional rice cooker, since only the detection of whether or not the pressure in the rice cooker has reached a predetermined value after a lapse of a certain time from the time of cooking is performed, it is difficult to grasp the cooking state of the object to be cooked.

Disclosure of Invention

Accordingly, an object of the present disclosure is to provide a rice cooker capable of grasping a cooking state of an object to be cooked, controlling a cooking operation with high accuracy, and improving a taste of the object to be cooked.

One embodiment of the rice cooker disclosed herein includes: a pot for accommodating the material to be cooked; a heating unit that heats the pan; a pressure adjustment unit having a pressure valve for releasing gas from the cooker, the pressure adjustment unit adjusting the pressure in the cooker by adjusting the open/close state of the pressure valve; a pressure detecting unit that detects the pressure in the pan; and a control unit for controlling the heating unit and the pressure adjustment unit to perform a cooking process. The control unit changes control of at least one of the heating unit and the pressure adjustment unit between a1 st state and a 2 nd state in which pressure changes are different from each other. The manner in which the pressure varies corresponds to the gradient of the pressure variation curve in the case where the relationship between time and the pressure in the pan is expressed as the pressure variation curve. The rice cooker further has: a time measuring unit for measuring the time; and a storage unit that stores, as the pressure change curve, a relationship between the time measured by the time measuring unit and the pressure detected by the pressure detecting unit. When a relation between time and pressure in the pot in a case where a water addition ratio of the material to be cooked is a predetermined water addition ratio is represented as a reference curve, the 1 st state is a state in which the gradient of the pressure change curve is steeper than that of the reference curve, and the 2 nd state is a state in which the gradient of the pressure change curve is gentler than that of the reference curve. The storage unit stores the reference curve, and the control unit compares the gradient of the pressure change curve with the gradient of the reference curve. The control unit detects a difference between a water addition ratio corresponding to the pressure change curve and the predetermined water addition ratio corresponding to the reference curve, calculates a correction value corresponding to the difference, and changes the control of at least one of the heating unit and the pressure adjusting unit using the correction value.

The rice cooker disclosed herein can control a cooking operation with high accuracy, thereby improving the taste of an object to be cooked.

Drawings

Fig. 1A is an external perspective view of the rice cooker of embodiment 1.

Fig. 1B is an exploded perspective view of the rice cooker of embodiment 1.

Fig. 2 is a block diagram showing the structure of the rice cooker of embodiment 1.

Fig. 3A is a diagram showing the pressurization gradient of the rice cooker of embodiment 1.

Fig. 3B is a diagram showing the decompression gradient of the rice cooker of embodiment 1.

Fig. 4 is a flowchart illustrating a cooking process of the rice cooker of embodiment 1.

Fig. 5A is a flowchart illustrating a boiling process of the rice cooker of embodiment 1.

Fig. 5B is a time chart showing a pressure change and a temperature change in the boiling process of the rice cooker according to embodiment 1, in which (a) shows a pressure change and (B) shows a temperature change.

Fig. 6 is a flowchart illustrating the 1 st pressurization process of the rice cooker of embodiment 1.

Fig. 7 is a flowchart illustrating the 1 st depressurization process of the rice cooker of embodiment 1.

Fig. 8 is a flowchart showing the 2 nd pressurizing and depressurizing step of the rice cooker of embodiment 1.

Fig. 9 is a flowchart showing the 3 rd pressurizing and depressurizing step of the rice cooker according to embodiment 1.

Fig. 10 is a flowchart showing the 4 th pressurizing and depressurizing step of the rice cooker according to embodiment 1.

Fig. 11 is a flowchart illustrating a dry up (dry up) process of the rice cooker according to embodiment 1.

Fig. 12 is a flowchart showing a high temperature maintaining process of the rice cooker according to embodiment 1.

Fig. 13 is a flowchart showing a steaming process of the rice cooker of embodiment 1.

Fig. 14 is a timing chart showing pressure changes in the boiling process of the rice cooker of embodiment 1.

Fig. 15 is a timing chart showing pressure changes in the boiling process of the rice cooker of example 2.

Fig. 16 is a timing chart showing pressure changes in the boiling process of the rice cooker of example 3.

Fig. 17 is a timing chart showing pressure changes in the boiling process of the rice cooker of example 4.

Fig. 18 is a timing chart showing pressure changes in the boiling process of the rice cooker of example 5.

Fig. 19 is a timing chart showing pressure changes in the boiling process of the rice cooker of example 6.

Fig. 20 is a diagram showing a water adding ratio and a control method of the rice cooker of embodiment 7.

Fig. 21 is a flowchart showing the 1 st pressurizing process of the rice cooker of embodiment 2.

Fig. 22 is a flowchart illustrating the 1 st depressurization step of the rice cooker of embodiment 2.

Fig. 23 is a flowchart showing the 2 nd pressurizing and depressurizing step of the rice cooker of embodiment 2.

Fig. 24 is a timing chart showing pressure changes in the boiling process of the rice cooker of example 8.

Fig. 25 is a timing chart showing pressure changes in the boiling process of the rice cooker of example 9.

Description of the reference symbols

1: a rice cooker; 2: a rice cooker main body; 2 a: a housing; 2 b: a handle; 2 c: an outer cover mounting part; 3: an outer cover; 3 a: an operation section; 3 b: an open-close button; 4: a steam release section; 4 a: steam ports (pressure valves); 5: cooking; 6: an inner cover; 10: a pan accommodating section; 11: a heating coil (heating section); 11 a: a bottom surface heating coil (heating unit); 11 b: a side heating coil (heating unit); 12: an inverter circuit; 13 a: a pressure adjusting part; 13: a pressure adjustment part; 14: a steam unit; 15: a display unit; 20: a control unit; 20 a: a memory (storage unit); 21: a pot temperature detection unit; 22: a pressure detection unit; 23: a power supply voltage detection unit; 24: a time measuring unit.

Detailed Description

Hereinafter, embodiments disclosed herein will be described with reference to the drawings. The embodiments described below are all general or specific examples. The numerical values, shapes, materials, structural elements, arrangement positions of the structural elements, connection modes, and the like shown in the following embodiments are examples, and are not intended to limit the disclosure herein. Among the components of the following embodiments, those not recited in the independent claims representing the uppermost concept will be described as arbitrary components.

The drawings are schematic and are not necessarily strictly illustrated. In the drawings, the same reference numerals are given to the substantially same components, and redundant description may be omitted or simplified.

(embodiment mode 1)

In the present embodiment, an induction heating type rice cooker is taken as an example of the rice cooker 1. The induction heating type rice cooker 1 heats a pot by supplying a high-frequency current to a heating coil to cook rice. The rice cooker 1 may not be an induction heating type rice cooker, but may be a heater type rice cooker for heating a pot by an electric heater, for example.

Fig. 1A is an external perspective view of the rice cooker 1 of the present embodiment. Fig. 1B is an exploded perspective view of the rice cooker 1 of the present embodiment. In fig. 1B, (a) shows the steam releasing part 4, (B) shows the outer lid 3, (c) shows the inner lid 6, (d) shows the pot 5, and (e) shows the rice cooker main body 2.

As shown in fig. 1A and (a) to (e) of fig. 1B, the rice cooker 1 has a rice cooker body 2 and an outer lid 3. The outer lid 3 is openably and closably attached to the upper side of the rice cooker main body 2. In a state where the outer lid 3 is closed, as shown in fig. 1A, the case 2a of the rice cooker body 2 and the outer lid 3 can be seen from the outside. A handle 2b for moving the rice cooker 1 is attached to the rice cooker main body 2.

As shown in fig. 1B (e), the rice cooker main body 2 includes a housing 2a and a pot housing portion 10 that houses a pot 5 described later. A recess having a shape conforming to the shape of the pan 5 is formed in the pan housing section 10. In the pot storage section 10, a bottom surface of the storage section in contact with the bottom surface of the pot 5 and a side surface of the storage section in contact with the side surface of the pot 5 are formed of, for example, a resin material having high heat resistance. A heating coil 11 described later is disposed inside the rice cooker main body 2 of the pot accommodating portion 10. In the present embodiment, the heating coil 11 is an example of a heating unit.

As shown in fig. 1A and 1B (B), the outer lid 3 is disposed above the rice cooker main body 2. The outer lid 3 is openably and closably attached to the rice cooker main body 2 by an outer lid attachment part 2c provided to the rice cooker main body 2. As shown in fig. 1A, the outer cover 3 is provided with an operation portion 3a and an opening/closing button 3 b.

The operation unit 3a is a part for selecting a cooking start, a cooking menu, and the like, for example, and performing an operation and a display. The operation unit 3a is provided with a display unit 15, and the display unit 15 displays operation contents, a cooking state, and the like. For example, the user can select a cooking menu corresponding to the texture such as hardness, viscosity, and firmness, and the taste (the desired state of the cooked object) by operating the operation unit 3a while viewing the display unit 15. The operation unit 3a may be a touch panel type operation unit 3a also serving as a display unit.

The opening/closing button 3b is a button for opening the outer lid 3. The user presses the open/close button 3b to rotate the outer lid 3 about the outer lid mounting part 2c, thereby opening the upper part of the rice cooker body 2. In addition, when closing the outer lid 3, the user can close the outer lid 3 by pressing the outer lid 3 in the direction of the rice cooker body 2.

As shown in fig. 1A and 1B (a), a steam release portion 4 is provided in a part of the outer cover 3. The steam release portion 4 is provided with a steam port 4a functioning as a pressure valve. Gas (water vapor) in the pot 5 is released from the steam port 4a during cooking. And, the user can detach the steam release part 4 from the outer cover 3.

Further, the rice cooker 1 has a pot 5 and an inner lid 6 inside the rice cooker surrounded by the rice cooker body 2 and the outer lid 3.

The pot 5 is a container for cooking rice by storing and heating an object to be cooked such as rice and water. The pot 5 is made of, for example, metal, ceramic coated with metal, or the like. The pot 5 is received in a pot receiving part 10 provided in the rice cooker main body 2.

The inner lid 6 is disposed on the surface of the outer lid 3 on the side of the rice cooker main body 2, and covers the upper portion of the pot 5 accommodated in the pot accommodating portion 10 to seal the pot 5. The inner lid 6 is provided with a part 13a of a pressure adjustment unit for adjusting the internal pressure of the cooker 5. The pressure adjustment portion 13 is constituted by a part 13a of the pressure adjustment portion and the steam release portion 4. That is, the part 13a of the pressure adjustment portion and the steam releasing portion 4 are part of the pressure adjustment portion 13. The pressure adjusting unit 13 adjusts the pressure by opening and closing the steam port 4a of the steam releasing unit 4.

Fig. 2 is a block diagram showing the structure of the rice cooker 1 of the present embodiment. As shown in fig. 2, the rice cooker 1 includes a heating coil 11, an inverter circuit 12, a power supply board, a power supply line, and the like in a rice cooker main body 2 as electronic components and the like necessary for the induction heating type rice cooker. The rice cooker 1 includes a control unit 20 for performing rice cooking control, a pot temperature detection unit 21, a pressure detection unit 22, a power supply voltage detection unit 23, and a time measurement unit 24 in the rice cooker main body 2.

The control unit 20 adjusts heating power for the pan 5 by the heating coil 11 via the inverter circuit 12, and controls the temperature in the pan 5. The control unit 20 controls the operation of at least one of the pressure adjustment unit 13, the steam unit 14, and the display unit 15 based on the temperature in the pot 5 transmitted from the pot temperature detection unit 21, the pressure in the pot 5 transmitted from the pressure detection unit 22, the power supply voltage transmitted from the power supply voltage detection unit 23, and the time transmitted from the time measurement unit 24. By this control, the control unit 20 performs a plurality of steps in the cooking step by the rice cooker 1. The cooking step is an example of a cooking step, and hereinafter referred to as a cooking step.

The control unit 20 has a memory 20a as a storage unit, and performs control according to a control mode stored in the memory 20 a. The control unit 20 may perform control in accordance with an operation input from the outside through the operation unit 3 a. The memory 20a may not be provided in the control unit 20, or may be provided outside the control unit 20.

The memory 20a is a storage unit that stores control modes and other control parameters during cooking. The memory 20a stores cooking menus, control modes corresponding to the respective cooking menus, adjustment parameters such as pressure and time at the time of pressurization and depressurization, and adjustment parameters such as temperature and time at the time of heating. The memory 20a stores a reference curve of pressure change at the time of pressurization and a reference curve of pressure change at the time of depressurization. Here, the state of an appropriate water addition ratio (details will be described later) corresponding to each cooking menu is set as a reference state. The reference curve at the time of pressurization is a curve represented by a ratio of a change in pressure at the time of pressurization in a reference state to time. The reference curve at the time of pressure reduction is a curve represented by a ratio of a pressure change at the time of pressure reduction in a reference state to time.

