Electric motor

Abstract

Provided in the embodiments of the present application is an electric motor, comprising a rotor assembly, end covers, heat dissipation cavities and bearings, wherein the rotor assembly is provided with air guide channels, which extend in the axial direction of the rotor assembly, the end covers are arranged at end portions of the air guide channels, and have bearing chambers; the heat dissipation cavities are arranged in peripheral sides of the bearing chambers; the air guide channels are in communication with the outside by means of the heat dissipation cavities; the bearings are arranged in the bearing chambers; and heat of the bearings can be transferred into the heat dissipation cavities. In the electric motor provided in the embodiments of the present application, an external airflow can flow through the air guide channels and the heat dissipation cavities, and can simultaneously take away heat in the heat dissipation cavities that is transferred from the bearings; and heat generated by the bearings during operation can be continuously transferred to the heat dissipation cavities and can be taken away from the heat dissipation cavities by the external airflow; therefore, the heat cannot be accumulated in quantity in the bearing chambers, and thus the temperature of the bearings can be effectively controlled, thereby avoiding lubrication failure caused by an extremely high temperature of the bearings, improving the operation reliability of the bearings, and prolonging the service life of the bearings to a certain extent.

Description

A motor

[0001] This application is based on the Chinese patent application with application number 202310789367.5 and application date June 29, 2023, and claims the priority of the Chinese patent application. The entire content of the above patent application is hereby introduced into this application as a reference. Technical Field

[0002] The present application relates to the technical field of motors, and in particular to a motor. Background Art

[0003] In related technologies, the bearings of the motor are used to support the rotating shaft. When the bearings are working at high speed, they will generate heat. As the bearing temperature rises, it will have an adverse effect on its lubrication condition. When working for a long time under poor lubrication conditions, the hidden dangers and risks of bearing failure increase, and the service life of the bearings will also be affected.

[0004] Summary of the Invention

[0005] In view of this, the embodiments of the present application hope to provide a motor that is conducive to heat dissipation of the bearing, thereby improving the reliability of the bearing operation.

[0006] To achieve the above objectives, an embodiment of the present application provides a motor, comprising:

[0007] A rotor assembly, wherein the rotor assembly is provided with an air guide channel, and the air guide channel extends along the axial direction of the rotor assembly;

[0008] An end cover provided at the end of the air guide channel, the end cover having a bearing chamber;

[0009] A heat dissipation cavity is provided on the peripheral side of the bearing chamber, and the air guide channel is connected to the outside through the heat dissipation cavity;

[0010] The heat of the bearing disposed in the bearing chamber can be transferred to the heat dissipation cavity.

[0011] In one embodiment, the outer side wall of the bearing chamber and the rotor assembly together define the heat dissipation cavity; or, the end cover forms the heat dissipation cavity.

[0012] In one embodiment, the rotor assembly includes a rotor pressing ring and a rotor core, wherein the rotor pressing ring is arranged at one axial end of the rotor core;

[0013] The rotor pressure ring is provided with an air passage, the rotor core is provided with the air guide channel, and the air guide channel is connected with the heat dissipation cavity through the air passage;

[0014] The outer side wall of the bearing chamber and the side of the rotor pressure ring facing away from the rotor core jointly define the heat dissipation cavity.

[0015] In one embodiment, the rotor pressure ring includes a body and an air guide tube having an air guide cavity, wherein the body is arranged at one axial end of the rotor core, and the air guide tube is arranged at one end of the body away from the rotor core;

[0016] The air guide tube is arranged around the circumference of the bearing chamber and defines the heat dissipation cavity together with the outer side wall of the bearing chamber.

[0017] In one embodiment, the size of the air guide tube gradually increases from an end close to the body to an end away from the body.

[0018] In one embodiment, the end cover includes a cover body and a cylinder having the bearing chamber, one end of the cylinder is connected to the top wall of the cover body, and the bearing chamber passes through the top wall of the cover body;

[0019] The cover is arranged on one end of the air guide tube away from the rotor core, at least a portion of the column extends into the air guide cavity, and the heat dissipation cavity is defined between the cover, the outer wall of the column and the inner wall of the air guide cavity.

[0020] In one embodiment, the cover body is provided with an air hole penetrating through the top wall of the cover body, and the heat dissipation cavity is connected with the outside through the air hole.

[0021] In one embodiment, the cover is provided with a first air outlet, which passes through the side wall of the cover and communicates with the outside;

[0022] A portion of the top wall of the cover is recessed toward the air guide tube to form a recessed area, the recessed area is arranged around the circumference of the bearing chamber, and the air holes communicate with the recessed area and the heat dissipation cavity;

[0023] The end cover also includes a panel, which is arranged above the recessed area and surrounds the recessed area to form a guide cavity. A second air outlet is also provided on the top wall of the cover body, and the guide cavity is connected to the first air outlet through the second air outlet.

