A noise reduction structure of a centrifugal fan

Abstract

This application discloses a noise reduction structure for a centrifugal fan, relating to the field of centrifugal fan technology. It includes a housing and a centrifugal impeller. The housing has an inlet and an outlet at both ends. Noise reduction components are installed inside the housing. The housing includes an upper shell and a lower shell. This application utilizes the cooperative arrangement of structures such as arc-shaped sound-absorbing cotton, a rotating rod, and abutment blocks. In use, the arc-shaped sound-absorbing cotton is attached to the side walls of the upper and lower volutes. The rotating rod is rotated to make the abutment block contact the arc-shaped sound-absorbing cotton. Then, the rotating rod is locked using a fixing component to secure the arc-shaped sound-absorbing cotton. The centrifugal impeller is then started. As the gas passes between the upper and lower volutes, the arc-shaped sound-absorbing cotton reduces the noise from the gas impacting the inner walls of the upper and lower volutes. This minimizes the noise increase caused by the airflow impacting the duct wall due to inertia at sharp bends when the gas enters the volute from the high-speed impeller, resulting in eddies and secondary flows.

Description

Technical Field

[0001] This application relates to the field of centrifugal fan technology, and in particular to a noise reduction structure for centrifugal fans. Background Technology

[0002] Centrifugal fans currently used in residential central air conditioning systems convert mechanical energy into the kinetic and pressure energy of gas through a high-speed rotating impeller. They consist of an impeller, volute, inlet and outlet, motor, bearings, and support. During operation, gas enters the impeller center axially from the fan. The impeller blades drive the gas to rotate at high speed. Under the action of centrifugal force, the gas is thrown towards the outer edge of the impeller, significantly increasing its kinetic energy and pressure. The high-speed gas enters the volute-shaped channel, where its speed decreases, and its kinetic energy is further converted into static pressure energy. The high-pressure gas is discharged through the outlet, completing the transportation or pressurization process.

[0003] However, the internal air duct of existing residential central air conditioning centrifugal fans is prone to noise increase during operation due to the small turning radius inside the volute. At the same time, when the gas enters the volute from the high-speed impeller, the airflow impacts the duct wall at sharp bends due to inertia, generating eddies and secondary flows. Utility Model Content

[0004] The purpose of this invention is to solve or at least alleviate the problem that the internal air duct of the centrifugal fan in existing household central air conditioning systems is prone to noise increase during operation due to the small turning radius inside the volute and the inertial impact of the airflow on the duct wall at sharp bends when the gas enters the volute from the high-speed impeller, generating eddies and secondary flows.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A noise reduction structure for a centrifugal fan includes a housing and a centrifugal impeller. The housing has an air inlet and an air outlet at both ends. A noise reduction assembly for reducing noise is provided inside the housing. The housing includes an upper shell and a lower shell. The noise reduction assembly includes an upper volute fixedly connected to one side wall of the upper shell. The centrifugal impeller is installed on one side wall of the upper shell and located inside the upper volute. A lower volute adapted to the upper volute is installed on one side wall of the lower shell. The inner side walls of the upper and lower volutes are provided with the same arc-shaped sound-absorbing cotton. Multiple rotating rods are rotatably connected to one side wall of the upper shell. The rotating rods are all located on one side of the arc-shaped sound-absorbing cotton and arranged in a circular array. Each rotating rod has a fixed abutment block on one side wall for abutting the arc-shaped sound-absorbing cotton against the side walls of the upper and lower volutes. A fixing assembly is provided on the upper shell to prevent the rotating rods from rotating.