The memory 20a stores a pressure value based on a detection result of the pressure detecting unit 22, which will be described later. The memory 20a stores the pressure based on the detection result of the pressure detecting unit 22 together with the time when the pressure is detected. The time at which the pressure is detected is, for example, an elapsed time from a reference time, which is a reference time at the start of pressurization or depressurization. The elapsed time is measured by the time measuring unit 24. The memory 20a stores the change in pressure at the time of pressurization with respect to the time measured by the time measuring unit 24 as data of a pressure change curve. The memory 20a stores the change in pressure at the time of pressure reduction with respect to the time measured by the time measuring unit 24 as data of a pressure change curve.

The water adding ratio refers to the weight ratio of the cooked material to the water in the pot 5. Here, the material to be cooked is rice, for example. The water defined in calculating the water addition ratio is water that is not absorbed by the cooking material such as rice. When the water addition ratio is high, the amount of water in the boiler 5 is large, and when the water addition ratio is low, the amount of water is small. When the water addition rate is high, the change in pressure with respect to time is gentle compared to the change in pressure shown in the reference curve. In the case where the water addition ratio is low, the change in pressure with respect to time is steep as compared with the pressure change shown in the reference curve. By detecting the pressure change, the remaining water amount in the pot 5 can be detected.

The heating coil 11 is an electromagnetic coil for heating the pan 5, and generates electromagnetic induction by a high-frequency current supplied from a power supply. Thereby, the pan 5 is inductively heated by the heating coil 11, and the pan 5 is heated. In addition, the heating for the pan 5 may be not induction heating but heater type heating.

The heating coil 11 has: a bottom surface heating coil 11a that heats the bottom surface of the pan 5; and a side heating coil 11b for heating the side of the pan 5. The bottom surface heating coil 11a is wound in an annular shape and is disposed on the bottom surface of the receiving portion of the pot receiving portion 10. The side heating coil 11b is wound around a part of the side of the receiving section of the pot receiving section 10. For example, the side heating coil 11b is wound around the side surface of the storage section at a position close to the bottom surface of the storage section. By heating the pan 5 with the bottom surface heating coil 11a, internal convection is generated inside the pan 5. The internal convection is a convection in which heat rises from the center of the pot 5 and is transferred to the outside. Then, the pan 5 is heated by the side heating coil 11b, thereby generating external convection inside the pan 5. The external convection is a convection in which heat rises from the outside of the pot 5 and is transferred toward the center. By switching the bottom heating coil 11a and the side heating coil 11b at high speed and repeating the internal convection and the external convection, the material to be cooked inside the pot 5 can be vibrated and heat can be uniformly transmitted to the entire pot 5.

The heating coil 11 is not limited to the bottom heating coil 11a and the side heating coil 11 b. For example, the heating coil 11 may be disposed in another portion such as the inner lid 6.

The inverter circuit 12 controls high-frequency currents supplied to the bottom heating coil 11a and the side heating coil 11b, and switches the bottom heating coil 11a and the side heating coil 11b at high speed. The inverter circuit 12 adjusts the heating power of the pan 5 by changing the energization ratio between the bottom heating coil 11a and the side heating coil 11b under the control of the control unit 20. The currents applied to the bottom heating coils 11a and the side heating coils 11b are supplied from a power supply substrate (not shown) to the bottom heating coils 11a and the side heating coils 11 b. The power supply board receives predetermined power from a commercial power supply and generates a high-frequency current. The inverter circuit 12 switches the opening and closing of the steam port 4a of the steam release unit 4 of the pressure adjustment unit 13. The inverter circuit 12 may be disposed on the power supply board.

The pressure adjustment unit 13 adjusts the pressure inside the boiler 5 by adjusting the amount of steam inside the boiler 5. As described above, the pressure adjustment portion 13 includes the steam release portion 4. When the internal convection and the external convection are repeated in the pot 5, the pressure adjusting unit 13 adjusts the pressure in the pot 5 to generate a vigorous boiling in the pot 5, thereby vibrating the material to be cooked in the pot 5 more vigorously. The steam port 4a constitutes a pressure valve. The steam port 4a may be configured as a valve that is mechanically opened or closed, for example. The valve may release water vapor at a certain release amount when the vapor port 4a is in an open state. The steam port 4a may be configured as a valve to which an elastic body such as a spring is attached. In this valve, the open/close state of the steam port 4a can be adjusted by changing the stress applied to the elastic body of the steam port 4 a. This allows the valve to adjust the amount of water vapor released.

More specifically, the pressure adjustment unit 13 increases the temperature in the boiler 5 to, for example, 105 ℃ by pressurizing the interior of the boiler 5 to, for example, 1.2 atmospheres with the steam port 4a of the steam release unit 4 closed. This enables the hot water and water to permeate into the center of the material to be cooked. Then, the pressure adjustment part 13 opens the steam port 4a of the steam release part 4 to release the steam to the outside of the rice cooker 1. Thereby, the pressure in the pot 5 is reduced to 1.0 atmosphere at a time, for example, and the boiling point of water in the pot 5 is reduced to 100 ℃. Thus, bumping occurs in the pot 5, and the material to be cooked is vigorously vibrated and uniformly heated.

The steam unit 14 is a part that supplies steam into the pot 5 in a steaming process described later. The steam unit 14 includes, for example, a water tank (not shown) and a heater (not shown). The steam unit 14 heats water stored in the water tank in advance by a heater to form steam of, for example, 220 ℃, and sprays the steam into the boiler 5 at a high speed. Therefore, the cooked object in the pot 5 can be covered by the water vapor, and the tightness of the cooked object is improved.

The pot temperature detecting unit 21 is a temperature sensor disposed at the bottom of the pot 5, and the pot temperature detecting unit 21 detects the temperature of the contents in the pot 5 and transmits the temperature to the control unit 20.

The pressure detecting unit 22 is a pressure sensor disposed on the cooker side of the inner lid 6, and the pressure detecting unit 22 detects the pressure in the cooker 5 and transmits the pressure to the control unit 20. The pressure detection unit 22 detects whether the gradient of the pressure change (i.e., the change in pressure with respect to time) is steep or gentle in the boiling step.

The power supply voltage detection unit 23 is a voltmeter that detects the power supply voltage applied from the power supply substrate to the heating coil 11, and transmits the detected voltage to the control unit 20.

The time measuring unit 24 is a timer for measuring the time of each step during cooking. The time measuring unit 24 measures, for example, a pressurization time, a depressurization time, a heating time, and the like. The time measuring unit 24 transmits the measured time to the control unit 20.

The pressurization time is, for example, a time from the time of starting pressurization to the time of starting depressurization. For example, the pressurization time includes a period in which the pressure is increased from the atmospheric pressure and a period in which the atmospheric pressure higher than the atmospheric pressure is maintained. The decompression time is, for example, a time from a time when the decompression is started to a time when the atmospheric pressure is reached. When the pressure is reduced to a predetermined pressure lower than the atmospheric pressure, the pressure reduction time may be set to a time from a time point at which the pressure reduction is started to a time point at which the predetermined pressure is reached.

In the rice cooker 1 of the present embodiment, the control unit 20 controls at least one of the heating coil 11 and the pressure adjustment unit 13 in accordance with the gradient of the pressure change curve in the boiling step. The gradient of the pressure change curve is calculated from the pressure detected by the pressure detection unit 22 in the boiling step, and is stored in the memory 20 a. Specifically, first, the control unit 20 compares whether or not the pressure detected by the pressure detection unit 22 is gentler than the pressure change of a pressure change curve as a reference (hereinafter, referred to as a reference curve). The reference curve is a preset pressure change curve stored in the memory 20 a. That is, the control unit 20 determines whether the gradient of the pressure change curve based on the detection result of the pressure detection unit 22 is gentler or steeper than the gradient of the reference curve. At this time, the control unit 20 may detect a difference between the water addition ratio corresponding to the pressure change curve based on the detection result of the pressure detection unit 22 and the water addition ratio corresponding to the reference curve. In the present embodiment, the control unit 20 detects the water addition ratio of the material to be cooked as follows. The control unit 20 performs control according to the water addition ratio and the control pattern stored in the memory 20 a.

Specifically, the control unit 20 corrects at least any one of the heating power, the pressure, the time, and the like stored in the memory 20a based on whether or not the gradient of the pressure change curve based on the detection result of the pressure detection unit 22 is gentler than the gradient of the reference curve. For example, when the gradient of the pressure change curve based on the detection result of the pressure detection unit 22 is gentler than the gradient of the reference curve, the control unit 20 determines that the water addition ratio is high. The control unit 20 controls at least one of the heating coil 11 and the pressure adjustment unit 13 so as to increase the heating power and the pressure. The adjustment parameters such as the heating power, pressure, and time at this time may be adjusted by using a preset correction value. When the gradient of the pressure change curve based on the detection result of the pressure detection unit 22 is steeper than the gradient of the reference curve, the control unit 20 determines that the water addition ratio is low. The control unit 20 controls at least one of the heating coil 11 and the pressure adjustment unit 13 so as to reduce the heating power and the pressure. The adjustment parameters such as the heating power, pressure, and time at this time may be adjusted by using a preset correction value.

Here, in the case of performing control using the difference between the water addition ratio corresponding to the pressure change curve based on the detection result of the pressure detection unit 22 and the water addition ratio corresponding to the reference curve, the control unit 20 may correct at least one adjustment parameter of the heating power, the pressure, the time, and the like based on the reference value when the detected difference is larger than a preset set value. The reference value is stored in the memory 20 a. When the adjustment parameter is corrected, the control unit 20 may determine a weighted correction value from the difference and change the adjustment parameter using the correction value.

Fig. 3A is a diagram showing the pressurization gradient of the rice cooker of the present embodiment. Fig. 3B is a graph showing the decompression gradient of the rice cooker of the present embodiment. A straight line M1 shown in fig. 3A is a reference curve at the time of pressurization in the case of a preset and appropriate water addition ratio. A straight line M2 shown in fig. 3B is a reference curve at the time of pressure reduction in the case of a preset and appropriate water addition ratio.

In fig. 3A, a straight line H1 is a pressure change curve at the time of pressurization in the case where the water addition ratio is high. When the water addition ratio is high, the pressure in the boiler 5 rises gradually with respect to the pressurization time. That is, in the pressure change curve at the time of pressurization, the gradient of the pressure rise in the pot 5 is gentle. Therefore, when the gradient of the pressure change curve during pressurization (hereinafter referred to as a pressurization gradient) based on the detection result of the pressure detection unit 22 is gentler than the pressurization gradient of the reference curve, the control unit 20 determines that the water addition ratio is high. In fig. 3A, a straight line L1 is a pressure change curve during pressurization when the water addition ratio is low. When the water addition ratio is low, the pressure in the pot 5 rises steeply with respect to the pressurization time. That is, in the pressure change curve at the time of pressurization, the gradient of the pressure rise in the pot 5 is steep. Therefore, when the gradient of the pressure change curve during pressurization (that is, the pressurization gradient) based on the detection result of the pressure detection unit 22 is steeper than the pressurization gradient of the reference curve, the control unit 20 determines that the water addition ratio is low.

Similarly, in fig. 3B, a straight line H2 is a pressure change curve at the time of pressure reduction in the case where the water addition ratio is high. When the water addition ratio is high, the pressure in the boiler 5 gradually decreases with respect to the decompression time. That is, in the pressure change curve at the time of pressure reduction, the gradient of pressure reduction in the pan 5 is gentle. Therefore, when the gradient of the pressure change curve during pressure reduction (hereinafter referred to as a reduced pressure gradient) based on the detection result of the pressure detection unit 22 is gentler than the reduced pressure gradient of the reference curve, the control unit 20 determines that the water addition ratio is high. In fig. 3B, a straight line L2 is a pressure change curve at the time of pressure reduction when the water addition ratio is low. When the water addition ratio is low, the pressure in the pot 5 drops steeply with respect to the decompression time. That is, in the pressure change curve at the time of depressurization, the gradient of the pressure decrease in the pan 5 is steep. Therefore, when the gradient of the pressure change curve (pressure reduction gradient) at the time of pressure reduction based on the detection result of the pressure detection unit 22 is steeper than the pressure reduction gradient of the reference curve, the control unit 20 determines that the water addition ratio is low.

The pressurization gradient and the depressurization gradient are not limited to straight lines as shown in fig. 3A and 3B, and may be curved lines.

The control unit 20 calculates a water addition ratio by time and pressure, and controls at least one of the inverter circuit 12 and the pressure adjustment unit 13 based on the calculated water addition ratio to adjust at least one of the pressure and the heating power. The pressure is adjusted by controlling at least one of the heating coil 11 and the pressure adjusting portion 13. The temperature is adjusted by controlling at least one of the heating coil 11 and the pressure adjusting unit. Thus, the rice cooking device 1 can cook rice suitable for the contents, and improve the taste of the cooked object.

The rice cooking operation of the rice cooking device 1 will be explained below. Fig. 4 is a flowchart illustrating a cooking process of the rice cooker of the present embodiment.

As shown in fig. 4, the cooking operation is performed in the order of the boiling step (step S10), the high temperature maintaining step (step S20), and the steaming step (step S30).

