Heating diaphragm and its manufacturing method, heating tube and heating electrical equipment

Abstract

The present invention provides a heating diaphragm, a method for manufacturing the same, a heating tube, and a heating electrical device. The raw materials for the heating diaphragm include natural graphite and / or graphene, and the weight of a heating diaphragm with a length of 1 decimeter is 0.02 to 2 g.

Description

[Technical Field]

[0001] This disclosure claims priority to the Chinese patent application filed on 26 January 2024 with application number 2024101198333, all of which are incorporated herein by reference.

[0002] This disclosure relates to the technical field of electrical equipment, and more specifically to heating diaphragms and methods for manufacturing the same, heating tubes, and heating electrical equipment. [Background technology]

[0003] Conventional electric ovens primarily heat the air inside the chamber using heating tubes, further heating the food, and also directly heating the food's surface through thermal radiation. Currently, electric ovens, microwave ovens, and steam ovens on the market utilize heating elements such as metal heating tubes (maximum heating temperature range of 550-750°C), quartz heating tubes (heating wire temperature range of 660-800°C), halogen heating tubes (maximum heating temperature less than 1000°C), and carbon fiber heating tubes (maximum heating temperature less than 1000°C). However, these heating tubes have problems such as insufficient heating speed within the heating temperature range, insufficient temperature, and heavy mass. This results in longer cooking times, making it difficult to achieve a crispy exterior and fluffy interior during the heating process, leading to a reduced user experience. Furthermore, the heavy total weight of current heating tubes is detrimental to the design requirements for weight reduction. [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] This disclosure aims to solve at least one of the technical problems in the related technology to a certain extent. To that end, one object of this disclosure is to provide a heating diaphragm that is lightweight, has a high heating temperature, or has a fast heating rate.

[0005] In one aspect of this disclosure, the disclosure provides a heating diaphragm. According to an embodiment of the disclosure, the raw materials of the heating diaphragm include natural graphite and / or graphene, and the weight of the heating diaphragm with a length of 1 decimeter is 0.02 to 2 g. Thus, a graphite material heating diaphragm manufactured using natural graphite or graphene increases the heating temperature of the heating diaphragm and speeds up the heating rate, thus helping to achieve higher heating temperatures and higher heating efficiency. Furthermore, the heating diaphragm of the disclosure uses natural graphite, and natural graphite deposits are abundant among the Earth's mineral resources. At the same time, the carbon-based diaphragm material does not require high-temperature graphitization in the manufacturing process and does not need to be manufactured through other processes, enabling continuous production and cost reduction. Overall, the heating diaphragm of the disclosure has advantages such as a wide range of raw material sources, a simple manufacturing process, excellent product stability, and easily adjustable performance parameters according to needs, and has significant advantages in terms of reducing product costs, improving product reliability, and expanding the range of product types. If artificial graphite is used, an additional process is required to manufacture the artificial graphite, which significantly increases the cost and time of manufacturing the heating diaphragm and reduces production efficiency. When graphene is used as a raw material, it is advantageous not only to obtain heating diaphragms with a high carbon content, but the processing process is simple and mature, and the manufacturing cost is not high. Furthermore, since the mass of the heating diaphragm of this disclosure is light, and significantly less than the weight of heating tubes such as metal heating tubes or quartz tubes, it is further useful in designing a lighter heating diaphragm of this disclosure, and consequently in obtaining a lighter heating tube. If the weight of a heating diaphragm per unit length is less than 0.02 g, the manufacturability of the heating diaphragm is relatively reduced, and consequently affects the overall performance of the heating diaphragm, and if the weight of a heating diaphragm per unit length exceeds 2 g, the manufacturability of the heating diaphragm is relatively reduced.

[0006] According to embodiments of this disclosure, the heating diaphragm has a sheet-like structure, the graphite and graphene have a sheet-like structure, and the sheet-like stretched plane of the heating diaphragm and the sheet-like stretched plane of the graphite and / or graphene basically coincide.

[0007] According to the embodiments of this disclosure, the time it takes for the heating diaphragm to reach its maximum heating temperature is 0.1 s to 2 s.

[0008] According to the embodiments of this disclosure, the heat resistance temperature of the heating diaphragm is 2500°C or higher.

[0009] According to the embodiments of this disclosure, the maximum heating temperature of the heating diaphragm is 500°C to 1700°C.

[0010] According to the embodiments of this disclosure, the material of the heating diaphragm is graphite.

[0011] According to the embodiments of this disclosure, the power of the heating diaphragm is 15W to 10000W.

[0012] According to embodiments of the present disclosure, the heating diaphragm includes a plurality of heating units arranged sequentially along its length, wherein adjacent heating units are spaced apart and connected by connecting segments.

[0013] According to the embodiments of this disclosure, each heating unit is provided with a perforated hole.

