Heating disc and cooking utensil

Abstract

A high heat conduction area and a low heat conduction area are formed on the upper surface of the heating disc, and the high heat conduction area is used for making contact with the smooth outer surface of a pot container. The structure and / or material of the low-heat-conduction area is different from that of the high-heat-conduction area, so that the low-heat-conduction area has the temperature smaller than that of the high-heat-conduction area when the heating disc is heated, one of the high-heat-conduction area and the low-heat-conduction area forms a local area, and the other one of the high-heat-conduction area and the low-heat-conduction area forms a basic area; two adjacent local areas or an adjacent part of a single local area are arranged at intervals in at least one of the radial direction and the circumferential direction of the heating disc and divide the basic area, so that a local temperature difference area is formed on the inner surface of the pot container. Through the areas with different temperatures on the upper surface of the heating disc, a local temperature difference area is formed on the inner surface of the pot container, an obvious temperature gradient can be generated, and then liquid and food materials in the pot are boiled and rolled more sufficiently.

Description

Technical Field

[0001] The utility model relates to the technical field of kitchen appliances, in particular to a heating plate and a cooking utensil. Background Art

[0002] Current contact heating cooking utensils such as rice cookers, electric stew pots, electric pressure cookers, etc., all use a heating element that fits the pot to evenly heat the outer surface of the pot, resulting in a relatively uniform temperature inside the entire pot. Temperature difference is the basic factor for convection. The greater the local temperature difference, the more intense the convection. The inner pot with uniform temperature cannot form a large local temperature difference in the pot, so the convection generated is small, the convection area is small, and it is not intense enough. This will result in the ingredients not boiling or tumbling fully or basically not tumbling when cooking, such as cooking rice, resulting in poor cooking results.

[0003] Therefore, a heating plate and a cooking utensil are needed to at least partially solve the above problems. Utility Model Content

[0004] The content of the utility model introduces a series of simplified concepts, which will be further described in detail in the detailed implementation section. The content of the utility model does not mean to attempt to define the key features and essential technical features of the technical solution claimed for protection, nor does it mean to attempt to determine the scope of protection of the technical solution claimed for protection.

[0005] In order to at least partially solve the above problems, the utility model provides a heating plate, the upper surface of which is formed with:

[0006] A high thermal conductivity region, the high thermal conductivity region being used to contact the smooth outer surface of the pot; and

[0007] a low thermal conductivity region, the structure and / or material of the low thermal conductivity region being different from that of the high thermal conductivity region, so that the low thermal conductivity region has a temperature lower than that of the high thermal conductivity region when the heat generating disk is heated,

[0008] Among them, one of the high thermal conductivity area and the low thermal conductivity area constitutes a local area, the other of the high thermal conductivity area and the low thermal conductivity area constitutes a basic area, and two adjacent local areas or adjacent parts of a single local area itself are arranged at intervals in at least one of the radial and circumferential directions of the heating plate and divide the basic area, so that a local temperature difference area is formed on the inner surface of the pot.

[0009] According to this solution, when the cooking device is working, the upper surface of the heating plate can have areas with different temperatures, so that the heat transferred to the corresponding areas of the inner pot is different, and thus the temperature is different. As a result, a local temperature difference area is formed on the inner surface of the inner pot, which can produce a significant temperature gradient. The temperature gradient is used to make the heat convection in the pot faster and more intense, so that the liquid and ingredients in the pot boil and roll more fully, the ingredients are heated more evenly, and the cooked food tastes better.

[0010] Optionally, the heating plate has a concave surface sunken downward from the upper surface of the heating plate, and the area where the concave surface is located is the low thermal conductivity area.

[0011] According to this solution, a concave surface is set so that the concave surface does not contact the outer surface of the pot and there is a gap, so that the heating plate performs contact heat transfer in the high thermal conductivity area and non-contact heat transfer in the low thermal conductivity area. The low thermal conductivity area has a large thermal resistance and poor thermal conductivity, so a lower temperature area can be formed on the outer surface of the pot, thereby forming a local temperature difference area on the inner surface of the pot, which promotes the flow and tumbling of food and water in the pot.

[0012] Optionally, the concave surface has a depth of 0.5 mm to 5 mm.

[0013] According to this solution, the depth of the depression is moderate, which meets the requirements of the local temperature difference area formed on the inner surface of the pot, the food in the pot has sufficient tumbling force, and the energy efficiency of the heating plate heating system is moderate, avoiding the situation of undercooked food or energy waste.

[0014] Optionally, the thermal conductivity of the high thermal conductivity region is greater than the thermal conductivity of the low thermal conductivity region.

