Electric kettle

Abstract

The electric kettle comprises an inner container body containing liquid and a heat conduction plate arranged on the outer side of the inner container body, the inner container body comprises a first arc-shaped wall extending upwards and outwards in a protruding mode from the bottom, and the heat conduction plate comprises a second arc-shaped wall extending along the first arc-shaped wall. The lower edge of the second arc-shaped wall extends towards the center of the bottom of the inner container body to form the second transverse wall, the second transverse wall is provided with a dry-burning-resistant temperature sensing element, the equivalent diameter of the second transverse wall is not larger than 50% of the equivalent diameter of the top end of the first arc-shaped wall, the heating piece is arranged on the second arc-shaped wall, the height of the first arc-shaped wall is H, and the height of the second arc-shaped wall is H. The height H1 of the lower edge of the heating piece is larger than or equal to 0.05 H and smaller than or equal to 0.2 H. The height H2 of the second arc-shaped wall is larger than or equal to 0.25 H and smaller than or equal to 0.5 H. Under the condition of different inner containers, the condition that the electric kettle does not jump early or jump late after dry burning due to the arrangement positions of the heating piece and the heat conducting plate is ensured to reach 100%.

Description

Technical Field

[0001] The invention relates to the field of household appliances, and in particular to an electric kettle. Background Art

[0002] Research has found that when the heating element is arranged on the spherical surface of the inner tank, there is a noise reduction effect. For example, the applicant disclosed a liquid heater in the patent document with application number CN202222997552.7, and its specific scheme for achieving noise reduction is: the inner surface of the bottom wall of the inner tank includes a spherical surface, and the heating element is arranged on the spherical surface. The buoyancy of the bubbles and the viscosity of the slope surface are used to make the bubbles slide from bottom to top along the slope surface, and then the small bubbles on the slope surface are merged into large bubbles, thereby reducing the small bubbles from breaking away from the bottom wall of the pot and entering the water. After the large bubbles break away from the bottom wall of the pot, it is more difficult to break in the water, thereby solving the problem of small and dense local bubbles and achieving a significant noise reduction effect.

[0003] The above technical solution can reduce noise and facilitate cleaning. However, in actual practice, if the inner and outer surfaces of the inner tank are made into spherical surfaces, such as the cup body shape disclosed in Patent No. CN201120307947.9, the cup body is used for a soymilk machine cup body. The soymilk machine cup body uses a thermostat attached to the heating element to achieve temperature sensing. This is not suitable for an electric kettle, because an electric kettle generally has a connector with a temperature-sensitive metal sheet on the outside of the inner tank or a temperature-sensitive metal sheet to detect the temperature of the inner tank and prevent dry burning. The temperature-sensitive metal sheets on the market are generally flat, which are not compatible with the spherical outer surface of the inner tank, making it difficult to achieve a good fit and sensing.

[0004] Therefore, in order to achieve noise reduction by setting the heating element on the spherical surface and match the installation of existing temperature-sensitive metal sheets on the market, it was found that in the field of soymilk machine technology, patent No. CN201020559732.1 discloses a cup body structure, in which the bottom of the cup protrudes outward and is formed into a transition connection between an arc surface and a circular plane, and the longitudinal cross-section consists of two symmetrical curves and a straight line, wherein the circular plane at the center of the bottom of the cup body occupies a proportion of the radial width of the entire bottom wall of the cup body (the sum of the radial widths of the arc surface and the circular plane) that is greater than or equal to 50%. In addition, there are also electric kettles in the prior art that refer to the cup body of the above-mentioned soymilk maker. In order to achieve even smaller improvements over existing flat-bottomed heated electric kettles in order to achieve a noise reduction effect, the bottom wall 2 of the kettle includes an outer ring portion 22 whose top surface is a sloped surface that causes small bubbles to merge into large bubbles. The sloped surface can be an inclined plane, an arc inclined surface or an irregular curved surface. It is particularly emphasized that the ratio of the diameter of the circular plane to the radial width of the entire bottom wall of the kettle is not less than 0.5 and less than 0.9. For example: the outer diameter of the bottom wall of the kettle is 140 mm, and the ratio of the radial width of the circular plane to the horizontal projection of the circular arc surface is 2.5, that is, the ratio of the diameter of the circular plane to the radial width of the entire bottom wall of the kettle is 5:7, which increases the size of the circular plane.

[0005] Although the application of the above cup body to the electric kettle reduces the difficulty of cleaning and improves the noise reduction effect to a certain extent compared with the flat bottom heating method, the study found that when the size of the circular plane increases, in order to achieve the noise reduction effect, the arc surface connecting the side wall of the inner tank and the circular plane becomes steeper, and the corner at the connection between the circular plane and the arc surface becomes sharper. On the one hand, when consumers use the commonly used scouring pad to clean the inner tank, cleaning is more inconvenient. On the other hand, the inner surface of the inner tank is not smooth enough, making it difficult for consumers to visually feel like a sphere, which is not beautiful. Then, in order to make the inner surface of the inner tank more beautiful and easy to clean, while taking into account the noise reduction effect, the plane of the inner side of the inner tank needs to be set to at least less than 50% or even set to a spherical bottom, a heat conducting plate is provided on the outer side of the inner tank, and the temperature-sensitive metal parts are installed on the heat conducting plate. In order to improve the heat transfer effect, the shape of the heat conducting plate needs to fit the shape design of the inner tank, and the proportion of the transverse wall of the heat conducting plate used to install the connector or the temperature-sensitive metal sheet also needs to be designed to be less than 50%.

[0006] Under the above-mentioned liner component shape design, the study found that the position of the heat conducting plate on the arc surface and the position of the heating tube on the arc surface greatly affect the probability of stable tripping of the temperature-sensitive metal sheet during dry burning. In view of this, it is urgent to find the optimal setting position of the heat conducting plate and the heating element. When the requirements are met, the noise reduction effect and the stable tripping consistency during mass production of the machine are the best to ensure the safety of the product. Summary of the invention

[0007] Although the prior art discloses a method of suppressing noise by setting a central plane and an arc-shaped inclined plane surrounding the central plane on the inner surface of the inner pot, it only considers that the heating element set on the arc-shaped inclined plane has a noise reduction effect, and does not find the influence of the position of the heating element and the heat conduction plate on the stable tripping probability of the temperature-sensitive metal sheet during the dry burning test, resulting in the inability to achieve the purposes of noise reduction and dry burning safety tripping at the same time.

[0008] In order to achieve the purpose of the present invention, the technical solution adopted by the present invention is as follows: an electric kettle, comprising an inner pot body for holding liquid and a heat conducting plate arranged on the outside of the inner pot body, the inner pot body comprising a first arcuate wall extending upward and outward from the bottom, the heat conducting plate comprising a second arcuate wall extending along the first arcuate wall, and a second transverse wall extending from the lower edge of the second arcuate wall toward the bottom center of the inner pot body, the second transverse wall is provided with a temperature sensing element for preventing dry burning, the equivalent diameter of the second transverse wall is not greater than 50% of the equivalent diameter of the top end of the first arcuate wall, the heating element is arranged on the second arcuate wall, the height of the first arcuate wall is H, the height of the lower edge of the heating element is H1, 0.05H≤H1≤0.2H, the height of the second arcuate wall is H2, 0.25H≤H2≤0.5H.

[0009] Furthermore, the height of the upper edge of the heating element is lower than the height of the second arc-shaped wall.

[0010] Furthermore, the inner container body includes a first transverse wall extending from the lower edge of the first arc-shaped wall toward the center of the bottom, and the second transverse wall extends along the first transverse wall.

[0011] Furthermore, the inner liner body includes a first inner liner body integrally formed with the upper edge of the first arc-shaped wall, and a second inner liner body connected to the first inner liner body by welding.

[0012] Furthermore, a ratio of an equivalent diameter of the first transverse wall to an equivalent diameter of an upper edge of the first arc-shaped wall is 0.14-0.42.

[0013] Furthermore, the second transverse wall is not smaller than the first transverse wall.