[0014] In other embodiments of the present disclosure, the present disclosure provides a method for manufacturing the aforementioned exothermic diaphragm. According to embodiments of the present disclosure, the method for manufacturing the exothermic diaphragm includes the steps of: providing natural graphite and intercalating it to obtain graphite oxide; subjecting the graphite oxide to an expansion treatment to obtain expanded graphite; rolling and cutting the expanded graphite to obtain the exothermic diaphragm; or including the steps of: mixing graphene and an additive and dispersing them uniformly to obtain a dispersion; applying the dispersion to obtain a dispersion film; subjecting the dispersion film to a second heat treatment to obtain a carbon matrix film; and rolling and cutting the carbon matrix film to obtain the exothermic diaphragm. As a result, a graphite-based heating diaphragm manufactured using natural graphite or graphene can increase the heating temperature and speed of the heating diaphragm, thus contributing to higher temperature heating and more efficient heating. Furthermore, the heating diaphragm of this disclosure uses natural graphite, which is abundant in the Earth's mineral resources. At the same time, the carbon-based diaphragm material does not require high-temperature graphitization during the manufacturing process and does not require production through other processes, enabling continuous production and cost reduction. Overall, carbon-based diaphragm material has advantages such as a wide range of raw material sources, a simple manufacturing process, excellent product stability, and easily adjustable performance parameters according to needs, offering significant advantages in terms of reducing product costs, improving product reliability, and expanding product variety. If artificial graphite is used, an additional process is required to manufacture it, which significantly increases the cost and time of manufacturing the exothermic diaphragm and reduces production efficiency. Using graphene as a raw material is advantageous not only for obtaining exothermic diaphragms with a high carbon content, but also because the processing process is simple and mature, and the manufacturing cost is not high.

[0015] According to an embodiment of the present disclosure, the method for manufacturing the aforementioned heating diaphragm includes the steps of mixing the graphene micropieces and an additive and uniformly dispersing them to obtain a dispersion liquid; applying the dispersion liquid to obtain a dispersion liquid film; performing a second heat treatment on the dispersion liquid film to obtain a carbon-based primary film; and performing rolling and cutting on the carbon-based primary film to obtain the heating diaphragm.

[0016] In another aspect of the present disclosure, the present disclosure provides a heating tube. According to an embodiment of the present disclosure, the heating tube includes the aforementioned heating diaphragm. Thereby, the heating tube has a light mass, a high heating temperature, and a high heating rate. As can be understood by those skilled in the art, the heating tube has all the features and advantages of the aforementioned heating diaphragm, and detailed descriptions are omitted herein.

[0017] In another aspect of the present disclosure, the present disclosure provides a heating electric appliance. According to an embodiment of the present disclosure, the heating electric appliance includes the aforementioned heating tube. Thereby, the heating electric appliance has a high heating rate and a high heating temperature. As can be understood by those skilled in the art, the heating electric appliance has all the features and advantages of the aforementioned heating diaphragm, and detailed descriptions are omitted herein.

[0018] According to an embodiment of the present disclosure, the heating electric appliance is an electric oven, a microwave oven, a steam oven, an electric pot, an electric blanket, an electric hot air blower, an electric heater, a bathroom heater dryer, a radiant heater, or a disinfection cabinet.

Brief Description of the Drawings

[0019] The above and / or additional aspects and advantages of the present disclosure will become apparent and be readily understood from the description of the embodiments in combination with the following drawings. [Figure 1] It is a schematic diagram of the thermal radiation of the heating diaphragm of the present disclosure. [Figure 2] It is a schematic diagram of the thermal radiation of a heating tube in the prior art. [Figure 3] It is a schematic diagram of the structure of the heating diaphragm in an embodiment of the present disclosure. [Figure 4] This disclosure provides schematic diagrams of the structure of a heating diaphragm in several other embodiments. [Figure 5] This disclosure provides schematic diagrams of the structure of a heating diaphragm in several other embodiments. [Figure 6] This disclosure provides schematic diagrams of the structure of a heating diaphragm in several other embodiments. [Figure 7] This is a schematic diagram of the structure of a heating tube in the present disclosure or some embodiments. [Figure 8] This is a schematic diagram of the structure of a heating tube in the present disclosure or some embodiments. [Figure 9] This is a schematic diagram of the structure of a heating tube in the present disclosure or some embodiments. [Figure 10] This disclosure shows a temperature-resistance curve diagram of a heating diaphragm in one embodiment. [Modes for carrying out the invention]

[0020] The methods of the present disclosure will be illustrated below by combining examples. As those skilled in the art will understand, the following examples are merely illustrative of the present disclosure and should not be construed as limiting the scope of the present disclosure. Where specific techniques or conditions are not specified in the examples, the techniques or conditions described in the literature in the art or the product instructions will be followed. Where the manufacturers of the reagents or equipment used are not specified, they are all commercially available, general-purpose products.

[0021] The present disclosure will be described below with reference to specific examples, which are for descriptive purposes only and do not limit the present disclosure in any way.

[0022] In one aspect of this disclosure, the disclosure provides a heating diaphragm. According to some embodiments of the disclosure, the raw material of the heating diaphragm comprises natural graphite and / or graphene, and the weight of the heating diaphragm with a length of 1 decimeter is 0.02 to 2 g, for example, 0.02 g, 0.04 g, 0.05 g, 0.1 g, 0.2 g, 0.5 g, 1 g, 1.5 g, 2 g, etc. Thus, a graphite material heating diaphragm manufactured using natural graphite or graphene increases the heating temperature of the heating diaphragm and speeds up the heating rate, thus helping to achieve higher heating temperatures and higher heating efficiency. Furthermore, the heating diaphragm of the disclosure uses natural graphite, and natural graphite deposits are abundant in the Earth's mineral resources. At the same time, the carbon-based diaphragm material does not require high-temperature graphitization in the manufacturing process and does not need to be manufactured through other processes, enabling continuous production and cost reduction. Overall, the heat-generating diaphragm of this disclosure has advantages such as a wide range of raw material sources, a simple manufacturing process, excellent product stability, and easily adjustable performance parameters according to needs, offering significant advantages in terms of reducing product costs, improving product reliability, and expanding product variety. If artificial graphite is used, an additional process for manufacturing artificial graphite is required, which significantly increases the manufacturing cost and time of the heat-generating diaphragm and reduces production efficiency. When graphene is used as a raw material, it is not only advantageous to obtain a heat-generating diaphragm with a high carbon content, but the processing process is simple and mature, and the manufacturing cost is not high. Furthermore, the mass of the heat-generating diaphragm of this disclosure is light, significantly less than the weight of metal heating tubes or heating tubes such as quartz tubes, which further contributes to the lightweight design of the heat-generating diaphragm of this disclosure, and consequently contributes to obtaining lighter heating tubes. If the weight of a unit length of the heating diaphragm is less than 0.02 g, the manufacturability of the heating diaphragm is relatively reduced, which in turn affects the overall performance of the heating diaphragm. If the weight of a unit length of the heating diaphragm is greater than 2 g, the manufacturability of the heating diaphragm is also relatively reduced.Furthermore, as the weight of the heating diaphragm per unit length increases, the heating power of the heating diaphragm gradually increases. In other words, there is a positive correlation between the weight of the heating diaphragm per unit length and the heating power of the heating diaphragm, and by adjusting the weight of the heating diaphragm per unit length, the required heating power of the heating diaphragm can be adjusted.

