Inner pot and cooking utensils with steam passage structure

Abstract

This application relates to the field of household appliance technology, and particularly to an inner pot and cooking utensil with a steam channel structure. This application provides an inner pot with a steam channel structure, including a pot body. The inner surface of the pot body is provided with a steam channel structure in the shape of biomimetic leaf veins. The steam channel structure includes multiple interconnected grooves, which divide the inner surface into multiple rib units with a forked structure. The geometric shapes of any two adjacent rib units projected vertically onto the inner surface of the pot body are different, and adjacent rib units are separated by the grooves. This application forms steam channels by designing irregularly forked grooves on the surface of the inner pot, dividing the inner surface into polygonal or curved rib units. This design guides the flow of steam during cooking, reduces the possibility of blockage, and helps improve heating uniformity and moisture distribution.

Description

Technical Field

[0001] This application relates to the field of household appliance technology, and in particular to an inner pot and cooking utensil with a water vapor channel structure. Background Technology

[0002] Traditional bottom-heating rice cookers exhibit a significant temperature difference between the bottom and sides of the inner pot during operation. This results in rice at the bottom being overheated, becoming slightly hard or even burnt, while rice on the sides remains relatively soft and moist. Although the later-developed IH technology can achieve relatively more even heating, uneven heating is still prevalent due to various factors such as the material and thickness of the inner pot and the coil layout.

[0003] In the later stages of cooking, a large amount of steam accumulates above the cooking area of ​​the inner pot. Under external cooling conditions, it condenses into water and flows downwards along the side wall of the pot. However, the smooth surface or the textured grooves of the inner pot are often blocked by the expanding rice, preventing the water from flowing evenly along the inner wall to the fully heated bottom. This often results in the rice at the bottom being dry and hard, while the rice on the upper side and surface is soft and mushy, affecting the taste of the rice. Utility Model Content

[0004] The main purpose of this invention is to provide a cooking inner pot and cooking appliance with a water vapor channel structure, which aims to solve the problem of uneven heating and poor taste of rice caused by water vapor accumulation on the surface of the inner pot.

[0005] To achieve the above objectives, this application proposes an inner pot with a water vapor channel structure, including a pot body. The inner surface of the pot body is provided with a water vapor channel structure in the shape of a biomimetic leaf vein. The water vapor channel structure includes multiple interconnected grooves, which divide the inner surface into multiple rib units and have a bifurcated structure. The geometric shapes of any two adjacent rib units projected vertically onto the inner surface of the pot body are different, and adjacent rib units are separated by the grooves.

[0006] In some embodiments, the depth of the groove ranges from 10μm to 100μm, and / or the depth of the groove is distributed in a gradient increasing direction along the side region, the arc transition region to the bottom region of the inner surface, and satisfies: the average depth of the groove in the side region ≤ the average depth of the groove in the arc transition region ≤ the average depth of the groove in the bottom region.

[0007] In some embodiments, the average depth h1 of the side area groove, the average depth h2 of the arc transition area groove, and the average depth h3 of the bottom area groove satisfy: h1≤h2≤h3<1.5h1.

[0008] In some embodiments, the width of the groove decreases gradually along the direction from the side area, the arc transition area to the bottom area of ​​the inner surface, and satisfies the following condition: the average width of the groove in the side area ≥ the average width of the groove in the arc transition area ≥ the average width of the groove in the bottom area.

[0009] In some embodiments, the width of the groove ranges from 0.01mm to 4mm, and / or the average width D of the groove in the side region... e1 The average width D of the groove in the arc transition area e2 The average width D of the groove in the bottom area e3 Satisfies: 1.8D e3 >D e1 ≥D e2 ≥D e3 .

[0010] In some embodiments, the cross-section of the rib unit along any direction is a continuous arc-shaped surface, and its top height is greater than the height of its two side edges.

[0011] In some embodiments, the inner surface is a metal layer, and the material of the metal layer includes at least one of iron, stainless steel, aluminum, copper, and titanium; and / or, the metal substrate layer includes a multilayer structure.

[0012] And / or, the surface of the metal layer includes a microstructure, the surface of the water vapor channel structure includes a nanostructure, and the rib unit covers at least a portion of the microstructure to form a micro / nano structure.

[0013] On the other hand, this application also provides a cooking appliance, including the inner pot with the above-mentioned steam channel structure, and a heating device that cooperates with the inner pot.

