An electric fan and a household appliance

Abstract

The application relates to an electric fan, comprising: a fixed assembly having a base, a stator and a printed circuit board, the base having a first end face of flat configuration; a rotating assembly having a rotating shaft supported on the base and a rotor, the rotor having a second end face of flat configuration, the first end face and the second end face being opposite along an axial direction, the base having two first annular walls extending from the first end face towards the second end face, the rotor having a second annular wall extending from the second end face towards the first end face, the first annular walls and the second annular wall being arranged alternately and spaced apart in a radial direction and partially overlapping each other in the axial direction, a labyrinth structure having a winding flow path being formed by the first annular walls and the second annular wall, an installation space being enclosed by the labyrinth structure, the stator and the printed circuit board being arranged in the installation space. The application also relates to a household appliance. The waterproof and dustproof performance can be effectively improved without significantly increasing the manufacturing and assembly precision requirements.

Description

Technical Field

[0001] This application relates to the technical field of household appliances, and in particular to an electric fan. This application also relates to a corresponding household appliance. Background Technology

[0002] Electric fans, as a common air circulation device, are widely used in various household appliances. Especially when electric fans are used in kitchen cooking equipment, such as ovens or steam ovens to achieve even heating or rapid heat dissipation, they are exposed to high temperature and high humidity environments for extended periods.

[0003] An electric fan motor consists of a stator and a rotor that work together. A certain gap is required between the stator and rotor to allow the rotor to rotate relative to the stator. However, when an electric fan operates in a high-temperature and high-humidity environment, moisture or dust can easily enter the motor through this gap. Over time, this can cause corrosion of the stator's silicon steel sheets and short circuits on the printed circuit board, ultimately severely affecting the electric fan's performance and lifespan. Summary of the Invention

[0004] Therefore, one object of this application is to provide an improved electric fan that can effectively improve waterproof and dustproof performance without significantly increasing manufacturing and assembly precision requirements, thereby cost-effectively extending the service life of the electric fan. Another object of this application is to provide a corresponding household appliance.

[0005] According to a first aspect of this application, an electric fan is provided, wherein the electric fan comprises at least: - A fixing assembly having a base, a stator disposed on the base, and a printed circuit board disposed between the base and the stator, wherein the base has a first end face with a flat configuration; - A rotating assembly having a shaft rotatably supported on the base and a rotor torsionally connected to the shaft and cooperating with the stator, wherein the rotor has a second end face with a flat construction, and the first end face and the second end face are axially opposed to each other. The base has two first annular walls extending from the first end face toward the second end face, and the rotor has a second annular wall extending from the second end face toward the first end face. The first and second annular walls are arranged alternately and spaced apart in the radial direction and partially overlap each other in the axial direction, such that a labyrinth structure with a meandering flow path is formed by the first and second annular walls. The labyrinth structure encloses an installation space in which the stator and the printed circuit board are arranged.

[0006] Compared to existing technologies, in the electric fan according to this application, the base of the stationary component has a flat first end face, while the rotor of the rotating component has a flat second end face. The base has two first annular walls extending from the first end face toward the second end face, and the rotor has a second annular wall extending from the second end face toward the first end face. The first and second annular walls are arranged alternately and spaced apart in the radial direction and partially overlap each other in the axial direction, thereby forming a labyrinth structure with a meandering flow path. The stator and printed circuit board of the stationary component are arranged in the mounting space enclosed by the labyrinth structure. The labyrinth structure significantly extends the path for moisture or dust to enter the mounting space and forms a rotating portion, effectively improving waterproof and dustproof performance. Furthermore, since both the first and second end faces are flat, greater adjustment space is provided for the design and assembly of the first and second annular walls without reducing the gap between the base and the rotor, which advantageously reduces the manufacturing and assembly precision requirements of the electric fan.

[0007] According to an exemplary embodiment of this application, a receiving space is formed between adjacent first annular walls and / or adjacent to the second annular wall, the receiving space being configured to receive humid and hot gases or condensate. The receiving space further enhances the waterproof and dustproof performance of the labyrinth structure.

