Fan and water heater

Abstract

The utility model discloses a draught fan and a water heater, and relates to the technical field of water heaters, the draught fan comprises a volute assembly and an impeller, the impeller comprises at least two layers of blade sets which are arranged in the axial direction, each blade set comprises a plurality of blades which are arranged in the circumferential direction of the impeller at intervals, and the blades of every two adjacent layers of blade sets are arranged in a staggered mode. Volute tongue gaps between the volute tongue and the impeller are arranged in the axial direction of the volute in a non-equidistant mode. According to the technical scheme, the blades of the two adjacent layers of blade sets are arranged in the staggered mode, the vortex structure of airflow can be effectively broken and dispersed, the airflow path can be changed, the airflow can pass through the impeller more stably, vortex forming and strength are reduced, and therefore vortex noise is lowered. In addition, according to the technical scheme, the volute tongue gaps in the axial direction are set to be non-equidistant, so that formation of vortexes and turbulent flows is reduced by changing the airflow direction, the airflow is more stable, and noise is reduced accordingly.

Description

Technical Field

[0001] The utility model relates to the technical field of water heaters, and particularly relates to a fan and a water heater. Background Art

[0002] In modern industrial and architectural environments, fans are widely used in fields such as ventilation, refrigeration, and air purification. However, the noise generated during fan operation is relatively high. High noise not only affects the comfort of the working and living environments but may also have an adverse impact on human health. Summary of the Utility Model

[0003] The main purpose of the utility model is to propose a fan and a water heater, aiming to reduce the noise of the fan.

[0004] To achieve the above object, the fan proposed by the utility model includes:

[0005] A volute component, having a fan cavity, an air inlet and an air outlet communicated with the fan cavity, and the volute includes a volute tongue corresponding to the air outlet;

[0006] An impeller, which is arranged in the fan cavity. The impeller includes at least two layers of blade groups arranged axially. Each blade group includes a plurality of blades arranged at intervals in the circumferential direction of the impeller. The blades of adjacent two layers of blade groups are arranged in a staggered manner, and the volute tongue gap between the volute tongue and the impeller is arranged in a non-uniform distance in the axial direction of the volute component.

[0007] In one embodiment, in the axial direction of the volute component, the volute tongue gap gradually increases or gradually decreases from one end of the volute component to the other end.

[0008] In one embodiment, the volute component has two ends arranged oppositely along its axial direction, and the volute tongue gap gradually decreases from the two ends of the volute component to the middle.

[0009] In one embodiment, in the axial direction of the volute component, the volute tongue gap corresponding to the middle position of the volute tongue is the smallest.

[0010] In one embodiment, the outlet height of the impeller is the sum of the vertical distances from the outlet edge of any blade in each blade group to the central axis of the impeller. The ratio between the outlet height of the impeller and the outer diameter of the impeller is the width-diameter ratio, and the width-diameter ratio is not less than 0.4 and not greater than 0.6.

[0011] In one embodiment, the ratio between the outlet height of the volute component and the outer diameter of the impeller is not less than 0.6 and not greater than 0.7.

[0012] In one embodiment, the clearance between the inner wall on the air inlet side of the volute assembly and the impeller is not less than 3 mm and not more than 6 mm.

[0013] In one embodiment, the volute assembly further includes a volute main body and a cover plate. The volute main body has an installation opening, and the cover plate seals the installation opening.

[0014] The cover plate includes a plate body and a convex portion provided on the plate body. The plate body and the volute main body enclose the fan cavity. The convex portion is arranged in a ring shape, the convex portion covers the stator assembly of the motor, the convex portion is integrally formed with the stator assembly, and the convex portion encloses a motor cavity for installing the rotor assembly of the motor.

[0015] In one embodiment, the volute further includes an insert, the insert is integrally formed with the cover plate, and the insert is connected to the volute main body.

[0016] The present utility model also provides a water heater, which includes a blower as described in any of the foregoing embodiments.

[0017] The technical solution of the present utility model can effectively break and disperse the vortex structure of the air flow and change the air flow path by arranging the blades of adjacent two-layer blade groups in a staggered manner, so that the air flow passes through the impeller more smoothly, reduces the formation and intensity of the vortex, and thus reduces the vortex noise. In addition, the technical solution of the present utility model also sets the volute tongue clearance in the axial direction to be non-uniform, so as to reduce the formation of vortex and turbulence by changing the air flow direction, make the air flow more stable, and thus reduce the noise. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0019] Figure 1 It is a schematic structural diagram of an embodiment of a blower assembly provided by the present utility model;

[0020] Figure 2 It is Figure 1 a cross-sectional view in one direction of

[0021] Figure 3 It is Figure 2 an enlarged view of part A in

[0022] Figure 4 It is Figure 1Exploded view;

[0023] Figure 5 is Figure 4 Schematic structural diagram of an embodiment of the insert in

[0024] Figure 6 is Figure 4 Schematic structural diagram of an embodiment of the end cover in

[0025] Figure 7 is Figure 4 Schematic structural diagram of an embodiment of the volute body in

[0026] Figure 8 is Figure 4 Cross-sectional view of the end cover in one direction;

[0027] Figure 9 Schematic structural diagram of another embodiment of the fan assembly provided by the present utility model;

[0028] Figure 10 is Figure 9 Side view of

[0029] Figure 11 is Figure 10 Cross-sectional view A-A in

[0030] Figure 12 is Figure 11 Schematic structural diagram of another embodiment of the cross-sectional view shown;

[0031] Figure 13 is Figure 11 Schematic structural diagram of yet another embodiment of the cross-sectional view shown;

[0032] Figure 14 Velocity vector distribution diagrams of different cross-sections of the volute tongue with the volute tongue gap arranged at equal intervals in the axial direction of the volute. Among them, (a) is at the center plane of the volute, (b) is at the cross-section near the bottom end, with a distance of 0.02 m, and (c) is at the cross-section near the air inlet of the volute, with a distance of 0.02 m;

[0033] Figure 15 Velocity vector distribution diagrams of different cross-sections of the volute tongue with the volute tongue gap arranged at non-equal intervals in the axial direction of the volute. Among them, (a) is at the center plane of the volute, (b) is at the cross-section near the bottom end, with a distance of 0.02 m, and (c) is at the cross-section near the air inlet of the volute, with a distance of 0.02 m;

[0034] Figure 16 Velocity vector distribution diagrams of different cross-sections of the volute tongue with the volute tongue gap arranged at non-equal intervals in the axial direction of the volute in another embodiment. Among them, (a) is at the center plane of the volute, (b) is at the cross-section near the bottom end, with a distance of 0.02 m, and (c) is at the cross-section near the air inlet of the volute, with a distance of 0.02 m;

[0035] Figure 17 Pressure distribution diagram of the center section of the impeller and volute under the condition that the outlet static pressure P is 300 Pa, where (a) the width-diameter ratio is 0.519, (b) the width-diameter ratio is 0.506, and (c) the width-diameter ratio is 0.439;

[0036] Figure 18 Velocity vector diagram of the impeller near the bottom surface of the volute (0.02 m away from the center plane of the impeller) under the condition that the outlet static pressure is 0 Pa, where (a) the width-diameter ratio is 0.519, (b) the width-diameter ratio is 0.506, and (c) the width-diameter ratio is 0.439;