[0015] According to this solution, the upper surface of the heating plate has areas with different thermal conductivity coefficients. A temperature difference can be formed between the area with high thermal conductivity and the area with low thermal conductivity coefficient, thereby forming a local temperature difference area on the inner surface of the pot, promoting the flow and rolling of food and water in the pot.

[0016] Optionally, the heating plate includes a high thermal conductor made of a high thermal conductivity material and a low thermal conductor made of a low thermal conductivity material, the thermal conductivity of the high thermal conductivity material is greater than the thermal conductivity of the low thermal conductivity area, the upper surface of the high thermal conductor constitutes the high thermal conductivity area, and the upper surface of the low thermal conductor constitutes the low thermal conductivity area.

[0017] According to this solution, by setting the material of the heating plate, the heating plate has different thermal conductivity coefficients in different areas, and the production and manufacturing of the heating plate is simple and the manufacturing cost is low.

[0018] Optionally, the high thermal conductor and the low thermal conductor are constructed separately and combined into the heating plate.

[0019] According to this solution, two heat conductors form a heating plate, which has a simple structure and is easy to produce.

[0020] Alternatively, the heat generating plate includes a heat generating plate body, and the high thermal conductor and the low thermal conductor are formed on an upper surface of the heat generating plate body.

[0021] According to this solution, the two heat conductors and the heating plate body constitute a heating plate, which has a simple structure and is easy to produce.

[0022] Optionally, the heating plate comprises a heating plate body and a thermal insulation coating, the thermal insulation coating is formed on the upper surface of the heating plate body, the exposed portion of the upper surface of the heating plate body constitutes the high thermal conductivity area, and the upper surface of the thermal insulation coating constitutes the low thermal conductivity area.

[0023] According to this solution, a temperature difference can be formed between the area with the heat-insulating coating and the area without the heat-insulating coating on the upper surface of the heating plate, thereby forming a local temperature difference area on the inner surface of the pot, promoting the flow and tumbling of food and water in the pot.

[0024] Optionally, the upper surface of the heating plate is chemically and / or physically treated to form the high thermal conductivity region and the low thermal conductivity region with different thermal conductivities.

[0025] According to this solution, the surface properties of the upper surface of the heating plate can be changed so that the thermal conductivity coefficients of the two heat-conducting areas are different, and the structure of the heating plate is simple.

[0026] Optionally, the high thermal conductivity region accounts for 30% to 90% of the area of ​​the upper surface of the heating plate.

[0027] According to this solution, the energy requirement for normal cooking of ingredients can be guaranteed, and the overall heating effect and local convection effect can be guaranteed.

[0028] The low thermal conductivity region itself has a spacing S, wherein S is 4 mm to 80 mm.

[0029] According to this solution, the inner surface of the pot can obtain a temperature gradient within a desired range while avoiding heat shortage. The heat convection effect between the liquid and food in the pot is good, which can meet cooking needs.

[0030] The local areas are arranged in an array, an annular arrangement and / or a spiral arrangement.

[0031] According to this solution, neatly arranged local temperature difference areas can be formed, which is conducive to better controlling the thermal convection heating of the liquid and food in the pot, the thermal convection effect is better, and the food at various positions in the pot is heated more evenly.

[0032] According to another aspect of the utility model, a cooking utensil is provided, comprising a pot and a heating plate according to any one of the above aspects, wherein the heating plate is located below the pot, wherein the pot has a smooth outer surface, and the high thermal conductivity area contacts the outer surface of the pot.

[0033] According to this plan, BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The following drawings of the present invention are used as a part of the present invention for understanding the present invention. The drawings show the implementation of the present invention and its description, and are used to explain the principle of the present invention.

[0035] In the attached figure:

[0036] Figure 1 It is a cross-sectional view of a pot and an electric heating device according to an embodiment of the utility model;

[0037] Figure 2 for Figure 1 A perspective schematic diagram of a first example of a heating plate shown in FIG.

[0038] Figure 3 for Figure 2 A partial cross-sectional schematic diagram of the heating plate shown;

[0039] Figure 4 for Figure 1 A three-dimensional schematic diagram of a high thermal conductor in a second example of a heat generating plate shown in FIG.

[0040] Figure 5 for Figure 1 A three-dimensional exploded schematic diagram of a low thermal conductor in a second example of a heating plate shown in FIG.

[0041] Fig. 6A for Figure 4 and Figure 5 A partial cross-sectional schematic diagram of the heating plate shown;

[0042] Figure 6B for Fig. 6A A partial cross-sectional schematic diagram of an alternative example of a heat generating plate is shown;

[0043] Figure 7 for Figure 1 A perspective schematic diagram of a third example of a heating plate shown in FIG.

[0044] Figure 8 for Figure 7 A partial cross-sectional schematic diagram of the heating plate shown;

[0045] Fig. 9 for Figure 1 A perspective schematic diagram of a fourth example of a heating plate shown in FIG.