[0014] Furthermore, the equivalent diameter of the first transverse wall is d, the equivalent diameter of the inner container body at the top end of the first arc-shaped wall is D, and H is greater than d and less than 0.5D.

[0015] Furthermore, the temperature sensing element forms a temperature sensing zone, and the outer wall distance between the outer edge of the temperature sensing zone and the lower edge of the heating tube is less than 19 mm and greater than 14 mm.

[0016] Furthermore, it comprises a kettle body and a separately arranged power base, the kettle body and the power base are connected via upper and lower connectors, the temperature-sensitive metal sheet is arranged on the upper connector, and the upper connector is installed on the second transverse wall.

[0017] Furthermore, the heating element is a non-enclosed heating tube with an opening, and the heating tube is wound around the second arc-shaped wall.

[0018] Beneficial effects of the present invention:

[0019] 1. Under the condition that the curve design is aesthetically pleasing, the equivalent radius of the second transverse wall is not greater than 50% of the equivalent radius of the top of the first arc-shaped wall, and the curved surface (first arc-shaped wall) that enhances the aesthetics of the interior of the inner pot body is optimized by optimizing the positions of the heating element and the heat conducting plate. The height of the upper edge of the heating element is lower than the height of the second arc-shaped wall. The height of the first arc-shaped wall is H, the height of the lower edge of the heating element is H1, 0.05H≤H1≤0.2H, and the height of the second arc-shaped wall is H2, 0.25H≤H2≤0.5H. This ensures that in the case of different inner pots, the positions of the heating element and the heat conducting plate ensure that the probability of the electric kettle neither jumping early nor jumping late due to dry burning reaches 100%.

[0020] 2. The inner body of the electric kettle of the present application comprises a first transverse wall in the center and a first arc-shaped wall extending upward and convexly around the first transverse wall. A heating element is arranged at a position corresponding to the first arc-shaped wall in the inner shell. By arranging the convex first arc-shaped wall in the inner shell and arranging the heating element on the outer side of the first arc-shaped wall, the temperature at the first arc-shaped wall is higher, and it is easier to generate bubbles on the first arc-shaped wall. When the bubbles move along the first arc-shaped wall, small bubbles will converge into large bubbles, thereby increasing the volume of the bubbles and reducing the frequency of bubble rupture, which can effectively reduce the noise generated when the electric kettle boils water. At the same time, the present application controls the ratio of the equivalent diameter of the first transverse wall in the center of the inner shell to the upper edge of the first arc-shaped wall to be between 0.14 and 0.42. By reasonably designing the size of the first transverse wall in the center, the heating speed can be taken into account while reducing the noise, thereby ensuring that the electric kettle has a lower noise and a faster boiling speed, thereby satisfying the user's use experience.

[0021] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0023] Figure 1 It is a structural schematic diagram of the electric kettle of the present application.

[0024] Figure 2 It is a schematic diagram of the structure of the inner container of the electric kettle of the present application.

[0025] Figure 3 It is a schematic diagram of the assembly of the inner tank of the electric kettle of the present application.

[0026] Figure 4 It is a noise and heating rate diagram at different equivalent diameter ratios of Example 5 of the present application.

[0027] Figure 5 This is a diagram of noise and heating rate at different equivalent diameter ratios of Example 6 of the present application.

[0028] Figure 6 This is a diagram of noise and heating rate at different equivalent diameter ratios of Example 7 of the present application.

[0029] Figure 7 This is a diagram of the dry burning tripping situation at different height ratios of Example 8 of the present application.

[0030] Figure 8 This is a diagram of the dry-burning tripping situation at different height ratios of Example 1 of the present application.

[0031] Fig. 9 This is a diagram of the dry burning tripping situation at different height ratios of Example 2 of the present application.

[0032] Fig.10 This is a diagram of the dry-burning tripping situation at different height ratios of Example 3 of the present application.

[0033] Fig.11 This is a diagram of the dry-burning tripping situation at different height ratios of Example 4 of the present application.

[0034] Description of the drawings: 1. Outer shell; 2. Inner liner; 201. Inner liner bottom; 202. Inner liner body; 2021. Second inner liner body; 2022. First inner liner body; 21. Inner liner body; 211. First curved wall; 212. First transverse wall; 22. Heat conducting plate; 221. Second curved wall; 222. Second transverse wall; 3. Heating element. DETAILED DESCRIPTION

[0035] To make the purpose, technical solution and advantages of the present invention more clear, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other arbitrarily without conflict.

[0036] The electric kettle is also known as a water boiler, a health kettle, a milk mixer, etc. It has a water boiling function and includes a kettle body and a separately arranged power base. The kettle body includes an inner liner body 21 for holding liquid and a heat conducting plate 22 attached to the outer side of the inner liner body 21. Alternatively, it can be understood as follows: the kettle body includes an inner liner assembly, and the inner liner assembly includes an inner liner body 21, a heat conducting plate 22, and a heating element 3. The outer side of the inner liner body 21 may or may not be provided with an outer shell, and the connector is provided below the inner liner assembly. In the actual application process of the inner liner body 21, the inner liner cup body includes a kettle body and a chassis. One is that the kettle body and the chassis are directly integrally formed, and the other is that the kettle body and the chassis are connected to form a receiving cavity for holding liquid. At this time, the heat conducting plate 22 is attached to the outer side of the chassis. Furthermore, the heat conducting plate 22 and the chassis can be connected by welding. In order to improve the heat transfer efficiency between the heat conducting plate 22 and the chassis and reduce the noise caused by poor welding, the heat conducting plate 22 and the chassis can also be formed into a composite metal plate by die casting or injection molding.

[0037] In order to heat water faster, the existing electric kettle generally uses a heating element 3 with a power between 1500W and 2000W according to the capacity. For example, 1500W is used for a volume of 1.5L, and 1800W is used for a volume of 1.7L. The faster boiling speed causes a large number of bubbles to be generated on the inner surface of the inner pot. The noise generated by the bursting of the bubbles is relatively large, up to 70 decibels, which greatly affects the user experience. Although the prior art discloses a method of suppressing noise by setting a center plane and an arc-shaped inclined plane surrounding the center plane on the inner surface of the inner pot, it only considers that the heating element 3 is set on the arc-shaped inclined plane to have a noise reduction effect, and does not find the influence of the position of the heating element 3 and the heat conducting plate 22 on the stable tripping probability of the temperature-sensitive metal sheet during the dry-burning test, resulting in the inability to achieve the purpose of noise reduction and dry-burning safety tripping at the same time.

[0038] In order to be compatible with the noise reduction and dry-burning safety tripping issues, the electric kettle is guaranteed to have a long service life and meet the user's usage experience, such as Figure 1-3 As shown, the present invention provides an electric kettle, comprising an inner pot body 21 for containing liquid and a heat conducting plate 22 attached to the outer side of the inner pot body 21, wherein the inner pot body 21 comprises a first arcuate wall 211 extending upward and outward from the bottom, and the heat conducting plate 22 comprises a second arcuate wall 221 extending along the first arcuate wall 211, and a second transverse wall 222 extending from the lower edge of the second arcuate wall 221 toward the bottom center of the inner pot body 21, at this time, a connector with a temperature-sensitive metal sheet is arranged on the second transverse wall 222, and the temperature-sensitive metal sheet is used to prevent dry burning, and the temperature-sensitive metal sheet is a mechanical movement The heating element 3 is arranged on the second curved wall 221, the equivalent radius of the second transverse wall 222 is not greater than 50% of the equivalent radius of the top of the first curved wall 211, and the curved surface (first curved wall 211) that enhances the aesthetics of the interior of the inner pot body 21, the height of the upper edge of the heating element 3 is lower than the height of the second curved wall 221, the height of the first curved wall 211 is H, the height of the lower edge of the heating element 3 is H1, 0.05H≤H1≤0.2H, the height of the second curved wall 221 is H2, 0.25H≤H2≤0.5H. For example, the height H1 of the lower edge of the heating element 3 is the longitudinal distance from the lowest point of the contact surface between the heating element 3 and the heat conducting plate 22 to the center of the bottom of the inner pot.

