Screw compressor

Abstract

The utility model discloses a screw compressor, and belongs to the technical field of compressors, the screw compressor comprises a main body, the main body comprises a first shell and a second shell, the first shell is arranged around the second shell, and an airflow channel surrounding the second shell is formed between the first shell and the second shell; the second shell is provided with a compression cavity and a connecting port communicated with the compression cavity, and the connecting port is communicated with the airflow channel; the main body further comprises an air inlet part communicated with the compression cavity and the airflow channel, and the air inlet part is used for inputting air; wherein the air flow channel between the first shell and the second shell can play a certain role in sound insulation, meanwhile, air enters the compression cavity and the air flow channel through the air inlet part, and due to the fact that the flow speed of the air in the air flow channel is smaller than that of the air in the compression cavity, noise transmission in the compression cavity can be restrained to a certain extent; therefore, noise is reduced.

Description

Technical Field

[0001] The present application belongs to the technical field of compressors, and in particular relates to a screw compressor. Background Art

[0002] The active rotor of the screw compressor has convex teeth outside the pitch circle, and the driven rotor has concave teeth inside the pitch circle; if the teeth of the male rotor are regarded as pistons, and the tooth grooves of the female rotor are regarded as cylinders (the tooth grooves, the cylindrical surface and the end wall surface of the body together constitute the working volume called the unit volume), this is just like the working process of a piston compressor. As a pair of screws rotate and mesh, the unit volume of the rotor changes due to the successive intrusion of the female and male rotors. At present, the male and female rotors in the screw compressor will compress the gas when they rotate, causing vibration and making a loud noise. Utility Model Content

[0003] Purpose of the utility model: The embodiment of the present application provides a screw compressor, which aims to overcome the technical problem that the current compressor emits a lot of noise when working.

[0004] Technical solution: A screw compressor described in an embodiment of the present application includes:

[0005] A main body, the main body comprising a first shell and a second shell, the first shell being arranged around the second shell, an air flow channel surrounding the second shell being formed between the first shell and the second shell, the second shell having a compression chamber and a connecting port communicating with the compression chamber, the connecting port being communicated with the air flow channel; the main body further comprising an air inlet connecting the compression chamber and the air flow channel, the air inlet being used to input gas;

[0006] The rotating assembly comprises a first rotor and a second rotor which are meshed with each other. The first rotor and the second rotor are both rotatably connected to the main body and penetrate the compression chamber.

[0007] In some embodiments, the body further comprises:

[0008] A plurality of connectors are arranged at intervals in the air flow channel and are used to connect the first shell and the second shell.

[0009] In some embodiments, the first rotor includes a plurality of first teeth, the second rotor includes a plurality of second teeth, the plurality of first teeth and the plurality of second teeth are both located in the compression chamber, at least some of the first teeth and at least some of the second teeth are meshed with each other, the number of the plurality of first teeth is A, and the number of the plurality of second teeth is B, wherein the smaller number between A and B is a multiple of three.

[0010] In some embodiments, A and B satisfy: A:B=3:5.

[0011] In some embodiments, A and B satisfy: A:B=3:4.

[0012] In some embodiments, A and B satisfy: A:B=3:3.

[0013] In some embodiments, the first teeth and the second teeth are both provided with a coating.

[0014] In some embodiments, the first housing has a flow cavity communicating with the compression cavity and the air flow channel, and the air inlet portion includes:

[0015] An air inlet pipe is connected to the first shell, and the air inlet pipe has an air inlet communicated with the flow cavity, and the air inlet is used to let the gas in.

[0016] In some embodiments, the airflow channel includes a second communicating port, which is used to connect the airflow channel with the circulation chamber; the compression chamber includes a first communicating port, which is used to connect the compression chamber with the circulation chamber.

[0017] In some embodiments, the first shell has a flow chamber communicating with the compression chamber.

[0018] In some embodiments, the main body further comprises an air outlet, and the air outlet comprises:

[0019] An air outlet pipe is connected to the first shell, and the air outlet pipe has an air outlet communicated with the flow chamber, and the air outlet is used to output the gas.