[0037] Figure 19 Pressure distribution diagram of the impeller near the bottom surface of the volute (0.02 m away from the center plane of the impeller) under the condition that the outlet static pressure P is 0 Pa, where (a) the width-diameter ratio is 0.519, (b) the width-diameter ratio is 0.506, and (c) the width-diameter ratio is 0.439;

[0038] Figure 20 Meridional plane velocity vector distribution diagram of the volute air inlet under the condition that the outlet static pressure P is 0 Pa, where (a) the ratio of the volute outlet height to the impeller outer diameter is 0.61, (b) the ratio of the volute outlet height to the impeller outer diameter is 0.65, and (c) the ratio of the volute outlet height to the impeller outer diameter is 0.68;

[0039] Figure 21 Characteristic curve diagrams of the fans and the prototype in three embodiments where the ratio of the outlet height of the three volutes to the outer diameter of the impeller is between 0.6 and 0.7;

[0040] Figure 22 Characteristic curve diagrams of the fans and the prototype in three embodiments where the contour parameters of the impeller are between 0.4 and 0.6;

[0041] Figure 23 Characteristic curve diagrams of the fans and the prototype in three embodiments where the ratio of the volute outlet height to the impeller outer diameter is between 0.6 and 0.7;

[0042] Figure 24 Inlet noise value of a fan in an embodiment of the present utility model;

[0043] Figure 25 Outlet noise value of a fan in an embodiment of the present utility model.

[0044] Explanation of the reference numerals in the drawings:

[0045] 1. Fan assembly; 10. Fan; 100. Volute assembly; 101. Air inlet; 102. Air outlet; 103. Installation port; 104. Opening; 110. Volute main body; 111. Welding part; 112. Flange; 120. Cover plate; 121. Plate body; 122. Protrusion; 122a. First protruding sub - part; 122b. Second protruding sub - part; 123. Fitting part; 124. Positioning part; 130. Insert; 131. Welding groove; 132. Fastening part; 140. Volute tongue; 141. Volute tongue clearance; 200. Impeller; 210. Hub; 220. Blades; 201. Accommodation groove; 230. Disk; 300. Connection assembly; 310. Insert; 311. Insert body; 312. Embedding part; 313. Reinforcement part; 320. Connector; 321. Connection frame; 322. Connection part; 322a. Connection sub - part; 322b. Folded part; 323. Clamping part; 324. Flange; 330. Clamping piece; 20. Driving motor; 21. Stator assembly; 22. Rotor assembly; 22a. Rotating shaft; 22b. Rotor core; 22c. First bearing; 22d. Second bearing; 23. End cover; 23a. End part; 23b. Limiting part; 23c. Abutting part.

[0046] The realization of the purpose, functional features and advantages of the present utility model will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0047] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0048] It should be noted that if there are directional indications (such as up, down, left, right, front, back,...) involved in the embodiments of the present utility model, the directional indications are only used to explain the relative position relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0049] In addition, if the embodiments of the present utility model involve descriptions such as "first", "second", etc., the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel scenarios. Taking "A and / or B" as an example, it includes Scenario A, or Scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0050] The present utility model provides a fan, aiming to reduce the noise of the fan. For the convenience of understanding and description, in the attached Figures 1 to 25 drawings of the present utility model, the solid arrow indicates space, slot or hole. The following are several industry-specific terms involved in this case:

[0051] Volute tongue clearance: the distance between the volute tongue of a centrifugal fan and the outer edge of the impeller; Outlet height of the impeller: the vertical distance from the outlet edge of the blade to the central axis of the impeller; For a multi-layer impeller, the outlet height of the impeller is the sum of the vertical distances from the outlet edge of any blade in each blade group of each layer to the central axis of the impeller; Outlet height of the volute: the cross-sectional height at the volute air outlet, that is, the height in the axial direction of the volute air outlet.

[0052] Please refer to Figure 4 and 11 , in an embodiment of the present utility model, the fan 10 includes a volute assembly 100 and an impeller 200. The volute assembly 100 has a fan cavity, and an air inlet 101 and an air outlet 102 communicated with the fan cavity. The volute includes a volute tongue 140 corresponding to the air outlet 102; The impeller 200 is arranged in the fan cavity. The impeller 200 includes at least two layers of blade groups arranged axially. Each layer of blade group includes a plurality of blades 220 arranged at intervals in the circumferential direction of the impeller 200. The blades 220 of adjacent two layers of blade groups are arranged in a staggered manner. The volute tongue clearance 141 between the volute tongue 140 and the impeller 200 is arranged non-equidistantly in the axial direction of the volute assembly 100.

[0053] The structure of the fan 10 will be specifically described below.

[0054] Regarding the fan 10, the fan 10 is usually a centrifugal fan 10, and the fan 10 mainly includes a volute assembly 100 and an impeller 200, and the impeller 200 is arranged in the volute assembly 100. Generally speaking, the volute assembly 100 includes a volute body 110 and a cover plate 120. The volute body 110 usually includes a bottom plate and a surrounding plate. The bottom plate and the surrounding plate can be integrally formed or separately set. Preferably, the bottom plate and the surrounding plate are integrally formed, and the shape of the volute assembly 100 is determined by the profile of the surrounding plate. The volute body 110 is constructed with an air inlet 101, an air outlet 102 and an installation port 103. The cover plate 120 is used to cover the installation port 103. The volute body 110 and the cover plate 120 enclose a fan cavity, and the air inlet 101 and the air outlet 102 are both connected to the fan cavity. The main function of the air inlet 101 is to guide the fluid (gas or liquid) into the impeller 200. It is usually designed to be smooth in shape to reduce flow resistance and pressure loss; the main function of the air outlet 102 is to guide the fluid to leave the volute assembly 100, usually after the fluid passes through the impeller 200 and converts kinetic energy into pressure energy in the volute assembly 100; the main function of the installation port 103 is to install the impeller 200 into the fan cavity. Preferably, in order to facilitate the installation of the impeller 200 and the volute body 110, the above-mentioned installation port 103 is usually open. Of course, in other embodiments, the installation port 103 can be non-open.

[0055] Regarding the impeller 200, the main structure of the impeller 200 generally includes a blade disk, a hub 210 and blades 220, and the hub 210 is connected to the rotor assembly 22 in a transmission manner. The blade disk is a component that connects the blade 220 and the shaft, and is usually made of stainless steel or aluminum alloy. Its function is to fix the blade 220 and the hub 210 so that they can rotate together; the blade 220 is the main structural component of the impeller 200, which is responsible for converting energy into fluid kinetic energy or static energy. According to the different structures and fluid characteristics of the blade 220, it can be divided into straight blades 220, twisted blades 220, and blades 220 limited to static pressure type, etc.; the hub 210 is the central part of the impeller 200, carrying the blades 220 and the blade disk, and is responsible for transmitting the rotational force to the shaft in order to improve the strength and rigidity of the hub 210. In this embodiment, the impeller 200 is a multi-layer impeller 200, including but not limited to double layers, three layers or four layers and more than 4 layers. Each layer of the impeller 200 includes a group of blades 220.