[0024] In one embodiment, an annular boss is formed on a side of the top wall of the cover body facing the air guide tube, and a side wall of the annular boss is gap-fitted with a side wall of the air guide tube.

[0025] In one embodiment, the end of the air guide channel includes an air inlet end and an air outlet end, the number of the end cover and the number of the air guide tube are both two, one of the two end covers is a first end cover, and the other is a second end cover, the first end cover is arranged at the air inlet end, and the second end cover is arranged at the air outlet end; one of the two air guide tubes is a first air guide tube, and the other is a second air guide tube, the first air guide tube is arranged at the air inlet end, and the second air guide tube is arranged at the air outlet end;

[0026] The annular boss of the first end cover is a first annular boss, and the outer side wall of the first annular boss is gap-fitted with the inner side wall of the first air guide tube.

[0027] In one embodiment, the annular boss of the second end cover is a second annular boss, and an inner side wall of the second annular boss is gap-fitted with an outer side wall of the second air guide tube.

[0028] In one embodiment, an air guide blade is formed on the inner side wall of at least one of the first air guide tube and the second air guide tube, and the air guide blade extends along the axial direction of the second air guide tube.

[0029] The motor of the embodiment of the present application has an end cover with a bearing chamber, and the bearing is arranged in the bearing chamber. The end cover provides an installation position for the bearing, which is convenient for bearing installation; a heat dissipation cavity is provided on the peripheral side of the bearing chamber, and the heat of the bearing can be transferred to the heat dissipation cavity; the rotor assembly is provided with an air guide channel, and the air guide channel extends along the axial direction of the rotor assembly; the end cover is provided at the end of the air guide channel, and the air guide channel is connected to the outside through the heat dissipation cavity. The external air flow can flow through the air guide channel and the heat dissipation cavity, and at the same time can take away the heat transferred from the bearing in the heat dissipation cavity. The heat generated by the bearing during operation can be continuously transferred to the heat dissipation cavity and carried away from the heat dissipation cavity by the external air flow. In this way, a large amount of heat will not be accumulated in the bearing chamber, and the temperature of the bearing can be effectively controlled, thereby avoiding lubrication failure caused by excessive bearing temperature, improving the reliability of the bearing operation, and delaying the service life of the bearing to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG1 is an axial cross-sectional view of a motor according to an embodiment of the present application;

[0031] Figure 2 is an enlarged schematic diagram of point A in Figure 1;

[0032] Figure 3 is an enlarged schematic diagram of point B in Figure 1;

[0033] FIG4 is an axial cross-sectional view of a motor according to another embodiment of the present application;

[0034] FIG5 is a schematic structural diagram of an air guide tube according to an embodiment of the present application. DETAILED DESCRIPTION

[0035] It should be noted that, unless there is a conflict, the embodiments and technical features in the embodiments of this application can be combined with each other, and the detailed description in the specific implementation method should be understood as an explanation of the purpose of this application and should not be regarded as an improper restriction on this application.

[0036] In the description of the embodiments of the present application, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] An embodiment of the present application provides a motor. Referring to FIG. 1 , the motor 100 includes a rotor assembly 10 , an end cover 20 , a heat dissipation cavity 100 a , and a bearing 30 .

[0038] The type of the motor 100 is not limited. For example, it can be an asynchronous motor, a DC motor, a permanent magnet motor, a brushless DC motor, etc. For example, the embodiment of the present application uses a permanent magnet motor as an example.

[0039] 1 , the motor 100 generally includes a rotating shaft 60, and the rotor assembly 10 is sleeved on the rotating shaft 60 and can rotate synchronously with the rotating shaft 60. In other words, the rotation of the rotor assembly 10 can drive the rotating shaft 60 to rotate, thereby achieving power output.

[0040] 1 to 3 , the end cover 20 has a bearing chamber 22 a , and the bearing 30 is disposed in the bearing chamber 22 a . The end cover 20 provides an installation position for the bearing 30 , facilitating installation of the bearing 30 .

[0041] A heat dissipation cavity 100a is provided around the bearing chamber 22a, into which heat from the bearing 30 can be transferred. The rotor assembly 10 is provided with an air guide channel 12a, which extends axially along the rotor assembly 10. The end cap 20 is provided at the end of the air guide channel 12a. The air guide channel 12a communicates with the outside world through the heat dissipation cavity 100a. In other words, external airflow can flow through the air guide channel 12a and the heat dissipation cavity 100a, and at the same time remove heat from the heat dissipation cavity 100a transferred from the bearing 30. Heat generated by the bearing 30 during operation can be continuously transferred to the heat dissipation cavity 100a and removed by the external airflow. In this way, a large amount of heat is not accumulated in the bearing chamber 22a, and the temperature of the bearing 30 can be effectively controlled, thereby avoiding lubrication failure caused by excessive temperature of the bearing 30, improving the reliability of the bearing 30, and to a certain extent extending the service life of the bearing 30.