[0020] In some embodiments, the flow chamber has a first flow port and a second flow port, and the first flow port and the second flow port are both connected to the compression chamber and the air outlet.

[0021] Beneficial effect: The screw compressor of the embodiment of the present application includes: a main body, the main body includes a first shell and a second shell, the first shell is arranged around the second shell, an air flow channel surrounding the second shell is formed between the first shell and the second shell, the second shell has a compression chamber and a connecting port connected to the compression chamber, the connecting port is connected to the air flow channel; the main body also includes an air intake part connecting the compression chamber and the air flow channel, the air intake part is used to input gas; a rotating assembly, the rotating assembly includes a first rotor and a second rotor arranged in meshing, the first rotor and the second rotor are both rotatably connected to the main body and pass through the compression chamber; wherein the air flow channel between the first shell and the second shell can play a certain sound insulation role, and at the same time, the gas enters the compression chamber and the air flow channel respectively through the air intake part. Since the flow velocity of the gas in the air flow channel is less than the flow velocity in the compression chamber, the noise transmission in the compression chamber can be inhibited to a certain extent, thereby reducing the noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 It is a front view cross-sectional structural schematic diagram of a screw compressor according to an embodiment of the present application;

[0024] Figure 2 It is a schematic diagram of a side cross-sectional structure of a screw compressor according to an embodiment of the present application;

[0025] Figure 3 This is a schematic diagram of the meshing structure of the first tooth and the second tooth in the first embodiment of the present application;

[0026] Figure 4 This is a schematic diagram of the meshing structure between the first tooth and the second tooth in the second embodiment of the present application;

[0027] Figure 5 This is a schematic diagram of the meshing structure of the first tooth and the second tooth in the third embodiment of the present application;

[0028] Figure markings: 10-main body; 11-first shell; 111-circulation chamber; 112-flow chamber; 1121-first flow port; 1122-second flow port; 12-second shell; 121-compression chamber; 1211-first connecting port; 122-connecting port; 13-air flow channel; 131-second connecting port; 14-inlet part; 141-inlet pipe; 1411-inlet port; 15-outlet part; 151-outlet pipe; 1511-outlet port; 16-connecting piece; 20-rotating assembly; 21-first rotor; 211-first tooth; 22-second rotor; 221-second tooth. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0030] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "plurality" means two or more, and at least one means one, two or more, unless otherwise clearly and specifically defined.

[0031] The active rotor of the screw compressor has convex teeth outside the pitch circle, and the driven rotor has concave teeth inside the pitch circle; if the teeth of the male rotor are regarded as pistons, and the tooth grooves of the female rotor are regarded as cylinders (the tooth grooves, the cylindrical surface in the body, and the end wall surface together constitute the working volume called the unit volume), this is just like the working process of a piston compressor. As a pair of screws rotate and mesh, the unit volume of the rotor changes due to the successive invasion of the female and male rotors. At present, when the male and female rotors in the screw compressor rotate, they compress the gas, causing vibration and making a lot of noise. At the same time, in order to meet the medium-pressure working conditions, the screw compressor adopts the general 4-6 teeth, that is, 4 teeth are installed on the female rotor and 6 teeth are installed on the male rotor. However, this number of teeth setting exposes the disadvantage of low efficiency under low-pressure working conditions.

[0032] In view of this, an embodiment of the present application provides a screw compressor to overcome at least one of the above-mentioned technical problems.

