A cooking appliance

Abstract

A cooking appliance includes a pot body, a cover body, a bottom heating device, a side heating device and / or a bottom heating device, a top temperature sensor or a bottom temperature sensor, and a control device. An inner pot in the pot body is a non-coated inner pot. The control device is configured to execute a cooking program, the cooking program including a maintaining boiling phase and a braising phase. The maintaining boiling phase includes: controlling the bottom heating device to operate in a first heating cycle having a first duty cycle for a first time period, controlling the bottom heating device and / or the top heating device to operate in a second heating cycle having a second duty cycle after the first time period ends, ending the maintaining boiling phase and entering the braising phase when an increase in temperature detected by the top temperature sensor or the bottom temperature sensor in the second heating cycle exceeds a threshold. The braising phase includes controlling the bottom heating device to stop operating, and controlling the side heating device and / or the top heating device to operate.

Description

Technical Field

[0001] This application relates to the field of kitchen appliance technology, and more specifically to a cooking utensil. Background Technology

[0002] Currently, most rice cooker inner pots are coated, such as with polytetrafluoroethylene (PTFE), which gives them non-stick properties. However, as people become more health-conscious, some consumers are hesitant to use coated inner pots, but they also don't want to experience sticking when cooking with uncoated inner pots.

[0003] Therefore, a cooking appliance is needed to at least partially solve the above problems. Summary of the Invention

[0004] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] To at least partially solve the above problems, this application provides a cooking appliance, the cooking appliance comprising: A pot body, wherein the pot body is provided with an inner pot, wherein the inner pot is an uncoated inner pot; A lid that can be opened and closed is provided on the pot body. When the lid is closed on the pot body, a cooking space is formed between the lid and the inner pot. A bottom heating device is located below the inner pot; A side heating device and / or a top heating device, wherein the side heating device is disposed on the outer periphery of the side of the inner pot, and the top heating device is disposed on the top of the cooking space; A top temperature sensor or a bottom temperature sensor, wherein the top temperature sensor is used to monitor the top temperature of the inner pot, and the bottom temperature sensor is used to detect the bottom temperature of the inner pot; A control device electrically connected to the bottom heating device, the side heating device and / or the top heating device and the top temperature sensor or the bottom temperature sensor, the control device being configured to execute a cooking program including a boiling stage and a simmering stage. The boiling maintenance phase includes: During the first time period, the bottom heating device is controlled to operate in a first heating cycle, the first heating cycle having a first duty cycle. After the first time period ends, a second time period begins. During the second time period, the bottom heating device is controlled to operate in a second heating cycle, which has a second duty cycle. When the temperature T detected by the top temperature sensor 顶 Or the temperature T detected by the bottom temperature sensor 底 The increase in amplitude ΔT during the second heating cycle 顶 or △T 底 Exceeding the threshold △T 阈 When, or when the second time period ends, the boiling maintenance phase ends and the rice simmering phase begins; The rice-cooking stage includes: controlling the bottom heating device to stop working, and controlling the side heating device and / or the top heating device to operate.

[0006] According to the cooking appliance of this application, by aligning the end point of the boiling stage with the time point when the water boils dry, and stopping bottom heating after the water boils dry and switching to side heating and / or top heating for steaming rice, it can ensure that the rice is cooked and prevent the bottom of the pot from sticking to the pot due to prolonged overheating, thus achieving a non-stick effect when cooking rice in an uncoated inner pot.

[0007] Optionally, the first heating cycle is 30s~50s, the second heating cycle is 30s~50s, and the threshold is 2℃~6℃. According to this solution, the determination of the time point when the water boils dry is more accurate.

[0008] Optionally, the first time period is 5 min to 10 min, the second time period is 5 min to 10 min, and the average power of the bottom heating device in the first heating cycle is 30% to 50% of the rated power; The average power of the bottom heating device during the second heating cycle is 40% to 60% of its rated power. Based on this setting, the time required for determining whether the water has boiled dry is minimized, reducing the possibility of the bottom of the pot burning.

[0009] Optionally, the rice-cooking stage includes: During the third time period, the side heating device and / or the top heating device are controlled to operate in a third heating cycle, the third heating cycle having a third duty cycle; During the fourth time period, the side heating device and / or top heating device are controlled to operate in a fourth heating cycle, which has a fourth duty cycle. According to the above settings, the cooking time is extended, ensuring that the rice is cooked thoroughly by side heating.

[0010] Optionally, the third time period is 2 min to 5 min, and the average power of the side heating device and / or top heating device in the third heating cycle is 30% to 50% of the rated power; The fourth heating period is 5 to 9 minutes, and the average power of the side heating device and / or top heating device during the fourth heating cycle is 20% to 50% of the rated power. Based on the above settings, the rice is ensured to be cooked thoroughly while minimizing the cooking time.

[0011] Optionally, the cooking process further includes a heat preservation stage, and the rice simmering stage further includes: after the fourth time period ends, controlling the side heating device and / or the top heating device to stop working and continue for a fifth time period, after which the heat preservation stage begins, the fifth time period being 10 to 20 minutes. According to the above settings, the cooked rice is further ensured to be cooked properly.

[0012] Optionally, the cooking process further includes: The water absorption stage includes: controlling the bottom heating device to heat the inner pot and making the temperature detected by the top temperature sensor or the bottom temperature sensor reach the target water absorption temperature so that the food absorbs water, and ending the water absorption stage when the running time of the bottom heating device reaches a first preset time. The heating stage, which follows the water absorption stage, includes: controlling the bottom heating device to heat the inner pot with an average power greater than or equal to 80% of the rated power, determining the amount of rice based on the time it takes for the temperature detected by the top temperature sensor or the bottom temperature sensor to reach a first preset temperature, and ending the heating stage when the top temperature sensor or the bottom temperature sensor reaches a second preset temperature, wherein the second preset temperature is greater than the first preset temperature. The boiling determination stage, which occurs between the boiling maintenance stage and the heating stage, includes controlling the bottom heating device to heat the inner pot and determining whether the contents of the pot have boiled based on the temperature detected by the top temperature sensor or the bottom temperature sensor. This solution improves cooking results.