[0042] The air guide channel 12 a passes through the interior of the rotor assembly 10 . When the external airflow passes through the air guide channel 12 a , it can also exchange heat with the rotor assembly 10 , thereby taking away part of the heat generated by the rotor assembly 10 .

[0043] It should be noted that the rotor assembly 10 of the permanent magnet motor generates almost no heat. Therefore, in some embodiments, when the motor 100 is a permanent magnet motor, the external airflow can be used more for cooling the bearing 30, and the cooling effect of the bearing 30 is better.

[0044] It is understood that the end of the air guide channel 12a can be either end or both ends of the axial direction. For example, referring to Figure 1, both ends of the air guide channel 12a are provided with end caps 20. The two axial ends of the air guide channel 12a are connected to the outside world through a heat dissipation cavity 100a. The external air enters through one end of the motor 100 and is discharged at the other end. In this way, the bearings 30 at both ends of the motor 100 can be cooled by the same heat dissipation system, forming a through-type heat dissipation system at both ends of the axial direction of the motor 100, and the temperature of the bearings 30 at both ends of the axial direction of the motor 100 is more balanced.

[0045] In addition, the bearings 30 at both axial ends of the motor 100 are cooled by the same heat dissipation system, which occupies less axial space of the motor 100 and allows the motor 100 to be designed to be more compact.

[0046] The number of the air guiding channels 12a is not limited, for example, there can be multiple air guiding channels 12a. Multiple air guiding channels 12a can increase the flow rate of external airflow and improve the heat dissipation effect.

[0047] It should be noted that, in the embodiments of the present application, "a plurality" refers to two or more.

[0048] Specifically, the number of air guide channels 12a can be 6, and the 6 air guide channels 12a are evenly distributed in the circumferential direction of the rotor assembly 10. In this way, the external airflow flowing through the heat dissipation cavity 100a in the circumferential direction is more evenly distributed, and the cooling effect on the circumferential side of the bearing 30 is more uniform, which to a certain extent avoids the occurrence of local high temperature in the bearing 30.

[0049] The shape of the air guide channel 12a is not limited, and can be, for example, cylindrical, prismatic, etc.

[0050] In a specific embodiment, the orthographic projection of the side wall forming the air guiding channel 12 a along the axial direction of the air guiding channel 12 a is a fan ring, and the center of the fan ring is on the rotation center line of the rotating shaft 60 .

[0051] The position of the air guide channel 12a on the rotor assembly 10 is not limited. For example, please refer to Figure 1. The air guide channel 12a can be set at a position on the rotor assembly 10 that is close to the rotation center line of the rotating shaft 60. In this way, the air guide channel 12a can be away from the magnetic circuit of the rotor assembly 10, and the heat and temperature are low, which can prevent the heat generated by the rotor assembly 10 from being transferred to the bearing 30 through the air guide channel 12a.

[0052] It should be noted that the formation method of the heat dissipation cavity 100a is not limited. In some embodiments, referring to Figures 1 and 2, the outer wall of the bearing chamber 22a and the rotor assembly 10 jointly define the heat dissipation cavity 100a. In other words, after the end cover 20 is positioned at the end of the air guide channel 12a, a gap exists between the side of the end cover 20 facing the air guide channel 12a and the rotor assembly 10. This gap can form the heat dissipation cavity 100a. The heat dissipation cavity 100a is formed by the rotor assembly 10 and the end cover 20, which is simple to form and easy to implement.

[0053] In other embodiments, the end cap 20 forms a heat dissipation cavity 100a. That is, the heat dissipation cavity 100a is a cavity formed integrally with the end cap 20. After the end cap 20 is disposed at the end of the air guide channel 12a, the heat dissipation cavity 100a is connected to the air guide channel 12a.

[0054] It should be noted that the structure of the rotor assembly 10 is not limited. For example, please continue to refer to Figures 1 and 2. In one embodiment, the rotor assembly 10 includes a rotor pressure ring 11 and a rotor core 12. The rotor pressure ring 11 is arranged at one axial end of the rotor core 12. The rotor pressure ring 11 and the rotor core 12 are both sleeved on the rotating shaft 60. The outer wall of the bearing chamber 22a and the side of the rotor pressure ring 11 facing away from the rotor core 12 jointly define a heat dissipation cavity 100a.