[0006] By adopting the above technical solution, during use, the user connects the upper and lower shells to form a housing, connecting the upper and lower volutes. The arc-shaped sound-absorbing cotton is then fitted to the side walls of the upper and lower volutes. The rotating rod is then rotated to make the abutment block rotate, abutting against the arc-shaped sound-absorbing cotton. The rotating rod is then locked by a fixing component to prevent rotation, thus securing the arc-shaped sound-absorbing cotton. The centrifugal impeller is then activated, allowing gas to enter the housing through the air inlet. As the gas passes between the upper and lower volutes, the arc-shaped sound-absorbing cotton reduces the noise from the gas impacting the inner walls of the upper and lower volutes. This minimizes the noise increase caused by the airflow impacting the duct wall due to inertia at sharp bends when the gas enters the volute from the high-speed impeller.

[0007] Optionally, the fixing assembly includes a plurality of first elastic plates fixedly connected to one side wall of the upper shell. Each side wall of the upper shell is provided with a connecting rod on one side of the first elastic plate. One end of the connecting rod passes through the upper shell and is fixedly connected to the rotating rod. The other end of the connecting rod is fixedly connected to a second elastic plate. A groove is opened on the upper surface of the second elastic plate, and the first elastic plate is sleeved in the groove.

[0008] By adopting the above technical solution, by rotating the connecting rod, the rotating rod is driven to rotate, so that when the abutting block abuts the arc-shaped sound-absorbing cotton against the upper and lower volutes, the second elastic plate approaches the first elastic plate. Then, by bending the second elastic plate, the groove is fitted onto the first elastic plate, preventing the arc-shaped sound-absorbing cotton from moving when the connecting rod rotates during use. At the same time, when the arc-shaped sound-absorbing cotton needs to be replaced, it is convenient to quickly disassemble the arc-shaped sound-absorbing cotton.

[0009] Optionally, a sponge layer is fixedly connected to the outer wall of the housing, and a foam layer is fixedly connected to the side wall of the sponge layer away from the housing.

[0010] By adopting the above technical solutions, the noise reduction effect of the shell can be improved through the sponge layer and foam layer, thereby reducing the noise during the operation of the centrifugal fan.

[0011] Optionally, a limiting plate for preventing the second elastic plate from disengaging is fixedly connected to the top of the first elastic plate.

[0012] By adopting the above technical solution, when the second elastic plate is placed on the first elastic plate, the limiting plate can be passed through the groove by bending the first elastic plate, and then the first elastic plate can be reset and fit against the side wall of the groove. This can block the second elastic plate and prevent the second elastic plate from detaching from the first elastic plate.

[0013] Optionally, the inner walls of both the upper and lower volutes are provided with anti-slip textures that are compatible with the arc-shaped sound-absorbing cotton.

[0014] By adopting the above technical solutions, the anti-slip texture can increase the friction between the arc-shaped sound-absorbing cotton and the upper and lower volutes, preventing the arc-shaped sound-absorbing cotton from slipping.

[0015] Optionally, a shock-absorbing pad is fixedly connected to one end of the lower volute near the upper volute.

[0016] By adopting the above technical solutions, the vibration of the centrifugal impeller can be reduced by using shock-absorbing pads when connecting the upper and lower volutes.

[0017] In summary, the beneficial effects of this application are as follows: 1. This application utilizes the coordinated arrangement of structures such as arc-shaped sound-absorbing cotton, rotating rod, and abutment block. During use, the user connects the upper and lower shells to form a housing, connecting the upper and lower volutes. The arc-shaped sound-absorbing cotton is then fitted against the side walls of the upper and lower volutes. The rotating rod is then rotated to rotate the abutment block, causing it to abut against the arc-shaped sound-absorbing cotton. The rotating rod is then locked by a fixing component to prevent rotation, thus securing the arc-shaped sound-absorbing cotton. The centrifugal impeller is then activated, allowing gas to enter the housing through the air inlet. As the gas passes between the upper and lower volutes, the arc-shaped sound-absorbing cotton reduces the noise from the gas impacting the inner walls of the upper and lower volutes. This minimizes the noise increase caused by the airflow impacting the duct wall at sharp bends when the gas enters the volute from the high-speed impeller, resulting in eddies and secondary flows. 2. By rotating the connecting rod, the rotating rod is driven to rotate, so that when the abutting block abuts the arc-shaped sound-absorbing cotton against the upper and lower volutes, the second elastic plate is close to the first elastic plate. Then, by bending the second elastic plate, the groove is fitted onto the first elastic plate, which prevents the arc-shaped sound-absorbing cotton from moving when the connecting rod rotates during use. At the same time, it facilitates quick and easy disassembly of the arc-shaped sound-absorbing cotton when it needs to be replaced. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the lower shell structure of this utility model; Figure 3 This is an enlarged schematic diagram of the upper shell structure of this utility model; Figure 4 For the present utility model Figure 3 Enlarged structural diagram of region A in the middle; Figure 5 For the present utility model Figure 1 Enlarged structural diagram of region B in the middle; Figure 6 For the present utility model Figure 1 A magnified structural diagram of region C in the middle.

