Screw compressor

Abstract

The screw compressor comprises an air filter, a motor and a main machine, the motor comprises a motor shell, a stator fixedly arranged in the motor shell and a rotor rotationally arranged in the stator; the main machine comprises a main machine shell, a male rotor and a female rotor, wherein the male rotor and the female rotor are arranged in the main machine shell and meshed with each other. The air filter is provided with a first air inlet and a first air outlet, the main machine shell is provided with a second air inlet and a second air outlet, the motor shell is further sleeved with a housing, the housing is provided with a third air inlet and a third air outlet, and a first air channel communicated with the third air inlet and the third air outlet is further arranged between the housing and the motor shell. The first air outlet of the air filter is communicated with the third air inlet of the housing, and the third air outlet of the housing is communicated with the second air inlet of the main machine shell. The screw compressor is simple and compact in structure, low in cost and suitable for the outdoor use environment.

Description

Technical Field

[0001] This utility model relates to the field of compressor technology, specifically to a screw compressor. Background Technology

[0002] A screw compressor typically includes an air filter, a motor, and a compressor unit. The motor includes a motor housing, a stator fixed within the motor housing, and a rotor rotatably mounted within the stator. The compressor unit includes a compressor housing and meshing male and female rotors mounted within the compressor housing. The compressor housing has an inlet and an outlet. The air filter is connected to the inlet of the compressor housing and is used to filter dust and impurities entering the compressor unit. The male and female rotors are driven to rotate by the motor, and the high-speed rotation and friction of the motor rotors generate high heat, thus requiring motor cooling. Existing motor cooling solutions generally include oil cooling and air cooling.

[0003] One type of oil-cooling scheme for a screw compressor motor, as disclosed in Chinese invention patent application CN112594186A, utilizes an external oil tank, an oil pump, a first oil heat exchanger, and a second oil heat exchanger. The oil pump is driven by a separate oil pump motor, and both the first and second oil heat exchangers are connected to a fan. During the cooling process, the oil pump pumps lubricating oil from the oil tank, which is then transported along a pipeline through the first and second oil heat exchangers to obtain cooling oil. The cooling oil is then transported through pipelines to the oil-cooling inlet of the motor and returns to the oil tank from the motor's oil-cooling outlet for a new cooling cycle.

[0004] One type of air-cooled motor cooling solution for screw compressors, as disclosed in Chinese Utility Model Patent No. CN204408102U, is achieved by installing a fan inside the motor housing and a rear cover vent plate on the motor housing. The rear cover vent plate draws in low-temperature outside air, which flows and exchanges heat in the gap between the rotor and stator and in the flow channel between the stator and the motor housing. The air after heat exchange is then thrown out of the motor housing by the fan.

[0005] However, existing screw compressors still have the following technical problems: Screw compressors using an oil-cooled motor solution require external installation of an oil tank, oil pump, first oil heat exchanger, and second oil heat exchanger, resulting in a complex and non-compact structure and higher costs; while screw compressors using an air-cooled motor solution, although cost-effective, still require an additional fan inside the motor housing, and also require ventilation holes on the motor housing. The presence of ventilation holes is not conducive to waterproofing and dustproofing, has high requirements for the operating environment, and is not suitable for outdoor use. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a screw compressor with a simple and compact structure, low cost and suitability for outdoor use.

[0007] The technical solution of this utility model is: a screw compressor, including an air filter, a motor, and a main unit; the motor includes a motor housing, a stator fixed in the motor housing, and a rotor rotatably disposed in the stator; the main unit includes a main unit housing, and a male rotor and a female rotor meshing with each other disposed in the main unit housing; the air filter is provided with a first air inlet and a first air outlet, the main unit housing is provided with a second air inlet and a second air outlet, a cover is also provided outside the motor housing, the cover is provided with a third air inlet and a third air outlet, a first air duct connecting the third air inlet and the third air outlet is provided between the cover and the motor housing, the first air outlet of the air filter is connected to the third air inlet of the cover, and the third air outlet of the cover is connected to the second air inlet of the main unit housing.