[0055] It can be understood that the rotor core 12 is generally obtained by stacking multiple rotor punchings along the axial direction of the rotor punchings. Rotor pressure rings 11 can be set at both ends of the rotor core 12 in the axial direction. The position of the rotor pressure ring 11 on the rotating shaft 60 is relatively fixed. On the one hand, the rotor core 12 can be positioned at one end of the axial direction of the rotating shaft 60 through the rotor pressure ring 11; on the other hand, the area of ​​the rotor pressure ring 11 close to the rotor punching side can also be designed to be as close to the area of ​​the rotor punching as possible. In this way, the rotor pressure ring 11 can also realize the function of pressing multiple rotor punchings.

[0056] The rotor pressing ring 11 is provided with an air passage 11 a , and the rotor core 12 is provided with an air guide channel 12 a . The air guide channel 12 a is communicated with the heat dissipation cavity 100 a through the air passage 11 a .

[0057] The shape of the air passage 11a is not limited. In some embodiments, referring to Figures 1 and 2 , the air guide channel 12a and the air passage 11a are connected and together form a heat dissipation channel. The shape of the air passage 11a matches the shape of the air guide channel 12a. At the connection point between the air passage 11a and the air guide channel 12a, the diameter of the heat dissipation channel remains substantially unchanged. When the external air flows through this connection point, no local vortex is generated, thereby allowing the external airflow to flow more smoothly.

[0058] It should be noted that the structure of the rotor pressure ring 11 is not limited. For example, please refer to Figures 1 to 3. In one embodiment, the rotor pressure ring 11 includes a main body 111 and an air guide tube 112 having an air guide cavity 112a. The main body 111 is arranged at one axial end of the rotor core 12, and the air guide tube 112 is arranged at the end of the main body 111 away from the rotor core 12. The air guide tube 112 is arranged around the circumference of the bearing chamber 22a and defines a heat dissipation cavity 100a with the outer wall of the bearing chamber 22a.

[0059] It can be understood that, in this embodiment, part of the air guiding cavity 112a forms the heat dissipation cavity 100a.

[0060] The main body 111 can be used for positioning one axial end of the rotor core 12 and for pressing a plurality of rotor punchings. The air guide tube 112 is used to define a heat dissipation cavity 100a with the outer wall of the bearing chamber 22a. That is to say, by utilizing the functional differences achieved by various parts of the rotor pressure ring 11, the rotor pressure ring 11 is divided into at least two parts, the main body 111 and the air guide tube 112. On the one hand, the main body 111 and the air guide tube 112 obtained after the splitting have a simpler structure and are easier to process than the integrated rotor pressure ring 11; on the other hand, the main body 111 and the air guide tube 112 achieve different functions and can be processed with different materials respectively. The materials of the main body 111 and the air guide tube 112 can be selected according to actual needs, thereby reducing the overall weight of the rotor pressure ring 11 and reducing costs at the same time.

[0061] The material of the main body 111 is not limited. The main body 111 needs to bear a certain axial force, so it can be made of a material with a relatively high density.

[0062] The material of the air duct 112 is not limited. In some embodiments, the air duct 112 is made of one of aluminum alloy, magnesium alloy, titanium alloy, stainless steel, or nickel alloy. In actual use, the air duct 112 can be selected based on its corrosion resistance, high temperature resistance, and other properties.

[0063] In other embodiments, the air guide tube 112 can be made of insulating materials, such as aerogel fibers, etc., so as to limit the heat generated by other components of the motor 100 from entering the heat dissipation cavity 100a, thereby avoiding the heat generated by other components from affecting the bearing 30, and allowing the external airflow to be used as much as possible to cool the bearing 30, thereby achieving a better cooling effect for the bearing 30.

[0064] The shape of the air duct 112 is not limited. In some embodiments, as shown in Figures 1, 2, and 5, the circumferential outer and inner sidewalls of the air duct 112 are arranged to form a circular ring. In other words, both the inner and outer circumferential walls of the air duct 112 are circular. It will be understood that the rotor assembly 10 rotates synchronously with the rotating shaft 60, and thus the air duct 112 also rotates synchronously with the rotating shaft 60. When the air duct 112 rotates about the rotational centerline of the rotating shaft 60, the air duct 112 with a circular outer wall is more convenient to cooperate with other components.

[0065] In one embodiment, referring to FIG. 1 and FIG. 2 , the size of the air guide tube 112 gradually increases from an end close to the body 111 to an end away from the body 111 .