[0019] Explanation of reference numerals in the attached drawings: 1. Shell; 111. Air inlet; 112. Air outlet; 113. Upper shell; 114. Lower shell; 2. Centrifugal impeller; 5. Upper volute; 6. Lower volute; 7. Arc-shaped sound-absorbing cotton; 8. Rotating rod; 9. Abutment block; 10. First elastic plate; 11. Connecting rod; 12. Second elastic plate; 13. Groove; 14. Sponge layer; 15. Foam layer; 16. Limiting plate; 17. Anti-slip texture; 18. Shock-absorbing pad. Detailed Implementation

[0020] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail.

[0021] Please see Figure 2-4 A noise reduction structure for a centrifugal fan includes a housing 1 and a centrifugal impeller 2. The housing 1 has an air inlet 111 and an air outlet 112 at both ends. Noise reduction components are installed inside the housing 1. The housing 1 includes an upper shell 113 and a lower shell 114. The noise reduction components include an upper volute 5, a lower volute 6, an arc-shaped sound-absorbing cotton 7, a rotating rod 8, and a contact block 9. An external rotor motor is installed on the inner side of one side of the centrifugal impeller 2. In this embodiment, the external rotor motor includes a rotor magnetic ring and a stator. The rotor magnetic ring is fixedly connected in a ring to the inner wall of one side of the centrifugal impeller 2, while the stator is movably connected to the inner wall of the rotor magnetic ring via a magnetic levitation air gap connection, with an air gap of 0.2-2 mm between the two. In this embodiment, the internal iron core of the stator can be a twelve-slot, ten-pole or twelve-slot, fourteen-pole structure.

[0022] The upper volute 5 is fixedly connected to one side wall of the upper shell 113. The centrifugal impeller 2 is installed on one side wall of the upper shell 113 and located inside the upper volute 5. The lower volute 6 is installed on one side wall of the lower shell 114 and is adapted to the upper volute 5. The arc-shaped sound-absorbing cotton 7 is provided on the inner side wall of the upper volute 5 and the lower volute 6. Multiple rotating rods 8 are provided and are all rotatably connected to one side wall of the upper shell 113. The rotating rods 8 are all located on one side of the arc-shaped sound-absorbing cotton 7 and are arranged in a ring array. Multiple abutment blocks 9 are provided and are fixedly connected to one side wall of the rotating rods 8 respectively, for abutting the arc-shaped sound-absorbing cotton 7 against the side walls of the upper volute 5 and the lower volute 6. The upper shell 113 is provided with a fixing component to prevent the rotating rods 8 from rotating.

