Screw compressor

Abstract

The present invention relates to a screw compressor, which includes a body, a rotor member, a cam structure and a volume adjustment assembly. The rotor member is disposed in the rotor cavity of the body. The rotation of the rotor member realizes the compression of gas, and the compressed gas is discharged into the discharge cavity. Since a cam structure is provided on the rotor member and the cam structure rotates synchronously with the rotor member, the abutting convex teeth on the cam structure are used to abut against the volume adjustment assembly to realize the adjustment of the communication volume between the adjustment cavity and the discharge. The above screw compressor uses the cooperation between the abutting convex teeth on the cam structure and the volume adjustment assembly, avoiding the use of electronic chips or electronic actuating elements to control the movement of the volume adjustment assembly, without the need to connect an external power supply, nor the need for components that manually or cooperate with other external devices to control the movement of the volume adjustment assembly, making the structure for the volume adjustment assembly to adjust the volume of the adjustment cavity simple and the stability of the adjustment and noise reduction process higher.

Description

Technical Field

[0001] The present invention relates to the technical field of compressors, and particularly to screw compressors. Background Art

[0002] A screw compressor is a high-speed rotating positive displacement compressor. The screw compressor sucks in gas by the rotation of the rotor. The gas accumulates between the rotor and the housing and is compressed as the rotor rotates, and finally discharged. However, since the compression process is completed in a closed space, the high-pressure gas after compression starts to exhaust only when it reaches the discharge chamber. As a result, pressure pulsation occurs at the moment when the compression process ends and is connected to the discharge chamber, and then vibration radiation noise is generated. The traditional screw compressor achieves the purpose of noise reduction by setting a pulsation attenuation device. However, the structure of the traditional pulsation attenuation device is complex, resulting in poor stability of adjusting noise reduction and affecting the normal operation of the screw compressor. Summary of the Invention

[0003] In view of the problem that the structure of the traditional pressure pulsation attenuation device is complex, resulting in poor stability of adjusting noise reduction, the present invention provides a screw compressor, which can achieve the technical effects of reducing the structural complexity and ensuring the stability of adjusting noise reduction.

[0004] A screw compressor, comprising a body, a rotor member, a cam structure and a volume adjustment assembly. A rotor cavity is formed in the body, and a discharge chamber communicating with the rotor cavity is formed on the body. The rotor member is disposed in the rotor cavity and can rotate in the rotor cavity around an axis. The cam structure is disposed on the rotor member, and the rotor member can drive the cam structure to rotate synchronously. A contact convex tooth is disposed on the outer edge of the cam structure. An adjustment cavity is further formed on the body, and the adjustment cavity communicates with the discharge chamber. One end of the volume adjustment assembly penetrates into the adjustment cavity, and the other end can abut against the contact convex tooth on the outer edge of the cam structure. The cam structure is used to drive the volume adjustment assembly to move in the adjustment cavity to adjust the volume of the communication between the adjustment cavity and the discharge chamber.

[0005] In one embodiment, an inter-tooth elementary volume is formed on the rotor member. When the inter-tooth elementary volume communicates with the discharge chamber instantaneously, the contact convex tooth pushes the volume adjustment assembly to move so as to increase the volume of the communication between the adjustment cavity and the discharge chamber.

[0006] In one embodiment, the rotor teeth drive the cam structure to rotate in a first direction. A first tooth surface and a second tooth surface that are in contact with the volume adjustment assembly are formed on a single abutting convex tooth. The first tooth surface and the second tooth surface intersect to form the tooth top line of the abutting convex tooth, and the direction from the second tooth surface to the first tooth surface is the first direction. The moving direction of the volume adjustment assembly in the adjustment cavity is towards the rotation axis of the cam structure. When the tooth interval basic volume is in communication with the discharge cavity instantaneously, the other end of the volume adjustment assembly abuts against the first tooth surface of the abutting convex tooth.

[0007] In one embodiment, a plane formed by the tooth top line of the abutting convex tooth and the rotation axis is used as a reference plane, and the included angle between the first tooth surface and the reference plane is smaller than the included angle between the second tooth surface and the reference plane.

[0008] In one embodiment, the number of the abutting convex teeth is the same as the number of teeth of the rotor member, and each of the abutting convex teeth is uniformly arranged around the rotation axis of the cam structure.

