EP4663950A1

EP4663950A1 - Screw compressor

Info

Publication number: EP4663950A1
Application number: EP24756347.1A
Authority: EP
Inventors: Shengmei Yang; Kun Lin; Zhengxiang YU; Xiaokui MA
Original assignee: Tyco Fire and Security GmbH; Johnson Controls Air Conditioning and Refrigeration Wuxi Co Ltd
Current assignee: Tyco Fire and Security GmbH; Johnson Controls Air Conditioning and Refrigeration Wuxi Co Ltd
Priority date: 2023-02-16
Filing date: 2024-02-16
Publication date: 2025-12-17
Also published as: CN116085255B; TW202436759A; WO2024169977A1; CN116085255A

Abstract

The present application discloses a screw compressor, comprising: a shell, a pair of rotors, and a plurality of silencing devices. A plurality of resonant silencing devices is disposed on a rotor containing cavity inner wall, and each resonant silencing device is configured to have a preset inherent frequency, so as to absorb and attenuate pressure pulsation energy by forming resonance with sound waves having the preset inherent frequency, thereby reducing noise. In the screw compressor of the present application, the resonant silencing devices are disposed on the rotor containing cavity inner wall, such that the noise of the screw compressor can be eliminated more quickly and efficiently directly at the position where the gas pressure is highest and the position where the pressure pulsation is generated. Moreover, the resonant silencing devices of the present application can ensure that the resonant silencing devices will not affect the operation of the screw compressor by setting positions of a communication channel and an opening.

Description

Technical Field

The present application relates to the field of compressors, in particular to a screw compressor.

Background Art

A screw compressor comprises a pair of rotors; and rotor teeth of the pair of rotors are meshed with each other, causing changes in the volume of the element composed of the tooth-shaped space to complete the process of gas suction, compression, and discharge. Since the screw compressor forms discontinuous inter-tooth volumes through the meshing of the rotors, suction and exhaust cavities periodically communicate with a working cavity, causing unstable flow of gas, causing pressure pulsation during the suction and exhaust processes, and in turn causing vibration and noise of the compressor.

Summary of the Invention

The present application provides a screw compressor, comprising a shell, a pair of rotors, and a plurality of silencing devices. The shell comprises a rotor shell having a rotor containing cavity and a rotor containing cavity inner wall for defining the rotor containing cavity. The pair of rotors is disposed in the rotor containing cavity, wherein each rotor has rotor teeth, compression containing cavities are able to be formed between the rotor teeth of the pair of rotors and the rotor containing cavity inner wall, and the pair of rotors has a rotor suction inlet and a rotor exhaust outlet, wherein the pair of rotors is configured such that as the pair of rotors rotates, the compression containing cavities periodically generate volume changes, such that a gas in the compression containing cavities can move from the rotor suction inlet to the rotor exhaust outlet after being compressed and raised in gas pressure. The plurality of resonant silencing devices is disposed on the rotor containing cavity inner wall, and each resonant silencing device is configured to have a preset inherent frequency, so as to absorb and attenuate pressure pulsation energy by forming resonance with sound waves having the preset inherent frequency, thereby reducing noise.
According to the above content, the resonant silencing devices are an acoustic superstructure, wherein at least a part of the resonant silencing devices is configured to have different preset inherent frequencies.
According to the above content, the resonant silencing devices comprise a resonant cavity and at least one communication channel, and the at least one communication channel is in fluid communication with the resonant cavity, wherein each resonant silencing device is configured such that as the pair of rotors rotates, a pressure difference exists between the resonant cavity and the compression containing cavity outside the resonant silencing device, and the at least one communication channel can be in fluid communication with the resonant cavity and the compression containing cavity outside the resonant silencing device, such that a liquid in the compression containing cavity can enter the resonant cavity from the at least one communication channel or be discharged from the resonant cavity.
According to the above content, in an extending direction of the at least one communication channel, for the bottom of the at least one communication channel, one end thereof at least at the compression containing cavity is not higher than one end thereof in the resonant cavity, such that a liquid in the resonant cavity is discharged to the compression containing cavity through the at least one communication channel.
According to the above content, the rotor containing cavity inner wall comprises a front wall and a containing cavity wall, and the containing cavity wall is disposed around the resonant cavity, wherein for the bottom of the at least one communication channel, one end thereof in the resonant cavity is not higher than the containing cavity wall at the same location, such that the liquid in the resonant cavity can enter the at least one communication channel.
According to the above content, an inner surface of the bottom of the at least one communication channel is disposed tangentially to an inner surface of the containing cavity wall.
According to the above content, the rotor containing cavity inner wall further comprises a rear wall, the rear wall is disposed opposite to an inner surface of the front wall, the inner surface of the front wall of the rotor containing cavity inner wall is a partially spherical surface, and an inner surface of the rear wall is a smoothly curved surface.
According to the above content, an inner surface of the containing cavity wall of the resonant cavity is spherical.
According to the above content, the at least one communication channel comprises a first communication channel and a second communication channel, the resonant silencing device is configured such that as the pair of rotors rotates, the resonant cavity is first in fluid communication with a high-pressure compression containing cavity through the second communication channel, and is then in fluid communication with a low-pressure compression containing cavity through the first communication channel, so as to discharge the liquid in the resonant cavity.
According to the above content, the rotor teeth of the pair of rotors have tooth crests. The first communication channel and the second communication channel form a first opening and a second opening on the front wall, respectively. The first opening and the second opening of each resonant silencing device are disposed to be located within the range of the tooth crests of the rotor teeth of the pair of rotors, such that the first opening and the second opening of each resonant silencing device cannot be simultaneously in fluid communication with two compression containing cavities.
According to the above content, a distance D2 in a width direction of the rotor teeth between outer side edges of the first opening and the second opening of each resonant silencing device is smaller than a width D1 of the tooth crests of the rotor teeth of the corresponding rotors.
According to the above content, a center connection line connecting the first opening and the second opening of each resonant silencing device is not parallel to an extending direction of the rotor teeth.
According to the above content, the tooth crests of the rotor teeth of each pair of rotors have a center line parallel to the extending direction of the rotor teeth, and the first opening and the second opening of each resonant silencing device is located on two sides of the center line, respectively.
According to the above content, an inner diameter of the first communication channel is not smaller than that of the second communication channel.
According to the above content, each resonant silencing device is configured to form the preset inherent frequency through the volume of the resonant cavity, the length of the communication channel, and the inner diameter of the communication channel.
According to the above content, the pair of rotors comprises a male rotor and a female rotor, the rotor teeth comprise male rotor teeth and female rotor teeth, the male rotor teeth and the female rotor teeth are meshed with each other, the rotor containing cavity comprises a male rotor containing cavity and a female rotor containing cavity, the male rotor is disposed in the male rotor containing cavity, and the female rotor is disposed in the female rotor containing cavity, wherein the resonant silencing devices are disposed on the rotor containing cavity inner wall for defining the female rotor containing cavity.
According to the above content, the rotor shell comprises bodies and mounting plates, which are connected with each other, the mounting plates form at least a part of the rotor containing cavity inner wall, and the plurality of resonant silencing devices is disposed on the mounting plates, wherein the mounting plates and the plurality of resonant silencing devices are formed through a 3D printing process, a casting process, or a CNC machining process.
Other features, advantages and embodiments of the present application may be set forth or become apparent by consideration of the following detailed description, accompanying drawings, and claims. In addition, it should be understood that the above summary of the invention and the following specific embodiments are all exemplary and intended to provide further explanations rather than limit the scope of the present application to be claimed. However, the detailed description and specific examples indicate only preferred embodiments of the present application. Various changes and modifications within the spirit and scope of the present application will become apparent to those skilled in the art from this detailed description.

