A sound absorption and noise reduction device for large vertical motors

Abstract

The present invention relates to a sound absorption and noise reduction device for a large vertical motor, and relates to the technical field of overall noise reduction for motors. The device comprises a first stator base sound absorption portion arranged symmetrically on the sides of the cooling air duct, and a second stator base sound absorption portion arranged at the four corners of the motor base. The first stator base sound absorption portion comprises a damping material, a stainless steel microporous plate, and a baffle arranged in sequence; the second stator base sound absorption portion comprises a damping material, sound-absorbing cotton, a stainless steel microporous plate, and a baffle arranged in sequence. The present invention symmetrically arranges multiple sound-absorbing materials with different functions at specific locations within the motor cavity, directly facing the internal noise source of the rotating motor, effectively absorbing sound energy and suppressing the transmission of sound waves, thereby preventing or effectively reducing the transmission of sound waves within the motor, thereby reducing noise and significantly reducing motor operating noise.

Description

Technical Field

[0001] The present invention relates to the technical field of overall noise reduction of motors, and in particular to a sound absorption and noise reduction device for large vertical motors. The device adopts advanced structures and materials to absorb sound inside large vertical motors to significantly reduce noise. The present invention can also be applied to various large or extra-large rotating motors with high requirements for operating noise. Background Art

[0002] At present, the noise requirements of some medium- and high-speed large vertical motors (mainly suitable for the main motors of large pumping stations) generally do not exceed 85dB. Under normal circumstances, by adopting appropriate electromagnetic schemes and structures: or improving the processing and assembly accuracy of motor parts: or setting sound-absorbing materials on the outside of the motor (upper and lower wind tunnel covers) and other methods or measures, the noise of the motor during rated operation can be better controlled to around 85dB. However, with the annual increase in key operating indicators such as the noise of large motors (some medium- and high-speed large vertical motors require that their noise during rated operation is no higher than 80dB, or even no higher than 75dB), the above series of methods or measures can no longer meet this higher requirement. In particular, for high-power motors with large air volume, high wind speed, a large proportion of ventilation noise and extremely high noise requirements, the noise reduction effect achieved by the above noise reduction methods or measures is already very limited.

[0003] Noise from large motors primarily stems from internal electromagnetic fields and ventilation. Therefore, applying sound absorption treatment to the motor's interior directly addresses the noise source and effectively addresses the aforementioned low-noise requirement. However, due to the complex structure of the motor's frame, which is a crucial component of the symmetrical cooling duct and bears the most critical load, achieving noise reduction through sound absorption treatment is challenging. This is the fundamental reason why internal sound absorption treatment for these motors is currently unavailable in the industry.

[0004] Due to the structural complexity of large vertical motors, noise reduction within such motors faces a variety of technical challenges, including the following:

[0005] 1. Considering that most of the sound-absorbing materials are installed inside the motor, the sound-absorbing materials must have the characteristics of high temperature resistance, non-magnetic conductivity, easy installation, and not easy to age;

[0006] 2. Considering the complexity of the stator frame's internal structure and the fact that it faces the noise source directly, it is necessary to reduce the internal reverberation sound. On the other hand, due to the complexity of the structure, the shape of the sound-absorbing material needs to be plastic to better match its internal structure;

[0007] 3. The stator frame is the core of the entire motor's force transmission and force bearing, and it is necessary to focus on reducing its surface vibration and reducing wall radiation noise;

[0008] 4. The stator frame should have assembly holes, and the sound absorption treatment after the holes are opened needs to be considered;

[0009] 5. The motor requires a large amount of cooling air, and the position of the sound-absorbing material arranged in the motor cavity cannot cause adverse effects on the ventilation of the motor (especially between the stator frame and the iron core);

[0010] 6. The motor has high power and needs to be equipped with an air-water cooler. The opening of the cooler is an important channel for noise transmission, and the sound of water flow in the cooler is also one of the sources of noise, so it needs to be treated with sound absorption.

[0011] 7. Since the wind deflector directly faces the sound source, it is not easy to install sound-absorbing materials due to the structure of the wind deflector. It is necessary to use a deflector with good overall rigidity, good flow conduction and good vibration absorption effect;

[0012] 8. The upper frame is located above the stator and rotor, and assembly holes need to be opened, and the sound absorption treatment needs to be considered as a whole;

[0013] 9. The lower frame is located below the stator and rotor, and assembly holes need to be opened, and its sound absorption treatment needs to be considered as a whole. Summary of the Invention

[0014] The purpose of the present invention is: based on the above background, by adaptively designing the machine base, cooler cavity, upper frame, lower frame (bearing bracket) and arranging different sound-absorbing materials, a sound absorption and noise reduction device is proposed inside a large vertical motor to significantly reduce the operating noise of the motor.