[0023] According to the heat calculation formula Q = m * Cp * ΔT (where Q - heat quantity, m - mass, Cp - specific heat, ΔT - temperature rise), under the same heat quantity, the smaller the mass * specific heat, the greater the temperature rise. Since the heat-generating diaphragm of this disclosure has a light mass and a low specific heat, the product of its mass and specific heat is small. Therefore, under the same heat quantity conditions, the carbon-based diaphragm has a faster temperature rise rate and a higher heat-generating temperature. In one specific embodiment of this disclosure, the specific heat of the carbon-based heat-generating diaphragm is 0.71 kJ / (kg * K) and its mass is 0.216 g. The specific heat of the metal heating wire of a heating tube such as a metal tube or quartz tube is 0.49 kJ / (kg * K) and its mass is 5 g. As is clear from this, the carbon-based diaphragm of this disclosure can reach a faster temperature rise rate and a higher heat-generating temperature compared to the metal heating wire.

[0024] Furthermore, the formula for radiative heat transfer is Q = ε * σ * A * (T1 4 -T2 4 (where Q - heat quantity, ε - emissivity, σ - Boltzmann constant, T - surface temperature of the object). As is clear from this, the difference between radiative heat transfer and the fourth power of the surface temperatures of the two objects is directly proportional, and because the surface temperature of the carbon-based diaphragm is higher, the radiative heat transfer Q becomes higher, and consequently, the carbon-based diaphragm heating tube has a faster heat generation rate than metal tubes and quartz tubes.

[0025] In some embodiments of this disclosure, the raw material graphene may be graphene nanoplatelets, which refer to ultrathin graphene layered deposits having more than 10 carbon layers and a thickness in the range of 5 to 100 nanometers. Graphene nanoplatelets have excellent thermal conductivity and tensile strength, which in turn contributes to improving the heat generation temperature and mechanical strength of the manufactured heat-generating diaphragm.

[0026] According to some embodiments of this disclosure, the heating diaphragm exhibits a sheet-like structure, the graphite and / or graphene used as raw materials in the manufacture of the heating diaphragm also exhibit a sheet-like structure, and the sheet-like stretched plane of the heating diaphragm and the sheet-like stretched plane of natural graphite and / or graphene basically coincide. As a result, as shown in Figure 1, when a sheet-like heating diaphragm generates heat, the heat is mainly radiated along the direction perpendicular to the heating surface (i.e., the plane of the diaphragm), and because it is highly directional and the radiated heat is more concentrated, the heating efficiency can be effectively improved and heat loss can be reduced. In the current prior art, referring to Figure 2, the heat radiation from the heating tube core 1 (e.g., a metal heating tube core or a quartz tube core) is emitted uniformly on all sides, and the heat cannot be emitted in a concentrated manner, which usually leads to the waste of heat and a decrease in heating efficiency. As is clear from this comparison, the direction of heat radiation of the heating diaphragm of this disclosure is more concentrated, allowing for more effective directional heating of objects awaiting heating and improving heating efficiency. In this context, "basically coincide" means that the sheet-like stretched plane of the heat-generating diaphragm and the sheet-like stretched plane of the natural graphite and / or graphene should roughly coincide; they do not need to coincide perfectly or be perfectly parallel.

[0027] According to some embodiments of this disclosure, as described above, the material of the heating diaphragm manufactured from the raw material, natural graphite or graphene, is graphite, and therefore the heating diaphragm of this disclosure has a high heating temperature and a fast heating rate. Here, the manufactured graphite still exhibits a sheet-like structure, and the planar stretching direction of the sheet-like structure basically coincides with the planar stretching direction of the raw material, natural graphite or graphene. Therefore, it can be said that the sheet-like stretching plane of the heating diaphragm basically coincides with the sheet-like stretching plane of its material, graphite.

[0028] According to some embodiments of this disclosure, the time it takes for the heating diaphragm to reach its maximum heating temperature is 0.1s to 2s, for example, 0.1s, 0.2s, 0.4s, 0.5s, 0.6s, 0.7s, 0.8s, 0.9s, 1s, 1.1s, 1.2s, 1.3s, 1.4s, 1.5s, 1.6s, 1.7s, 1.8s, 1.9s, 2.0s, etc. As is clear from this, the heating rate of the heating diaphragm of this disclosure is fast, allowing it to reach its maximum heating temperature in a short time, and consequently, the heating efficiency of the heating diaphragm is greatly improved.