[0046] Fig.10 for Fig. 9 A partial cross-sectional schematic diagram of the heating plate shown;

[0047] FIG. 11A to FIG. 11C for Figure 1 A partial cross-sectional schematic diagram of the pot and the heating plate shown in FIG.

[0048] FIG. 12A to FIG. 12H for Figure 1 Top views of various examples of heating plates shown in FIG.

[0049] Description of reference numerals:

[0050] 1 Pot

[0051] 2Electric heating device

[0052] 3 heating plate

[0053] 4 heating tubes

[0054] 5 center hole

[0055] 6 Concave

[0056] 7High thermal conductivity

[0057] 8Low thermal conductivity

[0058] 9 Heating plate body

[0059] 10 Depression

[0060] 11. Thermal insulation coating

[0061] R11 high thermal conductivity area

[0062] R12 low thermal conductivity area

[0063] R21 Local Area

[0064] R22 base area DETAILED DESCRIPTION

[0065] In the following description, a large number of specific details are given to provide a more thorough understanding of the utility model. However, it is obvious to those skilled in the art that the utility model can be implemented without one or more of these details. In other examples, in order to avoid confusion with the utility model, some technical features known in the art are not described.

[0066] In order to thoroughly understand the present invention, a detailed description will be provided in the following description. Obviously, the implementation of the present invention is not limited to the specific details familiar to those skilled in the art. The preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention may also have other embodiments.

[0067] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the utility model. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of the features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0068] Ordinal numbers such as "first" and "second" cited in the present invention are merely identifiers and do not have any other meanings, such as a specific order, etc. Moreover, for example, the term "first component" itself does not imply the existence of the "second component", and the term "second component" itself does not imply the existence of the "first component".

[0069] It should be noted that the terms "upper", "lower", "front", "back", "left", "right", "inside", "outside" and similar expressions used in this document are for illustrative purposes only and are not limiting.

[0070] Now, exemplary embodiments according to the present utility model will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in a variety of different forms and should not be interpreted as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present utility model thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art.

[0071] The utility model provides a contact heating cooking utensil, which can cook food by using electric heating technology. The cooking utensil can be, for example, an electric rice cooker, an electric stew pot, an electric heating stove equipped with a pot, a pressure cooker or other cooking utensil, and the cooking utensil can have various functions such as cooking porridge in addition to cooking rice.

[0072] like Figure 1As shown, the cooking utensil comprises a pot 1 and an electric heating device 2 disposed under the pot 1. The pot 1 has a smooth outer surface. The electric heating device 2 comprises a heating plate 3 and a heating tube 4, wherein the heating plate 3 contacts the outer surface of the pot 1, and the heating tube 4 is at least partially located inside the heating plate 3. When the heating tube 4 is powered on, heat is generated to heat the surface of the heating plate 3 to a relatively high temperature, thereby heating the pot 1 in contact with the upper surface of the heating plate 3.

[0073] For a cooking appliance such as an electric rice cooker, it includes a pot body and a lid. The pot body has a cylindrical pot storage portion. The pot 1 can be fixedly arranged at the pot storage portion, or can be freely placed in or taken out of the pot storage portion to facilitate the cleaning of the pot 1. The pot 1 is usually made of metal material and has a circular opening on the upper surface for holding materials to be heated, such as rice, soup, etc. The pot body includes the above-mentioned electric heating device 2 for heating the pot 1 to heat the pot 1.

[0074] The cover has a shape that is substantially corresponding to the pot body. The cover can be opened and closed on the pot body. Specifically, it is pivotally connected to the pot body through a pivot shaft and can freely pivot between a closed position and an open position relative to the pot body around a pivot axis where the pivot shaft is located, so as to facilitate the closing and opening of the pot body. When the cover is closed on the pot body, it covers the inner pot 1 and forms a cooking space between the inner pot 1 and the inner pot 1. The cover is usually also provided with a pot mouth sealing ring, which can be made of, for example, a rubber material, and is arranged between the cover and the inner pot 1 to seal the cooking space when the cover is in the closed state.

[0075] For a cooking appliance of the electric stove type, the pot 1 and the electric stove are independent of each other, and the pot 1 can be placed on the upper surface of the electric stove when in use.

[0076] For contact heating cooking utensils, the heat transfer path is from the heating tube 4 to the upper surface of the heating plate 3, then to the outer surface of the inner pot, then to the inner surface of the inner pot, and finally to the food.