[0015] In order to achieve the above-mentioned objectives, the technical solution of the present invention provides a sound absorption and noise reduction device for a large vertical motor, comprising a first stator base sound absorption portion arranged on the side of a symmetrical cooling air duct, and a second stator base sound absorption portion arranged at the four corners of the base; the first stator base sound absorption portion comprises a damping material, a stainless steel microporous plate, and a baffle arranged in sequence; the second stator base sound absorption portion comprises a damping material, sound-absorbing cotton, a stainless steel microporous plate, and a baffle arranged in sequence.

[0016] Preferably, it also includes a cooler sound-absorbing structure arranged around the inner surface of the cooler shell, which includes sound-absorbing cotton arranged on the inner surface of the cooler shell, and a mesh plate arranged on the side of the sound-absorbing cotton close to the cooler.

[0017] Preferably, it also includes an upper frame sound-absorbing cover plate provided at the upper frame assembly hole, a lower frame sound-absorbing cover plate provided at the lower frame assembly hole, and a base sound-absorbing cover plate provided at the stator base assembly hole, and the upper frame sound-absorbing cover plate, the lower frame sound-absorbing cover plate and the base sound-absorbing cover plate all include a cover plate, sound-absorbing cotton provided on one side of the cover plate, and a mesh plate provided on the side of the sound-absorbing cotton away from the cover plate.

[0018] Preferably, the damping material can be adhered to the inner surface of the cover plate of the base by glue.

[0019] Preferably, the damping material is a flexible damping patch that is temperature-resistant up to 180° C. and easily shaped.

[0020] Preferably, the thickness of the damping patch is in the range of 5 to 10 mm.

[0021] Preferably, the sound-absorbing cotton is made of sound-absorbing fiber cotton that can withstand temperatures up to 180°C.

[0022] Preferably, the thickness of the sound-absorbing cotton ranges from 50 to 400 mm.

[0023] Preferably, it also includes an upper air induction plate and a lower air induction plate located above and below the stator and the rotor.

[0024] Preferably, the upper air induction plate and the lower air induction plate are both made of precision cast aluminum structure.

[0025] In summary, the present invention has the following beneficial technical effects:

[0026] 1. The present invention is simple to implement and operate. By symmetrically arranging a variety of sound-absorbing materials with different functions at specific locations within the motor cavity, the material directly faces the internal noise source of the rotating motor, effectively absorbs sound energy, and suppresses the transmission of sound waves. This prevents or effectively reduces the transmission of sound waves within the motor, thereby reducing noise and significantly reducing motor operating noise.

[0027] 2. The stainless steel microporous plate in the present invention is fixed to the motor base by welding, which is firm and reliable, and forms a certain arc surface at the four corners of the motor base, which reduces the dead wind area, can effectively improve the ventilation performance of the motor, reduce the temperature rise of the motor, and increase the life of the motor;

[0028] 3. The present invention also has a good improvement effect on other motors with excessive internal mechanical noise (especially motors with high speed and large wind noise). Without affecting the appearance and overall performance of the motor, the present invention can significantly reduce the noise of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a general layout diagram of the first sound absorption treatment of a large vertical motor sound absorption and noise reduction device of the present invention;

[0030] Figure 2 This is a general layout diagram of the second sound absorption treatment of a large vertical motor sound absorption and noise reduction device of the present invention;

[0031] Figure 3 This is a general layout diagram of the third sound absorption treatment of a large vertical motor sound absorption and noise reduction device of the present invention;

[0032] Figure 4This is a schematic diagram of the structure of an upper frame sound-absorbing cover, a lower frame sound-absorbing cover or a base sound-absorbing cover in a sound-absorbing and noise-reducing device for a large vertical motor according to the present invention;

[0033] Figure 5 This is a schematic structural diagram of a cooler sound absorption structure in a large vertical motor sound absorption and noise reduction device according to the present invention;

[0034] Figure 6 This is a schematic structural diagram of the first base sound absorption part of a large vertical motor sound absorption and noise reduction device according to the present invention;

[0035] Figure 7 This is a schematic structural diagram of the second base sound absorption part of a large vertical motor sound absorption and noise reduction device according to the present invention;

[0036] Figure 8 This is a schematic diagram of the sound absorption structure at the four corners of the machine base in a large vertical motor sound absorption and noise reduction device of the present invention, which is used to show that stainless steel microporous plates need to be cut into different shapes.