[0039] Specifically, the first arcuate wall 211 of the liner body 21 can extend upward and outward from the center of the liner, and at this time, the bottom of the liner body 21 is spherical, or, in order to make the second transverse wall 222 fit more closely with the liner body 21, especially to reduce the possibility of cold welding during welding and improve heating uniformity, the liner body 21 includes the first arcuate wall 211 and the first transverse wall 212 extending from the lower edge of the first arcuate wall 211 to the bottom center, and when the liner body 21 includes the first transverse wall 212, the second transverse wall 222 extends along the first transverse wall 212. The curvatures on the first arcuate wall 211 can be the same or different.

[0040] The heating element 3 in the present application generally adopts an aluminum heating tube with a resistance wire. Preferably, the heating element 3 is a non-enclosed heating tube with an opening, and the heating tube is wound on the second arc-shaped wall 221, wherein the temperature sensing area of ​​the temperature sensing element is located on the side facing the opening. Of course, the heating element 3 can also be a closed heating tube.

[0041] In the embodiment of the present invention, in order to better adapt to the shape of heating tubes on the market, preferably, a non-enclosed heating tube with an opening is used, and the heating tube is wound around the second arc-shaped wall 221 in a single circle. Based on the shape of the above heating tube, the present invention can reduce noise while achieving dry-burning safety test by reasonably setting the longitudinal position of the upper edge of the heating element 3 and the heat conducting plate 22 on the first arc-shaped wall 211.

[0042] It can be understood by those skilled in the art that when the heating element 3 of the same power is manufactured, it has variability according to the process conditions and cost requirements. For example, in one case, the heating element 3 can be wound on the second curved wall 221 in a single circle, and in the other case, multiple circles can be wound side by side on the second curved wall 221. The contact areas between the heating element 3 and the second curved wall 221 of the two installation methods can be the same or different. Without considering other factors, when the contact areas are different, the larger the contact area, the higher the heating efficiency. When the contact areas are the same, the heating efficiency is generally the same.

[0043] Therefore, the technology in this field can easily think of setting the heating element 3 at the uppermost end (top end) of the first curved wall 211, that is, the larger the ratio of the height of the second curved wall 221 to the height of the first curved wall 211, the better. In this way, the installation contact area of ​​the heating element 3 and the second curved wall 221 can be larger, which can improve the heating efficiency. Although the installation contact area of ​​the heating element 3 and the second curved wall 221 is increased, it also brings about the problem of the service life of the inner tank component when boiling water. During the use of the electric kettle, the user may have the need to boil water in a small amount of water or directly boil water in a small amount of water by pouring water in stages. When the inner tank is used, the user may have the need to boil water in a small amount of water or directly boil water in a small amount of water. When the water level in the tank body 21 is lower than the position of the heating element 3, the thermal conductivity at the position of the heating element 3 is reduced and the temperature rises quickly. The higher the position of the heating element 3 is, the longer the high heat at the position of the heating element 3 lasts. Such a continuous high temperature situation will accelerate the breakage of the resistance wire in the heating tube, shorten the life of the whole machine, and even cause the heat conduction plate 22 and the inner tank body 21 to split; even if the resistance wire is not broken, the inner side of the inner tank body 21 continues to burn empty, which will also aggravate the blackening phenomenon of the inner surface of the inner tank body 21, greatly reducing the user experience, and the user experience is one of the important evaluation criteria for the quality of the product.

[0044] On the other hand, for the stability of the product structure and to ensure the service life of the electric kettle, during the dry-burning test, it is also necessary to ensure that the temperature-sensitive metal sheet arranged on the second transverse wall 222 can trip within the specified time, or in other words, there is no abnormal phenomenon when meeting a large number of dry-burning tests. For example, during the dry-burning test, under the rated voltage, the steel pot is equipped with a dry-burning thermostat and installed on a special tooling. Each time the power is turned on and heated until the dry-burning thermostat is activated (the required tripping time for the general electric kettle is 15 to 25 seconds), the power is turned off and the water spraying time is t1 (such as 15s for a water spray volume of 500ml±20ml), and the water pouring time is t2 (such as 7s) until the tooling automatically resets as one cycle, and N (such as 500 times) cycles are performed continuously; after the test, check whether the heating plate has abnormal phenomena such as cracking and deformation, or whether there are any defects in safety performance. When the heating element 3 is set higher, the heat generated by the heating element 3 is transferred to the second transverse wall 222 through the second arc-shaped wall 221 more slowly, so that the temperature-sensitive metal sheet needs to trip for a longer time, which reflects that the time of the inner pot body 21 being dry-burned becomes longer, further reducing the service life of the inner pot body 21, the heating tube and other components. Therefore, when the height H1 of the lower edge of the heating element 3 is greater than 0.2H, that is, after the heating tube is moved up, it will not be able to effectively trip during dry-burning, that is, the probability of late tripping increases, which affects the service life of the inner pot assembly and also poses a safety problem when used by the user, which is not conducive to improving the user experience. Therefore, although the problem of dry-boiling tripping can be solved by moving the lower edge of the heating tube closer to the second transverse wall 222, the closer the lower edge of the heating element 3 is to the second transverse wall 222, that is, when the height H1 of the lower edge of the heating element 3 is less than 0.05H, first, as the heating element 3 is getting closer and closer to the temperature-sensitive metal sheet, the temperature received by the temperature-sensitive metal sheet is higher when boiling water, and the probability of early tripping of boiling water increases. Although the temperature sensing temperature of the temperature-sensitive metal sheet can be increased to solve the problem of early tripping, increasing the tripping temperature of the temperature-sensitive metal sheet will increase the probability of late tripping during dry-boiling, that is, the time from power-on to the action of the temperature-sensitive metal sheet becomes longer, affecting the user's safety; second, the inclination angle of the heating element 3 becomes smaller and smaller, and the curvature of the first arc-shaped wall 211 corresponding to the heating area is small. When the inner pot body 21 has the first transverse wall 212, the heat is quickly transferred to the first transverse wall 212, and the probability of bubbles generated on the first transverse wall 212 increases, resulting in the problem of increased noise, which also affects the user experience.

[0045] Due to the arrangement of the lower edge of the above-mentioned heating element 3, in order to ensure the process feasibility of the heating element 3, when the upper edge of the heating element 3 is flush with the second curved wall 221, the heating element 3 cannot infinitely extend the contact surface with the second curved wall 221. Therefore, in order to enhance the uniformity of heating, the upper edge of the second curved wall 221 can extend upward relative to the upper edge of the heating element 3, that is, the height of the upper edge of the heating element 3 is lower than the height of the second curved wall 221. At this time, the heat generated by the heating element 3 can be transferred from both sides of the heating element 3. However, when the upper edge of the second curved wall 221 is too far away from the upper edge of the heating element 3 (H2 is greater than 0.5H), the heat transfer plate 22 shares too much heat transferred upward, which also affects the tripping time of the temperature-sensitive metal sheet, which easily leads to the problem that the electric kettle cannot trip in time when it is dry-burned, affecting the safety performance of the product. On the other hand, when the outer shell is set on the outside of the inner tank, the closer the heat transfer plate 22 is to the outer shell, the service life of the outer shell is affected, such as causing deformation, shrinkage, melting, etc. of the outer shell. When the height H2 of the second curved wall 221 is less than 0.25H, the contact area between the heating element 3 and the second curved wall 221 will be greatly reduced, the heating uniformity will be reduced, and the noise will be further increased. It is also not conducive to the installation of the heating tube on the second curved wall 221 and the molding of the heating tube.

[0046] Figure 8-11 The horizontal axis in the table represents the ratio of H1 / H, and the vertical axis represents H2 / H. The intersection of the horizontal axis and the vertical axis in the table is determined by the position of the heating element 3 and the heat conducting plate 22 on the cup body. The symbol represents:

[0047] 2 is characterized by: when dry-burning, the dry-burning tripping time of the temperature-sensitive metal sheet is greater than the required tripping time. It is understandable that the tripping time required for the existing electric kettle is generally 15-25s. When dry-burning, the detected tripping time is mostly greater than 25s, which reduces the service life of the electric kettle. Therefore, it does not meet the requirements of this application.

