A dual-cooling structure for a permanent magnet synchronous motor in an air compressor

Abstract

This invention provides a dual-cooling structure for a permanent magnet synchronous motor used in air compressors, including a motor housing, an integrated inner housing and rear end cover, cooling water channels between the motor housing and the inner housing, a front end cover, a sealing structure between the front and rear end covers, a motor shaft, cooling water channels within the motor shaft, and an axial fan mounted on the motor shaft. The front and rear end covers of the motor have inlet and outlet ports for the shaft cooling water channels, as well as a safety port. This invention utilizes the circulation of coolant and forced airflow to cool the entire motor, preventing overheating and avoiding reduced efficiency or even demagnetization due to excessive temperature during operation, thus ensuring the stability of motor performance.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a dual-cooling structure for a permanent magnet synchronous motor for an air compressor. Background Technology

[0002] Permanent magnet synchronous motors are widely used in air compressors due to their high power density, high mechanical efficiency, and strong control system stability. However, their compact structure makes natural heat dissipation insufficient to address temperature rise issues. Excessive motor temperature directly impacts efficiency, potentially shortening winding insulation life and causing demagnetization of the permanent magnets. Therefore, a well-designed cooling system is crucial for the motor's performance and must be a primary focus of research.

[0003] Currently, most permanent magnet synchronous motors used in air compressor drives employ water or oil cooling to cool the motor housing and reduce internal temperature rise. Traditional cooling structures, due to their shape and arrangement, impose certain requirements on the driving force of the coolant. Furthermore, their location within the motor prevents them from directly cooling the permanent magnets effectively. Additionally, their cooling structures hinder heat exchange between the internal and external air, further reducing the cooling efficiency. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a dual-cooling structure for a permanent magnet synchronous motor for an air compressor, so as to solve the problems of high requirements for coolant driving force, poor heat dissipation effect of permanent magnet, and difficulty in air convection inside and outside the water-cooled motor.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a dual cooling structure for a permanent magnet synchronous motor for an air compressor, comprising a motor housing (16), an integrated motor inner housing-rear end cover assembly (18), a housing water channel (20) located between the motor housing and the integrated motor inner housing-rear end cover assembly, a motor front end cover (08), a motor shaft (09), a shaft water channel (21) located in the motor shaft, an axial flow fan (05) located on the motor shaft, and a permanent magnet synchronous motor stator / rotor assembly (17).

[0006] The main body of the shaft water channel (21) located in the motor shaft (09) is composed of six axially arranged cylindrical water channels. The cylindrical water channel is composed of a first straight cylindrical water channel (2101), a second straight cylindrical water channel (2102), a third straight cylindrical water channel (2103), a fourth straight cylindrical water channel (2104), a fifth straight cylindrical water channel (2105), and a sixth straight cylindrical water channel (2106). The first straight cylindrical water channel (2101), the second straight cylindrical water channel (2102), the third straight cylindrical water channel (2103), the fourth straight cylindrical water channel (2104), the fifth straight cylindrical water channel (2105), and the sixth straight cylindrical water channel (2106) are arranged in a circular array. The center of the circular array is located at the center of the shaft. The circular array arrangement reduces the non-uniformity caused by rotational motion during operation.

[0007] The rotating shaft waterway (21) is connected near the water outlet by a circular waterway (2107) to the first straight waterway (2101), the second straight waterway (2102), the third straight waterway (2103), the fourth straight waterway (2104), the fifth straight waterway (2105), and the sixth straight waterway (2106). Six radially arranged cylindrical waterways are connected to the outer side of the circular waterway (2107). The six radially arranged cylindrical waterways connected to the outer side of the circular waterway (2107) are formed by a seventh straight waterway (2108) and an eighth straight waterway (2109). The seventh straight water channel (2109), the eighth straight water channel (2110), the ninth straight water channel (2111), the eleventh straight water channel (2112), and the twelfth straight water channel (2113) are arranged in a circular array. The center of the circular array is located at the center of the rotating shaft. The centrifugal force of the rotating shaft (09) is used to make the coolant flow smoothly.

