CA3225210A1 - An inner pot assembly, a cooking utensil, and a control method of the cooking utensil - Google Patents

Abstract

An inner pot assembly (30), a cooking utensil (100), and a control method of the cooking utensil (100). The inner pot assembly (30) comprises an inner pot (40) having a height of 90-200 mm, and a steamer basket (50) supported in the inner pot (40) and removable therefrom. The steamer basket (50) comprises a rice accommodating chamber that is enclosed by its bottom wall (51) and side wall (52) connected with each other. The steamer basket (50) is fitted to the inner pot (40) so that a receiving space (60) is formed between the steamer basket (50) and the inner pot (40). The bottom wall (51) comprises a water rising part (54), a guiding part (56) extending outward from an outer border of the water rising part (54), and a water descending part (53) extending outward from an outer border of the guiding part (56), the water rising part (51) being arranged higher than the water descending part (53). The water rising part (54) is provided with a plurality of first through holes (57) and the water descending part (53) is provided with a plurality of second through holes (58). The guiding part (56) is a water-impermeable zone extending from the outer most borders of the first through holes (57) to the inner most borders of the second through holes (58). The maximum height difference between the water rising part (54) and the water descending part (53) being H1, and the height difference between any one of the first through holes (57) and any one of the second through holes (58) being H2, wherein, 3 mm?H1?40 mm, and/or 3 mm ?H2?40 mm.

Description

An Inner Pot Assembly, a Cooking Utensil, and a Control Method of the Cooking Utensil Field of the Invention The present invention relates to the technical field of kitchen utensils and in particular relates to an inner pot assembly, a cooking utensil, and a control method of the cooking utensil.
Background of the Invention Currently, in existing low-sugar rice cookers, the top outer border of a steamer basket is supported on the top outer border of an inner pot, and a water passing cylinder is provided below the steamer basket. The bottom of the water passing cylinder is spaced apart from the inner surface of the inner pot and is provided with a structure with openings. Water in the inner pot, after being heated, can rise into the steamer basket via the water passing cylinder, so as to rinse rice accommodated in the steamer basket. However, rice cookers with this type of structure have a limited pressure at the inner side of the water passing cylinder, which results in poor water rising and therefore non-ideal sugar lowering effects.
In view of this, the present invention provides an inner pot assembly, a cooking utensil, and a control method of the cooking utensil, so as to at least partially solve the problem in the prior art.
Summary of the Invention A series of concepts in simplified form have been introduced in the Summary of the Invention section, which will be described in further detail in the Detailed Description section. The Summary of the Invention section of the present invention is not intended to limit the key features and essential technical features of the claimed technical solutions, nor is it intended to define the scope of protection of the claimed technical solutions.
In order to at least partially solve the above-described problem, according to a first aspect of the present invention, an inner pot assembly for a cooking utensil is disclosed, comprising:
- an inner pot having a height of [90, 200] mm; and - a steamer basket supported in the inner pot and removable therefrom, comprising a bottom wall and a side wall connected with the bottom wall, the bottom wall and the side wall enclosing an accommodating chamber for accommodating rice, the steamer basket is fitted to the inner pot so that a receiving space is formed between the bottom wall and the inner pot, or between the bottom wall, the side wall, and the inner pot, the bottom wall comprising a water rising part, a guiding part extending outward from an outer border of the water rising part, and a water descending part extending outward from an outer border of the guiding part, the water rising part being arranged higher than the water descending part, rice being accommodated on the water rising part, the guiding part, and the water descending part, the water rising part being provided with a plurality of first through holes communicating the accommodating chamber with the receiving space and allowing water, but not rice, to pass through, the water descending part being provided with a plurality of second through holes communicating the accommodating chamber with the receiving space and allowing water, but not rice, to pass through, and the guiding part being a water-impermeable zone extending from the outer most border of the first through holes to the inner most borders of the second through holes, a maximum height difference between the water rising part and the water descending part being H1, and a height difference between any one of the first through holes and any one of the second through holes being H2, wherein, 3 mm H1 40 mm, and/or 3 mm H2 40 mm, so that during cooking, boiling water in the receiving space is able to enter the accommodating chamber via the first through holes.
The inner pot assembly according to the present invention defines the guiding height of the guiding part by defining the height difference between the water rising part and the water descending part or the height difference between the first through holes and the second through holes so that an appropriate pressure is formed in the space enclosed by the guiding part by water vapor, gas, and air bubbles after water starts boiling. Such pressure enables boiling water in the receiving space to enter the steamer basket via the first through holes and rush through the upper surface of rice, then spread from the middle to the surrounding, and finally fall back into the inner pot via the second through holes or the first through holes. The water can soak and rinse all the rice and thus effectively ensure a sugar lowering effect and the flavor of the rice.
By fitting the steamer basket to the inner pot, a receiving space is formed between the bottom wall of the steamer basket and the inner port, or between the bottom wall, the side wall of the steamer basket, and the inner pot, i.e., a sealed or quasi-sealed chamber is formed between the steamer basket and the inner pot. There are three zones capable of pressure relief in the receiving space, i.e., the location of fitting between the steamer basket and the inner pot, the first through holes, and the second through holes. As there is no gap or only a tiny gap at the location of fitting between the steamer basket and the inner pot, boiling water inside the receiving space will encounter a higher resistance in that zone than at the first through holes and the second through holes. Therefore, it is less possible for boiling water inside the receiving space to pass through the location of fitting,

2 and even if boiling water passes through the location of fitting, the quantity will be relatively small and its impact on the water rising effect at the first through holes will be limited.
When water inside the receiving space is heated to a certain temperature, gas and air bubbles can be generated. Air bubbles rise to the surface of the water and generate a pressure in the receiving space as gas increases. VVhen water is heated to boil, boiling air bubbles emerge with water out of the water surface under the effect of the pressure and can accumulate at the inner side of the bottom of the guiding part. As the first through holes are higher than the second through holes, when rice is placed in the accommodating chamber of the steamer basket, the thickness of rice placed at the first through holes will be smaller than that of rice placed at the second through holes, so that the resistance of rice encountered by water at the first through holes is smaller than that encountered at the second through holes. The sum of potential energy of the resistance of rice grains encountered at the first through holes by water and air bubbles in the receiving space and their own gravity is smaller than the sum of potential energy of the resistance of rice grains encountered at the second through holes by water and air bubbles and their own gravity. Therefore, under the effect of the pressure, water and air bubbles in the receiving space are able to rise to the accommodating chamber of the steamer basket via the first through holes provided at the water rising part, and, in the accommodating chamber, soak and rinse rice in the steamer basket. Then, starch and sugar contents in the rice in the steamer basket can fall back into the receiving space via the second through holes and the first through holes, thus achieving the objective of lowering sugar in rice and preventing rice from being partially cooked. It can be understood that there may be a small quantity of boiling water that enters the steamer basket via the second through holes, but its quantity will be so small that it will only have very limited impact on the water rising effect of the first through holes.
By providing the water rising part, the guiding part, and the water descending part on the bottom wall, and with rice being accommodated on the water rising part, the guiding part, and the water descending part, water admitting and water discharging of the steamer basket can be directly achieved by the bottom wall which supports rice. This structure is very simple and cost-saving. In addition, as water rushes into the steamer basket via the bottom wall, i.e., from below rice grains, it can stir the rice grains from below so that the rice grains are rolled and thus providing a better rinsing effect of the rice grains.
Optionally, 8 mm H1 30mm, and/or 8 mm H2 30 mm.
Optionally, 10 mm < H1 20mm, and/or 10 mm < H2 <20 mm.

3 In the inner port assembly according to the present invention, the height difference between the water rising part and the water descending part or the height difference between the first through holes and the second through holes can be further optimized so that the sugar lowering effect and flavor of the rice are still improved.
Optionally, the water rising part comprises any one of a plane, a curved face or a combination thereof.
With the inner port assembly according to the present invention, the shape of the water rising part can be flexibly designed.
Optionally, the area of the projection of the water rising part on a horizontal plane is equal to or larger than 80 mm2.
The inner port assembly according to the present invention can ensure that the water rising part has enough area for providing water rising holes and thus ensure the sugar lowering effect and flavor of rice.
Optionally, the water descending part comprises any one of a plane, a curved face or a combination thereof.
With the inner port assembly according to the present invention, the shape of the water descending part can be flexibly designed.
Optionally, the bottom wall is rotationally symmetric with the central axis of the steamer basket as rotation axis.
With the inner port assembly according to the present invention, the bottom wall has a regular shape and is easy to process.
Optionally, the guiding part comprises any one of a cylindrical side face, a truncated cone side face, or an arc-shaped face, or any combination thereof.
With the inner port assembly according to the present invention, the shape of the guiding part can be flexibly designed.
Optionally, a top part of the guiding part and a bottom part of the guiding part are both horizontal planes and are connected by a revolution face in the form of a side face of a truncated cone.
With the inner port assembly according to the present invention, the guiding part is designed to be in the form of a side face of a truncated cone, so that the steamer basket is

4 easy to process.
Optionally, the water rising part is a horizontal plane, and/or the water descending part is a horizontal plane.
With the inner port assembly according to the present invention, the bottom wall is designed to present an upward protrusion in the form of a truncated cone, so that the steamer basket is easy to process and produce.
Optionally, when the steamer basket is placed in the inner port, an inner surface of the inner pot is in contact with the steamer basket so that the steamer basket is fitted to the inner pot by contact, wherein, the inner surface of the inner pot is provided with an arc-shaped structure, a bevel structure, an inward protruding structure, or a step structure extending towards the inside of the inner pot, so as to come into contact with and support the steamer basket.
In the inner pot assembly according to the present invention, the inner pot is configured to support the steamer basket, which has a simple and compact structure and makes it convenient to produce, use, and maintain the product. At the same time, with the steamer basket in contact with the inner pot, after water starts boiling, water vapor, gas, and air bubbles in the receiving space can concentrate as much as possible at the guiding part, generating a sufficient pressure at the guiding part and ensuring water rising effects.
Optionally, an outer surface of the steamer basket is provided with a sealing member extending circumferentially that comes into contact with the inner pot when the steamer basket is placed in the inner pot, so that the steamer basket is tightly fitted to the inner pot.
In the inner pot assembly according to the present invention, the steamer basket is in sealing contact with the inner pot, which better limits the pressure relief at the location of fitting and thus better ensures the water rising at the water rising part.
Optionally, an inner surface of the inner pot is provided with an inward protruding rib extending circumferentially, when the steamer basket is placed in the inner pot, the distance between the inward protruding rib and an outer surface of the steamer basket being smaller than or equal to 1 mm, so that the steamer basket is fitted to the inner pot by proximity; or an outer surface of the side wall of the steamer basket is provided with an outward protruding rib extending circumferentially, when the steamer basket is placed in the inner pot, the distance between the outward protruding rib and an inner surface of the inner pot being smaller than or equal to 1 mm, so that the steamer basket is fitted to the inner pot by