[0014] In summary, the inner pot and cooking appliance with a steam channel structure proposed in this application form steam channels by designing irregularly branched grooves on the surface of the inner pot, dividing the inner surface into irregularly shaped and distinct raised rib units. This design guides the flow of steam during cooking, while reducing the possibility of blockage, and helps improve the uniformity of heating and moisture distribution. Such a structure has a positive impact on improving the taste and quality of rice. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the inner surface morphology of the inner pot in some embodiments of this application;

[0017] Figure 2 This is a schematic diagram of the water vapor flow path on the inner surface of the side wall of the inner pot in some embodiments of this application;

[0018] Figure 3 This is a schematic diagram of the water vapor flow path on the inner surface of the bottom of the inner pot in some embodiments of this application;

[0019] Figure 4 This is a schematic diagram of the width of the groove in the water vapor channel structure of some embodiments of this application (De in the figure represents the width);

[0020] Figure 5 These are 3D topographic images of the inner surface of the inner pot in some embodiments of this application;

[0021] Figure 6 This is a cross-sectional view of the inner surface of the inner pot in some embodiments of this application;

[0022] Figure 7 This is a schematic diagram of moisture sampling of rice at nine points according to an embodiment of this application.

[0023] 1-Groove; 2-Rib unit. Detailed Implementation

[0024] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of the embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0025] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0026] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0027] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0028] In existing technologies, traditional rice cookers use bottom heating or electromagnetic heating, but due to differences in the material, thickness, and coil layout of the inner pot, uneven heating is a problem. In the later stages of cooking, a large amount of water vapor accumulates in areas without rice. When it condenses and flows along the inner wall, it is easily blocked by the expanding rice, resulting in insufficient moisture at the bottom, making it dry and hard, while excessive moisture at the top, making it wet and soft, affecting the uniformity of the taste.

[0029] To address these issues, a structure is needed to improve the water vapor flow path, prevent localized blockages, and enhance flow guidance efficiency. Analysis of the natural flow characteristics of condensate reveals that regularly arranged independent grooves are prone to blockage due to their singular flow path, while smooth surfaces lack flow guidance structures.

[0030] Based on this, this application proposes an inner pot with a water vapor channel structure, including a pot body, the inner surface of which is provided with a water vapor channel structure in the shape of biomimetic leaf veins; such as Figure 1As shown, the water vapor channel structure includes multiple interconnected grooves 1, which divide the inner surface into multiple rib units 2 and have a bifurcated structure; wherein, the geometric shapes of any two adjacent rib units 2 in the vertical direction of the inner surface of the pot are different, and adjacent rib units 2 are separated by grooves 1.

[0031] Among them, such as Figure 1 As shown, the water vapor channel structure refers to a three-dimensional flow-guiding network covering the inner surface, composed of interconnected grooves. It can be formed using laser etching or stamping processes to establish multi-directional water vapor transport paths. The biomimetic leaf vein-shaped water vapor channel structure refers to a three-dimensional structure that simulates the branching morphology of plant leaf veins, which can be achieved through embossing or laser processing. For example... Figure 2 , Figure 3 As shown, the grooves extend along irregular paths, simulating the natural diffusion trajectory of liquid. Specifically, fractal geometry algorithms can be used for path planning to avoid the flow direction limitations caused by straight grooves. The bifurcation structure refers to the branching connections generated during the extension of the grooves, enhancing the connectivity between different areas.

[0032] The inner surface of the pot is divided into groups of raised ribs (rib unit groups) of various shapes by water vapor channels. "The geometric shapes of the vertical projections of any two adjacent raised rib units are different" means that when viewed from a direction perpendicular to the pot surface, the contours of any two adjacent raised rib units on a two-dimensional plane are not repeated. Here, the vertical direction refers to the direction of the normal along any point on the pot surface. In three-dimensional geometry, the normal is a straight line tangent to a given curve or surface and perpendicular to the tangent. For example, raised rib A may have a branching, tree-like contour; its adjacent raised rib B may have an earthworm-like contour; and its adjacent raised rib C may have an irregular polygonal island-like contour. Thus, the shape and spatial arrangement of the raised rib units exhibit an irregular, three-dimensional distribution. This arrangement breaks the regularity of existing traditional matrix textures (such as dot matrix, parallel stripes, or other regular intervals and sizes), forming a disordered network structure similar to plant leaf veins. Figure 1 As shown in the bright areas, the raised rib units also feature an irregular, natural arrangement. A raised rib unit refers to an independent area formed by grooves; it can be designed as a polygonal or wavy planar projection, using geometric differences to reduce the contact area between the rice and the pot wall.

[0033] The interconnected network of grooves creates a capillary effect, guiding condensate to the bottom. The branching structure allows water to choose alternative paths when encountering local resistance, preventing flow interruption caused by blockage in a single groove. The curved edges of the raised ribs reduce linear contact with the rice, lowering the probability of sticking. When water vapor condenses on the sidewalls, the irregular network of grooves provides multidirectional flow options, automatically adjusting the water flow distribution based on temperature differences to achieve a dynamic balance between moisture replenishment at the bottom and sides.