[0056] The following takes the double-layer impeller 200 as an example for introduction. The impeller 200 includes a first disk 230, a second disk 230, and a third disk 230 that are coaxially arranged and sequentially arranged in a certain direction. Both ends of a blade group are respectively connected to the first disk 230 and the second disk 230, and a blade assembly is respectively connected to the second disk 230 and the third disk 230. In the two-layer blade group, in the staggered arrangement of the blades 220, it mainly includes axial stagger, radial stagger, angular stagger, or compound stagger. Axial stagger refers to that two groups of blades 220 are staggered by a certain distance in the axial direction (along the rotation axis direction). Radial stagger refers to that two groups of blades 220 are staggered by a certain distance in the radial direction (perpendicular to the rotation axis direction). Angular stagger refers to that two groups of blades 220 are staggered in terms of angle, that is, the installation angles of the two groups of blades are different. Compound stagger refers to combining the above multiple staggering methods to stagger two groups of blades 220 axially, radially, and angularly.

[0057] Regarding the volute tongue 140 and the volute tongue clearance 141, the volute tongue 140 is a part of the volute. It is located at the outlet of the volute and usually plays a role in guiding and accelerating the fluid. The volute tongue clearance 141 (also known as the volute tongue 140 spacing or the volute tongue clearance 141 distance) refers to the distance between the volute tongue 140 of the volute in the centrifugal fan 10 or the centrifugal pump and the outer edge of the impeller 200.

[0058] Regarding the volute tongue clearance 141 between the volute tongue 140 and the impeller 200, it is arranged non-equidistantly in the axial direction of the volute. For example, in the axial direction of the volute, the size change of the volute tongue clearance 141 shows an increasing trend, that is, including gradually increasing or stepwise increasing, etc. Or, in the axial direction of the volute, the size change of the volute tongue clearance 141 shows a decreasing trend, that is, including gradually decreasing or stepwise decreasing, etc. Exemplarily, in the axial direction of the volute assembly 100, the volute tongue clearance 141 gradually increases from one end of the volute assembly 100 to the other end, or gradually decreases. Or, the volute assembly 100 has two ends oppositely arranged along its axial direction, and the volute tongue clearance 141 gradually decreases from the two ends of the volute assembly 100 to the middle. Preferably, in the axial direction of the volute assembly 100, the volute tongue clearance 141 corresponding to the midpoint position of the volute tongue 140 is the smallest. Setting the minimum value of the volute tongue clearance 141 at the middle of the volute tongue 140 can help form a more uniform pressure distribution inside the volute, avoiding local high-pressure or low-pressure regions. Thereby reducing the asymmetric force acting on the impeller 200, and further extending the equipment life.

[0059] To verify the technical effects achieved by the fan 10 of this embodiment, under the same number of blades 220 and operating conditions, the fan 10 of the present invention and the conventional fan 10 were respectively tested. The following is the process of the experiment:

[0060] Among them, the treatment of the profile line of the volute tongue 140 often has a greater impact on the air volume and noise results of the fan 10. In this fan 10, the inner profile line at the volute tongue 140 adopts a treatment method of right-angled chamfered fillets with different diameters. The inner profile line at the volute tongue 140 can be an arc of a right-angled chamfered fillet, or multiple arcs of right-angled chamfered fillets. The radius of the designed fillet is defined as rwi (where i is a natural number), specifying the length of the chamfer radius. The position of the variable radius point is defined to form an inclined volute tongue 140. A plane parallel to the volute inlet surface plane is drawn through the variable radius point, and the radial distance between the parallel plane and the volute inlet surface is defined as Li (where i is a natural number). For each fillet segment, there are two parameters, rwi and Li, for constraint.

[0061] A 60W power is adopted, and three measurement schemes are set as follows:

[0062] Scheme 1: rw1 is 4mm and L1 is 0mm (that is, the fillet radius is the same and there is no variable radius point);

[0063] Scheme 2: rw1 is 8mm, L1 is 0mm, rw2 is 4mm, and L2 is 55mm (that is, the fillet radius of the volute tongue 140 at the position of the volute inlet surface 101 is 8mm, the radius of the volute tongue 140 at the bottom surface of the volute is 4mm, and the radius of the volute tongue 140 increases uniformly from the inlet surface to the bottom surface);

[0064] Scheme 3: rw1 is 4mm, L1 is 0mm, rw2 is 8mm, L2 is 38.6mm, rw3 is 4mm, and L3 is 55mm (that is, the fillet radii at the volute inlet surface 101 and the bottom surface of the volute are 4mm, the maximum radius is 8mm at the middle position, and the radius gradually decreases from the middle to both end faces);

[0065] The actual characteristic curve of the ventilator 10, the noise value at the air inlet 101, and the noise value at the air outlet 102 are measured respectively, and the experimental data are presented in the form of charts. The summary chart is as Figures 23 to 25 shown. It can be observed from Figures 23 to 25 the experimental data that the overall effect of the variable radius volute tongue 140 of the volute tongue 140 profile line is better than that of the volute tongue 140 with the same fillet at each segment. The volute tongue 140 of Scheme 3 has a significant advantage in the flow rate in the low-pressure area (471Pa).

[0066] To further verify this result, relevant simulation experiments are also carried out. For details, please refer to Figures 14 to 16 . Figure 14 It is a distribution diagram of the velocity vectors of different cross-sections of the volute tongue 140 in an embodiment where the volute tongue gap 141 is arranged at equal intervals in the axial direction of the volute casing in Scheme 1. Among them, (a) is at the center plane of the volute casing, (b) is at the cross-section close to the bottom end, and the distance is 0.02m, and (c) is at the cross-section close to the volute inlet 101, and the distance is 0.02m; Figure 15Velocity vector distribution diagrams of different cross-sections of the volute tongue 140 in an embodiment where the volute tongue gap 141 is arranged non-equidistantly in the axial direction of the volute for Solution 2. Among them, (a) is at the center plane of the volute, (b) is at a cross-section close to the bottom end, and the distance is 0.02 m, and (c) is at a cross-section close to the air inlet 101 of the volute, and the distance is 0.02 m. Figure 16 Velocity vector distribution diagrams of different cross-sections of the volute tongue 140 in another embodiment where the volute tongue gap 141 is arranged non-equidistantly in the axial direction of the volute for Solution 3. Among them, (a) is at the center plane of the volute, (b) is at a cross-section close to the bottom end, and the distance is 0.02 m, and (c) is at a cross-section close to the air inlet 101 of the volute, and the distance is 0.02 m.

[0067] In the axial direction of the volute, the volute tongue with a constant volute tongue gap 141 is a straight volute tongue 140, the volute tongue with a gradually increasing or gradually decreasing volute tongue gap 141 is a single-sided inclined volute tongue 140, and the volute tongue 140 has two ends arranged oppositely along its axial direction. The volute tongue 140 with a volute tongue gap 141 gradually decreasing from both ends of the volute tongue 140 to the middle is a double-sided inclined volute tongue 140. From the above experimental results, as Figure 14 shown, in the case of a straight volute tongue 140 under low pressure, there is a large proportion of air flow incident radially on the wall surface of the volute tongue 140 at the front cross-section (the cross-section close to the air inlet 101 of the volute, Figure c), the middle cross-section (at the center plane of the volute, Figure a), and the rear cross-section (the cross-section close to the bottom end, Figure b), resulting in a certain loss. As Figure 15 shown, the radially incident air flow on the circumferential wall surface of the volute tongue 140 is significantly reduced. For the single-sided inclined volute tongue 140, the diameter of the volute tongue 140 gradually increases from the rear side to the front side of the impeller 200. The larger the change range of the diameter of the volute tongue 140, the easier it is to form a local high-speed area in the gap between the volute and the impeller 200 below the volute tongue, resulting in partial static pressure loss. In contrast, Figure 16 shown, the double-sided inclined volute tongue 140 not only reduces the loss of high-speed air flow directly impacting the corner wall surface of the volute tongue, but also controls the maximum speed of the high-speed area formed by the increase in diameter on both sides, becoming the optimized design solution with the least loss.