The boiling step is a step of: the contents in the pot 5 (that is, the material to be cooked and the water not absorbed by the material to be cooked) are heated while being pressurized or depressurized, and the amount of water in the pot 5 to which the material to be cooked is boiled is dried (so-called boil-dry). The temperature at which the water in the boiler 5 dries is referred to as the boil-dry temperature. The pressure in the pot 5 in the boiling step is, for example, 1.0 to 1.2 atmospheres, and the temperature in the pot 5 in the boiling step is, for example, 100 to 105 ℃. And a boiling-out process is carried out at the end of the boiling process. The pressure in the pot 5 in the boiling-off step is, for example, 1.0 atm. The temperature in the pot 5 in the step of boiling to dry is, for example, about 130 ℃. Further, the dry-out step may be performed at the start of the high-temperature maintaining step.

The high-temperature maintaining step is a step of: after the water in the pot 5 is dried, a predetermined temperature equal to or lower than the boil-off temperature (for example, 130 ℃) is maintained.

The steaming step is a step of lowering the temperature of the material to be cooked to a steaming temperature (for example, 90 to 95 ℃). The steaming temperature is lower than the boiling point of the material to be cooked and higher than the heat preservation temperature (for example, 72-76 ℃). In the steaming step, heat may be continued as necessary.

Fig. 5A is a flowchart illustrating a boiling process of the rice cooker of the present embodiment. Fig. 5B is a timing chart showing a pressure change and a temperature change in the boiling process of the rice cooker of the present embodiment, in which (a) shows a pressure change and (B) shows a temperature change.

As shown in fig. 5A and 5B, in the boiling process, after the preheating and the preliminary heating are performed, the 1 st pressurization (step S11), the 1 st depressurization (step S12), the 2 nd pressurization and depressurization (hereinafter, referred to as pressurization and depressurization) (step S13), the 3 rd pressurization and depressurization (step S14), the 4 th pressurization and depressurization (step S15), and the boil-off (step S16) processes are performed. In each step, not only the pressure but also the temperature is adjusted.

The preheating step is as follows: in order to sufficiently permeate water into the material to be cooked, the interior of the pot 5 is maintained at a preheating temperature (for example, 40 to 60 ℃) for a predetermined preheating time. The preheating temperature is a temperature higher than room temperature and lower than the boiling point of the contents. At this time, the steam port 4a is opened. As shown in fig. 5B (a), the pressure in the pot 5 is atmospheric pressure (1.0 atm). By heating the pan 5 with the heating coil 11, the temperature in the pan 5 gradually rises as shown in fig. 5B (B).

The preheating step is a step of raising the temperature and pressure in the pot 5 until the contents are boiled. By closing the steam port 4a and heating the water by the heating coil 11, the water is gradually evaporated, and the pressure in the boiler 5 rises as shown in fig. 5B (a). The temperature in the pot 5 also rises.

Fig. 6 is a flowchart illustrating the 1 st pressurization process of the rice cooker of the present embodiment. Fig. 7 is a flowchart illustrating the 1 st depressurizing step of the rice cooker of the present embodiment.

In the following steps, the following will be described as an example of the control of the present embodiment: correction values of heating power, pressure, time, and the like are calculated using a difference between a water addition ratio corresponding to a pressure change curve based on a detection result of the pressure detecting unit 22 and a water addition ratio corresponding to a reference curve, and control is performed using the calculated correction values. The control unit 20 may determine whether the gradient of the pressure change curve based on the detection result of the pressure detection unit 22 is gentler or steeper than the gradient of the reference curve, and may perform control using a preset correction value according to the determination result. Thus, the taste of the cooked object can be improved by simple control.

As shown in fig. 6, in the 1 st pressurizing step, first, the detection of the pressurizing gradient is started (step S1101). In the detection of the pressurization gradient, the time after the start of the 1 st pressurization is measured by the time measuring unit 24, and the pressure in the pot 5 is detected by the pressure detecting unit 22. The measured time and the detected pressure are stored in the memory 20 a. This detection is performed a predetermined number of times, for example, every 0.2s from the start of the 1 st pressurization, and the relationship between time and pressure is stored in the memory 20a as a pressure change curve. That is, the pressure change curve represents the change in pressure with respect to time.

Next, the control unit 20 compares the detected pressure change curve during pressurization with a preset reference curve during pressurization (step S1102). If it is determined that the detected pressure change curve during pressurization is steeper than the reference curve, that is, the pressure does not rise gently from the reference curve (no in step S1102), the control unit 20 determines that the water addition ratio is low (step S1110). The control unit 20 sets the absolute value of the difference between the detected pressure change curve during pressurization and the reference curve as y. For example, the difference is a difference in the pressurizing time taken until a certain pressure is reached between the actual pressurizing time and the reference pressurizing time.

The control unit 20 determines whether y is larger than a preset set value, and performs the cooking process by correcting at least one of adjustment parameters such as heating power, pressure, and time based on the reference value when y is larger than the set value. As described above, the reference value is set in the control mode stored in the memory 20 a. When y is smaller than the set value, the rice cooking process is performed without changing the adjustment parameter based on the reference value.

Next, the control unit 20 performs the heating power adjustment of the 1 st time (step S1111). When y is larger than the set value a0 (yes in step S1111), the control unit 20 performs control to decrease, i.e., reduce the heating power (step S1112). Specifically, the control unit 20 sets the heating power obtained by multiplying the reference value of the heating power by the coefficients a0 and y as a correction value (that is, the correction heating power is the reference value × a0 × y), and adds the correction heating power to the reference value of the heating power. Then, the control unit 20 controls the heating coil 11 so that the heating power is the heating power added with the correction heating power. The coefficient a0 is a preset value (negative value). When y is equal to or less than the setting value a0 (no in step S1111), the control unit 20 does not change the heating power based on the heating power of the preset reference value (step S1113).

Next, the control unit 20 performs the 1 st pressurization width adjustment (step S1114). The pressure increase width is a width of a pressure change in the boiler 5, and is a width of a pressure from a pressure at the start of boiling to a predetermined pressure. The control unit 20 controls the pressure adjustment unit 13 to change the pressure value in the pot 5 according to the determined pressurization width. When y is larger than the set value B0 (yes in step S1114), the control unit 20 performs control to increase the pressurization width (step S1115). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients b0 and y as a correction value (that is, the correction value is the correction pressurization width × b0 × y), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient b0 is a preset value (positive value). When y is equal to or less than the set value B0 (no in step S1114), the control unit 20 does not change the pressurization width in accordance with the pressurization width of the preset reference value (step S1116).

Subsequently, the control unit 20 performs the 1 st decompression start time adjustment (step S1117). The decompression start time is a time from when the pressure is increased by the above-described pressure increase width to when the decompression is started after the predetermined pressure is maintained. The time for maintaining the predetermined pressure varies depending on the decompression start time. When y is greater than the set value C0 (yes in step S1117), the control unit 20 advances the start timing of the pressure reduction, that is, performs control to shorten the time for maintaining the predetermined pressure (step S1118). Specifically, the control unit 20 multiplies the reference value of the decompression start time by the coefficients c0 and y to obtain a correction value (that is, the correction value is the correction time for the decompression start time is the reference × c0 × y), and adds the correction time for the decompression start to the reference value of the decompression start time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the decompression start time is a time obtained by adding the correction time for the decompression start. The coefficient c0 is a preset value (negative value). When y is equal to or less than the set value C0 (no in step S1117), the control unit 20 does not change the decompression start time based on the decompression start time of the preset reference value (step S1119).

When determining that the pressure of the detected pressure change curve during pressurization has increased more gradually than the pressure of the reference curve (yes in step S1102), the control unit 20 determines that the water addition ratio is high (step S1120). The control unit 20 sets the absolute value of the difference between the detected pressure change curve during pressurization and the reference curve as x.

The control unit 20 determines whether x is larger than a preset set value, and performs a cooking process by correcting at least one of adjustment parameters such as heating power, pressure, and time based on the reference value when x is larger than the set value. The reference value is set in the control mode stored in the memory 20 a. When x is smaller than the set value, the rice cooking process is performed without changing the adjustment parameter based on the reference value.

Next, the control unit 20 performs heating power adjustment for the 1 st time (step S1121). When x is larger than the setting value AA0 (yes in step S1121), the control unit 20 performs control to increase the heating power, that is, to increase the heating power (step S1122). Specifically, the control unit 20 sets the heating power obtained by multiplying the reference value of the heating power by the coefficients aa0 and x as a correction value (that is, the correction heating power is the reference × aa0 × x), and adds the correction heating power to the reference value of the heating power. Then, the control unit 20 controls the heating coil 11 so that the heating power is the heating power added with the correction heating power. The coefficient aa0 is a preset value (positive value). When x is equal to or less than the setting value AA0 (no in step S1121), the control unit 20 does not change the heating power according to the heating power of the preset reference value (step S1123).

Next, the control unit 20 performs the 1 st pressurization width adjustment (step S1124). When x is larger than the set value BB0 (yes in step S1124), the controller 20 performs control to decrease the pressurization width (step S1125). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients bb0 and x as a correction value (that is, the correction value is the correction pressurization width is the reference × bb0 × x), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient bb0 is a predetermined value (negative value). If x is equal to or less than the set value BB0 (no in step S1124), the control unit 20 does not change the pressurization width in accordance with the pressurization width of the preset reference value (step S1126).

Next, the control unit 20 performs the 1 st decompression start time adjustment (step S1127). When x is greater than the set value CC0 (yes in step S1127), the control unit 20 delays the start of the pressure reduction, that is, extends the time for maintaining the predetermined pressure (step S1128). Specifically, the controller 20 multiplies the reference value of the decompression start time by the coefficients cc0 and x to obtain a correction value (that is, the correction value is the correction time for the decompression start time is the reference × cc0 × x), and adds the correction time for the decompression start to the reference value of the decompression start time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the decompression start time is a time obtained by adding the correction time for the decompression start. The coefficient cc0 is a preset value (positive value). When x is equal to or less than the set value CC0 (no in step S1127), the control unit 20 does not change the decompression start time based on the decompression start time of the preset reference value (step S1129).

The control unit 20 may adjust the decompression completion time in accordance with the adjustment of the 1 st decompression start time. That is, the decompression completion time may be set according to the water addition ratio at the time of pressurization. For example, when the ratio of water added at the time of pressurization is low, the depressurization completion time may be delayed, that is, the time for continuing the depressurization may be extended. When the ratio of water added during pressurization is high, the time for completion of depressurization may be advanced, that is, the time for continuing depressurization may be shortened.

Here, the 1 st pressurization step is ended, and then the 1 st depressurization step is started.

As shown in fig. 7, in the 1 st decompression step, first, detection of a decompression gradient is started (step S1201). In the detection of the pressure reduction gradient, the time after the start of the 1 st pressure reduction is measured by the time measuring unit 24, and the pressure in the pot 5 is detected by the pressure detecting unit 22. Then, the measured time and the detected pressure are stored in the memory 20 a. This detection is performed a predetermined number of times, for example, every 0.2s from the start of the 1 st decompression, and the relationship between time and pressure is stored in the memory 20a as a pressure change curve. That is, the pressure change curve represents the change in pressure with respect to time.

Next, the control unit 20 compares the detected pressure change curve at the time of pressure reduction with a preset reference curve at the time of pressure reduction (step S1202). Then, if it is determined that the pressure change curve at the time of the detected pressure reduction is steeper than the reference curve, that is, the pressure does not decrease more gently than the reference curve (no in step S1202), the control unit 20 determines that the water addition ratio is low (step S1210). The control unit 20 sets the absolute value of the difference between the detected pressure change curve at the time of pressure reduction and the reference curve to Y.

The control unit 20 determines whether Y is larger than a preset set value, and performs a cooking process by correcting at least one of adjustment parameters such as heating power, pressure, and time based on the reference value when Y is larger than the set value. The reference value is set in the control mode stored in the memory 20 a. When Y is smaller than the set value, the control unit 20 performs the cooking process without changing the adjustment parameter based on the reference value.

Subsequently, the control unit 20 performs the heating power adjustment of the 1 st time (step S1211). When Y is larger than the set value a1 (yes in step S1211), the control unit 20 performs control to reduce the heating power (step S1212). Specifically, the control unit 20 sets the heating power obtained by multiplying the reference value of the heating power by the coefficients a1 and Y as a correction value (that is, the correction heating power is the reference × a1 × Y)), and adds the correction heating power to the reference value of the heating power. Then, the control unit 20 controls the heating coil 11 so that the heating power is the heating power added with the correction heating power. The coefficient a1 is a preset value (negative value). When Y is equal to or less than the set value a1 (no in step S1211), the control unit 20 does not change the heating power according to the heating power of the preset reference value (step S1213).

When it is determined that the pressure of the pressure change curve at the time of the detected pressure reduction has decreased more gently than the pressure of the reference curve (yes in step S1202), the control unit 20 determines that the water addition ratio is high (step S1220). The control unit 20 sets the absolute value of the difference between the detected pressure change curve at the time of pressure reduction and the reference curve to X.

The control unit 20 determines whether or not X is larger than a preset set value, and performs a cooking process by correcting at least one of adjustment parameters such as heating power, pressure, and time based on a reference value when X is larger than the set value. The reference value is set in the control mode stored in the memory 20 a. When X is smaller than the set value, the cooking process is performed without changing the adjustment parameter based on the reference value.