[0008] In a preferred embodiment: the housing water channel (20) located between the motor housing (16) and the integrated motor inner housing-rear end cover (18) is divided into two parts: the upper part (2001) and the lower part (2002) of the housing water channel. The two parts are independent of each other. The housing water channel disconnection point (2003) is located in the middle of the housing. The first water inlet (2004) of the upper part (2001) and the second water inlet (2005) of the lower part (2002) of the housing water channel are arranged on both sides of the housing water channel disconnection point (2003). A coolant outlet is arranged at the end of the water channel near the end of the housing.

[0009] In a preferred embodiment: the main body of the casing water channel (20) is composed of a spiral structure formed by sweeping with a square cross section, and also includes a compensation part for the empty part at the end of the spiral. A first buffer ramp (2006) and a second buffer ramp (2007) are respectively arranged at the dividing point between the compensation part and the main body to divert the coolant.

[0010] In a preferred embodiment: the housing water channel (20) is formed by the cavity formed by the motor outer shell (16) and the integrated motor inner shell-rear end cover (18); the inner wall of the housing water channel (20) is formed by the integrated motor inner shell-rear end cover (18), and the outer wall is formed by the motor outer shell (16);

[0011] The integrated motor housing-rear end cover assembly (18) is provided with a first coolant baffle (12), the inner side of which is in contact with the motor shaft (09), and the outer side of which is fixedly connected to the integrated motor housing-rear end cover assembly (18); the lower side of the first coolant baffle (12) is in contact with the coolant, the upper side is in contact with the air and is provided with a first safety cavity (1801), and the safety cavity is also provided with a drain hole.

[0012] In a preferred embodiment: a first bearing (10) is arranged in the integrated motor inner housing-rear end cover assembly (18), and the integrated motor inner housing-rear end cover assembly (18) and the motor shaft (09) are connected by an interference fit; the integrated motor inner housing-rear end cover assembly (18) isolates the first safety cavity (1801) and the first bearing (10) through the first protrusion (1802) and indirectly contacts the motor shaft (09) through the first sealing ring (11).

[0013] In a preferred embodiment: a second coolant baffle (06) and a third coolant baffle (07) are arranged in the front cover (08) of the motor. The inner sides of the second coolant baffle (06) and the third coolant baffle (07) are in contact with the motor shaft (09), and the outer sides are fixedly connected to the front cover (08) of the motor. The upper side of the second coolant baffle (06) is in contact with the coolant, the lower side is in contact with the air and a second safety cavity (0803) is provided. The lower side of the third coolant baffle (07) is in contact with the coolant, the upper side is in contact with the air and a third safety cavity (0804) is provided.

[0014] In a preferred embodiment: a second bearing (03) is arranged in the front end cover (08) of the motor, and the front end cover (08) of the motor and the motor shaft (09) are connected by an interference fit; the front end cover (08) of the motor isolates the second safety cavity (0801) and the second bearing (03) through the second protrusion (0803) and indirectly contacts the motor shaft (09) through the second sealing ring (02); the front end cover (08) of the motor isolates the third safety cavity (0802) from the outside through the third protrusion (0804) and indirectly contacts the motor shaft (09) through the third sealing ring (01).

[0015] In a preferred embodiment: an axial fan (05) is arranged on the upper part of the motor shaft (09); the inner side of the axial fan (05) is fixedly connected to the motor shaft (09) and rotates with the shaft; the lower side of the axial fan (05) contacts the protruding part of the motor shaft (09), and the upper side contacts the sleeve (04); the upper side of the sleeve contacts the second bearing (03) to provide support for it;

[0016] The first coolant baffle (12), the second coolant baffle (06), and the third coolant baffle (07) have the same shape, size, working principle, and connection method with the fixing component.