[0068] The technical solution of the present utility model can effectively break and disperse the eddy current structure of the air flow and change the air flow path by arranging the blades 220 of adjacent two-layer blade groups in a staggered manner, so that the air flow passes through the impeller 200 more smoothly, reducing the formation and intensity of eddy currents, thereby reducing the eddy current noise. In addition, the technical solution of the present utility model also sets the volute tongue gap 141 in the axial direction to be non-equidistant, thereby reducing the formation of eddy currents and turbulence by changing the air flow direction, making the air flow more stable and reducing the noise accordingly.

[0069] In another embodiment, in order to improve the wind resistance of the impeller 200, the outlet height of the impeller 200 is the sum of the vertical distances from the outlet edge of any blade 220 in each layer of blade groups to the central axis of the impeller 200. The ratio between the outlet height of the impeller 200 and the outer diameter of the impeller 200 is the width-diameter ratio, and the width-diameter ratio is not less than 0.4 and not greater than 0.6.

[0070] To verify the technical effects achieved by the fan 10 of this embodiment, under the same number of blades 220 and operating conditions, the fan 10 of the present utility model and a conventional fan 10 were respectively tested. The following is the process of the experiment:

[0071] Since the outer diameter of the impeller 200 and the outlet height of the impeller 200 jointly determine the shape of the impeller 200, the outer diameter of the impeller 200 is set as D2, and the outlet height of the impeller 200 is set as b2. Define the dimensionless profile shape parameter:

[0072] Among them, taking a single-layer impeller 200 as an example, the outlet height of the impeller 200 is the vertical distance from the outlet edge of the blade 220 to the central axis of the impeller 200. If it is a double layer, the outlet height of the impeller 200 is the sum of the vertical distances from the outlet edge of any blade 220 in each layer of blade groups to the central axis of the impeller 200. Specifically, as Figure 11 shown, the outlet height b2 of the impeller 200 is the sum of the outlet height b21 of the first-layer blade group and the outlet height b22 of the second-layer blade group. For a volute with a determined line shape, with a power of 30W, three measurement schemes are set as follows:

[0073] Scheme 1: D2 is 82.5 mm and b2 is 42.8 mm;

[0074] Scheme 2: D2 is 85 mm and b2 is 42.8 mm;

[0075] Scheme 3: D2 is 87.5 mm and b2 is 42.8 mm;

[0076] That is, the width-diameter ratios are 0.519, 0.506, and 0.439 respectively, and the range of the width-diameter ratio is limited to 0.4 - 0.6. The actual characteristic curves of the ventilator 10 are respectively measured and compared with the prototype. The summary charts obtained from the experimental data of the above three schemes are as Figure 22 shown.

[0077] From Figure 22 the experimental data, it can be observed that under the condition of equal air volume, the smaller the profile shape parameter, the greater the maximum static pressure that can be achieved. For this volute, the impeller 200 with D2 of 82.5 mm (Scheme 1) cannot reach the ideal outlet static pressure. In terms of flow rate, the overall level of the impeller 200 with D2 of 85 mm and b of 42.8 mm, that is, a width-diameter ratio of 0.439, is better.

[0078] In the design of the fan 10, the higher the static pressure, the stronger the ability of the system to overcome resistance. To further verify this result, relevant simulation experiments were also carried out. For details, please refer to Figures 17 to 19 . It can be seen from Figure 17 that the static pressure increases with the decrease of the profile coefficient, reaches the maximum value near the outer wall of the volute, and fluctuates greatly near the outlet of the impeller 200. The larger the diameter of the impeller 200 in the scheme and the smaller the profile shape parameters, the relatively higher the static pressure in the whole flow field, the proportion of the static pressure in the total pressure increases, and the energy loss of the dynamic pressure converted into static pressure in the volute and the flow of the gas in the pipeline after leaving the fan 10 is reduced. Therefore, the first scheme with a smaller diameter D2 of 82.5 mm and b2 of 42.8 mm cannot meet the outlet static pressure requirement.

[0079] For the side of the impeller 200 facing away from the air inlet 101, as Figure 18 and 19 can be seen, there is a large low-speed area at the outlet of the volute of the fan 10, indicating that the flow separation situation is relatively serious at this place. Moreover, with the decrease of the profile shape parameters, the influence of the separation vortex is more significant, resulting in a decrease in the outlet flow rate. At the same time, the increase in the diameter of the impeller 200 will lead to a decrease in the distance between the impeller 200 and the volute, especially on the side close to the volute, where there is a smaller gap. Some of the airflows that do not flow out smoothly from the outlet cannot enter the flow channel between the volute and the impeller 200 again, which will cause a local high-pressure area in the outlet area of the volute, generating a large backflow driving force and affecting the outlet effect of the fan 10.

[0080] Therefore, among the three schemes, the impeller 200 with D2 of 85 mm, b2 of 42.8 mm, and a width-diameter ratio of 0.439 can maintain a large flow rate while providing a large outlet static pressure, and has good wind resistance.

[0081] In an embodiment, the ratio between the outlet height of the volute assembly 100 and the outer diameter of the impeller 200 is not less than 0.6 and not greater than 0.7. In this embodiment, by optimizing the hydrodynamic performance, reducing noise and vibration, improving the pressure and flow characteristics, facilitating design and manufacturing, and having wide adaptability, the overall performance and reliability of the centrifugal fan 10 or the centrifugal pump can be significantly improved.

[0082] To verify the technical effects achieved by the fan 10 in this embodiment, under the same number of blades 220 and working conditions, the fan 10 of the present invention and the conventional fan 10 were respectively tested. The following is the process of the experiment:

[0083] Exemplarily, taking the air outlet 102 of the fan 10 as a rectangle, the height of the volute outlet is the same as the overall height of the volute. The height of the impeller 200 is selected as 42.8 mm according to the above scheme b2. Due to the limitation of the position matching of the motor bearing for the impeller 200, different outlet heights B represent the distance difference between the impeller 200 and the wall surface of the air inlet 101 of the volute. The diameter of the impeller 200 is selected as 85 mm according to the above scheme D2. The diameter of the impeller 200 and the height of the volute outlet jointly affect the aerodynamic performance of the fan 10. Setting the outer diameter of the impeller 200 as D2 and the height of the volute as B, define the dimensionless position matching parameter:

[0084] Using a power of 60 W, three measurement schemes are set as follows:

[0085] Scheme 1: B is 52 mm and D2 is 85 mm;

[0086] Scheme 2: B is 55 mm and D2 is 85 mm;

[0087] Scheme 3: B is 58 mm and D2 is 85 mm;

[0088] That is, the ratios of the height B of the volute to the outer diameter D2 of the impeller 200 are 0.61, 0.65, and 0.68 respectively, and the range of the ratio of the height B of the volute to the outer diameter D2 of the impeller 200 is limited to 0.6 - 0.7. The actual characteristic curves of the ventilator 10 are measured respectively and compared with the prototype. The summary charts obtained from the experimental data of the above three schemes are as Figure 21 shown.