[0077] In order to make the fluid food in the pot form strong convection under the action of a large temperature difference, it is necessary to form a large temperature difference on the inner surface of the pot 1, and then to form a large temperature difference on the outer surface of the pot 1. Therefore, the utility model proposes a heating plate 3, so that a large temperature difference is formed on the upper surface of the heating plate 3, and finally a large temperature difference is formed on the inner surface of the pot 1, so as to promote strong convection tumbling of food in the pot 1.

[0078] like Figures 2 to 10As shown, a high thermal conductivity region R11 and a low thermal conductivity region R12 are formed on the upper surface of the heating plate 3. The high thermal conductivity region R11 is used to contact the smooth outer surface of the pot 1; the structure and / or material of the low thermal conductivity region R12 are different from those of the high thermal conductivity region R11, so that when the heating plate 3 is heated, the temperature of the low thermal conductivity region R12 is lower than that of the high thermal conductivity region R11. One of the high thermal conductivity region R11 and the low thermal conductivity region R12 constitutes a local region R21, and the other of the high thermal conductivity region R11 and the low thermal conductivity region R12 constitutes a base region R22. The local region R21 is arranged within the range where the base region R22 is arranged, and can divide the base region R22 into connected or unconnected regions. Two adjacent local areas R21 or the adjacent parts of a single local area R21 itself are arranged at intervals in at least one of the radial and circumferential directions of the heating plate 3 and divide the base area R22, thereby forming different temperatures in the high thermal conductivity area R11 and the low thermal conductivity area R12, so that a local temperature difference area is formed on the inner surface of the pot 1.

[0079] It should be noted that the "high" in the "high thermal conductivity region R11" and the "low" in the "low thermal conductivity region R12" are relative, that is, when comparing the two, the thermal conductivity efficiency or thermal conductivity effect of one is higher, and the thermal conductivity efficiency or thermal conductivity effect of the other is lower. It should be noted that the terms "local" in the "local region R21" and "base" in the "base region R22" have no limiting effect on their respective areas in terms of text, that is, they do not mean to limit the size of the areas of the two.

[0080] The high thermal conductivity region R11 and the low thermal conductivity region R12 are alternately arranged along the circumference of the heating disk 3, and the adjacent high thermal conductivity region R11 and low thermal conductivity region R12 are closely adjacent to each other, and there is no other region between them. Among them, the high thermal conductivity region R11 has a larger area, and the low thermal conductivity region R12 has a smaller area. A center hole 5 is provided in the middle of the heating disk 3, and the high thermal conductivity region R11 is fan-shaped, and the low thermal conductivity region R12 is also fan-shaped. Alternatively, the middle of the heating disk 3 can be a solid, that is, there is no center hole 5.

[0081] In this example, the high thermal conductivity region R11 constitutes the local region R21, and the low thermal conductivity region R12 constitutes the base region R22; it can also be said that the high thermal conductivity region R11 constitutes the base region R22, and the low thermal conductivity region R12 constitutes the local region R21. Adjacent high thermal conductivity regions R11 are arranged at intervals in the circumferential direction of the heating disk 3, and adjacent low thermal conductivity regions R12 are arranged at intervals in the circumferential direction of the heating disk 3.

[0082] With such arrangement, when the cooking appliance is working, the upper surface of the heating plate 3 can have areas with different temperatures, so that the heat transferred to the corresponding areas of the inner pot 1 is different, and thus the temperature is different. As a result, a local temperature difference area is formed on the inner surface of the inner pot 1, which can produce a significant temperature gradient. The temperature gradient is used to make the heat convection in the pot faster and more intense, so that the liquid and ingredients in the pot boil and roll more fully, the ingredients are heated more evenly, and the cooked food tastes better.

[0083] Figure 2 and Figure 3 An example of a heating plate 3 is schematically shown. Figure 2 and Figure 3 As shown, the heating plate 3 has a concave surface 6 that is sunken downward from the upper surface of the heating plate 3, and the area where the concave surface 6 is located is the low thermal conductivity area R12. The upper surface of the heating plate 3 outside the concave surface 6 is the high thermal conductivity area R11. The structure of the low thermal conductivity area R12 in this example is different from that of the high thermal conductivity area R11. By setting the concave surface 6, the concave surface 6 is not in contact with the outer surface of the pot 1, and there is a gap, so that the heating plate 3 is in contact heat transfer in the high thermal conductivity area R11 and non-contact heat transfer in the low thermal conductivity area R12. The low thermal conductivity area R12 has a large thermal resistance and poor thermal conductivity, and can form a lower temperature area on the outer surface of the pot 1, thereby forming a local temperature difference area on the inner surface of the pot 1, which promotes the flow and tumbling of food and water in the pot.