[0029] According to some embodiments of this disclosure, the heat resistance temperature of the heating diaphragm is 2500°C or higher, for example, 2500°C, 2550°C, 2600°C, 2650°C, 2700°C, 2750°C, 2800°C, 2850°C, 2900°C, 2950°C, 3000°C, etc. As is clear from this, the heat resistance temperature of the heating diaphragm of this disclosure is high, and as a result it can reach high heating temperatures without deteriorating.

[0030] According to some embodiments of the present disclosure, the maximum heating temperature of the heating diaphragm is 500°C to 1700°C. For example, the maximum heating temperature of the heating diaphragm may be 500°C, 550°C, 600°C, 700°C, 800°C, 900°C, 1000°C, 1100°C, 1200°C, 1300°C, 1400°C, 1500°C, 1600°C, 1700°C, etc. As can be clearly seen from this, the heating diaphragm of the present disclosure has a high maximum heating temperature and can reach up to 1700°C. Therefore, it can meet various heating usage requirements of the heating diaphragm, and different power heating diaphragms, such as ultra-low power or ultra-high power, can be obtained.

[0031] According to some embodiments of the present disclosure, the thickness of the heating diaphragm is 0.04 mm to 2 mm. For example, the thickness of the heating diaphragm is 0.04 mm, 0.06 mm, 0.08 mm, 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2.0 mm, etc. The heating diaphragm with the above thickness can meet the requirements of different power levels of the heating diaphragm. In addition, the carbon-based heating diaphragm of the present disclosure has high manufacturability, that is, high production yield and long service life. Furthermore, because the thickness of the above heating diaphragm is thin, it is easy to meet the requirements of lightweight design of the heating diaphragm.

[0032] According to some embodiments of the present disclosure, the density of the heating diaphragm is 0.6 g / cm 3 ~1.8 g / cm 3 . For example, the density of the heating diaphragm is 0.6 g / cm 3 , 0.8 g / cm 3 , 1.0 g / cm 3 , 1.2 g / cm 3 , 1.4 g / cm 3 , 1.5 g / cm 3 , 1.6 g / cm 3 , 1.8 g / cm 3And so on. The above density of the heat-generating diaphragm can meet the different power requirements of the heat-generating diaphragm, and the carbon-based heat-generating diaphragm of this disclosure is highly manufacturable, that is, it has a high production yield and a long service life. Furthermore, by combining the above density and thickness, the power of the heat-generating diaphragm can be flexibly adjusted to meet different power usage requirements.

[0033] According to some embodiments of the present disclosure, the power of the heating diaphragm ranges from 15W to 10000W, for example, 15W, 20W, 40W, 50W, 70W, 100W, 150W, 300W, 500W, 800W, 1000W, 1500W, 3000W, 4500W, 5000W, 6000W, 7000W, 8000W, 9000W, 10000W, etc., thereby enabling the heating diaphragm of the present disclosure to effectively realize heating diaphragms with a wide range of different power levels, i.e., ultra-low power heating diaphragms and ultra-high power heating diaphragms can be realized, meeting the power usage requirements for heating diaphragms under different application conditions.

[0034] According to some embodiments of this disclosure, the carbon content of the exothermic diaphragm is 99% or more. This is advantageous in obtaining an exothermic diaphragm with a high carbon content, i.e., high purity, and consequently a higher performance exothermic diaphragm.

[0035] According to some embodiments of this disclosure, the thermal diffusion coefficient of the heating diaphragm is 50 m 2 / s~450m 2 / s, for example 50m 2 / s, 80m 2 / s, 100m 2 / s, 130m 2 / s, 150m 2 / s, 280m 2 / s, 300m 2 / s, 320m 2 / s, 350m 2 / s, 370m 2 / s, 400m 2The thermal diffusivity coefficient is such that the amount of heat emitted from the heating diaphragm is reduced to less heat being transferred to the outside of the heating cavity by heat conduction. As a result, more heat is concentrated in the heating diaphragm, the heating diaphragm reaches a high temperature, and according to Boltzmann's law, the greater the temperature difference, the greater the radiant energy. Therefore, more heat is transferred into the heating cavity by radiation, and the heat generated in the heating diaphragm is mainly concentrated in the object waiting to be heated. This ensures a good heating rate while preventing excessive heat transfer and large heat loss, thereby improving heating efficiency. In addition, the thermal diffusivity coefficient also helps to extend the service life of the heating diaphragm, and a thermal diffusivity coefficient of 50m 2 If the value is less than / s, the amount of heat transferred by the heat conduction of the heated diaphragm is insufficient, causing the temperature of the heated diaphragm to be too high, failing to meet the lifespan requirements, and the thermal diffusion coefficient is 450m. 2 If the coefficient of thermal diffusivity exceeds 450m², the amount of heat dissipated by thermal conduction increases, reducing radiant energy and decreasing the heating efficiency of the heating diaphragm. Furthermore, a high thermal diffusivity necessitates a higher density of the manufactured heating diaphragm, which is 450m². 2 Densities corresponding to thermal diffusivity coefficients exceeding / s are high and relatively difficult to manufacture in the process. At the same time, the carbon-based exothermic diaphragm of this disclosure is easier and safer to manufacture because the raw materials are readily available and inexpensive, and there is no need for high-temperature graphitization treatment. In addition, the above thermal diffusivity helps to extend the service life of the exothermic diaphragm and improve the manufacturability of the exothermic diaphragm.