[0066] The size of the air guide tube 112 refers to the diameter of the shape formed by the inner wall of the air guide tube 112 in a circumferential direction. For example, when the shape formed by the inner wall of the air guide tube 112 in a circumferential direction is circular, the size refers to the diameter. The diameter of the air guide tube 112 gradually increases. In this way, it is convenient for the air guide tube 112 to be arranged around the bearing chamber 22a. At the same time, when the external air flow flows from the heat dissipation cavity 100a to the air passage 11a, the inner wall of the air guide tube 112 can also guide the external air flow into the air passage 11a.

[0067] It should be noted that the bearing chamber 22a is not limited to a specific method of forming the bearing chamber 22a. In some embodiments, the bearing chamber 22a is integrally formed on the end cover 20. In other words, the bearing chamber 22a is a functional area integrated on the end cover 20.

[0068] In other embodiments, referring to Figures 1 to 3, the end cover 20 includes a cover body 21 and a column 22 having a bearing chamber 22a. One end of the column 22 is connected to the top wall of the cover body 21, and the bearing chamber 22a passes through the top wall of the cover body 21. The cover body 21 is covered at one end of the air guide tube 112 away from the rotor core 12, and at least a portion of the column 22 extends into the air guide cavity 112a. The outer wall of the cover body 21, the column 22, and the inner wall of the air guide cavity 112a define a heat dissipation cavity 100a.

[0069] It should be noted that the top wall of the cover 21 refers to the wall of the cover 21 facing the air duct 112 after the cover 21 is covered on the air duct 112. In other words, it is the wall of the cover 21 in the axial direction.

[0070] The bearing chamber 22a passes through the top wall of the cover body 21 , that is, the side of the bearing chamber 22a facing away from the air guide channel 12a is open, thereby facilitating the installation of the bearing 30 into the bearing chamber 22a.

[0071] In this embodiment, the heat of the bearing 30 is transferred to the heat dissipation cavity 100a through the side wall of the column 22. The end cover 20 is divided into at least two parts, the cover body 21 and the column 22, so that they can be processed separately, thereby improving the production efficiency of the end cover 20. At the same time, compared with the end cover 20, the structure of the column 22 and the cover body 21 is simpler and more convenient to process.

[0072] It should be noted that the way the heat dissipation cavity 100a is connected to the outside is not limited. For example, an air hole 21c is provided on the end cover 20, and the external air flow can enter or leave the heat dissipation cavity 100a through the air hole 21c.

[0073] The position of the air hole 21c on the end cover 20 is not limited. For example, please refer to Figures 1 to 3. In one embodiment, the cover body 21 is provided with an air hole 21c that passes through the top wall of the cover body 21, and the heat dissipation cavity 100a is connected to the outside through the air hole 21c.

[0074] It can be understood that the cover 21 is arranged on the end of the air guide tube 112 away from the rotor core 12, and the air hole 21c passes through the top wall of the cover 21. The external air flow can enter or leave the heat dissipation cavity 100a through the end of the motor 100, and the external air flow flows more smoothly and encounters less resistance.

[0075] In a specific embodiment, please continue to refer to Figures 1 to 3. The air hole 21c can be a top wall of the cover body 21 that passes through the cover body 21 along the axial direction. In this way, the air hole 21c is consistent with the opening direction of the air guide channel 12a, further reducing the flow resistance of the external airflow and improving the heat dissipation effect. At the same time, the air hole 21c is opened along the axial direction of the cover body 21. When the thickness of the cover body 21 in the axial direction remains unchanged, the air hole 21c is opened along the axial direction to make the hole length of the air hole 21c smaller, thereby reducing the processing difficulty.

[0076] It should be noted that the number of the air holes 21c is not limited. For example, there are multiple air holes 21c, which increase the flow rate of external airflow and improve heat dissipation efficiency.

[0077] The plurality of air holes 21 c may be evenly distributed around the circumference of the bearing chamber 22 a , thereby making the heat dissipation of the bearing chamber 22 a more uniform.

[0078] It should be noted that the end cover 20 of this embodiment can be provided at any one of the two axial ends of the air guide channel 12a.

[0079] Of course, when end covers 20 are provided at both axial ends of the air guide channel 12a, the end covers 20 of this embodiment can also be used, please refer to Figure 1. The structures of the two end covers 20 are the same, which reduces the design cost. At the same time, the external airflow can enter from the end of one end of the motor 100 and leave from the end of the other end of the motor 100. In this way, the overall resistance encountered by the external airflow flowing inside the motor 100 is smaller, and it can be used for natural ventilation.

[0080] It should be noted that the form of natural ventilation is not limited. For example, the difference in temperature between the inside and outside of the motor 100 may be used to form convection to introduce external airflow.

[0081] Of course, an airflow disturbance component may be provided inside the motor 100 to drive the external airflow to flow through the motor 100 when the motor 100 is running.