[0017] In a preferred embodiment: a rear end cover hood (19) is arranged on the lower side of the integrated motor inner housing-rear end cover integration (18), and a front end cover hood (15) is arranged on the upper side of the motor front end cover (08), so as to ensure the exchange and heat exchange between the air inside the motor and the outside air while preventing dust from entering the motor.

[0018] The right side of the motor inner housing-rear end cover integration (18) is provided with a first support frame (1803) and a second support frame (1804); the right side of the motor outer housing (16) is provided with a third support frame (1601) and a fourth support frame (1602); the first support frame (1803), the second support frame (1804), the third support frame (1601), and the fourth support frame (1602) share the weight from the entire motor.

[0019] In a preferred embodiment: the water inlet of the motor inner housing-rear end cover integration (18) is provided with a first water guide (13); the motor outer housing (16) is provided with a second water guide (14); the water guide is connected to an external cooling water pipe to ensure smooth flow of cooling water.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. Compared with traditional spiral casing water channels, this invention increases the heat exchange area of ​​the coolant and greatly reduces the coolant pressure by dividing it into upper and lower independent parts, adding a compensation section at the end, and setting a coolant diversion buffer ramp in the compensation section, thereby reducing the requirement for coolant driving force. At the same time, dividing the traditional water-cooled casing into two independent components, inner and outer, reduces the difficulty of manufacturing and maintenance.

[0022] 2. Compared with traditional water-cooled motors, this invention improves the cooling efficiency of permanent magnets by adding cooling water channels in the shaft, thereby improving motor efficiency and reducing the risk of permanent magnet demagnetization.

[0023] 3. Compared with traditional water-cooled motors, this invention reduces motor temperature rise by adding an axial fan mounted on the shaft and ventilation openings at the bottom and top of the motor to create forced convection of air inside and outside the motor.

[0024] 4. Compared with traditional water-cooled motors, this invention solves the problem of coolant sealing and leakage risk in the shaft water channel by setting a coolant baffle and safety cavity in the integrated motor inner housing - the rear end cover is integrated into the motor outer housing. Attached Figure Description

[0025] Figure 1 This is an exploded view of the present invention;

[0026] Figure 2 This is a cross-sectional schematic diagram of the present invention;

[0027] Figure 3 This is a schematic diagram of the overall cooling water channel of the present invention;

[0028] Figure 4 This is a simulation model diagram of the present invention in finite element analysis software;

[0029] Figure 5 The image shows a simulation model of a traditional motor cooling structure in finite element analysis software.

[0030] Figure 6 This is a temperature comparison chart showing the cooling effect of the present invention on permanent magnets compared to that of traditional cooling water channels;

[0031] Figure 7 This is a temperature comparison diagram of the cooling effect of the present invention and traditional cooling water channels on the windings;

[0032] Figure 8 This is a temperature comparison diagram of the cooling effect of the present invention and traditional cooling water channels on the winding insulator;

[0033] Figure 9 This is a comparison diagram of the pressure distribution of the present invention and traditional cooling water channels in the casing water channels.

[0034] Explanation of reference numerals in the attached drawings: 01, Third sealing ring; 02, Second sealing ring; 03, Second bearing; 04, Sleeve; 05, Axial fan; 06, Second coolant baffle ring; 07, Third coolant baffle ring; 08, Motor front end cover; 09, Motor shaft; 10, First bearing; 11, First sealing ring; 12, First coolant baffle ring; 13, First water guide; 14, Second water guide; 15, Front end cover shroud; 16, Motor housing; 17, Motor stator / rotor integration; 18, Integrated motor inner housing - rear end cover integration; 19, Rear end cover shroud; 2 0. Housing water channel; 21. Shaft water channel; 0801. Second safety cavity; 0802. Third safety cavity; 0803. Second protrusion; 0804. Third protrusion; 1601. Third support frame; 1602. Fourth support frame; 1801. First safety cavity; 1802. First protrusion; 1803. First support frame; 1804. Second support frame; 2001. Upper part of housing water channel; 2002. Lower part of housing water channel; 2003. Housing water channel disconnection point; 2004. First water inlet; 2005. Second water inlet; 2006, First Buffer Ramp; 2007, Second Buffer Ramp; 2101, First Straight-Cylinder Waterway; 2102, Second Straight-Cylinder Waterway; 2103, Third Straight-Cylinder Waterway; 2104, Fourth Straight-Cylinder Waterway; 2105, Fifth Straight-Cylinder Waterway; 2106, Sixth Straight-Cylinder Waterway; 2107, Circular Waterway; 2108, Seventh Straight-Cylinder Waterway; 2109, Eighth Straight-Cylinder Waterway; 2110, Ninth Straight-Cylinder Waterway; 2111, Tenth Straight-Cylinder Waterway; 2112, Eleventh Straight-Cylinder Waterway; 2113, Twelfth Straight-Cylinder Waterway. Detailed Implementation