[0089] It can be observed from the experimental data that when B is 55 mm, D2 is 85 mm, and the ratio of the height B of the volute to the outer diameter D2 of the impeller 200 is 0.65, the volute has a significant advantage in the flow rate in the low-pressure area. The air volume under each working condition first increases and then decreases with the increase of the outlet height B. Therefore, it can be evaluated as the optimal volute matching height at this impeller 200 diameter.

[0090] To further verify this result, relevant simulation experiments are also carried out. Select the working condition point where the outlet static pressure P is 0 Pa. For the simulation results, please refer to Figure 20 . From Figure 20 it can be seen that too low a volute will cause a large separation vortex to form at the upper end of the impeller 200 for the air flow entering from the air inlet 101, hindering the air flow from passing through the gap of the impeller 200. Too high a volute will cause a large air flow to deflect greatly when entering the rotation area of the impeller 200, and deflect towards the position close to the outlet, with very little air intake on the other side, resulting in limited overall utilization rate of the impeller 200. At the same time, a relatively obvious velocity separation vortex is formed at the position of the blade 220, hindering the air flow from passing through the blade 220 and seriously affecting the overall air flow field of the fan 10. Therefore, among the above three schemes, the volute with B being 55 mm and 0.65 has a relatively high utilization rate and a relatively smooth flow field.

[0091] In one embodiment, please refer to Figure 11 , in order to ensure that the fan 10 has sufficient air intake, the gap between the inner wall on the side of the air inlet 101 of the volute assembly 100 and the impeller 200 is not less than 3 mm and not more than 6 mm. That is Figure 11 , the gap at A is not less than 3 mm and not more than 6 mm, and specifically can be 3 mm, 4 mm, 5 mm or 6 mm. Thus, within this range, it is possible to have a better air intake while reducing the backflow of air.

[0092] The present utility model also proposes a fan assembly 1, which can be applied to water heaters (especially gas water heaters), range hoods, air treatment devices, etc., and will not be exemplified one by one here. The specific structure of the fan assembly 1 will be described below.

[0093] Please refer to Figure 3 and Figure 4 , in one embodiment of the present utility model, the fan assembly 1 includes a fan 10 and a driving motor 20. The fan 10 includes a volute assembly 100 and an impeller 200 disposed in the volute assembly 100. The driving motor 20 includes a stator assembly 21 and a rotor assembly 22 disposed in the stator assembly 21. The volute assembly 100 and the stator assembly 21 are integrally formed, and the rotor assembly 22 is drivingly connected to the impeller 200.

[0094] Regarding the driving motor 20, the driving motor 20 generally includes a motor housing, a stator assembly 21 and a rotor assembly 22. The motor housing is used to protect internal components such as the stator assembly 21 and the rotor assembly 22, and provide mechanical support. In this embodiment, by integrally forming the stator assembly 21 with the volute assembly 100, the motor housing, the connection structure between the motor housing and the stator assembly 21, and the connection structure between the motor housing and the volute assembly 100 are reduced, thereby simplifying the installation structure of the driving motor 20 in the fan assembly 1.

[0095] Regarding the integral formation of the volute assembly 100 and the stator assembly 21, the volute assembly 100 and the stator assembly 21 are integrally formed. The volute assembly 100 includes a volute main body 110 and a cover plate 120, and the volute main body 110 generally includes a bottom plate and a surrounding plate. Thus, the integral formation of the volute assembly 100 and the stator assembly 21 can be that the stator assembly 21 is integrally formed with the cover plate 120, or the stator assembly 21 is integrally formed with the bottom plate. Additionally, in some special embodiments, it can also be that the stator assembly 21 is integrally formed with the surrounding plate. Preferably, for arranging the structural layout of the fan assembly 1 reasonably, the stator assembly 21 is integrally formed with the cover plate 120.

[0096] It should be understood that in this embodiment, the integrally formed volute component 100 and the stator component 21 are designed to achieve the manufacture of an integral structure through single processing or a combination of various processing methods, avoiding the defects brought by the traditional assembly or welding methods of the volute component 100 and the stator component 21. The ways of integrally forming the volute component 100 and the stator component 21 include but are not limited to injection molding, 3D printing, etc.

[0097] The technical solution of the present utility model integrally forms the stator component 21 of the driving motor 20 and the volute component 100 of the blower 10, so that the driving motor 20 does not need connecting parts such as screws for fixed installation, thus simplifying the installation structure of the driving motor 20 in the blower assembly 1.

[0098] Furthermore, integrally forming the stator component 21 and the volute component 100 has significant advantages in many applications, including weight reduction, improved structural rigidity, simplified manufacturing and assembly processes, and system reliability, etc.

[0099] For example, please refer to Figure 4 and Figure 9 , in an exemplary embodiment, the volute component 100 includes a volute main body 110 and a cover plate 120. The volute main body 110 and the cover plate 120 enclose a blower cavity for installing the impeller 200, and the cover plate 120 and the stator component 21 are integrally formed.

[0100] Furthermore, the cover plate 120 includes a plate body 121 and a protruding portion 122 provided on the plate body 121. The plate body 121 and the volute main body 110 enclose a blower cavity; the protruding portion 122 is arranged in a ring shape, the protruding portion 122 covers the stator component 21 and is integrally formed with the stator component 21, and the protruding portion 122 encloses a motor cavity for installing the rotor component 22. Preferably, in order to further reduce the axial height of the blower assembly 1, at least part of the protruding portion 122 is arranged in the blower cavity.

[0101] Among them, at least part of the convex portion 122 is disposed in the fan cavity. Since the convex portion 122 encloses a motor cavity for installing the rotor assembly 22, that is to say, part of the drive motor 20 is located in the fan cavity, thereby reducing the axial height of the fan assembly 1. The axial height generally refers to the axial height of the fan assembly 1 along the axis 22a of the drive motor 20. At least part of the convex portion 122 being disposed in the fan cavity can be understood as that the convex portion 122 is entirely placed in the fan cavity, or part of the convex portion 122 is disposed in the fan cavity, and part of the convex portion 122 can be in the direction of the axis 22a of the drive motor 20. Specifically, for example, half of the convex portion 122 is disposed in the fan cavity, or one-third of the convex portion 122 is disposed in the fan cavity, and so on. Of course, it can also be other parts. For example, the motor cavity generally includes a first bearing cavity, a main cavity, and a second bearing cavity. Among them, the convex portion 122 corresponding to the first bearing cavity can be accommodated in the fan cavity.

[0102] In an exemplary embodiment, please refer to Figure 15 and 16 , the convex portion 122 includes a first convex sub-portion 122a and a second convex sub-portion 122b. The first convex sub-portion 122a and the second convex sub-portion 122b are respectively disposed on both sides of the plate body 121. The first convex sub-portion 122a is disposed close to the impeller 200, and the second convex sub-portion 122b is disposed away from the impeller 200. The first convex sub-portion 122a is received in the receiving groove 201, and the second convex sub-portion 122b covers the stator assembly 21.

[0103] In another exemplary embodiment, please refer to Figure 7 and Figure 9 , the rotor assembly 22 includes a rotating shaft 22a, a rotor core 22b sleeved on the rotating shaft 22a, a first bearing 22c, and a second bearing 22d. The first bearing 22c, the rotor core 22b, and the second bearing 22d are arranged in sequence along the axis of the rotating shaft 22a; the first convex sub-portion 122a constructs a first bearing cavity for installing the first bearing 22c, the second convex sub-portion 122b constructs a main cavity for installing the rotor core 22b, and the end cover 23 constructs a second bearing cavity for installing the second bearing 22d. The first bearing cavity, the main cavity, and the second bearing cavity communicate to form a motor cavity.