[0082] In one embodiment, referring to FIG. 4 , a first air port 21 d is provided on the cover 21 . The first air port 21 d passes through the side wall of the cover 21 and communicates with the outside. The side wall of the cover 21 refers to the wall in the radial direction of the cover 21 .

[0083] Part of the top wall of the cover body 21 is recessed toward the air guide tube 112 to form a recessed area 21e, and an opening is formed on the side of the recessed area 21e facing away from the air guide tube 112. The recessed area 21e is arranged around the circumference of the bearing chamber 22a, and the air hole 21c connects the recessed area 21e and the heat dissipation cavity 100a; the end cover 20 also includes a surrounding plate 23, which is covered above the recessed area 21e and surrounds the recessed area 21e to form a guide cavity 20a, and a second air outlet 21a is also provided on the top wall of the cover body 21, and the guide cavity 20a is connected to the first air outlet 21d through the second air outlet 21a.

[0084] It can be understood that the upper side of the recessed area 21e is the side where the opening is located, and the enclosure 23 is provided on the upper side of the recessed area 21e to close the opening.

[0085] In this embodiment, the first air outlet 21d can be used to connect with an external cooling system, which provides external airflow. A part of the external airflow is used to dissipate heat to the stator assembly 70 and other components of the motor 100 through the first air outlet 21d. In addition, a part of the external airflow can be introduced into the guide cavity 20a through the second air outlet 21a. The guide cavity 20a can also be arranged on the circumference of the bearing chamber 22a. The airflow on the circumference of the bearing 30 can exchange heat with the external airflow in the guide cavity 20a. That is to say, the end cover 20 of this embodiment can divide the external airflow into multiple parts, thereby realizing heat dissipation of multiple components of the motor 100, and has good versatility.

[0086] As mentioned above, when end covers 20 are provided at both axial ends of the air guide channel 12a, the end covers 20 in this embodiment can be used for external airflow to enter the motor 100, and the first air outlet 21d can facilitate the connection of the cooling system to supply external airflow to the motor 100. After the external airflow enters the interior of the motor 100 through the first opening, a part of it can enter the guide cavity 20a through the second opening. The external airflow flows around the circumference of the bearing chamber 22a through the guide cavity 20a, taking away the heat transferred from the bearing 30 to the guide cavity 20a, and further enters the heat dissipation cavity 100a through the air hole 21c, taking away the heat transferred from the bearing 30 to the heat dissipation cavity 100a.

[0087] Of course, the end cover 20 of this embodiment can also be used for the air outlet end of the air guide channel 12a, and the heat dissipation cavity 100a is also connected to the outside through the air hole 21c, the guide cavity 20a, the second air outlet 21a and the first air outlet 21d.

[0088] In one embodiment, referring to FIG. 1 to FIG. 3 , an annular boss 21 b is formed on the top wall of the cover 21 facing the air guide 112 , and the side wall of the annular boss 21 b is gap-fitted with the side wall of the air guide 112 .

[0089] In this embodiment, along the radial direction of the heat dissipation cavity 100a, there is an overlapping area between the annular boss 21b and the air guide tube 112, and the overlapping area has a certain extension length along the axial direction of the air guide tube 112, so that dust can be prevented from entering the interior of the heat dissipation cavity 100a along the radial direction.

[0090] It should be noted that the gap after clearance fit is not limited. For example, after the annular boss 21b and the air guide tube 112 are clearance fit, the gap between the air guide tube 112 and the annular boss 21b in the overlapping area is 0.5 mm to 2 mm.

[0091] It can be understood that the air guide tube 112 rotates synchronously with the rotor core 12, and the annular boss 21b is relatively fixed. That is to say, relative rotation will occur between the air guide tube 112 and the annular boss 21b. The use of clearance fit can enable relative rotation between the two, and at the same time, the gap after clearance fit is limited to a certain range, further preventing dust from entering the heat dissipation cavity 100a.

[0092] It should be noted that the extension length of the overlapping region in the axial direction of the air guide tube 112 is not limited. For example, the extension length is generally 2 mm to 20 mm. This ensures a certain dustproof effect while reducing space occupation. At the same time, the extension length of the annular boss 21b and the air guide tube 112 in the overlapping region is controlled within a certain range, which can save materials and reduce costs to a certain extent.

[0093] In one embodiment, please refer to Figure 1, the end of the air guide channel 12a includes an air inlet end and an air outlet end, and the number of end covers 20 and air guide tubes 112 are both two, one of the two end covers 20 is the first end cover 40, and the other is the second end cover 50, the first end cover 40 is arranged at the air inlet end, and the second end cover 50 is arranged at the air outlet end; one of the two air guide tubes 112 is the first air guide tube, and the other is the second air guide tube, the first air guide tube is arranged at the air inlet end, and the second air guide tube is arranged at the air outlet end.