[0048] 0 indicates that: when the electric kettle is dry-burned, the dry-burning tripping time of the temperature-sensitive metal sheet is less than the required tripping time. It is understandable that the tripping time required by the existing electric kettle is generally 15-25s. When the electric kettle is dry-burned, the detected tripping time is less than 15s, which does not meet the safety test standard; or, the temperature-sensitive metal sheet trips early when the electric kettle boils a small amount of water, which cannot meet the use needs of consumers. That is, when the electric kettle generally includes a first temperature-sensitive metal sheet for preventing dry-burning and a second temperature-sensitive metal sheet for boiling water and power off, when boiling a small amount of water, the first temperature-sensitive metal sheet does not trip earlier than the second temperature-sensitive metal sheet. Therefore, it does not meet the requirements of this application.

[0049] 1 represents: during dry boiling, the dry boiling tripping time of the temperature-sensitive metal sheet meets the required tripping time, and the temperature-sensitive metal sheet does not trip early under normal water boiling conditions (when the electric kettle generally includes a first temperature-sensitive metal sheet for preventing dry boiling and a second temperature-sensitive metal sheet for power off during water boiling, during normal water boiling, the first temperature-sensitive metal sheet does not trip earlier than the second temperature-sensitive metal sheet).

[0050] / characterized by: the heating element (such as the heating tube) in the electric kettle has a thickness, and there is a height difference between the upper and lower edges of the heating element on the second curved wall, which is generally 3-10mm, and may vary according to the curve of the second curved wall, specifically 5mm, 6mm, 7.5mm, 8mm. In addition, in order to ensure the conductivity of heat, the upper edge of the heating element cannot be higher than the upper edge of the second curved wall, so Figure 8-11 In the figure, the intersection of H1 / H and H2 / H is represented by / , which means that the intersection of / is not in line with the principle of the invention of this patent. Generally, it is impossible to make a product that conforms to the principle of the invention of this patent and it does not need to be considered in the embodiments.

[0051] Embodiment 1.

[0052] In this embodiment, the electric kettle comprises an outer shell 1 and an inner pot 2, wherein the inner pot 2 is completely arranged inside the outer shell 1, and the inner pot 2 comprises a stainless steel inner pot body 21 and an aluminum heat-conducting member 22 attached to the outer side of the bottom of the inner pot body 21, and the heating member 3 is a C-shaped heating tube, and the heating member 3 is arranged around the outer periphery of the aluminum heat-conducting member 22. The bottom of the inner pot body 21 has a first transverse wall 212 with a center and a first arc-shaped wall 211 extending upward and convexly around the first transverse wall 212, wherein the first transverse wall 212 is a circular smooth horizontal wall, and the first arc-shaped wall 211 is a first arc-shaped wall 211 formed by an arc line rotating around the edge of the first transverse wall 212. The height of the first arc-shaped wall 211 is generally 25-70 mm.

[0053] Specifically, the heating power of the electric kettle is 1800W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 128mm, the height of the first arc-shaped wall 211 is 60mm, the width of the first transverse wall 212 is 50mm, and the width of the second transverse wall 222 is 60mm. The positions of the heating element and the heat conducting plate are set on the above inner pot, and the test data are as follows Figure 8As shown, it can be seen that when the ratio of H1 / H is 0.04-0.2, and the ratio of H2 / H is 0.2-0.5, Characterization 1 is satisfied. Among them, when the ratio of H2 / H is 0.5-0.9, Characterization 1 is partially satisfied. The main reason is that the position of the heating element is relatively low. As the upper edge of the second curved wall extends upward, when the heat transferred upward by the second curved wall disperses the heat generated by the heating element sufficiently, the tripping time of the temperature-sensitive metal sheet can meet the required tripping time. However, since the position of the heat transfer plate is too high, it affects the installation of other components. At the same time, the heat transfer plate is larger in area and more expensive than the heat transfer plate at other heating element positions. Among them, when the ratio of H2 / H is 0.1-0.2, since the positions of the heating element and the heat transfer plate are too low, there is a small probability of early tripping events, which is not conducive to the consistent stability guarantee during mass production of products.

[0054] Embodiment 2.

[0055] Different from the first embodiment, in this embodiment, the inner tank body 202 of the electric kettle is made of glass, the inner tank bottom 201 of the electric kettle is formed by stretching a stainless steel plate, the heating power of the electric kettle is 1800W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 128mm, the height of the first arc-shaped wall 211 is 50mm, the width of the first transverse wall 212 is 30mm, and the width of the second transverse wall 222 is 40mm. Other features are the same as those of the first embodiment. Test data as shown in FIG. Fig. 9 As shown, it can be seen that when the ratio of H1 / H is between 0.05-0.25 and the ratio of H2 / H is between 0.15-0.5, Characterization 1 is satisfied. The selection principle is similar to that of the first embodiment.

[0056] Embodiment three.

[0057] Different from the first embodiment, in this embodiment, the inner tank body 202 of the electric kettle is made of glass, the inner tank bottom 201 of the electric kettle is formed by stretching a stainless steel plate, the heating power of the electric kettle is 1600W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 128mm, the height of the first arc-shaped wall 211 is 40mm, the width of the first transverse wall 212 is 0mm (that is, there is no first transverse wall 212, and the inner tank bottom is in a spherical shape), the width of the second transverse wall 222 is 20mm, and other features are the same as those of the first embodiment. Test data as shown in FIG. Fig.10 As shown, it can be seen that when the ratio of H1 / H is between 0.05-0.3 and the ratio of H2 / H is between 0.25-0.5, Characterization 1 is satisfied. The selection principle is similar to that of the first embodiment.

[0058] Embodiment 4.

[0059] Different from the first embodiment, in this embodiment, the heating power of the electric kettle is 1600W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 120mm, the height of the first arc-shaped wall 211 is 60mm, the width of the first transverse wall 212 is 20mm, the width of the second transverse wall 222 is 25mm, and other features are the same as those of the first embodiment. Test data are as follows Fig.11 As shown, it can be seen that when the ratio of H1 / H is between 0.05-0.4 and the ratio of H2 / H is between 0.25-1, Characterization 1 is satisfied. The selection principle is similar to that of Example 1.

[0060] It can be seen from the test data of Examples 1 to 4 that in order to ensure that in the case of different inner pots, the positions of the heating element 3 and the heat conducting plate 22 result in the electric kettle neither tripping too early nor tripping too late due to dry burning, reaching 100% or close to 100%, preferably, the height of the first arc-shaped wall 211 is H, the height of the lower edge of the heating element 3 is H1, 0.05H≤H1≤0.2H, and the height of the second arc-shaped wall 221 is H2, 0.25H≤H2≤0.5H.

[0061] It can be understood that the distance from the lower edge of the heating element 3 of the electric kettle of the present application to the first transverse wall 212 is 0.05-0.2 times the height of the first arc-shaped wall 211, specifically, it can be 0.05, 0.08, 0.1, 0.12, 0.13, 0.2.

[0062] It can be understood that the height of the lower edge of the heating element 3 refers to the distance between the lowest point where the heating element 3 contacts the inner pot 2 and the lowest point of the first transverse wall 212. When the setting height of the lower edge of the heating element 3 is too low, and the ratio of the distance from the lower edge of the heating element 3 to the first transverse wall 212 to the height of the first arc-shaped wall 211 is less than 0.05, the heat generated by the heating element 3 can be quickly transferred to the first transverse wall 212, and the speed of generating bubbles on the first transverse wall 212 increases, which easily leads to an increase in noise. As the setting height of the lower edge of the heating element 3 is increased, the lower edge of the heating element 3 is increased. When the ratio of the distance from the lower edge of the heating element 3 to the first transverse wall 212 to the height of the first curved wall 211 is greater than 0.2, the noise reduction when the electric kettle boils water is very limited, or even no longer reduced, because the lower edge of the heating element 3 is relatively far away from the first transverse wall 212, and there is no need to further increase the height of the heating element 3, especially when the outer shell 1 is provided outside the inner tank 2 of the electric kettle, the height of the heating tube is relatively large, and it is also easy to affect the installation of the outer shell 1. When the distance from the lower edge of the heating element 3 to the first transverse wall 212 is selected to be 0.05-0.2 times the height of the first curved wall 211, the noise when boiling water can be reduced to a certain extent.