[0013] Optionally, the target water absorption temperature is 55℃~59℃, and the first preset time is 5min~15min. This ensures that the rice grains absorb water fully.

[0014] Optionally, the water absorption stage includes: When T 顶 or T 底 When the temperature is ≤50℃, the bottom heating device is controlled to operate in a fifth heating cycle, the fifth heating cycle having a fifth duty cycle, and the average power of the bottom heating device in the fifth heating cycle being greater than or equal to 80% of the rated power; When 50℃ < T 顶 or T 底When the temperature is ≤55℃, the bottom heating device is controlled to operate in the sixth heating cycle, the sixth heating cycle having a sixth duty cycle, and the average power of the bottom heating device in the sixth heating cycle is 30%~80% of the rated power; When 55℃ < T 顶 or T 底 When the temperature is below 59°C, the bottom heating device is controlled to operate in a seventh heating cycle, which has a sixth duty cycle. The average power of the bottom heating device during this seventh heating cycle is less than or equal to 30% of its rated power. This solution improves the water absorption effect of the rice grains.

[0015] Optionally, when the temperature T detected by the top temperature sensor 顶 Or the temperature T detected by the bottom temperature sensor 底 After the temperature first exceeds 55℃, if T 顶 or T 底 If the temperature is ≥59℃, the bottom heating device will stop working. 顶 or T 底 If the temperature is ≤55℃, the bottom heating device is controlled to heat at an average power of less than or equal to 30% of its rated power. According to this solution, maintaining water absorption at low power improves temperature stability, reduces the burden on the heating device, saves energy, and extends product lifespan.

[0016] Optionally, the first preset temperature is 60℃~80℃, and the second preset temperature is 75℃~85℃.

[0017] Optionally, the heating stage includes: The bottom heating device is controlled to operate in an eighth heating cycle, the eighth heating cycle having an eighth duty cycle, and the average power of the bottom heating device in the eighth heating cycle being greater than or equal to 80% of its rated power. When the temperature detected by the top or bottom temperature sensor reaches the first preset temperature, the bottom heating device is controlled to operate in a ninth heating cycle. This ninth heating cycle has a ninth duty cycle, and the average power of the bottom heating device during this ninth heating cycle is greater than or equal to 80% of its rated power. When the temperature detected by the top or bottom temperature sensor reaches the second preset temperature, the heating phase ends. According to this solution, the contents of the pot are heated to boiling as quickly as possible while simultaneously determining the amount of rice, thus shortening the cooking time.

[0018] Optionally, when the time it takes for the temperature detected by the top temperature sensor or the bottom temperature sensor to reach the first preset temperature is less than or equal to 7 minutes, it is determined to be a milligram quantity; When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches the first preset temperature for a time greater than 7 minutes and less than or equal to 13 minutes, it is determined to be medium rice quantity. When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches the first preset temperature for more than 13 minutes, it is determined to be the amount of rice. Specifically, the fourth time period corresponding to medium-sized rice is longer than the fourth time period corresponding to small-sized rice, and the fourth time period corresponding to large-sized rice is longer than the fourth time period corresponding to medium-sized rice. According to this solution, the rice quantity is first determined, and then the heating time of the side heating device and / or top heating device is automatically adjusted based on the rice quantity, maintaining consistent cooking results across multiple rice cooking sessions.

[0019] Optionally, the determination of the boiling stage includes: The bottom heating device is controlled to operate in a tenth heating cycle, the tenth heating cycle having a tenth duty cycle, and the average power of the bottom heating device in the tenth heating cycle being greater than or equal to 70% of its rated power. When the temperature detected by the top or bottom temperature sensor is greater than or equal to a third preset temperature, which is greater than the second preset temperature, it is determined that the contents of the pot have boiled. According to this solution, the determination of boiling is relatively accurate.

[0020] Optionally, the third preset temperature is 80℃~90℃; and / or the third preset temperature is 8℃~11℃ lower than the local boiling point. According to this solution, cooking at different altitudes is possible.

[0021] Optionally, the determination of the boiling stage includes: The bottom heating device is controlled to operate in a tenth heating cycle, the tenth heating cycle having a tenth duty cycle, and the average power of the bottom heating device in the tenth heating cycle being greater than or equal to 70% of its rated power. If the temperature detected by the top or bottom temperature sensor remains unchanged within 20 to 40 seconds, it is determined that the contents of the pot have boiled. Based on the above settings, the determination of boiling is relatively accurate. Attached Figure Description

[0022] The following figures are included as part of this application for understanding the invention. The figures illustrate embodiments of the invention and their descriptions, serving to explain the principles of the invention. In the figures: Figure 1 This is a schematic diagram of a cooking appliance according to one embodiment of the present application; Figure 2 This is a partial schematic diagram of the internal structure of the pot of a cooking appliance according to one embodiment of this application; Figure 3 This is a schematic flowchart of a cooking procedure according to one embodiment of this application; Figure 4 This is a time-series diagram of the temperature of various parts of a cooking appliance according to one embodiment of the present application during a specific process of cooking rice; Figure 5 For a cooking appliance according to one embodiment of this application and Figure 4 The temperature timing diagram corresponds to the heating power timing diagram; Figure 6 A cross-sectional schematic view of the inner pot of a cooking appliance according to one embodiment of this application; Figure 7 This is a cross-sectional schematic diagram of another embodiment of the inner pot of a cooking appliance according to one embodiment of this application. Detailed Implementation

[0023] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of the stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof.

