Centrifugal fan suitable for range hood and impeller assembly

Abstract

The centrifugal fan and impeller assembly suitable for the range hood comprises a volute and an impeller assembly, and the volute comprises an air inlet; an air guide ring is arranged at the air inlet and is provided with an arc air guide edge; the impeller assembly comprises a fixed disc and at least one fixed ring which are coaxially arranged in parallel, and a plurality of blades which are connected between the fixed disc and the fixed ring and are axially arranged at intervals; each blade comprises an inner edge, an outer edge and an end part close to the fixed disc; an air guide part is arranged at the position, close to the end part, of the inner edge and obliquely extends from the end part to the fixed disc, and the inclination direction of the air guide part deviates from the inner edge to the outer edge; the fixing ring comprises an inner ring and an outer ring; the inner edges of the blades exceed the inner ring and are positioned on the inner side of the fixing ring; the inner side of the end part is positioned below the fixing ring; the arc air guide edge is bent inwards to the side of the air guide part, so that a smooth air inlet path is formed, air flow is more effectively guided to enter the impeller assembly, the loss of the air flow is reduced, and the suction force and the smoke exhaust effect of the range hood are improved.

Description

Technical Field

[0001] This utility model relates to the technical field of range hoods, and in particular to a centrifugal fan and impeller assembly suitable for range hoods. Background Technology

[0002] In the field of range hoods and ventilation equipment, the performance of the impeller assembly has a crucial impact on the overall aerodynamic efficiency and noise level of the machine. While significant progress has been made in the design of impeller assemblies in the existing technology, there is still room for improvement in addressing the inlet turbulence problem when airflow enters the impeller.

[0003] For example, utility model patent CN212003716U discloses an impeller for a centrifugal fan. This impeller, by creating through holes and installing guide vanes in the central plate, can increase airflow and reduce operating noise without changing the overall size of the impeller or adding materials. However, this design mainly focuses on guiding airflow inside the impeller and does not provide an effective solution to the inlet turbulence problem when airflow enters the impeller.

[0004] For example, patent application CN114370427A proposes an impeller that uses a shielding surface on the front disc to suppress backflow vortices at the top of the blades, thereby improving airflow smoothness and reducing noise. Although this design improves airflow characteristics to some extent, it mainly addresses the backflow problem at the top of the blades, rather than the inlet turbulence when the airflow enters the impeller.

[0005] In summary, in existing impeller assemblies, turbulence at the inlet is still quite prevalent when airflow enters, which not only leads to airflow loss but also significantly affects the aerodynamic performance of the impeller. Therefore, developing an improved scheme that can effectively reduce inlet turbulence and improve impeller efficiency has become an important issue in the current technological field. Utility Model Content

[0006] The purpose of this utility model is to provide a centrifugal fan and impeller assembly suitable for range hoods, aiming to solve the problems of severe turbulence and energy loss at the air inlet of existing range hoods.

[0007] The technical solution adopted by this utility model to solve the above-mentioned technical problems is: a centrifugal fan suitable for range hoods.

[0008] The device includes a volute and an impeller assembly. The volute includes an air inlet. An air guide ring with an arc-shaped guide edge is provided at the air inlet. The impeller assembly includes a fixed disk and at least one fixed ring arranged coaxially and parallel to each other, and a plurality of axially spaced blades connected between the fixed disk and the fixed ring. Each blade includes an inner edge, an outer edge, and an end near the fixed disk. An air guide portion is provided near the end of the inner edge, and the air guide portion extends obliquely from the end towards the fixed disk, with its oblique direction shifting from the inner edge to the outer edge.

[0009] The fixing ring includes an inner ring and an outer ring; the inner edge of the blade extends beyond the inner ring and is located inside the fixing ring; the inner side of the end is located below the fixing ring; the arc-shaped air guide edge bends inward to the side of the air guide portion, thereby forming a smooth air intake path.

[0010] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problem is: the width of the end is greater than two-thirds of the width of the blade body and less than one-sixth of the width of the blade body.

[0011] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is: the air guide is a sloping structure with a relative axial tilt angle of 15-40°.

[0012] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: air inlets are provided on both sides of the volute, and each air inlet is provided with an air guide ring;

[0013] The impeller assembly includes a first fixing ring and a second fixing ring located on both sides of the fixed disk; the blade includes a first end and a second end, and after the blade passes through the ring portion of the fixed disk, the first end is connected to the first fixing ring and the second end is connected to the second fixing ring;

[0014] The inner edge is provided with a first air guide near the first end. The first air guide extends obliquely from the first end to the second end, and its oblique direction is offset from the inner edge to the outer edge.