[0063] Furthermore, the electric kettle in the prior art generally includes a kettle body and a base, a handle is provided on the kettle body, an upper coupler is provided at the bottom of the kettle body, and a lower coupler is provided on the base. When the kettle body is placed on the base, the kettle body can be powered on by coupling the upper coupler and the lower coupler. The kettle body generally includes an outer shell and an inner liner arranged in the outer shell, and a heating element 3 is provided on the outer wall of the inner liner. The heating element 3 heats the inner liner, and the inner liner contains a water source, thereby heating the water in the inner liner. Of course, there is also an electric kettle in the prior art in which the base and the kettle body are integrated. The power cord of this electric kettle is directly connected to the kettle body, and there is no need to set a base, which is low in cost.

[0064] At present, when boiling water in electric kettles on the market, a large number of bubbles will be generated on the inner surface of the inner pot, which is particularly obvious when the water boiling power is high. The noise generated by the bursting of bubbles is relatively high, up to 70 decibels, which greatly affects the user experience. Although the prior art discloses a method of setting a central plane and an arc surface surrounding the central plane on the inner surface of the inner pot to suppress noise, it only considers the effect of the size of the central plane on the noise, and does not realize the effect of the size of the central plane on the heating speed of the electric kettle when boiling water, resulting in the inability to take into account both the heating speed and the noise reduction.

[0065] In order to solve the problem that electric kettles in the prior art are not compatible with efficient heating and noise reduction, the present application provides an electric kettle, such as Figure 1-3 As shown, the electric kettle of the present application has an outer shell 1 and an inner liner 2 for holding liquid, the inner liner 2 includes an inner liner bottom 201 and an inner liner body 202 extending from the upper edge of the inner liner bottom 201 to the opening of the inner liner 2, the inner liner bottom 201 includes a first transverse wall 212 located in the center and a first curved wall 211 extending upward and convexly around the first transverse wall 212, the heating element 3 is arranged on the outer side of the inner liner 2 corresponding to the first curved wall 211, the heating element 3 is an annular heating tube, the heating tube surrounds the outer side of the first curved wall 211, the height of the first curved wall 211 is greater than the equivalent diameter of the first transverse wall 212, and the ratio of the equivalent diameter of the first transverse wall 212 to the equivalent diameter of the upper edge of the first curved wall 211 is 0.14-0.42. It can be understood that the equivalent diameter of the first transverse wall 212 is the diameter of a circle with the same area as the first transverse wall 212, and the equivalent diameter of the upper edge of the first arcuate wall 211 is the diameter of a circle with the same area as the area enclosed by the upper edge of the first arcuate wall 211 (specifically, the upper edge of the first arcuate wall 211 can be projected onto a horizontal plane and the area of ​​the projected area can be calculated).

[0066] In addition, preferably, the height of the inner tank body 202 is greater than the height of the first arc-shaped wall 211. When the volume of the inner tank is the same, the higher inner tank body can ensure that the electric kettle is slender and beautiful.

[0067] In the present application, the outer shell 1 includes a bottom shell covering the bottom of the inner pot 2 and a side shell surrounding the side of the inner pot 2. The bottom shell and the side shell can be integrally formed or separately arranged. Specifically, the periphery of the bottom shell can extend to the side of the inner pot 2 and be connected to the lower edge of the side shell, or the lower edge of the side shell can extend to the bottom of the inner pot 2 and be connected to the periphery of the bottom shell, or the lower edge of the side shell can be vertically connected to the periphery of the bottom shell.

[0068] The shell 1 of the present application is wrapped around the outside of the inner liner 2, and there are several specific schemes: Scheme 1: the upper edge of the shell 1 extends to the upper edge of the inner liner 2, and the inner liner 2 is completely placed in the space surrounded by the shell 1. The inner liner bottom 201 and the inner liner body 202 are completely wrapped by the shell. Such a setting of the electric kettle has a good heat preservation effect; Scheme 2: the upper edge of the shell 1 extends to between the upper edge of the inner liner bottom 201 and the upper edge of the inner liner body 202, that is, the shell 1 completely wraps the inner liner bottom 201 and partially wraps the inner liner body 202. With such a setting, the inner liner body 202 can be made of glass, and the user can see from the inner liner body 202 that is not covered by the shell. The wrapped part of the boiling water solution improves the user experience; Solution 3: The upper edge of the shell 1 extends to the upper edge of the inner liner bottom 201, that is, the shell 1 completely wraps the inner liner bottom 201, and the inner liner body 202 is exposed to the air, which has a better visual experience than the electric kettle of Solution 2; Solution 4: The upper edge of the shell 1 extends to the lower side of the upper edge of the inner liner bottom 201, that is, the inner liner bottom 201 is partially wrapped by the shell 1, and the inner liner bottom 201 is partially placed in the space formed by the shell 1, and the shell 1 wraps to the area above the heating element 3 of the inner liner bottom 201, and this solution also has a good visual experience. Among them, the shell 1 of Solution 1, Solution 2, and Solution 3 all completely wraps the inner liner bottom 201, and the shell 1 of Solution 4 partially wraps the inner liner bottom 201.

[0069] The present application can reduce noise while taking into account the heating speed by reasonably designing the size of the first transverse wall 212 of the center, so as to ensure that the electric kettle has low noise and fast water boiling speed, and meet the user's experience. The specific reason is that when the ratio of the first transverse wall 212 to the upper edge of the first curved wall 211 is large (greater than 0.42), the area of ​​the first curved wall 211 is relatively small, the area of ​​the first transverse wall 212 is relatively large, and the area of ​​the outer side of the bottom wall of the inner tank 2 for heat dissipation is relatively small. Although the electric kettle can obtain a faster heating speed, the heat conducted to the first curved wall 211 by the heating element 3 can be quickly transferred to the first transverse wall 212, and the probability of bubble generation on the first transverse wall 212 is increased at the same time. Moreover, since the area of ​​the first curved wall 211 is relatively small, it is not easy to form large bubbles, and the noise reduction effect is poor. Even if the heating speed is fast at this time, the user's experience is not good. When the ratio of the first transverse wall 212 to the upper edge of the first curved wall 211 is very small (<0.14), the area of ​​the first transverse wall 212 is small, the area of ​​the first curved wall 211 is large, and the area of ​​the heat dissipation outside the bottom wall of the inner pot 2 is relatively large, which will aggravate the heat dissipation of the heating element 3 during the heating process, resulting in a slower heating speed. Although the area of ​​the first curved wall 211 is relatively large at this time, it can obtain a better noise reduction effect, but the user experience is also not good. Therefore, only when the ratio of the first transverse wall 212 to the upper edge of the first curved wall 211 is moderate (0.14-0.42), it can not only meet the area of ​​the heat dissipation outside the bottom wall of the inner pot 2 without affecting the heating speed of the heating element 3, but also make the bubbles tend to form on the first curved wall 211 and easily gather into large bubbles, which can effectively reduce noise, and then take into account the heating noise and heating speed when the electric kettle is working. When the size and height of the upper edge of the first curved wall 211 of the inner pot 2 are constant, the above effect can be better verified. In particular, when the height of the first curved wall 211 is greater than the equivalent diameter of the first transverse wall 212, under the premise that the equivalent diameter of the first transverse wall 212 and the equivalent diameter of the upper edge of the first curved wall 211 remain unchanged: increasing the height of the first curved wall 211 can, on the one hand, make the first curved wall 211 steeper, and the bubbles generated on the first curved wall 211 can more easily slide along the first curved wall 211 and merge into large bubbles, thereby reducing the noise generated by bubble rupture; on the other hand, the height of the first curved wall 211 being greater than the equivalent diameter of the first transverse wall 212 can ensure that the area of ​​the first curved wall 211 is larger than the area of ​​the first transverse wall 212, thereby ensuring that the probability of bubbles being generated on the first curved wall 211 is higher, thereby further achieving the technical effect of reducing noise.