[0084] The depth of the concave surface 6 is related to the material of the heating plate 3. Optionally, the depth of the concave surface 6 can be 0.5 mm to 5 mm, for example, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm and other suitable values. Preferably, it is 1.5 mm. If the depth of the concave surface 6 is too small, the temperature difference formed will be too small, and the rolling force of the food in the pot will be insufficient; if the depth of the concave surface 6 is too large, the energy efficiency of the heating system of the heating plate 3 will be too low, resulting in the situation where the food is not cooked or energy is wasted.

[0085] Figures 4 to 8 Two different examples of the heating plate 3 are schematically shown. In these two examples, the concave surface 6 is not provided. Instead, the heating plate 3 is constructed so that its upper surface has regions with different thermal conductivity coefficients. Further, the heating plate 3 is constructed so that the thermal conductivity coefficient of the high thermal conductivity region R11 is greater than the thermal conductivity coefficient of the low thermal conductivity region R12. With such a configuration, the region with high thermal conductivity and the region with low thermal conductivity on the upper surface of the heating plate 3 can form a temperature difference, thereby forming a local temperature difference region on the inner surface of the pot 1, promoting the flow and tumbling of food and water in the pot. It should be noted that "thermal conductivity coefficient" refers to the surface thermal conductivity coefficient.

[0086] In these two examples, the heating plate 3 includes a high thermal conductor 7 made of a high thermal conductivity material and a low thermal conductor 8 made of a low thermal conductivity material. The thermal conductivity of the high thermal conductivity material is greater than the thermal conductivity of the low thermal conductivity region R12, the upper surface of the high thermal conductor 7 constitutes the high thermal conductivity region R11, and the upper surface of the low thermal conductor 8 constitutes the low thermal conductivity region R12. The high thermal conductivity region R11 and the low thermal conductivity region R12 in this example can form a roughly smooth surface, and both are in contact with the outer surface of the pot 1.

[0087] The heating plate 3 includes two materials with different thermal conductivity coefficients, one is a material with a relatively large thermal conductivity coefficient, which can be a metal or a non-metal material, such as aluminum, copper, graphite, graphene, etc., and the other is a material with a relatively small thermal conductivity coefficient, which can be a metal or a non-metal material, such as steel, ceramics, etc. By setting the material of the heating plate 3, the heating plate 3 has different thermal conductivities in different areas, and the manufacturing of the heating plate 3 is simple and the manufacturing cost is low.

[0088] It should be noted that the term "body" used herein includes a structure formed by mold molding, a block formed by a formed material such as a sheet, a layered body formed by a material such as a coating, and any other structure. Specifically, the high thermal conductor 7 includes a functional block formed by a formed material such as a sheet, a functional layer formed by a material such as a coating, or any other form of structure.

[0089] The two materials can be combined by lamination (including hot lamination, cold lamination), spraying, brazing, etc. For lamination, the low thermal conductivity material can be compounded on the basis of the high thermal conductor 7, or the high thermal conductivity material can be compounded on the basis of the low thermal conductor 8.

[0090] Figure 4 and Figure 5 An example of a heat generating plate 3 with different materials is schematically shown, in which a high thermal conductor 7 and a low thermal conductor 8 are separately constructed and combined to form the heat generating plate 3. Figure 5 Four separate low thermal conductors 8 are schematically shown. Optionally, Fig. 6A As shown, the high thermal conductor 7 serves as the main body of the heating plate 3, and the low thermal conductor 8 is compounded to the high thermal conductor 7. In this solution, the number of the high thermal conductor 7 is one, and the number of the low thermal conductor 8 is multiple. The high thermal conductor 7 has multiple recesses 10, and the low thermal conductor 8 is located in the recesses 10. Of course, the low thermal conductor 8 can also serve as the main body of the heating plate 3, and the high thermal conductor 7 is compounded to the high thermal conductor 7. In this solution, the number of the low thermal conductor 8 is one, and the number of the high thermal conductor 7 is multiple. The low thermal conductor 8 has multiple recesses 10, and the high thermal conductor 7 is located in the recesses 10. Alternatively, as Figure 6B As shown, there are multiple high thermal conductors 7 and low thermal conductors 8, which are combined into a whole with the help of auxiliary tooling.

[0091] It should be noted that the “plurality” used in this article refers to two or more.

[0092] Figure 7 and Figure 8 Another example of a heating plate 3 with different materials is schematically shown, in which the heating plate 3 includes a heating plate 3 body, a high thermal conductor 7 and a low thermal conductor 8, and the high thermal conductor 7 and the low thermal conductor 8 are formed on the upper surface of the heating plate 3 body. The heating plate 3 body is a thermal conductor, and its material can be the same as or different from that of the high thermal conductor 7.