[0037] Figure numerals: 1. upper frame; 2. upper frame sound-absorbing cover; 3. upper air induced draft plate; 4. stator; 5. rotor; 6. cooler; 7. cooler sound-absorbing part; 8. lower air induced draft plate; 9. lower frame; 10. lower frame sound-absorbing cover; 11. first stator base sound-absorbing part; 12. second stator base sound-absorbing part; 13. base sound-absorbing cover; 14. cover; 15. sound-absorbing cotton; 16. mesh plate; 17. damping material; 18. stainless steel microporous plate; 19. baffle. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] The present invention discloses a sound absorption and noise reduction device for a large vertical motor. The device is installed within the motor's interior. The device comprises a cover plate sound absorption structure, a cooler sound absorption structure, and a base sound absorption structure. The interior of the motor is defined as follows: between the inner wall of the stator base and the stator 4 core and coils; between the outer surface of the air cooler 6 body and the inner wall of the air cooler 6 shell; between the lower portion of the upper frame 1 and the stator 4 and rotor 5; and between the upper portion of the lower frame 9 and the stator 4 and rotor 5.

[0040] The cover plate sound-absorbing structure includes an upper frame sound-absorbing cover plate 2 provided at the assembly opening of the upper frame 1, a lower frame sound-absorbing cover plate 10 provided at the assembly opening of the lower frame 9, and a stator base sound-absorbing cover plate 13 provided at the assembly opening of the stator base. Each of the upper frame sound-absorbing cover plate 2, the lower frame sound-absorbing cover plate 10, and the base sound-absorbing cover plate 13 includes a cover plate 14, sound-absorbing cotton 15 provided on one side of the cover plate 14, and a mesh plate 16 provided on the side of the sound-absorbing cotton 15 away from the cover plate 14. The upper frame sound-absorbing cover plate 2, the lower frame sound-absorbing cover plate 10, and the base sound-absorbing cover plate 13 are primarily used for sound absorption after the assembly openings. The sound-absorbing cotton 15 must face the interior of the motor and must be firmly and reliably fixed to prevent it from falling off.

[0041] The cooler sound absorbing part 7 of the cooler sound absorbing structure is arranged around the inner surface of the cooler shell 6, mainly including the radial surface, upper surface and lower surface of the cooler 6. Its sound absorbing structure is mainly composed of sound absorbing cotton 15 arranged on the inner surface of the cooler shell 6, and a mesh plate 16 arranged on the side of the sound absorbing cotton 15 close to the cooler 6.

[0042] The sound absorption structure of the machine base includes a first stator base sound absorption part 11 mainly arranged on the two main sides of the symmetrical cooling air duct, and a second stator base sound absorption part 12 mainly arranged at the four corners of the machine base; the first stator base sound absorption part 11 is composed of a damping material 17, a stainless steel microporous plate 18, and a baffle 19 arranged in sequence. Figure 6 The second stator frame sound absorbing portion 12 is sequentially arranged by the damping material 17, the sound absorbing cotton 15, the stainless steel microporous plate 18, and the baffle 19, see Figure 7 Due to the complex structure of the base, the stainless steel microporous plate 18 needs to be cut into different shapes to adapt to the structure of the base, see Figure 8 .

[0043] The main technical features of the present invention are:

[0044] (1) Selection of key sound-absorbing materials:

[0045] ① Damping material 17 is used to reduce vibration on the machine base surface and reduce wall-radiated noise. It uses a flexible, easily shaped damping patch with a temperature resistance of over 180°C. Because it is a non-metallic material, it can be fixed with a two-component high-strength adhesive. The thickness of the flexible patch is 5-10mm.

[0046] ② Sound-absorbing cotton 15 is used to reduce internal reverberation. It uses special sound-absorbing fiber cotton, which is non-flammable and can withstand temperatures up to 180°C.

[0047] ③ The stainless steel microporous plate 18 is mainly used to fix the sound absorbing material and can be welded to the machine base by argon arc welding or other methods.

[0048] ④ Upper and lower air induction plates 3 and 8 are provided above and below the stator 4 and the rotor 5, respectively, and both are made of precision cast aluminum structure with good sound absorption.

[0049] (2) Overall layout considerations:

[0050] ① The stator frame is composed of multiple layers of ring plates, support tubes, and support ribs to form the frame wall, and the outer shell (including the cooler shell) has a large sound receiving surface, which is the key to overall noise reduction. Different combinations of sound-absorbing materials are used in different positions and spaces of the stator frame; this arrangement can effectively absorb sound in all cylindrical directions of the motor.

[0051] ② In addition to considering the steel plate thickness required for load-bearing, the upper frame 1 and the lower frame 9 also need to consider the impact of thickness on noise transmission, and appropriately increase the steel plate thickness near the noise source. This arrangement can effectively absorb sound at both end faces of the motor.

[0052] ③ The stator 4, upper frame 1, and lower frame 9 need to have multiple assembly openings, which can be sealed with a base sound-absorbing cover 13. This arrangement can effectively absorb sound at the local assembly openings of the motor.