[0070] In the present application, the inner pot 2 of the electric kettle includes a stainless steel inner pot body 21 and an aluminum heat conductive member 22 attached to the outer side of the inner pot body 21, and a heating member 3 is arranged on the outer side of the aluminum heat conductive member 22. The inner pot body 21 can be formed by stretching or stamping a stainless steel plate, and the aluminum heat conductive member 22 is welded on the outer side of the inner pot body 21; the inner pot body 21 can also be formed by stretching or stamping a composite plate, and the composite plate includes a stainless steel layer and an aluminum layer, the stainless steel layer constitutes the inner pot body 21, and the aluminum layer constitutes the aluminum heat conductive member 22.

[0071] In a preferred embodiment of the present application, the inner liner 2 of the electric kettle may include a stainless steel inner liner body 21 and an aluminum heat conductor 22 welded to the outer side of the bottom of the inner liner body 21, a heating element 3 is welded to the periphery of the aluminum heat conductor 22, the inner liner body 21 is formed by stretching or stamping a stainless steel plate, the bottom of the inner liner body 21 and the aluminum heat conductor 22 together constitute the inner liner bottom 201, the first transverse wall 212 and the first arc-shaped wall 211 are arranged at the bottom of the inner liner body 21, and the portion of the inner liner body 21 located on the upper edge of the first arc-shaped wall 211 constitutes the inner liner body 202.

[0072] Specifically, the aluminum heat conductor 22 has a second transverse wall 222 and a second arc-shaped wall 221, the second transverse wall 222 is arranged below the first transverse wall 212, the second arc-shaped wall 221 surrounds the outside of the first arc-shaped wall 211, the heating element 3 heating element 3 is a C-shaped heating tube, the heating element 3 heating element 3 is arranged around the second arc-shaped wall 221, and a thermostat is arranged on the second transverse wall 222, and the temperature sensing element of the thermostat is offset relative to the center of the inner tank 2, that is, the center line of the inner tank 2 does not pass through the temperature sensing element of the thermostat. With such an arrangement, the temperature sensing element of the thermostat is offset relative to the center of the inner tank 2, and the temperature sensing element of the thermostat can be closer to the heating element 3 heating element 3. When the electric kettle is dry-burned, the thermostat can respond promptly and quickly, and promptly control the heating element 3 to cut off the power to the heating element 3, so as to avoid safety hazards.

[0073] In order to further reduce noise, preferably, the upper edge of the aluminum heat conductor 22 is lower than the upper edge of the first arc-shaped wall 211, and the heating element 3 is fixed around the outer wall of the aluminum heat conductor 22 opposite to the first arc-shaped wall 211. In this way, the heat generated by the heating element 3 is evenly transferred to the bottom of the inner pot 2 through the aluminum heat conductor 22, which can avoid the vibration of the inner pot 2 caused by the local over-temperature, and can slow down the speed of the bubble separation; in addition, the thermostat is generally installed on the aluminum heat conductor 22 corresponding to the first transverse wall 212. If the aluminum heat conductor 22 is set too high, the heat generated by the heating element 3 is easy to spread to the surroundings through the aluminum heat conductor 22, and the heat transferred to the thermostat is less, and the thermostat is not easy to trip, which can easily lead to the problem that the electric kettle cannot be tripped in time when it is dry-burned, affecting the safety performance of the product.

[0074] In addition, the liner body 202 is preferably cylindrical, and the upper edge of the first curved wall 211 is tangentially connected to the lower edge of the liner body 202. The liner body 202 preferably adopts a cylindrical structure, such as a straight cylinder, or a tapered cylinder (such as a tapered cylinder with a larger bottom and a smaller top), which is conducive to the production of the liner body 202 and the connection between the liner body 202 and the first curved wall 211; especially when the upper edge of the first curved wall 211 is tangentially connected to the lower edge of the liner body 202, a continuous shape will be formed between the liner body 202 and the first curved wall 211, and the convenience of cleaning after use by consumers will become very easy, thereby improving the user experience. The liner body 202 includes a second liner body 2021 and a first liner body 2022 integrally formed with the upper edge of the first curved wall 211, and the first liner body 2022 and the second liner body 2021 are welded and connected. In this way, a part of the inner liner body 202 and the first curved wall 211 are set as an integrally formed structure. On the one hand, it is convenient for the first curved wall 211 and the first transverse wall 212 to be connected to the inner liner body 202 at the same time as they are formed. On the other hand, the connection method of the inner liner body 202 will be simpler, the process difficulty will be reduced, and it will be conducive to industrial manufacturing.

[0075] In another preferred embodiment of the present application, the inner pot 2 is made of a composite plate, the composite plate includes a stainless steel layer and an aluminum layer, the stainless steel layer constitutes the inner pot body 21, and the aluminum layer constitutes the aluminum heat conductor 22. In this way, the aluminum heat conductor 22 is constituted by the aluminum layer, which can effectively avoid the problem of too low heating speed caused by the loose welding between the aluminum heat conductor 22 and the inner pot body 21, and greatly improve the water boiling speed of the electric kettle.

[0076] In the present application, the heating element 3 is preferably a C-shaped heating tube, and the heating element 3 has a notch, and the projection of the temperature sensing element of the thermostat on the horizontal plane is located outside the projection of the horizontal plane formed by the center of the inner pot bottom 201 and the area formed by the line connecting the two ends of the notch. By adopting the above scheme, the temperature sensing element of the thermostat is set at a position corresponding to the cold zone of the heating element 3, which can ensure that the thermostat can sense the temperature in time and avoid the safety hazards caused by not tripping in time. It can be understood that the heating element 3 can also be a multi-layer spiral heating tube arranged around the outside of the first arc-shaped wall 211, and the heating element 3 can also be a plurality of split heating tubes uniformly distributed around the outer periphery of the first arc-shaped wall 211. In addition, the present application is particularly intended to solve the problem that when the power of the heating element 3 is not less than 1500W or the ratio of the power of the heating element 3 to the maximum water boiling capacity of the electric kettle is not less than 1000W / L, the high-power electric kettle can achieve a good balance between high-speed heating and noise reduction. Of course, the technical solution of the present application is also applicable to electric kettles whose power of the heating element 3 is less than 1500W or whose ratio of the power of the heating element 3 to the maximum water boiling capacity is less than 1000W / L. It can be understood that for an electric kettle with a maximum water level, the maximum water boiling capacity of the electric kettle is the capacity marked by the maximum water level of the electric kettle, and for an electric kettle that can automatically fill water, the maximum water boiling capacity can be the maximum water boiling capacity preset by the machine or the selectable maximum water boiling capacity.

[0077] In addition, in the present application, the inner surface of the inner pot 2 is provided with a minimum water level mark, and the minimum water level mark is higher than the upper edge of the first curved wall 211. The minimum water level mark is also the minimum water capacity allowed when the electric kettle is boiling water. The volume of the area enclosed by the first transverse wall 212 and the curved surface is also the volume of the inner pot bottom 201 of the electric kettle. Designing the upper edge of the first curved wall 211 to be lower than the minimum water level mark can ensure that the first curved wall 211 is always in contact with water when the user boils water, and avoids the water level being too low, resulting in the upper end of the first curved wall 211 being exposed to the air while the lower end is immersed in water, resulting in a large temperature difference between the upper and lower ends of the first curved wall 211, causing the first curved wall 211 to vibrate and cause the bubbles to escape.