[0033] See also Figure 1 and Figure 2In the embodiment of the present application, the screw compressor includes: a main body 10 and a rotating assembly 20. The main body 10 includes a first shell 11 and a second shell 12. The first shell 11 is arranged around the second shell 12. An air flow channel 13 surrounding the second shell 12 is formed between the first shell 11 and the second shell 12. The second shell 12 has a compression chamber 121 and a connecting port 122 connected to the compression chamber 121. The connecting port 122 is connected to the air flow channel 13. The compression work of the compressor is mainly carried out inside the compression chamber 121, so that the inside of the compression chamber 121 generates greater vibration and noise, and the air flow channel 13 formed between the first shell 11 and the second shell 12 can play a certain role in sound insulation, thereby reducing noise; the main body 10 also includes an air intake portion 14 connecting the compression chamber 121 and the air flow channel 13. The air intake portion 14 is used to input gas, that is, the gas can enter the air flow through the air intake portion 14 respectively. Channel 13 and compression chamber 121, and the gas flowing in the airflow channel 13 can enter the compression chamber 121 through the connecting port 122 and be compressed; the rotating assembly 20 includes a first rotor 21 and a second rotor 22 that are meshed, and the first rotor 21 and the second rotor 22 are both rotatably connected to the main body 10 and pass through the compression chamber 121; specifically, the gas enters the compression chamber 121 and the airflow channel 13 respectively through the air inlet 14, and after part of the gas enters the compression chamber 121, it is squeezed by the compression structure inside the compression chamber 121, forced to flow, with fast speed, strong pulsation, and loud noise, while the gas flow rate of the airflow channel 13 is relatively slow, so the gas flow rate in the airflow channel 13 is less than the flow rate in the compression chamber 121, which can play a certain inhibitory effect on noise transmission, thereby reducing noise.

[0034] See also Figure 2 In some embodiments, the main body 10 further includes a plurality of connectors 16, which are spaced apart in the airflow channel 13 for connecting the first shell 11 and the second shell 12; specifically, the connector 16 may be a metal component having high strength for fixing and supporting the second shell 12, and is located in the airflow channel 13 but does not affect the circulation of gas in the airflow channel 13.

[0035] See also Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5In some embodiments, the first rotor 21 includes a plurality of first teeth 211, and the second rotor 22 includes a plurality of second teeth 221. The plurality of first teeth 211 and the plurality of second teeth 221 are both located in the compression chamber 121, and at least some of the first teeth 211 and at least some of the second teeth 221 are meshed with each other. When the first rotor 21 and the second rotor 22 rotate, some of the corresponding first teeth 211 and some of the corresponding second teeth 221 are meshed with each other, thereby compressing the gas in the compression chamber 121, so that the compressed gas has a higher flow rate. The number of the plurality of first teeth 211 is A, and the number of the plurality of second teeth 221 is B, wherein the smaller number between A and B is a multiple of three.

[0036] See also Figure 3 In some embodiments, A and B satisfy: A:B=3:5; that is, the number of the first teeth 211 is 3, and the number of the second teeth 221 is 5.

[0037] See also Figure 4 In some embodiments, A and B satisfy: A:B=3:4; that is, the number of the first teeth 211 is 3, and the number of the second teeth 221 is 4.

[0038] See also Figure 5 In some embodiments, A and B satisfy: A:B=3:3; that is, the number of the first teeth 211 is 3, and the number of the second teeth 221 is also 3.

[0039] See also Figure 3 , Figure 4 and Figure 5 In summary, in order to meet the medium pressure working condition, the existing screw compressors mostly use the general 4-6 teeth, that is, the number of the first teeth 211 is 4, and the number of the second teeth 221 is 6. However, under the low pressure working condition, it will expose the disadvantages of low efficiency and too expensive equipment for processing the same gas volume. Therefore, a low number of teeth: 3-3 teeth, 3-4 teeth or 3-5 teeth SRMD asymmetric pure arc rotor tooth shape, low torsion angle and large aspect ratio design are adopted, so that the screw compressor can meet the gas boosting requirements of exhaust pressure ≤1.0Mpa and pressure ratio ≤5.0, which greatly increases the large flow rate. In the application scenario of screw compressors under low pressure, the compressor completes the cycle of gas absorption-compression-exhaustion through a closed volume formed by the periodic change of a pair of rotor meshing motion; the gear ratio is 3:3 or 3:4 or 3:5, which can reduce the root diameter, increase the area utilization coefficient, and increase the suction volume compared with conventional 4:6 gear compressors; the low rotor torsion angle (≤240°) is adopted to adapt to the small number of teeth and low compression ratio (≤5.0), ensuring the operating efficiency under low pressure conditions; the large aspect ratio lead design (≥1.8) is adopted to achieve the improvement of the gas processing capacity of the same model;