5 proximity.
With the inner pot assembly according to the present invention, the steamer basket contacts or approaches the inner pot as much as possible so that after water starts boiling, water vapor, gas, and air bubbles in the receiving space concentrate as much as possible at the guiding part, generating a sufficient pressure at the guiding part and ensuring the water rising through the first through holes.
It has been demonstrated by experiments that, when the distance between the inner pot and the steamer basket at the location of fitting is not larger than 1 mm, the pressure relief at the location of fitting can be effectively controlled so that after water starts boiling, water vapor, gas, and air bubbles in the receiving space concentrate as much as possible at the guiding part and generate a sufficient pressure at the guiding part, thus ensuring the water rising through the first through holes.
Optionally, the steamer basket is fitted to the inner pot by contact or by proximity at a location of fitting, and the distance between the steamer basket and the inner pot at the location of fitting is equal to or smaller than 1 mm.
With the inner pot assembly according to the present invention, the steamer basket contacts or approaches the inner pot as much as possible so that the receiving space forms a sealed or quasi-sealed space, and after water starts boiling, water vapor, gas, and air bubbles in the receiving space concentrate as much as possible at the guiding part, generating a sufficient pressure at the guiding part and ensuring the water rising through the first through holes.
It has demonstrated by experiments that, when the distance between the inner pot and the steamer basket at the location of fitting is not larger than 1 mm, the pressure relief at the location of fitting can be effectively controlled so that after water starts boiling, water vapor, gas, and air bubbles in the receiving space concentrate as much as possible at the guiding part and generate a sufficient pressure at the guiding part, thus ensuring the water rising through the first through holes.
Optionally, the location of fitting is not higher than the top of the water rising part.
With the inner pot assembly according to the present invention, the location of fitting between the inner pot and the steamer basket is as low as possible so as to effectively control the pressure relief at the location of fitting, ensuring that a sufficient pressure is generated at the guiding part and ensuring the water rising through the first through holes.
Optionally, the maximum distance H3 between the location of fitting and the top of the

6

7 water rising part in the vertical direction is such that 1 H1/H3 < 15.
With the inner pot assembly according to the present invention, the location of fitting between the inner pot and the steamer basket is as low as possible so as to effectively control the pressure relief at the location of fitting, ensuring that a sufficient pressure is generated at the guiding part and ensuring the water rising through the first through holes.
Optionally, the plurality of first through-holes are uniformly distributed, and/or the plurality of second through holes are uniformly distributed along the circumferential direction of the water descending part.
With the inner pot assembly according to the present invention, the first through holes and the second through holes are uniformly distributed, so that rice can be soaked and rinsed uniformly.
Optionally, the steamer basket is made of metal, wood material, or plastic material, wherein, the steamer basket is integrally formed, or its bottom wall is integrally formed.
With the inner pot assembly according to the present invention, the steamer basket has a wide range of material choices and is simple to process.
Optionally, the steamer basket further comprises a holding part extending circumferentially from the top of the side wall and being depressed towards the central axis of the steamer basket relative to the side wall, and/or the side wall is provided with a plurality of side wall through holes provided in a spaced manner along the circumferential direction of the steamer basket and located higher than the location of fitting between the steamer basket and the inner pot.
With the inner pot assembly according to the present invention, the holding of the steamer basket by a user is facilitated thanks to the holding part. By providing side wall through holes at a location above the location of fitting between the steamer basket and the inner pot, excessive water and foams in the steamer basket can be discharged into the inner pot via the side wall through holes, thus reducing the possibility of overflowing from the pot.
Optionally, an inner surface of the inner pot is provided with at least one water level line, when the steamer basket is placed in the inner pot, at least one inner pot water level line is lower than the second through holes, and/or at least one water level line is lower than the first through holes but not lower than the second through holes.
With the inner pot assembly according to the present invention, by providing a water level line, a user can be instructed to add an appropriate amount of water based on the quantity of rice. For a water level line below the second through holes, the water level should be set lower than the second through holes so that rice will not be soaked in water, which can not only ensure the uniformity of rice flavor, but also prevent rice from turning bad when being soaked for a long time during a reservation function. The water level line can also be lower than the first through holes but not lower than the second through holes, which can instruct a user to add an appropriate amount of water based on needs. For example, when the quantity of rice is relatively large, it can ensure that more water enters the steamer basket to rinse the rice. When there is only one water level line, the water level line can be provided according to actual need, either at a location below the second through holes, or at a location lower than the first through holes but not lower than the second through holes.
When there are a plurality of water level lines, some of them can be arranged lower than the second through holes and some of them lower than the first through holes but not lower than the second through holes, so as to satisfy cooking needs of different quantities of rice. For example, when cooking one cup of rice (approximately 150 g), the water level line is below the second through holes, because only a small amount of water is needed for rinsing the rice and satisfying cooking needs. When cooking multiple cups of rice, the water level line can be at a location higher than the second through holes but lower than the first through holes, so that there is a sufficient amount of water to ensure rice rising and cooking effects for a large quantity of rice. It can be understood that the water level lines can also be all lower than the second through holes, or all lower than the first through holes but not lower than the second through holes. Various forms of water level lines can be flexibly provided according to needs.
Optionally, at least one water level line is lower than the second through holes and has a height difference with the second through holes which is smaller than or equal to 10 mm.
With the inner pot assembly according to the present invention, at least some or all of water level lines are lower than the second through holes, and their height difference with the second through holes is larger than 0 but smaller than or equal to 10 mm, which can prevent rice from being soaked by water and allowing water to be heated to boil quickly and to execute the step of rinsing more quickly, and at the same time, ensuring water rising through the first through holes.
Optionally, the area of the projection of the bottom wall on a horizontal plane is [11000, 46000] mm2, and/or the area of the guiding part is equal to or larger than 700 mm2, and/or the volume of the receiving space is [200,2000] ml.
In the inner pot assembly according to the present invention, structural parameters are appropriately set so as to ensure that the receiving space can receive sufficient water and

8 the water can effectively rise at the water rising part.
A second aspect of the present invention provides a cooking utensil comprising the inner pot assembly described above and heating means for heating the inner pot assembly.
The cooking utensil according to the present invention defines the guiding height of the guiding part by defining the height difference between the water rising part and the water descending part or the height difference between the first through holes and the second through holes so that an appropriate pressure is formed in the space enclosed by the guiding part by water vapor, gas, and air bubbles after water starts boiling.
Such pressure enables boiling water in the receiving space to enter the steamer basket via the first through holes and rush through the upper surface of rice, then spread from the middle to the surrounding, and finally fall back into the inner pot via the second through holes or the first through holes. The water can soak and rinse all the rice and thus effectively ensure a sugar lowering effect and the flavor of the rice.
Optionally, the nominal power P of the heating means is such that 600W P
1500W.
The cooking utensil according to the present invention sets an appropriate nominal power, which not only ensures that water inside the receiving space quickly boils to produce sufficient water vapor, gas and air bubbles, but also controls the product's development costs and use-costs.
A third aspect of the present invention provides a control method of a cooking utensil, which can be applied to the cooking utensil described above, the control method sequentially comprising the following processes:
a preheating process in which the heating means is controlled to heat the inner pot assembly so that the temperature of the inner pot rises;
a rice rinsing and cooking process in which the heating means is controlled to intermittently heat the inner pot assembly so that water inside the receiving space rises and enters the accommodating chamber via the first through holes and the water that has entered the accommodating chamber, after soaking and rinsing the rice, falls back into the receiving space via the first through holes and/or the second through holes;
a rice steaming process in which the heating means is controlled to heat the inner pot assembly.
According to the control method of the present invention, in the rice rinsing and cooking process, water inside the receiving space boils, and under the effect of the guiding part,

9 water vapor, gas, and air bubbles enter the accommodating chamber via the first through holes and rush through the upper surface of rice, and then water spreads from the middle to the surrounding to soak and rinse the rice so that starch and sugar contents in the rice fall into the inner pot with the water. Thus, the objective of lowering sugar can be achieved, and the rice has a uniform flavor and is not partly uncooked.
Optionally, the cooking utensil further comprises a temperature sensor for detecting the temperature in a cooking space, and in the preheating process, when the temperature sensor detects that the temperature inside the cooking space reaches a preset temperature T, the control method proceeds to the rice rinsing and cooking process, the 1(:) preset temperature T being such that 65 C T 90 C.
Optionally, the preset temperature T is such that 65 C <T 80 C.
According to the control method of the present invention, food materials are first preheated. In the preheating process, rice can be soaked by water vapor so that rice can uniformly absorb water, ensuring the flavor of cooked rice.
Optionally, in the rice rinsing and cooking process, rice is rinsed multiple times, and during each rinsing, the heating means performs heating for a first preset duration and then stops heating for a second preset duration, when the number of times of rinsing reaches N, or when the duration of the rice rinsing and cooking process reaches a preset rinsing duration, the control method proceeds to the rice steaming process, wherein, N
is a natural number.
According to the control method of the present invention, rice is rinsed multiple times in the rice rinsing and cooking process while being fully soaked by water, so that the sugar lowering effect and flavor of the rice are better.
Optionally, the heating means is an electromagnetic heating element, the first preset duration is [5, 25] s, and the second present duration is [10, 35] s, wherein, N is a natural number larger than or equal to 8 but smaller than or equal to 12, and/or the preset rinsing duration is [10, 30] minutes.
Optionally, the heating means is a heating plate, the first preset duration is [7, 28] s, and the second present duration is [8, 25] s, wherein, N is a natural number larger than or equal to 18 but smaller than or equal to 30, and/or the preset rinsing duration is [5, 15]
minutes.
With the control method according to the present invention, the heating means can be different hardware parts and the operational parameters of the rice rinsing and cooking process are set based on the specific hardware performance so as to achieve the effect of lowering sugar and a uniform flavor of the rice.
Optionally, the heating power during the preheating process is higher than that of the rice steaming process, and the heating power during the rice rinsing and cooking process is higher than that of the rice steaming process.
The control method according to the present invention appropriately sets the heating power of each cooking stage, so as to effectively ensure the sugar lowering and uniform flavor of the rice. In the preheating process, a relatively high heating power is used, which can make the rice soaked as much as possible by water vapor and help ensure a uniform flavor of cooked rice. In the rice rinsing and cooking process, a relatively high heating power is used, which can make the water inside the receiving space boil to produce sufficient water vapor, gas, and air bubbles, so as to generate a sufficient pressure at the guiding part to ensure water rising and achieve the sugar lowering and uniform flavor of rice. After rice has been fully soaked and rinsed, in the rice steaming process, there is no longer need to have a large quantity of water enter the steamer basket, and the heating power can be lowered to save energy.
Optionally, the control method further comprises a rice braising process and when the duration of the rice steaming process reaches a preset rice steaming duration, the control method proceeds to the rice braising process, wherein, the heating power of the rice braising process is lower than that of the rice steaming process.
According to the control method according of the present invention, in the rice braising process, the heating power can be further lowered to save energy. At the same time, water inside the receiving space is prevented from being dried out and the degree of gelatinization of rice is not increased.
Description of the Drawings The accompanying drawings of the present invention listed below constitute part of the present application for understanding the present invention. In the accompanying drawings, examples of embodiments of the present invention and their description are illustrated to explain the principle of the present invention.
In the accompanying drawings:
Fig. 1 is a sectional view of a partial structure of a cooking utensil according to a preferred embodiment of the present invention;
Fig. 2 is a sectional view of the inner pot assembly of the cooking utensil shown in Fig. 1;
Fig. 3 is a view in perspective of the steamer basket of the inner pot assembly shown in Fig. 2;
Fig. 4 is a top view of the steamer basket shown in Fig. 3;
Figs. 5 to 11 are sectional views of the inner pot assembly of a cooking utensil according to some embodiments of the present invention;
Fig. 12 is a top view of the steamer basket of the inner pot assembly of a cooking utensil according to a specific embodiment of the present invention;
Fig. 13 is a sectional view of the inner pot assembly of a cooking utensil according to a specific embodiment of the present invention;
Fig. 14 is a top view of the steamer basket of the inner pot assembly shown in Fig. 13; and Figs. 15 to 18 are sectional views of the inner pot assembly of a cooking utensil according to specific embodiments of the present invention.
Description of references:
100: cooking utensil