Next, the control unit 20 determines whether X is larger than the set value AAA where the flush occurs (step S1221). If X is greater than the set value AAA (yes in step S1221), there is a possibility that flooding will occur, and therefore the control unit 20 stops heating and reduces the pressure to the pressure in the boiler 5, which is temporarily at atmospheric pressure. Further, the controller 20 opens the steam port 4a to release the remaining steam to the outside. After that, the control unit 20 heats the heating coil 11 according to the original heating power (step S1222).

When X is equal to or less than the setting value AAA (no in step S1221), the control unit 20 determines whether X is greater than the setting value AA1 (step S1223). When X is larger than the setting value AA1 (yes in step S1223), the control unit 20 performs control to increase the heating power (step S1224). Specifically, the control unit 20 sets the heating power obtained by multiplying the reference value of the heating power by the coefficients aa1 and X as a correction value (that is, the correction heating power is the reference × aa1 × X), and adds the correction heating power to the reference value of the heating power. Then, the control unit 20 controls the heating coil 11 so that the heating power is the heating power added with the correction heating power. The coefficient aa1 is a preset value (positive value). When X is equal to or less than the setting value AA1 (no in step S1223), the control unit 20 does not change the heating power in accordance with the heating power of the preset reference value (step S1225).

Here, the 1 st depressurizing step is completed, and then the 2 nd pressurizing and depressurizing (pressure increasing and reducing) step is started.

Fig. 8 is a flowchart showing the 2 nd pressurizing and depressurizing step of the rice cooker of the present embodiment. In addition, in the pressure increasing and reducing process after the 2 nd time, the pressurizing width and the pressure reducing starting time are adjusted according to the water adding proportion judged in the pressure reducing process of the 1 st time.

When the water addition ratio is low (step S1310), first, the control unit 20 adjusts the 2 nd pressurization start time (step S1311). The pressurization start time is a time from the 1 st depressurization to the restart of pressurization as described above. When Y is larger than the set value B1 (yes in step S1311), the control unit 20 performs control to advance the timing to start pressurization (step S1312). Specifically, the control unit 20 multiplies the reference value of the 2 nd pressurization start time by the coefficients b1 and Y to obtain a correction value (that is, the correction value is the correction time for the pressurization start time is the reference × b1 × Y), and adds the correction time for the pressurization start to the reference value of the pressurization start time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization start time is a time obtained by adding the correction time for starting pressurization. The coefficient b1 is a preset value (negative value). When Y is equal to or less than the set value B1 (no in step S1311), the control unit 20 does not change the 2 nd pressurization start time based on the pressurization start time of the preset reference value (step S1313).

Next, the control unit 20 performs the 2 nd pressurization width adjustment (step S1314). When Y is larger than the set value C1 (yes in step S1314), the control unit 20 performs control to increase the pressurization width (step S1315). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients c1 and Y as a correction value (that is, the correction value is the correction pressurization width × c1 × Y), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient c1 is a preset value (positive value). When Y is equal to or less than the set value C1 (no in step S1314), the control unit 20 does not change the pressing width in accordance with the pressing width of the preset reference value (step S1316).

Next, the control unit 20 performs the 2 nd decompression start time adjustment (step S1317). When Y is larger than the set value D1 (yes in step S1317), the control unit 20 performs control to delay the time to start pressure reduction (step S1318). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the decompression start time by the coefficients d1 and Y as a correction value (that is, the correction value is the correction time for the decompression start time is the reference × d1 × Y), and adds the correction time for the decompression start to the reference value of the decompression start time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the decompression start time is a time obtained by adding the correction time for the decompression start. The coefficient d1 is a preset value (positive value). When Y is equal to or less than the set value D1 (no in step S1317), the control unit 20 does not change the decompression start time in accordance with the decompression start time of the preset reference value (step S1319).

When the water addition ratio is high (step S1320), the control unit 20 performs the 2 nd pressurization start time adjustment (step S1321). When X is larger than set value BB1 (yes in step S1321), control unit 20 performs control to extend the pressurization start time (step S1322). That is, the control unit 20 performs control to delay the pressurization start timing. Specifically, the control unit 20 multiplies the reference value of the 2 nd pressurization start time by the coefficients bb1 and X to obtain a correction value (that is, the correction value is the correction time for the pressurization start is the reference × bb1 × X), and adds the correction time for the pressurization start to the reference value of the pressurization start time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization start time is a time obtained by adding the correction time for starting pressurization. The coefficient bb1 is a preset value (positive value). When X is equal to or less than the set value BB1 (no in step S1321), the control unit 20 does not change the 2 nd pressurization start time based on the pressurization start time of the preset reference value (step S1323).

Next, the control unit 20 performs the 2 nd pressurization width adjustment (step S1324). When X is larger than the set value CC1 (yes in step S1324), the control unit 20 performs control to decrease the pressurization width (step S1325). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients cc1 and X as a correction value (that is, the correction value is the correction pressurization width × cc1 × X), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient cc1 is a predetermined value (negative value). When X is equal to or less than the set value CC1 (no in step S1324), the control unit 20 does not change the pressurization width in accordance with the pressurization width of the preset reference value (step S1326).

Subsequently, the control unit 20 performs the 2 nd decompression start time adjustment (step S1327). When X is larger than the set value DD1 (yes in step S1327), the control unit 20 performs control to advance the time point at which the pressure reduction is started (step S1328). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the decompression start time by the coefficients dd1 and X as a correction value (that is, the correction value is the correction time for the decompression start time is the reference × dd1 × X), and adds the correction time for the decompression start to the reference value of the decompression start time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the decompression start time is a time obtained by adding the correction time for the decompression start. The coefficient dd1 is a predetermined value (negative value). When X is equal to or less than the set value DD1 (no in step S1327), the control unit 20 does not change the decompression start time based on the decompression start time of the preset reference value (step S1329).

Here, the 2 nd compression/decompression process is ended, and the 3 rd compression/decompression process is started. The 3 rd and subsequent pressurizing/depressurizing steps may not be performed. For example, the control unit 20 may determine whether or not to perform the pressure increasing/decreasing process based on the water addition ratio, and may determine not to perform the pressure increasing/decreasing process. In the present embodiment, a case where the 3 rd pressurizing/depressurizing step and the 4 th pressurizing/depressurizing step are performed will be described as an example. The pressure addition and reduction are not limited to the 3 rd time and the 4 th time, and the pressure addition and reduction after the 5 th time may be performed in the same manner.

Fig. 9 is a flowchart showing the 3 rd pressurizing and depressurizing step of the rice cooker of the present embodiment.

In the 3 rd pressurizing/depressurizing step, when the water addition ratio is low (step S1410), the control unit 20 performs the same control as the control performed when the water addition ratio is low at the 2 nd pressurizing start time. That is, the control unit 20 performs the 3 rd adjustment of the pressurization start time, the adjustment of the pressurization width, and the adjustment of the depressurization start time (steps S1411 to S1419). At this time, the controller 20 uses the set values B2, C2, and D2 instead of the set values B1, C1, and D1 used in the 2 nd pressure increasing and reducing process. The controller 20 uses the coefficients b2, c2, and d2 instead of the coefficients b1, c1, and d1 used in the 2 nd compression/decompression process.

When the water addition ratio is high (step S1420), the control unit 20 first determines whether or not to perform the 3 rd pressure increasing/decreasing process (step S1430). Thereby, the number of times of pressurization and depressurization performed after the 2 nd time is adjusted. When X is larger than the set value EE1 (yes in step S1430), the control unit 20 does not perform the 3 rd pressure increasing/decreasing process (step S1450). When X is equal to or less than the set value EE1 (no in step S1430), the 3 rd pressure increasing/decreasing step is performed as set (step S1440).

In the 3 rd pressurization/depressurization step, the control unit 20 performs the same control as that performed when the water addition ratio is high at the 2 nd pressurization start time. That is, the control unit 20 performs the 3 rd adjustment of the pressurization start time, the adjustment of the pressurization width, and the adjustment of the depressurization start time (steps S1441 to S1449). In this case, the controller 20 uses the set values BB2, CC2, and DD2 instead of the set values BB1, CC1, and DD1 used in the 2 nd pressure increasing/reducing process. In addition, the control unit 20 uses coefficients bb2, cc2, and dd2 instead of the coefficients bb1, cc1, and dd1 used in the 2 nd compression/decompression process.

Here, the 3 rd time pressure increasing and reducing process is ended, and then the 4 th time pressure increasing and reducing process is started. Fig. 10 is a flowchart showing the 4 th pressurizing and depressurizing step of the rice cooker of the present embodiment.

In the 4 th compression/decompression step, when the water addition ratio is low (step S1510), the control unit 20 first determines whether or not to perform the 4 th compression/decompression step (step S1520). Thereby, the number of times of pressurization and depressurization performed after the 3 rd time is adjusted. When Y is larger than the set value E1 (yes in step S1520), the control unit 20 increases the number of times of pressurization and depressurization (step S1530), and performs the pressurization and depressurization step of the 4 th time.

In the 4 th pressurization/depressurization step, the control unit 20 performs the same control as that performed when the water addition ratio is high at the 2 nd pressurization start time. That is, the control unit 20 performs the 4 th adjustment of the pressurization start time, the adjustment of the pressurization width, and the adjustment of the depressurization start time (steps S1531 to S1539). At this time, the controller 20 uses the set values B3, C3, and D3 instead of the set values B1, C1, and D1 used in the 2 nd pressure increasing and reducing process. The controller 20 uses the coefficients b3, c3, and d3 instead of the coefficients b1, c1, and d1 used in the 2 nd compression/decompression process.

When Y is equal to or less than set value E1 (no in step S1530), control unit 20 does not perform the 4 th pressure increasing/decreasing process (step S1540). When the water addition ratio is high, the control unit 20 does not perform the 4 th pressure increasing/decreasing step (step S1550).

Here, the 4 th pressure increasing and reducing step is ended, and the step of drying out is started without performing pressure increasing and reducing.

Fig. 11 is a flowchart showing a process of boiling dry in the rice cooker of the present embodiment. The dry-out refers to the drying of the water in the pot 5 (i.e., the state of 0 water adding ratio). The controller 20 adjusts the temperature of the boil-off.

When the water addition ratio is low (step S1610), the control unit 20 determines whether Y is larger than a set value E2 (step S1611). When Y is larger than the set value E2 (yes in step S1611), the controller 20 sets the boil-off temperature higher than the reference value (step S1612). Specifically, the control unit 20 multiplies the reference value of the dry temperature by the coefficients e2 and Y to obtain a correction value (that is, the correction value is the dry correction temperature is the reference × e2 × Y), and adds the dry correction temperature to the reference value of the dry temperature. Then, if the temperature detected by the pan temperature detecting unit 21 is equal to the sum of the boil-off temperature and the corrected boil-off temperature, the control unit 20 stops the heating coil 11. The coefficient e2 is a preset value (positive value). When Y is equal to or less than the set value E2 (no in step S1611), the control unit 20 does not change the boil-off temperature according to the preset reference value (step S1613).

When the water addition ratio is high (step S1620), the control unit 20 determines whether X is larger than a set value EE2 (step S1621). When X is larger than the set value EE2 (yes in step S1621), the controller 20 sets the boil-off temperature to be low (step S1622). The controller 20 multiplies the reference value of the dry-out temperature by the coefficients ee2 and X to obtain a correction value (that is, the correction value is the dry-out correction temperature × reference × ee2 × X), and adds the dry-out correction temperature to the reference value of the dry-out temperature. Then, the control unit 20 corrects the temperature of the boil-off to the temperature to which the corrected temperature of the boil-off is added. Then, if the temperature detected by the pan temperature detecting unit 21 becomes the corrected boil-off temperature, the control unit 20 stops the heating coil 11. The coefficient ee2 is a preset value (positive value). When X is equal to or less than the set value EE2 (no in step S1621), the controller 20 does not change the drying temperature according to the preset reference value (step S1623).

The boiling step is completed because the boil-off is completed.

The control unit 20 is not limited to adjusting the temperature for boiling dry based on the water addition ratio at the time of pressure reduction, and may adjust the temperature for boiling dry based on the water addition ratio at the time of pressure increase. For example, the boiling temperature may be adjusted to be high when the water addition rate during pressurization is low, and the boiling temperature may be adjusted to be low when the water addition rate during pressurization is high.

Next, the control unit 20 performs a high temperature maintaining step. Fig. 12 is a flowchart showing a high temperature maintaining process of the rice cooker of the present embodiment. In the high temperature maintaining step, the temperature and time are adjusted according to the water addition ratio determined in the 1 st depressurizing step.

When the water addition ratio is low (step S210), the control unit 20 first adjusts the temperature maintained in the high temperature maintaining step (hereinafter, referred to as a temperature adjustment temperature). The control unit 20 determines whether Y is larger than a set value a5 (step S211). When Y is larger than the set value a5 (yes in step S211), the control unit 20 sets the temperature adjustment temperature to be high (step S212). Specifically, the control unit 20 sets a temperature obtained by multiplying the reference value of the temperature-controlled temperature by the coefficients a5 and Y as a correction value (that is, the correction value is the temperature-controlled correction temperature equal to the reference × a5 × Y), and adds the temperature-controlled correction temperature to the reference value of the temperature-controlled temperature. Then, the control unit 20 controls the heating coil 11 so that the temperature-controlled temperature is the temperature to which the temperature-controlled correction temperature is added. The coefficient a5 is a preset value (positive value). When Y is equal to or less than the set value a5 (no in step S211), the control unit 20 does not change the temperature control temperature based on the preset reference value temperature control temperature (step S213).