[0104] In one embodiment, in order to shorten the length of the rotating shaft 22a in the rotor assembly 22, the impeller 200 has a first end and a second end disposed opposite to each other. The first end is close to the cover plate 120, and the hub 210 is disposed at the first end of the impeller 200.

[0105] In another embodiment, please continue to refer to Figure 3 and Figure 4 , Figure 7 and Figure 9, in order to further shorten the length of the rotating shaft 22a in the rotor assembly 22, a receiving groove 201 is provided on one side of the hub 210 close to the cover plate 120, and at least part of the protruding portion 122 is disposed in the receiving groove 201.

[0106] In another embodiment, an opening 104 communicating with the motor cavity is provided at one end of the protruding portion 122 facing away from the plate body 121. The driving motor 20 includes an end cover 23 for covering the opening 104; for the convenience of disassembly and assembly of the rotor assembly 22, the end cover 23 and the protruding portion 122 are detachably connected.

[0107] In another embodiment, in order to ensure good reliability and sealing performance of the connection between the end cover 23 and the protruding portion 122, the end cover 23 and the protruding portion 122 are riveted. In this embodiment, the riveting connection between the end cover 23 and the protruding portion 122 can be understood as an interference fit connection between the end cover 23 and the protruding portion 122. Among them, the riveting connection between the end cover 23 and the protruding portion 122 enables the blower assembly 1 to be free from the influence of environmental factors (such as temperature, humidity, vibration, etc.), has good fatigue resistance and seismic resistance, is suitable for structures for long-term use, and is suitable for use scenarios such as water heaters.

[0108] Furthermore, a limiting step is provided on the inner wall of the protruding portion 122 near the opening 104. The limiting step includes a horizontal step surface and a vertical step surface connected to each other; the end cover 23 includes an end portion 23a, a limiting portion 23b, and an abutting portion 23c connected in sequence. The end portion 23a constructs a second bearing cavity; the limiting portion 23b is in limiting abutment with the limiting step on the horizontal step surface, and the abutting portion 23c is in abutment with the limiting step on the vertical step surface. In this way, the setting of the horizontal step surface limits the connection position between the end cover 23 and the protruding portion 122, so that it will not be inserted into the motor cavity excessively. The vertical step surface is used to abut against the abutting portion 23c. That is to say, the abutting portion 23c and the protruding portion 122 are in interference fit on the vertical step surface.

[0109] It can be understood that the horizontal step surface refers to the surface of the protruding portion 122 at the position of its opening 104 perpendicular to the axis of the rotating shaft 22a of the driving motor 20, and the vertical step surface refers to the surface of the protruding portion 122 at the position of its opening 104 parallel to the axis of the rotating shaft 22a of the driving motor 20.

[0110] It is worth mentioning that there are many installation methods for the volute main body 110 and the cover plate 120. For example, welding, or adhesive bonding, or, pin and snap connection, etc.

[0111] However, since the strength of the welding part 111 is usually lower than that of the base material, and the cover plate 120 is usually also used to install components such as the impeller 200 and the motor. If the welding quality at the connection between the cover plate 120 and the volute main body 110 is not good, it may become a weak link in the structure, thus affecting the stability of the structures of the cover plate 120 and the volute main body 110.

[0112] In one embodiment, the volute component 100 includes a volute main body 110, a cover plate 120, and an insert 130. The volute main body 110 has an installation opening 103; the cover plate 120 is used to cover the installation opening 103; the insert 130 is integrally formed with the cover plate 120, and the insert 130 is connected to the volute main body 110 by welding or bonding.

[0113] In this embodiment, in order to reduce the weight of the fan component 1 and reduce the manufacturing cost, the materials of the volute main body 110 and the cover plate 120 are usually plastics.

[0114] Since the cover plate 120 is integrally formed with the stator assembly 21, the material of the cover plate 120 needs to have good insulation performance and arc resistance. Therefore, the material of the cover plate 120 is usually BMC material. BMC (Bulk Molding Compound) is a composite material. Of course, the materials of the plate body 121 and the protrusion 122 can also be other materials with properties similar to BMC material, such as SMC (Sheet Molding Compound) material, SMC / BMC hybrid composite material, or DMC (Dough Molding Compound) material, etc., which will not be exemplified one by one here. However, the cost of BMC material is relatively high and it is not easy to demold, and the volute main body 110 does not require good insulation performance and arc resistance. Therefore, the material of the volute main body 110 is usually selected as ordinary plastic.

[0115] Since the volute main body 110 and the cover plate 120 need to use different materials. And different materials have melting point differences. During the welding process, one material may have melted while the other material has not reached the melting point, which will cause uneven welding and form an insecure joint, resulting in poor connection stability between the volute main body 110 and the cover plate 120. In this implementation, by making the material of the insert 130 the same as that of the volute main body 110, the insert 130 is integrally formed with the cover plate 120. Thus, the problem of poor connection stability caused by different materials of the cover plate 120 and the volute main body 110 can be solved.

[0116] Regarding the integral molding of the insert 130 and the cover plate 120, the integral molding method of the insert 130 and the cover plate 120 includes but is not limited to injection molding and 3D printing, etc. Preferably, the insert 130 and the cover plate 120 are integrally injection molded.

[0117] Regarding the welding connection or bonding of the insert 130 and the volute main body 110, the bonding between the insert 130 and the volute main body 110 usually refers to adhesive bonding. By using this method, the insert 130 and the volute main body 110 can distribute stress over a larger contact area, reducing local stress concentration and lowering the risk of material fatigue and fracture. Secondly, it can also provide excellent sealing performance to prevent fluid leakage. In addition, the adhesive bonding process is relatively simple, does not require complex equipment and processes, and reduces processing costs and time. The insert 130 and the volute main body 110 are connected by welding. Among them, the welding connection usually uses ultrasonic welding, laser welding, etc. By using this method, the welding of the insert 130 and the volute main body 110 can provide a high-strength permanent connection, and the welded joint can usually withstand high-temperature environments and is suitable for equipment under high-temperature operating conditions.

[0118] In the above, the choice of whether to use adhesive bonding or welding for the connection between the insert 130 and the volute main body 110 should be determined according to specific application requirements and conditions. If the power required by the scenario where the fan assembly 1 is applied is large and it is a high-temperature operation scenario, welding would be a better choice. If the scenario where the fan assembly 1 is applied requires good sealing performance, corrosion resistance, shock absorption and noise reduction effects, and the operating conditions do not allow high temperature, adhesive bonding may be more suitable.

[0119] In this way, in this embodiment, the volute main body 110 and the cover plate 120 are connected by the insert 130. The insert 130 is integrally formed with the cover plate 120. The insert 130 is welded or bonded to the volute main body 110. When the insert 130 is welded to the volute main body 110, a material with better strength is selected for the insert 130 to ensure the structural stability of the cover plate 120 and the volute main body 110. When the insert 130 is bonded to the volute main body 110, a material more suitable for bonding can be selected for the insert 130 to ensure the tightness and stability of the structural connection between the cover plate 120 and the volute main body 110. The setting of the insert 130 also makes the application range of the volute assembly 100 more extensive.