Brief Description of the Drawings

FIG. 1A is a stereoscopic structure diagram of a screw compressor according to an embodiment of the present application;
FIG. 1B is a side view of the screw compressor shown in FIG. 1A;
FIG. 2A is a sectional view of the screw compressor shown in FIG. 1B along a line A-A;
FIG. 2B is a sectional view of the screw compressor shown in FIG. 1B along a line B-B;
FIG. 3A is a stereoscopic structure diagram of an embodiment of a rotor shell in FIG. 1A;
FIG. 3B is an exploded view of the rotor shell in FIG. 3A;
FIG. 4A is a stereoscopic structure diagram of another embodiment of the rotor shell in FIG. 1A;
FIG. 4B is an exploded view of the rotor shell in FIG. 4A;
FIG. 5 is a partially expanded view of an embodiment of a rotor containing cavity inner wall in FIG. 3A;
FIGs. 6A-6C show a positional relationship between a resonant silencing device and a tooth crest in FIG. 5 during the rotation of a female rotor;
FIG. 7A is a schematic structural diagram of an embodiment of the resonant silencing device in FIG. 5;
FIG. 7B is an axial cross-sectional view of the resonant silencing device shown in FIG. 7A;
FIG. 8A is a schematic structural diagram of another embodiment of the resonant silencing device in FIG. 5;
FIG. 8B is an axial cross-sectional view of the resonant silencing device shown in FIG. 8A;
FIG. 9 is a partially expanded view of another embodiment of the rotor containing cavity inner wall in FIG. 3A;
FIGs. 10A-10E show a positional relationship between the resonant silencing device and a tooth crest in FIG. 9 during the rotation of the female rotor;
FIG. 11A is a schematic structural diagram of an embodiment of the resonant silencing device in FIG. 9;
FIG. 11B is an axial cross-sectional view of the resonant silencing device shown in FIG. 11A;
FIG. 12A is a schematic structural diagram of another embodiment of the resonant silencing device in FIG. 9; and
FIG. 12B is an axial cross-sectional view of the resonant silencing device shown in FIG. 12A.