Next, the control unit 20 adjusts the time for maintaining the temperature control temperature (hereinafter referred to as temperature control time) (step S214). When Y is larger than the set value B5 (yes in step S214), the control unit 20 sets the temperature adjustment time to be long (step S215). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the temperature adjustment time by the coefficients b5 and Y as a correction value (that is, the correction value is the correction time for temperature adjustment — reference × b5 × Y), and adds the correction time for temperature adjustment to the reference value of the temperature adjustment time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the temperature control time is a time obtained by adding the correction time for temperature control. The coefficient b5 is a preset value (positive value). When Y is equal to or less than the set value B5 (no in step S214), the control unit 20 does not change the temperature control time based on the temperature control time of the preset reference value (step S216).

When the water addition ratio is high (step S220), the control unit 20 first determines whether X is greater than a set value AA5 as the temperature adjustment (step S221). When X is larger than the set value AA5 (yes in step S221), the control unit 20 sets the temperature adjustment temperature to be low (step S222). Specifically, the control unit 20 multiplies the reference value of the temperature-controlled temperature by the coefficients aa5 and X to obtain a correction value (that is, the correction value is the temperature-controlled correction temperature equal to the reference × aa5 × X), and adds the temperature-controlled correction temperature to the reference value of the temperature-controlled temperature. Then, the control unit 20 controls the heating coil 11 so that the temperature-controlled temperature is the temperature to which the temperature-controlled correction temperature is added. The coefficient aa5 is a preset value (negative value). When X is equal to or less than the set value AA5 (no in step S221), the control unit 20 does not change the temperature control temperature based on the preset reference value temperature control temperature (step S223).

Next, the control unit 20 adjusts the temperature adjustment time (step S224). When X is larger than set value BB5 (yes in step S224), control unit 20 sets the temperature adjustment time to be short (step S225). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the temperature adjustment time by the coefficients bb5 and X as a correction value (that is, the correction value is the correction time for temperature adjustment × bb5 × X), and adds the correction time for temperature adjustment to the reference value of the temperature adjustment time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the temperature control time is a time obtained by adding the correction time for temperature control. The coefficient bb5 is a predetermined value (negative value). When X is equal to or less than the set value BB5 (no in step S224), the control unit 20 does not change the temperature adjustment time in accordance with the temperature adjustment time of the preset reference value (step S226).

After the set temperature adjustment time has elapsed, the high temperature maintaining step is ended.

Subsequently, the control unit 20 performs a steaming step. Fig. 13 is a flowchart showing a steaming process of the rice cooker of the present embodiment. In the steaming step, the time and the pressure increase width are adjusted according to the water addition ratio determined in the 1 st depressurizing step.

When the water addition ratio is low (step S310), the control unit 20 first adjusts the total time of the steaming step. The control unit 20 determines whether Y is larger than a set value a6 (step S311). When Y is larger than the set value a6 (yes in step S311), the control unit 20 sets the total time to be long (step S312). Specifically, the control unit 20 multiplies the reference value of the total time by the coefficients a6 and Y to obtain a correction value (that is, the correction value is the correction time of the total time equal to the reference × a6 × Y), and adds the correction time of the total time to the reference value of the total time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the total time is a time obtained by adding the correction time of the total time. The coefficient a6 is a preset value (positive value). When Y is equal to or less than the set value a6 (no in step S311), the control unit 20 does not change the total time based on the total time of the preset reference value (step S313).

Next, the control unit 20 adjusts the heat continuation time (step S314). When Y is larger than set value B6 (yes in step S314), control unit 20 sets the heat-continuation time to be long (step S315). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the heat continuation time by the coefficients b6 and Y as a correction value (that is, the correction value is the reference × b6 × Y), and adds the heat continuation correction time to the reference value of the heat continuation time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the heat continuation time is a time obtained by adding the correction time of the heat continuation. The coefficient b6 is a preset value (positive value). When Y is equal to or less than the set value B6 (no in step S314), the control unit 20 does not change the heat continuation time based on the preset reference value (step S316).

Next, the control unit 20 adjusts the pressurization time (step S317). When Y is larger than the set value C6 (yes in step S317), the control unit 20 sets the pressurization time to be long (step S318). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the pressurization time by the coefficients c6 and Y as a correction value (that is, the correction value is the pressurization correction time equal to the reference × c6 × Y), and adds the pressurization correction time to the reference value of the pressurization time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization time is a time after the correction time of pressurization is added. The coefficient c6 is a preset value (positive value). When Y is equal to or less than the set value C6 (no in step S317), the control unit 20 does not change the pressurization time based on the pressurization time of the preset reference value (step S319).

Next, the control unit 20 adjusts the pressurization width (step S320). When Y is larger than the set value D6 (yes in step S320), the control unit 20 sets the pressurization width to be large (step S321). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients d6 and Y as a correction value (that is, the correction value is the correction pressurization width × d6 × Y), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient d6 is a preset value (positive value). When Y is equal to or less than the set value D6 (no in step S320), the control unit 20 does not change the pressurization width in accordance with the pressurization width of the preset reference value (step S322).

When the water addition ratio is high (step S350), the control unit 20 first determines whether X is larger than a set value AA6 during adjustment of the total time of the steaming step (step S351). When X is larger than the setting value AA6 (yes in step S351), the control unit 20 sets the total time to be short (step S352). Specifically, the control unit 20 multiplies the reference value of the total time by the coefficients aa6 and X to obtain a correction value (that is, the correction value is the correction time of the total time equal to the reference × aa6 × X), and adds the correction time of the total time to the reference value of the total time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the total time is a time obtained by adding the correction time of the total time. The coefficient aa6 is a preset value (negative value). When X is equal to or less than the set value AA6 (no in step S351), the control unit 20 does not change the total time based on the total time of the preset reference value (step S353).

Next, the control unit 20 adjusts the heat continuation time (step S354). When X is larger than set value BB6 (yes in step S354), control unit 20 sets the heat continuation time to be short (step S355). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the heat continuation time by the coefficients bb6 and X as a correction value (that is, the correction value is the reference × bb6 × X), and adds the heat continuation correction time to the reference value of the heat continuation time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the heat continuation time is a time obtained by adding the correction time of the heat continuation. The coefficient bb6 is a predetermined value (negative value). If X is equal to or less than the set value BB6 (no in step S354), the control unit 20 does not change the heat duration in accordance with the heat duration of the preset reference value (step S356).

Next, the control unit 20 adjusts the pressurization time (step S357). If X is greater than the set value CC6 (yes at step S357), the control unit 20 sets the pressurization time to be short (step S358). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the pressurization time by the coefficients cc6 and X as a correction value (that is, the correction time of the pressurization is the reference × cc6 × X), and adds the correction time of the pressurization to the reference value of the pressurization time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization time is a time obtained by adding the correction time for pressurization. The coefficient cc6 is a predetermined value (negative value). If X is equal to or less than the set value CC6 (no in step S357), the control unit 20 does not change the pressurization time based on the preset reference value of the pressurization time (step S359).

Next, the control unit 20 adjusts the pressurization width (step S360). When X is larger than the set value DD6 (yes in step S360), the control unit 20 sets the pressurization width to be small (step S361). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients dd6 and X as a correction value (that is, the correction value is the correction pressurization width is the reference × dd6 × X), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient dd6 is a predetermined value (negative value). When X is equal to or less than the set value DD6 (no in step S360), the control unit 20 does not change the pressurization width in accordance with the pressurization width of the preset reference value (step S362).

After the set total time of the steaming step has elapsed, the steaming step is ended.

The set values and coefficients in the respective steps are values set in advance in accordance with a control mode corresponding to a desired state of the cooked object after cooking. The desired state of the cooked object after cooking is, for example, a cooking state corresponding to the texture and taste such as hardness, stickiness and firmness. The set values and coefficients in the above-described steps may be appropriately changed according to the pressure stored in the memory 20 a.

Here, a specific example of control corresponding to the pressure change curve at the time of pressurization or depressurization is shown.

[ example 1]

As example 1, control in which the decompression start time, which is the decompression timing after the pressurization, is changed in accordance with the water addition ratio at the time of the pressurization will be described. Fig. 14 is a time chart showing pressure changes of the rice cooker of the present embodiment. In fig. 14, a straight line M1 represents a reference curve during pressurization, a straight line H1 represents a pressure change curve during pressurization when the water addition ratio is high, and a straight line L1 represents a pressure change curve during pressurization when the water addition ratio is low.

As described above, when the control unit 20 determines that the gradient of the pressure change curve at the time of pressurization is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control such that the decompression start time is shorter than the decompression start time of the set reference value (step S1118 in fig. 6). That is, the control unit 20 performs control to advance the timing of starting the pressure reduction. The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, the control unit 20 starts the depressurization within a time shorter than the depressurization start time in the reference state determined in advance so that the depressurization can be started in a state where the amount of water in the boiler 5 is close to the amount of water at the depressurization start time in the reference state. This can prevent the cooking state of the material to be cooked from deviating from the reference state.

Specifically, in fig. 14, in the reference state shown by the straight line M1, the pressure reduction is started after the elapse of time T0 from the pressurization start time, but as shown by the straight line L1, in the case where the water addition rate is low, the pressure reduction is started after the elapse of time T1 from the pressurization start. T1 is shorter than T0.

Further, the start of the decompression is performed by: the pressure adjuster 13 is controlled by the controller 20, and the pressure adjuster 13 opens the steam port 4 a.

When the control unit 20 determines that the gradient of the pressure change curve during pressurization is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs control such that the depressurization start time becomes longer than the depressurization start time of the set reference value (step S1128 in fig. 6). The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. At this time, the amount of water in the boiler 5 is in a state of being larger than the amount of water remaining in the boiler 5 in the reference state. Therefore, the control unit 20 starts the depressurization at a time later than the depressurization start time in the reference state determined in advance so that the depressurization can be started in a state where the amount of water in the boiler 5 is close to the depressurization start time in the reference state. This can prevent the cooking state of the material to be cooked from deviating from the reference state.

Specifically, as shown by a straight line H1 in fig. 14, when the water addition ratio is high, the pressure reduction is started after a time T2 has elapsed from the pressurization start time. T2 is longer than T0.

[ example 2]

Next, as example 2, the following control is explained: after the pressure reaches a predetermined pressure, the heating power is changed according to the water addition ratio at the time of pressurization. Fig. 15 is a timing chart showing pressure changes in the boiling process of the rice cooker of the present embodiment. In fig. 15, a straight line M1 represents a reference curve during pressurization, a straight line H1 represents a pressure change curve during pressurization when the water addition ratio is high, and a straight line L1 represents a pressure change curve during pressurization when the water addition ratio is low.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressurization is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control to make the heating power smaller, that is, weaker, than the heating power of the set reference value (step S1112 in fig. 6). The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, by reducing the heating power, the evaporation of the water in the boiler 5 can be suppressed, and the water amount in the boiler 5 can be brought close to the water amount in the reference state. This can suppress the deviation of the cooking state of the object to be cooked from the reference state during pressurization.

Specifically, the control unit 20 controls the heating power of the pan 5 by the heating coil 11 through the inverter circuit 12. After the pressure in the pan 5 reaches a predetermined pressure, the control unit 20 controls the energization ratio of the heating coil 11 to change the heating power D0 from the reference state to heating power D1 weaker than heating power D0 as shown in fig. 15. Specifically, the ratio of current to the bottom surface heating coil 11a as the inner coil is reduced by increasing the ratio of current to the side surface heating coil 11b as the outer coil out of the bottom surface heating coil 11a and the side surface heating coil 11b constituting the heating coil 11. This makes it possible to reduce the heating power compared to the heating power in the reference state.

When the control unit 20 determines that the gradient of the pressure change curve during pressurization is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs control such that the heating power is larger than the set reference value of the heating power, that is, strong (step S1122 in fig. 6). The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. Therefore, the amount of water in the boiler 5 can be made closer to the reference amount of water by increasing the amount of water evaporated in the boiler 5 by increasing the heating power. This can suppress the deviation of the cooking state of the object to be cooked from the reference state during pressurization.

Specifically, the control unit 20 controls the energization ratio of the heating coil 11 by the inverter circuit 12, and after the pressure in the pan 5 reaches a predetermined pressure, changes the heating power D0 from the reference state to heating power D2 which is stronger than the heating power D0, as shown in fig. 15. Specifically, the control unit 20 increases the ratio of the current supplied to the bottom surface heating coil 11a and decreases the ratio of the current supplied to the side heating coil 11b so that the heating power becomes stronger than the heating power in the reference state.