[0009] In one embodiment, the volume adjustment assembly includes a piston body and a piston rod. The piston body is arranged in the adjustment cavity, and the outer wall of the piston body abuts against the inner wall of the adjustment cavity. One end of the piston rod is connected to the piston body, and the other end can abut against the abutting convex tooth on the outer edge of the cam structure. The piston rod can push the piston body to move in the adjustment cavity in a direction towards or away from the cam structure.

[0010] In one embodiment, the volume adjustment assembly further includes a contact wheel. The contact wheel is rotatably arranged at one end of the piston rod away from the piston body, and the contact wheel can abut against the abutting convex tooth on the outer edge of the cam structure.

[0011] In one embodiment, the volume adjustment assembly further includes an elastic member. The elastic member is arranged on the piston body, and the elastic member is used to apply an elastic force towards the cam structure to the piston body; or

[0012] The volume adjustment assembly further includes an elastic member. The elastic member is arranged on the piston rod, and the elastic member is used to apply an elastic force towards the cam structure to the piston rod.

[0013] In one embodiment, a wear-resistant layer is arranged on the inner wall of the adjustment cavity.

[0014] In one embodiment, a communication hole is formed in the inner wall of the adjustment chamber. An intake chamber is further formed in the machine body. The intake chamber communicates with the discharge chamber through the rotor chamber. The adjustment chamber communicates with the intake chamber through the communication hole. The communication hole is located on a side of the volume adjustment assembly facing away from the discharge chamber; or

[0015] A communication hole is formed in the inner wall of the adjustment chamber. The adjustment chamber communicates with the outside through the communication hole. The communication hole is located on a side of the volume adjustment assembly facing away from the discharge chamber.

[0016] In one embodiment, a resonance chamber is formed in the inner wall of the discharge chamber. The resonance chamber is used to attenuate the airflow pulsation entering the discharge chamber.

[0017] In one embodiment, a cavity is formed in the inner wall of the discharge chamber. A cover plate is arranged on the inner wall of the discharge chamber. The cover plate covers the cavity, and a through hole communicating with the cavity is formed in the cover plate. The through hole and the cavity together form the resonance chamber.

[0018] In one embodiment, the rotor member includes a female rotor and a male rotor. The female rotor is arranged in the rotor chamber. The male rotor is arranged in the rotor chamber and meshes with the female rotor to rotate; the cam structure is arranged on the male rotor or the female rotor, and the number of the abutting convex teeth is the same as the number of teeth of the male rotor.

[0019] In the above screw compressor, the rotor member is arranged in the rotor chamber of the machine body. During the rotation of the rotor member, gas can be compressed, and then the compressed gas is discharged into the discharge chamber. Since the cam structure is arranged on the rotor member and the cam structure rotates synchronously with the rotor member, the abutting convex teeth on the cam structure are used to abut against the volume adjustment assembly, so as to realize the adjustment of the communication volume between the adjustment chamber and the discharge chamber. The above screw compressor uses the cooperation of the abutting convex teeth on the cam structure and the volume adjustment assembly, avoiding the use of electronic chips or electronic actuating elements to control the movement of the volume adjustment assembly, without the need to connect an external power supply, nor the need for components that manually or cooperate with other external devices to control the movement of the volume adjustment assembly, making the structure for the volume adjustment assembly to adjust the volume of the adjustment chamber simple and the stability of the adjustment and noise reduction process higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0022] In addition, the accompanying drawings are not drawn to a scale of 1:1, and the relative sizes of the respective components are only drawn exemplarily in the accompanying drawings and not necessarily according to the actual scale. In the accompanying drawings:

[0023] Figure 1 is a schematic diagram of a partial structure of a screw compressor in an embodiment;

[0024] Figure 2 is Figure 1 a cross-sectional view of the shown screw compressor.