[0040] The design data is as follows:

[0041] When the ratio of the number of the first teeth 211 to the second teeth 221 is 4:6, the aspect ratio is 1.65, and the area utilization coefficient is 0.5;

[0042] When the ratio of the number of the first teeth 211 to the second teeth 221 is 3:5, the aspect ratio is 1.8, the area utilization coefficient is 0.58, and the theoretical gas volume is increased by 26.5% compared with 4-6 teeth;

[0043] When the ratio of the number of the first teeth 211 to the second teeth 221 is 3:4, the aspect ratio is 1.8, the area utilization coefficient is 0.63, and the theoretical gas volume is increased by 37.5% compared with 4-6 teeth;

[0044] When the ratio of the number of the first teeth 211 to the second teeth 221 is 3:3, the aspect ratio is 1.8, the area utilization coefficient is 0.8, and the theoretical gas volume is increased by 74.5% compared with 4-6 teeth;

[0045] It can be seen that under low pressure conditions, when the gear ratio of the first teeth 211 and the second teeth 221 is 3:3 or 3:4 or 3:5, more gas can be compressed and processed compared to a compressor with 4:6 teeth.

[0046] See also Figure 1 In some embodiments, the plurality of first teeth 211 and the plurality of second teeth 221 are provided with a coating, and the coating may be a rubber coating with a thickness of 0.8 mm. The coating may facilitate the processing of the first rotor 21 and the second rotor 22 and control the meshing clearance between the first rotor 21 and the second rotor 22, and may improve the air tightness during compression of the gas.

[0047] See also Figure 1 In some embodiments, the first shell 11 has a circulation chamber 111 connected to the compression chamber 121 and the air flow channel 13, and the air intake part 14 includes an air intake pipe 141, the air intake pipe 141 is connected to the first shell 11, and the air intake pipe 141 has an air inlet 1411 connected to the circulation chamber 111, and the air inlet 1411 is used to introduce gas; specifically, the gas can enter the circulation chamber 111 inside the device through the air inlet 1411 on the air intake pipe 141, and since the circulation chamber 111 is connected to the compression chamber 121 and the air flow channel 13, the gas can enter the compression chamber 121 and the air flow channel 13 respectively.

[0048] See also Figure 1In some embodiments, the airflow channel 13 includes a second connecting port 131, which is used to connect the airflow channel 13 with the circulation chamber 111; the compression chamber 121 includes a first connecting port 1211, which is used to connect the compression chamber 121 with the circulation chamber 111; specifically, the second connecting port 131 is used to connect the circulation chamber 111 with the airflow channel 13, so that the gas in the circulation chamber 111 can enter the airflow channel 13 through the second connecting port 131, and the first connecting port 1211 is used to connect the circulation chamber 111 with the compression chamber 121, so that the gas in the circulation chamber 111 can enter the compression chamber 121 through the first connecting port 1211.

[0049] See also Figure 1 In some embodiments, the first shell 11 has a flow chamber 112 connected to the compression chamber 121 , so that the gas compressed in the compression chamber 121 can be discharged through the flow chamber 112 .

[0050] See also Figure 1 In some embodiments, the main body 10 also includes an air outlet portion 15, the air outlet portion 15 includes an air outlet pipe 151, the air outlet pipe 151 is connected to the first shell 11, the air outlet pipe 151 has an air outlet 1511 connected to the flow chamber 112, and the air outlet 1511 is used to output gas; specifically, the flow chamber 112 is used to connect the compression chamber 121 with the air outlet 1511, so that the gas entering the flow chamber 112 from the compression chamber 121 can be discharged through the air outlet 1511 on the air outlet pipe 151.