[0036] According to some embodiments of the present disclosure, a heat-generating diaphragm made of natural graphite and / or graphene flakes further has temperature self-regulating properties, referring to Figure 10, the heat-generating diaphragm has a critical temperature, and when the temperature of the heat-generating diaphragm is below the critical temperature, the resistance of the heat-generating diaphragm decreases with increasing temperature, and when the temperature of the heat-generating diaphragm is above the critical temperature, the resistance of the heat-generating diaphragm increases with increasing temperature. As will be apparent from this, the heating diaphragm of this disclosure has temperature self-regulating characteristics. Specifically, in the initial stage of heating (i.e., when the temperature of the heating diaphragm is below the critical temperature), the resistance of the heating diaphragm decreases with increasing temperature and the current increases, so the power of the heating diaphragm increases with increasing temperature. Therefore, in this stage, the heating diaphragm can heat up rapidly. After the heating temperature of the heating diaphragm reaches the critical temperature, the resistance of the heating diaphragm increases with increasing temperature and the current decreases, so the power of the heating diaphragm decreases with increasing temperature. Therefore, in this stage, the heating rate of the heating diaphragm slows down, and it slowly and gradually reaches the maximum heating temperature of the heating diaphragm. Due to the temperature self-regulating characteristics of the heating diaphragm, the heating diaphragm can reach the target temperature quickly by accelerating the heating rate in the temperature range below the critical temperature, and when it exceeds the critical temperature, it can reduce melting problems that occur in the process of the heating temperature continuously rising, for example, improving the reliability and stability of the heating diaphragm. Although Figure 10 is merely a temperature-resistance curve diagram of a heating diaphragm in one embodiment, the trend of this curve is representative of the schematic diagram of the temperature-resistance curve of the heating diaphragm of the present disclosure.

[0037] Furthermore, when the temperature of the exothermic diaphragm is below the critical temperature, the heating rate of the exothermic diaphragm is the first heating rate, and when the temperature of the exothermic diaphragm is above the critical temperature, the heating rate of the exothermic diaphragm is the second heating rate, where the first heating rate is greater than the second heating rate. As is clear from this, the exothermic diaphragm of this disclosure has a first heating rate that is fast, and by increasing the heating rate of the exothermic diaphragm, it is possible to reach the critical temperature in a short time, and thereafter, by continuing to heat at a relatively small second heating rate, it is possible to avoid melting problems that occur during the process of the heating temperature rising continuously, and for example, the reliability and stability of the exothermic diaphragm can be improved.

[0038] According to some embodiments of this disclosure, the critical temperature of the exothermic diaphragm is 50°C to 500°C, for example, the critical temperature of the exothermic diaphragm may be 50°C, 80°C, 100°C, 120°C, 150°C, 180°C, 200°C, 230°C, 250°C, 280°C, 300°C, 330°C, 350°C, 370°C, 400°C, 420°C, 450°C, 480°C, 500°C, etc. As is evident from this, the exothermic diaphragm of this disclosure can adjust the specific critical temperature of the exothermic diaphragm within a wide range, a high critical temperature can be selected when the exothermic temperature of the exothermic diaphragm is high, and a low critical temperature can be selected when the exothermic temperature of the exothermic diaphragm is low, thereby better ensuring both a fast exothermic rate and prevention of melting of the exothermic diaphragm.

[0039] In the embodiments of this disclosure, the specific die-cutting of the heating diaphragm can be varied, and those skilled in the art can flexibly design the die-cutting of the heating diaphragm based on the requirements of the actual conditions such as resistance and power of the heating diaphragm. Several die-cutting methods for the heating diaphragm will be described below according to some specific embodiments of this disclosure.

[0040] In some embodiments of the present disclosure, referring to Figure 3, the heating diaphragm includes a plurality of heating units 01 arranged sequentially along its length, with adjacent heating units 01 spaced apart and connected by connecting segments 02. As is evident therefrom, the heating diaphragm of the present disclosure can be cut into various die-cut structures to meet different usage needs. Here, in some embodiments of the present disclosure, referring to Figure 3, the outer periphery wall of the heating unit is formed in an oval or polygonal shape.

[0041] In some embodiments of this disclosure, referring to Figures 3(b), (c), and (i), each heating unit 01 is provided with a perforated hole 03. This allows the installation of the perforated hole to increase the heat dissipation rate of the heating diaphragm and improve the heating rate for items awaiting heating.

[0042] In some embodiments of this disclosure, referring to Figure 4, the heating diaphragm includes a first heating segment S1 and a second heating segment S2 adjacent to each other in the longitudinal direction, the first heating segment S1 includes a plurality of connected heating units 01, the second heating segment S2 includes a plurality of adjacent heating units 01, the dimensions of the heating unit 01 corresponding to the first heating segment S1 are smaller than the dimensions of the heating unit 01 corresponding to the second heating segment S2, for example in Figure 4(a), the length of the heating unit 01 corresponding to the first heating segment S1 and the length of the heating unit 01 corresponding to the second heating segment S2 are the same, but the sizes of their widths d1 and d2 are different, for example in Figures 4(b) and (c), the width of the heating unit 01 corresponding to the first heating segment S1 and the width of the heating unit 01 corresponding to the second heating segment S2 are the same, but the sizes of their lengths d1 and d2 are different. This makes it possible to achieve structural diversification of the heating diaphragm.

[0043] In some embodiments of this disclosure, referring to Figure 5, the first heating segment S1 and the second heating segment S2 are installed offset in the width direction of the heating diaphragm. This makes it possible to diversify the structure of the heating diaphragm.