[0094] It can be understood that, in this embodiment, the external air flow can enter the motor 100 from the air inlet end and leave the motor 100 from the air outlet end.

[0095] The annular boss 21b of the first end cover 40 is a first annular boss. The manner in which the first annular boss is gap-fitted with the first air duct is not limited. For example, please refer to Figures 1 and 3. In one embodiment, the outer wall of the first annular boss is gap-fitted with the inner wall of the first air duct.

[0096] In this embodiment, the column 22 of the first end cover 40 is the first column. When the external airflow flows at the air inlet end, the external airflow enters from the air hole 21c of the first end cover 40. The air hole 21c is located between the first annular boss and the first column. The outer wall of the first annular boss is gap-fitted with the inner wall of the first air guide tube. The first air guide tube in the overlapping area is located on the outer peripheral side of the first annular boss. In this way, when the external airflow enters this overlapping area, the end face of the first air guide tube facing one end of the first end cover 40 will not form a barrier to the external airflow, and the flow resistance of the external airflow is smaller and the flow volume is larger.

[0097] The annular boss 21b of the second end cover 50 is a second annular boss. The manner in which the second annular boss is gap-fitted with the second air duct is not limited. For example, please refer to Figures 1 and 2. In one embodiment, the inner wall of the second annular boss is gap-fitted with the outer wall of the second air duct.

[0098] The column 22 of the second end cover 50 is the second column. When the external airflow flows at the air outlet end, the external airflow flows from the heat dissipation cavity 100a to the air hole 21c. The air hole 21c is located between the second annular boss and the second column. The inner wall of the second annular boss and the outer wall of the second air guide tube are gap-matched. The second annular boss at the overlapping area is located on the outer peripheral side of the second air guide tube. In this way, when the external airflow leaves this overlapping area, the end face of the second annular boss facing one end of the air guide channel 12a will not form a barrier to the external airflow, and the flow resistance of the external airflow is smaller and the flow volume is larger.

[0099] It will be appreciated that, in this embodiment, the air hole 21c of the second end cap 50 serves as the second air hole. Along the axial direction of the rotating shaft 60, the orthographic projection of the wall of the second air hole partially overlaps with the orthographic projection of the second air duct located in the overlapping region. In other words, along the axial direction of the rotating shaft 60, a portion of the inner wall of the second air duct located in the overlapping region is not obstructed by the wall of the second air hole. When external air flows through the heat dissipation cavity 100a toward the second air hole, it passes through the inner wall of the second air duct and then directly enters the second air hole along the axial direction and is discharged to the outside world, thereby further reducing flow resistance.

[0100] In one embodiment, an air guide blade 112b is formed on the inner side wall of at least one of the first air guide tube and the second air guide tube 1, and the air guide blade 112b extends along the axial direction of the second air guide tube.

[0101] It can be understood that the first air guide tube 112 and the second air guide tube 112 both rotate with the rotor core 12, and the air guide blades 112b can also rotate accordingly. In this way, the external air flow can enter the motor 100 through the air inlet section and be discharged from the motor 100 through the air outlet. In this way, the air guide blades 112b can be used to enable the external air flow to circulate inside the motor 100, thereby cooling the bearing 30.

[0102] It can be understood that the air guide blades 112a of this embodiment can be used in the aforementioned solution of utilizing natural ventilation to dissipate heat from the bearing 30.

[0103] It should be noted that the air guide blade 112b can be set on either the first air guide tube 112 or the second air guide tube 112, or both the first air guide tube 112 and the second air guide tube 112 can be provided with the air guide blade 112b. It is only necessary to enable the external air flow to enter the motor 100 from the air inlet section and leave the motor 100 from the air outlet end.

[0104] Specifically, referring to FIG. 1 and FIG. 2 , the following is an example of providing the air guide blades 112 b on the second air guide tube 112 .

[0105] The number of air guide blades 112b is not limited and can be designed according to heat dissipation requirements. For example, the number of air guide blades 112b is six, and the six air guide blades 112b are evenly distributed around the circumference of the second air guide tube 112. This makes the air guiding effect of the second air guide tube 112 more uniform, and the weight distribution around the circumference of the second air guide tube 112 is also more uniform, thereby improving reliability.

[0106] The second air guide tube 112 and the air guide blades 112 b may be formed in any manner, for example, they may be integrally formed. The integrally formed second air guide tube 112 and the air guide blades 112 b have good integrity and high reliability.