[0120] In a preferred embodiment, please refer to Figure 7 and Figure 8 , the volute main body 110 has a first fitting surface that fits the insert 130 and the cover plate 120; a welding portion 111 is provided on the first fitting surface of the volute main body 110, and a welding groove 131 adapted to be installed with the welding portion 111 is provided on the insert 130; or, a welding groove 131 is provided on the first fitting surface of the volute main body 110, and a welding portion 111 adapted to be installed with the welding groove 131 is provided on the insert 130. Among them, the welding groove 131 is usually an annular groove surrounding the mounting opening 103. Preferably, the number of welding grooves 131 is multiple, and the multiple welding grooves 131 are arranged side by side. Among them, the number of welding grooves 131 can be two, three, four, five, six or more than six.

[0121] In one embodiment, please refer to Figure 9 and Figure 11 , to ensure the stability of the welding between the cover plate 120 and the volute main body 110, the insert 130 is arranged in a ring shape, and the insert 130 surrounds the cover plate 120. In other embodiments, the insert 130 may also be formed by arranging a plurality of insert segments along the outer periphery of the cover plate 120.

[0122] In one embodiment, please refer to Figure 5 and Figure 14 , the volute main body 110 has an air outlet 102, and the air outlet 102 communicates with the installation port 103. To ensure the stability of the welding between the cover plate 120 and the volute main body 110, the end face of the insert 130 is flush with the end face of the air outlet 102.

[0123] In one embodiment, please refer to Figure 2 , Figure 4 and Figure 9 , to facilitate the installation and positioning of the cover plate 120 and the volute main body 110, a flange 112 is provided on the outer peripheral side of the volute main body 110 near the air outlet 102, and the insert 130 is provided with an avoidance groove corresponding to the position of the flange 112. Alternatively, the cover plate 120 is provided with an avoidance groove corresponding to the position of the flange 112. Specifically, please refer to Figure 4 , through the setting of the flange 112, when installing the cover plate 120, the flange 112 can be used as a positioning point, thereby facilitating the installation and positioning of the cover plate 120 and the volute main body 110.

[0124] In a preferred embodiment, please refer to Figure 11 , the insert 130 is further provided with a fastening portion 132, and the fastening portion 132 is integrally formed with the cover plate 120. Through the setting of the fastening portion 132, after the insert 130 and the cover plate 120 are integrally formed, the connection area between the insert 130 and the cover plate 120 is increased, thereby making the connection between the insert 130 and the cover plate 120 more stable.

[0125] Furthermore, the fastening portion 132 is a groove provided on the insert 130, and / or the fastening portion 132 is a protrusion provided on the insert 130. The shapes of the groove and the protrusion can be regular shapes such as cylindrical or square-columnar, or other irregular shapes, and will not be exemplified one by one here.

[0126] Furthermore, the number of the fastening portions 132 is multiple, and the multiple fastening portions 132 are arranged at intervals along the circumferential direction of the insert 130. Preferably, the multiple fastening portions 132 are evenly arranged at intervals along the circumferential direction of the insert 130.

[0127] In another preferred embodiment, in order to facilitate the welding of the insert 130 and the volute main body 110, steps are formed on the circumferential sides of the insert 130 and the volute main body 110 at their connection. That is to say, the circumferential sides at the connection of the insert 130 and the volute main body 110 are not aligned, so that the welding head can be better positioned between the insert 130 and the volute main body 110.

[0128] In one embodiment, the distance between the circumferential side of the insert 130 and the circumferential side of the volute main body 110 is not greater than 5 mm and not less than 3 mm. Specifically, the distance between the circumferential side of the insert 130 and the circumferential side of the volute main body 110 includes, but is not limited to, 3.0 mm, 3.2 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.8 mm, 4.0 mm, 4.2 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.8 mm or 5.0 mm.

[0129] In yet another embodiment, please refer to Figure 7 and Figure 8 , in order to facilitate the positioning and installation of the cover plate 120 and the volute main body 110, and improve the sealing performance between the cover plate 120 and the volute main body 110. The cover plate 120 includes a plate body 121, a fitting portion 123 and a positioning portion 124. The fitting portion 123 is arranged around the plate body 121, and the fitting portion 123 is in contact with the end face of the volute main body 110 at the installation opening 103; the positioning portion 124 is arranged at the connection of the plate body 121 and the fitting portion 123, and the positioning portion 124 is a protrusion facing the volute main body 110. Among them, the setting of the positioning portion 124 enables the positioning and installation of the cover plate 120 and the volute main body 110 to be faster. The fitting portion 123 is in contact with the volute main body 110 on the first contact surface. The settings of the fitting portion 123 and the positioning portion 124 form a radial seal between the cover plate 120 and the volute main body 110, thereby improving the sealing performance at the connection of the cover plate 120 and the volute main body 110.

[0130] In one embodiment, the fan assembly 10 further includes a connection assembly 300. The connection assembly 300 is used to install the volute assembly 100 on an installation carrier. Among them, the installation carrier refers to, for example, the support main body of a water heater, the support main body of a range hood, or the support main body of an air treatment device, etc. It mainly depends on the scenario where the fan 10 is applied. Here, the water heater is taken as an example for introduction.

[0131] Please refer to Figure 4 or Figure 9 , the connection assembly 300 is arranged at the air outlet 102 of the volute. The connection assembly 300 includes an insert 310 and a connecting piece 320. The insert 310 is integrally formed with the volute, and the connecting piece 320 is connected to the insert 310. The connecting piece 320 is used to connect with the support carrier of the water heater to install the volute on the support carrier of the water heater.

[0132] Among them, in this embodiment, the volute generally includes a volute main body 110 and a cover plate 120. In this embodiment, the materials of the volute main body 110 and the cover plate 120 are plastics. In order to ensure the strength of the connection between the volute assembly 100 and the installation carrier, in this embodiment, an insert 310 is further provided. The insert 310 generally requires greater strength. Therefore, the material of the insert 310 usually selects a material with greater strength, such as metals with greater strength, such as carbon steel, stainless steel, and alloy steel, etc. Of course, the insert 310 can also be other non-metallic materials with greater strength.

[0133] In this embodiment, by setting the insert 310 at the air outlet, the strength of the insert 310 is greater than that of the volute, and the insert 310 is integrally formed with the volute. The volute is connected and installed with the water heater main body at its air outlet 102. In this way, the technical solution of the present utility model improves the structural strength at the air outlet of the volute, thereby improving the stability and reliability of the connection between the volute assembly 100 and the water heater main body.

[0134] It can be understood that the connection between plastic parts and metal parts is generally not as firm as the connection between metal parts and metal parts. Especially in this embodiment, the cover plate is also used to install the driving motor 20. When the fan assembly 10 works, the motor will generate vibration or mechanical shock.

[0135] In an exemplary embodiment, the volute includes a volute main body 110 and a cover plate 120. The volute main body 110 has an installation opening 103, the cover plate 120 covers the installation opening 103, the insert 310 is embedded in the volute main body 110, the volute main body 110 is a plastic part, and the insert 310 is a metal part.

[0136] Furthermore, in order to improve the stability of the connection between the insert 310 and the volute main body 110, the insert 310 includes an insert body 311 and an embedding portion 312 provided on the insert body 311. The embedding portion 312 is embedded in the volute assembly 100 and is integrally formed with the volute assembly 100. Through the setting of the embedding portion 312, the connection area between the insert 310 and the volute main body 110 is increased, thereby improving the stability of the connection between the insert 310 and the volute main body 110.