[0034] Compared to existing technologies, traditional solutions use independent straight grooves or smooth surfaces, resulting in a single water flow path that is prone to clogging. This solution establishes redundant flow paths through a biomimetic irregular groove network, and the bifurcated structure enhances the moisture regulation capability between regions. The polygonal rib units increase the heated area while reducing surface adhesion, achieving a more efficient dynamic moisture balance.

[0035] Through the above technical solution, this application can better guide condensate to diffuse evenly along multi-directional paths, avoiding localized water accumulation or loss. The connectivity of the groove network ensures continuous water vapor flow, the branched structure improves adaptability to temperature distribution differences, and the raised rib units reduce the impact of rice sticking on water vapor channels, thereby improving heating uniformity and making the taste of rice more consistent throughout.

[0036] In some embodiments, the depth of the groove ranges from 10μm to 100μm. The depth of the groove refers to the vertical distance between the bottom of the groove and the inner surface of the inner pot. When the groove depth is within this threshold range of 10μm-100μm, the synergistic effect of surface tension and gravity causes the condensate to diffuse in a predetermined direction. On the one hand, the groove depth affects the uniformity of water distribution. Too shallow a depth obstructs the flow of water vapor through the channel, preventing the formation of a better rapid flow path; while too deep a channel prevents rapid water vapor flow, easily causing local stagnation and affecting the uniformity of water distribution in the rice. On the other hand, the groove depth also affects the stickiness of rice on the surface and ease of cleaning. Too deep a channel makes it easy for rice to sink into it, accumulating dirt and making it difficult to clean; while too shallow a channel increases the contact area between the rice and the pot wall, failing to provide good support and making it easy for rice to stick.

[0037] In some preferred embodiments, the depth of the groove ranges from 30 μm to 60 μm. When the groove depth is in the range of 30 μm to 60 μm, the fluid dynamics characteristics within the channel and the surface morphology form a better synergistic effect.

[0038] In some embodiments, the depth of the groove increases gradually along the direction from the side area of ​​the inner surface, the arc transition area to the bottom area, and satisfies the following: the average depth of the groove in the side area ≤ the average depth of the groove in the arc transition area ≤ the average depth of the groove in the bottom area.

[0039] The average depth of the groove refers to the arithmetic mean of measurements taken at different locations along the length of the groove. The side area refers to the entire vertical or near-vertical cylindrical wall surface of the inner pot, from the bottom to the opening. It can be formed into a continuous curved surface using a stamping process; its shallow groove structure helps control water flow speed and prevents excessive evaporation. The arc transition area refers to the transitional curved surface connecting the side and bottom. A gradual curvature can be formed using a spinning process; a medium-depth groove maintains water flow continuity. The bottom area refers to the flat or spherical area at the bottom of the inner pot that directly contacts the heating element. The deepest groove is formed using laser etching to collect and store condensate flowing there. The gradient increasing distribution indicates that the groove depth exhibits a non-uniform spatial variation; depth differences can be achieved through segmented processing or parametric molds.

[0040] When condensation forms on the surface of the inner pot, the shallower grooves on the sides preferentially guide the water flow to form a thin liquid film, which then flows downwards under gravity. As the water flows through the arc-shaped transition area, the medium-depth grooves maintain flow continuity through capillary action, preventing the liquid film from breaking. Upon reaching the bottom area, the deepest grooves form a water storage space, allowing the water to evaporate fully in the high-temperature zone. This depth gradient avoids insufficient water retention time in the side areas due to excessively deep grooves, while also preventing flow resistance in the bottom area due to excessively shallow grooves, thus achieving an orderly migration of water from the top to the heating zone. This design establishes a depth gradient relationship, matching the groove structure to the thermodynamic conditions of each area, forming a water vapor channel that conforms to the laws of fluid dynamics.

[0041] Through the above technical solution, this application further improves the distribution of condensate on the surface of the inner pot, enabling water to flow directionally to the high-temperature area along a predetermined path. The side area reduces residual moisture to prevent the upper rice from becoming too wet, the bottom area enhances water storage capacity to prevent the rice from becoming too dry, and the arc-shaped area maintains stable water flow to prevent liquid film rupture, ultimately improving the overall uniformity of the rice's texture.

[0042] In some embodiments, the average depth h1 of the side area groove, the average depth h2 of the arc transition area groove, and the average depth h3 of the bottom area groove satisfy: h1≤h2≤h3<1.5h1.