10: pot body 20: lid body 30: inner pot assembly 40: inner pot 41: flange 42: inward protruding part 43: step part 43A: step face 44: inward protruding rib 50: steamer basket 51: bottom wall 52: side wall 52A: sealing element 53: water descending part 54: water rising part 55: upper edge 56: guiding part 57: first through hole 58: second through hole 59: supporting part 60: receiving space 65: guiding chamber 61: holding part 62: side wall through hole 70: heating means 80: temperature sensing assembly A: central axis of the steamer basket : outer diameter of the guiding part / inner diameter of the water descending part D2: maximum outer diameter of the bottom wall of the steamer basket D3: inner diameter of the guiding part / outer diameter of the water rising part D4: diameter of the opening of the inner pot E: angle between the central axis and the line connecting the two ends of the guiding part in the sectional plane passing the central axis of the steamer basket H1: height of the bottom wall! maximum height difference between the water rising part and the water descending part H2: height difference between the first through holes and the second through holes H3: height difference between the location of fitting and the top of the water rising part H4: height of the steamer basket H5: height of the inner pot M: lower border of the guiding part in the sectional plane passing the central axis of the steamer basket N: upper border of the guiding part in the sectional plane passing the central axis of the steamer basket S: location of fitting between the steamer basket and the inner pot Detailed Description of the Invention In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to a person skilled in the art that the embodiments of the present invention may be practiced without one or more of those details. In other examples, some technical features known in the art are not described in order to avoid confusion with the embodiments of the present invention.
For a thorough understanding of the embodiments of the present invention, detailed structures will be presented in the following description. Obviously, the implementation of the embodiments of the present invention is not limited to specific details familiar to a person skilled in the art. It should be noted that ordinal numbers such as "first" and "second" used in the present specification are merely references, and do not have any other meanings, such as a specific order. In addition, for example, the term "first part"
does not imply by itself the presence of a "second part", nor does the term "second part"
by itself imply the presence of a "first part", The terms "upper", "lower", "front", "rear", "left"
and "right" and similar expressions used in the present invention are for the purpose of description and not limitation.
The present invention provides a cooking utensil and an inner pot assembly of a cooking utensil. The cooking utensil according to the present invention can be an electric rice cooker, and can have functions such as porridge making, soup making, and food steaming in addition to a rice cooking function.
A cooking utensil 100 and an inner pot assembly 30 according to a preferred embodiment of the present invention will be described in detail below in reference to Figs. 1 to 4.
As shown in Fig. 1, the cooking utensil 100 mainly comprises a pot body 10 and a lid body 20 provided above the pot body 10 and capable of opening and closing. The inner pot assembly 30 is provided in the pot body 10. When the lid body 20 covers the pot body 10, a cooking space is formed between the lid body 20 and the inner pot assembly 30. The pot body 10 can be configured to have the shape of a cuboid with rounded corners or any other appropriate shape and has a receiving part in the shape of a cylinder.
The inner pot assembly 30 is configured to be freely placed in the receiving part or removed from the receiving part to facilitate the cleaning of the inner pot assembly 30.
In addition, heating means 70, control means (not illustrated), and a temperature sensing assembly 80 are further provided in the pot body 10. The heating means 70 is provided at the bottom of the inner pot assembly 30, for example located below the inner pot assembly 30, so as to heat the food in the inner pot assembly 30. The control means can for example be a Micro Control Unit (or MCU for short) for controlling the cooking process of the cooking utensil. The temperature sensing assembly 80 is used for detecting the temperature of the inner pot assembly 30 and can be provided at the middle of the bottom of the inner pot assembly 30 or beside the inner pot assembly 30. A top temperature measuring element (not illustrated) can also be further provided on the lid body 20 for detecting the temperature in the cooking space. The heating means 70, the temperature sensing assembly 80, and the top temperature measuring element are all electrically connected to the control means. The temperature sensing parts send the measured temperature to the control means so that the control means can perform a more precise control of for example the heating means 700 based on temperature information.
It should be noted that in the present invention, directional terms "upper"
and "lower" refer to those directions determined when the cooking utensil 100 is placed upright and with the lid body 20 in a closed state.
As shown in Figs. 1 to 4, the inner pot assembly 30 mainly comprises an inner pot 40 and a steamer basket 50 supported in the inner pot 40 and removable therefrom.
Preferably, the steamer basket 50 is configured to be of a structure that is rotationally symmetric relative to its central axis A. Preferably, the central axis A of the steamer basket 50 extends in a vertical direction. The steamer basket 50 comprises a bottom wall 51 and a side wall 52 extending upward from an outer border of the bottom wall 51. The bottom wall 51 and the side wall 52 enclose an accommodating chamber for accommodating rice.
Preferably, the side wall 52 is in the form of a cylinder. The maximum outer diameter D2 of the bottom wall 51 of the steamer basket 50 is smaller than the diameter D4 of the opening of the inner pot 40 so as to easily place the steamer basket 50 in the inner pot 40.
It can be understood that the steamer basket 50 can also be configured as a structure that is not rotationally symmetric.
The bottom wall 51 comprises a water rising part 54, a guiding part 56, and a water descending part 53. The water rising part 54 is located in the middle, the guiding part 56 extends outward from the outer border of the water rising part 54, and the water descending part 53 extends outward to the side wall 52 from the outer border of the guiding part 56. In other words, the bottom wall 51 of the steamer basket 50 sequentially comprises, outwardly in the radial direction, the water rising part 54, the guiding part 56, and the water descending part 53. The water rising part 54 is higher than the water descending part 53. The water rising part 54 and the guiding part 56 enclose a protrusion protruding upward from the bottom wall 51, while the water descending part 53 comprises the lowest part of the bottom wall 51 and is located on the outer periphery of the protrusion.
Rice can be accommodated on the water rising part 54, the guiding part 56 and the water descending part 53. The water descending part 53 can be in contact with the inner surface of the inner pot 40 so as to form a sealed or quasi-sealed receiving space 60 between the bottom wall 51 and the inner pot 40. The receiving space 60 is used for receiving water.
During cooking, boiling water in the receiving space 60 can enter the steamer basket 50 so as to soak and rinse the rice.
Preferably, the shape of the water rising part 54 matches that of the guiding part 56 so that the water rising part 54 transitions smoothly to the guiding part 56 at their junction; the shape of the water descending part 53 matches that of the guiding part 56 so that the water descending part 53 transitions smoothly to the guiding part 56 at their junction.
Preferably, the bottom wall 51 and the side wall 52 are integrally formed (the whole steamer basket 50 is integrally formed), or the water rising part 54, the guiding part 56 and the water descending part 53 are integrally formed (the whole bottom wall 51 is integrally formed). Preferably, the steamer basket 50 is made of metal, wood material or plastic material. The steamer basket has a wall thickness of 0.2 mm to 10 mm, preferably 0.3 to 3 mm. Preferably, the bottom wall 51 is configured to be rotationally symmetric relative to the central axis A.
The water rising part 54 is provided with first through holes 57 communicating with the receiving space 60 and the water descending part 53 is provided with second through holes 58 communicating with the receiving space 60. As the water rising part 54 is higher than the water descending part 53, the first through holes 57 are higher than the second through holes 58. The guiding part 56 is a water-impermeable zone extending from the outer most border of the first through holes 57 to the inner most border of the second through holes 58. The guiding part 56 is relatively inclined from the outer bottom to the inner top. As shown in Fig. 12, the upper border of the guiding part 56, the inner border of the guiding part 56 and the outer border of the water rising part 54 are the same border, i.e., the outer most border of the first through holes 57 having an outer diameter D3. The lower border of the guiding part 56, the outer border of the guiding part 56, and the inner border of the water descending part 53 are the same border, i.e., the inner most border of the second through holes 58 having an inner diameter Dl. The inner diameter D1 of the water descending part 53 is larger than the outer diameter D3 of the water rising part 54.
Preferably, the first through holes 57 are provided at the highest location of the water rising part 54 (thus the highest location of the bottom wall 51), and the second through holes 58 are provided at the lowest location of the water descending part 53 (thus the lowest location of the bottom wall 51). Preferably, the first through holes 57 and the second through holes 58 are uniformly distributed. For example, the first through holes 57 are provided at equal distance along the circumferential direction of the water rising part 54, and the second through holes 58 are provided at equal distance along the circumferential direction of the water descending part 53. Preferably, the first through holes 57 and the second through holes 58 are configured as circular through holes. It can be understood that the shapes of the first through holes 57 and the second through holes 58 are not limited to the present embodiment. Based on needs, the first through holes 57 and the second through holes 58 can also be configured to have the shape of an oval, a polygon, or any other appropriate shape. Preferably, the diameter of each first through hole 57 is smaller than or equal to 3 mm or the area of each first through hole 57 is smaller than or equal to 8 mm2, while the diameter of each second through hole 58 is smaller than or equal to 3 mm or the area of each second through hole 58 is smaller than or equal to 8 mm2. With such dimensions, rice grains in the steamer basket 50 cannot fall into the receiving space 60 via the first through holes 57 and the second through holes 58.
A quasi-sealed receiving space 60 in which water is received is formed between the bottom wall 51 and the inner pot 40. As shown in Figs. 5 to 11, generally, the water level will not exceed the bottom wall 51 of the steamer basket, i.e., a vacant guiding chamber 65 is left between the water surface and the bottom wall 51. The space below the protrusion enclosed by the water rising part 54 and the guiding part 56 forms a main part of the guiding chamber 65. During cooking, as the heating temperature rises, air pressure in the guiding chamber 65 gradually increases, and the water in the receiving space 60 generates more and more water vapor and air bubbles, which further increase the air pressure in the guiding chamber 65. For safety and to prevent water from splashing out, air pressure is generally below 4 kPa, for example, it can rise to approximately 1.8 kPa. As the guiding part 56 is relatively inclined from the outer bottom to the inner top, when water is heated to boil, boiling bubbles will emerge out of the water surface with water under the effect of pressure, and concentrate inside the bottom of the water rising part 54 under the collecting effect of the guiding part 56. When the surface of the rice is relatively flat, as the water rising part 54 is higher than the water descending part 53, the thickness of rice at the water rising part 54 is lower than that at the water descending part 53, which produces a resistance difference, i.e. the resistance of rice at the first through holes 57 is smaller than that at the second through holes 58. Therefore, under the effect of pressure, water and air bubbles in the receiving space 60 rise into the steamer basket 50 until the upper surface of rice through the first through holes 57 provided on the water rising part 54. Thus, water and gas enter the inside of the steamer basket 50 from the water rising part 54 located relatively in the middle, then spread to the surrounding. Then, water falls back into the receiving space 60 via the surrounding second through holes 58, thereby soaking and rinsing rice inside the steamer basket 50. Therefore, starch and sugar contents in the rice inside the steamer basket 50 can fall back into the receiving space 60 via the second through holes 58 together with water, thus achieving the objective of reducing sugar in the rice. At the same time, the surface of rice located in the middle and that of rice located at the circumference can both be soaked by water, which can effectively prevent rice from being half-cooked.
In the present invention, under the collecting effect of the guiding part 56, a large number of air bubbles concentrate inside the bottom of the water rising part 54 where a local high-pressure zone is formed. At the same time, the resistance of rice at the water rising part 54 is relatively small. Thus, the first through holes 57 can achieve the objective of making water rise and water can rush to the upper surface of rice. It can be understood that in the present invention, it is possible that some water may fall back into the receiving space 60 via the first through holes 57 and that some water may enter the steamer basket 50 via the second through holes 58.
Specifically, the water rising part 54 may comprise a plane face (as shown in Fig. 2), an upward protruding curved face, a downward depressing curved face, or a combination of a plane face and a curved face (as shown in Fig. 5 and Fig. 6). The water descending part 53 may comprise a plane face (as shown in Fig. 2), an upward protruding curved face, a downward depressing curved face, or a combination of a plane face and a curved face (as shown in Fig. 7 and Fig. 8). The guiding part 56 may comprise any one of a cylinder side face, a truncated cone side face, or an arc-shaped face, or any combination thereof (as shown in Figs. 9 to 11). In the embodiment shown in Figs. 1 to 4, the bottom wall 51 is configured to be rotationally symmetric with the central axis A of the steamer basket 50 as its axis. The water rising part 54 is configured to be a circular plane and the water descending part 53 is configured to be a ring-shaped plane. The top and bottom of the guiding part 56 are configured to be planes and respectively connected with the water rising part 54 and the water descending part 53. The top and bottom of the guiding part 56 are connected with each other via a revolution face in the shape of a truncated cone side wall. In the embodiment shown in Figs. 13 and 14, the water rising part 54 is configured to be in the shape of a regular polygon, and the guiding part 56 is configured to be constituted of a plurality of inclined flat walls spliced together.
In order to make water rise and ensure that water can adequately soak the rice inside the steamer basket 50, the height of the water rising part 54 is a crucial factor that controls the amount of water that rises. When the maximum height difference H1 between the water rising part 54 and the water descending part 53 (i.e., the height of the bottom wall 51) is relatively small, the collecting effect of the guiding part 56 cannot be adequately achieved, and the difference of rice thickness on the bottom wall 51 is not significant (i.e. rice accumulating at the water rising part 54 is also relatively high), which makes it difficult for water entering the steamer basket 50 at the water rising part 54 to rush through the upper surface of rice. Therefore, the surface of the rice can hardly be soaked by water, which leads to half-cooked or relatively hard rice. On the other hand, when the height H1 of the water rising part 54 is too large, the first through holes 57 are too far away from the water surface in the receiving space 60, water brought up by air bubbles in the guiding chamber 65 is relatively little, and air pressure in the guiding chamber 65 cannot rise sufficiently. In this case, the amount of water that rises via the first through holes 57 is not sufficient, which makes it difficult for the surface of rice to be soaked by water, easily leading to a half-cooked surface and a relatively poor sugar lowering effect.
The inventors of the present invention have obtained by experiments and tests the impact of the height difference H1 between the water rising part 54 and the water descending part 53 on the cooking results. In the experiments, the nominal power of the heating means 70 is 1200 W, the volume of the inner pot 40 is 4 L, the diameter D4 of the opening of the inner pot 40 is 201 mm, the volume of the steamer basket 50 is 2.6 L, the maximum outer diameter D2 of the bottom wall 51 of the steamer basket is 198 mm, the outer diameter D1 of the guiding part 56 is 165 mm, the total area of all the first through holes 57 is 117 mm2, the total area of all the second through holes 58 is 197 mm2, the quantity of rice accommodated in the steamer basket 50 is 3 cups (approximately 450 g), and the amount of water accommodated in the receiving space 60 is 850 ml.
As shown in Table 1, when the height difference between the water rising part 54 and the water descending part 53 H1 < 3 mm, the sugar content (reducing sugar) of rice is relatively high. Further, it is hard for water entering the steamer basket 50 to rush through the rice surface since it encounters a relatively large resistance of rice at the first through holes 57, which makes it difficult for the surface of rice to be soaked by water and results in a water content that is lower than industry standards. On the other hand, when the height different between the water rising part 54 and the water descending part 53 H1 >
40 mm, although the sugar content (reducing sugar) satisfies industry standards, the water content is lower than industry standards because the height difference H1 is so large that the gravitational potential energy to be overcome by air bubbles generated in the receiving space in order to rise to the first through holes 57 increases, which renders the amount of rising water insufficient and makes it impossible for water entering the steamer basket 50 to soak the surface of rice. When the height difference H1 between the water rising part 54 and the water descending part 53 is such that: 3 mm H1 40 mm, the amount of water that rises via the first through holes 57 is sufficient for water entering the steamer basket 50 to relatively easily rush through the surface of rice and thus fully soak the rice, so as to ensure a consistency of the rice and therefore provide a good sugar lowering effect and better flavor of the rice. More preferably, H1 is such that: 8 mm H1 30 mm, providing a better sugar lowering effect. More preferably, H1 is such that: 10 mm 5 H1 20 mm, providing an optimal sugar lowering effect.
Table 1 Impact of Height Difference H1 between Water Rising Part 54 and Water Descending Part 53 on Cooking Results H1 Water Reducing Sugar Degree of Resistant Starch (mm) Content (%) Content (mg/100 g) Gelatinization (%) Content (%) 1 55.7 0.348 79.6 14.410 2 57.3 0.329 83.3 13.635 3 58.1 0.290 85.1 11.972 5 60.8 0.296 88.3 9.315 8 61.1 0.275 89.6 9.129 10 61.5 0.231 89.8 9.714 15 63.2 0.227 90.2 9.948 20 62.3 0.234 91.5 10.149 25 60.4 0.268 90.6 9.986 30 59.1 0.271 87.3 10.288 35 58.5 0.292 87.4 10.327 40 58.2 0.281 85.6 12.862 45 56.9 0.293 81.6 12.571 It should be noted that, in industry standards, the water content is 58% to 65%, the reducing sugar content is < 0.3 mg/100 g, the degree of gelatinization is 85%
to 95%, and the resistant starch content is 8%. In addition, in a conventional cooking mode in which rice is fully immerged in water, the reducing sugar content of the rice obtained is approximately 0.529 mg/100 g, and the resistant starch content is approximately 5.40%.
Therefore, the sugar lowering effect of the cooking utensil 100 according to the present invention is not only better than the conventional cooking mode but also better than industry standards.
In the present invention, the first through holes 57 mainly serve as holes for water to rise through, and the second through holes 58 mainly serve as holes for water to descend through. The height difference between the first through holes 57 and the second through holes 58 can essentially represent the height difference between the water rising part 54 and the water descending part 53. In the present invention, any one of the first through holes 57 and any one of the second through holes 58 has a height difference H2, and preferably, H2 is such that: 3 mm H2 40 mm. More preferably, H2 is such that:
8 mm H2 <30 mm. Still more preferably, H2 is such that: 10 mm < H2 <20 mm.
The first through holes 57 and the second through holes 58 have an appropriate height difference so that the thickness of rice placed above the first through holes 57 will be smaller than that of rice placed above the second through holes 58 and thus the resistance (gravity) of rice at the first through holes 57 is smaller than that at the second through holes 58. The sum of the resistance of rice grains encountered by water and air bubbles in the receiving space 60 and their own gravitational potential energy at the first through holes 57 is smaller than the sum at the second through holes 58.
Therefore, under the effect of pressure, water and air bubbles in the receiving space 60 are able to rise to the accommodating chamber of the steamer basket 50 via the first through holes 57 and rush through the upper surface of rice, then soak and rinse the rice in the steamer basket 50 in the accommodating chamber. Then, starch and sugar contents in the rice in the steamer basket 50 fall back into the receiving space 60 with water via the second through holes 58 and the first through holes 57, thus achieving the objective of lowering sugar in rice and preventing rice from being half-cooked.
The guiding part 56 is arranged to be inclined so as to collect water bubbles at the inner side of the bottom of the guiding part 56. Through the invention, it has been discovered that the angle E in the longitudinal sectional plane passing through the central axis A of the steamer basket 50 can also affect the amount of rising water and thus affect cooking results. As shown in Figs. 5 to 11, the angle E is the angle formed between the line connecting the two ends (M and N points) of the intersection line between the guiding part 56 and the longitudinal sectional plane and the central axis A of the steamer basket 50.

