Motor rotor and motor

Abstract

The present application provides a motor rotor and a motor. The motor rotor comprises a front short shaft (4), a rear short shaft (6), a magnetic steel (5) and a sheath (7), wherein the front short shaft (4), the magnetic steel (5) and the rear short shaft (6) are all sleeved in the sheath (7), the magnetic steel (5) is located between the front short shaft (4) and the rear short shaft (6), an internal air path (51) penetrating along the axial direction is provided on the magnetic steel (5), a first axial air path (41) is provided on the front short shaft (4), and a second axial air path (61) is provided on the rear short shaft (6), and the first axial air path (41), the internal air path (51) and the second axial air path (61) are connected in sequence to form a through air path penetrating the motor rotor along the axial direction. According to the motor rotor of the present application, the surface and the interior of the rotor heating part can be effectively cooled, so that the cooling of the rotor is more sufficient.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular to a motor rotor and a motor. Background Art

[0002] High-speed motor rotors generally use metal sheaths to protect permanent magnets. When running at high speeds, high-frequency eddy current losses will be generated inside the rotor sheath and magnetic steel, causing the entire rotor to heat up. Therefore, the heating parts of the rotor must be effectively cooled.

[0003] A rotor axial cooling structure for an air compressor is disclosed in the related art. The rotor of the rotor axial cooling structure includes at least one magnet, and the outside of the magnet has a cooling channel through which a cooling medium flows. The cooling channel includes at least one axial cooling channel and is used to guide the cooling medium along the flow of the magnet. The cooling channel is limited by a recess, and the recess is arranged outside the magnet. The rotor shaft is connected by a bandage. The rotor shaft includes at least one cooling medium channel, which is fluidly connected to the cooling channel. The rotor shaft sections include at least one through hole for the cooling medium at their ends facing away from each other. The magnet is arranged between two disks in the axial direction, and the disks include at least one through hole, which is fluidly connected to the cooling channel geometry. The fluid connection portion includes at least one shoulder on the surface of one of the disks facing the magnet.

[0004] The rotor axial cooling structure realizes the axial circulation of the cooling fluid from the front end to the rear end of the shaft through the above design, so as to cool the permanent magnets and the heating parts of the sheath. Since the cooling channel is designed between the contact surface of the magnet and the sheath, although the outer surface of the sheath and the permanent magnet can be cooled, the cooling effect on the core of the magnet is poor, which is prone to high-temperature demagnetization. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present application is to provide a motor rotor and a motor, which can effectively cool the surface and interior of the heating part of the rotor, so that the cooling of the rotor is more sufficient.

[0006] In order to solve the above problems, the present application provides a motor rotor, including a front short shaft, a rear short shaft, a magnetic steel and a sleeve, the front short shaft, the magnetic steel and the rear short shaft are all sleeved in the sleeve, the magnetic steel is located between the front short shaft and the rear short shaft, and an internal air path running through the axial direction is provided on the magnetic steel, a first axial air path is provided on the front short shaft, and a second axial air path is provided on the rear short shaft. The first axial air path, the internal air path and the second axial air path are connected in sequence to form a through air path running through the motor rotor axially.

[0007] Preferably, the internal air path is located at the center of the magnetic steel.

[0008] Preferably, the internal air path is a circular hole, and the central axis of the internal air path coincides with the central axis of the magnetic steel.

[0009] Preferably, the first axial air path is located on the outer circumferential wall of the front short shaft and / or the inner circumferential wall of the sleeve, and a first end air path is provided on the end surface of the front short shaft facing the magnetic steel, and the internal air path is connected to the first axial air path through the first end air path.

[0010] Preferably, there are at least two first axial air passages, and the at least two first axial air passages are evenly distributed along the circumference of the front short axis.

[0011] Preferably, a first stop flange is provided at one end of the front short shaft away from the magnetic steel, and the first stop flange stops at the axial outer side of the sleeve.