[0008] The air-cooling process of the screw compressor of this utility model is as follows:

[0009] The male and female rotors inside the main unit operate under the drive of the motor. During the air intake process, the male and female rotors generate a strong negative pressure, which draws in the low-temperature external air into the air filter. The air purified by the air filter is then drawn into the third air inlet of the housing. The low-temperature air entering the third air inlet enters the space between the housing and the motor housing through the first air duct to cool the motor housing and internal components. The air that has exchanged heat with the motor is then discharged through the third air outlet of the housing and continues to be transported to the second air inlet of the main unit housing using negative pressure. The air entering the second air inlet is compressed by the male and female rotors to form compressed air, which is discharged from the second air outlet of the main unit housing.

[0010] With the above structure, this utility model has the following advantages:

[0011] This utility model screw compressor uses an air-cooling scheme to cool the motor, but without the need for a fan. Instead, the intake air and air filter are moved from the front of the main unit to the motor, and the negative pressure generated by the main unit is cleverly used to draw in low-temperature external air, thereby achieving cooling of the motor by the intake air. Then, using the original intake and exhaust structure of the main unit, the intake air that has exchanged heat with the motor is drawn into the main unit for compression and then discharged. The overall solution makes full use of the characteristics of existing devices, mainly by improving the pipeline of the intake section. Therefore, fewer additional parts are required, and the overall structure is relatively simple, compact, and low-cost. In addition, since the entire gas flow is achieved through pipelines and internal air ducts, there is no need to set any vents. In addition, the air filter provides good waterproof and dustproof performance, making it suitable for outdoor use.

[0012] Preferably, the cover is attached to the outer wall of the motor housing. This arrangement not only makes the structure more compact, but also helps to concentrate the air intake and bring it close to the motor housing, thus enabling the motor to dissipate heat more quickly.

[0013] Preferably, the outer wall of the motor housing has at least two annular protrusions along the circumferential direction, and a first air duct is formed between two adjacent annular protrusions. This air duct has a simple structure and can isolate the air intake and exhaust, thereby ensuring that the air entering at the third air intake can flow smoothly to the third air outlet.

[0014] Preferably, both ends of the cover are sealed to the motor housing. This design not only prevents air leakage between the cover and the motor housing, but also provides waterproofing and dustproofing, thus better meeting the requirements for outdoor use.

[0015] Preferably, both the motor housing and the cover are cylindrical. This configuration allows for a smaller and more compact motor structure.

[0016] Preferably, the third air outlet of the cover is connected to the second air inlet of the main unit housing via a flexible hose. This arrangement facilitates the connection between the third air outlet and the second air inlet.

[0017] Preferably, the main housing includes an oil storage chamber and a working chamber. The male and female rotors are installed in the working chamber. The main housing also includes a spindle, one end of which is connected to a motor and the other end to either the male or female rotor. An oil pump is also installed within the main housing and on the spindle. The oil pump's inlet is connected to the oil storage chamber, and its outlet is connected to the oil distribution system within the main housing. When the motor drives the spindle to rotate, the oil pump pumps lubricating oil from the oil storage chamber to the oil distribution system. This design integrates the oil storage chamber and oil pump internally and directly utilizes the spindle to drive the oil pump, resulting in high integration and a simpler, more compact structure.

[0018] Preferably, the oil storage chamber is provided with a second air duct connecting the second air inlet to the air intake area of ​​the working chamber, and the second air outlet is connected to the air outlet area of ​​the working chamber. This arrangement further utilizes the intake air to cool the lubricating oil in the built-in oil storage chamber, thereby eliminating the need for an additional oil cooling device for the oil storage chamber, further simplifying the structure and reducing costs.

[0019] Preferably, the two ends of the male and female rotors are rotatably mounted in the working chamber via an intake bearing assembly and an exhaust bearing assembly, and the output of the oil distribution system is connected to the intake and exhaust bearing assemblies. This arrangement allows for lubrication and cooling of the intake and exhaust bearing assemblies via the oil distribution system.