Detailed Description of Embodiments

Various specific embodiments of the present application will be described below with reference to the accompanying drawings, which constitute a part of the specification. It should be understood that although terms, such as "front," "rear," "upper," "lower," "left," "right," "top," "bottom," etc., that represent directions are used in the present application to describe various example structural parts and elements of the present application, these terms used herein are for ease of illustration only and determined based on example orientations shown in the accompanying drawings. Since the embodiments disclosed in the present application may be disposed in different directions, these terms that represent directions are for illustration only and should not be regarded as limiting.
FIGs. 1A and 1B show a structure of a screw compressor 100 according to an embodiment of the present application, for illustrating an external structure of the screw compressor 100, wherein FIG. 1A is a stereoscopic structure diagram of the screw compressor 100, and FIG. 1B is a side view of FIG. 1A. As shown in FIGs. 1A and 1B, the screw compressor 100 comprises a shell 101, and the shell 101 is approximately in the shape of a long cylinder and comprises a motor shell 102, a rotor shell 103, and an exhaust shell 104 which are connected in sequence in a length direction. The motor shell 102 has a suction port 105, and the motor shell 102 is mainly used to accommodate a motor 212 (see FIG. 2A). The rotor shell 103 has a rotor containing cavity 213 (see FIG. 2A) therein, and the rotor containing cavity 213 is used to accommodate a pair of rotors 221, 222 to rotate therein. The exhaust shell 104 has an exhaust port 106 thereon, and the exhaust shell 104 is used to discharge the compressed gas from the exhaust port 106. Thus, after entering the shell 101 from the suction port 105, a gas flows approximately along a length direction, and is discharged out of the shell 101 from the exhaust port 106 after being compressed.
FIGs. 2A and 2B show an internal structure of the screw compressor 100 shown in FIG. 1A, wherein FIG. 2A shows a sectional view of the screw compressor 100 along a line A-A, and FIG. 2B shows a sectional view of the screw compressor 100 along a line B-B. As shown in FIGs. 2A and 2B, the rotor containing cavity 213 accommodates the pair of rotors arranged approximately parallel and side by side, wherein the pair of rotors 221, 222 comprises a male rotor 221 and a female rotor 222; the male rotor 221 is connected to the motor 212, and the male rotor 221 and the female rotor 222 are meshed with each other, such that the pair of rotors 221, 222 can be driven by the motor 212 to rotate respectively. The male rotor 221 and the female rotor 222 have axes parallel to each other, and the male rotor 221 and the female rotor 222 rotate about their respective axes. In the present embodiment, the extending directions of the axes are axial directions.
The male rotor 221 has helically extending rotor teeth 231, and the female rotor 222 has helically extending rotor teeth 232. The rotor teeth 231 of the male rotor 221 and the rotor teeth 232 of the female rotor 222 are meshed with each other; and several compression containing cavities 225 are formed between the meshed rotor teeth 231, 232 and the rotor containing cavity inner wall 218 for defining the rotor containing cavity 213. The rotor containing cavity 213 comprises a male rotor containing cavity 237 and a female rotor containing cavity 238, wherein the rotor containing cavity inner wall 218 comprises a male rotor containing cavity inner wall 236 and a female rotor containing cavity inner wall 235, the male rotor containing cavity 237 is defined and formed by the male rotor containing cavity inner wall 236, and the female rotor containing cavity 238 is defined and formed by the female rotor containing cavity inner wall 235. The male rotor 221 is disposed in the male rotor containing cavity 237, and tooth crests 233 of the rotor teeth 231 of the male rotor 221 are in sealing contact with the male rotor containing cavity inner wall 236. Similarly, the female rotor 222 is disposed in the female rotor containing cavity 238, and tooth crests 234 of the rotor teeth 232 of the female rotor 222 are in sealing contact with the female rotor containing cavity inner wall 235. In this embodiment, the sealing contact means that there are very small tooth crest clearances (not shown in the figures) between the tooth crests 233 and the male rotor containing cavity inner wall 236, and between the tooth crests 234 and the female rotor containing cavity inner wall 235. The tooth crest clearances are used to circulate lubricating oil, such that closed compression containing cavities 225 can be formed between the rotor teeth and the rotor containing cavity inner wall. And in this embodiment, the tooth crest refers to a position on the top of the rotor tooth, which is used to form an inter-tooth clearance with the corresponding rotor containing cavity inner wall.
As the pair of rotors 221, 222 rotates, each compression containing cavity 225 generates a volume change due to the intrusion or disengagement of the corresponding rotor tooth, such that the gas in the compression containing cavity 225 is gradually compressed. In each movement cycle of the intermeshed rotors, there are several identical compression containing cavities 225 that perform the same working process in sequence, such that each compression containing cavity 225 generates a periodic volume change. The pair of rotors 221, 222 has a rotor suction inlet 223 and a rotor exhaust outlet 224. Each compression containing cavity 225 independently moves axially from the rotor suction inlet 223 to the rotor exhaust outlet 224. At the same moment of the operation of the screw compressor 100, the volume and pressure of each compression containing cavity 225 are different, wherein in the direction of movement of the compression containing cavities 225, the pressures of these compression containing cavities 225 gradually increase. When the screw compressor 100 operates, during a movement cycle, the compression containing cavity 225 first communicates with the rotor suction inlet 223, such that the gas is sucked into the compression containing cavity 225 from the rotor suction inlet 223. As the pair of rotors 221, 222 rotates, the compression containing cavity 225 gradually moves axially toward the rotor exhaust outlet 224. The volume of the compression containing cavity 225 gradually decreases, such that the gas in the compression containing cavity 225 is gradually compressed, and the gas pressure gradually increases. The compressed gas is discharged from the rotor exhaust outlet 224 upon the compression containing cavity 225 moves to communicate with the rotor exhaust outlet 224. In this way, a process of suction, compression, and exhaust is completed. During the rotation and meshing process of the pair of rotors, the volume of the compression containing cavity decreases, and the gas in the compression containing cavity has noise energy. And during the rotation and meshing process of the pair of rotors, the rotors periodically pass through different positions of the containing cavity inner wall, which induces periodic pressure changes acting on the wall surface part of the containing cavity inner wall, thereby generating a pressure pulsation with high acoustic energy at the containing cavity inner wall and also causing vibration and noise of the screw compressor 100.
In this embodiment, the screw compressor 100 further comprises a plurality of resonant silencing devices 210, and these resonant silencing devices 210 are disposed on the rotor containing cavity inner wall 218. Each resonant silencing device 210 has a preset inherent frequency. Thus, the screw compressor 100 can absorb and attenuate the pressure pulsation energy acting at the rotor containing cavity inner wall 218 and in the compression containing cavities 225 by such a way that the resonant silencing device 210 forms resonance with sound waves having a preset inherent frequency during the process of the gas being compressed, and reduce the dynamic response of the shell 101, thereby reducing the vibration of the screw compressor 100 and the noise caused by the vibration.
FIGs. 3A and 3B show an embodiment of the rotor shell 103, in which FIG. 3A is a stereoscopic structure diagram of the rotor shell 103, and FIG. 3B is an exploded view of FIG. 3A. As shown in FIG. 3A, in this embodiment, a plurality of resonant silencing devices 210 is disposed on the female rotor containing cavity inner wall 235 for absorbing and attenuating the pressure pulsation energy acting on the female rotor containing cavity inner wall 235. This is because the tooth crests 234 of the rotor teeth 232 of the female rotor 222 are gentler than the tooth crests 233 of the rotor teeth 231 of the male rotor 221, such that a corresponding area where the tooth crests 234 of the female rotor 222 are in sealing contact with the female rotor containing cavity inner wall 235 is larger than that where the tooth crests 233 of the male rotor 221 are in sealing contact with the male rotor containing cavity inner wall 236. In some other embodiments, depending on different shapes of the tooth crests, it is also possible that the resonant silencing devices are disposed on the male rotor containing cavity inner wall 236, or the resonant silencing devices are disposed on the entire rotor containing cavity inner wall 218.
As shown in FIG. 3B, the rotor shell 103 comprises a body 341 and a mounting portion 340 which are connected to each other, wherein the plurality of resonant silencing devices 210 is disposed on the mounting portion 340. In this embodiment, the mounting portion 340 is used to form the rotor containing cavity inner wall 218. That is to say, the mounting portion 340 is shaped to define the rotor containing cavity 213 and accommodate the pair of rotors 221 and 222.
When manufacturing the rotor shell 103, the mounting portion 340 and the resonant silencing devices 210 are first integrally formed through a 3D printing process, a casting process, or a CNC machining process, and then the mounting portion 340 is connected to the body 341, such that these resonant silencing devices 210 are disposed on the rotor containing cavity inner wall 218. As an example, the mounting portion 340 may be connected to the body 341 through interference connection, riveting, welding, gluing, etc., wherein, in the embodiment shown in FIGs. 3A and 3B, the mounting portion 340 is shaped as an annular shape matching the body 341, the inside of which is used to dispose the resonant silencing devices 210, and the outer side of which is provided with a plurality of protruding connection points 342. A plurality of blind holes 343 is provided at the corresponding positions on the inner side of the body 341. Through the interference connection between the connection points 342 and the blind holes 343, the mounting portion 340 can be connected to the inner side of the body 341, such that the mounting portion 340 forms the rotor containing cavity inner wall 218.