[0025] The ordinal numbers such as “first” and “second” used in this application are merely identifiers and have no other meaning, such as a specific order. Furthermore, for example, the term “first component” does not imply the existence of a “second component,” and the term “second component” does not imply the existence of a “first component.” It should be noted that the terms “upper,” “lower,” “front,” “back,” “left,” “right,” “inner,” “outer,” and similar expressions used herein are for illustrative purposes only and are not intended to be limiting.

[0026] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings.

[0027] This application provides a cooking utensil 10, for reference... Figure 1The container includes a lid 13 and a pot body 11. The lid 13 has a shape that substantially corresponds to the pot body 11. The lid 13 is closable and can be opened and closed on the pot body 11. The lid 13 can be pivotally connected to the pot body 11, for example, via a pivot axis, and can pivot freely about the pivot axis between a closed position and an open position relative to the pot body 11 to facilitate closing and opening the pot body 11. The pot body 11 is provided with a lid-opening button 17, which automatically opens the lid 13 when pressed by the user.

[0028] The pot body 11 includes an inner pot 12 and has a cylindrical storage compartment. The inner pot 12 can be freely placed into or removed from the storage compartment for easy cleaning. The inner pot 12 is typically made of metal and has a circular opening on its upper surface for holding materials to be heated, such as rice or soup. Specifically, the inner pot 12 is an uncoated inner pot, for example, an uncoated stainless steel inner pot. The pot body 11 also has a middle plate with an opening corresponding to the storage compartment to allow the inner pot 12 to be inserted and removed.

[0029] refer to Figure 2 The cooker body 11 also includes a heat-insulating cover 21, within which the inner pot 12 is housed. In other words, the heat-insulating cover 21 forms the aforementioned storage section. The cooker body 11 includes a bottom heating device 19 for heating the inner pot 12. This bottom heating device 19 is located below the inner pot 12, specifically below the heat-insulating cover 21, and is primarily used for heating during the cooking process. The cooker body 11 also includes a bottom temperature sensor (not shown) for detecting the bottom temperature T of the inner pot 12. 底 .

[0030] The pot body 11 also includes a side heating device 20, which is disposed on the outer periphery of the side of the inner pot 12, such as... Figure 2 The side heating device 20 shown is disposed on the outer periphery of the heat preservation cover 21 and is used to heat and keep the side of the inner pot 12 warm. As one implementation, both the side heating device 20 and the bottom heating device 19 are preferably constructed as electric heating devices, for example, the bottom heating device 19 is constructed as a bottom electric heating plate and the side heating device 20 is constructed as a side electric heating tape.

[0031] The pot body 11 may also include a top heating device (not shown), which is disposed on the top of the inner pot 12. For example, the top heating device may be disposed on the lid 13, for heating the cooking cavity of the inner pot 12 from the top of the inner pot 12. As one implementation, the top heating device is preferably a far-infrared heating device.

[0032] It should be noted that in some embodiments, the pot body 11 may only include the bottom heating device 19 and the side heating device 20; in other embodiments, the pot body 11 may only include the bottom heating device 19 and the top heating device; in other embodiments, the pot body 11 may include the bottom heating device 19, the side heating device 20 and the top heating device.

[0033] It is worth mentioning that the aforementioned side heating device 20, top heating device, and bottom heating device 19 typically cannot have their power directly adjusted; they heat at their rated power after being powered on. When different heating powers are required, the heating duty cycle is typically used for adjustment. Specifically, the side heating device 20, top heating device, and bottom heating device 19 operate in a heating cycle mode. Within one heating cycle, they are powered on for a first time to heat, and then powered off for a second time to stop operation. The sum of the first and second times can be called a heating cycle, and the ratio of the first time to a heating cycle is called the heating duty cycle. It is easy to understand that the average power refers to the heating duty cycle multiplied by the rated power.

[0034] When the lid 13 is closed on the pot body 11, it covers the inner pot 12, forming a cooking space between them. The lid 13 includes a top cover 14, a lid liner (not shown), a panel 15, and a removable cover (not shown). The top cover 14 is located above the lid liner, the removable cover is located below the lid liner, and the panel 15 is located on the top cover 14. The panel 15 has operation buttons 16 for the user to set cooking parameters. The lid liner is the main component of the lid 13 of the cooking appliance 10, serving as a direct or indirect support for various devices and components mounted on the lid 13. The lid 13 typically also has a pot opening sealing ring, which can be made of, for example, rubber material, and is located between the lid 13 and the inner pot 12 to seal the cooking space when the lid 13 is closed. The lid 13 also has a micro-pressure component 18 for venting water vapor from the cooking space.

[0035] A top temperature sensor (not shown) may also be provided in the lid 13, which is used to monitor the temperature T at the top of the inner pot 12, or the cooking space. 顶 The temperature detected here is the temperature of the steam. When the temperature inside the pot is high, the temperature of the top of the inner pot 12 is closer to the temperature of the rice-water mixture than the temperature measured by contact with the outer wall of the pot bottom. Therefore, cooking conditions based on the temperature of the top of the inner pot 12 are more accurate when the temperature inside the pot is high. Specifically, the top temperature sensor can be set on the bottom side of the lid 13 or in the steam channel.

[0036] It is understood that the cooking appliance 10 according to this application can be a rice cooker, an electric pressure cooker or other cooking appliance 10, and the cooking appliance 10 can have various functions such as cooking porridge in addition to cooking rice.

[0037] The cooking appliance 10 also includes a control device connected to the bottom heating element 19, the side heating element 20, the top heating element, the bottom temperature sensor, and the top temperature sensor. The control device is configured to execute a cooking program when the user selects the rice cooking function. An example of a cooking program can be found here. Figure 3 It may include a water absorption stage, a heating stage, a boiling determination stage, a boiling maintenance stage, a rice simmering stage, and a heat preservation stage, executed sequentially. In other embodiments, the cooking process may also include a water absorption stage, a heating stage, a boiling determination stage, a boiling maintenance stage, a porridge cooking stage, and a heat preservation stage, executed sequentially.