[0035] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0036] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0037] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0038] Reference Figures 1 to 9This application provides a dual cooling system for a permanent magnet synchronous motor, including a third sealing ring 01, a second sealing ring 02, a second bearing 03, a sleeve 04, an axial fan 05, a second coolant baffle ring 06, a third coolant baffle ring 07, a motor front end cover 08, a motor shaft 09, a first bearing 10, a first sealing ring 11, a first coolant baffle ring 12, a first water guide 13, a second water guide 14, a front end cover shroud 15, a motor housing 16, a motor stator / rotor integration 17, an integrated motor inner housing-rear end cover integration 18, a rear end cover shroud 19, a housing water channel 20, and a shaft water channel 21.

[0039] In an embodiment of the present invention, the integrated motor inner housing-rear end cover 18 is provided with a water inlet and a ventilation port, and the motor front end cover 08 is provided with a water outlet and a ventilation port; the motor stator / rotor integrated 17 comprises a stator core, a winding insulator, a winding, a permanent magnet, and a rotor core; the motor stator core is fixedly connected to the integrated motor inner housing-rear end cover 18, and the motor rotor core is fixedly connected to the motor shaft 09; the motor shaft 09 is rotatably connected to the motor front end cover 08 and the integrated motor inner housing-rear end cover 18;

[0040] In an embodiment of the present invention, the dual cooling system further includes a first coolant baffle ring 12, a second coolant baffle ring 06, a third coolant baffle ring 07, a front cover shroud 15, and a rear cover shroud 19; the first coolant baffle ring 12 is fixedly connected to the inner side of the integrated motor inner housing-rear cover assembly 18, the second coolant baffle ring 06 and the third coolant baffle ring 07 are fixedly connected to the inner side of the motor front cover 08; the front cover shroud 15 is fixedly connected to the upper side of the motor front cover 08, and the rear cover shroud 19 is fixedly connected to the lower side of the integrated motor inner housing-rear cover assembly 18.

[0041] In an embodiment of the present invention, the dual cooling system further includes a first water guide 13 and a second water guide 14; the first water guide 13 and the second water guide 14 are respectively fixedly connected to the water inlet on the left side of the integrated motor inner housing-rear end cover 18 and the water outlet on the left side of the motor front end cover 08, which facilitates the connection of water pipes to the water inlet and the water outlet.

[0042] In an embodiment of the present invention, the dual cooling system further includes a third sealing ring 01, a second sealing ring 02, a second bearing 03, a sleeve 04, an axial fan 05, a first bearing 10, and a first sealing ring 11; the first sealing ring 11 is fixedly connected to the integrated motor inner housing-rear end cover 18 and contacts the motor shaft 09; the third sealing ring 01 and the second sealing ring 02 are fixedly connected to the motor front end cover 08 and contact the motor shaft 09; the axial fan 05 is fixedly connected to the motor shaft 09, with its lower side contacting the shoulder of the motor shaft 09 and its upper side contacting the lower side of the axial fan 05; the inner side of the second bearing 03 is interference-fitted with the motor shaft 09, its lower part contacts the sleeve 04, and its upper side contacts the motor front end cover 08; the sleeve 04 is fixedly connected to the motor shaft 09; the upper side of the first bearing 10 contacts the shoulder of the motor shaft 09, its lower side contacts the integrated motor inner housing-rear end cover 18, and its inner side is interference-fitted with the motor shaft 09.