[0008] According to an exemplary embodiment of this application, an adsorbent material or filter element is provided in the receiving space, which can minimize the entry of moisture or dust into the installation space; and / or, the axial direction is parallel to the direction of gravity, such that the first end face and the second end face are oriented perpendicular to the direction of gravity, wherein the lower end face of the first end face and the second end face is provided with a drain hole in the region of the receiving space, the drain hole being able to drain accumulated liquid water.

[0009] According to an exemplary embodiment of this application, viewed along the radial direction, the axial extension dimensions of the first annular wall and the second annular wall gradually increase towards the mounting space, such that the annular wall closer to the mounting space is longer than the annular wall farther from the mounting space; and / or, the overlap dimension of the first annular wall and the second annular wall in the axial direction is greater than or equal to half of the axial extension dimension of the first annular wall and / or the second annular wall; and / or, at least one of the first annular walls has a narrowed portion and / or a chamfered portion and / or a rounded portion at its free end facing the second end face. This ensures the length of the flow path in the labyrinth structure, thereby meeting the requirements for waterproofing and dustproofing.

[0010] According to an exemplary embodiment of this application, the rotor has a magnetic yoke ring, magnetic strips abutting the outer circumferential surface of the magnetic yoke ring, a rotor support for supporting the magnetic yoke ring, and an impeller, wherein the rotor support and the impeller are integrally constructed. This achieves good dynamic balance performance and improves structural strength.

[0011] According to an exemplary embodiment of this application, the rotor further has a third annular wall extending from the second end face toward the first end face. The third annular wall is located radially inside the second annular wall and is configured to support the magnetic strip. Here, the third annular wall can serve as a support structure to fix the magnetic strip, and can also act as part of a labyrinth structure in conjunction with the first and second annular walls to further improve waterproof and dustproof performance.

[0012] According to an exemplary embodiment of this application, the base includes a first base portion located radially inward and a second base portion located radially outward and fixedly connected to the first base portion. A first annular wall is disposed on the first base portion, wherein a stator support for supporting the stator is also disposed on the first base portion, the stator support being arranged radially inward of the first annular wall. This allows for a modular design of the base, facilitating assembly and maintenance. Furthermore, in the region corresponding to the first base portion, the rotating component has a smaller vibration amplitude relative to the stationary component, resulting in good stability of the electric fan in this region. Consequently, the first annular wall on the first base portion and the corresponding second annular wall have lower assembly precision requirements.

[0013] According to an exemplary embodiment of this application, the first base portion is constructed of plastic, and the second base portion is constructed of metal; and / or, the first base portion and the second base portion interlock with each other in a form-locking manner. This allows for flexible adjustment of the performance of different parts of the base and enables a simple and cost-effective assembly process.

[0014] According to an exemplary embodiment of this application, a sealing element is provided between the base and the printed circuit board. The sealing element can minimize the contact of moisture with the printed circuit board, thereby preventing short circuits or failure of the printed circuit board.

[0015] According to an exemplary embodiment of this application, the electric fan is configured as a centrifugal fan or an axial fan.

[0016] According to a second aspect of this application, a household appliance is provided, wherein the household appliance includes an electric fan according to this application. Attached Figure Description

[0017] The principles, features, and advantages of this application will be better understood below with reference to the accompanying drawings. The drawings include: Figure 1 A front view of an electric fan according to an exemplary embodiment of this application is shown; Figure 2 It shows Figure 1 A sectional view along section line SS; Figure 3 It shows Figure 2 A partial view; Figure 4a and Figure 4b A perspective view of the fixed assembly and the rotating assembly of an electric fan according to an exemplary embodiment of this application is shown.