The M point represents the inner most border of the second through holes 58 in the longitudinal sectional plane, and the N point represents the outer most border of the first through holes 57 in the longitudinal sectional plane. The M and N points should be either both located at borders of the first through holes 57 and the second through holes 58 located at an upper surface of the bottom wall 51, or both at borders of the first through holes 57 and the second through holes 58 located at a lower surface of the bottom wall 51.
In Figs. 5 to 11, the M and N points are both located at borders of the first through holes 57 and the second through holes 58 located at the lower surface of the bottom wall 51.
When the above-described angel E is too small, the area of the axial sectional plane of the guiding part 56 (i.e., the area of the axial sectional plane of the three-dimensional shape formed by the space enclosed by the water rising part 54, the guiding part 56 and the water level, for example, the area of the axial sectional plane of the truncated cone enclosed by the water rising part 54 and the guiding part 56) and the space inside the guiding part 56 (i.e., the space enclosed by the water rising part 54, the guiding part 56 and the water level, for example, the truncated cone enclosed by the water rising part 54 and the guiding part 56) are relatively small, thus the volume of water and air bubbles that concentrate inside the bottom of the guiding part 56 is relatively small.
Therefore, the amount of water that rises via the first through holes 57 is relatively small, making it difficult for rice to be thoroughly soaked, easily leading to half-cooked or relatively hard rice and a relatively poor sugar lowering effect. On the other hand, when the above-described angle E is too large, the area of the axial sectional plane and the space inside the guiding part 56 are relatively large. Thus, a relatively large amount of water and air bubbles in the receiving space 60 needs to be concentrated (i.e., a relatively large pressure is required) for them to rise to the level of the first through holes 57. In addition, under a given pressure, the speed of water in the receiving space 60 flowing through the first through holes 57 is reduced, which is not conducive to water rising.
Therefore, only a relatively small amount of water can rise via the first through holes 57, making it difficult for rice to be thoroughly soaked, and easily leading to half-cooked or relatively hard rice and a relatively poor sugar lowering effect. The inventors of the present invention have discovered through experiments and tests that when the above-described angle E
is such that 30" E 85", the amount of water that rises via the first through holes 57 can be ensured so as to fully soak the rice and therefore ensure a good sugar lower effect and the flavor of the rice. More preferably, the above-described angle E is such that: 55 E
80 .
It can be understood that the ratio F between the area of the guiding part 56 and the area of the projection of the guiding part 56 on a horizontal plane can also reflects the size of the angle E. Preferably, F is such that: 1 < F 6.