[ example 3]

Next, as example 3, the following control is explained: the time of the pressurization and depressurization after the 2 nd time, that is, the start time of the pressurization and depressurization is changed according to the water addition ratio at the time of pressurization. In addition, the start time of the 2 nd pressurization and depressurization will be described below. Fig. 16 is a timing chart showing pressure changes in the boiling process of the rice cooker of the present embodiment. In fig. 16, a straight line M1 represents a reference curve during pressurization, a straight line H1 represents a pressure change curve during pressurization when the water addition ratio is high, and a straight line L1 represents a pressure change curve during pressurization when the water addition ratio is low.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressurization is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control such that the 2 nd time of start of pressurization is shorter than the set 2 nd time of start of pressurization (step S1312 in fig. 8). The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, the 2 nd time of starting the pressure increase/decrease is shortened so that the pressure increase/decrease is performed after the 2 nd time in accordance with the water amount assumed in the reference state. Thus, since the evaporation amount of water in the boiler 5 is small, the water amount in the boiler 5 can be made close to the water amount assumed in the reference state when the 2 nd pressurization and depressurization is started. Therefore, the deviation of the cooking state of the cooking object from the reference state can be suppressed.

Specifically, in fig. 16, in the case of the reference state shown by the straight line M1, the pressurization by the 2 nd compression and decompression is started after the elapse of the time T0 from the end of the 1 st decompression, whereas in the case of a low water addition ratio as shown by the straight line L1, the pressurization by the 2 nd compression and decompression is started after the elapse of the time T1 which is shorter than the time T0 in the reference state from the end of the 1 st decompression. The control unit 20 controls at least one of the pressure adjustment unit 13 and the heating coil 11 to set the pressurization start time of the 2 nd time of the pressure increase and decrease to a period shorter than the pressurization start time in the reference state. At this time, the control unit 20 controls the pressurization start time so that the pressurization is started when the temperature of the content in the pot 5 detected by the pot temperature detection unit 21 is equal to or lower than the boiling point of the content when the maximum pressure is applied to the inside of the pot 5.

When the control unit 20 determines that the gradient of the pressure change curve during pressurization is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs control such that the 2 nd time of start of pressurization is longer than the set 2 nd time of start of pressurization (step S1322 in fig. 8). The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. Therefore, in order to perform the pressurization and depressurization after the 2 nd time in accordance with the amount of water assumed in the reference state, the start timing of the pressurization and depressurization after the 2 nd time is delayed. Thus, the evaporation amount of water in the boiler 5 increases, and therefore, when the 2 nd pressure increase and decrease is started, the amount of water in the boiler 5 can be made closer to the amount of water assumed in the reference state. Therefore, the deviation of the cooking state of the cooking object from the reference state can be suppressed.

Specifically, as indicated by a straight line H1 in fig. 16, after a time T2 longer than the time T0 in the reference state has elapsed since the 1 st pressure reduction was completed, the 2 nd pressure reduction was started. The control unit 20 controls at least one of the pressure adjustment unit 13 and the heating coil 11 so that the pressurization start time of the 2 nd time of the pressure increase and decrease is longer than the pressurization start time in the reference state. At this time, the control unit 20 controls the pressurization start time so that the pressurization is started when the temperature of the content in the pot 5 detected by the pot temperature detection unit 21 is equal to or lower than the boiling point of the content when the maximum pressure is applied to the inside of the pot 5.

The pressure reduction and compression are not limited to the 2 nd time, and the pressure reduction and compression after the 3 rd time are also the same as the 2 nd time pressure reduction and compression.

[ example 4]

Next, as example 4, the following control is explained: the number of times of pressurization and depressurization after the 2 nd time is changed according to the ratio of water addition at the time of pressurization. Fig. 17 is a timing chart showing pressure changes in the boiling process of the rice cooker of the present embodiment. In fig. 17, a straight line M1 represents a reference curve during pressurization, a straight line H1 represents a pressure change curve during pressurization when the water addition ratio is high, and a straight line L1 represents a pressure change curve during pressurization when the water addition ratio is low.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressurization is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control such that the number of times of pressurization and depressurization after the 2 nd time is smaller than the set number of times of pressurization and depressurization after the 2 nd time. The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, by making the number of times of pressure increase and pressure decrease smaller than the number of times of pressure increase and pressure decrease in the reference state, the number of times of water absorption by the material to be cooked under pressure and pressure decrease can be reduced, and the cooked state of the material to be cooked in the pot 5 after the pressure increase and pressure decrease is completed can be made closer to the cooked state of the material to be cooked in the reference state.

Specifically, in fig. 17, the pressure increase and decrease are performed N0 times in the case of the reference state indicated by the straight line M1, but in the case of a low water addition ratio, N1 times less than N0 times in the case of the reference state are performed as indicated by the straight line L1. For example, in the case of the reference state indicated by the straight line M1, the 2 nd and 3 rd pressure reductions are performed (N0 is 2), but as indicated by the straight line L1, in the case where the water addition ratio is low, only the 2 nd pressure reduction is performed, and the 3 rd pressure reduction is not performed (N1 is 1). The control unit 20 controls at least one of the pressure adjustment unit 13 and the heating coil 11 so that the pressure reduction is performed only once after the 1 st pressure reduction. The controller 20 controls at least one of the pressure adjuster 13 and the heating coil 11 so that the 2 nd pressure reduction is followed by the subsequent step of drying.

When the control unit 20 determines that the gradient of the pressure change curve during pressurization is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs control such that the number of times of pressurization and depressurization after the 2 nd time is greater than the set number of times of pressurization and depressurization after the 2 nd time. The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. Therefore, by increasing the number of times of pressure increase and pressure decrease more than the number of times of pressure increase and pressure decrease in the reference state, the number of times of water absorption by the material to be cooked under pressure increase and pressure decrease can be increased, and the cooked state of the material to be cooked in the pot 5 after the pressure increase and pressure decrease is completed can be made closer to the cooked state of the material to be cooked in the reference state.

Specifically, in fig. 17, as indicated by a straight line H1, when the water addition ratio is high, N2 times of pressure reduction are performed more than N0 times in the case of the reference state. For example, in the case of the reference state indicated by the straight line M1, the 2 nd and 3 rd pressure increases and decreases (N0 ═ 2) are performed, whereas in the case where the water addition ratio is high, the 2 nd, 3 rd and 4 th pressure increases and decreases (N2 ═ 3) are performed, as indicated by the straight line H1. The control unit 20 controls at least one of the pressure adjustment unit 13 and the heating coil 11 so that the pressure is reduced 3 times after the 1 st pressure reduction. The control unit 20 may determine whether or not to perform the next pressure increase or decrease every time the pressure increase or decrease is completed.

[ example 5]

Next, as example 5, the following control is explained: the decompression completion time is changed according to the water addition ratio at the time of decompression. Fig. 18 is a timing chart showing pressure changes in the boiling process of the rice cooker of the present embodiment. In fig. 18, a straight line M2 represents a reference curve during pressure reduction, a straight line H2 represents a pressure change curve during pressure reduction when the water addition ratio is high, and a straight line L2 represents a pressure change curve during pressure reduction when the water addition ratio is low.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressure reduction is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control to reduce the pressure in the boiler 5 to the set pressure. The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, since it is not necessary to further reduce the amount of water in the boiler 5, the control unit 20 controls the pressure adjusting unit 13 to reduce the pressure in the boiler 5 to the set pressure. The pressure regulator 13 opens the steam port 4a until the pressure in the boiler 5 reaches a set pressure. In addition to the pressure adjustment unit 13, the control unit 20 may reduce the pressure by reducing the heating power by the heating coil 11 (step S1212 in fig. 7).

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressure reduction is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs the following control: the pressure reduction is stopped while the pressure in the boiler 5 is reduced to the set pressure, and the pressure in the boiler 5 is once increased to the original pressure and then reduced. The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. Therefore, bumping may occur in the middle of the pressure reduction to the set pressure, and flooding may occur. Therefore, the pressure in the boiler 5 is temporarily returned to the original pressure, and then, when the water addition ratio becomes low, the pressure reduction is started again. In this way, the depressurization is started at a time later than the start of the depressurization in the reference state, and the amount of water in the boiler 5 can be brought close to the amount of water in the reference state. Therefore, the occurrence of a deviation in the cooking state of the depressurized object from the reference state can be suppressed while suppressing the overflow.

Specifically, the controller 20 controls the pressure adjuster 13 so that the pressure adjuster 13 opens the steam port 4a to reduce the pressure in the boiler 5. Thereafter, the pressure adjustment unit 13 is temporarily controlled to close the steam port 4 a. Then, the pot 5 is heated again by the heating coil 11, and the pressure in the pot 5 is increased to the original pressure. Thereafter, the control unit 20 determines the water addition ratio again from the pressure reduction gradient, and when it is determined that the water addition ratio is low, controls the pressure adjustment unit 13 to reduce the pressure in the boiler 5 to the set pressure. As shown in fig. 18, the time for completion of the pressure reduction in this case is later than the time for completion of the pressure reduction in the reference state by T1.

[ example 6]

Next, as example 6, the following control is explained: after the predetermined pressure is maintained, the heating power is changed according to the water addition ratio at the time of pressure reduction. Fig. 19 is a timing chart showing pressure changes in the boiling process of the rice cooker of the present embodiment. In fig. 19, a straight line M2 represents a reference curve during pressure reduction, a straight line H2 represents a pressure change curve during pressure reduction when the water addition ratio is high, and a straight line L2 represents a pressure change curve during pressure reduction when the water addition ratio is low.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressure reduction is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control to make the heating power smaller, that is, weaker, than the set reference value of the heating power (step S1212 in fig. 7). The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, by reducing the heating power, the evaporation of the water in the boiler 5 can be suppressed, and the water amount in the boiler 5 can be brought close to the water amount in the reference state. This can prevent the cooking state of the material to be cooked from deviating from the reference state.

Specifically, the control unit 20 controls the heating power of the pan 5 by the heating coil 11 through the inverter circuit 12, as in the heating power control at the time of pressurization. After the completion of the pressure reduction, the control unit 20 controls the energization ratio of the heating coil 11 to change the heating power D0 from the reference state to heating power D1 that is weaker than heating power D0, as shown in fig. 19. Specifically, the control unit 20 increases the ratio of the current supplied to the side heating coils 11b to decrease the ratio of the current supplied to the bottom heating coils 11a, thereby reducing the heating power compared to the heating power in the reference state.

When the control unit 20 determines that the gradient of the pressure change curve during pressure reduction is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs control to make the heating power larger than the set heating power reference value, that is, to make the heating power stronger (step S1224 of fig. 7). The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. Therefore, the amount of water in the boiler 5 can be made closer to the reference amount of water by increasing the amount of water evaporated in the boiler 5 by increasing the heating power. This can prevent the cooking state of the material to be cooked from deviating from the reference state.

Specifically, the control unit 20 controls the energization ratio of the heating coil 11 by the inverter circuit 12 in the same manner as the heating power control at the time of pressurization, and after the pressure reduction is completed, changes the heating power D0 from the reference state to the heating power D2 stronger than the heating power D0 as shown in fig. 19. Specifically, the control unit 20 increases the ratio of the current supplied to the bottom surface heating coil 11a, and decreases the ratio of the current supplied to the side heating coil 11b, thereby making the heating power stronger than the heating power in the reference state.

[ example 7]

In addition to the above control, the following parameter adjustment control may be performed to bring the cooking state of the object to be cooked by the rice cooker 1 close to the reference cooking state, thereby improving the taste. Fig. 20 is a diagram illustrating a water adding ratio and a control method of the rice cooker of the embodiment.

As shown in fig. 20, in the rice cooker 1 of the present embodiment, (a) pressurization and depressurization, (B) heating power, (C) a rice cooking process, and (D) steam control can be performed according to the ratio of water addition in the pot 5.

The pressurization and depressurization shown in (a) can be adjusted in at least one of the pressurization width, the pressurization time (or pressurization start time), the depressurization time (or depressurization end time), and the pressure adjustment time (time during which pressurization and depressurization are performed).

The pressurization width is adjusted to be large when the water addition ratio is low, and to be small when the water addition ratio is high. The pressurization timing is adjusted earlier when the water addition ratio is low and later when the water addition ratio is high. The pressure reduction timing is adjusted later when the water addition ratio is low, and earlier when the water addition ratio is high. The pressure-adjusting time (time for performing pressurization and depressurization) is adjusted to be longer when the water addition ratio is low, and to be shorter when the water addition ratio is high.

The heating power shown in (B) can be adjusted in the ratio of the energization of the side heating coil 11B as the outer coil and the energization of the bottom heating coil 11a as the inner coil.

When the water addition ratio is low, the energization ratio of the side heating coil 11b and the bottom heating coil 11a is increased, and the energization ratio of the bottom heating coil 11a as the inner coil is decreased. This can reduce the heating power. When the water addition ratio is high, the energization ratio of the bottom heating coil 11a as the inner coil is increased, and the energization ratio of the side heating coil 11b as the outer coil is decreased. This can increase the heating power.

In the cooking step (C), at least one of the temperature maintaining time after the completion of cooking, the total time in the steaming step, the pressing time and the pressing width in the steaming step, and the cooking temperature can be adjusted.