[0015] The inner edge is provided with a second air guide near the second end. The second air guide extends obliquely from the second end toward the first end, and its oblique direction is offset from the inner edge toward the outer edge.

[0016] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is: the end portion and the air guide portion are connected by an arc-shaped connecting portion.

[0017] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: the outer edge of the blade is provided with a serrated section, and the tooth height of the last tooth structure near the end is greater than that of the other teeth.

[0018] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: the outer edge of the blade is provided with a first serrated section, a straight section, and a second serrated section;

[0019] The straight section passes through the ring portion of the fixed disk and is located on both sides of the ring portion.

[0020] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is that the thickness of the blade gradually decreases from the inner edge to the outer edge.

[0021] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: an impeller assembly includes a fixed disk and at least one fixed ring arranged coaxially and parallel to each other, and a plurality of blades arranged axially spaced between the fixed disk and the fixed ring; the blades include an inner edge, an outer edge and an end near the fixed disk; the inner edge is provided with a guide section near the end position, the guide section extends obliquely from the end towards the fixed disk, and its oblique direction is offset from the inner edge towards the outer edge.

[0022] The retaining ring includes an inner ring and an outer ring; the inner edge of the blade extends beyond the inner ring and is located inside the retaining ring; the inner side of the end is located below the retaining ring.

[0023] The preferred technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: the thickness of the blade gradually decreases from the inner edge to the outer edge; the outer edge of the blade is provided with a serrated section;

[0024] The width of the end is greater than two-thirds of the width of the blade body and less than one-sixth of the width of the blade body.

[0025] The air guide section is a sloping structure with a relative axial tilt angle of 15-40°;

[0026] The end portion is connected to the air guide portion via an arc-shaped connection.

[0027] Compared with the prior art, the advantages of this utility model are: the design and positional relationship of the air guide ring and the air guide part can guide the airflow smoothly into the impeller, reduce the inlet impact, improve the aerodynamic performance of the whole machine, and the guide part makes the blades converge in the low-pressure area where the work done at the end is small, adjust the airflow speed and pressure matching, and can reduce the weight of the impeller without affecting the work area, thereby improving the overall performance of the impeller. Attached Figure Description

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will understand that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be construed as limiting the scope of the present invention. Furthermore, unless specifically indicated, the drawings are only schematic representations of the composition or structure of the described objects and may contain exaggerated depictions, and the drawings are not necessarily drawn to scale.

[0029] Figure 1 A three-dimensional structural diagram of a centrifugal fan suitable for range hoods;

[0030] Figure 2 Structure of an impeller assembly for a centrifugal fan suitable for range hoods Figure 1 ;

[0031] Figure 3 Structure of an impeller assembly for a centrifugal fan suitable for range hoods Figure 2 ;

[0032] Figure 4 A schematic diagram of the blades of an impeller assembly for a centrifugal fan suitable for range hoods. Figure 1 ;

[0033] Figure 5 A schematic diagram of the blades of an impeller assembly for a centrifugal fan suitable for range hoods. Figure 2 ;

[0034] Figure 6 This is a partial enlarged view of the blades of an impeller assembly for a centrifugal fan suitable for range hoods. Detailed Implementation

[0035] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely descriptive and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0036] It should be noted that similar labels in the following figures indicate similar items; therefore, once an item is defined in one figure, it will not be further defined and explained in subsequent figures.

[0037] In the description of this utility model, it should be noted that the terms "upper," "lower," "front," "rear," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the usual placement of the product during use. These may differ from the orientations in the accompanying drawings. They are used solely for the purpose of describing the utility model from the same reference and for simplification, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Similarly, "first" and "second" are used only for ease of understanding and have no other directional meaning; they should not be considered as limitations on this utility model.

[0038] like Figure 1-4 As shown, this embodiment discloses a centrifugal fan suitable for range hoods, including a volute 100 and an impeller assembly 200. This impeller assembly 200 includes a coaxially parallel fixed disk 1 and at least one fixed ring 2, and a plurality of axially spaced blades 3 connecting the fixed disk 1 and the fixed ring 2. Each blade 3 includes an inner edge S, an outer edge P, and an end T near the fixed disk 1. An air guide M is provided near the end T on the inner edge S, extending obliquely from the end T towards the fixed disk 1, with its oblique direction shifting from the inner edge S towards the outer edge P. As shown, the fixed ring 2 includes an inner ring a and an outer ring b. The inner edge S of the blade 3 extends beyond the inner ring a and is located inside the fixed ring 2, with the inner side of the end located below the fixed ring. This design of the air guide M allows the airflow to smoothly enter the impeller, reducing inlet impact and improving the overall aerodynamic performance. Furthermore, the airflow entering from the air inlet Y of the volute 100 can partially enter the airflow channel between the blades 3, thereby improving the impeller's aerodynamic performance.