[0038] Below, for reference Figure 3 , Figure 4 and Figure 5 The cooking procedure of cooking appliance 10 is described in detail. Figure 4 and Figure 5 The timing diagrams of actual temperature and heating power of the cooking appliance 10, which has a bottom heating device 19 and a side heating device 20, during the specific process of cooking rice are shown respectively.

[0039] When the user places the inner pot 12 containing ingredients such as rice and water into the cooker body 11 and closes the lid 30, they can select the rice cooking function to start cooking.

[0040] Preheating stage Before the water absorption stage, preparation can be carried out at the beginning of the cooking process. That is, no heating is carried out for a period of time after the cooking starts, such as 10 to 30 seconds, so that the temperature detected by the top or bottom temperature sensor tends to stabilize and obtain the initial temperature of the food before entering the water absorption stage.

[0041] Water absorption stage The water absorption stage includes controlling the bottom heating device 19 to heat the inner pot 12 until the temperature detected by the top temperature sensor or the bottom temperature sensor reaches the target water absorption temperature so that the food absorbs water. The water absorption stage ends when the bottom heating device 19 has been running for a first preset time. The target water absorption temperature is 55℃~59℃, and the first preset time is 5min~15min, preferably 10min.

[0042] During this stage, the bottom heating element 19 operates intermittently to maintain the food temperature (which can be reflected by the side and bottom temperatures of the inner pot 12) at a suitable water absorption temperature. More specifically, when the temperature T detected by the top temperature sensor... 顶Or the temperature T detected by the bottom temperature sensor 底 When the temperature is less than or equal to 50°C, the bottom heating device 19 operates in the fifth heating cycle, which has a fifth duty cycle. The average power of the bottom heating device 19 during the fifth heating cycle is greater than or equal to 80% of its rated power. When 50°C < T 顶 or T 底 When the temperature is ≤55℃, the bottom heating device 19 operates in the sixth heating cycle, which has a sixth duty cycle. The average power of the bottom heating device 19 during the sixth heating cycle is 30%~80% of its rated power. When 55℃ <T 顶 or T 底 When the temperature is <59℃, the bottom heating device 19 is controlled to operate in the seventh heating cycle, which has a sixth duty cycle. The average power of the bottom heating device 19 in the seventh heating cycle is less than or equal to 30% of the rated power.

[0043] Furthermore, when the temperature T detected by the top temperature sensor... 顶 Or the temperature T detected by the bottom temperature sensor 底 After the temperature first exceeds 55℃, if T 顶 or T 底 If the temperature is ≥59℃, the bottom heating device 19 will stop working. 顶 or T 底 If the temperature is ≤55℃, the bottom heating device 19 is controlled to heat at an average power of less than or equal to 30% of its rated power. This maintains water absorption at low power, improves temperature stability, reduces the burden on the heating device, saves energy, and extends product lifespan. Furthermore, due to the design of the water absorption stage described above, there is no need for additional preheating of the inner pot 12. Here, since the temperature inside the pot is low during the water absorption stage and the preparation stage before the water absorption stage, it is preferable to use the temperature detected by the bottom temperature sensor for control.

[0044] warming phase Following the water absorption stage, the heating phase involves the bottom heating device 19 operating at higher power to rapidly heat the food. During this phase, the control device analyzes the amount of food. Specifically, the heating phase includes controlling the bottom heating device 19 to heat the inner pot 12 at an average power greater than or equal to 80% of its rated power. The amount of rice is determined based on the time it takes for the temperature detected by the top or bottom temperature sensor to reach a first preset temperature. The heating phase ends when the temperature detected by the top or bottom temperature sensor reaches a second preset temperature, which is higher than the first preset temperature. The first preset temperature is 60℃~80℃, preferably 70℃. The second preset temperature is 75℃~85℃, preferably 80℃.

[0045] More specifically, the heating phase includes controlling the bottom heating device 19 to operate in an eighth heating cycle, the eighth heating cycle having an eighth duty cycle, and the average power of the bottom heating device 19 in the eighth heating cycle being greater than or equal to 80% of its rated power. When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches a first preset temperature, the bottom heating device 19 is controlled to operate in a ninth heating cycle, the ninth heating cycle having a ninth duty cycle, and the average power of the bottom heating device 19 in the ninth heating cycle being greater than or equal to 80% of its rated power. When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches a second preset temperature, the heating phase ends.

[0046] Simultaneously, during the heating phase, if the time it takes for the temperature detected by the top or bottom temperature sensor to reach the first preset temperature is less than or equal to 7 minutes, it is determined to be the amount of millet to be cooked. If the time it takes for the temperature detected by the top or bottom temperature sensor to reach the first preset temperature is greater than 7 minutes but less than or equal to 13 minutes, it is determined to be the amount of rice to be cooked. If the time it takes for the temperature detected by the top or bottom temperature sensor to reach the first preset temperature is greater than 13 minutes, it is determined to be the amount of whole rice to be cooked. Therefore, during the heating phase, high power is used for rapid heating to bring the contents of the pot to a boil as quickly as possible, while simultaneously determining the amount of rice, thus shortening the cooking time. After determining the amount of food, the bottom heating device 19 continues to operate to further increase the temperature of the food.

[0047] Furthermore, the average power of the bottom heating device 19 in the eighth heating cycle may be the same as or different from the average power in the ninth heating cycle. And these two values ​​may also be the same as or different from the average power of the bottom heating device 19 in the fifth heating cycle.