The mounting portion 340 and the body 341 may be made of the same material, or may be made of different materials. In this embodiment, the mounting portion 340 is made of an aluminum alloy material with a certain expansion capability, and the body 341 is made of a cast steel or cast iron material with higher strength.
Those skilled in the art can understand that in some embodiments, the mounting portion 340 may not be included, and it is also possible that these resonant silencing devices 210 are directly formed integrally with the rotor containing cavity inner wall 218. As an example, when manufacturing the rotor shell 103, the rotor shell 103 as a whole is integrally formed through a 3D printing process, such that these resonant silencing devices 210 are directly formed on the rotor containing cavity inner wall 218 of the rotor shell 103. However, due to the high cost of 3D printing and CNC machining, the cost of the integrally formed rotor shell 103 is higher compared with the mounting portion 340 that can be manufactured separately.
FIGs. 4A and 4B show another embodiment of the rotor shell 403, in which FIG. 4A is a stereoscopic structure diagram of the rotor shell 403, and FIG. 4B is an exploded view of FIG. 4A. Similar to the rotor shell 103, the rotor shell 403 also comprises a mounting portion 440 and a body 441 which are connected to each other, and a plurality of resonant silencing devices 210 is disposed on the mounting portion 440. The difference is that in this embodiment, the rotor containing cavity inner wall 418 of the rotor shell 403 is formed by the mounting portion 440 and the body 441 together. That is to say, the mounting portion 440 only forms a part of the rotor containing cavity inner wall 418. Specifically, the rotor containing cavity inner wall 418 has a mounting groove 445, and the mounting portion 440 is connected into the mounting groove 445 through an interference connection or other means.
In this embodiment, the mounting portion 440 only forms a part of the rotor containing cavity inner wall 418, such that the size of the mounting portion 440 is smaller than that of the mounting portion 340, and in comparison, the cost of the rotor shell 403 is lower than that of the rotor shell 103. Correspondingly, for the rotor shell 403, the resonant silencing devices 210 can only be disposed in part of the rotor containing cavity inner wall 418, and the number of the resonant silencing devices 210 that can be disposed is also small.
FIG. 5 shows a partially expanded view of an embodiment of the rotor containing cavity inner wall 218 provided with the resonant silencing devices 210, which is used to show the arrangement structure of the resonant silencing devices 210. As shown in FIG. 5, the rotor containing cavity inner wall 218 is provided with a plurality of resonant silencing devices 210 arranged in sequence, wherein these resonant silencing devices 210 is an acoustic superstructure. Each resonant silencing device 210 has a preset inherent frequency. By forming resonance with sound waves having the same preset inherent frequency in the noise in the compression containing cavities 225, these resonant silencing devices 210 absorb and attenuate the pressure pulsation energy acting on the rotor containing cavity inner wall 218 and reduce the dynamic response of the shell 101, thereby reducing the vibration of the screw compressor 100 and the noise caused by the vibration. When at least a part of the resonant silencing devices 210 has different preset inherent frequencies, these resonant silencing devices 210 can reduce noise within a wide frequency range.
Each resonant silencing device 210 comprises a resonant cavity 753 and at least one communication channel 755 (see FIG. 7B), wherein in this embodiment, the at least one communication channel comprises a first communication channel 755. The first communication channel 755 extends, from outside to inside, into the resonant cavity 753 to form a resonant silencing structure. The first communication channel 755 forms a first opening 552 on the rotor containing cavity inner wall 218. The first communication channel 755 and the first opening 552 are in fluid communication with the resonant cavity 753. And as the pair of rotors 221, 222 rotates, the first communication channel 755 and the first opening 552 can further be in fluid communication with the compression containing cavity 225. Liquids such as lubricating oil mixed in the gas in the compression containing cavity 225 can enter the resonant cavity 753 from the first communication channel 755 and the first opening 552 or be discharged from the resonant cavity 753. Thus, the liquids will not affect the resonant silencing process of the resonant silencing devices 210.
As the pair of rotors 221, 222 rotates, the rotor teeth 232 of the female rotor 222 move along an axial direction, and the first opening 552 can be closed or opened by the tooth crests 234 of the corresponding rotor teeth 232 of the female rotor 222. When the first opening 552 is closed, the resonant cavity 753 is not in fluid communication with the compression containing cavity 225; and when the first opening 552 is opened, the resonant cavity 753 is in fluid communication with the compression containing cavity 225 through the first communication channel 755.
Those skilled in the art can understand that each resonant silencing device 210 may also comprise a greater number of communication channels and openings, which will be described in detail below in conjunction with embodiments.
FIGs. 6A-6C show the positional relationship between the resonant silencing device 210 and the tooth crest 234 during the rotation of the pair of rotors. As shown in FIGs. 6A-6C, as the pair of rotors rotates, the compression containing cavity 225 moves axially along the direction indicated by an arrow 660. And the spiral rotor teeth 232 also move axially along the direction indicated by the arrow 660 relative to the rotor containing cavity inner wall 218. The top of the tooth crest 234 is a high-pressure side, and the bottom of the tooth crest 234 is a low-pressure side. In this embodiment, as mentioned above, two compression containing cavities 225 are formed on the upper and lower sides of the tooth crest 234, respectively, wherein the two compression containing cavities 225 comprise a first compression containing cavity 661 and a second compression containing cavity 662, the compression containing cavity 661 is located above the tooth crest 234, and the second compression containing cavity 662 is located below the tooth crest 234, and the gas pressure in the first compression containing cavity 661 is higher than the gas pressure in the second compression containing cavity 662. That is to say, the first compression containing cavity 661 is a high-pressure compression containing cavity, and the second compression containing cavity 662 is a low-pressure compression containing cavity. It should be noted that the high pressure and low pressure here are relative to each other. For ease of display, only part of the tooth crest 234 of the rotor tooth 232 is shown in FIGs. 6A-6C.
As shown in FIG. 6A, the resonant silencing device 210 as a whole is located in the first compression containing cavity 661 above the tooth crest 234 of the rotor tooth 232. The first opening 552 of the resonant silencing device 210 is in fluid communication with the first compression containing cavity 661. At this time, the resonant silencing device 210 absorbs and attenuates the pressure pulsation energy in the first compression containing cavity 661 by forming resonance with sound waves having certain frequencies in the first compression containing cavity 661. And at this time, the first opening 552 of the resonant silencing device 210 has the same pressure as that in the first compression containing cavity 661. As the pair of rotors rotates, the pressure in the first compression containing cavity 661 continuously increases, and fluids such as lubricating oil in the containing cavity 661 will flow into the resonant cavity 753. As the pair of rotors further rotates, the tooth crest 234 of the rotor tooth 232 moves along the direction of the arrow 660 relative to the resonant silencing device 210, and the tooth crest 234 and the resonant silencing device 210 reach the position shown in FIG. 6B.
As shown in FIG. 6B, the resonant silencing device 210 is located within the range of the tooth crest 234, and the first opening 552 begins to be closed by the tooth crest 234. At this time, the resonant silencing device 210 is not in fluid communication with the compression containing cavity 225, and the resonant cavity 753 and the first opening 552 still have the same high pressure as that they have when separated from the first compression containing cavity 661. As the pair of rotors continues to rotate, the tooth crest 234 continues to move along the direction of the arrow 660 relative to the resonant silencing device 210, and the tooth crest 234 and the resonant silencing device 210 reach the position shown in FIG. 6C.
As shown in FIG. 6C, a part of the resonant silencing device 210 is still located within the range of the tooth crest 234, and the other part thereof is located in the second compression containing cavity 662 below the tooth crest 234. The first opening 552 is opened and in fluid communication with the second compression containing cavity 662. At this time, the resonant cavity 753 has the same high pressure as that it has when separated from the first compression containing cavity 661, such that there is a certain pressure difference between the resonant cavity 753 and the second compression containing cavity 662, which enables the fluid in the resonant cavity 753 to be automatically discharged into the second compression containing cavity 662 through the first communication channel 755 and the first opening 552. And at this time, due to the pressure change acting on the rotor containing cavity inner wall at the resonant silencing device 210, the resonant silencing device 210 can absorb and attenuate the pressure pulsation energy acting on the containing cavity inner wall at the resonant silencing device 210 by forming resonance with sound waves having certain frequencies.