[0043] The average depth h1 of the grooves in the side area refers to the average depth of the grooves in the side area of ​​the inner pot. This can be achieved through laser engraving or chemical etching processes, creating an initial condensation path on the side wall while preventing excessive depth from causing rice to stick together or reducing structural strength. The average depth h2 of the grooves in the arc transition area refers to the average depth of the grooves in the transition area between the inner pot's side wall and bottom. This can be achieved using gradual processing parameters to enhance the water flow guidance in the curved area and prevent water vapor retention. The average depth h3 of the grooves in the bottom area refers to the average depth of the grooves in the bottom area of ​​the inner pot. This can be achieved through zoned control of the processing depth, accelerating the transport of moisture to the high-temperature area. Furthermore, by limiting the ratio of h3 to h1 to no more than 1.5, excessive depth differences can prevent capillary imbalance.

[0044] A gradient distribution of groove depth is used to establish a continuous flow path from the sidewall to the bottom of the pot. The shallower grooves in the side areas allow condensate to initially collect on the sidewall without affecting the moisture content of the rice. The transition depth in the arc-shaped transition area accelerates the water flow in the curved area, while the greater depth in the bottom area promotes contact between moisture and the high-temperature area. The depth ratio of each area is strictly controlled to both facilitate the increasing gradient of capillary force and avoid water flow turbulence or structural weakness caused by abrupt changes in local depth.

[0045] This solution achieves dynamic balance of water flow through regionalized depth gradients and upper limit constraints, enabling precise control of water diversion capacity in different areas of the inner pot. This further reduces the difference in moisture content between the bottom and sidewall areas of the rice, resulting in a more uniform texture. Simultaneously, the limited depth ratio avoids problems such as turbulent flow or reduced structural strength caused by excessive local depth, thus improving the long-term reliability of the inner pot.

[0046] In some embodiments, the width of the groove decreases gradually along the direction from the side area of ​​the inner surface, the arc transition area to the bottom surface area, and satisfies the following condition: the average width of the groove in the side area is ≥ the average width of the groove in the arc transition area is ≥ the average width of the groove in the bottom surface area.

[0047] In this technical solution, such as Figure 4 As shown, the width of the groove is defined as follows: when fluid flows in a channel of complex shape, a certain channel region is equivalent to a circular pipe in terms of flow characteristics, and the diameter of this assumed circular pipe is the width of the groove. Figure 4 (De in the text). Gradient decreasing distribution refers to the groove width gradually decreasing as it extends from the side region to the bottom region. This can be achieved by designing a stepped width for the groove during mold machining or by adjusting the toolpath segment by segment using CNC engraving technology. This distribution adapts to differences in fluid flow characteristics by adjusting the width ratio of different regions.

[0048] The groove width in the bottom region is set to a minimum, the groove width in the arc transition region is slightly larger than that in the bottom region, and the groove width in the side region is the largest, forming a flow acceleration zone. During the flow of condensate, the change in width gradient leads to differences in fluid pressure distribution, driving the water flow from the side region to the bottom region. The decreasing width distribution of the grooves further enhances fluid mixing through turbulence, avoids local stagnation, and optimizes the flow path to reduce resistance.

[0049] The design of water vapor channels with varying groove widths allows for better water vapor flow. The main reasons for this include:

[0050] (1) Turbulence effect: Channels with varying widths can cause turbulence in the fluid during flow. This turbulence can increase the mixing degree of the fluid and reduce the residence time of the fluid in the channel, thereby improving the flowability.

[0051] (2) Pressure change: The change in width will cause uneven pressure distribution in the channel, and the fluid will flow from the high pressure area to the low pressure area. This pressure difference can promote the flow velocity of the fluid.

[0052] (3) Reduce blockage: Channels of varying widths can reduce fluid accumulation in a specific area, thus lowering the risk of blockage;

[0053] (4) Flow path optimization: The curved and width-varying channel is similar to the flow height of natural water systems, resulting in the optimal flow path and the minimum flow resistance.

[0054] Traditional inner pots typically have uniformly or randomly distributed grooves, failing to create a directional pressure gradient. This can cause condensate to stagnate on the sides under gravity. A groove with a decreasing gradient, however, works synergistically with pressure difference and turbulence, allowing water to flow more efficiently towards the bottom, reducing imbalances in water distribution caused by groove blockage or uneven flow resistance. Through this technical solution, this application creates a groove structure with directional flow guidance on the inner pot surface. This allows condensate to be quickly guided to the bottom heating area under the combined action of gravity and pressure difference, preventing water stagnation or channel blockage. This further improves the temperature uniformity across different areas of the inner pot, reducing the phenomenon of dry, hard rice at the bottom and wet, soft rice on the sides.

[0055] In some embodiments, the width of the groove ranges from 0.01mm to 4mm.