[0093] The above example is that different materials result in different thermal conductivities of the two heat-conducting areas. Alternatively, the surface properties of the upper surface of the heating plate 3 can be changed to make the thermal conductivities of the two heat-conducting areas different. Specifically, the upper surface of the heating plate 3 is formed into a high thermal conductivity area R11 and a low thermal conductivity area R12 with different thermal conductivities by chemical and / or physical surface treatment processes. The surface treatment process includes any suitable process such as oxidation, etching, photolithography, polishing, sandblasting, etc.

[0094] An example of a treatment scheme is to oxidize a portion of the upper surface of the heating plate 3 to form aluminum oxide. The thermal conductivity of the unoxidized area is much greater than that of the oxidized area. At this time, the unoxidized area is a high thermal conductivity area R11, and the oxidized area is a low thermal conductivity area R12. In this way, different temperature areas can also be formed on the upper surface of the heating plate 3.

[0095] An example of a treatment solution is to etch a portion of the upper surface of the heating plate 3. The heat transfer resistance of the etched area increases, and the thermal conductivity of the etched area is less than that of the unetched area. At this time, the unetched area is a high thermal conductivity area R11, and the etched area is a low thermal conductivity area R12. This will also form different heat distribution areas on the inner surface of the pot 1, promoting the tumbling flow of food.

[0096] An example of a treatment scheme is to roughen a part of the upper surface of the heating plate 3 to increase the roughness of the part. The heat transfer resistance of the roughness treated area increases, and the thermal conductivity of the roughness treated area is less than that of the roughness untreated area. At this time, the roughness untreated area is a high thermal conductivity area R11, and the roughness treated area is a low thermal conductivity area R12. This will also form different heat distribution areas on the inner surface of the pot 1, promoting the tumbling flow of food.

[0097] Fig. 9 and Fig.10An example of a heating disk 3 is schematically shown. In this example, the concave surface 6 is not provided. Instead, the heating disk 3 is constructed so that its upper surface has a thermal insulation coating 11. Further, the heating disk 3 has the thermal insulation coating 11 in the low thermal conductivity region R12. Specifically, the heating disk 3 includes a heating disk 3 body and a thermal insulation coating 11. The thermal insulation coating 11 is formed on the upper surface of the heating disk 3 body, and the exposed portion of the upper surface of the heating disk 3 body constitutes the high thermal conductivity region R11, and the upper surface of the thermal insulation coating 11 constitutes the low thermal conductivity region R12.

[0098] With such arrangement, the heat generated from the heating tube 4 is blocked by the heat-insulating coating 11 through the main body of the heating plate 3, so that it cannot be transmitted to the surface of the heating plate 3; thereby, a temperature difference can be formed between the area with the heat-insulating coating 11 and the area without the heat-insulating coating 11 on the upper surface of the heating plate 3, thereby forming a local temperature difference area on the inner surface of the pot 1, which promotes the flow and rolling of food and water in the pot.

[0099] The heat-insulating coating 11 cannot be too thick to avoid a gap between the high heat-conducting region R11 of the heating plate 3 and the inner pot 1, which would affect the heat conduction. Optionally, the thickness of the heat-insulating coating 11 can be less than or equal to 0.5 mm, for example, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, or other suitable values.

[0100] Optionally, the material of the heat insulating coating 11 may be PTFE (Polytetrafluoroethylene), PFA (Polyfluoroalkoxy), ceramics, etc. The heat insulating material may be applied to a part of the upper surface of the heating plate 3 body.

[0101] In order to form a desired temperature gradient on the inner pot, the low thermal conductivity region R12 itself has a spacing S (such as FIG. 11A to FIG. 11C As shown), the spacing S needs to maintain a certain distance requirement.

[0102] Since the heat is transferred from the outer surface of the pot 1 to the inner surface of the pot 1 by heat conduction, according to the Fourier heat conduction formula:

[0103] q=λ×△T / d (1)

[0104] In formula (1), q is the heat flux density of the pot 1 (w / m 2 ), λ is the thermal conductivity of the inner pot 1 [w / (m·k)], △T is the temperature difference formed by heat transfer in the thickness direction of the inner pot 1 (k); d is the thickness of the inner pot 1 (m), and the above formula (1) is transformed to obtain:

[0105]

[0106] From the above formula (2), it can be seen that if the lateral temperature difference of the inner surface of the inner pot 1 is increased, that is, the temperature difference between the highest point and the lowest point in the adjacent area at the same height of the inner pot 1, the heat transfer distance needs to be increased if the power and material remain unchanged.

[0107] like FIG. 11A to FIG. 11C As shown, a temperature point T1 is selected on the outer surface of the pot 1, where the temperature point T1 corresponds to the boundary between the low thermal conductivity area R12 and the high thermal conductivity area R11; two temperature points T2 and T3 are selected on the inner surface of the pot 1, where the temperature point T2 corresponds to the position of the temperature point T1 in the thickness direction, which is the highest temperature point mentioned above, and the temperature point T3 corresponds to the center position of the spacing S of the low thermal conductivity area R12, which is the lowest temperature point mentioned above. Therefore, the maximum temperature difference ΔT = T2-T3. The heat transfer distance from the temperature point T1 to T2 is L1, and the heat transfer distance from the temperature point T1 to T3 is L2, where L1 = d.