The ratio between the height difference H1 between the water rising part 54 and the water descending part 53 and the angle E can also affect cooking results. VVhen the ratio of the height difference H1 to the angle E is relatively small, i.e., when the height difference H1 between the water rising part 54 and the water descending part 53 is relatively small or the angle E is relatively large, it can be seen from the above description that neither situation is conductive to water rising, easily leading to half-cooked or hard rice.
VVhen the ratio of the height difference H1 to the angle E is relatively large, i.e., the height difference H1 between the water rising part 54 and the water descending part 53 is relatively large or the angle E is relatively small, it can be seen from the above description that neither situation is conducive to water rising, either. In fact, in this case, the amount of water that rises via the first through holes 47 is relatively small, making it difficult for rice to be thoroughly soaked, easily leading to half-cooked or hard rice and a poor sugar lowering result. The inventors of the present invention have discovered through experiments and tests that when the ratio of the height difference H1 between the water rising part 54 and the water descending part 53 to the angle E is such that 0.035 mmr 5 H1/E 5 1.33 mmr, it is relatively easy for water and air bubbles in the receiving space 60 to rush through the surface of rice and the amount of water that rises through the first through holes 57 can be ensured, so that water entering the steamer basket 50 can fully soak the rice and therefore the sugar lowering result is relatively good and the flavor of the rice is better.
Preferably, the ratio of the height difference H1 to the angle E is such that 0.12 mm/
H1/E 5 0.36 mm/ .
It can be understood that the angle E, which reflects the degree of inclination of the guiding part 56, and the height H1 of the bottom wall 51 affect the volume V
of the space enclosed by the water rising part 54 and the guiding part 56. The larger the angle E or the height H1 is, the larger the volume V will be; the smaller the angle E or the height H1 is, the smaller the volume V will be. As described above, cooking results will be affected if the angle E and the height H1 are excessively large or small. In other words, the angle E and the height H1 have appropriate value ranges. Therefore, the volume V also has an appropriate value range. Preferably, the volume V is such that: 26000 mm3 5 V

MM3.
It can be understood that the ratio of the maximum outer diameter D3 of the water rising part 54 to the minimum inner diameter D1 of the water descending part 53 can also reflect the size of the above-described angle E. Therefore, the ratio of D3 to D1 should have an appropriate value range. Preferably, 0.02 5 D3/D1 5 0.5. More preferably, 0.1 0.25. D1 is preferably 100-240 mm. D3 is preferably 10-60 mm.
It can be understood that to ensure sufficient rising of water, the areas of the water rising part 54 and the guiding part 56 cannot be too small. Otherwise, the volume V
may be too small, or the height H1 may be too small, or the angle E may be too large.
Preferably, the area of the water rising part 54 is equal to or larger than 80 mm2, and the area of the guiding part 56 is equal to or larger than 700 mm2.
It can be understood that the total area of the first through holes 57 and the total area of the second through holes 58 cannot be too small. Otherwise, the speed of water rising or descending will be reduced, which is not conducive to thoroughly soaking and rinsing rice with water. VVhen the total area of the first through holes 57 decreases, the time for water to rise will be prolonged and the corresponding cooking time will also be prolonged. At the same time, a decrease in the total area of the first through holes 57 means a decrease in the area of the water rising part 54, which increases the pressure in the guiding chamber 65 and the rising water is squirted out, causing a risk when opening the lid.
A decrease in the area of the second through holes 58 will hinder the descending of water and result in water accumulation in certain zones, which is not conducive to reducing the sugar content of rice. Generally, the total area of the first through holes 57 is equal to or larger than 20 mm2, and the total area of the second through holes 58 is equal to or larger than 50 mm2.
But the total areas of the first through holes 57 and of the second through holes 58 cannot be too large either. When the total area of the first through holes 57 increases, the distribution range of the first through holes 57 becomes larger, so that the rising water flow is dispersed, which reduces the flow speed and pressure, and makes it difficult to rush through the water rising part 54. Further, an excessively large total area of the second through holes 58 will increase the amount of water that enters the steamer basket 50 via the second through holes 58, and thus reduces the amount of water rising through the water rising part 54, which will also affect the cooking results, especially easily causing an uneven flavor. In addition, when the total areas of the first through holes 57 and the second through holes 58 are too large, the areas of the water rising part 54 and the water descending part 53 will increase, which may affect the area and the angle of inclination of the guiding part 56. Preferably, the total area of the first through holes 57 ranges from 60 to 600mm2, and the total area of the second through holes 58 ranges from 100 to 600mm2.
More preferably, the total area of the first through holes 57 ranges from 60 to 400mm2, and the total area of the second through holes 58 ranges from 100 to 400mm2.
It can be understood that in order to ensure the above-described area of the water rising part 54, area of the guiding part 56, total area of the first through holes 57, and total area of the second through holes 58, the bottom wall 51 should have a sufficient outer diameter.
Preferably, the area of the projection of the bottom wall 51 on a horizontal plane is 11000-46000 mm2.
It can be understood that the larger the maximum outer diameter D2 of the bottom wall 51 is, the more rice can be accommodated inside the steamer basket 50. In this case, a larger amount of rising water is needed so as to fully soak and rinse the rice. Therefore, the dimensions of the water rising part 54 and the guiding part 56, which play a leading role in the water rising function of the bottom wall 51, should match the dimensions of the steamer basket 50. Preferably, the ratio of the area of projection of the guiding part 56 on a horizontal plane to the area of projection of the bottom wall 51 on a horizontal plane ranges from 0.25 to 0.9. Preferably, the ratio of the maximum outer diameter D3 of the water rising part 54 to the maximum outer diameter D2 of the bottom wall 51 is such that:
0.05 < D3/D2 0.5.
Generally, the height H5 of the inner pot 40 is 90-200 mm, preferably 100 mm to 155 mm.
The inventors of the present invention have discovered through experiments that when the volume of the receiving space 60 ranges from 200 ml to 2000 ml, the amount of water received in the receiving space 60 can meet the needs of the quantity of rice in the steamer basket 50. In order to ensure the volume of the receiving space 60, the dimensions of the steamer basket 50 should match those of the inner pot 40. In particular, the height H4 of the steamer basket 50 should match the height H5 of the inner pot 50.
Preferably, 0.5 < H4/H5 0.9.
It can be understood that the larger the height H4 of the steamer basket is, the larger the quantity of rice that can be accommodated in the steamer basket 50 will be, which may increase the thickness of rice at the water rising part 54. As described above, if the thickness of rice at the water rising part 54 increases, resistance to water rising will increase and cooking results will be affected. On the other end, an increase in the height difference H1 between the water rising part 54 and the water descending part 53 (i.e. the height of the bottom wall 51) can reduce the thickness of rice at the water rising part 54.
As described above, the height H1 of the bottom wall 51 should be within an appropriate range. Therefore, the height H4 of the steamer basket 50 should be within an appropriate range as well so that the height H1 of the bottom wall 51 matches the height H4 of the steamer basket 50. Preferably, 0.05 H1/H4 0.4. More preferably, 0.08 H1/H4 0.3.
The steamer basket 50 is supported in the inner pot 40. In some embodiments according to the present invention, the steamer basket 50 contacts with the inner surface of the inner pot 40 with its bottom wall 51 so that the inner pot 40 can support the steamer basket 50 while achieving the fitting of the steamer basket 50 to the inner pot 40 by contact.
In an embodiment not illustrated, the steamer basket 50 can contact with the inner surface of the inner pot 40 with its side wall so that the inner pot 40 can support the steamer basket 50 while achieving the fitting of the steamer basket 50 to the inner pot 40 by contact.