[0025] Explanation of reference numerals:

[0026] 10, screw compressor; 100, body; 110, rotor cavity; 120, discharge cavity; 130, adjustment cavity; 140, communication hole; 150, resonance cavity; 152, cavity; 154, cover plate; 156, through hole; 200, rotor member; 210, female rotor; 220, male rotor; 300, cam structure; 310, abutting convex teeth; 312, first tooth surface; 314, second tooth surface; 400, volume adjustment assembly; 410, piston body; 420, piston rod; 430, sealing ring; 440, elastic member; 450, wear-resistant sleeve; 460, abutting wheel. Detailed embodiments

[0027] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following will provide a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings. Many specific details are set forth in the following description to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein. Those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0028] Refer to Figure 1 and Figure 2, the screw compressor 10 in an embodiment of the present invention is used to compress gas. The screw compressor 10 includes a housing 100, a rotor member 200, a cam structure 300, and a volume adjustment assembly 400. A rotor chamber 110 is formed inside the housing 100, and a discharge chamber 120 communicating with the rotor chamber 110 is formed on the housing 100; the rotor member 200 is disposed in the rotor chamber 110 and can rotate in the rotor chamber 110 about an axis; the cam structure 300 is disposed on the rotor member 200, and the rotor member 200 can drive the cam structure 300 to rotate synchronously. An abutting convex tooth 310 is disposed on the outer edge of the cam structure 300; an adjustment chamber 130 is further formed on the housing 100, the adjustment chamber 130 communicates with the discharge chamber 120, one end of the volume adjustment assembly 400 passes through the adjustment chamber 130, and the other end abuts against the abutting convex tooth 310 on the outer edge of the cam structure 300. The cam structure 300 is used to drive the volume adjustment assembly 400 to move in the adjustment chamber 130 to adjust the volume of the adjustment chamber 130 communicating with the discharge chamber 120.

[0029] In the above screw compressor 10, the rotor member 200 is disposed in the rotor chamber 110 of the housing 100. During the rotation of the rotor member 200, gas compression can be achieved, and then the compressed gas is discharged into the discharge chamber 120. Since the cam structure 300 is disposed on the rotor member 200 and the cam structure 300 rotates synchronously with the rotor member 200, the abutting convex tooth 310 on the cam structure 300 abuts against the volume adjustment assembly 400 to realize the adjustment of the volume of the adjustment chamber 130 communicating with the discharge chamber 120. The above screw compressor 10 utilizes the cooperation between the abutting convex tooth 310 on the cam structure 300 and the volume adjustment assembly 400, avoiding the use of electronic chips or electronic actuating elements to control the movement of the volume adjustment assembly 400. There is no need to connect an external power supply, nor is there a need for a component that manually or cooperates with other external devices to control the movement of the volume adjustment assembly 400, making the structure for the volume adjustment assembly 400 to adjust the volume of the adjustment chamber 130 communicating with the discharge chamber 120 simple, and the stability of the adjustment and noise reduction process is higher.

[0030] In one embodiment, the rotor member 200 includes a female rotor 210 and a male rotor 220. The female rotor 210 is disposed in the rotor chamber 110, and the male rotor 220 is disposed in the rotor chamber 110 and meshes with the female rotor 210 to rotate; the cam structure 300 is disposed on the male rotor 220 or the female rotor 210, and the number of the abutting convex teeth 310 is the same as the number of teeth of the convex teeth of the male rotor 220. Gas compression is achieved through the meshing of the male rotor 220 and the female rotor 210.

[0031] In one embodiment, the rotor member 200 is disposed within the rotor cavity 110 and is capable of rotating within the rotor cavity 110 about a rotation axis b. The cam structure 300 rotates about the rotation axis b. Specifically, the cam structure 300 is disposed on the male rotor 220, and the male rotor 220 rotates about the rotation axis b; or the cam structure 300 is disposed on the female rotor 210, and the female rotor 210 rotates about the rotation axis b.

[0032] Specifically, an inter-tooth basic volume is formed between the teeth of the male rotor 220 and the female rotor 210. During the compression process of the screw compressor 10, after the gas enters the inter-tooth basic volume, since the convex teeth of the male rotor 220 continuously invade the concave teeth of the female rotor 210, the inter-tooth basic volume begins to shrink, realizing the gas compression process until the moment when the inter-tooth basic volume is connected to the discharge cavity 120. After the inter-tooth basic volume is connected to the discharge cavity 120, the exhaust process begins and continues until the convex teeth of the male rotor 220 are completely engaged with the concave teeth of the female rotor 210, that is, when the inter-tooth basic volume becomes zero due to the complete engagement of the convex teeth and the concave teeth.

[0033] In other embodiments, the screw compressor 10 may also be a single-screw compressor, or may be other types of screw compressors 10 that can achieve gas compression.