[0020] Preferably, the spindle is directly connected to the motor rotor. This arrangement allows the main unit and motor to share the same shaft, and the integrated design further simplifies the structure. Attached Figure Description

[0021] Figure 1 This is a front view of the screw compressor of this utility model;

[0022] Figure 2 This is a rear view of the screw compressor of this utility model;

[0023] Figure 3 This is a right view of the screw compressor of this utility model;

[0024] Figure 4 for Figure 3 A sectional view at point AA';

[0025] Figure 5 This is a left view of the screw compressor of this utility model;

[0026] Figure 6 for Figure 5 Cross-sectional view at BB' (male and female rotors are hidden to clearly show the working chamber);

[0027] Figure 7 This is a top view of the screw compressor of this utility model;

[0028] Figure 8 for Figure 7 Sectional view at point CC';

[0029] Figure 9 This is a schematic diagram of the assembly of the motor and the spindle of this utility model;

[0030] Figure 10 This is an axial sectional view of the motor of this utility model;

[0031] In the diagram: 1-Air filter, 2-Motor, 3-Main unit, 4-Motor housing, 5-Stator, 6-Rotor, 7-Main unit housing, 8-Male rotor, 9-Female rotor, 10-Second air inlet, 11-Second air outlet, 12-Cover, 13-Third air inlet, 14-Third air outlet, 15-First air duct, 16-Annular protrusion, 17-Oil storage chamber, 18-Working chamber, 19-First gear assembly, 20-Inlet bearing assembly, 21-Main shaft, 22-Oil pump, 23-Second air duct, 24-Exhaust bearing assembly, 25-First gear cavity, 26-First air inlet, 27-First air outlet, 28-Hose, 29-Second gear cavity, 30-Second gear assembly. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0033] Example:

[0034] like Figure 1-10 As shown, a screw compressor includes an air filter 1, a motor 2, and a main unit 3. The motor 2 includes a motor housing 4, a stator 5 fixed inside the motor housing 4, and a rotor 6 rotatably disposed inside the stator 5. The main unit 3 includes a main unit housing 7, and a male rotor 8 and a female rotor 9 meshing with each other disposed inside the main unit housing 7. The air filter 1 is provided with a first air inlet 26 and a first air outlet 27. The main unit housing 7 is provided with a second air inlet 10 and a second air outlet 11. A cover 12 is also provided outside the motor housing 4. The cover 12 is provided with a third air inlet 13 and a third air outlet 14. A first air duct 15 connecting the third air inlet 13 and the third air outlet 14 is also provided between the cover 12 and the motor housing 4. The first air outlet 27 of the air filter 1 is connected to the third air inlet 13 of the cover 12, and the third air outlet 14 of the cover 12 is connected to the second air inlet 10 of the main unit housing 7.

[0035] In this embodiment, the screw compressor uses an air-cooling scheme to cool the motor 2, but there is no need to install a fan. Instead, the intake air and air filter 1 are moved from the main unit 3 to the motor 2. The negative pressure generated by the main unit 3 is cleverly used to draw in low-temperature external air, thereby achieving cooling of the motor 2 by the intake air. Then, the intake air after heat exchange with the motor 2 is drawn into the main unit 3 for compression and discharge using the original intake and exhaust structure of the main unit 3. The overall scheme makes full use of the characteristics of the existing device, mainly by improving the pipeline of the intake section. Therefore, fewer additional parts are required, and the overall structure is relatively simple, compact, and low-cost. In addition, since the entire gas flow is achieved through the pipeline and internal air duct, there is no need to install any vents. In addition, the installation of the air filter 1 provides good waterproof and dustproof performance, making it suitable for outdoor use.

[0036] The cover 12 is attached to the outer wall of the motor housing 4. This arrangement not only makes the structure more compact, but also helps to concentrate the air intake and bring it close to the motor housing 4, thus enabling the motor 2 to dissipate heat more quickly.

[0037] At least two annular protrusions 16 are provided on the outer side wall of the motor housing 4 along the circumferential direction, and a first air duct 15 is formed between two adjacent annular protrusions 16. This air duct has a simple structure and can achieve isolation between air intake and exhaust, thereby ensuring that the air entering at the third air intake 13 can flow smoothly to the third air outlet 14.

[0038] The two ends of the cover 12 are sealed to the motor housing 4. This design not only prevents air leakage between the cover 12 and the motor housing 4, but also helps to prevent water and dust, thus better meeting the requirements for outdoor use.

[0039] Both the motor housing 4 and the cover 12 are cylindrical. This design allows the motor 2 to have a smaller and more compact structure.