As the pair of rotors continues to rotate, the tooth crest 234 continues to move along the direction of the arrow 660 relative to the resonant silencing device 210 until the resonant silencing device 210 as a whole is located in the second compression containing cavity 662. For the tooth crest of the next rotor tooth (not shown in the figures), the tooth crest and the resonant silencing device 210 are again in the position shown in FIG. 6A. As a result, the tooth crests of the rotor teeth move cyclically relative to the resonant silencing device 210. The resonant silencing devices 210 sequentially absorb and attenuate the pressure pulsation energy in each compression containing cavity and at the containing cavity inner wall through resonance, and timely discharge liquids such as lubricating oil that enter the resonant cavity of each resonant silencing device 210.
FIGs. 7A and 7B show the specific structure of an embodiment of the resonant silencing device 210, wherein FIG. 7A is a stereoscopic schematic perspective view of the resonant silencing device 210, and FIG. 7B is an axial cross-sectional view through the center of the first opening 552 in FIG. 7A. In order to illustrate the specific structure of the resonant silencing device 210 more clearly, the resonant silencing device 210 in FIG. 7A schematically shows, around its resonant cavity 753, a cylindrical containing cavity wall 759; and the actual containing cavity wall is formed by mounting portions spaced between the respective resonant silencing devices 210.
As shown in FIGs. 7A and 7B, the resonant cavity 753 is in the shape of a cylinder. The mounting portion 340 has a front wall 758 and a rear wall 763, and the resonant cavity 753 of the resonant silencing device 210 is disposed between the front wall 758 and the rear wall 763. In this embodiment, the first communication channel 755 is formed by a tube extending into the resonant cavity 753 from the front wall 758 and extending for a certain length, and a first opening 552 is formed on the front wall 758. Thus, when the first opening 552 is opened, the first communication channel 755 can be in fluid communication with the resonant cavity 753 and the corresponding compression containing cavity 225. In this embodiment, the first communication channel 755 is disposed at the bottom of the containing cavity wall 759. The extending direction of the first communication channel 755 is approximately consistent with the axial direction of the resonant cavity 753. Those skilled in the art can understand that, for convenience of description, the first communication channel 755 in this embodiment is disposed at the bottom of the resonant silencing device 210, and in other embodiments, the first communication channel 755 may also be disposed in other directions.
In this embodiment, the first communication channel 755 is defined and formed by a tube 757. In the extending direction of the first communication channel 755, the bottom of the tube 757 and the containing cavity wall 759 are integrally formed. The first communication channel 755 has a first end 764 and a second end 765, wherein the first end 764 is located in the resonant cavity 753, and the second end 765 forms the first opening 552. The bottom of the first communication channel 755 at least at a first end 764 is not higher than the containing cavity wall 759 at the same location, such that the liquid in the resonant cavity 753 can enter the first communication channel 755. And the bottom of the first communication channel 755 at least at the second end 765 is not higher than that at the first end 764, such that the liquid in the first communication channel 755 can be discharged from the second end 765 to the corresponding compression containing cavity 225. In some embodiments, the inner surface of the bottom of the containing cavity wall 759 extends continuously through the first end 764 of the first communication channel 755 to the second end 765.
In some embodiments, at the first end 764 of the first communication channel 755, the inner surface of the bottom of the containing cavity wall 759 at a connection part is slightly higher than the inner surface of the bottom of the first communication channel 755. In some embodiments, the inner surface of the bottom of the first communication channel 755 may not extend along the axial direction, but extend obliquely downward in the direction from the first end 764 to the second end 765. That is to say, in the extending direction of the first communication channel 755, the inner surface of the bottom of the containing cavity wall 759, the inner surface of the first end 764, and the inner surface of the second end 765 are approximately flush or gradually decrease, such that the liquid in the resonant cavity 753 can flow out smoothly without being accumulated in the resonant cavity 753. As a specific embodiment, the inner surface of the bottom of the first communication channel 755 is disposed tangentially to the inner surface of the containing cavity wall 759.
In this embodiment, the resonant cavity 753 and the first communication channel 755 together form the resonant silencing device 210. By setting the volume of the resonant cavity 753, the length of the first communication channel 755, and the inner diameter of the first communication channel 755, each resonant silencing device 210 can have a preset inherent frequency, and the plurality of resonant silencing devices 210 can have different preset inherent frequencies.
In this embodiment, the first communication channel 755 is used not only for receiving the sound waves but also for discharging the liquid. Specifically, the sound waves can pass from the compression containing cavity 225 through the first opening 552 to excite the gas in the resonant cavity to generate resonance, thereby achieving a silencing effect. Even if the liquid in the compression containing cavity 225 also enters the resonant cavity 753, since the resonant cavity 753 and the compression containing cavity 225 can have a pressure difference at certain moments during the rotation of the rotor, the liquid entering the resonant cavity 753 can be timely discharged from the resonant cavity 753. In this way, the condition that the resonant silencing device 210 is unable to reach the preset inherent frequency as expected due to being affected by the liquid in the resonant cavity 753 can be avoided, thereby ensuring the silencing effect of the resonant silencing device 210.
In order to further reduce the pressure impact caused by the pressure pulsation of the compressed gas on the cavity structure of the resonant cavity 753 and reduce the pressure loss of the compressed gas, in this embodiment, the inner surface of the front wall 758 is set as a partially spherical shape as well. And the inner surface of the rear wall 763 is set as a smooth curved surface. Those skilled in the art can understand that when the mounting portion is made of a material with higher strength, the inner surfaces of the front wall 758 and the rear wall 763 can also be set to be in the shape of a plane, etc.
By setting the positions and shapes of the first communication channel 755, the front wall 758, and the rear wall 763, the resonant silencing device 210 of the present application may well avoid the impact of the high-pressure compressed gas in the compression containing cavity on the resonant silencing device 210, and timely discharge the liquid in the resonant cavity 753, which is suitable for working in an environment with high pressure and the presence of liquid, and thus can be suitable for being disposed on the rotor containing cavity inner wall of the screw compressor.
Those skilled in the art can understand that, as described above, upper, lower, top, bottom, high, and low are relative to the orientation shown in the figures and do not represent the orientation of the resonant silencing device in the screw compressor.
FIGs. 8A and 8B show the specific structure of another embodiment of a resonant silencing device 810, wherein FIG. 8A is a stereoscopic schematic perspective view of the resonant silencing device 810, and FIG. 8B is an axial cross-sectional view through the center of the first opening 852 in FIG. 8A. As shown in FIGs. 8A and 8B, the structure of the resonant silencing device 810 is approximately the same as that of the resonant silencing device 210, wherein the difference is that the shapes of the first communication channel 855 and the resonant cavity 853 are different from those of the resonant silencing device 210. Specifically, in this embodiment, the resonant cavity 853 is in the shape of a sphere, wherein the front wall 858, the containing cavity wall 859, and the rear wall 863 are disposed around the spherical resonant cavity 853, and the spherical resonant cavity 853 can further reduce the impact of high-pressure compressed gas and facilitate liquid discharge. The first communication channel 855 has a fan-shaped shape with a gentle bottom surface to increase the volume of liquid that can be discharged.
FIG. 9 shows a partially expanded view of another embodiment of the rotor containing cavity inner wall 218 provided with the resonant silencing devices 910, for illustrating the arrangement structure of the resonant silencing devices 910. As shown in FIG. 9, the structure of the resonant silencing device 910 is approximately the same as the resonant silencing device 210, wherein the difference is that the resonant silencing device 910 comprises a resonant cavity 1153 and two communication channels (see FIG. 11B), wherein these two communication channels are a first communication channel 1155 and a second communication channel 1154. The first communication channel 1155 forms a first opening 952 on the rotor containing cavity inner wall 218, and the second communication channel 1154 forms a second opening 951 on the rotor containing cavity inner wall 218. The first communication channel 1155, the first opening 952, the second communication channel 1154, and the second opening 951 are all in fluid communication with the resonant cavity 1153. And they can further be in fluid communication with the compression containing cavity 225, such that liquids such as lubricating oil mixed in the gas in the compression containing cavity 225 can enter the resonant cavity 753 or be discharged from the resonant cavity 753, as the pair of rotors 221, 222 rotates. For example, as the pair of rotors 221, 222 rotates, the resonant cavity 1153 is first in fluid communication with the high-pressure compression containing cavity 225 through the second communication channel 1154 and the second opening 951, and is then in fluid communication with the low-pressure compression containing cavity 225 through the first communication channel 1155 and the first opening 952, to discharge the fluid in the resonant cavity 1153 in real time.
In this embodiment, the first opening 952 and the second opening 951 need to be disposed in a certain manner to ensure the normal operation of the screw compressor 100. The first opening 952 and the second opening 951 of the resonant silencing device 210 are not simultaneously in fluid communication with the two compression containing cavities 225. This is because, if the first opening 952 and the second opening 951 of the resonant silencing device 210 are simultaneously in fluid communication with the two compression containing cavities 225, and due to the different pressure in each compression containing cavity 225, the two compression containing cavities 225 being in fluid communication will cause the performance of the screw compressor 100 to decrease, or even cause compression failure.