[0034] In one embodiment, the number of the abutting convex teeth 310 is the same as the number of teeth of the rotor member 200, and each of the abutting convex teeth 310 is uniformly arranged around the rotation axis b of the cam structure 300. Specifically, the number of the abutting convex teeth 310 is the same as the number of convex teeth of the male rotor 220, and the convex teeth of the male rotor 220 are uniformly arranged around the rotation axis b. By abutting the abutting convex teeth 310 on the cam structure 300 against the volume adjustment assembly 400, the adjustment of the communication volume between the adjustment cavity 130 and the discharge cavity 120 is realized. Since the number of the abutting convex teeth 310 on the cam structure 300 is the same as the number of teeth of the rotor member 200 and the abutting convex teeth 310 are uniformly arranged, it is convenient to make the variation law of the adjustment of the adjustment cavity 130 by the volume adjustment assembly 400 stable, and it can make the volume change of the adjustment cavity 130 adjusted by the volume adjustment assembly 400 change synchronously with the exhaust frequency of the rotor member 200, adapting to the discharge frequency of the compressed gas.

[0035] In one embodiment, an inter-tooth elementary volume is formed on the rotor member 200. When the inter-tooth elementary volume communicates with the discharge chamber 120 instantaneously, the abutting convex tooth 310 pushes the volume adjustment assembly 400 to move, so that the volume of the communication between the adjustment chamber 130 and the discharge chamber 120 increases. During the rotation of the rotor member 200, the gas is compressed within the inter-tooth elementary volume, and the pressure of the gas continuously increases, which further leads to a pressure difference between the compressed gas and the gas pressure in the discharge chamber 120. When the inter-tooth elementary volume communicates with the discharge chamber 120 instantaneously, the compressed gas enters the discharge chamber 120, and the compressed gas will generate a pulse on the gas in the discharge chamber 120. At this time, the abutting convex tooth 310 is used to push the volume adjustment assembly 400 to move, so that the volume of the communication between the adjustment chamber 130 and the discharge chamber 120 increases, thereby increasing the volume of the discharge chamber 120 for accommodating the compressed gas, generating a certain relative negative pressure, and thus reducing the pulsation pressure amplitude.

[0036] Specifically, the rotor teeth drive the cam structure 300 to rotate in the first direction a. A first tooth surface 312 and a second tooth surface 314 for abutting against the volume adjustment assembly 400 are formed on a single abutting convex tooth 310. The first tooth surface 312 and the second tooth surface 314 intersect to form the tooth top line of the abutting convex tooth 310, and the direction from the second tooth surface 314 to the first tooth surface 312 is the first direction a. The moving direction of the volume adjustment assembly 400 in the adjustment chamber 130 is towards the rotation axis b of the cam structure 300. When the inter-tooth elementary volume communicates with the discharge chamber 120 instantaneously, the other end of the volume adjustment assembly 400 abuts against the first tooth surface 312 of the abutting convex tooth 310. When the inter-tooth elementary volume communicates with the discharge chamber 120 instantaneously, the volume adjustment assembly 400 abuts against the first tooth surface 312 of the abutting convex tooth 310. Since the abutting convex tooth 310 rotates from the second tooth surface 314 towards the first tooth surface 312, the other end of the volume adjustment assembly 400 rotates towards the tooth top line on the first tooth surface 312, so as to push the volume adjustment assembly 400 to move in the adjustment chamber 130 in a direction away from the cam structure 300, thereby realizing an increase in the volume of the communication between the adjustment chamber 130 and the discharge chamber 120.

[0037] In other embodiments, the abutting convex tooth 310 can also be of other structural shapes, and the moving direction of the volume adjustment assembly 400 in the adjustment chamber 130 can also be towards other directions, as long as it can ensure that when the inter-tooth elementary volume communicates with the discharge chamber 120 instantaneously, the communication volume between the adjustment chamber 130 and the discharge chamber 120 increases.