[0040] The third air outlet 14 of the cover 12 is connected to the second air inlet 10 of the main unit housing 7 via a hose 28. This arrangement facilitates the connection between the third air outlet 14 and the second air inlet 10.

[0041] The main housing 7 includes an oil storage chamber 17 and a working chamber 18. A male rotor 8 and a female rotor 9 are installed in the working chamber 18. The main housing 7 also includes a main shaft 21, one end of which is connected to a motor 2, and the other end to either the male rotor 8 or the female rotor 9. An oil pump 22 is also installed inside the main housing 7 and on the main shaft 21. The oil inlet of the oil pump 22 is connected to the oil storage chamber 17, and the oil outlet of the oil pump 22 is connected to the oil distribution system inside the main housing 7. When the motor 2 drives the main shaft 21 to rotate, the oil pump 22 pumps lubricating oil from the oil storage chamber 17 to supply the oil distribution system. The main shaft 21 is connected to a driving rotor, and the other is a driven rotor. After the main shaft 21 drives the driving rotor to rotate, the driving rotor then drives the driven rotor to rotate. The connection structure between the main shaft 21, the male rotor 8, and the female rotor 9 can be achieved using existing technology. This design integrates the oil storage chamber 17 and the oil pump 22 internally, and directly utilizes the main shaft 21 to drive the oil pump 22, resulting in high integration and a simpler, more compact structure.

[0042] The oil storage chamber 17 is provided with a second air duct 23 that connects the second air inlet 10 to the air intake area of ​​the working chamber 18, and the second air outlet 11 is connected to the air outlet area of ​​the working chamber 18. This arrangement further utilizes the intake air to cool the lubricating oil in the built-in oil storage chamber 17, thereby eliminating the need for an additional oil cooling device for the oil storage chamber 17, further simplifying the structure and reducing costs.

[0043] The male rotor 8 and female rotor 9 are rotatably mounted in the working chamber 18 via the inlet bearing assembly 20 and the exhaust bearing assembly 24. The output of the oil distribution system is connected to the inlet bearing assembly 20 and the exhaust bearing assembly 24, which can be constructed using existing technology. This setup allows for lubrication and cooling of the inlet bearing assembly 20 and the exhaust bearing assembly 24 via the oil distribution system.

[0044] A first gear cavity 25 is provided inside the main housing 7 and on the side of the working chamber 18 near the intake bearing assembly 20. The motor 2 is located on the side of the main housing 7 near the intake bearing assembly 20. The first gear cavity 25 contains a first gear assembly 19 that connects the main shaft 21 to the male rotor 8 or female rotor 9. The output of the oil distribution system is also connected to the first gear assembly 19. The first gear assembly 19 can be made using existing technology. This setup allows the first gear assembly 19 to be lubricated and cooled by the oil distribution system.

[0045] A second gear cavity 29 is provided inside the main housing 7 and on the side of the working chamber 18 near the exhaust end bearing assembly 24. The second gear cavity 29 houses a second gear assembly 30 that connects the male rotor 8 and the female rotor 9 to enable synchronous rotation. The output of the oil distribution system is also connected to the second gear assembly 30. The second gear assembly 30 can be manufactured using existing technology. This configuration allows for lubrication and cooling of the second gear assembly 30 via the oil distribution system.

[0046] The main shaft 21 is directly connected to the rotor 6 of the motor 2. This arrangement allows the main unit 3 and the motor 2 to share the same shaft, and the integrated design further simplifies the structure.

[0047] The air-cooling process of the screw compressor in this embodiment is as follows:

[0048] Motor 2 drives the main shaft 21 of the main unit 3 to rotate. The rotation of the main shaft 21 drives the male rotor 8 and female rotor 9 to rotate. During the air intake process, the male rotor 8 and female rotor 9 generate a strong negative pressure, which draws in the low-temperature external air into the air filter 1. The air purified by the air filter 1 is then drawn into the third air inlet 13 of the housing 12. The low-temperature air entering the third air inlet 13 enters the space between the housing 12 and the motor housing 4 through the first air duct 15 to cool the motor housing 4 and its internal components. The air that has exchanged heat with the motor 2 is then discharged through the third air outlet 14 of the housing 12 and continues to be transported to the second air inlet 10 of the main unit housing 7 using negative pressure. The air entering the second air inlet 10 then passes through the first air duct 15 to cool the motor housing 4 and its internal components. The second air duct 23 cools the lubricating oil in the oil storage chamber 17. The cooled lubricating oil is pumped out by the oil pump 22 and lubricated and cooled by the oil distribution system for the intake bearing assembly 20, the exhaust bearing assembly 24, the first gear assembly 19, and the second gear assembly 30. The air that has exchanged heat with the oil storage chamber 17 is then compressed by the male rotor 8 and the female rotor 9 to form compressed air that is discharged from the second air outlet 11 of the main housing 7. Therefore, this air-cooling scheme not only uses the intake air to cool the motor 2, but also uses the intake air to cool the lubricating oil in the built-in oil storage chamber 17. Furthermore, the built-in oil pump 22 is mounted on the main shaft 21 and is directly driven by the main shaft 21, eliminating the need for a drive device for the oil pump 22 and making the structure simpler and more compact.

Claims

1. A screw compressor, comprising an air filter (1), a motor (2), and a main unit (3); the motor (2) comprising a motor housing (4), a stator (5) fixedly disposed within the motor housing (4), and a rotor (6) rotatably disposed within the stator (5); the main unit (3) comprising a main unit housing (7), and a male rotor (8) and a female rotor (9) meshing with each other disposed within the main unit housing (7); the air filter (1) having a first air inlet (26) and a first air outlet (27), and the main unit housing (7) having a second air inlet (10) and a second air outlet (11), characterized in that: The motor housing (4) is also fitted with a cover (12). The cover (12) is provided with a third air inlet (13) and a third air outlet (14). A first air duct (15) connecting the third air inlet (13) and the third air outlet (14) is also provided between the cover (12) and the motor housing (4). The first air outlet (27) of the air filter (1) is connected to the third air inlet (13) of the cover (12). The third air outlet (14) of the cover (12) is connected to the second air inlet (10) of the main unit housing (7).

2. A screw compressor according to claim 1, characterized in that: The cover (12) is attached to the outer wall of the motor housing (4).

3. A screw compressor according to claim 2, characterized in that: At least two annular protrusions (16) are provided on the outer side wall of the motor housing (4) in the circumferential direction, and a first air duct (15) is formed between two adjacent annular protrusions (16).

4. A screw compressor according to claim 1, characterized in that: The two ends of the cover (12) are sealed to the motor housing (4).

5. A screw compressor according to claim 1, characterized in that: Both the motor housing (4) and the cover (12) are cylindrical.

6. A screw compressor according to claim 1, characterized in that: The third air outlet (14) of the cover (12) is connected to the second air inlet (10) of the main housing (7) through a hose (28).

7. A screw compressor according to claim 1, characterized in that: The main housing (7) is provided with an oil storage chamber (17) and a working chamber (18). The male rotor (8) and female rotor (9) are installed in the working chamber (18). It also includes a main shaft (21). One end of the main shaft (21) is connected to the motor (2) and the other end is connected to the male rotor (8) or the female rotor (9). An oil pump (22) is also provided in the main housing (7) and on the main shaft (21). The oil inlet of the oil pump (22) is connected to the oil storage chamber (17), and the oil outlet of the oil pump (22) is connected to the oil distribution system in the main housing (7). When the motor (2) drives the main shaft (21) to rotate, the oil pump (22) pumps out the lubricating oil in the oil storage chamber (17) to provide it to the oil distribution system.

8. A screw compressor according to claim 7, characterized in that: The oil storage chamber (17) is provided with a second air duct (23) that connects the second air inlet (10) and the air inlet area of ​​the working chamber (18), and the second air outlet (11) is connected to the air outlet area of ​​the working chamber (18).

9. A screw compressor according to claim 7, characterized in that: The two ends of the male rotor (8) and female rotor (9) are rotatably mounted in the working chamber (18) through the intake bearing assembly (20) and the exhaust bearing assembly (24), and the output of the oil distribution system is connected to the intake bearing assembly (20) and the exhaust bearing assembly (24).

10. A screw compressor according to claim 7, characterized in that: The main shaft (21) is directly connected to the rotor (6) of the motor (2).

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