[0078] In the present application, the first transverse wall 212 is preferably a circular plane extending horizontally. The circular first transverse wall 212 can ensure that the distance between the heating element 3 and the edge of the first transverse wall 212 is equal, the temperature on the first transverse wall 212 is relatively balanced, and the convection of the water flow on the first transverse wall 212 can be reduced, and the speed of the bubbles on the first transverse wall 212 can be reduced, so as to achieve the purpose of reducing noise. It can be understood that the first transverse wall 212 is a plane extending laterally, and the plane can be a smooth plane, and the plane can also be provided with protrusions or patterns. The first transverse wall 212 can also be a plane with a small inclination angle with the horizontal plane, such as a plane inclined at 5° with the horizontal plane. Of course, the first transverse wall 212 can also be a surface with a certain height fluctuation as a whole, such as a fluctuating surface with a height difference of 2 or 3 mm between the highest point and the lowest point, etc. In the case of meeting the spirit of the present application, other embodiments of the first transverse wall 212 should also be within the scope of protection of the present application. In addition, the shape of the first transverse wall 212 can be circular, elliptical, rounded rectangle, etc., which will not be repeated here.

[0079] In the present application, the first curved wall 211 is preferably a curved surface formed by an arc line rotating around the edge of the first transverse wall 212, and the equivalent diameter of the first curved wall 211 is preferably gradually increased from bottom to top, that is, the width of the first curved wall 211 is gradually increased. In this way, bubbles generated at any position of the first curved wall 211 during the water boiling process can slide along the first curved wall 211, so that small bubbles converge into large bubbles, reducing the noise generated when the bubbles burst. It can be understood that the first curved wall 211 can be a spherical surface, an ellipsoidal surface, or a curved surface of other shapes.

[0080] It can be understood that the equivalent diameter ratio of the first transverse wall 212 of the inner pot 2 of the electric kettle of the present application to the upper edge of the first arcuate wall 211 is between 0.14-0.42, specifically, it can be 0.14, 0.20, 0.25, 0.3, 0.35, 0.4, 0.42, etc.

[0081] Embodiment five.

[0082] Different from the fifth embodiment, in this embodiment, the inner tank body 202 of the electric kettle is made of glass, the inner tank bottom 201 of the electric kettle is formed by stretching a stainless steel plate, the heating power of the electric kettle is 1800W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 128mm, the height of the first arc-shaped wall 211 is 60mm, the distance between the heating element 3 and the first transverse wall 212 is 6mm, and the other features are the same as those of the first embodiment. The heating speed and noise data of the electric kettle corresponding to the equivalent diameter of the first transverse wall 212 are shown in Tables 2 and 3. Figure 5 , where the heating speed of the electric kettle is characterized by the time required to heat 1.7L of water from 40℃ to 90℃.

[0083] from Figure 5 It can be seen that as the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 increases, the heating speed of the electric kettle gradually increases, and the noise generated when the electric kettle boils water continues to decrease. When the equivalent diameter ratio increases to 0.42, continuing to increase the equivalent diameter ratio does not significantly increase the heating speed, but continuing to increase the equivalent diameter ratio will cause the noise when boiling water to increase significantly. As the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 decreases, the heating speed of the electric kettle gradually decreases, and the noise when the electric kettle boils water continues to decrease. When the equivalent diameter ratio decreases to 0.12, continuing to reduce the equivalent diameter ratio has little effect on reducing the noise, but the heating speed will be significantly reduced. Therefore, when the equivalent diameter ratio of the electric kettle of this embodiment is between 0.12-0.42, it can take into account both faster heating speed and noise reduction, so that the noise when boiling water is even lower than 60 decibels.

[0084] Table 1: Noise and heating rate data corresponding to different equivalent diameter ratios in Example 5.

[0085] Equivalent diameter ratio 0.05 0.08 0.1 0.12 0.19 0.25 0.31 0.39 0.42 0.47 0.51 0.58 0.7 0.9 Noise(db) 58.1 58.2 58.4 58.6 58.7 58.9 59.2 59.5 59.8 60.8 61.9 63 64.4 65.1 Heating speed(s) 236.2 233.1 230 226.8 226.1 225.8 225.1 224.6 223 222.2 222.1 222 221 221.2

[0086] Embodiment six.

[0087] Different from the fifth embodiment, in this embodiment, the inner tank body 202 of the electric kettle is made of glass, the inner tank bottom 201 of the electric kettle is formed by stretching a stainless steel plate, the heating power of the electric kettle is 1800W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 128mm, the height of the first arc-shaped wall 211 is 60mm, the distance between the heating element 3 and the first transverse wall 212 is 6mm, and the other features are the same as those of the first embodiment. The heating speed and noise data of the electric kettle corresponding to the equivalent diameter of the first transverse wall 212 are shown in Tables 2 and 3. Figure 5 , where the heating speed of the electric kettle is characterized by the time required to heat 1.7L of water from 40℃ to 90℃.

[0088] from Figure 5It can be seen that as the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 increases, the heating speed of the electric kettle gradually increases, and the noise generated when the electric kettle boils water continues to decrease. When the equivalent diameter ratio increases to 0.42, continuing to increase the equivalent diameter ratio does not significantly increase the heating speed, but continuing to increase the equivalent diameter ratio will cause the noise when boiling water to increase significantly. As the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 decreases, the heating speed of the electric kettle gradually decreases, and the noise when the electric kettle boils water continues to decrease. When the equivalent diameter ratio decreases to 0.12, continuing to reduce the equivalent diameter ratio has little effect on reducing the noise, but the heating speed will be significantly reduced. Therefore, when the equivalent diameter ratio of the electric kettle of this embodiment is between 0.12-0.42, it can take into account both faster heating speed and noise reduction, so that the noise when boiling water is even lower than 60 decibels.

[0089] Table 2: Noise and heating rate data corresponding to different equivalent diameter ratios of Example 6.

[0090] Equivalent diameter ratio 0.05 0.08 0.1 0.12 0.19 0.25 0.31 0.39 0.42 0.47 0.51 0.58 0.7 0.9 Noise(db) 58.2 58.3 58.5 58.5 58.9 58.9 59.1 59.5 59.8 60.7 61.8 92.8 64.5 65.2 Heating speed(s) 241.8 238.7 235.5 231.5 230.9 230.2 229.6 229.6 228.2 227 226.9 226.5 225.8 226.1

[0091] Embodiment seven.

[0092] Different from the fifth embodiment, in this embodiment, the heating power of the electric kettle is 1600W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 120mm, the height of the first arc-shaped wall 211 is 40mm, the distance between the heating element 3 and the first transverse wall 212 is 10mm, and the other features are the same as those of the first embodiment. The heating speed and noise data of the electric kettle corresponding to the equivalent diameter of the first transverse wall 212 are shown in Tables 3 and Figure 6 , where the heating speed of the electric kettle is characterized by the time required to heat 1.5L of water from 40℃ to 90℃.

[0093] from Figure 6 It can be seen that as the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 increases, the heating speed of the electric kettle gradually increases, and the noise generated when the electric kettle boils water continues to decrease. When the equivalent diameter ratio increases to 0.44, continuing to increase the equivalent diameter ratio does not significantly increase the heating speed, but continuing to increase the equivalent diameter ratio will cause the noise when boiling water to increase significantly. As the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 decreases, the heating speed of the electric kettle gradually decreases, and the noise when the electric kettle boils water continues to decrease. When the equivalent diameter ratio decreases to 0.10, continuing to reduce the equivalent diameter ratio has little effect on reducing the noise, but the heating speed will be significantly reduced. Therefore, when the equivalent diameter ratio of the electric kettle of this embodiment is between 0.10-0.44, it can take into account both faster heating speed and noise reduction, so that the noise when boiling water is even lower than 60 decibels.

[0094] Table 3: Noise and heating rate data corresponding to different equivalent diameter ratios of Example 7.

[0095] Equivalent diameter ratio 0.05 0.08 0.1 0.14 0.19 0.25 0.31 0.39 0.44 0.47 0.51 0.58 0.7 0.9 Noise(db) 57.5 57.7 57.8 58.1 58.5 58.8 58.9 59.2 59.5 60.8 61.5 62.2 62.8 63.2 Heating speed(s) 229.1 225.9 220.8 219.8 219 219.1 218.8 217.8 216.7 215.3 215.9 215.2 214.5 214.6

[0096] Embodiment eight.

