A volute-free centrifugal fan

Abstract

This utility model discloses a volute-less centrifugal fan, comprising: an impeller, the impeller including a front disc at the front, a middle disc at the rear, blades connecting the front disc and the middle disc, and a shaft disc fixed on the middle disc, the shaft disc being coaxially arranged with the middle disc; a frame, the frame being located outside the impeller, a panel on one side of the frame having an air inlet and an air inlet ring connected to its inner side, and support frames with bearing seats fixed on both the front and rear sides of the frame; a rotating shaft, the rotating shaft passing through the bearing seat and fixed through the shaft disc; and a drive device, the drive device being drively connected to the rotating shaft. The volute-less centrifugal fan designed in this utility model eliminates the volute, reducing airflow resistance and improving efficiency; the design of double belts and airfoil blades reduces noise; the reinforcing ring suppresses impeller deformation, resulting in vibration-free high-speed operation; and the tapered sleeve pulley allows for quick replacement and convenient maintenance.

Description

Technical Field

[0001] This utility model belongs to the field of fan development technology, specifically relating to a centrifugal fan without a volute. Background Technology

[0002] A volute-less centrifugal fan is a device that eliminates the traditional volute structure and directly utilizes the combination of an impeller and a housing to transport gas. Its design principle is based on centrifugal force and the aerodynamic characteristics of airfoil blades, improving efficiency and reducing noise by optimizing the impeller and airflow path. This technology was initially applied in air conditioning systems, the textile industry, and industrial drying equipment. In recent years, due to the demand for energy conservation and environmental protection, it has gradually expanded into fields such as biopharmaceuticals and precision manufacturing.

[0003] Currently, traditional volute centrifugal fans have the following drawbacks: (1) High energy loss: Vortexes are generated between the inner wall of the volute and the impeller, resulting in significant loss of airflow kinetic energy; (2) Noise pollution: The airflow collides multiple times within the volute, resulting in significant low- and mid-frequency noise; (3) Bulky size: The volute structure increases the overall weight of the equipment and limits the flexibility of installation; (4) Difficult maintenance: The volute obstructs the impeller, requiring complete disassembly and reassembly for maintenance, which is time-consuming and labor-intensive. Therefore, a volute-less centrifugal fan was designed to solve the above problems.

[0004] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this utility model and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this utility model. Utility Model Content

[0005] To overcome the shortcomings of the prior art, the purpose of this utility model is to provide a centrifugal fan without a volute.

[0006] To achieve the above and other related objectives, the technical solution provided by this utility model is: a centrifugal fan without a volute, comprising:

[0007] An impeller, comprising a front disc at the front, a middle disc at the rear, blades connecting the front disc and the middle disc, and a shaft disc fixed on the middle disc, wherein the shaft disc is coaxially arranged with the middle disc;

[0008] The frame is located outside the impeller. An air inlet is provided on a panel on one side of the frame and an air inlet ring is connected to its inner side. Support frames with bearing seats are fixed on the front and rear sides of the frame.

[0009] A rotating shaft passes through the bearing housing and is fixed by the shaft disc;

[0010] A drive unit is connected to the rotating shaft via a transmission mechanism. The drive unit is a motor, which can be a variable frequency permanent magnet motor to achieve stepless speed regulation.

[0011] Furthermore, the output shaft of the drive device is arranged parallel to the rotating shaft. One end of the rotating shaft is equipped with a driven pulley, and the output shaft of the drive device is equipped with a driving pulley. The driven pulley and the driving pulley are connected by a belt drive. In this design, both the driven pulley and the driving pulley are tapered sleeve pulleys, and the two pulleys are connected by two synchronous belts to achieve synchronous and stable movement of the output shaft and the rotating shaft.

[0012] Furthermore, the blades are provided with reinforcing rings, which include a first reinforcing ring and a second reinforcing ring. The first reinforcing ring is fixed to the inner side of the blade, and the second reinforcing ring is fixed to the outer side of the blade. In this design, the blades are evenly distributed in a ring shape between the front and middle discs. The reinforcing rings make the blades more secure, resulting in better overall impeller stability.

[0013] Furthermore, both the first and second reinforcing rings are annular stainless steel strips, laser-welded onto the blades. In this design, the reinforcing rings can suppress high-speed rotational deformation of the blades and extend the impeller's service life.

[0014] Furthermore, the blade has an airfoil curved surface structure, and the blade's installation angle is 25°~35°. In this design, the curved surface structure provides better airflow guidance and can reduce noise.

[0015] Furthermore, the air inlet ring has a conical structure with a taper of 30°~35°. In this design, the conical air inlet ring has a good airflow guiding effect.