[0108] Since the metal pot 1 is generally thinner, usually not exceeding 5 mm, L2 can be approximately equal to the spacing S.

[0109] The formula for the maximum temperature difference ΔT is

[0110]

[0111] According to Fourier's law, there should be a certain temperature difference between T2 and T3. According to experimental tests, the maximum temperature difference △T at the same height of the pot 1 is most suitable in the range of 15℃~30℃. At this time, convection is enhanced while the bottom ingredients in the pot 1 will not be uncooked due to excessive temperature difference.

[0112] Substituting the range of △T into formula (3), we get:

[0113]

[0114] Right now

[0115]

[0116] Since the common thickness of the inner pot 1 is 3mm to 10mm, and the rated heating power of the heating plate 3 is about 200 to 1500W, and the thermal conductivity of non-metallic materials is about 1 to 10, and the thermal conductivity of metal materials is about 50 to 200. According to the thickness of the inner pot 1, the spacing S of the low thermal conductivity area R12 can be greater than or equal to about 4mm to 30mm. At the same time, in order to avoid the low temperature point temperature being too low to make the food cooked, the spacing S should generally not be greater than 80mm; therefore, the spacing S can be 4mm to 80mm, for example, the spacing S is 4mm, 10mm, 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm and other suitable values. Preferably, the spacing S is 10mm to 30mm. Reasonably set the spacing S, so that the inner surface of the inner pot 1 can obtain a temperature gradient within the desired range without insufficient heat, and the thermal convection effect of the liquid and ingredients in the pot is good, which can meet the cooking needs.

[0117] The setting area of ​​the high thermal conductivity region R11 also needs to be at the desired level. The area of ​​the high thermal conductivity region R11 in the upper surface of the heating plate 3 accounts for 30% to 90%. For example, the area can account for 30%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 90% and other appropriate proportions. Preferably, the area accounts for 40% to 70%. Such a setting can ensure the energy demand for normal cooking of ingredients, and ensure the overall heating effect and local convection effect. If the area of ​​the high thermal conductivity region R11 accounts for too large a proportion, the reduction in temperature difference will not achieve the effect of large-scale tumbling. If the area of ​​the high thermal conductivity region R11 accounts for too small a proportion, the thermal efficiency is low and the cooking time is prolonged.

[0118] The arrangement shape of the local area R21 is not limited, such as FIG. 12A to FIG. 12H As shown, the local area R21 can be arranged in an array, an annular arrangement and / or a spiral arrangement. Thus, neatly arranged local temperature difference areas can be formed, which is conducive to better control of the thermal convection heating of the liquid and food in the pot, the thermal convection effect is better, and the food at various positions in the pot is heated more evenly.

[0119] Fig. 12A and Fig. 12B The arrangement shape of the local area R21 in the base area is roughly the same, and the local area R21 is arranged in an array and an annular arrangement. The local area R21 includes a circular part located in the center, an arc part extending in the circumferential direction and arranged in an annular array, and an annular part located at the outermost periphery; the base area R22 includes a straight section part extending in the radial direction and an annular part. The difference is that Fig. 12A The local area R21 in the figure is the low thermal conductivity area R12, and the base area R22 is the high thermal conductivity area R11; Fig. 12BThe local area R21 in the heat conduction region R11 is the high heat conduction region, and the base area R22 is the low heat conduction region R12. According to this scheme, two adjacent local areas R21 (including circular parts, arc parts and annular parts) are arranged at intervals in the radial direction of the heating disk 3, and adjacent arc parts are arranged at intervals in the circumferential direction of the heating disk 3.

[0120] Similarly, in Fig. 12C and Fig.12D In this arrangement, the local area R21 is arranged in a ring array. The local area R21 includes a fan blade portion arranged in a ring array, and the base area R22 includes a circular portion located in the center and a fan blade portion extending radially and arranged in a ring array. The arrangement of the low thermal conductivity area R12 and the high thermal conductivity area R11 is Fig. 12C and Fig.12D According to this solution, two adjacent fan blade parts are arranged at intervals in the circumferential direction of the heating disk 3. Optionally, the blade edges of the fan blade parts are arc-shaped.