[0097] Different from the fifth embodiment, in this embodiment, the heating power of the electric kettle is 1200W, the equivalent diameter of the upper edge of the first arc-shaped wall 211 is 120mm, the height of the first arc-shaped wall 211 is 15mm, the distance between the heating element 3 and the first transverse wall 212 is 6mm, and the other features are the same as those of the first embodiment. The heating speed and noise data of the electric kettle corresponding to the equivalent diameter of the first transverse wall 212 are shown in Tables 4 and Figure 7 , where the heating speed of the electric kettle is characterized by the time required to heat 1.2L of water from 40℃ to 90℃.

[0098] from Figure 7 It can be seen that as the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 continues to increase, the heating speed of the electric kettle gradually increases, and the noise generated when the electric kettle boils water continues to decrease. When the equivalent diameter ratio increases to 0.42, continuing to increase the equivalent diameter ratio does not significantly increase the heating speed, but continuing to increase the equivalent diameter ratio will cause the noise when boiling water to increase significantly. As the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first arc-shaped wall 211 continues to decrease, the heating speed of the electric kettle gradually decreases, and the noise when the electric kettle boils water continues to decrease. When the equivalent diameter ratio decreases to 0.14, continuing to reduce the equivalent diameter ratio has little effect on reducing the noise, but the heating speed will be significantly reduced. Therefore, when the equivalent diameter ratio of the electric kettle of this embodiment is between 0.14-0.42, it can take into account both faster heating speed and noise reduction, so that the noise when boiling water is even lower than 60 decibels.

[0099] Table 4: Noise and heating rate data corresponding to different equivalent diameter ratios in Example 8.

[0100] Equivalent diameter ratio 0.05 0.08 0.1 0.14 0.17 0.25 0.31 0.39 0.42 0.47 0.51 0.58 0.7 0.9 Noise(db) 56.3 56.3 56.5 56.8 57.2 57.6 58 58.6 59.2 60.4 61.2 62 62.4 62.5 Heating speed(s) 244.8 241 237.5 234.8 234.1 233.4 233 232.7 230.8 230.4 229.7 230.1 228.7 229.5

[0101] It can be seen from the test data of the fifth to eighth embodiments that, as the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first curved wall 211 increases, the heating speed of the electric kettle gradually increases and then remains relatively unchanged. On the contrary, as the equivalent diameter ratio of the first transverse wall 212 to the upper edge of the first curved wall 211 decreases, the noise of the electric kettle when boiling water gradually decreases and then remains relatively unchanged. When the equivalent diameter ratio is between 0.14 and 0.42, the electric kettle has a smaller noise (less than 60 decibels) and a faster heating speed when boiling water. In addition, it can be seen from the comparison of the test data of the fourth embodiment and the third embodiment that when the height of the first curved wall 211 is different, the change trend of the noise and heating speed of the electric kettle when boiling water is basically unchanged, but when the height of the first curved wall 211 is larger (greater than the equivalent diameter of the first transverse wall 212), the noise reduction effect and heating speed are better than the noise reduction effect and heating speed when the height of the first curved wall 211 is smaller (less than the equivalent diameter of the first transverse wall 212). It can be understood that if the power of the heating element 3 of Example 1, Example 2 and Example 3 is slightly smaller than 1400W, and the power of the heating element 3 of Example 4 is slightly smaller than 1000W, the noise reduction effect and the changing trend of the heating speed are also the same, which will not be elaborated here due to space limitations.

[0102] In addition, although the electric kettle of the present application can only reduce the noise by a few decibels, since decibel is a unit used to measure sound intensity and is usually used to characterize the gain of sound, a noise reduction of 3 decibels is equivalent to a sound intensity reduction to 50% of the original sound intensity. Therefore, the present application can effectively improve the problem of loud noise when the electric kettle boils water and improve the heating speed by reasonably setting the equivalent diameter ratio of the first transverse wall 212 and the upper edge of the first arc-shaped wall 211.

[0103] It can be understood that the electric kettle of the present application can be an electric kettle with an integrated kettle body and a base, or an electric kettle with a separate kettle body and a base. For the separate electric kettle, the inner tank 2, the outer shell 1, the heating element 3, the heating element 3 and other components are arranged on the kettle body, and the kettle body and the power base are connected through upper and lower connectors. The temperature-sensitive metal sheet is arranged on the upper connector, and the upper connector is installed on the second horizontal wall 222.

[0104] It can be understood that the inner bottom 201 and the inner body 202 of the electric kettle of the present application can be formed by integrally stretching or stamping a metal plate, or can be formed by welding different metal plates after stretching or stamping, or can be formed by connecting the inner bottom 201 formed by stretching or stamping a metal plate and the inner body 202 formed by glass.

[0105] Furthermore, without affecting the silencing effect and facilitating the installation of the temperature-sensitive metal sheet, the second transverse wall 222 is not smaller than the first transverse wall 212 .

[0106] Furthermore, in order to achieve dry-burning tripping of the temperature-sensitive metal sheet more stably, the temperature-sensitive element forms a temperature-sensitive zone, and the outer wall distance between the outer edge of the temperature-sensitive zone and the lower edge of the heating tube is less than 19 mm and greater than 14 mm.

[0107] Furthermore, in order to further reduce noise, the equivalent diameter of the first transverse wall is d, the equivalent diameter of the inner liner body at the top of the first arc-shaped wall is D, and H is greater than d and less than 0.5D.

[0108] The technical features in this embodiment can be arbitrarily combined to form different technical solutions.

[0109] The above-described embodiments only express several embodiments of the present invention, and the description is relatively specific and detailed, but the contents described are only embodiments adopted to facilitate understanding of the present invention, and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed by the present invention, but the scope of patent protection of the present invention shall still be defined by the attached claims.

Claims

1. An electric kettle, comprising an inner liner body for containing liquid and a heat conducting plate arranged outside the inner liner body, characterized in that: The inner pot body includes a first curved wall extending upward and outward from the bottom, the heat conducting plate includes a second curved wall extending along the first curved wall, and a second transverse wall extending from the lower edge of the second curved wall toward the bottom center of the inner pot body, the second transverse wall is provided with a temperature sensing element for preventing dry burning, the equivalent diameter of the second transverse wall is not greater than 50% of the equivalent diameter of the top end of the first curved wall, the heating element is arranged on the second curved wall, the height of the first curved wall is H, the height of the lower edge of the heating element is H1, 0.05H≤H1≤0.2H, the height of the second curved wall is H2, 0.25H≤H2≤0.5H.

2. An electric kettle according to claim 1, characterized in that: The height of the upper edge of the heating element is lower than the height of the second arc-shaped wall.

3. The electric kettle according to claim 1, characterized in that: The inner container body comprises a first transverse wall extending from the lower edge of the first arc-shaped wall toward the center of the bottom, and a second transverse wall extending along the first transverse wall.

4. The electric kettle according to claim 1, characterized in that: The inner liner body includes a first inner liner body integrally formed with the upper edge of the first arc-shaped wall, and a second inner liner body connected to the first inner liner body by welding.

5. The electric kettle according to claim 3, characterized in that: The ratio of the equivalent diameter of the first transverse wall to the equivalent diameter of the upper edge of the first arc-shaped wall is 0.14-0.

42.

6. The electric kettle according to claim 3, characterized in that: The second transverse wall is not smaller than the first transverse wall.

7. The electric kettle according to claim 3, characterized in that: The equivalent diameter of the first transverse wall is d, the equivalent diameter of the inner container body at the top end of the first arc-shaped wall is D, and H is greater than d and less than 0.5D.

8. The electric kettle according to claim 1, characterized in that: The temperature sensing element forms a temperature sensing area, and the outer wall distance between the outer edge of the temperature sensing area and the lower edge of the heating tube is less than 19 mm and greater than 14 mm.

9. The electric kettle according to claim 1, characterized in that: It comprises a kettle body and a separately arranged power base, the kettle body and the power base are connected through an upper connector and a lower connector, the temperature-sensitive metal sheet is arranged on the upper connector, and the upper connector is installed on the second transverse wall.

10. The electric kettle according to claim 1, characterized in that: The heating element is a non-enclosed heating tube with an opening, and the heating tube is wound around the second arc-shaped wall.

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