[0048] Determining the boiling stage The boiling stage is determined after the heating stage when the temperature at the top remains consistently and stably at a high level. The boiling stage involves controlling the bottom heating device 19 to heat the inner pot 12 and determining whether the contents of the pot have boiled based on the temperature detected by the top or bottom temperature sensor. Specifically, in the boiling stage, the bottom heating device 19 is first controlled to operate in a tenth heating cycle, which has a tenth duty cycle, and the average power of the bottom heating device 19 in the tenth heating cycle is greater than or equal to 70% of its rated power.

[0049] When the temperature detected by the top or bottom temperature sensor is greater than or equal to a third preset temperature, which is higher than the second preset temperature, it is determined that the contents of the pot have boiled. The third preset temperature is 80℃~90℃. In an optional embodiment, the third preset temperature is 8℃~11℃ lower than the local boiling point. The control device stores a table of data on the altitude of the cooking appliance and the third preset temperature, allowing the control device to automatically determine the value of the third preset temperature based on the current location.

[0050] Alternatively, if the temperature detected by the top or bottom temperature sensor remains unchanged for 20-40 seconds, it is determined that the contents of the pot have boiled. Either of these two conditions is sufficient to determine boiling. During the heating, boiling determination, and boiling maintenance phases, the temperature inside the pot is relatively high; therefore, the temperature detected by the top temperature sensor is preferred for control.

[0051] Maintaining boiling phase Once boiling is determined, a boiling maintenance phase begins. During this phase, the food, containing free moisture, remains in a boiling state, thus maintaining a relatively constant temperature. As one implementation, this boiling maintenance phase includes controlling the bottom heating device 19 to operate for a first heating cycle within a first time period. This first heating cycle has a first duty cycle. The first heating cycle is 30s to 50s, preferably 45s. The first time period is 5min to 10min, and the average power of the bottom heating device 19 during the first heating cycle is 30% to 50% of its rated power, preferably 40% of the rated power. Taking a 45s first heating cycle as an example, the device is powered on for 18s and then powered off for 27s; the average power during this first heating cycle is 40% of the rated power.

[0052] The boiling maintenance phase also includes entering a second phase after the first phase ends, during which the bottom heating device 19 is controlled to operate in a second heating cycle with a second duty cycle. The second heating cycle is 30s to 50s, preferably 45s. The average power of the bottom heating device 19 during the second heating cycle is 40% to 60% of its rated power, preferably 50% of its rated power.

[0053] In the second time period, when the temperature T detected by the top temperature sensor... 顶 Or the temperature T detected by the bottom temperature sensor 底 The increase in amplitude ΔT during a second heating cycle 顶 or △T 底 Exceeding threshold T 阈 At this point, the boiling maintenance phase ends and the rice simmering phase begins. Threshold T 阈The temperature is 2℃ to 6℃, preferably 3℃. Alternatively, at the end of the second period, the boiling maintenance phase ends and the rice simmering phase begins. The second period is 5 min to 10 min, preferably 7 min.

[0054] There are two conditions for determining the end of the boiling phase and the start of the simmering phase, and these two conditions are OR-related. Below, we assume the second heating cycle is 45 seconds and the threshold T... 阈 Taking a temperature of 3℃ as an example, and a second time period of 7 minutes as an example, a detailed description will be provided. During the second time period, when the temperature T detected by the top temperature sensor... 顶 Or the temperature T detected by the bottom temperature sensor 底 The increase in magnitude ΔT within 45 seconds 顶 or △T 底 If the temperature exceeds 3°C, the boiling phase ends and the rice simmering phase begins. If, during the second time period, the temperature T detected by the top temperature sensor... 顶 Or the temperature T detected by the bottom temperature sensor 底 The increase in magnitude ΔT within 45 seconds 顶 or △T 底 If the temperature does not exceed 3℃, the boiling stage will end and the rice simmering stage will begin when the second period of 7 minutes ends.

[0055] Rice cooking stage The rice-cooking stage includes: stopping the bottom heating device 19 and operating the side heating device 20 and / or the top heating device. Figure 5 It is clearly visible that the bottom heating device 19 only operates before the rice-cooking stage. During the entire rice-cooking stage, the bottom heating device 19 does not operate. The side heating device 20 only operates during the third and fourth time periods. Of course, to improve heating efficiency, the side heating device 20 can also operate before the rice-cooking stage.

[0056] According to the cooking appliance 10 of this application, by aligning the end point of the boiling stage with the time point when the water boils dry, and stopping bottom heating after the water boils dry and switching to side heating and / or top heating for steaming rice, it can ensure that the rice is cooked and prevent the bottom of the pot from sticking to the pot due to prolonged overheating, thus achieving a non-stick effect for cooking rice in the uncoated inner pot 12.

[0057] For the uncoated inner pot 12, if the bottom temperature is too high during the boiling stage, for example, if the bottom temperature exceeds 105°C for a period of time, sticking will occur. If the bottom temperature exceeds 135°C, the rice will become burnt. The higher the temperature and the longer it is maintained, the more severe the burning will be. This application, through the aforementioned control program, precisely judges the time when the water boils away at the end of the boiling stage and switches the bottom heating to side heating and / or top heating. This ensures that the rice is fully cooked while preventing the bottom temperature from becoming too high, and at the same time, the water film produced at the bottom of the pot prevents the rice from sticking.