[0039] An air guide ring 300 is provided at the air inlet Y of the volute 100, and the air guide ring 300 has an arc-shaped air guide edge h. Preferably, the arc-shaped air guide edge h bends inward to the side of the air guide part M of the fixed plate 1, thereby forming a smooth path. This air guide ring 300 design can more effectively guide the airflow into the impeller assembly 200, reduce airflow loss, and improve the suction and smoke extraction effect of the range hood.

[0040] When the airflow enters the impeller assembly 200 from the inlet Y of the volute 100, the airflow moves from the fixed ring 2 to the fixed disk 1, and after impacting the fixed disk 1, it turns and enters the airflow channel between the blades 3. The part of the blades 3 near the fixed disk 1 is the main working area, forming a high-pressure area. The guide section makes the width of the end T smaller than the width of the middle section of the blades 3. This design not only allows the blades 3 to converge in the low-pressure area at the end T where less work is done, adjusting the airflow velocity to match the pressure, but also reduces the weight of the impeller without affecting the working area, thereby improving the overall performance of the impeller.

[0041] Preferably, the width of the end T is designed to be greater than two-thirds and less than one-sixth of the width of the main body of the blade 3. This precise width control can achieve an optimal balance in terms of optimizing airflow inlet conditions, reducing airflow losses when entering the blade 3, ensuring the strength of the blade 3, improving the work efficiency of the blade 3, and enhancing the efficiency of the fan.

[0042] Preferably, such as Figure 4-5 As shown, the air guide section M has a sloping structure with a relative axial tilt angle of 15-40°. More preferably, the inner side of the end T is aligned with the inner ring a of the fixing ring 2. This alignment ensures the correct position of the blade 3 within the fixing ring 2 and prevents unnecessary turbulence from forming between the blade 3 and the fixing ring 2.

[0043] Preferably, the end section T and the guide section M are connected by an arc-shaped transition section N. This arc transition reduces airflow separation between the guide section M and the end section T, improving airflow smoothness. The guide section M, through its tapered surface design, forms a laminar boundary layer at the airflow inlet, delaying the turbulence transition point. Its 15° inclination angle, optimized through simulation, forms the optimal matching angle with the relative velocity vector at the impeller inlet, ensuring that the airflow impact angle θ ≤ 3°, significantly reducing separation losses.

[0044] In this embodiment, as Figure 1-4 As shown, the centrifugal fan has a dual-inlet structure, with air inlets Y on both sides of the volute 100. The impeller assembly 200 includes a first fixing ring 2a and a second fixing ring 2b located on both sides of the fixed disk 1. The blade 3 includes a first end T1 and a second end T2. After the blade 3 passes through the ring portion of the fixed disk 1, the first end T1 is connected to the first fixing ring 2a, and the second end T2 is connected to the second fixing ring 2b. A first air guide M1 is provided near the first end T1 on the inner edge S. The first air guide M1 extends obliquely from the first end T1 to the second end T2, and its oblique direction is offset from the inner edge S to the outer edge P. A second air guide M2 ​​is provided near the second end T2 on the inner edge S. The second air guide M2 ​​extends obliquely from the second end T2 to the first end T1, and its oblique direction is offset from the inner edge S to the outer edge P. This dual-direction air guide design can more effectively guide the airflow, reduce airflow loss at both ends of the blade 3, and further improve the performance of the fan.

[0045] like Figure 4-5 As shown, the outer edge P of blade 3 has a first serrated section k1, a straight section k2, and a second serrated section k3. The straight section k2 passes through the ring of the fixed disk 1 and is located on both sides of the ring. This outer edge P design can increase the strength of blade 3 while reducing airflow turbulence at the outer edge P of blade 3, thereby improving the efficiency of the fan. Figure 6 As shown, the height of the last tooth structure j near the end of the first sawtooth segment k1 and the second sawtooth segment k3 is greater than that of the remaining teeth g to provide support.