[0121] Similarly, in Fig.12E and Fig.12F In this arrangement, the local area R21 is arranged in a ring array. The local area R21 includes a circular portion and an elliptical portion arranged in a ring array, and the base area R22 is a special-shaped portion divided by the local area R21. Fig.12E and Fig.12F According to this scheme, two adjacent local areas R21 (including a circular part and an elliptical part) are arranged at intervals in the radial and circumferential directions of the heating plate 3. Optionally, the elliptical part is located radially outside the circular part and corresponds to the position between adjacent circular parts.

[0122] Similarly, in Figure 12G and Fig.12H In this arrangement, the local area R21 is arranged in a spiral shape. The local area R21 is a spiral arranged from the center to the periphery, and the base area R22 includes a spiral portion divided by the local area R21. The arrangement of the low thermal conductivity area R12 and the high thermal conductivity area R11 is Figure 12G and Fig.12H According to this scheme, the adjacent parts of the single local area R21 are arranged at intervals in the radial direction of the heating disk 3 and divide the base area R22. And the indirect D of the local area R21 gradually increases from the center to the periphery.

[0123] FIG. 12A to FIG. 12H The various arrangements of the heating discs shown, alternatively, may have a central hole 5 in the middle of these heating discs.

[0124] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein are only for describing specific implementation purposes and are not intended to limit the present invention. The features described herein in one embodiment may be applied to another embodiment alone or in combination with other features, unless the feature is not applicable or otherwise specified in the other embodiment.

[0125] The present invention has been described through the above-mentioned embodiments, but it should be understood that the above-mentioned embodiments are only for the purpose of example and explanation, and the present invention is not limited to the above-mentioned embodiments. According to the teachings of the present invention, more variations and modifications can be made, and these variations and modifications all fall within the scope of protection required by the present invention.

Claims

1. A heating plate, characterized in that: The upper surface of the heating plate is formed with: A high thermal conductivity region, wherein the high thermal conductivity region is used to contact the smooth outer surface of the pot; as well as a low thermal conductivity region, the structure and / or material of the low thermal conductivity region being different from that of the high thermal conductivity region, so that the low thermal conductivity region has a temperature lower than that of the high thermal conductivity region when the heat generating disk is heated, Among them, one of the high thermal conductivity area and the low thermal conductivity area constitutes a local area, the other of the high thermal conductivity area and the low thermal conductivity area constitutes a basic area, and two adjacent local areas or adjacent parts of a single local area itself are arranged at intervals in at least one of the radial and circumferential directions of the heating plate and divide the basic area, so that a local temperature difference area is formed on the inner surface of the pot.

2. The heating plate according to claim 1, characterized in that: The heating plate has a concave surface that is sunken downward from the upper surface of the heating plate, and the area where the concave surface is located is the low thermal conductivity area.

3. The heating plate according to claim 2, characterized in that: The concave surface has a depth of 0.5 mm to 5 mm.

4. The heating plate according to claim 1, characterized in that: The thermal conductivity of the high thermal conductivity region is greater than the thermal conductivity of the low thermal conductivity region.

5. The heating plate according to claim 1, characterized in that: The heating plate includes a high thermal conductor made of a high thermal conductivity material and a low thermal conductor made of a low thermal conductivity material. The thermal conductivity of the high thermal conductivity material is greater than the thermal conductivity of the low thermal conductivity area. The upper surface of the high thermal conductor constitutes the high thermal conductivity area, and the upper surface of the low thermal conductor constitutes the low thermal conductivity area.

6. The heating plate according to claim 5, characterized in that: The high thermal conductor and the low thermal conductor are separately constructed and combined into the heating plate; and / or The heating plate comprises a heating plate body, and the high thermal conductor and the low thermal conductor are formed on an upper surface of the heating plate body.

7. The heating plate according to claim 1, characterized in that: The heating plate comprises a heating plate body and a thermal insulation coating, wherein the thermal insulation coating is formed on the upper surface of the heating plate body, the exposed portion of the upper surface of the heating plate body constitutes the high thermal conductivity area, and the upper surface of the thermal insulation coating constitutes the low thermal conductivity area.

8. The heating plate according to claim 1, characterized in that: The upper surface of the heat generating plate is chemically and / or physically treated to form the high thermal conductivity region and the low thermal conductivity region having different thermal conductivities.

9. The heating plate according to any one of claims 1 to 8, characterized in that: The high thermal conductivity region accounts for 30% to 90% of the area of ​​the upper surface of the heating plate; and / or The low thermal conductivity area itself has a spacing S, wherein S is 4 mm to 80 mm; and / or The local areas are arranged in an array, an annular arrangement and / or a spiral arrangement.

10. A cooking utensil, characterized in that: The cooking utensil comprises a pot and a heating plate according to any one of claims 1 to 9, wherein the heating plate is located below the pot, wherein the pot has a smooth outer surface, and the high heat conductive area contacts the outer surface of the pot.

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