[0056] This technical solution limits the width of the grooves on the inner pot surface to 0.01mm-4mm. This width range allows the grooves to form a discontinuous, multi-scale capillary network. The width gradient induces local turbulence, reducing fluid retention; simultaneously, the discrete size distribution reduces the possibility of the grooves being completely blocked by rice particles. The lower limit of 0.01mm is close to the size of water molecule clusters, enhancing surface adsorption and driving condensate to extend along the sidewalls; the upper limit of 4mm avoids excessively wide channels that weaken the capillary effect, maintaining the guiding effect of liquid surface tension. The multi-scale structure works together to guide the entire process from steam adsorption to water droplet confluence. The groove width-to-depth ratio constrains the contact area. The 0.01mm groove width limits the depth to which rice grains sink, while the 4mm upper limit avoids the formation of excessively large pits that accumulate rice grains, and the surface ribs still provide physical support points, weakening the adhesion between rice grains and the substrate. This size range, through the coupling effect of fluid mechanics and surface morphology, optimizes the robustness of the water transport path, improving heating uniformity while reducing cleaning difficulty. The width threshold setting takes into account capillary effect, gravity flow and anti-clogging requirements, forming an adaptive liquid transport network.

[0057] In some embodiments, the width of the groove ranges from 0.2mm to 2mm.

[0058] Excessively narrow grooves are easily blocked by tiny particles, weakening their guiding effect; excessively wide grooves struggle to maintain liquid surface tension, reducing capillary effects and increasing the probability of rice grains getting trapped. This width range constructs a multi-stage synergistic fluid transport system: sub-millimeter grooves (0.2mm level) drive liquid film extension through capillary forces, while millimeter-level grooves (2mm level) provide a low-resistance path for gravity-driven flow. Width gradient variations induce self-organized fluid flow, promoting uniform water film coverage; discrete size distribution disrupts the geometry of blockage formation and limits the contact depth between rice grains and the bottom of the grooves. This size range optimizes moisture transport efficiency through the synergy of a capillary-gravity dual-drive mechanism and an anti-blocking morphology design. The width threshold balances liquid adsorption force, flow flux, and anti-sticking requirements, forming a dynamically adaptable guiding network, thereby further improving heating uniformity and surface cleaning properties.

[0059] In some embodiments, the average width D of the side region groove e1 The average width D of the groove in the arc transition area e2 The average width D of the groove in the bottom area e3 Satisfies: 1.8D e3 >D e1 ≥D e2 ≥D e3 .

[0060] As condensate flows downwards along the inner pot's sidewall, the wider grooves on the side reduce fluid resistance and prevent stagnation on the vertical wall. Upon entering the arc-shaped transition area, the stepped reduction in groove width gradually accelerates the flow while preventing turbulence caused by abrupt changes in cross-section. The narrowest groove width at the bottom enhances water penetration through capillary action, while preventing rice grains from entering and clogging the grooves during boiling. Maintaining structural strength, the 1.8-fold width ratio achieves a balance between fluid dynamics and mechanical stability. This design considers both strength requirements and performance optimization, ensuring the overall structure is robust while promoting efficient fluid flow.

[0061] In some embodiments, the cross-section of the rib unit along any direction is a continuous arc-shaped surface, and its top height is greater than the height of its two side edges.

[0062] Please see Figure 5 , Figure 5 The three-dimensional morphology of the inner surface of the inner pot is shown. Along... Figure 5 The cross-sectional shape of the section cut by the horizontal line of the central axis is as follows Figure 6 As shown, "the cross-section of the rib unit along any direction is a continuous arc-shaped surface" refers to the smooth transition of the rib edges. Traditional inner pot rib structures often employ sharp-edged geometric shapes, with sharp edges prone to stress concentration points. During cooking, rice grains easily become stuck in the recessed areas of these edges, forming mechanical locks and increasing adhesion; simultaneously, the sharp edges experience localized high shear stress during cleaning and wiping, accelerating surface wear and affecting structural durability. This application eliminates geometric abrupt changes by using a continuous arc-shaped surface, establishing a smooth stress gradient distribution. The continuous change in curvature causes elastic slippage rather than embedding of rice grains upon contact, reducing the probability of mechanical interlocking; the arc shape guides fluid flow tangentially, reducing cleaning resistance. The curved surface uniformly distributes external loads, suppressing material fatigue caused by localized stress concentration. The top height of the rib unit's cross-section is greater than the height of its two side edges, which here means that, as... Figure 6 As shown, the cross-section of the convex rib unit exhibits an arc-shaped morphology, high in the middle and low on both sides. Observing its interface from any direction with a transverse cross-section, a distinct mountain-like morphology is visible. The mountain-like arc-shaped cross-section establishes a three-dimensional curvature gradient: the larger radius of curvature at the top forms a low-adhesion contact zone, while the continuous contraction of curvature at the two side edges enables directional flow of the droplet. The height difference induces a capillary pressure difference, accelerating the convergence of the liquid film towards the groove; the stress distribution on the curved surface exhibits self-attenuation characteristics, suppressing local plastic deformation.