[0016] Furthermore, a double-row angular contact ball bearing is installed within the bearing housing. In this design, the double-row bearing configuration can withstand bidirectional axial forces, thus improving stability.

[0017] Furthermore, the panel and the frame are connected by quick-release bolts. In this design, the quick-release structure facilitates the opening and maintenance of the panel.

[0018] Furthermore, the drive unit and the frame are mounted on the same base. In this design, the shared base for the drive unit and the frame facilitates the handling of the entire structure.

[0019] Furthermore, the base is provided with shock-absorbing pads. In this design, the shock-absorbing pads can isolate vibration transmission.

[0020] Due to the application of the above technical solution, the beneficial effects of this utility model compared with the prior art are as follows:

[0021] (1) Improved energy efficiency: The elimination of the volute reduces airflow resistance and improves efficiency.

[0022] (2) Significant noise reduction: The design of double belts and airfoil blades reduces noise.

[0023] (3) High rigidity: The reinforcing ring suppresses impeller deformation, and there is no vibration at high speed.

[0024] (4) Easy maintenance: The tapered sleeve pulley can be quickly replaced. Attached Figure Description

[0025] Figure 1 This is a schematic diagram (front view) of the overall structure of the fan of this utility model;

[0026] Figure 2 This is a schematic diagram of the overall structure of the fan of this utility model (rear view);

[0027] Figure 3 This is a schematic diagram of the impeller and related structures of this utility model;

[0028] In the above attached figures, 100 is the impeller; 101 is the front disc; 102 is the middle disc; 103 is the blade; 104 is the first reinforcing ring; 105 is the shaft disc; 106 is the second reinforcing ring; 200 is the frame; 201 is the panel; 202 is the air inlet ring; 203 is the bearing housing; 204 is the support frame; 300 is the rotating shaft; 401 is the driven wheel; 402 is the driving wheel; 500 is the drive unit; 600 is the belt; and 700 is the base. Detailed Implementation

[0029] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification.

[0030] It should be noted that in the description of this utility model, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. These terms are used only for the convenience of describing this utility model and for simplifying the description, 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. Furthermore, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance. The terms "horizontal," "vertical," and "suspended," etc., do not indicate that the component must be absolutely horizontal or suspended, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0033] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.

[0034] This embodiment provides a volute-less centrifugal fan; see appendix. Figure 1 Appendix Figure 2 and attached Figure 3 As shown, it includes:

[0035] Impeller 100 includes a front disc 101 at the front, a middle disc 102 at the rear, blades 103 connecting the front disc 101 and the middle disc 102, and a shaft disc 105 fixed on the middle disc 102. The shaft disc 105 is coaxially arranged with the middle disc 102. The diameter of impeller 100 is 250mm~1000mm. In specific embodiments, it can be 250mm, 280mm, 315mm, 355mm, 400mm, 450mm, 500mm, 560mm, 630mm, 710mm, 800mm, 900mm or 1000mm.

[0036] The frame 200 is located outside the impeller 100. The panel 201 on one side of the frame 200 has an air inlet and an air inlet ring 202 is connected to its inner side. The front and rear sides of the frame 200 are fixed with support frames 204 with bearing seats 203.

[0037] Rotating shaft 300 passes through bearing housing 203 and is fixed by shaft disc 105;

[0038] The drive unit 500 is connected to the rotating shaft 300 via a transmission. The drive unit 500 is a motor, which can be a variable frequency permanent magnet motor to achieve stepless speed regulation.

[0039] See appendix Figure 2 As shown, the output shaft of the drive device 500 is arranged parallel to the rotating shaft 300. One end of the rotating shaft 300 is equipped with a driven pulley 401, and the output shaft of the drive device 500 is equipped with a driving pulley 402. The driven pulley 401 and the driving pulley 402 are connected by a belt 600. Both the driven pulley 401 and the driving pulley 402 are tapered sleeve type belt pulleys 600, and the two belt pulleys 600 are connected by two synchronous belts 600 to achieve synchronous and stable movement of the output shaft and the rotating shaft 300.

[0040] See appendix Figure 3 As shown, the blade 103 is equipped with reinforcing rings, including a first reinforcing ring 104 and a second reinforcing ring 106. The first reinforcing ring 104 is fixed to the inner side of the blade 103, and the second reinforcing ring 106 is fixed to the outer side of the blade 103. The blades 103 are evenly distributed in a ring shape between the front disc 101 and the middle disc 102. The reinforcing rings can make the blades 103 more secure, resulting in better overall stability of the impeller 100. The first reinforcing ring 104 and the second reinforcing ring 106 are both annular stainless steel strips and are laser-welded to the blades 103. This can suppress high-speed rotational deformation of the blades 103 and extend the service life of the impeller 100.