[0038] In one embodiment, a plane formed by the top line of the abutting convex tooth 310 and the rotation axis b of the cam structure 300 is used as a reference plane, and the included angle between the first tooth surface 312 and the reference plane is smaller than the included angle between the second tooth surface 314 and the reference plane. When the gas compression ends and the compressed gas enters the discharge chamber 120 from the tooth space basic volume, the volume adjustment component 400 abuts against the first tooth surface 312. Since the included angle between the first tooth surface 312 and the reference plane is smaller than the included angle between the second tooth surface 314 and the reference plane, the adjustment chamber 130 has the largest volume change rate at this time, and the volume of the discharge chamber 120 increases rapidly, which can rapidly increase the relative negative pressure generated by the volume increase of the discharge chamber 120, weaken the instantaneous pulse pressure of the compressed high-pressure gas communicating with the discharge chamber 120, and achieve the attenuation of the air flow pulsation at the exhaust end. At the same time, since the number of teeth of the abutting convex tooth 310 is the same as that of the rotor member 200, the abutting convex tooth 310 pushes the volume adjustment component 400 to adjust the adjustment chamber 130 to the maximum volume change rate and discharge the compressed gas into the discharge chamber 120 synchronously during the above process. The screw compressor 10 in the above embodiment has an air flow pulsation attenuation effect under all working conditions.

[0039] In one embodiment, a communication hole 140 is formed on the inner wall of the adjustment chamber 130. An intake chamber is further formed in the machine body 100. The intake chamber communicates with the discharge chamber 120 through the rotor chamber 110, and the adjustment chamber 130 communicates with the intake chamber through the communication hole 140. The communication hole 140 is located on the side of the volume adjustment component 400 facing away from the discharge chamber 120. When the volume adjustment component 400 adjusts the communication volume between the adjustment chamber 130 and the discharge chamber 120, the communication hole 140 is used to prevent the space on the side of the volume adjustment component 400 facing away from the discharge chamber 120 from being airtight, which may cause a large resistance to the movement of the volume adjustment component 400 and affect the movement of the volume adjustment component 400 in the adjustment chamber 130. Connecting the space in the adjustment chamber 130 on the side of the volume adjustment component 400 facing away from the discharge chamber 120 to the intake chamber through the communication hole 140 can avoid the resistance caused by compressing the gas in the airtight space, reduce the consumption of useless work of the volume adjustment component 400. At the same time, since the communication hole 140 communicates with the intake chamber, it can prevent external impurities from entering the adjustment chamber 130 and affecting the movement of the volume adjustment component 400 in the adjustment chamber 130. Further, if a small amount of gas leaks from the discharge chamber 120 to the side of the volume adjustment component 400 facing away from the discharge chamber 120, the leaked gas can enter the intake chamber to avoid gas leakage to the outside.

[0040] In another embodiment, the adjustment chamber 130 communicates with the outside through the communication hole 140, and the communication hole 140 is located on a side of the volume adjustment assembly 400 facing away from the discharge chamber 120. This can avoid the resistance caused by compressing the gas in the closed space and reduce the consumption of useless work of the volume adjustment assembly 400.

[0041] Further, the communication hole 140 is opened on the bottom wall of the adjustment chamber 130, or the communication hole 140 is opened at a position of the adjustment chamber 130 away from the discharge chamber 120. This can avoid the influence of the movement of the volume adjustment assembly 400 in the adjustment chamber 130 on the communication between the adjustment chamber 130 and the suction chamber through the communication hole 140.

[0042] In one embodiment, the volume adjustment assembly 400 includes a piston body 410 and a piston rod 420. The piston body 410 is disposed in the adjustment chamber 130, and the outer wall of the piston body 410 abuts against the inner wall of the adjustment chamber 130. One end of the piston rod 420 is connected to the piston body 410, and the other end can abut against the abutting convex teeth 310 on the outer edge of the cam structure 300. The piston rod 420 can push the piston body 410 to move in the adjustment chamber 130 in a direction towards or away from the cam structure 300. The adjustment of the volume of the adjustment chamber 130 is facilitated by the piston body 410, and the movement of the piston body 410 following the rotation of the cam structure 300 is facilitated by the piston rod 420. In this embodiment, one end of the piston rod 420 is connected to the piston body 410 by a thread. In other embodiments, one end of the piston rod 420 can also be hinged to the piston body 410 or directly fixed to the piston body 410.

[0043] Specifically, the volume adjustment assembly 400 further includes a sealing ring 430. The sealing ring 430 is sleeved on the piston body 410 and is located between the piston body 410 and the inner wall of the adjustment chamber 130. By providing the sealing ring 430 on the piston body 410, the sealing performance between the piston body 410 and the inner wall of the adjustment chamber 130 can be further improved, and the gas in the discharge chamber 120 can be prevented from leaking into the adjustment chamber 130 on the side of the piston body 410 facing away from the discharge chamber 120. Further, the sealing ring 430 is made of a wear-resistant material to reduce the wear between the sealing ring 430 and the inner wall of the adjustment chamber 130.