[0044] In some embodiments of this disclosure, referring to Figures 3(d), (e), (f), (h), (i), and (j), the heating diaphragm includes a number of notches spaced apart along its length. This allows for structural diversification of the heating diaphragm. Furthermore, in some embodiments of this disclosure, referring to Figure 3(i), each notch is defined by folding a portion of the heating diaphragm after it has separated from the rest.

[0045] In some embodiments, as shown in Figure 6, the same heating diaphragm may include multiple types of die-cuts, or it may include the same type of die-cuts with a non-uniform density distribution.

[0046] In other embodiments of this disclosure, the disclosure provides a method for manufacturing the aforementioned exothermic diaphragm. According to embodiments of this disclosure, the method for manufacturing the exothermic diaphragm may be carried out using natural graphite and graphene, respectively, and the specific manufacturing steps are as follows.

[0047] In some examples, the method for manufacturing a heating diaphragm using natural graphite is as follows: S100 includes the steps of providing natural graphite, intercalating it, and obtaining graphite oxide (expandable graphite).

[0048] In this disclosure, since natural graphite is used and there is no need to manufacture it by other processes, the manufacturing process for the exothermic diaphragm can be further simplified and costs can be reduced. If artificial graphite is used, an additional manufacturing process for artificial graphite is required, which significantly increases the cost and time of manufacturing the exothermic diaphragm and reduces production efficiency. Furthermore, when natural flake graphite is used, the single-layer structure of the graphite exhibits a layered structure, so the graphite in the manufactured exothermic diaphragm also exhibits a layered structure, which can improve the concentrated heating effect of the exothermic diaphragm. Moreover, natural flake graphite has large reserves in the Earth's mineral resources, and at the same time, the carbon-based diaphragm material does not require high-temperature graphitization in the manufacturing process and can be produced continuously, thus further improving production efficiency and reducing manufacturing costs. The absence of high-temperature graphitization also improves production safety.

[0049] Furthermore, natural flake graphite is abundant in the Earth's mineral resources, and the exothermic diaphragm material of this disclosure does not require high-temperature graphitization during the manufacturing process and can be produced continuously. This further improves production efficiency and reduces manufacturing costs, and the absence of high-temperature graphitization also improves production safety.

[0050] In some embodiments, the specific method of intercalation treatment may involve intercalating natural flake graphite with an oxide such as concentrated sulfuric acid and / or hydrogen peroxide to obtain expandable graphite.

[0051] S200 is subjected to an expansion treatment to obtain expanded graphite.

[0052] In some embodiments, expandable graphite is placed in an expansion furnace and rapidly expands after a momentary period of high temperature to form vermicular graphite, or expanded graphite. The expansion ratio of the expandable graphite may be 30 to 400 times through the expansion process. In this process, the expansion temperature is 850 to 1200°C and the expansion time is 0.7 to 1.3 seconds.

[0053] S300 expanded graphite is rolled, subjected to a first heat treatment, and cut to obtain an exothermic diaphragm. Different die-cut exothermic diaphragms obtained after cutting can be seen in Figures 3 to 6, and the specific die-cut characteristics are in line with the aforementioned requirements, so a detailed explanation is omitted here.

[0054] Here, there are no specific requirements for the first heat treatment method, and those skilled in the art can employ specific heat treatment methods for obtaining graphite by deoxygenation treatment of graphite oxide in the prior art.

[0055] In this way, by rolling the expanded graphite, it is possible to control the parameter characteristics such as the thickness, density, and thermal diffusivity of the heat-generating diaphragm. The thickness, density, and thermal diffusivity of the heat-generating diaphragm are as described above, and a detailed explanation is omitted here.

[0056] In some examples, the critical temperature of the exothermic diaphragm produced from the above-mentioned natural graphite is 50-200°C. As is clear from this, it is possible to produce an exothermic diaphragm with a lower critical temperature by the above method.

[0057] According to the embodiments of this disclosure, the graphite material heating diaphragm manufactured using the above-mentioned natural graphite increases the heating temperature and speed of the heating diaphragm, thereby contributing to higher temperature heating and more efficient heating. Furthermore, the heating diaphragm of this disclosure uses natural graphite, which is abundant in the Earth's mineral resources. At the same time, the carbon-based diaphragm material does not require high-temperature graphitization during the manufacturing process and does not require production through other processes, enabling continuous production and cost reduction. Overall, the carbon-based diaphragm material has advantages such as a wide range of raw material sources, a simple manufacturing process, excellent product stability, and easy adjustment of performance parameters according to needs, offering significant advantages in terms of reducing product costs, improving product reliability, and expanding product variety. If artificial graphite is used, an additional process for manufacturing artificial graphite is required, which significantly increases the manufacturing cost and time of the heating diaphragm and reduces production efficiency.

[0058] In some examples, the method for manufacturing a heat-generating diaphragm using graphene is as follows: S400, graphene, and additives are mixed and uniformly dispersed to obtain a dispersion.

[0059] In some examples, the graphene used is graphene microparticles, with a planar size of 1 to 100 μm and a specific surface area of ​​30 to 800 m². 2 The graphene flakes are distributed uniformly at a density of / g, making it easy to disperse the graphene flakes as described above.

[0060] In some examples, the additive comprises at least one of carboxymethylcellulose, polyvinyl alcohol, polyethylene glycol, polyacrylic acid compounds, and aqueous polyurethane, and the addition of the above additive can effectively improve the film-forming properties of graphene flakes.

[0061] Furthermore, when expressed as a mass percentage based on the total mass of the dispersion, the mass fraction of the additive is 5% or less, for example, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%. Because the amount of additive used is small, it does not affect the good performance of the manufactured exothermic diaphragm.