In another embodiment not illustrated, the steamer basket 50 can contact with the inner surface of the inner pot 40 with both its bottom wall 51 and its side wall so that the inner pot 40 can support the steamer basket 50 while achieving the fitting of the steamer basket 50 to the inner pot 40 by contact As shown in Figs. 1 to 3, the steamer basket 50 further comprises a supporting part 59 extending circumferentially and provided at the outer most border of the water descending part 53. The supporting part 59 connects the bottom wall 51 and the side wall 52 of the steamer basket 50 and is in the shape of an arc in the axial sectional plane of the steamer basket 50. The supporting part 59 is in contact with the inner surface of the inner pot 40 along a circumferential direction and is supported on the inner surface of the inner pot 40 so as to form a sealed or relatively sealed receiving space 60 between the bottom wall 51 and the inner pot 40. Preferably, the location S of fitting between the steamer basket 50 and the inner pot 40 (i.e., the location where the supporting part 59 contacts with and supported by the inner pot 40) is at the same level as or higher than the lowest location of the water descending part 53 of the bottom wall 51. Preferably, the location S
of fitting between the steamer basket 50 and the inner pot 40 is at the same level as or lower than the highest location of the water rising part 54.
The location S of fitting being not higher than (at the same level as or lower than) the location of the highest point of the bottom wall 51 (i.e., the highest point of the water rising part 54) can effectively control the pressure relief at the location S of fitting. As the sealing between the supporting part 59 and the inner surface of the inner pot 40 is sealing by contact, not absolute sealing, gas can pass through the gap between the two.
In other words, the location S of fitting also has a pressure relief capacity like the first through holes 57 and the second through holes 58. Water in the receiving space 60, after being heated to a certain temperature, can produce water bubbles, which will emerge out of the water surface. When the location S of fitting is relatively low, water bubbles that emerge out of the water surface will reach the location S of fitting. When the gap at the location S
of fitting is very small, due to the tension of water, it will be difficult for gas to pass through the gap at the location S of fitting and thus the resistance encountered by gas, water vapor, and water bubbles at the location S of fitting is higher than the resistance encountered at the first through holes 57. Therefore, the water rising at the water rising part 54 will not be affected. When the location S of fitting becomes higher, it is more difficult for water bubbles to reach the height of the location S of fitting and easier for gas to leak via the location S of fitting. The higher the location S of fitting is, the higher the pressure relief capacity at the location S of fitting will be, and the larger the impact on the water rising at the water rising part 54 will be. On the other hand, when the location S of fitting is at a relatively large distance from the water surface in the receiving space 60, the space for receiving gas and air bubbles enclosed by the supporting part 59 and the inner pot 40 is larger. Similar to guiding part 56, the supporting part 59 can also collect gas and air bubbles in the receiving space 60, so that gas in the guiding chamber 65 is diverted. The higher the location S of fitting is, the higher the flow diverting capacity at the location S of fitting will be, and the higher the pressure relief capacity at the location S
of fitting will be, and thus the larger the impact on the water rising at the water rising part 54 will be.
Therefore, the location S of fitting should be arranged as low as possible and the gap at the location S of fitting should be as small as possible.
When the location S of fitting is not lower than (at the same level as or higher than) the location of the lowest point of the bottom wall 51 (i.e., the lowest point of the water descending part 53), the circumferential fitting between the outer surface of the steamer basket 50 and the inner pot 40 is facilitated so that the gap at the location S of fitting is as small as possible, while enabling a flexible choice among various structures and shapes for the water descending part 53.
The inventors of the present invention have discovered through experiments and tests that the location S of fitting is preferably not higher than the highest location of the water rising part 54 and not lower than the lowest location of the water descending part 53. The height difference in the vertical direction between the location S of fitting and the top of the water rising part 54 being H3, when the ratio between the height H1 of the bottom wall 51 and the height difference H3 is such that 1 H1/H3 15, more water will rise via the first through holes 57, thereby improving the rice rinsing by water. Therefore. the sugar lowering effect and the rice's flavor are better.
In the embodiment shown in Figs. 1 to 3, as the inner pot 40 and the steamer basket 50 are in contact with each other at the location S of fitting, with a very small gap between the two, a quasi-sealing structure is formed. Thus, the resistance for gas escaping via the location S of fitting is very large. Therefore, the resistance encountered by water at the first through holes 57 is smaller than the resistance encountered at the second through holes 58 and or at the location S of fitting of the supporting part 59. Thus, water rising into the steamer basket 50 via the first through holes 57 can rush through the rice, to its surface, and spread to the surrounding, achieving full soaking of rice. When heating is stopped, pressure inside the receiving space 60 drops, and liquid in the steamer basket 50 can flow back into the receiving space 60 via the first through holes 57 and the second through holes 58. By repeating this, the cooking process of rinsing rice is achieved.
In the embodiment shown in Figs. 5 to 11, the contact between the steamer basket 50 and the inner pot 40 is the same as in the embodiment shown in Fig. 2. In such embodiments, the inner pot 40 supports the steamer basket 50 by an arc-shaped inner pot side wall. It can be understood that the inner pot 40 can also support the steamer basket 50 by an inclined bevel formed on the side wall of the inner pot. In other words, in the axial sectional plane of the inner pot 40, its side wall comprises an inclined straight line instead of a curved line, the straight line being inclined from the inner bottom to the outer top of the inner pot 40.
In the embodiment shown in Fig. 15, the support of the steamer basket 50 and the fitting between the inner pot 40 and the steamer basket 50 are still achieved by circumferential contact between the inner pot 40 and the bottom wall 51 of the steamer basket.
In this embodiment, the inner pot 40 is provided with an inward protruding part 42 extending in the circumferential direction and radially towards the inner side of the inner pot 40. The inward protruding part 42 is arranged to come into contact with the bottom wall 51. The contact location where the inward protruding part 42 contacts with the bottom wall 51 is the location S of fitting between the steamer basket 50 and the inner pot 40.
In other words, the inner pot 40 supports the steamer basket 50 by contact with an inward protruding inner pot side wall. It can be understood that in this embodiment, preferably, the height difference H3 in the vertical direction between the location S of fitting and the top of the water rising part 54 and the height H1 of the bottom wall 51 are such that 1 H1/H3 15.
In the embodiment shown in Fig. 16, the support of the steamer basket 50 and the fitting between the inner pot 40 and the steamer basket 50 are still achieved by circumferential contact between the inner pot 40 and the bottom wall 51 of the steamer basket.
In this embodiment, the inner pot 40 is provided with a step part 43 extending in the circumferential direction on its side wall and radially inward, so that the inner diameter of the lower part of the inner pot 40 is smaller than that of its upper part. The step face 43A of the step part 43 is a plane extending horizontally from the side wall of the inner pot 40 towards the inside of the inner pot so that the bottom wall 51 of the steamer basket can be supported on the step face 43A. Specifically, the bottom wall 51 is supported on the step face 43A so as to be in contact with the inner pot 40, the location where the bottom wall 51 contacts with the step face 43A is the location S of fitting between the steamer basket and the inner pot. In other words, the inner pot 40 supports the steamer basket 50 by its side wall having an inward extending step. It can be understood that in this embodiment, preferably, the height difference H3 in the vertical direction between the location S of fitting and the top of the water rising part 54 and the height H1 of the bottom wall 51 are such that 1 H1/H3 15.
It can be understood that whether the supporting part 59 is configured to be in an arc shape, a straight shape, or a sharp angle, the inner pot 40 can always support the steamer basket 50 by contact by an arc-shaped side wall, an inclined side wall, an inward protruding side wall, or a side wall having an inward extending step.

In the above described embodiment wherein the inner pot 40 supports the steamer basket 50 by contacting with the bottom wall 51 of the steamer basket, the fitting between the inner pot 40 and the steamer basket 50 should be understood as follows: the inner surface of the inner pot 40 being provided with an inner pot fitting part and the outer surface of the bottom wall 51 of the steamer basket being provided with a steamer basket fitting part, the steamer basket fitting part coming in contact with the inner pot fitting part when the steamer basket 50 is placed in the inner pot 40 so that the steamer basket 50 is fitted to the inner pot 40. The location where the steamer basket fitting part is in contact with the inner pot fitting part is the location S of fitting between the steamer basket and the inner pot, wherein, the height difference H3 in the vertical direction between the location S of fitting and the top of the water rising part 54 and the height H1 of the bottom wall 51 are such that 1 H1/H3 15.
In some other embodiments according to the present invention, the steamer basket 50 is provided with a connecting part by which the steamer basket is supported in the inner pot 40, the steamer basket 50 being fitted to the inner pot 40 at a location other than the connecting part.
Specifically, the connecting part can be an upper edge 55 of the steamer basket 50 by which the steamer basket 50 is suspended on an opening flange 41 of the inner pot. As shown in Figs. 17 and 18, the steamer basket 50 comprises an upper edge 55 extending outward from a top border of the side wall 52, the opening of the inner pot 40 is provided with a flange 41, and the upper edge 55 is supported on the flange 41. In other words, the steamer basket 50 is suspended in the inner pot 40. In such embodiments, the bottom wall 51 of the steamer basket is not in contact with the inner pot. It can be understood that in such mode of supporting, there is a gap between the side wall 52 of the steamer basket and the side wall of the inner pot. When water in the receiving space 60 starts to boil, the gap can divert water vapor, gas and air bubbles produced by boiling water. To reduce the impact of the gap on the water rising at the water rising part 54, such embodiments respectively adopt the following measures to ensure the water rising at the water rising part 54.
In the embodiment shown in Fig. 17, the outer surface of the steamer basket 50 (for example, the outer surface of its side wall 52) is provided with a sealing element 52A
extending circumferentially. For example, the outer surface of the side wall 52 can be provided with a circumferential groove. Then the sealing element 52A made of an elastic material (for example, rubber or silica gel) is bonded to or directly sleeved in the groove such that the sealing element 52A protrudes from the outer surface of the side wall 52.
When the steamer basket 50 is placed in the inner pot 40, the sealing element 52A can be in contact with the inner surface of the inner pot 40 so as to block the gap between the side wall of the steamer basket and the side wall of the inner pot. In this embodiment, the inner pot 40 and the steamer basket 50 are fitted by means of the sealing element 52A.
The steamer basket fitting part is materialized by the sealing element 52A and the inner pot fitting part is provided at the location of the inner surface of the inner pot 40 corresponding to the sealing element 52A. The location of contact between the inner pot fitting part and the steamer basket fitting part is the location of fitting.
Preferably, the location S of the sealed fitting is not higher than the top of the water rising part 54.
In the embodiment shown in Fig. 18, the inner surface of the inner pot 40 is provided with an inward protruding rib 44 extending circumferentially and approaching the outer surface of the steamer basket 50 (for example, the outer surface of its side wall 52).
In such embodiment, the fitting between the inner pot 40 and the steamer basket 50 can be understood as fitting by proximity. The inner pot fitting part of the inner pot 40 is materialized by the inward protruding rib 44 and the steamer basket fitting part is the part of the outer surface of the side wall 52 corresponding to the inward protruding rib. It can be understood that in this embodiment, when the steamer basket 50 is placed in the inner pot 40, there may exist a gap between the inner pot fitting part and the steamer basket fitting part. Preferably, at the location S of fitting, the distance between the inner pot 40 and the steamer basket 50 does not exceed 1 mm.
It can be understood that the outer surface of the steamer basket 50 can also be provided with an outward protruding rib extending circumferentially and approaching the inner surface of the inner pot 40. In such embodiment of fitting by proximity, the steamer basket fitting part is materialized by the outward protruding rib at its outer surface, and the inner pot fitting part is the part of the inner surface of the inner pot 40 corresponding to the outward protruding rib. Preferably, at the location S of fitting, the distance between the inner pot 40 and the steamer basket 50 does not exceed 1 mm.
Preferably, in an embodiment of fitting by proximity, the location S of fitting is not higher than the top of the water rising part 54. Preferably, the height difference H3 between the location S of fitting and the top of the water rising part 54 and the height H1 of the bottom wall 51 are such that: 1 H1/H3 15.
In an embodiment not illustrated, the bottom part of the steamer basket 50 is provided with a plurality of supporting feet extending downward or a supporting cylinder for coming into contact with the bottom wall of the inner pot 40. The supporting feet or the supporting cylinder are the connecting part of the steamer basket. The steamer basket 50 and the inner pot 40 are fitted at a location other than the supporting feet or supporting cylinder, for example, fitted by means of a sealing element or a protruding rib.