The temperature maintaining time after the boil-off was adjusted to be longer when the water addition ratio was low, and to be shorter when the water addition ratio was high. The temperature for boil-off was adjusted to be high when the water addition ratio was low, and to be low when the water addition ratio was high.

The total time in the steaming step is adjusted to be longer when the water addition ratio is low, and to be shorter when the water addition ratio is high. The pressurization time in the steaming step is adjusted to be long when the water addition ratio is low, and to be short when the water addition ratio is high. The pressure range in the steaming step is adjusted to be large when the water addition ratio is low, and to be small when the water addition ratio is high.

As for the steam shown in (D), at least one of the steam temperature and the amount of water in the water tank, that is, the total amount of steam can be adjusted.

The steam temperature is adjusted to be low when the water addition ratio is low, and to be high when the water addition ratio is high. The total amount of steam is adjusted to be small when the water addition ratio is low, and to be large when the water addition ratio is high.

By adjusting at least one of these parameters according to the water addition ratio, the cooking state of the object to be cooked by the rice cooking device 1 can be brought close to the reference state, and the taste can be improved.

As described above, the rice cooker 1 of the present embodiment includes the pan 5, the bottom heating coil 11a and the side heating coil 11b (an example of a heating unit), the pressure adjusting unit 13, the pressure detecting unit 22, and the control unit 20. The pot 5 accommodates the material to be cooked. The bottom surface heating coil 11a and the side surface heating coil 11b heat the pan 5. The pressure adjusting unit 13 has a steam port 4a for releasing gas from the interior of the boiler 5, and adjusts the pressure in the boiler 5 by adjusting the open/close state of the steam port 4 a. The steam port 4a constitutes a pressure valve. The pressure detecting unit 22 detects the pressure in the pot 5. The control unit 20 controls the bottom heating coil 11a, the side heating coil 11b, and the pressure adjustment unit 13 to perform the cooking process.

The control unit 29 changes the control of at least one of the bottom heating coil 11a, the side heating coil 11b, and the pressure adjustment unit 13 between the 1 st state and the 2 nd state in which the pressure change modes are different from each other. For example, the 1 st state is a case where the pressure change is steeper than a certain reference state. For example, the 2 nd state is a case where the pressure change is smoother than a certain reference state.

Here, there is a correlation between the manner of pressure change and the water addition ratio of the object to be cooked. That is, if the pressure is varied in different ways, the ratio of water added to the material to be cooked is different. Therefore, in the present embodiment, when the pressure change mode is different, the variation in the cooking state of the object to be cooked in each step is suppressed by changing the control of at least one of the temperature and the pressure, and the taste of the object to be cooked is improved.

More specifically, the rice cooker 1 according to embodiment 1 can grasp the water addition ratio of the contents during cooking by changing the pressure in the pot 5. Therefore, the rice cooker 1 can adjust at least one of the pressure in the pot 5 during cooking, the pressure increase width, the start time of the pressure increase and pressure decrease, the heating power, the temperature, and the like, according to the water addition ratio. Thus, in each step of the cooking step, the cooking operation of the rice cooking device can be controlled with high accuracy so that the cooking state of the object to be cooked approaches the cooking state at the time of cooking according to the pressure, the pressure-increasing width, the start time of the pressure increase and pressure decrease, the heating power, the temperature, and the like set in the reference state in which the object to be cooked and the water are in an appropriate ratio. Therefore, variation in the cooking state of the cooked object in each step can be suppressed, and the taste of the cooked object can be improved.

Further, since the water addition ratio during boiling can be estimated, when the water addition ratio is high, the control unit 20 controls at least one of the pressure adjustment unit 13 and the heating coil 11, thereby suppressing the flooding.

(embodiment mode 2)

In the above embodiment 1, the control unit is configured to change the control of at least one of the pressure and the temperature in accordance with the manner of the pressure change in the pan. On the other hand, embodiment 2 will be described with a focus on the following configuration: the control part changes the pressurizing time for applying pressure to the cooker according to the pressure change mode in the cooker. Since the mechanical structure and the electrical structure of the rice cooker 1 are substantially the same as those of embodiment 1, the description of the overlapping portions will be omitted.

Specifically, for example, in the boiling step, when the gradient of the pressure change curve based on the detection result of the pressure detecting unit 22 is gentler than the gradient of the reference curve, the control unit 20 determines that the water addition ratio is high, and controls the pressure adjusting unit 13 so as to shorten the pressurizing time. The adjustment parameters such as pressure and time at this time may be adjusted by a preset correction value. When the gradient of the pressure change curve based on the detection result of the pressure detecting unit 22 is steeper than the gradient of the reference curve, the control unit 20 determines that the water addition ratio is low, and controls the pressure adjusting unit 13 so as to extend the pressurizing time. The adjustment parameters such as pressure and time at this time may be adjusted by a preset correction value.

Here, in the case of performing control using the difference between the watering ratio corresponding to the pressure change curve based on the detection result of the pressure detecting unit 22 and the watering ratio corresponding to the reference curve, the control unit 20 may correct at least one of the adjustment parameters of the pressure, the time, and the like based on the reference value stored in the memory 20a when the detected difference is larger than a preset set value. When the adjustment parameter is corrected based on the reference value, the control unit 20 may determine a weighted correction value based on the difference, and may change the adjustment parameter based on the reference value using the correction value.

The rice cooking operation in embodiment 2 is the same as in embodiment 1. As shown in fig. 4, the cooking operation is performed in the order of the boiling step (step S10), the high temperature maintaining step (step S20), and the steaming step (step S30). The boiling step of the rice cooker of embodiment 2 is the same as that of embodiment 1. As shown in fig. 5A and 5B, in the boiling process, after the preheating and the preliminary heating are performed, the 1 st pressurizing and heating (step S11), the 1 st depressurizing (step S12), the 2 nd pressurizing and depressurizing (step S13), the 3 rd pressurizing and depressurizing (step S14), the 4 th pressurizing and depressurizing (step S15), and the boil-off (step S16) processes are performed.

Fig. 21 is a flowchart showing the 1 st pressurizing process of the rice cooker of embodiment 2. Fig. 22 is a flowchart illustrating the 1 st depressurization step of the rice cooker of embodiment 2.

As shown in fig. 21, in the 1 st pressurizing step, first, detection of a pressurizing gradient is started (step S1101A). In the detection of the pressurization gradient, the time after the start of the 1 st pressurization is measured by the time measuring unit 24, and the pressure in the pot 5 is detected by the pressure detecting unit 22. Then, the measured time and the detected pressure are stored in the memory 20 a. This detection is performed a predetermined number of times, for example, every 0.2s from the start of the 1 st pressurization, and the relationship between time and pressure is stored in the memory 20a as a pressure change curve. That is, the pressure change curve represents the change in pressure with respect to time.

Next, the control unit 20 compares the detected pressure change curve during pressurization with a preset reference curve during pressurization (step S1102A). Then, if it is determined that the detected pressure change curve at the time of pressurization is steeper than the reference curve, that is, the pressure does not rise gently from the reference curve (no in step S1102A), the control unit 20 determines that the water addition ratio is low (step S1110A). The control unit 20 sets the absolute value of the difference between the detected pressure change curve during pressurization and the reference curve as y.

The control unit 20 determines whether y is larger than a preset set value, and performs a cooking process by correcting adjustment parameters of the pressurization width and the pressurization time based on the reference value when y is larger than the set value. When y is smaller than the set value, the rice cooking process is performed without changing the adjustment parameter based on the reference value.

Next, the control unit 20 performs the 1 st pressurization width adjustment (step S1114A). When y is larger than the set value a0 (yes in step S1114A), the control unit 20 performs control to increase the pressurization width (step S1115A). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients a0 and y as a correction value (that is, the correction value is the correction pressurization width, i.e., the reference × a0 × y), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient a0 is a preset value (positive value). When y is equal to or less than the set value a0 (no in step S1114A), the control unit 20 does not change the pressurization width based on the preset reference value of the pressurization width (step S1116A).

Next, the control unit 20 performs the pressurization time adjustment for the 1 st time (step S1117A). The pressurization time is a time from when the pressure starts to increase to when the pressure starts to decrease. If y is greater than the set value B0 (yes in step S1117A), the control unit 20 performs control to shorten the pressure maintaining time (step S1118A). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the pressurization time by the coefficients b0 and y as a correction value (that is, the correction value is the correction time of the pressurization time is the reference × b0 × y), and adds the correction time of the pressurization time to the reference value of the pressurization time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization time is a time obtained by adding the correction time for starting pressurization. The coefficient b0 is a preset value (positive value). When y is equal to or less than the set value B0 (no in step S1117A), the control unit 20 does not change the pressurizing time based on the preset reference value of the pressurizing time (step S1119A).

When determining that the pressure of the detected pressure change curve during pressurization has increased more gradually than the pressure of the reference curve (yes in step S1102A), the control unit 20 determines that the water addition ratio is high (step S1120A). The control unit 20 sets the absolute value of the difference between the detected pressure change curve during pressurization and the reference curve as x.

The control unit 20 determines whether x is larger than a preset set value, and performs a cooking process by correcting adjustment parameters of the pressurization width and the pressurization time based on the reference value when x is larger than the set value. When x is smaller than the set value, the rice cooking process is performed without changing the adjustment parameter based on the reference value.

Next, the control unit 20 performs the pressurization width adjustment for the 1 st time (step S1124A). If x is greater than the set value AA0 (yes in step S1124A), controller 20 performs control to decrease the pressurization amount (step S1125A). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients aa0 and x as a correction value (that is, the correction value is the reference × aa0 × x)), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient aa0 is a preset value (negative value). If x is equal to or less than the set value AA0 (no in step S1124A), the control unit 20 does not change the pressurization width based on the preset reference value of the pressurization width (step S1126A).

Next, the control unit 20 performs the pressurization time adjustment for the 1 st time (step S1127A). The pressurization time is a time from when the pressure starts to increase to when the pressure starts to decrease. If x is greater than the set value BB0 (yes in step S1127A), the control unit 20 performs control to shorten the time for maintaining the pressure (step S1128A). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the pressurization time by the coefficients bb0 and x as a correction value (that is, the correction value is the correction time of the pressurization time equal to the reference × bb0 × x), and adds the correction time of the pressurization time to the reference value of the pressurization time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization time is a time obtained by adding the correction time for starting pressurization. The coefficient bb0 is a predetermined value (negative value). If x is equal to or less than the set value BB0 (no in step S1127A), the control unit 20 does not change the pressurizing time based on the preset reference value of the pressurizing time (step S1129A).

As shown in fig. 22, in the 1 st decompression step, first, detection of a decompression gradient is started (step S1201A). In the detection of the pressure reduction gradient, the time after the start of the 1 st pressure reduction is measured by the time measuring unit 24, and the pressure in the pot 5 is detected by the pressure detecting unit 22. Then, the measured time and the detected pressure are stored in the memory 20 a. This detection is performed a predetermined number of times, for example, every 0.2s from the start of the 1 st decompression, and the relationship between time and pressure is stored in the memory 20a as a pressure change curve.

Next, the control unit 20 compares the detected pressure change curve at the time of pressure reduction with a preset reference curve at the time of pressure reduction (step S1202A). Then, if it is determined that the pressure change curve at the time of the detected pressure reduction is steeper than the reference curve, that is, the pressure does not decrease more gently than the reference curve (no in step S1202A), the control unit 20 determines that the water addition ratio is low (step S1210A). The control unit 20 sets the absolute value of the difference between the detected pressure change curve at the time of pressure reduction and the reference curve to Y.

When determining that the pressure of the pressure change curve at the time of the detected pressure reduction has decreased more gently than the pressure of the reference curve (yes in step S1202A), the control unit 20 determines that the water addition ratio is high (step S1220A). The control unit 20 sets the absolute value of the difference between the detected pressure change curve at the time of pressure reduction and the reference curve to X. In embodiment 2, regardless of the magnitude of the absolute values X and Y, the pressure width and the pressure reduction time in the 1 st pressure reduction step may not be adjusted, and the pressure reduction step may be completed in the same manner as in the reference state. The absolute values X and Y are used in the 2 nd pressure increasing and decreasing process.

Fig. 23 is a flowchart showing the 2 nd pressurizing and depressurizing step of the rice cooker of the present embodiment. In the pressure increasing and reducing step after the 2 nd time, the pressure increasing time and the pressure increasing width are adjusted according to the water adding ratio determined in the pressure reducing step of the 1 st time.

If the water addition ratio is low (step S1310A), the 2 nd pressurization width adjustment is performed (step S1314A). When the absolute value Y is larger than the set value C0 (yes in step S1314A), the control unit 20 performs control to increase the pressurization width (step S1315A). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients c0 and Y as a correction value (that is, the correction value is the correction pressurization width × c0 × Y), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient c0 is a preset value (positive value). When Y is equal to or less than the set value C0 (no in step S1314A), the control unit 20 does not change the pressurization width based on the preset reference value of the pressurization width (step S1316A).