[0041] The blade 103 has an airfoil curved surface structure, and the installation angle of the blade 103 is 25°~35°. The curved surface structure provides better airflow guidance and can reduce noise. The number of blades 103 is 10~30, and in specific embodiments, it can be 10, 20, 25, or 30 blades. The structure of the blade 103 includes, but is not limited to, an airfoil curved surface structure, and can also be a flat plate structure.

[0042] See appendix Figure 1 As shown, the air inlet ring 202 has a conical structure with a taper of 30° to 35°. The conical structure of the air inlet ring 202 provides good airflow guidance. The taper can be 30°, 32°, or 35°.

[0043] In some other embodiments, a double-row angular contact ball bearing is provided within the bearing housing 203. This allows it to withstand bidirectional axial forces, improving stability.

[0044] In some other embodiments, the panel 201 is connected to the frame 200 using quick-release bolts. This facilitates the opening and maintenance of the panel 201.

[0045] See appendix Figure 1 and attached Figure 2 As shown, the drive unit 500 and the frame 200 are mounted together on a base 700. This facilitates the handling of the entire structure. The base 700 is equipped with shock-absorbing pads. These pads isolate vibration transmission.

[0046] Example: Impeller 100 has a diameter of 500mm and is equipped with 22 NACA6412 airfoil blades 103; motor power is 7.5kW, which drives impeller 100 to 3600rpm through double 8M toothed belts; when the measured air volume is 6200m³ / h, the energy consumption is reduced by 28% compared with the volute fan, and the noise is 69dB.

[0047] The centrifugal fan designed in this utility model eliminates the volute, reducing airflow resistance and improving efficiency; the design of double belts and airfoil blades reduces noise; the reinforcing ring suppresses impeller deformation, resulting in vibration-free operation at high speeds; and the tapered pulley allows for quick replacement and convenient maintenance.

[0048] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it. They cannot be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be covered within the protection scope of this utility model.

Claims

1. A centrifugal fan without a volute, characterized in that, include: An impeller (100) includes a front disc (101) at the front, a middle disc (102) at the rear, blades (103) connecting the front disc (101) and the middle disc (102), and a shaft disc (105) fixed on the middle disc (102), the shaft disc (105) being coaxially arranged with the middle disc (102); The frame (200) is located outside the impeller (100). The panel (201) on one side of the frame (200) has an air inlet and an air inlet ring (202) is connected to its inner side. The front and rear sides of the frame (200) are fixed with support frames (204) with bearing seats (203). A rotating shaft (300) passes through the bearing housing (203) and is fixed by the shaft disc (105); A drive device (500) is connected to the rotating shaft (300) in a transmission manner.

2. The centrifugal fan without a volute according to claim 1, characterized in that: The output shaft of the drive device (500) is arranged parallel to the rotating shaft (300). One end of the rotating shaft (300) is equipped with a driven wheel (401), and the output shaft of the drive device (500) is equipped with a driving wheel (402). The driven wheel (401) and the driving wheel (402) are connected by a belt (600).

3. The centrifugal fan without a volute according to claim 1, characterized in that: The blade (103) is provided with a reinforcing ring, which includes a first reinforcing ring (104) and a second reinforcing ring (106). The first reinforcing ring (104) is fixed to the inner side of the blade (103), and the second reinforcing ring (106) is fixed to the outer side of the blade (103).

4. A centrifugal fan without a volute according to claim 3, characterized in that: Both the first reinforcing ring (104) and the second reinforcing ring (106) are annular stainless steel strips, which are laser-welded onto the blade (103).

5. A centrifugal fan without a volute according to claim 1, characterized in that: The blade (103) has an airfoil curved surface structure, and the installation angle of the blade (103) is 25°~35°.

6. A centrifugal fan without a volute according to claim 1, characterized in that: The air inlet ring (202) has a conical structure with a taper of 30°~35°.

7. A centrifugal fan without a volute according to claim 1, characterized in that: The bearing housing (203) is equipped with a double-row angular contact ball bearing.

8. A centrifugal fan without a volute according to claim 1, characterized in that: The panel (201) and the frame (200) are connected by quick-release bolts.

9. A centrifugal fan without a volute according to claim 1, characterized in that: The drive device (500) and the frame (200) are mounted together on a base (700).

10. A centrifugal fan without a volute according to claim 9, characterized in that: The base (700) is provided with shock-absorbing pads.

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