Specifically, each resonant silencing device 210 is configured such that the first opening 952 and the second opening 951 of the resonant silencing device 210 need to be disposed in the rotor containing cavity inner wall 218 within the range of the tooth crests 234 of the rotor teeth 232 of the female rotor 222, such that the first opening 952 and the second opening 951 of each resonant silencing device 210 cannot be simultaneously in fluid communication with two different compression containing cavities 225. During the operation of the screw compressor 100, the volumes of two different compression containing cavities 225 are different, so the gas pressures in the different compression containing cavities 225 are also different. If the first opening 952 and the second opening 951 of the resonant silencing device 210 are simultaneously in fluid communication with two different compression containing cavities 225, compression failure of the screw compressor 100 will be caused. As an example, the distance D2 in the width direction of the rotor teeth 232 between the outer side edges of the first opening 952 and the second opening 951 of each resonant silencing device 210 is smaller than the width D1 of the tooth crest 234.
Thus, as the pair of rotors rotates, the rotor teeth 232 of the female rotor 222 move along the axial direction, and the first opening 952 and the second opening 951 of each resonant silencing device 210 may be simultaneously in fluid communication with one compression containing cavity 225, or are simultaneously closed by the tooth crest 234, or one of them is in fluid communication with the compression containing cavity 225 and the other is closed by the tooth crest 234.
And in some embodiments, the center connection line between the first opening 952 and the second opening 951 of the resonant silencing device 210 is not parallel to the extending direction of the corresponding rotor tooth, such that as the rotor rotates, the tooth crest 234 can close the first opening 952 and the second opening 951 in sequence, thereby prolonging the communication time between the resonant cavity 1153 and the high-pressure first compression containing cavity 661, such that the resonant cavity 1153 and the low-pressure second compression containing cavity 662 can have a larger pressure difference, which is more conducive to the automatic discharge of liquid from the resonant cavity 1153 to the low-pressure second compression containing cavity 662.
As an example, the tooth crest 234 of the rotor tooth 232 of the female rotor 222 has a center line parallel to the extending direction of the rotor tooth 232, and the first opening 952 and the second opening 951 are located on two sides of the center line, respectively. In other embodiments, the center connection line connecting the first opening 952 and the second opening 951 of the resonant silencing device 210 may also be parallel to the extending direction of the corresponding rotor tooth, and the first opening 952 and the second opening 951 are set to have outer contours with different sizes, such that during the rotation of the rotor, at least at certain moments, one of the first opening 952 and the second opening 951 is closed by the tooth crest 234 and the other can be in fluid communication with the compression containing cavity. Those skilled in the art can understand that in this embodiment, the first opening 952 and the second opening 951 are set to be in a circular shape for ease of description, but in other embodiments, the first opening 952 and the second opening 951 may also be in other shapes.
FIGs. 10A-10E show the positional relationship between the resonant silencing device 910 and the tooth crest 234 during the rotation of the pair of rotors. As shown in FIGs. 10A-10E, as the pair of rotors rotates, the compression containing cavity 225 moves axially along the direction indicated by an arrow 660. And the spiral rotor teeth 232 also move axially along the direction indicated by the arrow 660 relative to the rotor containing cavity inner wall 218. The top of the tooth crest 234 is a high-pressure side, and the bottom of the tooth crest 234 is a low-pressure side. In this embodiment, as mentioned above, two compression containing cavities 225 are formed on the upper and lower sides of the tooth crest 234, respectively, wherein the two compression containing cavities 225 comprise a first compression containing cavity 661 and a second compression containing cavity 662, the first compression containing cavity 661 is located above the tooth crest 234, the second compression containing cavity 662 is located below the tooth crest 234, and the gas pressure in the first compression containing cavity 661 is higher than the gas pressure in the second compression containing cavity 662. That is to say, the first compression containing cavity 661 is a high-pressure compression containing cavity, and the second compression containing cavity 662 is a low-pressure compression containing cavity. It should be noted that the high pressure and low pressure here are relative to each other. For ease of display, only part of the tooth crest 234 of the rotor tooth 232 is shown in FIGs. 10A-10E.
As shown in FIG. 10A, the resonant silencing device 910 as a whole is located in the first compression containing cavity 661 above the tooth crest 234 of the rotor tooth 232. The first opening 952 and the second opening 951 of the resonant silencing device 910 are both in fluid communication with the first compression containing cavity 661. At this time, the resonant silencing device 910 absorbs and attenuates the pressure pulsation energy in the first compression containing cavity 661 by forming resonance with sound waves having certain frequencies in the first compression containing cavity 661. At this time, both the first opening 952 and the second opening 951 of the resonant silencing device have the same pressure as that in the first compression containing cavity 661. As the pair of rotors rotates, the pressure in the first compression containing cavity 661 continuously increases, and fluids such as lubricating oil in the containing cavity 661 will flow into the resonant cavity 1153. As the screw rotor further rotates, the tooth crest 234 of the rotor tooth 232 moves along the direction of the arrow 660 relative to the resonant silencing device 910, and the tooth crest 234 and the resonant silencing device 910 reach the position shown in FIG. 10B.
As shown in FIG. 10B, a part of the resonant silencing device 910 is located within the range of the tooth crest 234, and the other part is still located in the first compression containing cavity 661. The second opening 951 of the resonant silencing device 910 is still in fluid communication with the first compression containing cavity 661, and the first opening 952 of the resonant silencing device 910 is closed by the tooth crest 234. At this time, the second opening 951 of the resonant cavity 1153 has the same high pressure as that in the first compression containing cavity 661, the first opening 952 is closed by the tooth crest 234, and as the rotor rotates, the pressure in the first compression containing cavity 661 still increases; therefore, fluids such as lubricating oil in the first compression containing cavity 661 can continue to flow into the resonant cavity 1153 through the second opening 951, and the fluid pressure in the resonant cavity 1153 continues to increase. As the pair of rotors continues to rotate, the tooth crest 234 continues to move along the direction of the arrow 660 relative to the resonant silencing device 910, and the tooth crest 234 and the resonant silencing device 910 reach the position shown in FIG. 10C.
As shown in FIG. 10C, the resonant silencing device 910 as a whole is located within the range of the tooth crest 234. The first opening 952 and the second opening 951 of the resonant silencing device 910 are both closed by the tooth crest 234. At this time, the resonant silencing device 910 is not in fluid communication with any compression containing cavity 225. As the pair of rotors continues to rotate, the tooth crest 234 continues to move along the direction of the arrow 660 relative to the resonant silencing device 910, and the tooth crest 234 and the resonant silencing device 910 reach the position shown in FIG. 10D.
As shown in FIG.10D, a part of the resonant silencing device 910 is still located within the range of the tooth crest 234, and the other part thereof is located in the second compression containing cavity 662 below the tooth crest 234. The second opening 951 of the resonant silencing device 910 is closed by the tooth crest 234, and the first opening 952 of the resonant silencing device 910 is in fluid communication with the second compression containing cavity 662. At this time, the second opening 951 of the resonant silencing device has the same high pressure as it has when separated from the first compression containing cavity 661, and the first opening 952 has the same low pressure as that in the second compression containing cavity 662. Therefore, a pressure difference is formed between the resonant cavity 1153 and the second compression containing cavity 662, wherein this pressure difference causes the fluid in the resonant cavity 1153 to be automatically discharged into the second compression containing cavity 662 at the moment when the first opening 952 comes to communicating with the second compression containing cavity 662. And at this time, due to the pressure change acting on the containing cavity inner wall at the resonant silencing device 910, the resonant silencing device 910 can absorb and attenuate the pressure pulsation energy acting on the containing cavity inner wall at the resonant silencing device 910 by forming resonance with sound waves having certain frequencies. As the pair of rotors continues to rotate, the tooth crest 234 continues to move along the direction of the arrow 660 relative to the resonant silencing device 910, and the tooth crest 234 and the resonant silencing device 910 reach the position shown in FIG. 10E.