[0023] In use, the user connects the upper shell 113 and the lower shell 114 to form the shell 1, connecting the upper volute 5 and the lower volute 6. The arc-shaped sound-absorbing cotton 7 is then attached to the side walls of the upper volute 5 and the lower volute 6. The rotating rod 8 is then rotated to make the abutment block 9 rotate, abutting the abutment block 9 against the arc-shaped sound-absorbing cotton 7. The rotating rod 8 is then locked by the fixing component to prevent rotation, and the arc-shaped sound-absorbing cotton 7 is fixedly installed. Then, by starting the centrifugal impeller 2, the gas enters the shell 1 from the air inlet 111. When passing between the upper volute 5 and the lower volute 6, the arc-shaped sound-absorbing cotton 7 reduces the noise from the gas impacting the inner walls of the upper volute 5 and the lower volute 6. This minimizes the problem of increased noise caused by the airflow impacting the duct wall due to inertia at sharp bends when the gas enters the volute from the high-speed impeller.

[0024] Reference Figure 1 , Figure 4 and Figure 5 The fixing assembly includes multiple first elastic plates 10 fixedly connected to one side wall of the upper shell 113. Each side wall of the upper shell 113 is provided with a connecting rod 11 on one side of the first elastic plate 10. One end of the connecting rod 11 passes through the upper shell 113 and is fixedly connected to the rotating rod 8. The other end of the connecting rod 11 is fixedly connected to a second elastic plate 12. The upper surface of the second elastic plate 12 is provided with a slot 13. The first elastic plate 10 is fitted into the slot 13. By rotating the connecting rod 11, the rotating rod 8 is driven to rotate, so that when the abutment block 9 abuts the arc-shaped sound-absorbing cotton 7 against the upper volute 5 and the lower volute 6, the second elastic plate 12 approaches the first elastic plate 10. Then, by bending the second elastic plate 12, the slot 13 is fitted onto the first elastic plate 10 to prevent the arc-shaped sound-absorbing cotton 7 from moving when the connecting rod 11 rotates during use. At the same time, it is convenient to quickly disassemble the arc-shaped sound-absorbing cotton 7 when it needs to be replaced.

[0025] Reference Figure 6 A sponge layer 14 is fixedly connected to the outer wall of the housing 1, and a foam layer 15 is fixedly connected to the side wall of the sponge layer 14 away from the housing 1. The sponge layer 14 and the foam layer 15 can improve the noise reduction effect of the housing 1 and reduce the noise when the centrifugal fan is working.

[0026] Reference Figure 5 The top end of the first elastic plate 10 is fixedly connected to a limiting plate 16 for preventing the second elastic plate 12 from detaching. When the second elastic plate 12 is put on the first elastic plate 10, the limiting plate 16 passes through the slot 13 by bending the first elastic plate 10. Then the first elastic plate 10 is reset and fits against the side wall of the slot 13, so that the limiting plate 16 can block the second elastic plate 12 and prevent the second elastic plate 12 from detaching from the first elastic plate 10.

[0027] Reference Figure 2The inner walls of the upper volute 5 and the lower volute 6 are provided with anti-slip textures 17 that are adapted to the arc-shaped sound-absorbing cotton 7. The anti-slip textures 17 can increase the friction between the arc-shaped sound-absorbing cotton 7 and the upper volute 5 and the lower volute 6, and prevent the arc-shaped sound-absorbing cotton 7 from sliding.

[0028] Reference Figure 2 A damping pad 18 is fixedly connected to one end of the lower volute 6 near the upper volute 5. When the upper volute 5 and the lower volute 6 are connected, the vibration of the centrifugal impeller 2 can be reduced by the damping pad 18.