[0063] In some embodiments, the inner surface is a metal layer, and the material of the metal layer includes at least one of iron, stainless steel, aluminum, copper, and titanium.

[0064] The inner pot can be a single-layer metal material, a composite structure of multiple metal materials, or a composite material of various metal materials. Its inner surface is a metal layer, and a water vapor channel structure is set on the inner surface of the inner pot. The metal layer refers to the material layer covering the surface of the inner pot, which can be achieved using stamping, casting, or composite rolling processes to improve the thermal conductivity and structural strength of the inner pot. The metal layer achieves a balance between thermal conductivity and corrosion resistance through material selection. For example, iron balances cost and heat capacity, while aluminum accelerates heat diffusion. The material includes at least one of iron, stainless steel, aluminum, copper, and titanium, referring to the composition of the metal layer. It can be achieved using a single metal or a composite of multiple metals. For example, an aluminum and stainless steel composite layer balances thermal conductivity and oxidation resistance, while titanium alloys reduce weight. Different metal combinations can be used to specifically adjust the heat conduction rate and temperature distribution uniformity.

[0065] Specifically, the metal layer rapidly transfers heat to all areas of the inner surface through its thermal conductivity, reducing localized overheating or temperature lag caused by insufficient thermal conductivity of the material. For example, the high thermal conductivity of aluminum allows heat to quickly diffuse to the sides and bottom, preventing excessive temperature differences between the bottom and sidewalls; the combination of copper and iron can reduce thermal inertia while maintaining high thermal conductivity, making the temperature response more sensitive. When a temperature gradient forms on the inner surface, the thermal conductivity of the metal layer promotes the downward flow of condensate along the grooves, preventing excessive moisture accumulation due to low sidewall temperatures.

[0066] In some specific embodiments, the inner surface can use aluminum as the base material and be laminated with a stainless steel layer. The high thermal conductivity of aluminum enables rapid heat transfer, while the stainless steel layer improves corrosion resistance. Alternatively, a titanium alloy can be used as the metal layer to maintain structural stability at high temperatures and reduce the impact of thermal deformation on the water vapor channel structure.

[0067] The material properties of the metal material in this technical solution create a coupled enhancement effect with the water vapor channel structure, achieving synergistic optimization in thermodynamics, interfacial chemistry, and mechanical durability. Through this technical solution, this application can improve the overall thermal conductivity of the inner pot by optimizing the material of the metal layer, reducing the temperature difference between the bottom and sidewalls, and minimizing variations in rice texture caused by uneven thermal conductivity. Simultaneously, the thermal response characteristics of the metal layer promote stable flow of condensate along the grooves, preventing excessive condensate accumulation on the sidewalls due to low temperatures, ultimately improving the uniformity of rice texture.

[0068] In some embodiments, the metal substrate layer includes a multilayer structure, i.e., a multilayer metal composite structure, such as a steel-aluminum-steel three-layer composite, a steel-aluminum two-layer composite, or a steel-aluminum-titanium combined inner pot structure. These materials or composite forms can be selected and applied according to actual needs.

[0069] In some embodiments, the surface of the metal layer includes a microstructure, the surface of the water vapor channel structure includes a nanostructure, and the rib unit covers at least a portion of the microstructure to form a micro / nanostructure.

[0070] The nanostructure on the surface of the water vapor channel structure is formed by a layer of nanoparticles, including nanomaterials such as silicon nanocrystals. Specifically, silicon nanoparticles are randomly distributed on the biomimetic leaf vein texture surface (the water vapor channel structure on the surface of the metal substrate layer) with a micron-level rough structure to form a rough surface with micron-nano interlocking micro and nano structures, further improving the hydrophobic properties of the original water vapor channel structure surface. In addition, the silicon crystal layer can act as a "root" on the surface of the metal substrate layer, providing an anchor point for a strong bond between the metal substrate layer and the low surface energy hydrophobic material layer (especially the ceramic layer or the silicon-oxygen bonded material layer).

[0071] On the other hand, this application also provides a cooking appliance comprising the aforementioned inner pot with a steam channel structure, and a heating device that cooperates with the inner pot. The cooking appliance provided by this technical solution, by incorporating the inner pot found in any of the above embodiments, possesses all of the aforementioned beneficial effects.

[0072] In some embodiments, the cooking appliance is a rice cooker, an electric pressure cooker, or an electric slow cooker.

[0073] The following description is based on specific embodiments.