[0107] The shape of the air guide blade 112b is not limited. For example, the air guide blade 112b can be designed as a straight plate, so that the external airflow can be discharged from the motor 100 when the motor 100 is running in the forward or reverse direction.

[0108] In some embodiments, when the motor 100 can only rotate in one direction, the air guide blades 112b may be designed with a curved surface according to the flow path of the external airflow to enhance the air guiding effect of the air guide blades 112b.

[0109] In the description of this application, the descriptions with reference to the terms "in one embodiment", "in some embodiments", "in other embodiments", "in yet other embodiments", or "exemplary" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this application, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine different embodiments or examples described in this application and features of different embodiments or examples, unless they are mutually inconsistent.

[0110] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Persons skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application are intended to be within the scope of protection of the present application.

Claims

1. A motor, comprising: A rotor assembly, wherein the rotor assembly is provided with an air guide channel, and the air guide channel extends along the axial direction of the rotor assembly; An end cover disposed at the end of the air guide channel, the end cover having a bearing chamber; A heat dissipation cavity is arranged on the peripheral side of the bearing chamber, and the air guide channel is connected with the outside through the heat dissipation cavity; The heat of the bearing disposed in the bearing chamber can be transferred to the heat dissipation cavity.

2. According to the motor of claim 1, the outer wall of the bearing chamber and the rotor assembly together define the heat dissipation cavity; or, the end cover forms the heat dissipation cavity.

3. The motor according to claim 1, wherein the rotor assembly comprises a rotor pressing ring and a rotor core, and the rotor pressing ring is arranged at one axial end of the rotor core; The rotor pressing ring is provided with an air passage, the rotor core is provided with the air guiding passage, and the air guiding passage is connected with the heat dissipation cavity through the air passage; The outer side wall of the bearing chamber and the side of the rotor pressing ring facing away from the rotor core jointly define the heat dissipation cavity.

4. The motor according to claim 3, wherein the rotor pressing ring comprises a body and an air guide cylinder having an air guide cavity, wherein the body is arranged at one axial end of the rotor core, and the air guide cylinder is arranged at one end of the body away from the rotor core; The air guide tube is arranged around the circumference of the bearing chamber, and defines the heat dissipation cavity together with the outer side wall of the bearing chamber. 5 . The motor according to claim 4 , wherein the size of the air guide tube gradually increases from the direction close to one end of the body to the direction away from one end of the body.

6. The motor according to claim 4, wherein the end cover comprises a cover body and a cylinder having the bearing chamber, one end of the cylinder is connected to the top wall of the cover body, and the bearing chamber passes through the top wall of the cover body; The cover body is arranged on one end of the air guide tube away from the rotor core, at least a part of the column tube extends into the air guide cavity, and the heat dissipation cavity is defined between the cover body, the outer wall of the column tube and the inner wall of the air guide cavity. 7 . The motor according to claim 6 , wherein the cover body is provided with an air hole penetrating through the top wall of the cover body, and the heat dissipation cavity is connected with the outside through the air hole.

8. The motor according to claim 7, wherein the cover is provided with a first air outlet, the first air outlet penetrates the side wall of the cover and communicates with the outside; A portion of the top wall of the cover body is recessed toward the air guide tube to form a recessed area, the recessed area is arranged around the circumference of the bearing chamber, and the air hole communicates with the recessed area and the heat dissipation cavity; The end cover also includes a surrounding plate, which is arranged above the recessed area and surrounds the recessed area to form a guide cavity. A second air outlet is also arranged on the top wall of the cover body, and the guide cavity is connected to the first air outlet through the second air outlet.

9. The motor according to claim 7, wherein an annular boss is formed on a side of the top wall of the cover body facing the air guide tube, and a side wall of the annular boss is gap-matched with a side wall of the air guide tube.

10. The motor according to claim 9, wherein the end of the air guide channel comprises an air inlet end and an air outlet end, the number of the end cover and the number of the air guide cylinder are both two, one of the two end covers is a first end cover, and the other is a second end cover, the first end cover is arranged at the air inlet end, and the second end cover is arranged at the air outlet end; one of the two air guide cylinders is a first air guide cylinder, and the other is a second air guide cylinder, the first air guide cylinder is arranged at the air inlet end, and the second air guide cylinder is arranged at the air outlet end; The annular boss of the first end cover is a first annular boss, and the outer wall of the first annular boss is gap-matched with the inner wall of the first air guide tube; and / or, The annular boss of the second end cover is a second annular boss, and the inner side wall of the second annular boss is gap-matched with the outer side wall of the second air guide cylinder. 11 . The motor according to claim 10 , wherein an air guide blade is formed on an inner side wall of at least one of the first air guide tube and the second air guide tube, and the air guide blade extends along the axial direction of the second air guide tube.

Images