[0043] In an embodiment of the present invention, the dual cooling system further includes a motor housing 16; the motor housing 16 is fixedly connected to the integrated motor inner housing-rear end cover 18 at a specific mating angle, and the cavity formed by the connection forms a complete rotating shaft water channel 20; the interior of the integrated motor inner housing-rear end cover 18 is fixedly connected to the motor front end cover 08; the motor housing 16 and the integrated motor inner housing-rear end cover 18 are connected to the outside through four support frames.

[0044] In an embodiment of the present invention, the upper end of the motor shaft 09 is connected to a mechanical structure that drives the air compressor. The motor converts external electrical energy into mechanical energy and outputs it to the air compressor through the motor shaft 09 to provide driving force for the air compressor.

[0045] This invention provides a dual cooling system for a permanent magnet synchronous motor. The system utilizes the circulation of coolant inside the housing and the shaft to cool the motor. At the same time, the axial fan 05 rotates with the motor shaft 09 to generate forced air convection, which further improves the cooling efficiency of the motor and reduces the temperature rise of the motor.

[0046] The working process of this invention is as follows:

[0047] When the motor is working, cooling water from the outside enters the machine body through the first inlet 2004 of the upper part 2001 of the housing water channel and the second inlet 2005 of the lower part 2002 of the housing water channel. The upper and lower coolant flows through the first water channel buffer ramp 2006 and the second buffer ramp 2007 respectively, forming two water flows, which finally converge at the outlet at the end of the water channel, thereby carrying away heat.

[0048] When the motor is operating, cooling water from the outside enters the motor body through the first water guide 13, flows through the cavity for coolant in the integrated motor inner housing-rear end cover assembly 18, and enters the motor shaft 09. The coolant in the shaft water channel 21 flows out through the cooling water through-hole, passes through the cavity for coolant in the motor front end cover 08, and is finally discharged from the motor body through the second water guide 14, carrying away heat. Simultaneously, leaks caused by fatigue, aging, or other reasons at the connection points between the motor shaft 09 and the motor outer housing 16, and the integrated motor inner housing-rear end cover assembly 18, can be promptly discharged from the motor body through the first safety cavity 1801, the second safety cavity 0801, and the third safety cavity 0802.

[0049] When the motor is working, the axial fan 05 rotates along with the motor shaft 09, causing forced convection between the air inside the motor and the outside, which carries away some of the heat.

[0050] The simulation process and results of the heat dissipation effect and cooling hydraulic pressure in finite element software are analyzed as follows:

[0051] A motor cooling model is built in finite element software for simulation, such as... Figure 4 As shown: The simulation model of this invention includes simplified models of the motor stator / rotor assembly 17, the housing simplified model, the housing water channel 20, and the shaft water channel 21; wherein the motor housing model is simplified by merging the motor outer shell 16 with the integrated motor inner shell - rear end cover 18, ignoring the motor front end cover and rear end cover parts, and adding boundary conditions, thereby reducing unnecessary simulation calculations; the shaft water channel model is simplified by ignoring the water channel near the upper outlet of the shaft water channel 21 and adding boundary conditions, thereby reducing unnecessary simulation calculations. Figure 5 As shown: As a control group for this invention, the traditional water-cooled motor simulation model also includes the motor stator / rotor assembly, housing, and water channels. Simulation results for components of the motor with high temperature rise requirements are as follows: Figure 6-8 As shown, the highest temperature of the permanent magnet under this invention is 53 degrees Celsius, while the highest temperature of the permanent magnet under the traditional cooling structure is 66.7 degrees Celsius, a decrease of approximately 13.7 degrees Celsius. The highest temperature of the winding under this invention is 67 degrees Celsius, while the highest temperature of the winding under the traditional cooling structure is 72.8 degrees Celsius, a decrease of approximately 5.8 degrees Celsius. The highest temperature of the winding insulator under this invention is 67 degrees Celsius, while the highest temperature of the winding insulator under the traditional cooling structure is 72.8 degrees Celsius, a decrease of approximately 5.8 degrees Celsius. The simulation results for the casing water channel pressure are as follows: Figure 9 As shown, the maximum coolant pressure under the present invention is 3.54 Pa, while the maximum coolant pressure under the traditional cooling structure is 21.9 Pa, a decrease of approximately 18.36 Pa.