[0062] S500 is applied to the dispersion to obtain a dispersion film.

[0063] In some embodiments, there are no specific requirements for the coating method, and those skilled in the art can flexibly select an appropriate coating method based on their actual needs, such as spin coating or spray coating.

[0064] A second heat treatment is performed on the S600 dispersion film to obtain a carbon group initial film.

[0065] In this step, graphene is deoxygenated by a second heat treatment to obtain graphite material. Here, the heat treatment can be carried out in a vacuum or inert gas atmosphere, and the second heat treatment temperature is 1500 to 3000°C. Through the above method, graphite with a high carbon content can be obtained, for example, the carbon content can reach 99% or more.

[0066] S700 carbon matrix is ​​rolled and cut to obtain an exothermic diaphragm. Figures 3 to 6 show the exothermic diaphragms with different die-cuts obtained after cutting. The specific die-cut characteristics are consistent with the requirements mentioned above, so a detailed explanation is omitted here.

[0067] In some examples, the critical temperature of exothermic diaphragms made from graphene flakes is 150-500°C. As is clear from this, it is possible to manufacture exothermic diaphragms with a high critical temperature using the above method.

[0068] According to the embodiments of this disclosure, using graphene as a raw material is advantageous not only for obtaining a heat-generating diaphragm with a high carbon content, but also because the processing process is simple and mature, and the manufacturing cost is not high. The graphene flakes used have excellent thermal conductivity and tensile strength, which in turn contributes to improving the heat generation temperature and mechanical strength of the manufactured heat-generating diaphragm.

[0069] In other embodiments of this disclosure, the disclosure provides a heating tube. According to embodiments of this disclosure, the heating tube includes the aforementioned heating diaphragm. This results in a lighter heating tube, a higher heating temperature, and a faster heating rate. As those skilled in the art will understand, the heating tube possesses all the features and advantages of the aforementioned heating diaphragm, and a detailed explanation is omitted here.

[0070] In some embodiments, referring to Figures 7 (where the S region is a local cross-sectional view of the sleeve), 8, and 9, the heating tube further includes a sleeve 10, the heating diaphragm 20 is placed inside the sleeve 10, and terminals 21 are provided at both ends of the heating diaphragm 20, where the sleeve may be a quartz glass tube or the like.

[0071] In other embodiments of this disclosure, the disclosure provides a heating electric device. According to embodiments of this disclosure, the heating electric device includes the aforementioned heating tube. This results in a rapid heating rate and a high heating temperature for the heating electric device. As will be understood by those skilled in the art, the heating electric device possesses all the features and advantages of the aforementioned heating diaphragm, and a detailed explanation is omitted here.

[0072] According to embodiments of the present disclosure, the heating electrical appliance is an electric oven, microwave oven, steam oven, electric kettle, electric blanket, electric fan, electric heater, bathroom heater / dryer, radiant heater, or disinfection cabinet.

[0073] As those skilled in the art will understand, a heating electrical device includes, in addition to the heating tube, the necessary structure or components for the heating electrical device. For example, in the case of an electric oven, in addition to the heating tube, it includes the necessary structure or components such as a housing, heating space, base, and plug.

[0074] Examples Example 1 A heating diaphragm was manufactured using natural flake graphite. A schematic diagram of the heating diaphragm's structure can be seen in Figure 3(a). The heating diaphragm has a thickness of 0.04 mm, a length of 3 dm, a width of 8 mm, and a density of 1 g / cm³. 3 That is the case.

[0075] Example 2 The difference from Example 1 is that the thickness of the heating diaphragm is 0.1 mm.

[0076] Example 3 The difference from Example 1 is that the thickness of the heating diaphragm is 0.5 mm.

[0077] Example 4 The difference from Example 1 is that the thickness of the heating diaphragm is 1 mm.

[0078] Example 5 The difference from Example 1 is that the thickness of the heating diaphragm is 1.5 mm.

[0079] Example 6 The difference from Example 1 is that the thickness of the heating diaphragm is 2 mm.

[0080] Example 7 The difference from Example 1 is that the length of the heating diaphragm is 2 dm.

[0081] Example 8 The difference from Example 1 is that the length of the heating diaphragm is 6 dm.

[0082] Comparative Example 1 The difference from Example 1 is that the thickness of the heating diaphragm is 0.03 mm.

[0083] Comparative Example 2 The difference from Example 1 is that the thickness of the heating diaphragm is 2.2 mm.

[0084] Comparative Example 3 A metal heating tube core is used, with a length of 3 dm.

[0085] Comparative Example 4 A quartz tube core is used, and its length is 3 dm.

[0086] Example 9 A heat-generating diaphragm was manufactured using graphene flakes. A schematic diagram of the heat-generating diaphragm's structure can be seen in Figure 3(a). The heat-generating diaphragm has a thickness of 0.04 mm, a length of 3 dm, a width of 8 mm, and a density of 1 g / cm³. 3 That is the case.

[0087] Example 10 The difference from Example 9 is that the thickness of the heating diaphragm is 0.1 mm.

[0088] Example 11 The difference from Example 9 is that the thickness of the heating diaphragm is 0.5 mm.

[0089] Example 12 The difference from Example 9 is that the thickness of the heating diaphragm is 1 mm.

[0090] Example 13 The difference from Example 9 is that the thickness of the heating diaphragm is 1.5 mm.

[0091] Example 14 The difference from Example 9 is that the thickness of the heating diaphragm is 2 mm.

[0092] Comparative Example 5 The difference from Example 9 is that the thickness of the heating diaphragm is 0.03 mm.