[0044] In this embodiment, there are two sealing rings 430. The two sealing rings 430 are arranged on the piston body 410 at intervals along the moving direction of the piston body 410, so as to further improve the sealing performance between the piston body 410 and the inner wall of the adjustment chamber 130. In other embodiments, the number of the sealing rings 430 can also be one, three or other numbers, as long as the sealing performance between the piston body 410 and the inner wall of the adjustment chamber 130 is ensured.

[0045] In one embodiment, the volume adjustment assembly 400 further includes an elastic member 440. The elastic member 440 is disposed on the piston body 410, and the elastic member 440 is configured to apply an elastic force to the piston body 410 in the direction towards the cam structure 300. By providing the elastic member 440, the stability of the piston rod 420 abutting against the cam structure 300 can be improved, facilitating the piston body 410 driven by the piston rod 420 to change following the abutting convex teeth 310 on the cam structure 300.

[0046] Specifically, the elastic member 440 is disposed in the adjustment cavity 130 and on the side of the piston body 410 opposite to the piston rod 420. One end of the elastic member 440 abuts against the piston body 410, and the other end abuts against the bottom wall of the adjustment cavity 130. This facilitates the elastic member 440 to apply an elastic force to the piston body 410 in the direction towards the cam structure 300.

[0047] In another embodiment, the volume adjustment assembly 400 further includes an elastic member 440. The elastic member 440 is disposed on the piston rod 420, and the elastic member 440 is configured to apply an elastic force to the piston rod 420 in the direction towards the cam structure 300, as long as the stability of the piston rod 420 abutting against the cam structure 300 can be improved by using the elastic member 440.

[0048] In this embodiment, the elastic member 440 is a spring. The spring has a relatively large stiffness coefficient, and its elastic restoring force is sufficient to enable the piston body 410 to overcome the frictional force between the gas pressure in the discharge cavity 120 and the inner wall of the adjustment cavity 130, causing the piston rod 420 to closely adhere to the outer wall of the cam structure 300. In other embodiments, the elastic member 440 can also be other elastic components.

[0049] In one embodiment, a wear-resistant layer is provided on the inner wall of the adjustment cavity 130. Since the piston body 410 moves in the adjustment cavity 130, the wear between the piston body 410 and the inner wall of the adjustment cavity 130 is relatively large. By providing a wear-resistant layer on the inner wall of the adjustment cavity 130, the wear of the piston body 410 on the inner wall of the adjustment cavity 130 can be reduced, thereby ensuring the sealing performance between the piston body 410 and the inner wall of the adjustment cavity 130.

[0050] Specifically, the volume adjustment assembly 400 further includes a wear-resistant sleeve 450. The outer wall of the wear-resistant sleeve 450 is attached to the inner wall of the adjustment cavity 130 to form a wear-resistant layer, and the piston body 410 is disposed within the wear-resistant sleeve 450 and can move within the wear-resistant sleeve 450. In other embodiments, a wear-resistant coating can also be applied on the inner wall of the adjustment cavity 130 to form a wear-resistant layer.

[0051] In one embodiment, the volume adjustment assembly 400 further includes a contact wheel 460 rotatably disposed at one end of the piston rod 420 away from the piston body 410, and the contact wheel 460 can be in contact with the contact convex teeth 310 on the outer edge of the cam structure 300. The use of the contact wheel 460 can reduce the frictional resistance on the cam structure 300, thereby reducing the wear between the piston rod 420 and the cam structure 300.

[0052] In this embodiment, the contact wheel 460 is disposed at one end of the piston rod 420 through a rotating shaft, and the axial direction of the rotating shaft is the same as the direction of the rotation axis b of the cam structure 300, so as to ensure that the contact wheel 460 can rotate following the rotation of the cam structure 300. In another embodiment, a rotating groove may also be provided at one end of the piston rod 420. The contact wheel 460 is a spherical structure and is disposed in the rotating groove and can rotate in the rotating groove. The part of the contact wheel 460 protruding from the rotating groove can be in contact with the cam structure 300.

[0053] In one embodiment, a resonance cavity 150 is provided on the inner wall of the discharge cavity 120, and the resonance cavity 150 is used to attenuate the airflow pulsation entering the discharge cavity 120. By adjusting the volume through the volume adjustment assembly 400, the attenuation effect of the airflow pulsation in all working conditions can be achieved. By further superimposing the resonance of the resonance cavity 150, the attenuation effect can be further improved.

