Volute mechanism of centrifugal fan

Abstract

The volute mechanism of the centrifugal fan comprises two sets of volute side plates arranged in parallel and a volute plate welded and fixed to the position, close to the outer end, between the two sets of volute side plates, the two ends, connected with the volute side plates, of the volute plate are each of an arc-shaped structure, and the radius of each arc-shaped structure is not smaller than 15 mm. The two ends, connected with the volute side plates, of the volute plate are each of an arc-shaped structure, so that airflow can smoothly flow in the volute, vortexes are avoided, meanwhile, the maximum kinetic energy is generated, the efficiency of the fan is improved, the temperature of an outlet of the fan is greatly reduced under the condition that the working condition, the air pressure and the air volume are the same, the motor current is reduced by 10%-15%, and the service life of the fan is prolonged. And the energy-saving effect is obvious.

Description

TECHNICAL FIELD

[0001] The utility model relates to centrifugal fan technical field, concretely is a volute mechanism of centrifugal fan. BACKGROUND

[0002] The volute is a fixed component of centrifugal fan, and its function is to successfully guide the airflow after leaving the centrifugal impeller to the volute outlet, and convert part of the dynamic pressure into static pressure. Due to the complexity of the flow in the volute, it is inevitable to cause flow loss of the airflow, which will affect the overall performance of the centrifugal fan. In order to improve the performance of the fan, there are researches on volute optimization at home and abroad at present. The document "Optimization Design of Volute of Centrifugal Compressor" (Gas Turbine Technology) mentions a method of changing the cross-sectional shape of the volute, the document "Improvement and Test of Volute Profile of Centrifugal Fan" (Fluid Machinery) proposes a new method of designing the volute profile, and the document "Centrifugal Ventilator" mentions a method of adding anti-vortex ring. The adoption of these methods has played a very good role in improving the performance and efficiency of the centrifugal fan. But the overall efficiency of the centrifugal fan is generally 50%~80%, mostly lower than 60%, generally low.

[0003] The volute of the traditional centrifugal fan is formed by welding or engaging the left and right side plates of the shell with the volute plate (see Figure 5 、 Figure 6 ), the specific structure is that two volute side plates 1 and a volute plate 2 welded between the two volute side plates 1, one of the volute side plates 1 is provided with an air inlet 3, and the two volute side plates 1 and the volute plate 2 form an air outlet 4 at one end, the volute is designed as an equal-width rectangular cross section, which can not only facilitate manufacturing, but also reduce manufacturing errors, but when the airflow flows in the volute, strong vortex will be generated at the right angle where the volute side plate 1 and the volute plate 2 meet, which does not meet the structural requirements of fluid mechanics, and will cause the temperature of the airflow in the shell to rise and reduce the efficiency of the fan.

[0004] Therefore, it is necessary to design a volute mechanism of centrifugal fan to improve the above problems. CONTENT OF THE UTILITY MODEL

[0005] In view of the defects of the prior art, the purpose of the utility model is to provide a volute mechanism of centrifugal fan, which makes the airflow flow smoothly in the volute by the arc structure of the two ends of the volute plate connected with the volute side plate, avoids vortex, and generates the maximum kinetic energy, thereby improving the efficiency of the fan.

[0006] In order to achieve the above purpose, the utility model provides the following technical scheme:

[0007] A centrifugal fan volute mechanism includes two sets of parallel volute side plates and a volute plate welded and fixed between the two sets of volute side plates near the outer end. The two ends of the volute plate connected to the volute side plates are both arc-shaped structures.

[0008] As a preferred embodiment of this utility model, the radius of the arc-shaped structure is not less than 15mm.

[0009] As a preferred embodiment of this utility model, the arc-shaped structures at both ends of the worm plate are 45° arc angles, and the end of the worm shell side plate connected to the worm plate is also a 45° arc angle. The 45° arc angle of the worm plate and the 45° arc angle of the worm shell side plate are welded and fixed accordingly.

[0010] As a preferred embodiment of this utility model, the volute plate includes a straight plate and arc plates disposed on both sides of the straight plate. The straight plate is welded and fixed to the arc plates on both sides, and the arc plates are welded and fixed to the corresponding volute side plates.

[0011] As a preferred embodiment of this utility model, the overall cross-section of the worm gear is semi-circular.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] This invention features a circular arc structure at both ends of the connection between the volute plate and the volute side plate, allowing airflow to flow smoothly within the volute and avoiding eddies. This maximizes kinetic energy and improves the efficiency of the fan. Under the same operating conditions, air pressure, and air volume, the fan outlet temperature is significantly reduced, and the motor current is reduced by 10%-15%, resulting in significant energy savings. Attached Figure Description

[0014] Figure 1 This is a side sectional view of the volute side plate and volute plate of the volute mechanism of a centrifugal fan.

[0015] Figure 2 This is a side cross-sectional view of the volute side plate and volute plate of the second embodiment of the volute mechanism of a centrifugal fan.

[0016] Figure 3 This is a side cross-sectional view of the volute side plate and volute plate of the third embodiment of the volute mechanism of a centrifugal fan.

[0017] Figure 4 A side cross-sectional view of the volute side plate and volute plate of the fourth embodiment of the volute mechanism of a centrifugal fan.