[0018] Figure label: Electric fan 1; Fixing assembly 10; base 11; stator 12; printed circuit board 13; sealing element 14; bearing 15; axial positioning element 16; first end face 111; first base portion 112; second base portion 113; stator bracket 114; Rotating assembly 20; rotating shaft 21; rotor 22; second end face 221; magnetic yoke ring 222; magnetic strip 223; rotor support 224; impeller 225; First end face W1; Second end face W2; Third end face W3; Maze structure M; Installation space B; Receiving space C; Axial direction A; Radial direction R; Gravity direction G. Detailed Implementation

[0019] To make the technical problems to be solved, the technical solutions, and the beneficial technical effects of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and several exemplary embodiments. It should be understood that the specific embodiments described herein are only for explaining this application and are not intended to limit the scope of protection of this application. Here, for the sake of brevity, elements with the same reference numerals are indicated only once in the drawings when necessary.

[0020] It should be understood that the terms "first," "second," etc., used herein are for descriptive purposes only and should not be construed as indicating or implying relative importance, nor should they be construed as implicitly specifying the number of technical features indicated. Features specified as "first" or "second" may expressly or implicitly indicate that at least one of those features is included.

[0021] In the description of this embodiment, terms such as "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer" are used to indicate orientation or positional relationships in conjunction with the accompanying drawings to illustrate the positional relationships of the constituent elements. This is solely for the convenience of describing this specification and to simplify the description, and is not intended to indicate or imply that the device or element referred to has a specific orientation, or is constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this disclosure. The positional relationships of the constituent elements may be appropriately changed depending on the direction in which each constituent element is described. Therefore, the description is not limited to the terms used in the specification and may be appropriately replaced as needed.

[0022] Figure 1 A front view of an electric fan 1 according to an exemplary embodiment of this application is shown. Figure 2 It shows Figure 1 A sectional view along section line SS. Figure 3 It shows Figure 2 A partial view. Here, the electric fan 1 is specifically constructed for use in household appliances, such as ovens or steam ovens. Furthermore, the electric fan 1 is constructed, for example, as a centrifugal fan. It is also conceivable that the electric fan 1 is constructed as an axial fan or another fan type that is deemed meaningful by those skilled in the art.

[0023] like Figure 1 and Figure 2 As shown, the electric fan 1 includes a fixing assembly 10, which has a base 11, a stator 12 arranged on the base 11, and a printed circuit board 13 arranged between the base 11 and the stator 12. The stator 12 includes a plurality of stacked silicon steel sheets and stator windings embedded in the slots of the silicon steel sheets. Alternating current is supplied to the stator windings of the stator 12 through the printed circuit board 13, thereby causing the stator 12 to generate a rotating magnetic field.

[0024] like Figure 1 and Figure 2 As shown, the electric fan 1 includes a rotating assembly 20, which is rotatable relative to the fixed assembly 10. The rotating assembly 20 has a shaft 21 rotatably supported on a base 11 and a rotor 22 torsionally connected to the shaft 21 and cooperating with a stator 12. The rotor 22 rotates under the influence of a magnetic field generated by the stator 12. A bearing 15 is provided between the shaft 21 and the base 11, allowing the shaft 21 to be smoothly rotatably supported on the base 11. In particular, an axial positioning element 16 is provided for the shaft 21 to control and adjust the axial clearance between the fixed assembly 10 and the rotating assembly 20. The axial positioning element 16 may include, for example, a spring, a washer, or a retaining ring.

[0025] like Figure 2 and Figure 3As shown, the base 11 of the fixed assembly 10 has a flat first end face 111, while the rotor 22 of the rotating assembly 20 has a flat second end face 221. The first end face 111 and the second end face 221 are opposite each other in the axial direction A. The base 11 has two first annular walls W1 extending from the first end face 111 toward the second end face 221, and the rotor 22 has a second annular wall W2 extending from the second end face 221 toward the first end face 111. The first annular walls W1 and the second annular walls W2 are arranged alternately and spaced apart in the radial direction R, such that the second annular wall W2 is inserted between the two first annular walls W1 and partially overlaps each other in the axial direction A. Thus, a labyrinth structure M with a meandering flow path is formed by the first annular walls W1 and the second annular walls W2. This flow path has multiple turning parts. The labyrinth structure M encloses an installation space B in which the stator 12 and the printed circuit board 13 are arranged. In this configuration, hot, humid air or dust entering the labyrinth structure M from the external environment will encounter and condense and accumulate on the respective annular walls. Thus, only a very small amount of moisture or dust can reach the installation space B through the labyrinth structure M, significantly improving the dustproof and waterproof performance of the electric fan 1. Furthermore, the flat construction of the first end face 111 and the second end face 221 allows for flexible adjustment of the axial extension dimensions of the first annular wall W1 and the second annular wall W2 to achieve an optimized sealing effect of the labyrinth structure M. This provides greater adjustment space for the design and assembly of the first annular wall W1 and the second annular wall W2 without reducing the gap between the base 11 and the rotor 22, thereby cost-effectively reducing the manufacturing and assembly precision requirements of the electric fan 1.