[0093] Comparative Example 6 The difference from Example 9 is that the thickness of the heating diaphragm is 2.2 mm.

[0094] The mass, maximum heating temperature, heating response time, and power of the heating diaphragm in Examples 1 to 8 and Comparative Examples 1 to 2 were measured, as were the mass, maximum heating temperature, heating response time, and power of the heating tube core in Comparative Examples 3 and 4. The mass, maximum heating temperature, heating response time, and power of the heating diaphragm in Examples 9 to 14 and Comparative Examples 5 to 6 were also measured, and the measurement results are shown in Table 1.

[0095] In Comparative Examples 1 and 5, the thickness of the heating diaphragm is small, resulting in an uneven overall thickness, insufficient manufacturability, and making it impossible to perform test measurements. In Comparative Examples 2 and 6, the thickness of the heating diaphragm is large, making it prone to breakage, insufficient manufacturability, and the production acceptance rate does not meet the manufacturing requirements.

[0096] [Table 1]

[0097] As is clear from the data above, the response time of the heating diaphragm is proportional to the length of the heating diaphragm; the longer the heating diaphragm, the longer the heating response time. Furthermore, as the weight of the heating diaphragm per unit length increases, the heating power of the heating diaphragm gradually improves. As is clear from the comparison with Comparative Examples 3 and 4, the heating response time of the heating diaphragm of this disclosure is extremely short, and because it is lightweight, rapid heating can be achieved, as well as a high heating temperature and a lightweight design for the heating tube.

[0098] Example 15 In Example 4, the heating tubes, halogen tubes, quartz tubes, and metal tubes were each placed in the same oven. The power used to measure all heating tubes was 600W, and the time required for each heating tube to reach 200°C at the center of the oven was measured. See Table 2 for the measurement results.

[0099] [Table 2]

[0100] As is clear from the above examples and comparative examples, the heat-generating diaphragm of this disclosure has a light weight while simultaneously having a high heat-generating temperature, a fast heat-generating rate, and a rapid heating rate.

[0101] The terms “first” and “second” in the specification are used solely for descriptive purposes and should not be understood as indicating or suggesting relative importance or specifying the number of technical features being referred to. Therefore, features designated as “first” or “second” may be explicitly or implicitly defined as including one or more such features. In this description, “multiple” means two or more unless otherwise clearly and specifically defined.

[0102] In this specification, any reference to terms such as “one example,” “several examples,” “exemplary,” “specific example,” or “several examples” means that the specific features, structures, materials, or properties described in such example or example are included in at least one example or example of this disclosure. The exemplary expressions of the above terms in this specification do not necessarily refer to the same example or example. Furthermore, the specific features, structures, materials, or properties described may be combined in appropriate ways in any or more examples or examples. Also, a person skilled in the art may combine or link different examples or examples and features of different examples or examples described herein, provided they are not contradictory.

[0103] Although embodiments of the present disclosure are shown and described above, these embodiments are illustrative and should not be understood as limiting the disclosure. Those skilled in the art can modify, alter, substitute, and transform these embodiments within the scope of the present disclosure.

Claims

1. A heat-generating diaphragm, wherein the raw materials of the heat-generating diaphragm include natural graphite and / or graphene, and the weight of the heat-generating diaphragm with a length of 1 decimeter is 0.02 to 2 g.

2. The heating diaphragm according to claim 1, wherein the heating diaphragm has a sheet-like structure, the graphite and graphene have a sheet-like structure, and the sheet-like stretched plane of the heating diaphragm and the sheet-like stretched plane of the graphite and / or graphene basically coincide.

3. The heating diaphragm according to claim 1, wherein the time it takes for the heating diaphragm to reach its maximum heating temperature is 0.1 s to 2 s.

4. The heat-retaining diaphragm according to claim 1, wherein the heat resistance temperature of the heat-retaining diaphragm is 2500°C or higher.

5. The heating diaphragm according to claim 1, wherein the maximum heating temperature of the heating diaphragm is 500°C to 1700°C.

6. The heating diaphragm according to claim 1, wherein the material of the heating diaphragm is graphite.

7. The heating diaphragm according to claim 1, wherein the power of the heating diaphragm is 15W to 10000W.

8. The heating diaphragm according to claim 1, wherein the heating diaphragm includes a plurality of heating units arranged sequentially along its length, adjacent heating units are spaced apart and connected by connecting segments.

9. The heating diaphragm according to claim 8, wherein each of the heating units is provided with a perforated hole.

10. A method for manufacturing a heating diaphragm according to any one of claims 1 to 9, The steps include providing the aforementioned natural graphite, performing an intercalation treatment thereto to obtain expandable graphite, The steps include: performing an expansion treatment on the expandable graphite to obtain expanded graphite; The process includes the steps of rolling, first heat treatment, and cutting the expanded graphite to obtain the heat-generating diaphragm, Or, The steps include: mixing the graphene and additives to uniformly disperse them and obtaining a dispersion; The steps include applying the dispersion to obtain a dispersion film, The steps include: performing a second heat treatment on the dispersion film to obtain a carbon matrix initial film; A method comprising the steps of rolling and cutting the carbon group initial film to obtain the exothermic diaphragm.

11. A heating tube comprising a heating diaphragm according to any one of claims 1 to 9.

12. A heating electrical appliance, comprising a heating tube as described in claim 11.

13. The heating electrical appliance according to claim 12, wherein the heating electrical appliance is an electric oven, microwave oven, steam oven, electric kettle, electric blanket, electric fan, electric heater, bathroom heater / dryer, radiant heater, or disinfection cabinet.

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