[0058] More specifically, during cooking, rice releases starch into the water. A large amount of starch, under the influence of gravity, settles at the bottom, while a smaller amount adheres to the side walls of the inner pot. Therefore, the inner surface of the inner pot 12 exhibits a starch distribution pattern: less starch on the sides and more on the bottom, with the amount of starch gradually increasing from the sides to the bottom. Areas with higher starch distribution are also more prone to sticking. Generally speaking, as... Figure 6 As shown, based on the amount of starch adhering to the inner surface of the inner pot wall of the inner pot 12, the inner pot wall of the inner pot 12 can be divided into the following inner pot areas: The non-starch adhesion zone is a region where starch can move freely and its position can be changed by gravity. Since starch hardly adheres to the non-starch adhesion zone, sticking to the pot is almost non-existent. This region can also be called the third zone 24 of the inner pot. A small amount of starch adheres to the area where the movement of starch is hindered by the supporting force and friction of the inner surface of the inner pot 12, but gravity can still change the position of the starch. This area is a slightly sticky area and can also be called the second area 23 of the inner pot. The starch sedimentation zone is a region where starch movement is hindered by the supporting force and friction of the inner surface of the inner pot 12, and gravity can no longer change the position of the starch. This is a region of severe sticking to the pot, and this region can also be called the first zone 22 of the inner pot.

[0059] In this application, as Figure 6 As shown, the inner pot first region 22, inner pot second region 23 and inner pot third region 24 are divided according to the following method: In the cross section of the inner pot 12 passing through the axis PA (the cross section is in a vertical plane), the tangent of any point on the inner surface of the inner pot 12 has a first angle with the horizontal line on one side of the outer surface of the inner pot 12 and above the horizontal line. The portion with the first angle less than or equal to 31 degrees forms the inner pot first region 22, the portion with the first angle greater than 31 degrees and less than 90 degrees forms the inner pot second region 23, and the portion with the first angle greater than or equal to 90 degrees forms the inner pot third region 24.

[0060] For example, the tangent LA at point A on the inner surface of the bottom of the inner pot 12 intersects the horizontal line LH, and the two lines form a first angle α on one side of the outer surface of the inner pot 12 and above the horizontal line LH. The angle α is less than 31 degrees, so the inner pot area at point A is the first inner pot area 22. The tangent LB at point B on the inner surface of the side of the inner pot 12 intersects the horizontal line LH, and the two lines form a first angle β on one side of the outer surface of the inner pot 12 and above the horizontal line LH. The angle β is greater than 31 degrees and less than 90 degrees, so the inner pot area at point B is the second inner pot area 23. The tangent LC at point C on the inner surface of the upper part of the inner pot 12 intersects the horizontal line LH, and the two lines form a first angle γ on one side of the outer surface of the inner pot 12 and above the horizontal line LH. The angle γ is greater than 90 degrees, so the inner pot area at point C is the third inner pot area 24.

[0061] The above scheme is an illustrative representation of the inner pot's partitioning method. The partitioning of the inner pot is primarily based on the different amounts of starch adhesive that can adhere to different areas. Generally speaking, the further down the pot, the more severe the sticking. The first inner pot region 22 is located at the bottom, forming the bottom wall of the inner pot 12, also called the inner pot bottom 22 (inner pot bottom wall). Regardless of the shape of the inner pot, it will have a first inner pot region 22. The second inner pot region 23 and the third inner pot region 24 provide the side walls of the inner pot 12, also collectively referred to as the inner pot side 25 (inner pot side wall). The inner pot 12 has at least one of the second inner pot region 23 and the third inner pot region 24. The inner pot side 25 is located above the inner pot bottom 22.

[0062] exist Figure 7 In the example shown, the generatrix of the inner pot 12 wall is generally composed of multiple straight line segments. The first included angle of points on the inner surface of the inner pot 12 does not change continuously. Therefore, the horizontal line extending 2cm upwards from the lowest point of the inner surface of the inner pot 12 is defined as the bottom boundary line LD. The inner pot wall not higher than the bottom boundary line LD is the bottom 22 of the inner pot, and the inner pot wall higher than the bottom boundary line LD is the side 25 of the inner pot. That is, the portion with a height difference of no more than 2cm from the lowest point of the inner surface of the inner pot 12 forms the bottom 22 of the inner pot, and the remaining portion is the side 25 of the inner pot. In other words, the portion always located at the very bottom is the starch sedimentation zone.

[0063] At the bottom 22 of the inner pot, the movement of starch is hindered by the supporting force and friction of the inner surface of the inner pot 12. Gravity can no longer change the position of the starch, making this a heavily sticky area. According to this application, by controlling the temperature of the bottom 22 of the inner pot when the starch adhesive is about to solidify, the starch adhesive at the bottom can be prevented from solidifying and sticking to the pot. Understandably, after the boiling process, the bottom temperature can also be controlled by reducing the bottom power or using a low-power bottom heating method.

[0064] According to this application, when the ingredients are fully boiled during the boiling stage, and it is difficult to cook the rice in the middle and upper layers by relying on heat convection formed by bottom heating during the simmering stage, side heating and / or top heating are activated. The side heating device 20 and / or top heating device prevent starch from solidifying at the bottom 22 of the inner pot, and also provide a higher temperature to ensure the ingredients receive sufficient heat to ensure the rice is cooked and its aroma is enhanced. In other words, by carefully controlling the timing of switching between bottom heating and side heating and / or top heating, the rice can be cooked evenly, and the rice at the bottom 22 of the inner pot can be prevented from sticking.

[0065] During the rice-cooking stage, firstly, in the third time period, the side heating device 20 and / or the top heating device operate in a third heating cycle, which has a third duty cycle. The third time period is 2 to 5 minutes, preferably 3 minutes. The average power of the side heating device 20 and / or the top heating device during the third heating cycle is 30% to 50% of its rated power, preferably 40% of its rated power.