[0026] For example, such as Figure 3 As shown, a receiving space C is formed between adjacent first annular walls W1. This receiving space C is configured to receive humid air or condensate, allowing the humid air or condensate to remain within the receiving space C, thereby preventing water vapor or liquid water from further flowing into the installation space B. Furthermore, a receiving space C can also be formed in the area adjacent to the second annular wall W2, particularly around the connection between the second annular wall W2 and the second end face 221. In particular, an adsorbent or filter material, such as activated carbon or a filter screen, is provided in the receiving space C. This adsorbent or filter material can capture water vapor or dust as much as possible, thereby significantly improving the sealing effect of the labyrinth structure M.

[0027] For example, such as Figure 3As shown, the first end face 111 of the base 11 and the second end face 221 of the rotor 22 are both perpendicular to the axial direction A, which is parallel to the gravitational direction G. The rotating assembly 20 is located below the fixed assembly 10 along the gravitational direction G. Alternatively, the rotating assembly 20 may be located above the fixed assembly 10 along the gravitational direction G. Specifically, the lower end face of the first end face 111 and the second end face 221... Figure 3 The second end face 221 has a drainage hole in the area of ​​the receiving space C. The liquid water that accumulates in the receiving space C under the action of gravity can be drained through the drainage hole to keep the labyrinth structure M as dry as possible.

[0028] For example, such as Figure 2 and Figure 3 As shown, viewed radially along the R direction, the axial extension dimensions of the first annular wall W1 and the second annular wall W2 gradually increase towards the installation space B, such that the annular wall closer to the installation space B is longer than the annular wall farther from the installation space B. In this case, the overlap dimension of the first annular wall W1 and the second annular wall W2 on the radially innermost side is greater than the overlap dimension of the first annular wall W1 and the second annular wall W2 on the radially outermost side. This makes the flow path on the radially inner side of the labyrinth structure M correspondingly longer than the flow path on the radially outer side. This makes it easier for moisture to condense at the first annular wall W1 on the radially inner side and further increases the difficulty for moisture to pass through the labyrinth structure M.

[0029] For example, such as Figure 2 and Figure 3 As shown, the overlap dimension of the first annular wall W1 and the second annular wall W2 in the axial direction A is greater than or equal to half of the axial extension dimension of the first annular wall W1 and / or the second annular wall W2. This ensures that the length of the flow path of the labyrinth structure M is sufficient to cause the moisture-heavy water to condense, thereby meeting the waterproof requirements.

[0030] For example, such as Figure 3 As shown, at least one of the first annular walls W1 has a narrowed portion and / or a chamfered portion and / or a rounded portion on its free end facing the second end face 221. This free end configuration provides assembly guidance and optimizes airflow to reduce flow noise.

[0031] Figure 4a and Figure 4b A perspective view of the fixed assembly 10 and the rotating assembly 20 of an electric fan 1 according to an exemplary embodiment of this application is shown.