[0046] The thickness of blade 3 gradually decreases from the inner edge S to the outer edge P. This gradual thickness design helps to reduce the weight of blade 3 while maintaining its strength and stiffness. In addition, it can improve the elastic deformation capability of the outer edge P, disrupt the outlet vortex to reduce noise, and optimize the operating performance of the fan.

[0047] In summary, the impeller assembly 200 of this embodiment significantly improves the aerodynamic performance and operating efficiency of the fan by optimizing the shape and arrangement of the blades 3 and adding structures such as the air guide M, making it suitable for applications such as range hoods that require efficient airflow control.

[0048] This invention introduces a centrifugal fan and impeller assembly suitable for range hoods. Specific examples are used to illustrate the principle and implementation of this invention. The descriptions of the embodiments are merely for the purpose of helping to understand this invention and its core ideas. It should be noted that those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A centrifugal fan suitable for range hoods, characterized in that: The device includes a volute and an impeller assembly. The volute includes an air inlet. An air guide ring with an arc-shaped guide edge is provided at the air inlet. The impeller assembly includes a fixed disk and at least one fixed ring arranged coaxially and parallel to each other, and a plurality of axially spaced blades connected between the fixed disk and the fixed ring. Each blade includes an inner edge, an outer edge, and an end near the fixed disk. An air guide portion is provided near the end of the inner edge, and the air guide portion extends obliquely from the end towards the fixed disk, with its oblique direction shifting from the inner edge to the outer edge. The fixing ring includes an inner ring and an outer ring; the inner edge of the blade extends beyond the inner ring and is located inside the fixing ring; the inner side of the end is located below the fixing ring; the arc-shaped air guide edge bends inward to the side of the air guide portion, thereby forming a smooth air intake path.

2. A centrifugal fan suitable for range hoods according to claim 1, characterized in that: The width of the end is greater than two-thirds of the width of the blade body and less than one-sixth of the width of the blade body.

3. A centrifugal fan suitable for range hoods according to claim 1, characterized in that: The air guide section is a sloping structure with a relative axial tilt angle of 15-40°.

4. A centrifugal fan suitable for range hoods according to claim 1, characterized in that: The volute has air inlets on both sides, and each air inlet is equipped with an air guide ring. The impeller assembly includes a first fixing ring and a second fixing ring located on both sides of the fixed disk; the blade includes a first end and a second end, and after the blade passes through the ring portion of the fixed disk, the first end is connected to the first fixing ring and the second end is connected to the second fixing ring; The inner edge is provided with a first air guide near the first end. The first air guide extends obliquely from the first end to the second end, and its oblique direction is offset from the inner edge to the outer edge. The inner edge is provided with a second air guide near the second end. The second air guide extends obliquely from the second end toward the first end, and its oblique direction is offset from the inner edge toward the outer edge.

5. A centrifugal fan suitable for range hoods according to claim 1, characterized in that: The end portion is connected to the air guide portion via an arc-shaped connection.

6. A centrifugal fan suitable for range hoods according to claim 1, characterized in that: The outer edge of the blade is provided with a serrated section, and the height of the last tooth structure near the end is greater than that of the other teeth.

7. A centrifugal fan suitable for range hoods according to claim 4, characterized in that: The outer edge of the blade is provided with a first serrated section, a straight section, and a second serrated section; The straight section passes through the ring portion of the fixed disk and is located on both sides of the ring portion.

8. A centrifugal fan suitable for range hoods according to claim 1, characterized in that: The thickness of the blade gradually decreases from the inner edge to the outer edge.

9. An impeller assembly, characterized in that: It includes a fixed disk and at least one fixed ring arranged coaxially and parallel to each other, and a plurality of blades arranged axially spaced between the fixed disk and the fixed ring; the blades include an inner edge, an outer edge and an end near the fixed disk; the inner edge is provided with an air guide near the end position, the air guide extends obliquely from the end towards the fixed disk, and its oblique direction is offset from the inner edge towards the outer edge. The retaining ring includes an inner ring and an outer ring; the inner edge of the blade extends beyond the inner ring and is located inside the retaining ring; the inner side of the end is located below the retaining ring.

10. An impeller assembly according to claim 9, characterized in that: The thickness of the blade gradually decreases from the inner edge to the outer edge; the outer edge of the blade is provided with serrated sections; The width of the end is greater than two-thirds of the width of the blade body and less than one-sixth of the width of the blade body. The air guide section is a sloping structure with a relative axial tilt angle of 15-40°; The end portion is connected to the air guide portion via an arc-shaped connection.

Images