[0066] After the third heating period ends, during the fourth heating period, the side heating device 20 and / or the top heating device operate in a fourth heating cycle, which has a fourth duty cycle. The average power of the side heating device 20 and / or the top heating device during the fourth heating cycle is 20% to 50% of its rated power, preferably 30%. The fourth heating period lasts from 5 to 9 minutes. Here, the fourth heating period can vary depending on the amount of rice; the more rice, the longer the fourth heating period. For example, if the rice quantities are millet, medium, and large, the fourth heating period for medium rice is longer than that for millet, and the fourth heating period for large rice is longer than that for medium rice. As an example, the fourth heating period is 5 minutes when cooking millet, 7 minutes when cooking medium rice, and 9 minutes when cooking large rice. This application automatically adjusts the heating time of the side and / or top heating devices according to the amount of rice, maintaining consistent cooking results across multiple cooking sessions. Ordinary rice cookers have a fixed heating program, and the thermal inertia of the heating device is difficult to control during cooking. In addition, the amount of rice and water added by the user each time is different, resulting in very poor consistency in the cooking effect.

[0067] During the third period of the rice-cooking stage, the temperature of the inner surface of the insulation cover rises rapidly, and the temperature of the inner surface of the inner pot side 25 is higher than that of the inner surface of the inner pot bottom 22. During the fourth period of the rice-cooking stage, the temperature of the inner surface of the insulation cover rises slowly, indicating that the average power of the inner heating device 20 in the fourth period is greater than that in the third period, and the temperature of the inner surface of the inner pot side 25 is lower than that of the inner surface of the inner pot bottom 22.

[0068] After the fourth time period ends, the side heating device 20 and / or the top heating device stop working and continue for the fifth time period, after which the heat preservation stage begins. The fifth time period lasts 10-20 minutes, preferably 15 minutes. This multi-stage design of the rice-cooking stage extends the cooking time, ensuring the rice is cooked thoroughly by side heating. After entering the fifth time period, since the side heating device 20 also stops working, the side temperature begins to decrease, while the bottom temperature continues to decrease.

[0069] During at least a portion of the third time period, for example, the side heating power is higher, resulting in a relatively significant temperature rise in the sides to provide more heat to the food. During the fourth time period, the temperature of the inner surface of the inner pot side 25 is lower than the temperature of the inner surface of the inner pot bottom 22.

[0070] It should be noted that due to the residual heat of the heating element, the temperature of the corresponding part of the inner pot may not drop immediately after the heating element stops working; instead, it may rise. As a result, the temperature curve shows a certain lag relative to the power curve.

[0071] Insulation stage After the rice-cooking stage, the rice is cooked and the cooking process is complete. After cooking, a low heat can be used to keep the food warm during the keep-warm stage, allowing the user to enjoy hot food. The keep-warm stage typically maintains the food temperature at a set temperature (e.g., 40°C to 80°C at the bottom of the cooking container). The keep-warm stage usually lasts for a relatively long time (e.g., at least 30 minutes) and can be manually ended.

[0072] Regardless of the type of cooking appliance 10 or the type of cooking, the heat preservation stage mentioned in this application can refer to heat preservation performed after cooking is completed, or heat preservation performed separately according to the user's instructions.

[0073] The processes and steps described in all the preferred embodiments above are merely examples. Unless adverse effects occur, various processing operations can be performed in a different order than the above-described processes. The order of steps in the above processes can also be added, combined, or deleted according to actual needs.

[0074] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for descriptive purposes only and is not intended to limit the scope of this application. Features described in one embodiment may be applied, alone or in combination with other features, to another embodiment, unless that feature is not applicable in that other embodiment or is otherwise stated.

[0075] This application has been described through the above embodiments. However, it should be understood that the above embodiments are only for illustrative purposes. This application is not limited to the above embodiments. Many variations and modifications can be made based on the teachings of this application, and all such variations and modifications fall within the scope of protection claimed in this application.

Claims

1. A cooking utensil, characterized in that, The cooking appliance includes: A pot body, wherein the pot body is provided with an inner pot, wherein the inner pot is an uncoated inner pot; A lid that can be opened and closed is provided on the pot body. When the lid is closed on the pot body, a cooking space is formed between the lid and the inner pot. A bottom heating device is located below the inner pot; A side heating device and / or a top heating device, wherein the side heating device is disposed on the outer periphery of the side of the inner pot, and the top heating device is disposed on the top of the cooking space; A top temperature sensor or a bottom temperature sensor, wherein the top temperature sensor is used to monitor the top temperature of the inner pot, and the bottom temperature sensor is used to detect the bottom temperature of the inner pot; A control device electrically connected to the bottom heating device, the side heating device and / or the top heating device and the top temperature sensor or the bottom temperature sensor, the control device being configured to execute a cooking program including a boiling stage and a simmering stage. The boiling maintenance phase includes: During the first time period, the bottom heating device is controlled to operate in a first heating cycle, the first heating cycle having a first duty cycle. After the first time period ends, a second time period begins. During the second time period, the bottom heating device is controlled to operate in a second heating cycle, which has a second duty cycle. When the temperature T detected by the top temperature sensor 顶 Or the temperature T detected by the bottom temperature sensor 底 The increase in amplitude ΔT during the second heating cycle 顶 or △T 底 Exceeding the threshold △T 阈 Sometimes, or, When the second time period ends, the boiling maintenance phase ends and the rice simmering phase begins; The rice-cooking stage includes: controlling the bottom heating device to stop working, and controlling the side heating device and / or the top heating device to operate.

2. The cooking utensil according to claim 1, characterized in that, The first heating cycle is 30s~50s, the second heating cycle is 30s~50s, and the threshold temperature is 2℃~6℃.

3. The cooking utensil according to claim 1, characterized in that, The first time period is 5 min to 10 min, the second time period is 5 min to 10 min, and the average power of the bottom heating device in the first heating cycle is 30% to 50% of the rated power; The average power of the bottom heating device during the second heating cycle is 40% to 60% of its rated power.

4. The cooking appliance of claim 1, wherein, The rice-cooking stage includes: During the third time period, the side heating device and / or the top heating device are controlled to operate in a third heating cycle, the third heating cycle having a third duty cycle; During the fourth time period, the side heating device and / or the top heating device are controlled to operate in a fourth heating cycle, the fourth heating cycle having a fourth duty cycle.