[0032] For example, such as Figure 2 and Figure 3As shown, the rotor 22 has a magnetic yoke ring 222 and magnetic strips 223 abutting the outer circumferential surface of the magnetic yoke ring 222. The magnetic strips are made of permanent magnet material and provide a constant magnetic field. This magnetic field interacts with the rotating magnetic field generated by the stator 12, thereby causing the rotor 22 to rotate. The magnetic yoke ring 222 is formed by stacking high-permeability silicon steel sheets and enhances the magnetic field generated by the magnetic strips 223. The magnetic strips 223 are fixed to the magnetic yoke ring 222, for example, by interference fit or bonding. Furthermore, the rotor 22 also has a rotor support 224 for supporting the magnetic yoke ring 222. The magnetic yoke ring 222 is fixed to the rotor support 224, for example, by interference fit or bonding, thereby driving the rotor support 224 to rotate. Additionally, the rotor 22 has an impeller 225, which is fixedly connected to the rotor support 224, so that the rotor support 224 further drives the impeller 225 to rotate, thereby generating airflow. In particular, the rotor support 224 and the impeller 225 are integrally constructed, and are made of engineering plastics or alloys, such as... Figure 4b As shown. This allows for good dynamic balance performance of the rotating component 20 and improves its structural strength.

[0033] For example, such as Figure 2 and Figure 3 As shown, the rotor 22 also has a third annular wall W3 extending from the second end face 221 toward the first end face 111. The third annular wall W3 is located radially inside the second annular wall W2 and is configured to support the magnetic strip 223. Here, the magnetic strip 223 can be form-fitted into or bonded to the third annular wall W3, thereby improving the assembly stability of the yoke ring 222 and the magnetic strip 223. Furthermore, the third annular wall W3 can also function as part of the labyrinth structure M, working in conjunction with the first annular wall W1 and the second annular wall W2. This further extends the flow path of the labyrinth structure M, making it more difficult for moisture to reach the installation space B, thereby further improving the waterproof and dustproof performance of the electric fan 1.

[0034] For example, such as Figures 2 to 4aAs shown, the base 11 is constructed in two parts and includes a first base portion 112 located radially inward and a second base portion 113 located radially outward and fixedly connected to the first base portion 112. A first annular wall W1 is disposed on the first base portion 112, and a stator support 114 for supporting the stator 12 is also disposed on the first base portion 112. The stator support 114 is arranged radially inward of the first annular wall W1, such that the stator 12 supported by the stator support 114 can be arranged in the installation space B enclosed by the labyrinth structure M including the first annular wall W1. The second base portion 112 corresponds to the impeller 225 of the rotor 22 in the axial direction A. This allows for a modular design of the base 11, where the first base portion 112 fulfills the functions of supporting the stator 12 and sealing, while the second base portion 113 fulfills the functions of fixed connection with external systems and forming an aerodynamic interface with the impeller 225. In this configuration, the base 11 can be designed more specifically and is easier to maintain and replace. Furthermore, corresponding to the second base portion 113, the impeller 225 is located radially outside the rotor 22 and far from the shaft 11, thus having relatively low structural rigidity. This results in the impeller 225 having a larger vibration amplitude relative to the second base portion 113, while the rotor support 224 has a relatively smaller vibration amplitude relative to the first base portion 112. In this case, the labyrinth structure M formed by the first annular wall W1 and the corresponding second annular wall W2 arranged on the first base portion 112 is subjected to lower vibration influence, resulting in lower assembly precision requirements for the first annular wall W1 and the second annular wall W2. This is beneficial for the cost-effective design and assembly of the labyrinth structure M. In particular, the first base portion 112 is constructed of plastic, while the second base portion 113 is constructed of metal. Here, the first base portion 112 and the second base portion 113 can be interlocked with each other in a form-locking manner, which enables reliable fixation and easy assembly of the base 11.

[0035] For example, such as Figure 2 and Figure 3 As shown, a sealing element 14 is additionally provided between the base 11 and the printed circuit board 13. The sealing element 14 can further improve the sealing performance, thereby preventing moisture from contacting the printed circuit board 13 to the greatest extent and ensuring the operational stability of the electric fan 1.

[0036] Although specific embodiments have been described above, these embodiments are not intended to limit the scope of this application, even when only a single embodiment is described with respect to a particular feature. The feature examples provided in this application are intended for illustrative purposes and not for limitation, unless otherwise stated. In practice, multiple features may be combined with each other as needed and where technically feasible. Various substitutions, modifications, and alterations are also conceived without departing from the spirit and scope of this application.