[0074] Example 1

[0075] This embodiment provides an inner pot made of a composite material of 304 stainless steel and aluminum alloy. The inner surface of the inner pot is made of 304 stainless steel, and is press-formed into a water vapor channel structure and then mechanically polished. The water vapor channel includes interconnected grooves extending along irregular paths (such as fractal tree branches). The grooves divide the inner surface into multiple rib units, and adjacent rib units are separated by the grooves. The water vapor channel structure is divided into three regions (side region, arc transition region, and bottom region), wherein the average depth of the grooves in the side region is h1 = 35 μm, the average depth of the grooves in the arc transition region is h2 = 38 μm, and the average depth of the grooves in the bottom region is h3 = 40 μm; the average width D of the grooves in the side region is... e1 =2mm, the average width D of the groove in the arc transition area e2 =1.5mm, the average width D of the groove in the bottom area e3 =1.3mm.

[0076] Example 2

[0077] This embodiment provides an inner pot, which differs from Embodiment 1 in that the average depth and average width parameters of the side area groove, the arc transition area groove, and the bottom area groove are the same. The average width of the three area grooves is 1.5 mm, and the average depth of the three area grooves is 40 μm.

[0078] Comparative Example 1

[0079] This comparative example provides an inner pot, which differs from Example 1 in that the inner surface of this inner pot has no water vapor channel structure and is a smooth, polished surface.

[0080] Comparative Example 2

[0081] This comparative example provides an inner pot, which differs from Example 1 in that the water vapor channel on the inner surface of the inner pot has a regular concave-convex structure, and the designed protrusion dot matrix is ​​a square grid. The height of the protruding square grid is 40μm, the side length is 1mm, and the spacing between the squares is 0.5mm, forming a longitudinally and transversely connected groove channel.

[0082] Performance testing

[0083] To verify the progressiveness of the embodiments of this application, the inner pots of the embodiments and comparative examples were subjected to the following tests:

[0084] 1. Moisture Deviation Test

[0085] (1) Instruments and equipment

[0086] Electronic balance: accuracy 0.0001g, measuring range 10mg-220g.

[0087] Forced-air drying oven: Temperature range: 10℃-250℃, power 2450W, voltage 220V / 50Hz.

[0088] Glass desiccant: Contains effective desiccant.

[0089] Flat weighing bottles made of aluminum or glass.

[0090] (2) Detection steps

[0091] Take a clean, flat aluminum or glass weighing bottle and place it in a drying oven at 101℃~105℃, with the cap tilted against the side of the bottle. Heat for 1.0 hour, remove and seal, then cool in a desiccator for 0.5 hours. Weigh the bottle and repeat the drying process until the difference between two weighings does not exceed 2mg, indicating constant weight. Record the mass as m3. Cook rice according to a specific cooking process, immediately open the lid, and... Figure 7As shown in the diagram, take nine pieces of rice, 1-2 cm from the edge of the pot. These nine points are arranged in a three-row, three-column pattern, with equal spacing between the rows. The two outer columns (1, 4, 7 and 3, 6, 9) are all 1-2 cm from the side of the pot, and the middle column (2, 5, 8) is located on the central axis of the inner pot. Weigh 3g of rice from each point (accurate to 0.0001g).

[0092] Immediately after sampling, cap the bottle and weigh it accurately, which is m1. Place the weighing bottle in a drying oven at 101℃~105℃ with the cap tilted against the side of the bottle. After drying for 2h~4h, cap it and take it out. Place it in a desiccator to cool for 0.5h and weigh it. Repeat the above operation until the difference between the two weights does not exceed 2mg, which is constant weight. Record the weight as m2.

[0093] Note: In the final calculation, the last constant weight value shall be used.

[0094] (3) Calculation

[0095] Calculate the moisture content of cooked rice using Formula I.

[0096]

[0097] In Formula I:

[0098] X4 — Moisture content of cooked rice, in percentage (%);

[0099] m1 — the mass of the weighing bottle and the sample, in grams (g);

[0100] m2 — the mass of the weighing bottle and the sample after drying, in grams (g);

[0101] m3 — the mass of the weighing bottle, expressed in grams (g).

[0102] Calculate the moisture deviation of cooked rice according to Formula II.

[0103] R = X max -X min (Formula II)

[0104] In Formula II:

[0105] R – Moisture deviation, expressed as a percentage (%);

[0106] X max —Maximum moisture content of cooked rice, expressed as a percentage (%);

[0107] X min —Minimum moisture content of cooked rice, expressed as a percentage (%);

[0108] When the moisture content is ≥1%, the calculation result is retained to three significant figures; when the moisture content is <1%, the result is retained to two significant figures.

[0109] (4) Results Comparison

[0110] Table 1. Moisture deviation test results of Examples 1 and 2 and Comparative Examples 1 and 2

[0111] Example 1 2.18 A Example 2 3.56 A Comparative Example 1 8.15 C Comparative Example 2 5.93 B

[0112] Note: The rating standards for moisture deviation are as follows: Grade A: ≤5%; Grade B: 5%-8%; Grade C: 8%-12%; Grade D: 12%-15%.