Next, the control unit 20 performs the 2 nd pressurization time adjustment (step S1317A). When Y is larger than the set value D0 (yes in step S1317A), the controller 20 performs control to extend the pressurization time (step S1318A). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the pressurization time by the coefficients d0 and Y as a correction value (that is, the correction value is the pressurization correction time equal to the reference × d0 × Y), and adds the pressurization correction time to the reference value of the pressurization time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization time is a time obtained by adding the correction time for pressurization. The coefficient d0 is a preset value (positive value). When Y is equal to or less than the set value D0 (no in step S1317A), the control unit 20 does not change the pressurization time based on the preset reference value of the pressurization time (step S1319A).

When the water addition ratio is high (step S1320A), the controller 20 performs the 2 nd pressurization width adjustment (step S1321A). When X is larger than the set value CC0 (yes in step S1321A), the controller 20 performs control to decrease the pressurization width (step S1322A). Specifically, the control unit 20 sets the pressurization width obtained by multiplying the reference value of the pressurization width by the coefficients cc0 and X as a correction value (that is, the correction value is the correction pressurization width × cc0 × X), and adds the correction pressurization width to the reference value of the pressurization width. Then, the control unit 20 controls the pressure adjustment unit 13 so that the pressurization width is the pressurization width to which the corrected pressurization width is added. The coefficient cc1 is a predetermined value (negative value). When X is equal to or less than the set value CC0 (no in step S1321A), the control unit 20 does not change the pressure application range based on the preset reference value of the pressure application range (step S1323A).

Next, the control unit 20 performs the 2 nd pressurization time adjustment (step S1324A). When X is larger than the set value DD0 (yes in step S1324A), the controller 20 performs control to shorten the pressurization time (step S1325A). Specifically, the control unit 20 sets a time obtained by multiplying the reference value of the pressurization time by the coefficients dd0 and X as a correction value (that is, the correction value is the pressurization correction time equal to the reference × dd0 × X), and adds the pressurization correction time to the reference value of the pressurization time. Then, the control unit 20 changes the setting of the time measuring unit 24 so that the pressurization time is a time obtained by adding the correction time for pressurization. The coefficient dd0 is a predetermined value (negative value). When X is equal to or less than the set value DD0 (no in step S1324A), the control unit 20 does not change the pressurization time based on the preset reference value of the pressurization time (step S1326A).

As described above, according to the rice cooker 1 of the present embodiment, since the water addition ratio of the contents during cooking can be grasped by being placed in the pot 5, the pressurization time in the pot 5 during cooking can be adjusted according to the water addition ratio. Further, the adjustment of the pressurization width may be performed in addition to the adjustment of the pressurization time, or may be performed instead of the adjustment of the pressurization time. Thus, the rice cooking operation of the rice cooking device can be controlled with high accuracy so that the cooking state of the object to be cooked approaches the cooking state at the time of cooking according to the pressurization width and the pressurization time set in the reference state in which the ratio of the object to be cooked to water is appropriate. Therefore, variation in the cooking state of the cooked object in each step can be suppressed, and the taste of the cooked object can be improved.

A specific example of control corresponding to a pressure change curve at the time of pressure reduction is shown below.

[ example 8]

As example 8, control in which the pressurization time is changed in accordance with the water addition ratio at the time of depressurization will be described.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressure reduction is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control to make the 2 nd pressurizing time longer than the set 2 nd pressurizing time. The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, by setting the pressing time longer than the reference state, the viscosity and the elastic force of the pressurized material can be increased, and the cooked state of the material in the pot 5 after completion of the pressure reduction can be brought closer to the cooked state of the material in the reference state.

Specifically, in fig. 24, the pressurization is performed for a time T0 in the case of the reference state shown by the straight line M1, but as shown by the straight line L1, the pressurization is performed for a time T1 longer than the time T0 in the case of the reference state in the case of a low water addition ratio.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressure reduction is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs control so that the 2 nd pressurization time is shorter than the set 2 nd pressurization time. The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. Therefore, by setting the pressing time shorter than the pressing time in the reference state, the viscosity and hardness of the pressurized material can be reduced, and the cooked state of the material in the pot 5 after completion of the pressurization and depressurization can be brought close to the cooked state of the material in the reference state.

Specifically, in fig. 24, the pressurization is performed for a time T0 in the case of the reference state shown by the straight line M1, but as shown by the straight line L1, the pressurization is performed for a time T2 shorter than the time T0 in the case of the reference state in the case of a high water addition rate. The control unit 20 may determine whether or not to perform the next pressure increase or decrease every time the pressure increase or decrease is completed.

[ example 9]

As example 9, a control for changing the pressurization width in accordance with the water addition ratio at the time of depressurization will be described.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressure reduction is steeper than the gradient of the reference curve, that is, when the water addition ratio is low, the control unit 20 performs control to make the 2 nd pressurizing width larger than the set 2 nd pressurizing width. The case where the water addition ratio is low means a state where the amount of water in the boiler 5 is small. Therefore, by increasing the pressure application range to be larger than the pressure application range in the reference state, the viscosity and the elastic force of the pressurized material to be cooked can be increased, and the cooked state of the material to be cooked in the pot 5 after the completion of the pressure application can be brought closer to the cooked state of the material to be cooked in the reference state.

Specifically, in fig. 25, in the case of the reference state shown by the straight line M1, the pressure is increased by the pressure increase width of P0, but as shown by the straight line L1, in the case where the water addition ratio is low, the pressure of P2 is increased smaller than P0 in the case of the reference state. The control unit 20 may determine whether or not to perform the next pressure increase or decrease every time the pressure increase or decrease is completed.

When the control unit 20 determines that the gradient of the pressure change curve at the time of pressure reduction is gentler than the gradient of the reference curve, that is, when the water addition ratio is high, the control unit 20 performs control so that the 2 nd pressurization width is smaller than the set 2 nd pressurization width. The case where the ratio of water addition is high means a state where the amount of water in the boiler 5 is large. Therefore, by making the pressing width smaller than the pressing width in the reference state, the viscosity and hardness of the pressurized material can be reduced, and the cooked state of the material in the pot 5 after completion of the pressurization and depressurization can be made closer to the cooked state of the material in the reference state.

Specifically, in fig. 25, the pressurization width P0 is performed in the case of the reference state shown by the straight line M1, but as shown by the straight line H1, the pressurization width P2 smaller than the pressurization width P0 in the case of the reference state is performed in the case where the water addition ratio is low. The control unit 20 may determine whether or not to perform the next pressure increase or decrease every time the pressure increase or decrease is completed.

Although the rice cooker of the embodiment disclosed herein has been described above, the disclosure herein is not limited to the above embodiment.

For example, in embodiment 2, the configuration in which the pressurization time and the pressurization width are changed in accordance with the pressure change is exemplified, but only the pressurization time or only the pressurization width may be changed.

Further, for example, a plurality of reference curves for the pressurization gradient and the depressurization may be prepared in accordance with a desired state of the cooked object after cooking (for example, texture such as hardness, stickiness, and firmness, taste, and flavor). Further, setting values such as pressure, time, temperature, and the like in a plurality of steps may be prepared according to a desired state of the cooked object.

(other embodiments)

While the rice cooker of the embodiment disclosed herein has been described above, the disclosure herein is not limited to the above-described

embodiments

1 and 2.

For example, a plurality of reference curves for the pressurization and depressurization may be prepared in accordance with a desired state of the cooked object after cooking (for example, texture such as hardness, stickiness, and firmness, and taste). Further, setting values such as pressure, time, and temperature in a plurality of steps may be prepared according to a desired state of the cooked object after cooking.

In the above embodiment, at least one of the adjustment parameters such as the heating power, the pressure, and the time is changed based on the reference value when the differences X, Y, and Y are larger than the set values, and is not changed based on the reference value when the differences X, Y, and Y are smaller than the set values. Further, each reference value may be appropriately changed.

In

embodiments

1 and 2, the pressure increasing and reducing step after the 2 nd time may be performed only 1 time or a plurality of times depending on the water addition ratio.

In the steaming step, the temperature, timing, and duration of the steam injection from the steam unit may be controlled according to the water addition ratio.

In the

above embodiments

1 and 2, the rice cooker has the memory and the storage unit, but they may be 1 storage unit.

In

embodiments

1 and 2 described above, the rice cooker main body is configured to have two coils of the bottom heating coil and the side heating coil as the heating coils, but the number of the heating coils may be 1, or 3 or more. The position where the heating coil is disposed may be any position on the bottom surface side or the side surface side of the pan.

The values of pressure, temperature, and time shown in the above embodiments are examples, and may be changed as appropriate.

The numerical values, shapes, and materials used in the above embodiments are all exemplified for specifically explaining the disclosure herein, and the disclosure herein is not limited to the exemplified numerical values, shapes, and materials.

The disclosure herein also includes embodiments in which various modifications of the embodiments are made as would occur to those skilled in the art, and embodiments in which the structural elements and functions of the embodiments and the modifications are arbitrarily combined without departing from the scope of the subject disclosure.

Industrial applicability

The rice cooker disclosed herein is useful for an induction heating type rice cooker that heats by applying a high-frequency current to a heating coil, a heater type rice cooker that heats by an electric heater, and the like.

Claims

1. A rice cooker, comprising:

a pot for accommodating the material to be cooked;

a heating unit that heats the pan;

a pressure adjustment unit having a pressure valve for releasing gas from the cooker, the pressure adjustment unit adjusting the pressure in the cooker by adjusting the open/close state of the pressure valve;

a pressure detecting unit that detects the pressure in the pan; and

a control unit for controlling the heating unit and the pressure adjustment unit to perform a cooking process,

the control section changes control of at least one of the heating section and the pressure adjusting section between a1 st state and a 2 nd state in which modes of pressure change in the pan are different from each other,

said manner of said pressure variation corresponds to a gradient of a pressure variation curve in case the relation between time and said pressure in said pan is expressed as said pressure variation curve,

the rice cooker further has:

a time measuring unit for measuring the time; and

a storage unit that stores a relationship between the time measured by the time measuring unit and the pressure detected by the pressure detecting unit as the pressure change curve,

when the relation between the time and the pressure in the pot is expressed as a reference curve when the ratio of water added to the material to be cooked is a predetermined ratio,

the 1 st state is a state in which the gradient of the pressure change curve is steeper than that of the reference curve,

the 2 nd state is a state in which the gradient of the pressure change curve is gentler than the gradient of the reference curve,

the storage unit stores the reference curve,

the control unit compares the gradient of the pressure change curve with the gradient of the reference curve,

the control unit detects a difference between a water addition ratio corresponding to the pressure change curve and the predetermined water addition ratio corresponding to the reference curve, calculates a correction value corresponding to the difference, and changes the control of at least one of the heating unit and the pressure adjusting unit using the correction value.

2. The rice cooker of claim 1,

the control unit changes a pressurization time for applying the pressure to the pan between the 1 st state and the 2 nd state.

3. The rice cooker of claim 1,

the cooking step includes: a pressurizing step of applying pressure to the pot; and a pressure reduction step of reducing the pressure in the pan,

the mode of the pressure change corresponds to the gradient of the pressure change curve when the pressure in the pan rises in the pressurization process.

4. The rice cooker of claim 3,

the control unit changes the decompression start time in the decompression step between the 1 st state and the 2 nd state of the mode of the pressure change.

5. The rice cooker of claim 3,

the control unit changes the heating power of the heating unit between the 1 st state and the 2 nd state of the mode in which the pressure is changed.

6. The rice cooker of claim 3,

the control unit changes a pressurizing width when the pressure is increased in the pressurizing step between the 1 st state and the 2 nd state of the mode in which the pressure is changed.

7. The rice cooker of claim 3,

the control unit changes a start timing of another pressurizing step performed after the depressurizing step between the 1 st state and the 2 nd state of the mode of the pressure change.

8. The rice cooker of claim 3,

the control unit changes the number of times of each of the other pressurizing step and the other depressurizing step performed after the depressurizing step between the 1 st state and the 2 nd state of the mode in which the pressure changes.

9. The rice cooker of claim 3,

the control unit changes the temperature of the boil-off state between the 1 st state and the 2 nd state of the mode in which the pressure is changed.

10. The rice cooker of claim 1,

the mode of the pressure change corresponds to the gradient of the pressure change curve when the pressure in the pan is reduced in the depressurization step.

11. The rice cooker of claim 10,

the control unit changes a decompression completion time in the decompression step between the 1 st state and the 2 nd state of the mode of the pressure change.

12. The rice cooker of claim 10,

the control unit controls the heating unit to change the heating power of the heating unit between the 1 st state and the 2 nd state of the mode in which the pressure is changed.

13. The rice cooker of claim 10,

the control unit changes a pressurizing width at the time of the pressure increase in the pressurizing step performed after the depressurizing step between the 1 st state and the 2 nd state of the mode in which the pressure changes.

14. The rice cooker of claim 10,

the control unit changes a start timing of the pressurization step performed after the depressurization step between the 1 st state and the 2 nd state of the mode in which the pressure is changed.

15. The rice cooker of claim 10,

the control unit changes the number of times of the pressurizing step and the other depressurizing steps performed after the depressurizing step between the 1 st state and the 2 nd state of the mode in which the pressure changes.

16. The rice cooker of claim 10,