[0051] See also Figure 1 In some embodiments, the flow chamber 112 has a first flow port 1121 and a second flow port 1122, and the first flow port 1121 and the second flow port 1122 are both connected to the compression chamber 121 and the air outlet 1511; specifically, the axially flowing gas inside the compression chamber 121 can enter the air outlet 1511 through the first flow port 1121, and the radially flowing gas inside the compression chamber 121 can enter the air outlet 1511 through the second flow port 1122. Through the first flow port 1121 and the second flow port 1122, two gases with different flow directions can be quickly discharged, thereby improving the gas discharge efficiency.

[0052] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0053] The screw compressor provided in the embodiments of the present application is introduced in detail above, and the principles and implementation methods of the present application are explained by using specific examples. The description of the above embodiments is only used to help understand the technical solution and its core idea of ​​the present application; ordinary technicians in this field should understand that: they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application.

Claims

1. A screw compressor, characterized in that: include: A main body (10), the main body (10) comprising a first shell (11) and a second shell (12), the first shell (11) being arranged around the second shell (12), an air flow channel (13) surrounding the second shell (12) being formed between the first shell (11) and the second shell (12), the second shell (12) having a compression chamber (121) and a connecting port (122) communicating with the compression chamber (121), the connecting port (122) being communicated with the air flow channel (13); the main body (10) further comprising an air inlet (14) communicating with the compression chamber (121) and the air flow channel (13), the air inlet (14) being used for inputting gas; A rotating assembly (20), the rotating assembly (20) comprising a first rotor (21) and a second rotor (22) which are meshed with each other, the first rotor (21) and the second rotor (22) being both rotationally connected to the main body (10) and passing through the compression chamber (121).

2. The screw compressor according to claim 1, characterized in that: The main body (10) further comprises: A plurality of connecting members (16) are arranged at intervals in the air flow channel (13) and are used to connect the first shell (11) and the second shell (12).

3. The screw compressor according to claim 1, characterized in that: The first rotor (21) comprises a plurality of first teeth (211), and the second rotor (22) comprises a plurality of second teeth (221). The plurality of first teeth (211) and the plurality of second teeth (221) are both located in the compression chamber (121), and at least part of the first teeth (211) and at least part of the second teeth (221) are meshed with each other. The number of the plurality of first teeth (211) is A, and the number of the plurality of second teeth (221) is B, wherein the smaller number between A and B is a multiple of three.

4. The screw compressor according to claim 3, characterized in that: A and B satisfy: A:B=3:

5.

5. The screw compressor according to claim 3, characterized in that: A and B satisfy: A:B=3:

4.

6. The screw compressor according to claim 3, characterized in that: A and B satisfy: A:B=3:

3.

7. The screw compressor according to claim 3, characterized in that: The plurality of first teeth (211) and the plurality of second teeth (221) are both provided with a coating.

8. The screw compressor according to claim 1, characterized in that: The first shell (11) has a flow chamber (111) communicating with the compression chamber (121) and the air flow channel (13), and the air inlet portion (14) comprises: An air intake pipe (141), the air intake pipe (141) is connected to the first shell (11), the air intake pipe (141) has an air intake port (1411) connected to the flow chamber (111), and the air intake port (1411) is used to allow the gas to enter.

9. The screw compressor according to claim 8, characterized in that: The airflow channel (13) comprises a second connecting port (131), and the second connecting port (131) is used to connect the airflow channel (13) with the circulation chamber (111); the compression chamber (121) comprises a first connecting port (1211), and the first connecting port (1211) is used to connect the compression chamber (121) with the circulation chamber (111).

10. The screw compressor according to claim 1, characterized in that: The first shell (11) has a flow chamber (112) communicating with the compression chamber (121).

11. The screw compressor according to claim 10, characterized in that: The main body (10) further comprises an air outlet portion (15), wherein the air outlet portion (15) comprises: An air outlet pipe (151), the air outlet pipe (151) is connected to the first shell (11), the air outlet pipe (151) has an air outlet (1511) connected to the flow chamber (112), and the air outlet (1511) is used to output the gas.

12. The screw compressor according to claim 11, characterized in that: The flow chamber (112) has a first flow port (1121) and a second flow port (1122), and the first flow port (1121) and the second flow port (1122) are both connected to the compression chamber (121) and the air outlet (1511).

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