[0137] Among them, the embedding portion 312 is embedded in the volute assembly 100 from the end face at the air outlet 102. Or, the embedding portion 312 is embedded in the volute assembly 100 from the circumferential side at the air outlet 102. Preferably, the embedding portion 312 is embedded in the volute assembly 100 from the end face at the air outlet 102. At this time, for the embedding portion 312 with the same shape and size, the scheme of embedding the embedding portion 312 in the volute assembly 100 from the end face at the air outlet 102 has the largest connection area between the embedding portion 312 and the volute assembly 100.

[0138] Further, in order to further improve the connection stability between the insert 310 and the volute main body 110, the insert 310 further includes a reinforcement portion 313, and the reinforcement portion 313 is provided on the insertion portion 312. Through the arrangement of the reinforcement portion 313, the connection area between the insert 310 and the volute assembly 100 is further increased, thereby further improving the stability of the connection between the insert 310 and the volute main body 110. Among them, the reinforcement portion 313 can be a protrusion provided on the insertion portion 312 or a hole provided on the insertion portion 312. Preferably, the insertion portion 312 is provided in a sheet shape, and the reinforcement portion 313 is a through hole penetrating the insertion portion 312.

[0139] In another preferred embodiment, the number of the insertion portions 312 is multiple, and the multiple insertion portions 312 are arranged at intervals along the circumferential direction of the insert body 311. Preferably, the multiple insertion portions 312 are evenly arranged at intervals along the circumferential direction of the insert body 311.

[0140] In an exemplary embodiment, please refer to Figure 9 , the connecting member 320 includes a connecting frame 321, a connecting portion 322 and a clamping portion 323 provided on the connecting frame 321; the connecting frame 321 and the insert body 311 are connected by fasteners, the connecting portion 322 is used to connect with the mounting carrier through fasteners, and the clamping portion 323 is used to clamp with the mounting carrier. Thus, through the arrangement of the connecting portion 322 and the clamping portion 323, when installing the fan assembly 1, first use the clamping portion 323 to perform alignment clamping, and then the connecting portion 322 is fixed to the mounting carrier through fasteners. In this way, it is not only convenient for the installation and alignment of the fan assembly 1, but also can ensure the stability and tightness of the connection between the fan assembly 1 and the mounting carrier to a certain extent.

[0141] Based on the previous embodiment, please continue to refer to Figure 9 , the connecting portion 322 includes a connecting sub-portion 322a and a folding sub-portion 322b that are connected to each other. The connecting sub-portion 322a is connected to the connecting frame 321, and the folding sub-portion 322b is folded toward the side of the volute assembly 100. Preferably, in order to enhance the connection strength of the connecting member 320, the connecting frame 321 is further provided with a flanging 324.

[0142] In one embodiment, the volute assembly 100 has an air inlet 101. In order to facilitate the installation of the volute assembly 100 and the mounting carrier, the installation position is provided on the side of the volute assembly 100 where the air inlet 101 is provided, and the clamping member 330 is provided on the side of the volute assembly 100 away from the air inlet 101. In order to ensure the smoothness of the air inlet, there are usually fewer obstacles on one side of the air inlet 101. Setting the installation position on the side of the volute assembly 100 where the air inlet 101 is provided can prevent other obstacles from hindering the installation of the volute assembly 100.

[0143] It should be understood that the installation position can be an installation groove, an installation hole, an installation post, etc. Preferably, the insert 310 is a nut. Of course, in other embodiments, the insert 310 can also be a threaded connector 320 such as a bolt or a stud.

[0144] The present utility model also provides a water heater, which includes a water heater main body and a fan assembly 1. The specific structure of the fan assembly 1 refers to the above embodiments. Since the fan 10 of the present utility model adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated one by one here.

[0145] Among them, the water heater with the fan assembly 1 is usually a gas water heater and is a water heater with a forced exhaust function. Its main structure includes a burner, a heat exchanger, the fan assembly 1, a control system and other auxiliary components. The fan assembly 1 is usually installed at the top, bottom or side of the water heater and is connected to the combustion chamber and the exhaust system. The specific position design of the fan 10 is related to the structure and model of the water heater. The fan 10 is fixed to the outer shell or the internal frame of the water heater by means of screws, brackets or buckles to ensure its stability. Gas path connection: The air inlet of the fan 10 is connected to the combustion chamber to provide the air required for combustion; the air outlet is connected to the exhaust pipe to discharge the combustion waste gas.

[0146] The above are only exemplary embodiments of the present utility model, and do not limit the patent scope of the present utility model. Any equivalent structural transformation made by using the content of the specification and drawings of the present utility model under the technical concept of the present utility model, or direct / indirect application in other related technical fields is included in the patent protection scope of the present utility model.

Claims

1. A fan, characterized in that: include: A volute assembly, comprising a fan cavity, and an air inlet and an air outlet communicated with the fan cavity, wherein the volute comprises a volute tongue arranged corresponding to the air outlet; An impeller, the impeller being arranged in the fan chamber, the impeller comprising at least two layers of blade groups arranged in the axial direction, each of the blade groups comprising a plurality of blades arranged at intervals in the circumferential direction of the impeller, the blades of two adjacent layers of the blade groups being arranged in a staggered manner, and the volute tongue gap between the volute tongue and the impeller being arranged in a non-equidistant manner in the axial direction of the volute assembly; The outlet height of the impeller is the sum of the vertical distances from the outlet edge of any blade in each layer of the blade group to the central axis of the impeller. The ratio between the outlet height of the impeller and the outer diameter of the impeller is the aspect ratio, and the aspect ratio is not less than 0.4 and not more than 0.

6.

2. The fan according to claim 1, characterized in that: In the axial direction of the volute assembly, the volute tongue clearance gradually increases or decreases from one end of the volute assembly toward the other end.

3. The fan according to claim 1, characterized in that: The volute assembly has two ends that are arranged opposite to each other along its axial direction, and the volute tongue gap gradually decreases from the two ends to the middle of the volute assembly.

4. The fan according to claim 3, characterized in that: In the axial direction of the volute assembly, the volute tongue gap corresponding to the center position of the volute tongue is the smallest.

5. The fan according to claim 1, characterized in that: The ratio between the outlet height of the volute assembly and the outer diameter of the impeller is not less than 0.6 and not more than 0.

7.

6. The fan according to claim 1, characterized in that: The volute assembly is provided with a gap between the inner wall on one side of the air inlet and the impeller that is not less than 3 mm and not more than 6 mm.

7. The fan according to any one of claims 1 to 6, characterized in that: The volute assembly further includes a volute body and a cover plate, wherein the volute body has a mounting opening, and the cover plate is sealed on the mounting opening; The cover plate includes a plate body and a raised portion arranged on the plate body, the plate body and the volute body enclose the fan cavity; the raised portion is arranged in a ring shape, the raised portion covers the stator assembly of the motor, the raised portion and the stator assembly are integrally formed, and the raised portion encloses a motor cavity for installing the rotor assembly of the motor.

8. The fan according to claim 7, characterized in that: The volute further comprises an insert, which is integrally formed with the cover plate and connected to the volute body.

9. A water heater, characterized in that: The invention comprises a fan as claimed in any one of claims 1 to 8.

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