In the embodiments shown in Figs. 17 and 18, the receiving space 60 is delimited by the bottom wall 51 of the steamer basket, the side wall 52 of the steamer basket, and the inner pot 40.
In the embodiments shown in Figs. 2, 5-11, and 15-16, the inner pot 40 and the steamer basket 50 are fitted by contact. But it can be understood that, due to the imperfections of the processing methods, it cannot be guaranteed that the inner pot 40 and the steamer basket 50 remain in contact all along the circumference. In other words, in these embodiments, a gap may exist between the inner pot fitting part and the steamer basket fitting part. Preferably, when the steamer basket 50 is placed in the inner pot 40, the 1(:) distance between the inner pot fitting part and the steamer basket fitting part does not exceed 1 mm (smaller than or equal to 1 mm). Thus, even if there exists a gap between the inner pot fitting part and the steamer basket fitting part, as the gap is very small, a quasi-sealed chamber can be formed between the side wall 51 of the steamer basket and the inner pot 40, or between the bottom wall 51 of the steamer basket, the side wall 52 of the steamer basket, and the inner pot 40. The above range of the gap size can ensure that the resistance to boiling water in the receiving space 60 at the gap is larger than that at the first through holes 57 and that at the second through holes 58 so that it is difficult for boiling water in the receiving space 60 to pass through the gap, thus ensuring the water rising at the water rising part 54.
In sum, when the steamer basket 50 is placed in the inner pot 40, the steamer basket fitting part and the inner port fitting part are in contact with each other or close to each other, the distance between the steamer basket 50 and the inner pot at the location of fitting being smaller than or equal to 1 mm.
As shown in Fig. 2, the steamer basket 50 further comprises a holding part 61 configured to extend circumferentially from the top of the side wall 52 and to be depressed toward the central axis A of the steamer basket 50 relative to the side wall 52, so that the steamer basket 50 can be easily held and moved by a user.
In addition, the side wall 52 of the steamer basket is provided with a plurality of side wall through holes 62. Excessive water and foams in the steamer basket 50 can be discharged to the inner pot 40 via the side wall through holes 62, reducing the possibility of overflowing. The side wall through holes 62 are provided at the upper part of the side wall 52. Specifically, the side wall through holes 62 are higher than the steamer basket fitting part. In other words, the side wall through holes 62 are provided above the location of fitting so that it is difficult for gas and air bubbles generated by boiling water in the receiving space 60 to enter the steamer basket 50 via the side wall through holes 62. This disposition can also limit the pressure relief capacity of the location of fitting and thus ensuring the water rising at the water rising part 54. Preferably, the side wall through holes 62 are provided in a spaced manner along the circumference of the side wall 52 so that excessive water and foams in the steamer basket 50 can be discharged into the inner pot 40 via the side wall through holes 62, thus reducing the possibility of overflowing The inner surface of the inner pot 40 is provided with at least one water level line (not illustrated), different water level lines corresponding to different quantities of rice. When the steamer basket 50 is placed in the inner pot 40, at least one water level line is lower than the second through holes 58, for example, at 0-10 mm below the second through holes. When the water level is lower than the second through holes 58, rice is separated from water and will only come into contact with water during cooking and when water is boiling thus enters the accommodating chamber via the first through holes 57.
Thus, all the rice can be rinsed and soaked at the same time, which helps maintain the consistency of the flavor of rice. In addition, with the water level being below the second through holes 58, a relatively small amount of water is enough for cooking, which helps save water while enabling water in the receiving space 60 to be heated to boil more quickly. In other words, this enables a quicker execution of the rinsing step, which will be described in detail below.
At the same time, for a cooking utensil with a reservation function, water in the receiving space 60 will not come into direct contact with rice in the accommodating chamber of the steamer basket 50 during the waiting period, thereby avoiding foul odors.
Especially in summertime, if rice is soaked in water for a long time, foul odors are more significant, and rice may even become spoiled and therefore inedible. By providing an water level line below the second through holes 58, foul odors and spoiling can be avoided and the duration of reservation can be prolonged. It can be understood that, based on needs, for different quantities of rice or different dimensions of the inner pot and of the steamer basket, when the steamer basket 50 is placed in the inner pot 40, a water level line at the inner surface of the inner pot 40 can also be lower than the first through holes 57 but higher than or at the same level as the second through holes 58.
Further, the inner surface of the steamer basket 50 is provided with at least one steamer basket water level line (not illustrated). Different volumes of water can be added based on needs while ensuring that the amount of water is as small as possible so that water in the receiving space 60 can be heated to boil more quickly, i.e., the rinsing step (which will be described in detail below) can be executed more quickly.
The plurality of water level lines on the inner pot 40 and the steamer basket 50 provides indications of the amounts of water corresponding to different quantities of rice for a user's reference.
The rice cooking process of the cooking utensil 100 is described below.

First, an appropriate amount of water is added to the inner pot 40 according to the water level line. If there are a plurality of water level lines in the inner pot 40, then an amount of water corresponding to the quantity of rice to be cooked is added. Next, rice is placed in the steamer basket, and the steamer basket, with the rice accommodated in it, is placed in the inner pot. Then, a corresponding rice cooking program is selected for cooking.
In a preferred embodiment, the rice cooking process of the cooking utensil 100 sequentially comprises the following steps.
1. Reservation process The reservation process means that a user places food in the cooking utensil in advance and then sets a reservation duration and a cooking mode (such as rice cooking or porridge making) so that the cooking utensil can complete the cooking based on the requirements of the cooking mode at the moment when the reservation duration has elapsed from the current moment. As described above, when the water level is lower than the second through holes 58, it can be ensured that rice and water are separated and a longer reservation duration can be set. When reservation is not needed, this step can be skipped and the cooking utensil proceeds directly to the preheating process.
2. Preheating process In the preheating process, the control means controls the heating means 70 to heat the inner pot assembly 30. Preferably, the heating power is 1200 W. When a top temperature measuring element detects that the temperature has reached a preset temperature T, the cooking utensil proceeds to the rice rinsing and cooking process. In the present embodiment, the preset temperature T is such that 65 C T 90 C. Preferably, the present temperature T is such that 65 C < T 80 C.
3. Rice rinsing and cooking process The rice rinsing and cooking process is an important step that allows to achieve the sugar lowering effect of the cooking utensil according to the present invention.
The control means controls the heating means 70 to intermittently heat the inner pot assembly 30 so that boiling water in the receiving space 60 rises and enters the accommodating chamber via the first through holes 57. Water having entered the accommodating chamber, after soaking and rinsing water, falls back into the receiving space 60 via the first through holes 57 and the second through holes 58. In the rice rinsing and cooking process, rice is rinsed multiple times, for example N times (N
being a natural number). During each rinsing, the heating means 70 performs heating for a first preset duration and then stops heating for a second preset duration.
The nominal power P of the inner pot assembly 30 can adjust the pressure in the receiving space 60 and how many air bubbles are generated, thereby affecting the amount of water rising via the first through holes 57 and further affecting the cooking results. When the nominal power P of the inner pot assembly 30 is too small, for example when the nominal power P < 600 W, gas and air bubbles produced in the receiving space 60 are not sufficient, and the pressure in the receiving space 60 is relatively low, which is therefore not conducive to water rising. Thus, the amount of water rising via the first through holes 57 is relatively little so that rice can hardly be soaked by water thoroughly, easily resulting 1(:) in half-cooked or hard rice. VVhen the nominal power P of the inner pot assembly 30 is too large, the heating means is costly itself and having a high electricity consumption, which increases the cost of use for a user. When the nominal power P of the inner pot assembly 30 is such that 600 W P 1500 W, the amount of water rising via the first through holes 57 can be ensured so that water can fully soak the rice, thus ensuring the sugar lowering effect and the flavor of the rice. At the same time, the costs of the heating means are relatively low, in addition to the relatively low electricity consumption, which can reduce the costs of use and improves the user's utilization experience.
In the rice rinsing and cooking process, preferably, the heating power is 600-1500 W.
More preferably, the heating power is 1200 W. During each rinsing, boiling water can rise and enter the accommodating chamber via the first through holes 57 during heating, and water having entered the accommodating chamber soaks and rinses water. When the heating is stopped, water in the accommodating chamber falls back into the receiving space.
When the number of times of rinsing reaches N (N times of heating), or the duration of the rice rinsing and cooking process reaches a preset rinsing duration, the cooking utensil proceeds to the rice steaming process.
Optionally, the heating means 70 is an electromagnetic heating element, the number of times of rinsing N is 8 to 12, the first preset duration is 5-25 s, the second preset duration is 10-35 s, and the preset rinsing duration is 10-30 minutes.
Optionally, the heating means 70 is a heating plate, the number of times of rinsing N is 18 to 30, the first preset duration is 7-28 s, the second preset duration is 8-25 s, and the preset rinsing duration is 5-15 minutes.
4. Rice steaming process In the rice steaming process, the control means controls the heating means 70 to heat the inner pot assembly 30 so that water in the receiving space 60 boils and rice is cooked by steaming with water vapor. Preferably, in the rice steaming process, the heating power is 700 W. When the duration of the rice steaming process reaches a preset rice steaming duration (for example, 6-10 minutes), the cooking utensil proceeds to the rice braising process.
5. Rice braising process After completing the rice steaming process, the cooking utensil proceeds to the rice braising process. The rice braising process is a later stage in the cooking process, during which, a relatively high temperature is still maintained in the inner pot 40 and the steamer basket 50 after the rice steaming process, so as to ensure that food is fully cooked by steaming. When the duration of the rice braising process reaches a preset rice braising duration (for example, 8-15 minutes), the cooking utensil proceeds to the heat preservation process. Preferably, in the rice braising process, the heating power is 500 W.
The heating power of the preheating process is higher than that of the rice steaming process and that of the rice braising process. The heating power of the rice rinsing and cooking process is higher than that of the rice steaming process and that of the rice braising process. The heating power of the rice steaming process is higher than that of the rice braising process.
6. Heat preservation process When the rice braising process is completed, the substantive cooking work is completed.
But sometimes a user does not eat right away, the cooking program further provides a heat preservation process to maintain the temperature of cooked food so that when warm food can be served whenever the user needs. The temperature during the heat preservation process is controlled to be within a lower limit temperature and an upper limit temperature. When the temperature sensing assembly 80 detects that the temperature of the inner pot assembly 30 is lower than the lower limit, the control means controls the heating means 70 to operate. When the temperature sensing assembly 80 detects that the temperature of the inner pot assembly 30 is higher than the upper limit, the control means controls the heating means 70 to stop operating. Generally, the temperature of the heat preservation process is controlled to be 70-80 C.
Unless otherwise defined, technical and scientific terms used herein have the same meanings as commonly understood by a person skilled in the art of the present invention.
The terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the present invention. Terms such as "provided" may mean that one part is directly attached to another part or that one part is attached to another part through an intermediary part. A feature described herein in one embodiment may be applied to another embodiment alone or in combination with another feature, unless the feature is not applicable in the other embodiment or stated otherwise.
The present invention has been described by means of the above-described embodiments, but it should be understood that the above-described embodiments are only for the purpose of illustration and description, and are not intended to limit the present invention to the scope of the described embodiments. It will be appreciated by a person skilled in the art that various variations and modifications can be made according to the teachings of the present invention, and those variations and modifications all fall within the scope of protection claimed by the present invention.