[0052] Based on the simulation results analysis in the finite element software, it can be seen that the dual cooling structure proposed in this invention, compared with the cooling structure of traditional water-cooled motors, demonstrates a significant improvement in cooling performance and a significant reduction in the required coolant driving force.

[0053] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A dual-cooling structure for a permanent magnet synchronous motor used in an air compressor, characterized in that: Includes motor housing (16), integrated motor inner housing-rear end cover integration (18), housing water channel (20) located between motor housing and integrated motor inner housing-rear end cover integration (18), motor front end cover (08), motor shaft (09), shaft water channel (21) located in motor shaft, axial fan (05) located on motor shaft, and permanent magnet synchronous motor stator / rotor assembly (17); The main body of the shaft water channel (21) located in the motor shaft (09) is composed of six axially arranged cylindrical water channels. The cylindrical water channel is composed of a first straight cylindrical water channel (2101), a second straight cylindrical water channel (2102), a third straight cylindrical water channel (2103), a fourth straight cylindrical water channel (2104), a fifth straight cylindrical water channel (2105), and a sixth straight cylindrical water channel (2106). The first straight cylindrical water channel (2101), the second straight cylindrical water channel (2102), the third straight cylindrical water channel (2103), the fourth straight cylindrical water channel (2104), the fifth straight cylindrical water channel (2105), and the sixth straight cylindrical water channel (2106) are arranged in a circular array. The center of the circular array is located at the center of the shaft. The circular array arrangement reduces the non-uniformity caused by rotational motion during operation. The rotating waterway (21) is connected near the water outlet by a circular waterway (2107) to the first straight waterway (2101), the second straight waterway (2102), the third straight waterway (2103), the fourth straight waterway (2104), the fifth straight waterway (2105), and the sixth straight waterway (2106). Six radially arranged cylindrical waterways are connected to the outer side of the circular waterway (2107). The six radially arranged cylindrical waterways connected to the outer side of the circular waterway (2107) are formed by a seventh straight waterway (2108) and an eighth straight waterway. (2109), Ninth straight water channel (2110), Tenth straight water channel (2111), Eleventh straight water channel (2112), Twelfth straight water channel (2113), and Seventh straight water channel (2108), Eighth straight water channel (2109), Ninth straight water channel (2110), Tenth straight water channel (2111), Eleventh straight water channel (2112) and Twelfth straight water channel (2113) are arranged in a circular array, with the center of the circular array located at the center of the rotating shaft, and the centrifugal force of the rotating shaft (09) of the motor is used to make the coolant flow smoothly.

2. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 1, characterized in that: The housing water channel (20) located between the motor housing (16) and the integrated motor inner housing-rear end cover (18) is divided into two parts: the upper part (2001) and the lower part (2002). The two parts are independent of each other. The housing water channel disconnection point (2003) is located in the middle of the housing. The first water inlet (2004) of the upper part (2001) and the second water inlet (2005) of the lower part (2002) are arranged on both sides of the housing water channel disconnection point (2003). A coolant outlet is arranged at the end of the water channel near the end of the housing.

3. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 1, characterized in that: The main body of the casing water channel (20) is composed of a spiral structure formed by sweeping with a square cross-section. It also includes a compensation part for the empty part at the end of the spiral structure. A first buffer ramp (2006) and a second buffer ramp (2007) are arranged at the dividing point between the compensation part and the main body to divert the coolant.

4. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 1, characterized in that: The housing water channel (20) is formed by the cavity formed by the motor outer shell (16) and the integrated motor inner shell-rear end cover (18); the inner wall of the housing water channel (20) is formed by the integrated motor inner shell-rear end cover (18), and the outer wall is formed by the motor outer shell (16). The integrated motor inner housing-rear end cover assembly (18) is provided with a first coolant baffle ring (12), the inner side of which is in contact with the motor shaft (09), and the outer side of which is fixedly connected to the integrated motor inner housing-rear end cover assembly (18); the lower side of the first coolant baffle ring (12) is in contact with the coolant, the upper side is in contact with the air and is provided with a first safety cavity (1801), and the safety cavity is also provided with a drain hole.

5. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 1, characterized in that: The integrated motor housing-rear end cover assembly (18) is provided with a first bearing (10), which is connected to the motor shaft (09) by an interference fit. The integrated motor housing-rear end cover assembly (18) isolates the first safety cavity (1801) from the first bearing (10) by a first protrusion (1802) and indirectly contacts the motor shaft (09) by a first sealing ring (11).

6. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 4, characterized in that: A second coolant baffle (06) and a third coolant baffle (07) are arranged in the front cover (08) of the motor. The inner side of the second coolant baffle (06) and the third coolant baffle (07) are in contact with the motor shaft (09), and the outer side is fixedly connected to the front cover (08) of the motor. The upper side of the second coolant baffle (06) is in contact with the coolant, the lower side is in contact with the air and a second safety cavity (0801) is provided. The lower side of the third coolant baffle (07) is in contact with the coolant, the upper side is in contact with the air and a third safety cavity (0802) is provided.

7. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 6, characterized in that: The motor front cover (08) is provided with a second bearing (03), which is connected to the motor shaft (09) by an interference fit. The motor front cover (08) isolates the second safety cavity (0801) from the second bearing (03) by a second protrusion (0803) and indirectly contacts the motor shaft (09) by a second sealing ring (02). The motor front cover (08) isolates the third safety cavity (0802) from the outside by a third protrusion (0804) and indirectly contacts the motor shaft (09) by a third sealing ring (01).

8. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 7, characterized in that: An axial fan (05) is arranged on the upper part of the motor shaft (09); the inner side of the axial fan (05) is fixedly connected to the motor shaft (09) and rotates with the shaft; the lower side of the axial fan (05) contacts the protruding part of the motor shaft (09), and the upper side contacts the sleeve (04); the upper side of the sleeve contacts the second bearing (03) to provide support for it; The first coolant baffle (12), the second coolant baffle (06), and the third coolant baffle (07) have the same shape, size, working principle, and connection method with the fixing component.

9. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 1, characterized in that: The lower side of the integrated motor inner housing-rear end cover assembly (18) is provided with a rear end cover hood (19), and the upper side of the motor front end cover (08) is provided with a front end cover hood (15), which ensures the exchange and heat exchange between the internal air and the external air of the motor while preventing dust from entering the motor. The integrated motor inner housing-rear end cover assembly (18) is provided with a first support frame (1803) and a second support frame (1804) on the right side; the motor outer housing (16) is provided with a third support frame (1601) and a fourth support frame (1602) on the right side; the first support frame (1803), the second support frame (1804), the third support frame (1601), and the fourth support frame (1602) share the weight from the entire motor.

10. The dual-cooling structure for a permanent magnet synchronous motor for an air compressor according to claim 1, characterized in that: The water inlet of the integrated motor inner housing-rear end cover (18) is provided with a first water guide (13); the motor outer housing (16) is provided with a second water guide (14); the water guide is connected to the external cooling water pipe to ensure smooth flow of cooling water.

Images