As shown in FIG. 10E, the resonant silencing device 910 as a whole is located in the second compression containing cavity 662. The first opening 952 and the second opening 951 of the resonant silencing device 910 are both in fluid communication with the second compression containing cavity 662. At this time, the first opening 952 and the second opening 951 of the resonant silencing device 910 both have the same pressure as that in the second compression containing cavity 662. The resonant silencing device 910 absorbs and attenuates the pressure pulsation energy in the second compression containing cavity 662 by forming resonance with sound waves in the second compression containing cavity 662. As the pair of rotors continues to rotate, the tooth crest (not shown in the figures) of the next rotor tooth moves along the direction of the arrow 660 relative to the resonant silencing device 910. For the tooth crest of the next rotor tooth, the tooth crest and resonant silencing device 910 are again at the position shown in FIG. 10A. As a result, the tooth crests of the rotor teeth move cyclically relative to the resonant silencing device 910. The resonant silencing devices 910 sequentially absorb and attenuate the pressure pulsation energy in each compression containing cavity and at the containing cavity inner wall through resonance, and timely discharge fluids such as lubricating oil that enter the resonant cavity of each resonant silencing device 910.
Those skilled in the art can understand that compared with the resonant silencing device 210 with only one communication channel, in this embodiment, in the state shown in FIG. 10B, the resonant cavity 1153 can still be in fluid communication with the first compression containing cavity 661 through the second opening 951. However, as the rotor rotates, when the first compression containing cavity 661 is in the state shown in FIG. 10B, the pressure continues to increase. Thus, under the same conditions, the pressure in the resonant cavity 1153 in the state shown in FIG. 10C will be greater than that in the resonant cavity 753 in the state shown in FIG. 6B. Therefore, when the resonant silencing device 910 discharges the fluid in the resonant cavity 1153 to the second compression containing cavity 662, there can be a larger pressure difference between the resonant cavity 1153 and the second compression containing cavity 662, such that the fluid in the resonant cavity 1153 is discharged more completely.
FIGs. 11A and 11B show the specific structure of an embodiment of the resonant silencing device 910, wherein FIG. 11A is a stereoscopic schematic perspective view of the resonant silencing device 910, and FIG. 11B is an axial cross-sectional view through the center of the first opening 952 and the center of the second opening 951 in FIG. 11A. In order to illustrate the specific structure of the resonant silencing device 910 more clearly, the resonant silencing device 910 in FIG. 11A schematically shows, around its resonant cavity 1153, a cylindrical containing cavity wall; and the actual containing cavity wall is formed by mounting portions spaced between the respective resonant silencing devices 910.
As shown in FIGs. 11A and 11B, the resonant silencing device 910 has a similar structure to the resonant silencing device 210, and similar parts will not be described again; wherein the difference is that the resonant silencing device 910 further comprises a second communication channel 1154 and a second opening 951. The second communication channel 1154 is disposed above the first communication channel 1155, and the second communication channel 1154 is formed by a through hole extending through the front wall 1158, wherein the second communication channel 1154 forms a second opening 951 on the front wall 1158. In this embodiment, the first communication channel 1155 is disposed at the bottom of the containing cavity wall 1159, and the second communication channel 1154 is disposed at the top of the containing cavity wall 1159. The extending directions of the first communication channel 1155 and the second communication channel 1154 are approximately parallel, and both are consistent with the axial direction of the resonant cavity 1153. Those skilled in the art can understand that the first communication channel 1155 and the second communication channel 1154 in this embodiment are approximately symmetrically disposed at the top and bottom of the resonant silencing device 210, and in other embodiments, the first communication channel 1155 and the second communication channel 1154 may also be disposed in other positions.
In this embodiment, the resonant cavity 1153, the first communication channel 1155, and the second communication channel 1154 together form the resonant silencing device 910. On the premise that the second communication channel 1154 has a fixed inner diameter, by setting the volume of the resonant cavity 1153, the length of the first communication channel 1155, and the inner diameter of the first communication channel 1155, each resonant silencing device 910 can have a preset inherent frequency, and the plurality of resonant silencing devices 910 can have different preset inherent frequencies. As an example, the liquid in the resonant cavity 1153 is mainly discharged through the first communication channel 1155, such that the inner diameter of the first communication channel 1155 may be set to be larger than that of the second communication channel 1154.
In this embodiment, the first opening 952, the first communication channel 1155, the second opening 951, and the second communication channel 1154 not only are used to receive sound waves, but also can be used to discharge liquid. In this way, the condition that the resonant silencing device 910 is unable to reach the preset inherent frequency as expected due to being affected by the liquid in the resonant cavity 1153 can be avoided, thereby ensuring the silencing effect of the resonant silencing device 910.
Those skilled in the art can understand that, as described above, upper, lower, top, bottom, high, and low are relative to the orientation shown in the figures and do not represent the orientation of the resonant silencing device in the screw compressor.
FIGs. 12A and 12B show the specific structure of another embodiment of a resonant silencing device 1210, wherein FIG. 12A is a stereoscopic schematic perspective view of the resonant silencing device 1210, and FIG. 12B is an axial cross-sectional view through the center of the first opening 1252 and the center of the second opening 1251 in FIG. 12A. As shown in FIGs. 12A and 12B, the structure of the resonant silencing device 1210 is approximately the same as that of the resonant silencing device 910, wherein the difference is that the shape of the second communication channel 1254 is different. Specifically, in this embodiment, the second communication channel 1254 is similar to the first communication channel 1255, wherein the second communication channel 1254 is as well formed by a tube extending into the resonant cavity 1253 from the front wall 1258 and extending for a certain length, and a second opening 1251 is formed on the front wall 1258. That is to say, in this embodiment, both the second communication channel 1254 and the first communication channel 1255 are formed by tubes extending inwardly from the front wall 1258. As an example, the top of the second communication channel 1254 is disposed tangentially to the inner surface of the containing cavity wall 1259. In this way, both the second communication channel 1254 and the first communication channel 1255 are disposed to be tangent to the inner surface of the containing cavity wall 1259, such that not only is the liquid in the resonant cavity 1253 more conveniently discharged, but also the spacing between the second communication channel 1254 and the first communication channel 1255 can be increased as much as possible, which is particularly suitable for a resonant silencing device with a small resonant cavity 1253.
In existing screw compressors, the compressed gas is compressed in each compression containing cavity through the rotation of the pair of rotors, and the gas with increased pressure has noise energy. And during the process that the gas in the compression containing cavity is compressed, pressure fluctuations acting on the rotor containing cavity inner wall are induced, which will generate pressure pulsations with high acoustic energy at the containing cavity inner wall, causing a dynamic response of the rotor shell, and in turn causing the vibration and the noise of the screw compressor.
In the screw compressor of the present application, the resonant silencing devices are disposed on the rotor containing cavity inner wall, such that the noise of the screw compressor can be eliminated more quickly and efficiently directly at the position where the gas pressure is highest and the position where the pressure pulsation is generated. Moreover, the resonant silencing devices of the present application can ensure that the resonant silencing devices will not affect the operation of the screw compressor by setting positions of a communication channel and an opening.
Moreover, by setting the positions and shapes of each communication channel, the front wall, and the rear wall, the resonant silencing device of the present application may well avoid the impact of the high-pressure compressed gas in the compression containing cavity on the resonant silencing device, and prevent the structure of the resonant silencing device from being destroyed by the pressure pulse, and meanwhile, the liquid in the resonant cavity may be timely discharged to ensure the stability of the silencing effect of the resonant silencing device; therefore, the resonant silencing device may be disposed on the rotor containing cavity inner wall corresponding to the rotor containing cavity with very high pressure pulsation energy.
In addition, the resonant silencing device of the present application has an acoustic superstructure, which achieves the purpose of reducing noise by forming resonance with sound waves having certain frequencies in the noise to reduce the pressure pulsation energy, such that not only is the silencing effect of each resonant silencing device good and the occupied spacesmall, but also a plurality of resonant silencing devices with different preset inherent frequencies can also eliminate the noise in the compression containing cavity within a wide frequency range.
Although the present disclosure has been described in conjunction with the examples of embodiments outlined above, various alternatives, modifications, variations, improvements, and/or substantial equivalents, whether known or foreseeable now or soon, may become apparent to those of ordinary skill in the art. Accordingly, the examples of embodiments of the present disclosure set forth above are intended to be illustrative rather than restrictive. Various changes may be made without departing from the spirit or scope of the present disclosure. Accordingly, the present disclosure is intended to embrace all known or earlier developed alternatives, modifications, variations, improvements, and/or substantial equivalents. The technical effects and technical problems in the specification are exemplary rather than restrictive. It should be noted that the embodiments described in the specification may have other technical effects and may solve other technical problems.