Claims (28)

Claims

1. An inner pot assembly (30) for a cooking utensil, characterized in that, it comprises:
- an inner pot (40) having a height of [90, 200] mm; and - a steamer basket (50) supported in the inner pot (40) and removable therefrom, comprising a bottom wall (51) and a side wall (52) connected with the bottom wall (51), the bottom wall (51) and the side wall (52) enclosing an accommodating chamber for accommodating rice, the steamer basket (50) is fitted to the inner pot (40) so that a receiving space (60) is formed between the bottom wall (51) and the inner pot (40), or between the bottom wall (51), the side wall (52), and the inner pot (40), the bottom wall (51) comprising a water rising part (54), a guiding part (56) extending outward from an outer border of the water rising part (54), and a water descending part (53) extending outward from an outer border of the guiding part (56), the water rising part (54) being arranged higher than the water descending part (53), rice being accommodated on the water rising part (54), the guiding part (56) and the water descending part (53), the water rising part (54) being provided with a plurality of first through holes (57) communicating the accommodating chamber with the receiving space (60) and allowing water, but not rice, to pass through, the water descending part (53) being provided with a plurality of second through holes (58) communicating the accommodating chamber with the receiving space (60) and allowing water, but not rice, to pass through, and the guiding part (56) being a water-impermeable zone extending from the outer most borders of the first through holes (57) to the inner most borders of the second through holes (58), a maximum height difference between the water rising part (54) and the water descending part (53) being H1, and a height difference between any one of the first through holes (57) and any one of the second through holes (58) being H2, wherein, 3 mm H1 5 40 mm, and/or 3 mm H2 5 40 mm, so that during cooking, boiling water in the receiving space (60) is able to enter the accommodating chamber via the first through holes (57).

2. The inner pot assembly (30) of claim 1, characterized in that, 8 mm H1 5 30mm, and/or 8 mm H2 5 30 mm, and more preferably, 10 mm H1 5 20mm, and/or 10 mm H2 5 20 mm.

3. The inner pot assembly (30) of any one of the preceding claims, characterized in that, the area of the projection of the water rising part (54) on a horizontal plane is equal to or larger than 80 mm2, the area of the projection of the bottom wall (51) on a horizontal plane is [11000, 46000] mm2, and/or the area of the guiding part (56) is equal to or larger than 700 mm2, and/or the volume of the receiving space (60) is [200, 2000] ml..

4. The inner pot assembly (30) of any one of the preceding claims, characterized in that, the bottom wall (51) is rotationally symmetric with the central axis of the steamer basket (50) as its rotation axis.

5. The inner pot assembly (30) of claim 4, characterized in that, the guiding part (56) comprises any one of a cylindrical side face, a truncated cone side face, or an arc-shaped face, or any combination thereof.

6. The inner pot assembly (30) of claim 4, characterized in that, a top part of the guiding part (56) and a bottom part of the guiding part (56) are both horizontal planes and are connected by a revolution face in the form of a side face of a truncated cone.

7. The inner pot assembly (30) of any one of claims 4 to 6, characterized in that, the water 1(:) rising part (54) is a horizontal plane, and/or the water descending part (53) is a horizontal plane.

8. The inner pot assembly (30) of any one of claims 1 to 7, characterized in that, the steamer basket (50) is fitted to the inner pot by contact or by proximity at a location of fitting, and the distance between the steamer basket (50) and the inner pot (40) at the location of fitting is equal to or smaller than 1 mm.

9. The inner pot assembly (30) of claim 8, characterized in that, the location of fitting is not higher than the top of the water rising part (54).

10. The inner pot assembly (30) of claim 9, characterized in that, the maximum distance H3 between the location of fitting and the top of the water rising part (54) in the vertical direction is such that 1 H1/H3 15.

11. The inner pot assembly (30) of any one of claims 8 to 10, characterized in that, the side wall (51) is provided with a plurality of side wall through holes (62) provided in a spaced manner along the circumferential direction of the steamer basket (50) and located higher than the location of fitting between the steamer basket (50) and the inner pot (40).

12. The inner pot assembly (30) of any one of claims 8 to 11, characterized in that, when the steamer basket (50) is placed in the inner port (40), an inner surface of the inner pot (40) is in contact with the steamer basket (50) so that the steamer basket (50) is fitted to the inner pot (40) by contact, wherein, the inner surface of the inner pot (40) is provided with an arc-shaped structure, a bevel structure, an inward protruding structure (42), or a step structure (43) extending towards the inside of the inner pot (40), so as to come into contact with and support the steamer basket (50).

13. The inner pot assembly (30) of any one of claims 8 to 11, characterized in that, an outer surface of the steamer basket (50) is provided with a sealing member (52A) extending circumferentially that comes into contact with the inner pot (40) when the steamer basket (50) is placed in the inner pot (40), so that the steamer basket (50) is tightly fitted to the inner pot (40).

14. The inner pot assembly (30) of any one of claims 8 to 11, characterized in that, an inner surface of the inner pot (40) is provided with an inward protruding rib (44) extending circumferentially, when the steamer basket (50) is placed in the inner pot (40), the distance between the inward protruding rib (44) and an outer surface of the steamer basket (50) being smaller than or equal to 1 mm, so that the steamer basket (50) is fitted to the inner pot by proximity; or an outer surface of the side wall (52) of the steamer basket (50) is provided with an outward protruding rib extending circumferentially, when the steamer basket (50) is placed in the inner pot (40), the distance between the outward protruding rib and an inner surface of the inner pot (40) being smaller than or equal to 1 mm, so that the steamer basket (50) is fitted to the inner pot (40) by proximity.

15. The inner pot assembly (30) of any one of claims 1 to 14, characterized in that, the plurality of first through-holes (57) are uniformly distributed, and/or the plurality of second through holes (58) are uniformly distributed along the circumferential direction of the water descending part (53).

16. The inner pot assembly (30) of any one of claims 1 to 15, characterized in that, the steamer basket (50) is made of metal, wood material, or plastic material, wherein, the steamer basket (50) is integrally formed, or its bottom wall (51) is integrally formed.

17. The inner pot assembly (30) of any one of claims 1 to 16, characterized in that, the steamer basket (50) further comprises a holding part (61) extending circumferentially from the top of the side wall (51) and being depressed towards the central axis of the steamer basket (50) relative to the side wall (51).

18. The inner pot assembly (30) of any one of claims 1 to 17, characterized in that, an inner surface of the inner pot (40) is provided with at least one water level line, when the steamer basket (50) is placed in the inner pot (40), at least one water level line is lower than the second through holes (58), and/or at least one water level line is lower than the first through holes (57) but not lower than the second through holes (58).

19. The inner pot assembly (30) of claim 18, characterized in that, at least one water level line is lower than the second through holes (58) and has a height difference with the second through holes (58) which is smaller than or equal to 10 mm.

20. A cooking utensil (100), characterized in that, it comprises the inner pot assembly (30) of any one of claims 1 to 19 and heating means (70) for heating the inner pot assembly (30).

21. The cooking utensil (100) of claim 20, characterized in that, the nominal power P of the heating means (70) is such that 600W P 1500W.

22. A control method for the cooking utensil (100) of claim 20 or 21, characterized in that, the control method sequentially comprises the following processes:
- a preheating process in which the heating means (70) is controlled to heat the inner pot assembly (30) so that the temperature of the inner pot (40) rises;
- a rice rinsing and cooking process in which the heating means (70) is controlled to intermittently heat the inner pot assembly (30) so that water inside the receiving space (60) rises and enters the accommodating chamber via the first through holes (57) and the water that has entered the accommodating chamber, after soaking and rinsing rice, falls back into the receiving space (60) via the first through holes (57) and/or the second through holes (58);
- a rice steaming process in which the heating means (70) is controlled to heat the inner pot assembly (30).

23. The control method of claim 22, characterized in that, the cooking utensil (100) further comprises a temperature sensor for detecting the temperature in a cooking space, and in the preheating process, when the temperature sensor detects that the temperature inside the cooking space reaches a preset temperature T, the control method proceeds to the rice rinsing and cooking process, the preset temperature T being such that 65 C T
90 C and preferably 65 C T 80 C.

24. The control method of any one of claims 22 to 23, characterized in that, in the rice rinsing and cooking process, rice is rinsed multiple times, and during each rinsing, the heating means performs heating for a first preset duration and then stops heating for a second preset duration, when the number of times of rinsing reaches N, or when the duration of the rice rinsing and cooking process reaches a preset rinsing duration, the control method proceeds to the rice steaming process, wherein, N is a natural number.

25. The control method of claim 24, characterized in that, the heating means (70) is an electromagnetic heating element, the first preset duration is [5, 25] s, and the second present duration is [10, 35] s, wherein, N is a natural number larger than or equal to 8 but smaller than or equal to 12, and/or the preset rinsing duration is [10, 30]
minutes.

26. The control method of claim 24, characterized in that, the heating means (70) is a heating plate, the first preset duration is [7, 28] s, and the second present duration is [8, 25]

s, wherein, N is a natural number larger than or equal to 18 but smaller than or equal to 30, and/or the preset rinsing duration is [5, 15] minutes.

27. The control method according to any one of claims 22 to 26, characterized in that, the heating power during the preheating process is higher than that of the rice steaming process, and the heating power during the rice rinsing and cooking process is higher than that of the rice steaming process.

28. The control method according to any one of claims 22 to 27, characterized in that, the control method further comprises a rice braising process and when the duration of the rice steaming process reaches a preset rice steaming duration, the control method proceeds to the rice braising process, wherein, the heating power during the rice braising process is lower than that of the rice steaming process.