[0012] Preferably, an annular first guide groove is provided on the end surface of the front short shaft away from the magnetic steel, and the first guide groove is connected to each first axial air path.

[0013] Preferably, the second axial air path is located on the outer circumferential wall of the rear short shaft and / or the inner circumferential wall of the sleeve, and a second end air path is provided on the end surface of the rear short shaft facing the magnetic steel, and the internal air path is connected to the second axial air path through the second end air path.

[0014] Preferably, there are at least two second axial air passages, and the at least two second axial air passages are evenly distributed along the circumference of the rear short axis.

[0015] Preferably, a second stop flange is provided at one end of the rear short shaft away from the magnetic steel, and the second stop flange stops at the axial outer side of the sleeve.

[0016] Preferably, an annular second guide groove is provided on the end surface of the rear short shaft away from the magnetic steel, and the second guide groove is connected to each second axial air path.

[0017] Preferably, the total cross-sectional area of ​​the first axial air passage is S1, the cross-sectional area of ​​the internal air passage is S2, and S2: S1 = 1-5.

[0018] According to another aspect of the present application, a motor is provided, including a motor rotor, which is the motor rotor described above.

[0019] Preferably, the motor further includes a motor stator, a casing, a front end cover and a rear end cover, the motor stator is fixedly disposed in the casing, the motor rotor is sleeved in the motor stator, the front end cover and the rear end cover are fixedly disposed at both ends of the casing, an external air path is formed between the motor stator and the motor rotor, and the through air path inside the motor rotor forms an internal air path.

[0020] Preferably, the rear end cover and / or the end of the casing close to the rear end cover are provided with an air inlet, and the front end cover and / or the end of the casing close to the front end cover are provided with an air outlet. After the air enters the casing from the air inlet, part of it flows through the external air path, part of it flows through the internal air path, and then flows out from the air outlet.

[0021] The motor rotor provided by the present application includes a front short shaft, a rear short shaft, a magnetic steel and a sheath, wherein the front short shaft, the magnetic steel and the rear short shaft are all sleeved in the sheath, the magnetic steel is located between the front short shaft and the rear short shaft, an internal air path penetrating along the axial direction is arranged on the magnetic steel, a first axial air path is arranged on the front short shaft, and a second axial air path is arranged on the rear short shaft, the first axial air path, the internal air path and the second axial air path are connected in sequence to form a through air path penetrating the motor rotor along the axial direction. The motor rotor can be connected with the first axial air path and the second axial air path at both ends by setting an internal air path penetrating axially inside the magnetic steel, so as to form an internal cooling path for cooling the inside of the magnetic steel, and at the same time, an external cooling path can be formed outside the motor rotor, and two cooling paths can be formed on the surface and inside of the rotor, so as to realize simultaneous cooling of the magnetic steel, the surface and the inside of the sheath in the rotor heating section, so as to make the rotor cooling more sufficient and achieve a better cooling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic cross-sectional structural diagram of a motor according to an embodiment of the present application;

[0023] Figure 2 This is a schematic cross-sectional structural diagram of a motor rotor according to an embodiment of the present application;

[0024] Figure 3 This is a schematic diagram of the exploded structure of a motor rotor according to an embodiment of the present application;

[0025] Figure 4 This is a schematic structural diagram of the front short shaft of the motor rotor according to one embodiment of the present application;

[0026] Figure 5 A schematic diagram of the three-dimensional structure of the front short shaft of the motor rotor according to one embodiment of the present application;

[0027] Figure 6 It is a schematic diagram of the three-dimensional structure of the magnetic steel of the motor rotor according to an embodiment of the present application.