[0018] Figure 5 This is a schematic diagram of the volute mechanism of a centrifugal fan in the prior art;

[0019] Figure 6 This is a side view sectional view of the volute side plate and volute plate in the prior art.

[0020] In the diagram: 1. Cutter shaft; 2. Blade; 3. Protective cover body; 31. Upper protective cover; 311. Movable joint; 312. First through hole; 313. First outer edge connecting piece; 314. Connecting hole; 32. Lower protective cover; 321. Second through hole; 322. Second outer edge connecting piece; 33. Upper bushing; 331. Receiving cavity; 332. Limiting strip; 34. Lower bushing; 35. Connecting screw assembly; 351. Hex socket head cap screw; 352. Hex socket head cap screw; 36. Wing screw. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model. Example 1

[0022] Please see Figure 1 This embodiment provides a volute mechanism for a centrifugal fan, including two sets of parallel volute side plates 1 and a volute plate 2 welded and fixed between the two sets of volute side plates 1 near the outer end. The two ends of the volute plate 2 connected to the volute side plates 1 are both arc-shaped structures with a radius of not less than 15mm, preferably 20-30mm, so that the airflow can flow smoothly in the volute, avoiding eddies, and generating maximum kinetic energy, thereby improving the efficiency of the fan. Under the same operating conditions and wind pressure and air volume, the fan outlet temperature is greatly reduced, and the motor current is reduced by 10%-15%, resulting in significant energy saving. Example 2

[0023] This embodiment provides a volute mechanism for a centrifugal fan, which is basically the same as in Embodiment 1. Please refer to Embodiment 1. Figure 2 The difference lies in the fact that the arc-shaped structures at both ends of the worm plate 2 are 45° arc angles, and the end where the worm shell side plate 1 connects to the worm plate 2 is also a 45° arc angle. The 45° arc angle of the worm plate 2 and the 45° arc angle of the worm shell side plate 1 are welded and fixed accordingly, so that after the 45° arc angle of the worm shell side plate 1 and the 45° arc angle of the worm plate 2 are butt-welded, they form the same arc-shaped structure of the worm plate 2 as in Embodiment 1. The difference is that the arc-shaped structure in Embodiment 1 is formed entirely by bending the end of the worm plate 2, while in this embodiment, the connecting ends of the worm plate 2 and the worm shell side plate 1 are bent to a certain extent. The advantage is that it takes into account the factors of material mechanics and manufacturing process, in order to facilitate manufacturing. Example 3

[0024] This embodiment provides a volute mechanism for a centrifugal fan, which is basically the same as in Embodiment 1. Please refer to Embodiment 1. Figure 3 The difference lies in that: the volute 2 includes a straight plate 21 and arc plates 22 disposed on both sides of the straight plate 21. The straight plate 21 is welded and fixed to the arc plates 22 on both sides, and the arc plates 22 are welded and fixed to the corresponding volute side plates 1. Compared with embodiment 1, by dividing the volute 2 into three parts, namely a straight plate 21 and two arc plates 22, and welding them together, the manufacturing difficulty is reduced, and the connection between the volute 2 and the volute side plates 1 is a smooth arc transition, with no dead angles, which meets the structural requirements of fluid mechanics, avoids the generation of eddies, and improves the efficiency of the fan. Example 4

[0025] This embodiment provides a volute mechanism for a centrifugal fan, which is basically the same as in Embodiment 1. Please refer to Embodiment 1. Figure 4 The difference lies in that the overall cross-section of the worm plate 2 is semi-circular, and its manufacturing process is not exactly the same as that of Example 1. Example 1 is an integrated structure with a straight plate and a rounded arc in the middle. In this example, the worm plate 2 is an overall rounded arc structure, which ensures that the connection between the worm plate 2 and the worm shell side plate 1 is a rounded arc structure, thus reducing the manufacturing difficulty in the processing technology.

[0026] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this technical solution are within the protection scope of this utility model.

Claims

1. A centrifugal fan casing mechanism, comprising two sets of parallel casing side plates (1) and a volute plate (2) welded and fixed between the two sets of casing side plates (1) near the outer end, characterized in that: Both ends of the volute plate (2) that connect to the volute side plate (1) are arc-shaped structures.

2. The volute mechanism of a centrifugal fan according to claim 1, characterized in that: The radius of the arc-shaped structure is not less than 15mm.

3. The volute mechanism of a centrifugal fan according to claim 2, characterized in that: The arc-shaped structures at both ends of the worm plate (2) are 45° arc angles. The end of the worm shell side plate (1) connected to the worm plate (2) is also 45° arc angle. The 45° arc angle of the worm plate (2) and the 45° arc angle of the worm shell side plate (1) are welded and fixed accordingly.

4. The volute mechanism of a centrifugal fan according to claim 2, characterized in that: The volute plate (2) includes a straight plate (21) and arc plates (22) disposed on both sides of the straight plate (21). The straight plate (21) is welded and fixed to the arc plates (22) on both sides, and the arc plates (22) are welded and fixed to the corresponding volute side plates (1).

5. The volute mechanism of a centrifugal fan according to claim 2, characterized in that: The overall cross-section of the worm plate (2) is semi-circular.

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