[0054] In this embodiment, a cavity 152 is provided on the inner wall of the discharge cavity 120, a cover plate 154 is provided on the inner wall of the discharge cavity 120, the cover plate 154 covers the cavity 152, and a through hole 156 communicating with the cavity 152 is provided on the cover plate 154. The through hole 156 and the cavity 152 together form the resonance cavity 150;

[0055] Among them, the formula for the target attenuation resonance frequency of the resonance cavity 150 is:

[0056]

[0057] In the formula: C is the speed of sound; P is the perforation rate, and the perforation rate is the ratio of the area of the through hole 156 to the area of the part of the cover plate 154 covering the cavity 152; L is the depth of the cavity 152; t is the thickness of the cover plate 154; d is the diameter of the through hole 156.

[0058] According to the target attenuation resonance frequency, the design dimensions of the specific resonance cavity 150 can be determined.

[0059] In this embodiment, the cover plate 154 is fixed to the inner wall of the discharge chamber 120 by screws. In other embodiments, the cover plate 154 can also be disposed on the inner wall of the discharge chamber 120 by welding, cementing, or integral molding.

[0060] In this embodiment, the resonance chamber 150 is a Helmholtz resonance chamber 150. The cavity 152 communicates with the discharge chamber 120 through a through hole 156 in the cover plate 154. The air column in the neck of the through hole 156 reciprocates like a piston under the action of the acoustic pressure. It has a certain mass of gas and also frictions with the wall of the through hole 156 during movement, consuming a part of the acoustic energy. The gas in the cavity 152 is elastic and can impede the pressure change in the cavity 152 caused by the movement of the gas column in the neck of the through hole 156. In this way, the gas column at the neck of the through hole 156 is like a mass, and the gas in the cavity 152 is like a spring, constituting an elastic vibration system. When the acoustic wave frequency in the discharge chamber 120 is equal to its resonance frequency, it will cause the gas column in the neck of the through hole 156 to resonate. At this time, the vibration displacement of the gas column is the largest, the vibration velocity is the largest, the frictional loss of the wall of the through hole 156 is also the largest, and the consumption of acoustic energy is also the largest, achieving the effect of airflow attenuation.

[0061] In this embodiment, two resonance chambers 150 are formed on the inner wall of the discharge chamber 120, and the resonance frequencies of the two resonance chambers 150 are different and can respectively correspond to the two frequencies with the highest peak values of the airflow pulsation under the rated conditions of the screw compressor 10. In other embodiments, the resonance chamber 150 can also be set according to the airflow pulse frequency of the screw compressor 10 in actual applications.

[0062] For the above screw compressor 10, since the law of change of the volume of the adjustment chamber 130 connected to the discharge chamber 120 adjusted by the abutting convex teeth 310 is the same as the airflow pulsation frequency of the screw compressor 10, the target attenuation frequency achieved by using the adjustment chamber 130 is always the airflow pulsation frequency, and thus the applicable frequency range covers all working conditions, and both fixed-frequency and variable-frequency screw compressors 10 can be used. At the same time, in cooperation with the resonance chamber 150, the pulsation attenuation effect of the resonance chamber 150 is superimposed on the airflow pulsation attenuation effect of the variable volume of the adjustment chamber 130 adjusted by the volume adjustment assembly 400, so that the screw compressor 10 has the best airflow pulsation attenuation effect under the rated conditions.

[0063] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0064] The above-described embodiments merely represent several implementation manners of the present invention. Their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

[0065] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

[0066] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0067] In the present invention, unless otherwise clearly specified and limited, the terms such as "mounted", "connected", "connected to", "fixed" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0068] In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "under" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0069] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are only for illustrative purposes and do not represent the only implementation.