Claims

A screw compressor, characterized in that the screw compressor comprises:
a shell (101), the shell (101) comprising a rotor shell (103), and the rotor shell (103) having a rotor containing cavity (213) and a rotor containing cavity inner wall (218) for defining the rotor containing cavity (213);

a pair of rotors (221, 222), the pair of rotors (221, 222) being disposed in the rotor containing cavity (213), wherein each rotor (221, 222) has rotor teeth (231, 232), compression containing cavities (225) are able to be formed between the rotor teeth (231, 232) of the pair of rotors (221, 222) and the rotor containing cavity inner wall (218), and the pair of rotors (221, 222) has a rotor suction inlet (223) and a rotor exhaust outlet (224), and wherein the pair of rotors (221, 222) is configured such that as the pair of rotors (221, 222) rotates, the compression containing cavities (225) periodically generate volume changes such that gas in the compression containing cavities (225) can move from the rotor suction inlet (223) to the rotor exhaust outlet (224) after being compressed and raised in gas pressure; and

a plurality of resonant silencing devices (210), the plurality of resonant silencing devices (210) being disposed on the rotor containing cavity inner wall (218), and each resonant silencing device (210) being configured to have a preset inherent frequency, so as to absorb and attenuate pressure pulsation energy by forming resonance with sound waves having the preset inherent frequency, thereby reducing noise.
The screw compressor according to Claim 1, characterized in that:
the resonant silencing devices (210) are an acoustic superstructure, wherein at least a part of the resonant silencing devices (210) is configured to have different preset inherent frequencies.
The screw compressor according to Claim 2, characterized in that:
the resonant silencing devices (210) comprise a resonant cavity (753) and at least one communication channel (755), and the at least one communication channel (755) is in fluid communication with the resonant cavity (753);

wherein each resonant silencing device (210) is configured such that as the pair of rotors (221, 222) rotates, a pressure difference exists between the resonant cavity (753) and the compression containing cavity (225) outside the resonant silencing device (210), and the at least one communication channel (755) can be in fluid communication with the resonant cavity (753) and the compression containing cavity (225) outside the resonant silencing device (210), such that a liquid in the compression containing cavity (225) can enter the resonant cavity (753) from the at least one communication channel (755) or be discharged from the resonant cavity (753).
The screw compressor according to Claim 3, characterized in that:
in an extending direction of the at least one communication channel (755), for the bottom of the at least one communication channel (755), one end (765) thereof at least at the compression containing cavity (225) is not higher than one end (764) thereof in the resonant cavity (753), such that a liquid in the resonant cavity (753) is discharged to the compression containing cavity (225) through the at least one communication channel (755).
The screw compressor according to Claim 4, characterized in that:
the rotor containing cavity inner wall (218) comprises a front wall (758) and a containing cavity wall (759), and the containing cavity wall (759) is disposed around the resonant cavity (753);

wherein for the bottom of the at least one communication channel (755), one end (764) thereof in the resonant cavity (753) is not higher than the containing cavity wall (759) at the same location, such that the liquid in the resonant cavity (753) can enter the at least one communication channel (755).
The screw compressor according to Claim 5, characterized in that:
an inner surface of the bottom of the at least one communication channel (755) is disposed tangentially to an inner surface of the containing cavity wall (759).
The screw compressor according to Claim 6, characterized in that:
the rotor containing cavity inner wall (218) further comprises a rear wall (763), the rear wall (763) is disposed opposite to an inner surface of the front wall (758), the inner surface of the front wall (758) of the rotor containing cavity inner wall (218) is a partially spherical surface, and an inner surface of the rear wall (763) is a smoothly curved surface.
The screw compressor according to Claim 7, characterized in that:
an inner surface of a containing cavity wall (859) of the resonant cavity (853) is spherical.
The screw compressor according to Claim 5, characterized in that:
the at least one communication channel (1154, 1155) comprises a first communication channel (1155) and a second communication channel (1154), the resonant silencing devices (210) are configured such that as the pair of rotors (221, 222) rotates, the resonant cavity (1153) is first in fluid communication with a high-pressure compression containing cavity (225) through the second communication channel (1154), and is then in fluid communication with a low-pressure compression containing cavity (225) through the first communication channel (1155), so as to discharge the liquid in the resonant cavity (1153).
The screw compressor according to Claim 9, characterized in that:
the rotor teeth (231, 232) of the pair of rotors (221, 222) have tooth crests (233, 234);

the first communication channel (1155) and the second communication channel (1154) form a first opening (952) and a second opening (951) on the front wall (758), respectively;

the first opening (952) and the second opening (951) of each resonant silencing device (210) are disposed to be located within the range of the tooth crests (233, 234) of the rotor teeth (231, 232) of the pair of rotors (221, 222), such that the first opening (952) and the second opening (951) of each resonant silencing device (210) cannot be simultaneously in fluid communication with two compression containing cavities (225).
The screw compressor according to Claim 10, characterized in that:
a distance D2 in a width direction of the rotor teeth (231, 232) between outer side edges of the first opening (952) and the second opening (951) of each resonant silencing device (210) is smaller than a width D1 of the tooth crests (233, 234) of the rotor teeth (231, 232) of the corresponding rotors (221, 222).
The screw compressor according to Claim 10, characterized in that:
a center connection line connecting the first opening (952) and the second opening (951) of each resonant silencing device (210) is not parallel to an extending direction of the rotor teeth (231, 232).
The screw compressor according to Claim 12, characterized in that:
the tooth crests (233, 234) of the rotor teeth (231, 232) of each pair of rotors (221, 222) have a center line parallel to the extending direction of the rotor teeth (231, 232), and the first opening (952) and the second opening (951) of each resonant silencing device (210) are located on two sides of the center line, respectively.
The screw compressor according to Claim 9, characterized in that:
an inner diameter of the first communication channel (1155) is not smaller than that of the second communication channel (1154).
The screw compressor according to Claim 3, characterized in that:
each resonant silencing device (210) is configured to form the preset inherent frequency through the volume of the resonant cavity (753), the length of the communication channel (755), and the inner diameter of the communication channel (755).
The screw compressor according to Claim 3, characterized in that:
the pair of rotors (221, 222) comprises a male rotor (221) and a female rotor (222), the rotor teeth (231, 232) comprise male rotor teeth (231) and female rotor teeth (232), the male rotor teeth (231) and the female rotor teeth (232) are meshed with each other, the rotor containing cavity (213) comprises a male rotor containing cavity (237) and a female rotor containing cavity (238), the male rotor (221) is disposed in the male rotor containing cavity (237), and the female rotor (222) is disposed in the female rotor containing cavity (238);

wherein the resonant silencing devices (210) are disposed on the rotor containing cavity inner wall (218) for defining the female rotor containing cavity (238).
The screw compressor according to any one of Claims 1-15, characterized in that:
the rotor shell (103) comprises bodies (341, 441) and mounting plates (340, 440), which are connected with each other, the mounting plates (340, 440) form at least a part of the rotor containing cavity inner wall (218), and the plurality of resonant silencing devices (210) is disposed on the mounting plates (340, 440), wherein the mounting plates (340, 440) and the plurality of resonant silencing devices (210) are formed through a 3D printing process, a casting process, or a CNC machining process.