[0029] The implementation principle of this application is as follows: In use, the user connects the upper shell 113 and the lower shell 114 to form the shell 1, connecting the upper volute 5 and the lower volute 6. The arc-shaped sound-absorbing cotton 7 is then attached to the side walls of the upper volute 5 and the lower volute 6. By rotating the connecting rod 11, the rotating rod 8 is driven to rotate, causing the abutment block 9 to abut the arc-shaped sound-absorbing cotton 7 against the inner walls of the upper volute 5 and the lower volute 6. At the same time, the second elastic plate 12 approaches the first elastic plate 10. Then, by bending the second elastic plate 12 and the first elastic plate 10, the limiting plate 16 passes through the slot 13. Then, the first elastic plate 10 returns to its original position and attaches to the side wall of the slot 13, causing the limiting plate 16 to block the second elastic plate 12. To prevent the second elastic plate 12 from detaching from the first elastic plate 10, the slot 13 is fitted onto the first elastic plate 10. This prevents the connecting rod 11 from rotating during use and secures the arc-shaped sound-absorbing cotton 7 in place. It also facilitates quick and easy disassembly of the arc-shaped sound-absorbing cotton 7 when it needs to be replaced. Then, by starting the centrifugal impeller 2, gas enters the housing 1 through the air inlet 111. As the gas passes between the upper volute 5 and the lower volute 6, the arc-shaped sound-absorbing cotton 7 reduces the noise from the gas impacting the inner walls of the upper volute 5 and the lower volute 6. This minimizes the noise increase caused by the airflow impacting the duct wall at sharp bends when the gas enters the volute from the high-speed impeller, resulting in vortices and secondary flows.

[0030] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A noise reduction structure for a centrifugal fan, comprising a housing (1) and a centrifugal impeller (2), wherein an air inlet (111) and an air outlet (112) are respectively provided at both ends of the housing (1), and a noise reduction component for reducing noise is provided inside the housing (1), wherein the housing (1) comprises an upper shell (113) and a lower shell (114), characterized in that: The noise reduction assembly includes an upper volute (5) fixedly connected to one side wall of the upper shell (113), a centrifugal impeller (2) installed on one side wall of the upper shell (113) and located inside the upper volute (5), a lower volute (6) adapted to the upper volute (5) installed on one side wall of the lower shell (114), the same arc-shaped sound-absorbing cotton (7) provided on the inner side wall of the upper volute (5) and the lower volute (6), a plurality of rotating rods (8) rotatably connected to one side wall of the upper shell (113), the rotating rods (8) are all located on one side of the arc-shaped sound-absorbing cotton (7) and arranged in a ring array, and a stop block (9) for abutting the arc-shaped sound-absorbing cotton (7) against the side wall of the upper volute (5) and the lower volute (6) is fixedly connected to one side wall of the rotating rods (8), and a fixing assembly for preventing the rotating rods (8) from rotating.

2. The noise reduction structure for a centrifugal fan according to claim 1, characterized in that: The fixing assembly includes multiple first elastic plates (10) fixedly connected to one side wall of the upper shell (113). Each side wall of the upper shell (113) is provided with a connecting rod (11) on one side of the first elastic plate (10). One end of the connecting rod (11) passes through the upper shell (113) and is fixedly connected to the rotating rod (8).

3. The noise reduction structure for a centrifugal fan according to claim 2, characterized in that: The other end of the connecting rod (11) is fixedly connected to a second elastic plate (12), and a groove (13) is opened on the upper surface of the second elastic plate (12), and the first elastic plate (10) is sleeved in the groove (13).

4. The noise reduction structure for a centrifugal fan according to claim 3, characterized in that: A sponge layer (14) is fixedly connected to the outer wall of the shell (1), and a foam layer (15) is fixedly connected to the side wall of the sponge layer (14) away from the shell (1).

5. The noise reduction structure for a centrifugal fan according to claim 4, characterized in that: The top end of the first elastic plate (10) is fixedly connected to a limiting plate (16) for preventing the second elastic plate (12) from disengaging.

6. The noise reduction structure for a centrifugal fan according to claim 5, characterized in that: The inner walls of both the upper volute (5) and the lower volute (6) are provided with anti-slip textures (17) that are compatible with the arc-shaped sound-absorbing cotton (7).

7. The noise reduction structure for a centrifugal fan according to claim 6, characterized in that: A shock-absorbing pad (18) is fixedly connected to one end of the lower volute (6) near the upper volute (5).

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