5. The cooking appliance of claim 4, wherein, The third heating period is 2 to 5 minutes, and the average power of the side heating device and / or top heating device during the third heating cycle is 30% to 50% of the rated power. The fourth heating period is 5 min to 9 min, and the average power of the side heating device and / or top heating device in the fourth heating cycle is 20% to 50% of the rated power.

6. The cooking appliance of claim 4, wherein, The cooking process also includes a heat preservation stage, and the rice simmering stage further includes: after the fourth time period ends, controlling the side heating device and / or the top heating device to stop working and continue for a fifth time period, after which the heat preservation stage begins, and the fifth time period is 10 min to 20 min.

7. The cooking appliance of claim 4, wherein, The cooking process also includes: The water absorption stage includes: controlling the bottom heating device to heat the inner pot and make the temperature detected by the top temperature sensor or the bottom temperature sensor reach the target water absorption temperature, and ending the water absorption stage when the running time of the bottom heating device reaches a first preset time. The heating phase, which follows the water absorption phase, includes: controlling the bottom heating device to heat the inner pot with an average power greater than or equal to 80% of the rated power, determining the amount of rice based on the time it takes for the temperature detected by the top temperature sensor or the bottom temperature sensor to reach a first preset temperature, and ending the heating phase when the temperature detected by the top temperature sensor or the bottom temperature sensor reaches a second preset temperature, wherein the second preset temperature is greater than the first preset temperature. The boiling determination stage is between the heating stage and the boiling maintenance stage. The boiling determination stage includes controlling the bottom heating device to heat the inner pot and determining whether the contents of the pot are boiling based on the temperature detected by the top temperature sensor or the bottom temperature sensor.

8. The cooking appliance of claim 7, wherein, The target water absorption temperature is 55℃~59℃, and the first preset time is 5min~15min.

9. The cooking appliance of claim 7, wherein, The water absorption stage includes: When T 顶 or T 底 When the temperature is ≤50℃, the bottom heating device is controlled to operate in a fifth heating cycle, the fifth heating cycle having a fifth duty cycle, and the average power of the bottom heating device in the fifth heating cycle being greater than or equal to 80% of the rated power; When 50℃ < T 顶 or T 底 When the temperature is ≤55℃, the bottom heating device is controlled to operate in the sixth heating cycle, the sixth heating cycle having a sixth duty cycle, and the average power of the bottom heating device in the sixth heating cycle is 30%~80% of the rated power; When 55℃ < T 顶 or T 底 When the temperature is <59℃, the bottom heating device is controlled to operate in the seventh heating cycle, the seventh heating cycle having a sixth duty cycle, and the average power of the bottom heating device in the seventh heating cycle is less than or equal to 30% of the rated power.

10. The cooking appliance of claim 9, wherein, When the temperature T detected by the top temperature sensor 顶 Or the temperature T detected by the bottom temperature sensor 底 After the temperature first exceeds 55℃, if T 顶 or T 底 If the temperature is ≥59℃, the bottom heating device will stop working. 顶 or T 底 If the temperature is ≤55℃, the bottom heating device is controlled to heat at an average power of less than or equal to 30% of the rated power.

11. The cooking utensil according to claim 7, characterized in that, The first preset temperature is 60℃~80℃, and the second preset temperature is 75℃~85℃.

12. The cooking utensil according to claim 7, characterized in that, The heating phase includes: The bottom heating device is controlled to operate in an eighth heating cycle, the eighth heating cycle having an eighth duty cycle, and the average power of the bottom heating device in the eighth heating cycle being greater than or equal to 80% of its rated power. When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches the first preset temperature, the bottom heating device is controlled to operate in a ninth heating cycle. The ninth heating cycle has a ninth duty cycle. The average power of the bottom heating device in the ninth heating cycle is greater than or equal to 80% of the rated power. When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches the second preset temperature, the heating phase ends.

13. The cooking appliance of claim 12, wherein, When the time it takes for the temperature detected by the top temperature sensor or the bottom temperature sensor to reach the first preset temperature is less than or equal to 7 minutes, it is determined to be a milligram quantity. When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches the first preset temperature for a time greater than 7 minutes and less than or equal to 13 minutes, it is determined to be medium rice quantity. When the temperature detected by the top temperature sensor or the bottom temperature sensor reaches the first preset temperature for more than 13 minutes, it is determined to be the amount of rice. Among them, the fourth time period corresponding to the amount of medium rice is greater than the fourth time period corresponding to the amount of millet, and the fourth time period corresponding to the amount of large rice is greater than the fourth time period corresponding to the amount of medium rice.

14. The cooking appliance of claim 7, wherein, The determination of the boiling stage includes: The bottom heating device is controlled to operate in a tenth heating cycle, the tenth heating cycle having a tenth duty cycle, and the average power of the bottom heating device in the tenth heating cycle being greater than or equal to 70% of its rated power. When the temperature detected by the top temperature sensor or the bottom temperature sensor is greater than or equal to the third preset temperature, and the third preset temperature is greater than the second preset temperature, it is determined that the contents of the pot have boiled.

15. The cooking appliance of claim 14, wherein, The third preset temperature is 80℃~90℃; and / or the third preset temperature is 8℃~11℃ lower than the local boiling point.

16. The cooking appliance of claim 7, wherein, The determination of the boiling stage includes: The bottom heating device is controlled to operate in a tenth heating cycle, the tenth heating cycle having a tenth duty cycle, and the average power of the bottom heating device in the tenth heating cycle being greater than or equal to 70% of its rated power. If the temperature detected by the top or bottom temperature sensor remains unchanged within 20 to 40 seconds, it is determined that the contents of the pot have boiled.

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