Claims

1. An electric fan (1), characterized in that, The electric fan (1) includes at least: - A fixing assembly (10) having a base (11), a stator (12) disposed on the base (11) and a printed circuit board (13) disposed between the base (11) and the stator (12), wherein the base (11) has a first end face (111) with a flat structure. - A rotating assembly (20) having a shaft (21) rotatably supported on the base (11) and a rotor (22) torsionally connected to the shaft (21) and cooperating with the stator (12), wherein the rotor (22) has a second end face (221) with a flat construction, and the first end face (111) and the second end face (221) are opposite each other in the axial direction (A). The base (11) has two first annular walls (W1) extending from the first end face (111) toward the second end face (221), and the rotor (22) has a second annular wall (W2) extending from the second end face (221) toward the first end face (111). The first annular walls (W1) and the second annular walls (W2) are arranged alternately and spaced apart in the radial direction (R) and partially overlap each other in the axial direction (A), such that a labyrinth structure (M) with a meandering flow path is formed by the first annular walls (W1) and the second annular walls (W2). The labyrinth structure (M) encloses an installation space (B) in which the stator (12) and the printed circuit board (13) are arranged.

2. The electric fan (1) according to claim 1, characterized in that, A receiving space (C) is formed between adjacent first annular walls (W1) and / or adjacent to the second annular wall (W2), the receiving space (C) being configured to receive hot and humid gas or condensate.

3. The electric fan (1) according to claim 2, characterized in that, An adsorbent material or a filter element is provided in the receiving space (C); and / or The axial direction (A) is parallel to the gravity direction (G), such that the first end face (111) and the second end face (221) are oriented perpendicular to the gravity direction (G), wherein the lower end face of the first end face (111) and the second end face (221) is provided with a drainage hole in the region of the receiving space (C).

4. The electric fan (1) according to any one of claims 1 to 3, characterized in that, Viewed along the radial direction (R), the axial extension dimensions of the first annular wall (W1) and the second annular wall (W2) are arranged to gradually increase toward the mounting space (B), such that the annular wall closer to the mounting space (B) is longer than the annular wall farther from the mounting space (B); and / or The overlap dimension of the first annular wall (W1) and the second annular wall (W2) in the axial direction (A) is greater than or equal to half the axial extension dimension of the first annular wall (W1) and / or the second annular wall (W2); and / or At least one of the first annular walls (W1) has a narrowed portion and / or a beveled portion and / or a rounded portion on its free end facing the second end face (221).

5. The electric fan (1) according to any one of claims 1 to 3, characterized in that, The rotor (22) has a magnetic yoke ring (222), a magnetic strip (223) abutting the outer circumferential surface of the magnetic yoke ring (222), a rotor support (224) for supporting the magnetic yoke ring (222), and an impeller (225), wherein the rotor support (224) and the impeller (225) are integrally constructed.

6. The electric fan (1) according to claim 5, characterized in that, The rotor (22) also has a third annular wall (W3) extending from the second end face (221) toward the first end face (111), the third annular wall (W3) being located radially inside the second annular wall (W2) and configured to support the magnetic strip (223).

7. The electric fan (1) according to any one of claims 1 to 3, characterized in that, The base (11) includes a first base portion (112) located radially inside and a second base portion (113) located radially outside and fixedly connected to the first base portion (112). The first annular wall (W1) is disposed on the first base portion (112). A stator support (114) for supporting the stator (12) is also disposed on the first base portion (112). The stator support (114) is arranged radially inside the first annular wall (W1).

8. The electric fan (1) according to claim 7, characterized in that, The first base portion (112) is constructed of plastic, and the second base portion (113) is constructed of metal; and / or The first base portion (112) and the second base portion (113) are interlocked in a shape-locking manner.

9. The electric fan (1) according to any one of claims 1 to 3, characterized in that, A sealing element (14) is provided between the base (11) and the printed circuit board (13); and / or The electric fan (1) is constructed as a centrifugal fan or an axial flow fan.

10. A household appliance, characterized in that, The household appliance includes an electric fan (1) according to any one of the preceding claims.

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