[0113] As shown in Table 1, the inner pot with water vapor channel texture (Examples 1 and 2) can achieve better water uniformity than the smooth inner pot (Comparative Example 1) and the inner pot with regular concave and convex structure (Comparative Example 2). In particular, the channel structure with different texture parameters in different parts (Example 1) can further accelerate the flow and distribution of moisture, and achieve the best water uniformity.

[0114] 2. Rice cooking test

[0115] The non-stick performance of rice was tested according to the test requirements of GB T32095.2-2015 Non-stick and Abrasion Resistance Test Specification (Non-stick). A uniform rice cooker, rice type and water volume were used. The rice was cooked according to the water level line. After keeping it warm for 10 minutes, the rice was inverted and the remaining rice was weighed and scooped out with a rice scoop.

[0116] The test results are as follows:

[0117] Table 2

[0118] Example 1 63.8 Very few rice grains remain Example 2 72.4 A small amount of rice grains remained Comparative Example 1 156.3 clumps of rice grains adhere Comparative Example 2 81.5 A small amount of rice grains remained

[0119] Note: The rating criteria for non-stickiness are as follows:

[0120] Level 1: All rice grains fall off; Level 2: Rice weight ≤ 50g; Level 3: 50g < Rice weight ≤ 100g; Level 4: Rice weight > 100g.

[0121] As shown in Table 2, the non-stick level of the textured Example 1 and Comparative Example 2 is level three, while the non-stick level of the smooth Example 1 is level four. The uneven structure can store a certain amount of moisture on the surface, which can help to lift the rice grains and has a partial anti-sticking effect. In terms of easy cleaning, the biomimetic irregular channel structure used in Example 1, compared with the regular matrix structure, can prevent rice grains from sticking together at specific locations. The regular matrix structure of Comparative Example 2 may cause rice grains to form a "bridging" phenomenon at certain points, thereby increasing the risk of adhesion. The irregular structure can more evenly disperse the adhesion force, achieving better anti-sticking and easy cleaning effects.

[0122] The above are merely preferred embodiments of the present utility model and do not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. An inner pot with a water vapor channel structure, characterized in that, The device includes a pot body, the inner surface of which is provided with a water vapor channel structure in the shape of a biomimetic leaf vein; the water vapor channel structure includes a plurality of interconnected grooves, the grooves dividing the inner surface into a plurality of rib units and having a bifurcated structure; wherein, the geometric shapes of any two adjacent rib units in the vertical direction of the inner surface of the pot body are different, and adjacent rib units are separated by the grooves.

2. The inner pot as described in claim 1, characterized in that, The depth of the groove ranges from 10μm to 100μm, and / or the depth of the groove increases gradually along the direction from the side area, the arc transition area to the bottom area of ​​the inner surface, and satisfies the following: the average depth of the groove in the side area ≤ the average depth of the groove in the arc transition area ≤ the average depth of the groove in the bottom area.

3. The inner pot as described in claim 2, characterized in that, The average depth h1 of the groove in the side area, the average depth h2 of the groove in the arc transition area, and the average depth h3 of the groove in the bottom area satisfy: h1≤h2≤h3<1.5h1.

4. The inner pot as described in claim 1, characterized in that, The width of the groove decreases gradually along the side area, the arc transition area and the bottom area of ​​the inner surface, and satisfies the following: the average width of the groove in the side area is ≥ the average width of the groove in the arc transition area is ≥ the average width of the groove in the bottom area.

5. The inner pot as described in claim 4, characterized in that, The width of the groove ranges from 0.01mm to 4mm, and / or the average width D of the groove in the side region. e1 The average width D of the groove in the arc transition area e2 The average width D of the groove in the bottom area e3 Satisfies: 1.8D e3 >D e1 ≥D e2 ≥D e3 .

6. The inner pot as described in claim 1, characterized in that, The cross-section of the rib unit along any direction is a continuous arc-shaped surface, and its top height is greater than the height of its two side edges.

7. The inner pot as described in claim 1, characterized in that, The inner surface is a metal layer, and the material of the metal layer includes at least one of iron, stainless steel, aluminum, copper, and titanium; and / or, the metal substrate layer includes a multilayer structure. And / or, the surface of the metal layer includes a microstructure, the surface of the water vapor channel structure includes a nanostructure, and the rib unit covers at least a portion of the microstructure to form a micro / nano structure.

8. A cooking utensil, characterized in that, The invention comprises an inner pot having a steam channel structure as described in any one of claims 1 to 7, and a heating device that cooperates with the inner pot.

Images