[0028] The reference numerals are as follows:

[0029] 1. Front cover; 10. Air outlet; 11. Rear cover; 12. Air inlet; 2. Casing; 3. Motor stator; 4. Front short shaft; 40. Motor rotor; 41. First axial air path; 42. First end air path; 43. First guide groove; 5. Magnetic steel; 51. Internal air path; 6. Rear short shaft; 61. Second axial air path; 62. Second end air path; 63. Second guide groove; 7. Sheath; 8. External air path; 9. Internal air path. DETAILED DESCRIPTION

[0030] See also Figures 1 to 6 As shown, according to an embodiment of the present application, the motor rotor includes a front short shaft 4, a rear short shaft 6, a magnetic steel 5 and a sheath 7, the front short shaft 4, the magnetic steel 5 and the rear short shaft 6 are all sleeved in the sheath 7, the magnetic steel 5 is located between the front short shaft 4 and the rear short shaft 6, an internal air path 51 is provided on the magnetic steel 5 that runs through in the axial direction, the central axis of the magnetic steel 5 is located in the internal air path 51, the front short shaft 4 is provided with a first axial air path 41, the rear short shaft 6 is provided with a second axial air path 61, the first axial air path 41, the internal air path 51 and the second axial air path 61 are connected in sequence to form a through air path that runs through the motor rotor in the axial direction. The internal air path 51 here refers to the air path that is provided inside the magnetic steel 5, rather than on the outer wall of the magnetic steel 5, so that the internal air path 51 can mainly cool the inside of the magnetic steel 5.

[0031] The motor rotor is provided with an internal air path 51 axially penetrating inside the magnetic steel 5, which can be connected with the first axial air path 41 and the second axial air path 61 at both ends to form an internal cooling path for cooling the inside of the magnetic steel 5. At the same time, an external cooling path can be formed outside the motor rotor. Two cooling paths can be formed on the surface and inside of the rotor to achieve simultaneous cooling of the magnetic steel of the rotor heating section and the surface and inside of the sheath 7, so that the rotor is cooled more fully and a better cooling effect is achieved.

[0032] In one embodiment, the internal air path 51 is located at the center of the magnetic steel 5. Setting the internal air path 51 at the center of the magnetic steel 5 can ensure that when the cooling airflow flows through the internal air path 51 of the magnetic steel 5, a more uniform cooling effect is formed on the magnetic steel 5.

[0033] In one embodiment, the internal air passage 51 is a circular hole, and the central axis of the internal air passage 51 coincides with the central axis of the magnetic steel 5. In this embodiment, the magnetic steel 5 is a cylinder with a circular axial through hole in the middle, and the circular hole and the magnetic steel 5 share the same central axis, so that the radial wall thickness of each position of the magnetic steel 5 is the same, which can more effectively ensure that the cooling airflow cools the magnetic steel 5 uniformly.

[0034] In one embodiment, the first axial air passage 41 is located on the outer peripheral wall of the front short shaft 4 and / or the inner peripheral wall of the sheath 7, and the end surface of the front short shaft 4 facing the magnetic steel 5 is provided with a first end air passage 42, and the internal air passage 51 is connected with the first axial air passage 41 through the first end air passage 42. The first axial air passage 41 is arranged on the outer peripheral wall of the front short shaft 4 and / or the inner peripheral wall of the sheath 7, which can facilitate the processing of the first axial air passage 41, and will not affect the shaft end structure, and can facilitate the internal cooling of the sheath 7. The first end air passage 42 can facilitate the communication between the first axial air passage 41 and the internal air passage 51, and will not affect the axial matching relationship between the front short shaft 4 and the magnetic steel 5. When the front short shaft 4 and the magnetic steel 5 are axially connected, the internal air passage can still be effectively guaranteed to be unobstructed, and the internal part of the magnetic steel 5 can be effectively cooled.

[0035] In this embodiment, the first axial air path 41 penetrates circumferentially along the outer periphery of the front short shaft 4, and the first end air path 42 extends from the end face center of the front short shaft 4 to the outer peripheral wall of the front short shaft 4, and is connected with the first axial air path 41, and the first end air path 42 matches the position of the first end air path 42 in the circumferential direction, so that the two can be smoothly connected to the air path structure inside the rotor.