[0053] (3) Assembly or fixation of main parts:

[0054] ① The damping material 17 (damping patch) can be pasted to the inner surface of the cover plate of the machine base with special glue (the pasting position includes the two sides of the symmetrical two-way ventilation of the machine base and the four corner cover plates of the machine base). It needs to be placed for more than 24 hours to ensure that it is firmly pasted before the next step can be carried out.

[0055] ② Place sound-absorbing cotton 15 on the four corner covers of the machine base, and then place stainless steel microporous plates 18 of different shapes on the two sides of the two-way ventilation and the four corner covers of the machine base. It is necessary to spot weld the stainless steel microporous plates 18 on the machine base to fix them, and then spot weld the baffles 19 to the machine base to constrain the curved plates.

[0056] ③ Composition of the machine base sound-absorbing cover plate 13: A sufficient amount of sound-absorbing cotton 15 is placed on the cover plate 14, and the mesh plate 16 is welded into a rectangular parallelepiped suitable for the size of the cover plate 14 according to the different sizes of each cover plate 14. The sound-absorbing cotton 15 is placed in the perforated plate, and the mesh plate 16 is welded and fixed to the cover plate 14.

[0057] The present invention designs the motor cavity and optimizes sound absorption based on the location of components relative to the noise source, including the selection, fixation, and thickness of sound-absorbing materials. The sound absorption treatment of the inner wall of the stator frame is a key focus, with the following specific features:

[0058] 1. Octagonal stator frame sound absorption structure: The scope of fixing the sound absorption material mainly includes most of the radiation surface (cylindrical surface) of the frame, including the four corners and four planes of the frame;

[0059] 2. The stator frame sound absorption material is mainly composed of flexible damping patches, sound-absorbing cotton 15, and stainless steel microporous plates 18;

[0060] 3. The damping sheet (flexible damping patch) is made of high molecular polymer, which is resistant to high temperatures and easy to stick; the sound-absorbing cotton 15 is made of polyester fiber material, which is resistant to high temperatures; the stainless steel microporous plate 18 is made of 304 stainless steel plate, which is resistant to high temperatures, easy to install, and non-magnetic;

[0061] 4. The flexible damping patch adopts 5-10mm specifications, the sound-absorbing cotton 15 does not need to adopt 50-400mm specifications according to the installation location, and the 304 microporous plate adopts 1mm-2mm specifications and is welded into a cuboid or irregular shape;

[0062] 5. Arrangement order of sound-absorbing materials: Damping material 17 is glued to the inner surface of the machine base with special glue; sound-absorbing cotton 15 is placed on the damping material 17; 304 microporous plate is welded to the machine base.

[0063] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A large vertical motor sound absorption and noise reduction device, characterized by: The invention comprises a first stator base sound absorbing portion (11) arranged on the side of a symmetrical cooling air duct, and a second stator base sound absorbing portion (12) arranged at the four corners of the base; the first stator base sound absorbing portion (11) comprises a damping material (17), a stainless steel microporous plate (18), and a baffle (19) arranged in sequence; the second stator base sound absorbing portion (12) comprises a damping material (17), sound absorbing cotton (15), a stainless steel microporous plate (18), and a baffle (19) arranged in sequence; It also includes a cooler sound absorption structure arranged around the inner surface of the cooler (6) shell, which includes sound absorption cotton (15) arranged on the inner surface of the cooler (6) shell, and a mesh plate (16) arranged on the side of the sound absorption cotton (15) close to the cooler (6); It also includes an upper frame sound-absorbing cover plate (2) provided at an assembly opening of the upper frame (1), a lower frame sound-absorbing cover plate (10) provided at an assembly opening of the lower frame (9), and a base sound-absorbing cover plate (13) provided at an assembly opening of the stator base, wherein the upper frame sound-absorbing cover plate (2), the lower frame sound-absorbing cover plate (10), and the base sound-absorbing cover plate (13) all include a cover plate, sound-absorbing cotton (15) provided at one side of the cover plate, and a mesh plate (16) provided at a side of the sound-absorbing cotton (15) away from the cover plate. The damping material (17) can be glued to the inner surface of the cover plate of the machine base. The damping material (17) adopts a flexible damping patch that is heat-resistant up to 180°C and easy to shape. The thickness of the damping patch ranges from 5 to 10 mm. The sound-absorbing cotton (15) adopts sound-absorbing fiber cotton that is heat-resistant up to 180°C. The thickness of the sound-absorbing cotton (15) ranges from 50 to 400 mm. It also includes an upper air induction plate (3) and a lower air induction plate (8) located above and below the stator (4) and the rotor (5).

2. A large vertical motor sound absorption and noise reduction device according to claim 1, characterized in that: The upper air induction plate (3) and the lower air induction plate (8) both adopt a precision cast aluminum structure.

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