Claims

1. A screw compressor, characterized in that, The screw compressor includes: a housing, a rotor cavity is formed in the housing, and a discharge cavity communicating with the rotor cavity is formed on the housing; a rotor member, the rotor member is disposed in the rotor cavity and can rotate in the rotor cavity about an axis; a cam structure, the cam structure is disposed on the rotor member, and the rotor member can drive the cam structure to rotate synchronously. Contact convex teeth are provided on the outer edge of the cam structure; and a volume adjustment assembly, an adjustment cavity is further formed on the housing, the adjustment cavity communicates with the discharge cavity, one end of the volume adjustment assembly penetrates into the adjustment cavity, and the other end can abut against the contact convex teeth on the outer edge of the cam structure. The cam structure is used to drive the volume adjustment assembly to move in the adjustment cavity to adjust the volume of the communication between the adjustment cavity and the discharge cavity; a tooth interval elementary volume is formed on the rotor member. When the tooth interval elementary volume communicates with the discharge cavity instantaneously, the contact convex teeth push the volume adjustment assembly to move so that the volume of the communication between the adjustment cavity and the discharge cavity increases; the rotor member drives the cam structure to rotate in a first direction. A first tooth surface and a second tooth surface for abutting against the volume adjustment assembly are formed on a single contact convex tooth. The first tooth surface and the second tooth surface intersect to form the tooth top line of the contact convex tooth, and the direction from the second tooth surface to the first tooth surface is the first direction; the moving direction of the volume adjustment assembly in the adjustment cavity is towards the rotation axis of the cam structure. When the tooth interval elementary volume communicates with the discharge cavity instantaneously, the other end of the volume adjustment assembly abuts against the first tooth surface of the contact convex tooth; a communication hole is formed on the inner wall of the adjustment cavity, a suction cavity is further formed in the housing, the suction cavity communicates with the discharge cavity through the rotor cavity, and the adjustment cavity communicates with the suction cavity through the communication hole. The communication hole is located on the side of the volume adjustment assembly facing away from the discharge cavity; or a communication hole is formed on the inner wall of the adjustment cavity, and the adjustment cavity communicates with the outside through the communication hole. The communication hole is located on the side of the volume adjustment assembly facing away from the discharge cavity.

2. The screw compressor according to claim 1, characterized in that, A plane formed by the tooth top line of the contact convex tooth and the rotation axis of the cam structure is used as a reference plane, and the included angle between the first tooth surface and the reference plane is smaller than the included angle between the second tooth surface and the reference plane.

3. The screw compressor according to any one of claims 1-2, characterized in that, The number of the contact convex teeth is the same as the number of teeth of the rotor member, and each of the contact convex teeth is uniformly arranged around the rotation axis of the cam structure.

4. The screw compressor according to any one of claims 1-2, characterized in that, The volume adjustment assembly includes a piston body and a piston rod. The piston body is disposed in the adjustment cavity, and the outer wall of the piston body abuts against the inner wall of the adjustment cavity. One end of the piston rod is connected to the piston body, and the other end can abut against the contact convex teeth on the outer edge of the cam structure. The piston rod can push the piston body to move in the adjustment cavity in a direction towards or away from the cam structure.

5. The screw compressor according to claim 4, characterized in that, The volume adjustment assembly further includes a contact wheel rotatably disposed at one end of the piston rod away from the piston body, and the contact wheel is capable of contacting the contact convex teeth on the outer edge of the cam structure.

6. The screw compressor according to claim 4, wherein, The volume adjustment assembly further includes an elastic member disposed on the piston body, and the elastic member is configured to apply an elastic force to the piston body in the direction towards the cam structure; or The volume adjustment assembly further includes an elastic member disposed on the piston rod, and the elastic member is configured to apply an elastic force to the piston rod in the direction towards the cam structure.

7. The screw compressor according to claim 4, characterized in that, A wear-resistant layer is provided on the inner wall of the adjustment chamber.

8. The screw compressor according to any one of claims 1-2, characterized in that, A resonance chamber is formed on the inner wall of the discharge chamber, and the resonance chamber is configured to attenuate the air flow pulsation entering the discharge chamber.

9. The screw compressor according to claim 8, characterized in that, A cavity is formed on the inner wall of the discharge chamber, and a cover plate is provided on the inner wall of the discharge chamber. The cover plate covers the cavity, and a through hole communicating with the cavity is formed on the cover plate. The through hole and the cavity together form the resonance chamber.

10. The screw compressor according to any one of claims 1-2, characterized in that, The rotor member includes a female rotor and a male rotor. The female rotor is disposed in the rotor chamber, and the male rotor is disposed in the rotor chamber and meshes with the female rotor for rotation. The cam structure is disposed on the male rotor or the female rotor, and the number of the contact convex teeth is the same as the number of teeth of the male rotor.

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