[0036] In one embodiment, there are at least two first axial air passages 41, and at least two first axial air passages 41 are evenly distributed along the circumference of the front short shaft 4, which can ensure that the first axial air passage 41 can evenly cool the circumference of the front short shaft 4 and the circumference of the jacket 7, further improving the cooling uniformity and the cooling effect. In other embodiments, the number of the first axial air passage 41 can also be one.

[0037] In one embodiment, a first stop flange is provided at one end of the front short shaft 4 away from the magnetic steel 5, and the first stop flange stops at the axial outer side of the sleeve 7. In this embodiment, by providing the first stop flange at one end of the front short shaft 4 away from the magnetic steel 5, the axial installation position of the front short shaft 4 on the sleeve 7 can be positioned, thereby ensuring the accuracy of the axial installation position of the front short shaft 4 on the sleeve 7.

[0038] In one embodiment, the outer peripheral wall of the first stop flange is flush with the outer peripheral wall of the sheath 7, which can obtain a better appearance effect and improve the consistency of the overall structure.

[0039] In one embodiment, an annular first guide groove 43 is provided on the end surface of the front short shaft 4 away from the magnetic steel 5, and the first guide groove 43 is connected to each first axial air path 41. When the number of the first axial air paths 41 is two, the first guide groove 43 can be used to connect each first axial air path 41 from the end of the front short shaft 4, so that the airflow can effectively cool the end of the front short shaft 4 at the location of the first guide groove 43, further improving the cooling effect of the front short shaft 4. In one embodiment, the width of the first guide groove 43 increases gradually along the direction away from the magnetic steel 5, forming an inverted triangle air outlet shape, which is convenient for the diffusion or convergence of the airflow.

[0040] In one embodiment, the second axial air passage 61 is located on the outer peripheral wall of the rear short shaft 6 and / or the inner peripheral wall of the sheath 7, and the end surface of the rear short shaft 6 facing the magnetic steel 5 is provided with a second end air passage 62, and the internal air passage 51 is connected with the second axial air passage 61 through the second end air passage 62. The second axial air passage 61 is arranged on the outer peripheral wall of the rear short shaft 6 and / or the inner peripheral wall of the sheath 7, which can facilitate the processing of the second axial air passage 61, and will not affect the shaft end structure, and can facilitate the internal cooling of the sheath 7. The second end air passage 62 can facilitate the communication between the second axial air passage 61 and the internal air passage 51, and will not affect the axial matching relationship between the rear short shaft 6 and the magnetic steel 5. When the rear short shaft 6 and the magnetic steel 5 are axially connected, the internal air passage can still be effectively guaranteed to be unobstructed, and the internal part of the magnetic steel 5 can be effectively cooled.

[0041] In this embodiment, the second axial air path 61 penetrates the outer periphery of the rear short shaft 6 in the circumferential direction, and the second end air path 62 extends from the end face center of the rear short shaft 6 to the outer peripheral wall of the rear short shaft 6, and is connected with the second axial air path 61, and the second end air path 62 matches the position of the second end air path 62 in the circumferential direction, so that the two can be smoothly connected to the air path structure inside the rotor.

[0042] In one embodiment, there are at least two second axial air passages 61, and at least two second axial air passages 61 are evenly distributed along the circumference of the rear short shaft 6, which can ensure that the first axial air passage 41 can evenly cool the circumference of the front short shaft 4 and the circumference of the jacket 7, further improving the cooling uniformity and the cooling effect. In other embodiments, the number of the first axial air passage 41 can also be one.

[0043] In one embodiment, a second stop flange is provided at one end of the rear short shaft 6 away from the magnetic steel 5, and the second stop flange stops at the axial outer side of the sleeve 7. In this embodiment, by providing the second stop flange at one end of the rear short shaft 6 away from the magnetic steel 5, the axial installation position of the rear short shaft 6 on the sleeve 7 can be positioned, thereby ensuring the accuracy of the axial installation position of the rear short shaft 6 on the sleeve 7.

[0044] In one embodiment, the outer peripheral wall of the second stop flange is flush with the outer peripheral wall of the sheath 7, which can obtain a better appearance effect and improve the consistency of the overall structure.

[0045] In one embodiment, an annular second guide groove 63 is provided on the end surface of the rear short shaft 6 away from the magnetic steel 5, and the second guide groove 63 is connected to each second axial air path 61. When the number of the second axial air paths 61 is two, the second guide groove 63 can be used to connect each second axial air path 61 from the end of the rear short shaft 6, so that the airflow can effectively cool the end of the rear short shaft 6 at the location of the second guide groove 63, further improving the cooling effect of the rear short shaft 6.

[0046] In one embodiment, the width of the second guide groove 63 increases gradually along the direction away from the magnetic steel 5, forming an inverted triangle air outlet shape, which facilitates the diffusion or convergence of the airflow.

[0047] In one embodiment, the total cross-sectional area of ​​the first axial wind passage 41 is S1, the cross-sectional area of ​​the internal wind passage 51 is S2, and S2: S1 = 1 to 5. The total cross-sectional area of ​​the second axial wind passage 61 is equal to the total cross-sectional area of ​​the first axial wind passage 41, or is greater than the cross-sectional area of ​​the first axial wind passage 41. In this case, the cooling gas can flow more smoothly along the second axial wind passage 61 to the internal wind passage 51 to the first axial wind passage 41, and it is also more convenient for the cooling gas to enter the rotor.

[0048] According to an embodiment of the present application, the motor includes a motor rotor 40 , which is the motor rotor mentioned above.

[0049] In one embodiment, the motor also includes a motor stator 3, a casing 2, a front cover 1 and a rear cover 11. The motor stator 3 is fixedly arranged in the casing 2, the motor rotor 40 is sleeved in the motor stator 3, the front cover 1 and the rear cover 11 are fixedly arranged at both ends of the casing 2, an external air path 8 is formed between the motor stator 3 and the motor rotor 40, and the through air path inside the motor rotor 40 forms an internal air path 9.

[0050] In this embodiment, the air gap between the stator and the rotor forms an outer wind path 8, and the first axial wind path 41, the first end wind path 42, the inner wind path 51, the second end wind path 62 and the second axial wind path 61 inside the rotor together form an inner wind path 9 of the rotor.

[0051] When the motor is working, external cooling gas enters the motor through the air inlet 12 of the rear end cover 11. Inside the motor, the cooling gas is divided into two paths, entering the external air path 8 and the internal air path 9 respectively. In the external air path 8 and the internal air path 9, the cooling gas fully exchanges heat with the motor rotor and then flows out from the outlets of the external air path 8 and the internal air path 9. Then, it flows out of the motor through the air outlet 10 of the front end cover 1, thereby taking away the heat generated by the motor rotor 40.

[0052] In one embodiment, the rear end cover 11 and / or the end of the casing 2 close to the rear end cover 11 are provided with an air inlet 12, and the front end cover 1 and / or the end of the casing 2 close to the front end cover 1 are provided with an air outlet 10. After the air enters the casing 2 from the air inlet 12, part of it flows through the external air path 8, part of it flows through the internal air path 9, and then flows out from the air outlet 10.

[0053] In this embodiment, the inlet and outlet of the cooling gas can be both set on the front cover 1 and the rear cover 11, or both set on the casing 2, or simultaneously opened on the front cover 1, the rear cover 11 and the casing 2, so as to further increase the inlet and outlet air volume and improve the heat exchange efficiency.

[0054] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0055] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A motor rotor, characterized in that: The motor comprises a front short shaft (4), a rear short shaft (6), a magnetic steel (5) and a sheath (7); the front short shaft (4), the magnetic steel (5) and the rear short shaft (6) are all sleeved in the sheath (7); the magnetic steel (5) is located between the front short shaft (4) and the rear short shaft (6); an internal air passage (51) penetrating along the axial direction is provided on the magnetic steel (5); a first axial air passage (41) is provided on the front short shaft (4); a second axial air passage (61) is provided on the rear short shaft (6); the first axial air passage (41), the internal air passage (51) and the second axial air passage (61) are connected in sequence to form a through air passage penetrating along the axial direction through the motor rotor; The internal air passage (51) is located at the center of the magnetic steel (5); the first axial air passage (41) is located on the outer peripheral wall of the front short shaft (4) and / or the inner peripheral wall of the sheath (7); a first end air passage (42) is provided on the end surface of the front short shaft (4) facing the magnetic steel (5); and the internal air passage (51) is connected to the first axial air passage (41) through the first end air passage (42); There are at least two first axial air passages (41), and the at least two first axial air passages (41) are evenly distributed along the circumference of the front short axis (4). The total cross-sectional area of ​​the first axial air passages (41) is S1, and the cross-sectional area of ​​the internal air passage (51) is S2, where S2:S1=1-5.

2. The motor rotor according to claim 1, characterized in that: The internal air path (51) is a circular hole, and the central axis of the internal air path (51) coincides with the central axis of the magnetic steel (5).

3. The motor rotor according to claim 1, characterized in that: A first stop flange is provided at one end of the front short shaft (4) away from the magnetic steel (5), and the first stop flange stops at the axial outer side of the sleeve (7).

4. The motor rotor according to claim 1, characterized in that: An annular first guide groove (43) is provided on the end surface of the front short shaft (4) away from the magnetic steel (5), and the first guide groove (43) is connected to each of the first axial air passages (41).

5. The motor rotor according to claim 1, characterized in that: The second axial air passage (61) is located on the outer peripheral wall of the rear short shaft (6) and / or the inner peripheral wall of the sleeve (7); a second end air passage (62) is provided on the end surface of the rear short shaft (6) facing the magnetic steel (5); and the internal air passage (51) is connected to the second axial air passage (61) via the second end air passage (62).

6. The motor rotor according to claim 5, characterized in that: There are at least two second axial air passages (61), and the at least two second axial air passages (61) are evenly distributed along the circumference of the rear short axis (6).

7. The motor rotor according to claim 5, characterized in that: A second stop flange is provided at one end of the rear short shaft (6) away from the magnetic steel (5), and the second stop flange stops at the axial outer side of the sleeve (7).

8. The motor rotor according to claim 7, characterized in that: An annular second guide groove (63) is provided on the end surface of the rear short shaft (6) away from the magnetic steel (5), and the second guide groove (63) is connected to each of the second axial air passages (61).

9. A motor, comprising a motor rotor (40), characterized in that: The motor rotor is the motor rotor according to any one of claims 1 to 8.

10. The motor according to claim 9, characterized in that The motor further comprises a motor stator (3), a casing (2), a front end cover (1) and a rear end cover (11); the motor stator (3) is fixedly arranged in the casing (2); the motor rotor (40) is sleeved in the motor stator (3); the front end cover (1) and the rear end cover (11) are fixedly arranged at two ends of the casing (2); an external air passage (8) is formed between the motor stator (3) and the motor rotor (40); and an internal air passage (9) is formed through the air passage inside the motor rotor (40).

11. The motor according to claim 10, characterized in that The rear end cover (11) and / or the housing (2) are provided with an air inlet (12) at one end close to the rear end cover (11), and the front end cover (1) and / or the housing (2) are provided with an air outlet (10) at one end close to the front end cover (1). After the air enters the housing (2) from the air inlet (12), part of the air flows through the external air passage (8), part of the air flows through the internal air passage (9), and then flows out from the air outlet (10).

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